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![Topic
1 80-year old patient with severe aortic valve stenosis prior to trans-catheter
aortic valve implantation (TAVI). Pre-procedural Flash Spiral
angiography was performed using high-pitch spiral data acquisition pro-spectively
triggered at 60% of the R-R interval (128 x 0.6 mm slices,
100 kV, 320 mAs, SOMATOM Definition Flash). For thoraco-abdominal
angiography including the coronary arteries (Arrowhead) only 40 ml of
contrast agent was used (flow rate 4 ml /s). Estimated effective radiation
dose was 4.3 mSv. at a scan time of 1.7 seconds.
Images show assessment of aortic annulus diameters in syngo.via (Fig.
1A dotted line) as well as distances between the aortic annulus and the
coronary ostia. In addition, peripheral arteries have been evaluated for
significant stenosis (Fig. 1B). The red arrow indicates an occluded iliac
artery, making transfemoral access impossible here. The same data also
shows pronounced calcification along the whole thoracic aorta (Fig. 1C).
1 Cardiovascular News, Transcatheter heart valve
replacement: A European perspective,
www.cxvascular.com, Jan 2010
2 Valve Implantation for Aortic Stenosis in Patients
Who Cannot Undergo Surgery, N Engl J Med
2010
3 Aregger F, Wenaweser P, Hellige GJ, et al. Risk of
acute kidney injury in patients with severe aortic
valve stenosis undergoing transcatheter valve
replacement. Nephrol Dial Transplant 2009; 24:
2175–2179.
4 Vahanian A, Alfieri OR, Al-Attar N, et al. Transcath-eter
valve implantation for patients with aortic
stenosis: a position statement from the European
Association of Cardio-Thoracic Surgery (EACTS)
and the European Society of Cardiology (ESC), in
collaboration with the European Association of
Percutaneous Cardiovascular Interventions
(EAPCI). EuroIntervention 2008; 4: 193-199.
2 Up to 60%
less contrast
media by use of
high-pitch spiral
DSCT angio-graphy
of the
complete aorta
– compared to
other CT tech-nologies.
Courtesy of
University
of Erlangen-
Nuremberg,
Erlangen,
Germany
140 ml*
100 ml#
SOMATOM Sessions · November 2010 · www.siemens.com/healthcare-magazine 17
gies need about 6–9 seconds). This per-mits
a tremendous reduction of contrast
agent by 50–60%, which is crucial for
patients with renal insufficiency under-going
a subsequent TAVI procedure.
Compared to approximately 100–140 ml
of contrast agent needed in the past for
a CT angiography of the entire aorta, it
is now possible to use only 40 ml (flow
rate 4 ml/s) for the same examination,
which poses a significantly reduced risk
of Contrast Induced Nephropathy (CIN)
in this patient population (Fig. 2).
Accurate and fast planning
with syngo.via
The decision whether a patient is suit-able
for a catheter-based procedure and
the pre-operative planning with the
selection of the access route are based
upon results of the CT angiography. The
size of the aortic annulus for selection of
the valve prosthesis and the angulation
of the invasive fluoroscopy which allows
for simulating the optimal projection of
the aortic valve during the TAVI proce-dure
can be predicted from the same
DSCT angiography data with the support
of syngo.via.* This leads to further con-trast
media savings during the invasive
procedure since the syngo.via* software
automatically provides the correspond-ing
C-arm position.
On the basis of this protocol and ana-tomical
measurements by Flash Spiral
CT, physicians are able to quickly per-form
more patient friendly and precise
catheter-based procedures.
The time consuming planning of the
procedure is very well supported by the
many automated pre-processing steps
in the new syngo.via* software which
in early tests could show to reduce plan-ning
time by more than 33% (10 min.
versus 15 min.).
In a nutshell: Flash Spiral
and syngo.via
In conclusion the Definition Flash,
combined with the highly automated
syngo.via* workflow modules, provide
the most possible patient friendly and
accurate pre-operation planning solution
available. The high potential for cost
reduction coming from fewer patients
suffering acute CIN and therefore
requesting less of the expensive aftercare
is not yet taken into account herein.
SOMATOM Definition Flash:
www.siemens.com/SOMATOM-Definition-
Flash
CT Cardiovascular Engine:
www.siemens.com/CT-cardiology
Single-Source CT
for Abdominal
Aorta
160
140
120
100
80
60
40
20
0
*Loewe C, Eur Radiol 2010; #Wu W, AJR 2009; §Flash Thorax Protocol
40 ml§
Amount of Contrast Agent [mL]
Single-Source CT
for Triple Rule Out
Dual Source CT
SOMATOM
Definition Flash
2
News
* syngo.via can be used as a standalone device or
together with a variety of syngo.via based soft-ware
options, which are medical devices in their
own rights.
1C](https://image.slidesharecdn.com/somatomsession27-00079186-00270172-140821163309-phpapp01/85/Somatom-session-27-17-320.jpg)
![Business
Right after its introduction, the manufacturing lines of the SOMATOM Definition AS
were filled and have remained filled since then.
SOMATOM Sessions · November 2010 · www.siemens.com/healthcare-magazine 31
With the introduction of the SOMATOM
Definition AS – the world’s first Adaptive
Scanner – in 2007, Siemens opened
a new chapter in single-source CT tech-nology.
The revolutionary idea was to
combine high-end CT imaging for any
clinical task at lowest possible dose with
a scanner design that didn’t exclude
patients because of the system’s geome-try.
And all this with a footprint small
enough to fit it into literally minimum
space. The result: for the first time, a
system actively adapts itself to virtually
every clinical situation. Offering a 128-
slice CT system with a pitch-independent
isotropic resolution of 0.33 mm, a rota-tion
time of 0.3 seconds and 100 kW
generator power, it delivers enough
reserves to meet virtually all clinical
tasks. With a 78 cm bore diameter, a scan
range of 200 cm that can be acquired in
approximate 10 seconds at highest reso-lution
and a table load capacity of up to
300 kg, whole body examinations in
acute care or bariatric imaging were
turned into clinical routine. Groundbreak-ing
innovations introduced new dimen-sions
in CT: the Adaptive 4D Spiral over-came
the limitations of a static detector
design and allowed covering whole
organs in 4D – and the still unique 3D
interventional suite provided 3D guided
intervention support. This was all realized
within a system that could be fit nearly
everywhere with only an 18 m² footprint,
freely selectable air or water cooling and
full on-site upgradeability.
After the first installations, users were
immediately excited. Among the first was
Prof. Joe Schoepf from the Medical Uni-versity
of South Carolina. In an interview,
he commented that the “Definition AS
will effectively overcome a number of
limitations we face today. […] All the
guess work is taken out” and it “has all
the power […] to capture clear images
unmarred by excess noise, even in obese
patients.” Following this excitement,
many publications proved that the
SOMATOM Definition AS kept the prom-ises
given. In 2009, a new software ver-sion
was rolled out to all customers,
underlining Siemens’ dedication to cus-tomer
care. With innovative features like
Neuro BestContrast, it boosted the
already outstanding image quality even
further and made IRIS – the Iterative
Reconstruction in Image Space – avail-able
for the SOMATOM Definition AS.
Naturally, this convinced the market and
the result was the fastest ramp-up in
Siemens CT’s history. After the first
installation in May 2008, the SOMATOM
Definition AS surpassed 500 installations,
in September 2009, and then achieved
the 1,000th installation in September
2010 in Washington DC, USA.
Now, Siemens has taken the SOMATOM
Definition AS to the next level with the
introduction of FAST CARE at this year’s
RSNA. For decades, Siemens has spear-headed
dose reduction and has intro-duced
many innovations following the
“As Low as Reasonably Achievable”
(ALARA) principle. For this, Siemens’ initi-ated
its CARE (Combined Applications to
Reduce Exposure) philosophy more than
15 years ago. Additionally, the SOMATOM
Definition AS brought many innovations
like the Adaptive Dose Shield that, for the
first time, virtually eliminated unneces-sary
over-radiation in every spiral scan.
The new FAST (Fully Assisting Scanner
Technologies) philosophy now aims to
give customers the possibility to maxi-mize
clinical outcome – meaning to
achieve best clinical results, but with
significantly less resources bound to the
CT system. The ultimate goal: provide
medical professionals more time for
patients – or patient-centric productivity.
The new FAST features, like FAST Plan-ning
or FAST Spine, simplify typically time
consuming and complex procedures. The
scanning process gets more structured
and results become more reproducible.
Integrating the capabilities of syngo.via,*
Siemens’ revolutionary, new imaging
software, the complete examination –
from scan preparation to data evaluation
– is streamlined. This gives medical pro-fessionals
significantly more time for
what is of utmost importance: the diag-nosis
and interaction with their patients,
leading ultimately to improved clinical
results with less patient burden. This
combination of highest image quality at
lowest dose and highest patient-centric
productivity is the lever to maximizing
clinical outcomes. The new SOMATOM
Definition AS with FAST CARE will be
available from March 2011.
* syngo.via can be used as a standalone device or
together with a variety of syngo.via based soft-ware
options, which are medical devices in their
own rights.](https://image.slidesharecdn.com/somatomsession27-00079186-00270172-140821163309-phpapp01/85/Somatom-session-27-31-320.jpg)
![Clinical Results Cardio-Vascular
Case 3
CT Dynamic Myocardial Stress Perfusion
Imaging – Correlation with SPECT
Kheng-Thye Ho, FACC,* Kia-Chong Chua, MSC,*
Ernst Klotz,** and Christoph Panknin,**
*Department of Cardiology, Tan Tock Seng Hospital, Singapore, Republic of Singapore
**Business Unit CT, Siemens Healthcare, Forchheim, Germany
HISTORY
A 61-year-old male with cardiac risk fac-tors
of hypertension and hyerlipidemia
presented with symptoms of atypical
chest pain. Resting ECG was unremark-able.
Dipyridamole-stress nuclear myocar-dial
perfusion imaging (NMPI) had dem-onstrated
a very large, reversible defect
involving the apex, anterior wall and sep-tum.
The total defect size was quantified
1
42 SOMATOM Sessions · November 2010 · www.siemens.com/healthcare-magazine
1 CT dynamic stress MPI with SPECT
correlation in the mid-ventricular short
axis (1A) and the horizontal long axis
view (1B). Stress are images in the
upper quadrants, rest images below;
CT perfusion to the left of the corre-sponding
SPECT.
2 Invasive angiography findings:
Total occlusion of the proximal LAD
and a 90% lesion in OM3 (2A, arrow),
and 75% lesion in the RPDA branch
of the otherwise normal RCA (2B,
arrowhead).
as 34% of the left ventricle. Left ventricu-lar
ejection fraction was estimated as
65% in the post-stress images by gating.
Post-stress dilatation was noted in the
scan, which is an adverse prognostic sign
in the presence of coronary artery dis-ease.
Invasive coronary angiography
demonstrated total occlusion of the prox-imal
LAD, with collaterals arising from
both the LCx and RCA. There was also a
90% lesion in the third obtuse marginal
branch (OM3) and a 75% lesion in the
right posterior descending artery (RPDA)
branch of the right coronary artery
(RCA). CT myocardial perfusion imaging
(MPI) was performed prior to CABG.[1]
The patient underwent successful coro-nary
bypass surgery, with a left internal
1A 1B
2A 2B](https://image.slidesharecdn.com/somatomsession27-00079186-00270172-140821163309-phpapp01/85/Somatom-session-27-42-320.jpg)
![Case 4
SOMATOM Defi nition Flash
Motion-free Thoracic Infant Scan: Follow-Up
Study After Chemotherapy
By Susann Skoog, MD, Nils Dahlström MD, and Petter Quick
Department of Radiology and Center for Medical Image Science and Visualization (CMIV),
Linköping University Hospital, Linköping, Sweden
HISTORY
A three-year-old boy with small
(7-8 mm diameter) lung metastases
from a germ-cell tumor, successfully
treated with chemotherapy, was
referred for follow-up CT of the thorax.
In a previously acquired CT-examination
without sedation, utilizing DLP 51.95
mGycm, 3.28 mGy CTDi vol / scan
length 140 mm, the patient had been
coope rative.
In the present Flash scan, no remaining
metastases were identified and the
serum tumor marker Alpha Fetoprotein
(AFP) levels were normal.
EXAMINATION PROTOCOL
DIAGNOSIS
The ultra-fast thoracic scan mode, using
pitch value of 3, did not reveal any met-astatic
lesions or other pathological find-ings
in the thorax. Both lungs were well
perfused and there was no sign of any
enlarged lymph nodes. The size of the
thymus was increased moderately.
Inverted maximum intensity projection
(MIP) showed a regular bronchial tree.
COMMENTS
Continuous follow-up CT examinations
are necessary to monitor the treatment
effect and determine the complete
Scanner SOMATOM Definition Flash
Scan mode Flash Spiral Thorax Eff. Dose 0.54 mSv
Scan area Thorax CTA Pitch 3
Scan length 172 mm Slice collimation 128 x 0.6 mm
Scan direction Cranio-caudal Slice width 0.75 mm
Scan time 0.42 s Reconstruction increment 0.6 mm
Tube voltage 120 kV Reconstruction kernel B31f
Tube current 20 mAs Contrast
Dose modulation CARE Dose4D Volume 30 ml Ultravist® 370 mg / ml
CTDIvol 1.23 mGy Flow rate 1 ml/s
Rotation time 0.28 s Start delay 30 s
DLP 30 mGy cm Postprocessing syngo InSpace4D
44 SOMATOM Sessions · November 2010 · www.siemens.com/healthcare-magazine
patient response. Using the high-pitch
spiral acquisition of the SOMATOM
Definition Flash CT, patients can always
be examined with greatly reduced radia-tion
dose in comparison to standard CT
protocols. In this case only 0.54 mSv*
were necessary to be applied.
The fast scan mode which acquired the
patients’ thorax in only 0.42 seconds
avoided the need to sedate this pediatric
patient. The resulting images were
obtained motion free and delivered excel-lent
and valuable data for a safe diagno-sis
without the need of a second scan.
Clinical Results Oncology
* Effective Dose was calculated using the published conversion factor for a pediatric (5 year old) chest of 0.036 mSv (mGy cm)-1 [1].
To take into account that Siemens calculates the CTDi in a 32 cm CTDi phantom, an additional correction factor of 2 had to be applied.
[1] McCollough CH et al Strategies for Reducing Radiation Dose in CT.](https://image.slidesharecdn.com/somatomsession27-00079186-00270172-140821163309-phpapp01/85/Somatom-session-27-44-320.jpg)
![Case 7
SOMATOM Spirit: Follow-Up Examination
of Cerebral Meningioma
By Wolfgang Gerlach, MD,* Andreas Blaha**
*Private Practice, Heidenheim, Germany,
**Business Unit CT, Siemens Healthcare, Forchheim, Germany
HISTORY
This 74-year-old female patient under-went
a regular follow up procedure
of the known meningioma located
in the ventral part of the clivus. To
exclude progress of the meningioma
a CT-Angiography was ordered.
DIAGNOSIS
The cerebral CT-Angiography (CTA) was
performed with 80 ml of contrast media
to achieve a good delineation of the
meningioma. A homogeneous opacifica-tion
of the lesion needed to be achieved
(Mean density could be measured with
110 Hounsfield units, HU). The menin-gioma
is situated at the clivus, almost
extending to the foramen magnum. The
size was measured with 2.9 x 2.5 cm.
The sagittal view of the CTA shows the
extension towards the spinal cord, but no
derogation of the spinal cord could be
seen. No abnormity of the cerebral vas-cular
system could be detected.
COMMENTS
The patient requires continuous moni-toring
to detect early signs of progression
of the lesion. Therefore a low dose pro-tocol
was selected 0.5 mSv*. No pro-gression
could be observed, so the next
monitoring examination is recommended
in 12 months.
To achieve the pure arterial contrast
1 Cranio-caudal view of the CTA, good opacification of the meningioma (arrow).
1
50 SOMATOM Sessions · November 2010 · www.siemens.com/healthcare-magazine
region of the patients meningioma and
makes it the preferred visualization
method for detecting and monitoring
cerebral meningioma.
timing an automatic contrast bolus
tracking software (CARE Bolus CT) was
utilized. CT provides the exact measure-ment
and location in the very dense
Clinical Results Oncology
* Effective Dose was calculated using the pub-lished
conversion factor for an adult head of
0.0021mSv (mGy cm)-1 [1].
[1] McCollough CH et al. Strategies for Reduc-ing
Radation Does in CT, Radiol. Clin. N. Am. 47:
(2009) 27-40.](https://image.slidesharecdn.com/somatomsession27-00079186-00270172-140821163309-phpapp01/85/Somatom-session-27-50-320.jpg)
![Science
Dose Parameters and Advanced Dose
Management on SOMATOM Scanners
The measurement and calculation of radiation dose in CT is an important
topic for an effi cient dose management. Quantities such as the CTDI, DLP
and effective dose are useful when used appropriately. Now Siemens takes
dose management to a new level by providing tools such as Dose Structured
Reports and CARE Analytics.
By Stefan Ulzheimer, PhD, Christianne Leidecker, PhD, and Heidrun Endt
Business Unit CT, Siemens Healthcare, Forchheim, Germany
The assessment and management of
patient dose has become one of the most
frequently discussed topics in Computed
Tomography. On SOMATOM Scanners,
the reporting of established dose para-meters
like Computed Tomography Dose
Index (CTDI) and Dose Length Product
(DLP) has been implemented since 1999.
For each exam, the information is avail-able
in the patient protocol, and can be
viewed and archived as a DICOM image.
With Dose Structured Reports (Dose SR)
Siemens is taking the next step to enable
more transparency in terms of radiation
dose. Furthermore, tools like CARE
Analytics provide an easy means to eval-uate
Dose SR.
Technical dose parameters –
CTDIvol and DLP
The CTDI is the primary dose measure-ment
concept in CT and is defined by
the International Electrotechnical Com-mission
(IEC) [1] and adopted by various
national bodies such as for example by
the US Food and Drug Administration
(FDA). The weighted volume CT Dose
Index, CTDIvol represents the average
Calculating effective dose from scanner dose information.
68 SOMATOM Sessions · November 2010 · www.siemens.com/healthcare-magazine
absorbed dose within the scan volume
for standardized phantoms. Their diame-ters
are 16 and 32 cm, to approximate
conditions for head and body examina-tions
so the phantoms do not adequately
represent patient cross-sections. How-ever
the CTDIvol is an objective technical
dose parameter based on a directly mea-sured
quantity. It takes into account pro-tocol-
specific parameters and is useful to
compare different scan protocols across
various CT scanners. Thus, IEC standards
require the prospective display of the
CTDIvol on the console of the CT scanner.
1 Calculating effective
dose for adults. From the
Patient Protocol of this
abdominal scan, the DLP is
obtained:
DLP = 274 mGy·cm
Using the conversion factor
for abdominal exams,
0.015 mSv/(mGy·cm) [3],
effective dose E is estimated
to be E = 274 mGy·cm ·
0.015 mSv/(mGy·cm) =
4.1 mSv
1](https://image.slidesharecdn.com/somatomsession27-00079186-00270172-140821163309-phpapp01/85/Somatom-session-27-68-320.jpg)
![Science
Calculating effective dose from scanner dose information for a pediatric body exam.
2 Calculating effective dose for children. Using the same values as in the first example, the DLP is: DLP = 274 mGy·cm. First you have to
determine if the DLP refers to a 32 cm or 16 cm CTDI phantom. In this case, the DLP is reported in the 32 cm body CT dose phantom. This value
has to be converted to the head CT dose phantom if pediatric conversion factors published in [table 1] shall be used to compute the effective
dose: DLP = 2.0 * 274 mGy·cm = 548 mGy·cm. Note: Typical values are between 2.0 and 2.4 for Siemens scanners. Values can be found in the
System Owner Manual. Since the method of using conversion factors to determine the effective dose is a very rough method usually using a cor-rection
factor of 2.0 is sufficiently accurate for all scanners. For a 5-year old child, a factor of 0.02 mSv/(mGy·cm) for abdominal exams is used
[table 1] to estimate E. E = 548 mGy·cm · 0.02 mSv/(mGy·cm). = 11 mSv. If the DLP was already measured in the 16 cm head phantom like it is
the case on new scanners the conversion factors from table 1 can be used directly without applying an additional factor of 2.0 to 2.4.
SOMATOM Sessions · November 2010 · www.siemens.com/healthcare-magazine 69
To represent the overall dose of a given
scan protocol, the CTDIvol is multiplied
with the examination range which then
yields the DLP.
Towards assessing
patient dose
When asking the question of “what is
the radiation dose”, one really is inter-ested
in “what is the risk of this exam”?
However, information on individual
patient dose depends on multiple para-meters,
such as patient specific character-istics
and in addition to the technical
parameters of the system and exam.
The International Commission on Radia-tion
Protection (ICRP) has introduced the
concept of effective dose which repre-sents
a risk-related quantity for the con-trol
of radiation exposure and optimiza-tion
of protection. It cannot be measured
directly, but rather is calculated using
defined dosimetric models. Hence, it
applies to a reference person and does not
provide risk information for the individual.
Table 1
Region of body Conversion factor from DLP to Effective Dose in [mSv / (mGy ·cm)]
0 year old 1 year old 5 year old 10 year old Adult
Head and neck 0.013 0.0085 0.0057 0.0042 0.0031
Head 0.011 0.0067 0.0040 0.0032 0.0021
Neck 0.017 0.012 0.011 0.0079 0.0059
Chest 0.039 0.026 0.018 0.013 0.014
Abdomen and pelvis 0.049 0.030 0.020 0.015 0.015
Trunk 0.044 0.028 0.019 0.014 0.015
One practical method to calcu-late
effective dose: Conversion
factors from DLP to effective
dose for children and adults;
for different body regions as
published in [2, 3]. Please note
that the conversion factors for
children refer to a DLP measured
in a 16 cm phantom. On older
scanners or software versions
the DLP in pediatric protocols
often refers to a 32 cm phantom.
Then an additional correction
factor has to be applied.
2](https://image.slidesharecdn.com/somatomsession27-00079186-00270172-140821163309-phpapp01/85/Somatom-session-27-69-320.jpg)
![Science
3 The Dose SR can
be viewed on the
scanner console,
sent to PACS or to
an independent
server used to mon-itor
dose data.
3
Practical ways to determine
effective dose for CT exams
Several approaches to estimate effective
dose for CT exams have been investi-gated.
A generic method was proposed
to estimate effective dose from the DLP
of an exam [2], with the DLP being
reported on most systems. Conversion
factors for normalized effective dose per
DLP were obtained from Monte Carlo
calculations of effective dose for various
clinical exams. These conversion factors
depend only on the region of the body
being scanned (head, neck, thorax,
abdomen, or pelvis).
It is important to understand that calcu-lating
effective dose using this method
can always only be a rough estimate of
effective dose because many parameters
that influence effective dose are not
taken into account. The body size and
the exact location of the scanned area in
relation to the dose sensitive organs are
only two of those parameters. However,
usually this method is sufficiently exact
for the purpose the effective dose con-cept
was developed for: Radiation protec-tion
and getting an estimate on the total
exposure that is also comparable with
other sources of radiation.
As an example, Figure 1 illustrates the
calculation of the effective dose of an
abdominal scan using conversion factors
published by Shrimpton et al. [table 1].
Special considerations
for children
Conversion factors are also available for
children of various ages [table 1].
Special attention has to be paid to the fact
that the conversion factors published
apply to values reported in the head CT
70 SOMATOM Sessions · November 2010 · www.siemens.com/healthcare-magazine
dose phantom.
In the past scanners, CTDI values were
reported in the head CT dose phantom
for head exams and the body CT dose
phantom for body exams, irrespective of
the patient age. This was in line with the
original IEC standards, which did not
provide instructions for pediatric exams.
Thus, for calculations regarding pediatric
body exams, an additional calculation
step has to be performed, as illustrated
in Figure 2.
The example shown illustrates that the
same exposure leads to an effective dose
that is almost three times higher for a
five year old than an adult. While being
purely theoretical, the example shows
that, it is of utmost importance to pay
special attention when imaging pediatric
patients, in particular to use dedicated
pediatric protocols in combination with](https://image.slidesharecdn.com/somatomsession27-00079186-00270172-140821163309-phpapp01/85/Somatom-session-27-70-320.jpg)
![Science
References
1 IEC 61223-2-6 Evaluation and routine testing in
medical imaging departments – Part 2-6: Con-stancy
tests – Imaging performance of computed
tomography X-ray equipment
2 Jessen KA, Panzer W, Shrimpton PC, et al. EUR
16262: European Guidelines on Quality Criteria
for Computed Tomography. Paper presented at:
Office for Official Publications of the European
Communities; Luxembourg. 2000.
3 Shrimpton PC, Hillier MC, Lewis MA, Dunn M.
National survey of doses from CT in the UK:
2003. Br J Radiol Dec;2006 79(948):968–980.
[PubMed: 17213302]
SOMATOM Sessions · November 2010 · www.siemens.com/healthcare-magazine 71
CARE Dose4D.
To standardize dose reporting for pediat-ric
patients, future editions of IEC stan-dards
will require dose reporting in the
head CT dose phantom for pediatric
exams, irrespective of the body region
imaged. Starting with software version
syngo CT 2011A, Siemens will implement
this new requirement. As a consequence,
the conversion factors [table 1] can be
directly applied also in pediatric proto-cols.
To ease the transition, the CT dose
phantom size was added to the user
interface and it is also reported in the
Dose SR.
A new standard:
Dose Structured Reports
As the first CT manufacturer Siemens
now provides the new Dose SR almost
across its complete CT product portfolio.
The Dose SR contains comprehensive
data for each irradiation event, the accu-mulated
dose and information about the
context of the exposure. The data is pro-vided
in electronic format that can be
sent to any system which receives, stores
or processes dose information, such as
conventional PACS or workstations.
A new tool to evaluate
Dose Structured Reports:
CARE Analytics
The Dose SR can serve as the center
piece of an institution wide dose quality
control. To evaluate and analyze the
information, Siemens provides a new
free tool, CARE Analytics. It is a stand-alone
tool and can be installed on an
office computer.
With CARE Analytics, one can query Dose
SR from DICOM nodes directly. Dose
reporting data can be exported and ana-lyzed
with standard tools, such as Micro-soft
Excel™.
With the prompt implementation of
Dose SR and the new tool CARE Analytics
Siemens provides the customer with all
the information needed for a transpar-ent
dose management.](https://image.slidesharecdn.com/somatomsession27-00079186-00270172-140821163309-phpapp01/85/Somatom-session-27-71-320.jpg)
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Somatom session 27
The new FAST CARE software from Siemens aims to standardize and simplify CT scans through several innovations. It guides users intuitively through the entire scan process from planning to reconstruction. This reduces workload and potential for errors. FAST CARE also facilitates dose reduction through tools like iterative reconstruction and automatic selection of optimal scan parameters. Dr. Michael Lell expects FAST CARE to save time and improve efficiency, allowing clinics to examine more patients with fewer resources. He is also hopeful the automatic coupling of contrast injection and scanning can reduce staffing needs. Overall, FAST CARE makes CT scans safer, more reproducible and effective for both patients and clinicians.
Somatom session 27
- 1. SOMATOM Sessions Answersfor life in Computed Tomography Issue Number 27/ November 2010 RSNA-Edition /November 28th – December 03rd, 2010 Cover Story Be FAST, take CARE Page 6 News Iterative Reconstruction Reloaded Page 14 Business syngo.via: Ready for Prime Time in Clinical Practice Page 34 Clinical Results SOMATOM Defi nition Flash: Rule-Out of Coro-nary Artery Disease, Aortic Dissection and Cerebrovascular Diseases in a Single Scan Page 60 Science Dose Parameters and Advanced Dose Management on SOMATOM Scanners Page 68 27 RSNA-Edition November 2010 27 SOMATOM Sessions
- 2. Editorial 2 “WithFAST CARE we address todays’ challenges of our customers, accelerate CT workfl ows and reduce patient exposure even further.” Sami Atiya, PhD, Chief Executive Office, Business Unit Computed Tomography, Siemens Healthcare, Forchheim, Germany Cover Page: Courtesy of University of Erlangen- Nuremberg, Erlangen, Germany SOMATOM Sessions · November 2010 · www.siemens.com/healthcare-magazine
- 3. Editorial Dear Reader, Recent improvements in healthcare have created a serious backlog of patients at many medical facilities, creating a con-tradictory situation: the medical care is better but it has become more difficult to be treated as medical facilities stagger under an ever-increasing workload. Adding to the contradictory matrix is a medically well-informed public con-cerned with radiation exposure. An effi-cient, faster throughput of patients while maintaining quality care has be come the critical issue in modern health care. The creative and innovative products developed by Siemens to deal with this situation are truly amazing. The revolu-tionary, single-source SOMATOM Definition AS (and AS+) scanner that reduces many scans to a one click op-eration at extremely low dose. The second noteworthy is the unique SOMATOM Definition Flash scanner that scans an entire thorax in less than one second with sub-mSv dose and can “freeze” even the fastest beating heart, producing diagnostic quality cardiology images in minutes. We then introduced the syngo.via*, multi-modality imaging software. With syngo.via*, the reading physician can observe and analyze CT, MR, PET, Radio graphy, Fluroscopy and Angio-graphy simultaneously on a single monitor – eliminating many trips from the regular reading workplace to various workstations. Another great advantage of syngo.via* is the pre-processing André Hartung, Vice President Marketing and Sales Business Unit CT, Siemens Healthcare system. When a case is opened, many pre-processing tasks such as table re-moval, bone removal, curved planar re-for mat ting, naming of vessels, ejection frac tion calculations and orthogonal cuts are already done. The reading physician can start the interpretation and diagnosis immediately. The challenge now became combining these (and many other) systems to re-lieve pressure on hospitals and clinics by increasing throughput while maintaining quality medical care. This goal resulted in the introduction of our new FAST CARE platform at the recent RSNA convention in Chicago. When it comes to the FAST CARE plat form, incorporating “Fully Assisting Scanner Technology” (FAST) and “Com bined Applications to Reduce Ex-posure” (CARE), the name says it all. This new platform for the SOMATOM Definition family, guides the user through a CT scan in just a few intuitive steps, starting with planning, through the ac-tual scanning process, to recon struction and evaluation of clinical images. In this way, FAST prio ritizes considerations of efficiency and focuses on patient-centric productiv ity. The CARE standard combines a variety of Siemens’ innovations, like CARE kV, CARE Child or the next generation of Iterative Reconstruction, SAFIRE** that we have intro duced at this years’ RSNA. patients – including trauma or young children – from head to toe without having to repeat the scan. In addition you now have the possibility to reduce dose even further. Additionally, in keeping with our tradi-tional cooperation with out-of-house experts, – radiologists and others who are confronted daily with challenges in their daily scanning practice – we have launched the Siemens Radiation Reduc-tion Alliance (SIERRA). This panel of highly respected experts in the medical imaging field will track and provide valuable feed back and make recommen-dations on dose-related subjects to Siemens, infor mation that will mean even healthier examinations for your patients. Our ultimate goal with this prestigious group is to reduce dose exposure in CT to a level below 2.4 mSv, the annual natural level of radi ation always present in our environement. More complete information and valuable links on all these new and exciting deve-lop ments can be found in the pages of this SOMATOM Sessions issue. And invisibly em bed ded in every page is a factor that is not new here at Siemens… better health care for all patients. We wish you enjoyable and profitable reading. Sincerely, Using these powerful tools enables you to quickly examine your most challenging André Hartung ** syngo.via can be used as a standalone device or together with a variety of syngo.via based software options, which are medical devices in their own rights. ** The information about this product is being provided for planning purposes. The product is pending 510 (k) review, and is not yet commercially available in the U.S.
- 4. Content Cover Story 6 Be FAST, Take CARE News 12 CEO Corner: Excellence in Clinical Practice 12 Working with syngo.via – an In- Practice Report 14 Iterative Reconstruction Reloaded 16 Flash Spiral Dual Source CT for Precise and Patient-Friendly Transcatheter Aortic Valve Implantation (TAVI) Procedure Planning. 18 Siemens Launches SIERRA, the Siemens Radiation Reduction Alliance 19 Siemens CT Stroke Management: Helping to Save Brain and Quality of Life 20 A Pediatric Breakthrough: Auto-mated Adaptation of CT Dose Levels 22 Expanding Radiodiagnostics: University Hospital Hradec Králové, Czech Republic 24 Full Cardiac Assessment with syngo.via – Maximal Significance, Minimal Dose Contents Cover Story 6 Technology should serve the physician, not vice versa. The true task of the doctor is caring for the patient, not handling apparatus. Therefore, FAST CARE is set to raise the standard for patient-centric productivity and intro duces innovations for patient dose reduction. The result: safe, reprodu-cible examinations that involve less exposure and are therefore more effective and efficient. 4 SOMATOM Sessions · November 2010 · www.siemens.com/healthcare-magazine 20 A Pediatric Breakthrough 6 Be FAST, Take CARE 26 Advanced Imaging for Four-Legged Patients 27 SOMATOM Definition AS Open – Dedicated High-end CT for Radiation Therapy Planning 27 Among Europe’s Best 28 SOMATOM Scanners: Ahead of the Innovative Curve Business 30 1,000th SOMATOM Definition AS Installed – A Success Story 32 Time is Brain – A Comprehensive Stroke Program at the University of Utah Considerably Improves Patients’ Outcome 34 syngo.via: Ready for Prime Time in Clinical Practice 36 SOMATOM Spirit: A Choice That Paid Off All articles mentioned on the cover are designated in orange.
- 5. Content 54 VolumePerfusion CT Neuro as a Reli-able Tool for Analysis of Ischemic Stroke Within Posterior Circulation Acute Care 56 Dual Source, Dual Energy CT: Improvement of Lung Perfusion Within 5 Hours in a Patient With Acute Pulmonary Embolism 58 Differentiation of Pulmonary Emboli and Their Effect on Lung Perfusion Determined With a Low-Dose Dual Energy Scan 60 SOMATOM Definition Flash: Rule-Out of Coronary Artery Disease, Aortic Dissection and Cerebrovascular Diseases in a Single Scan 62 SOMATOM Definition Flash: RIPIT to the Rescue – Fast CT Examination for Trauma Patients Pulmonology 64 Xenon Ventilation CT Scan Demon-strates an Increase in Regional Ventilation After Bullectomy in a COPD Patient Orthopedics 66 SOMATOM Definition: Dual Energy Locates Progressive Wrist Arthritis SOMATOM Sessions · November 2010 · www.siemens.com/healthcare-magazine 5 Clinical Results Cardio-Vascular 38 SOMATOM Definition Flash Ruling out Coronary Artery Disease with 0.69 mSv 40 SOMATOM Definition Flash: Low-Dose Abdomen Pediatric Scan: Follow-Up Study of Fibromuscular Dysplasia 42 CT Dynamic Myocardial Stress Perfusion Imaging – Correlation with SPECT Oncology 44 SOMATOM Definition Flash: Motion-free Thoracic Infant Scan: Follow-Up Study After Chemotherapy 46 SOMATOM Definition Flash: Dual Energy Carotid Angiography for Rapid Visualization of Paraganglioma 48 Total Occlusion of the Left Superior Pulmonary Vein by a Metastasis Detected with Dual Energy CT 50 SOMATOM Spirit: Follow-Up Exami-nation of Cerebral Meningioma Neurology 52 SOMATOM Definition Flash: Improv-ing Image Quality of Brain Scans With IRIS, X-CARE and Neuro BestContrast Science 68 Dose Parameters and Advanced Dose Management on SOMATOM Scanners 72 IRIS and Flash: Cardio CT with Minimum Radiation Exposure Delivers Precise Images Life 74 Clinical Fellowship: Learning From the Experts in the Field 76 STAR: Specialized Training in Advances in Radiology 76 Evolve Update Facilitates Dose Savings 77 Frequently Asked Questions 77 Siemens Healthcare is Proud to Present a New Series of Live Clinical Webinars 78 News at Educate Homepage: Recommended CT Literature 78 Clinical Workshops 2011 79 Upcoming Events & Congresses 80 Corporate Magazines 81 Imprint 32 Time is Brain 60 SOMATOM Definition Flash: Rule-Out of Coronary Artery Disease
- 6. Coverstory Be FAST,Take CARE FAST CARE reduces the complexity of CT scans to just a few clicks and facilitates even more reduction of dosage. Technology should serve the physician, not vice versa. The true task of the doctor is caring for the patient, not handling apparatus. Therefore, FAST CARE is set to raise the standard for patient-centric productivity and introduces several innovations for patient dose reduction. The result: safe, reproducible examinations that involve less exposure and are therefore more effective and effi cient. Dr. Michael Lell shared his observations and expectations with us. By Hildegard Kaulen, PhD The new generation of the FAST CARE software will be availabe for all SOMATOM Definition scanners spring 2011.
- 7. The medical professionis changing. As patient numbers increase, budgets are ever-decreasing. At the same time, patients seek the assurance and the advice of the physician. In the University Clinic at Erlangen, Germany, too, the numbers of examinations have been skyrocketing, while the residence time at the clinic has been going down. Less and less resources for diagnostics are available. Associate Professor Dr. med. Michael Lell, Senior Physician at the Insti-tute of Radiology, feels the pinch, espe-cially when it comes to staff. This is why he is particularly appreciative of soft-ware solutions that not only leave him more time for his obligations as a doctor and researcher, but also optimizes the utilization of staff. When it comes to Siemens’ new FAST CARE technology, incorporating “Fully Assisting Scanner Technologies” (FAST) and “Combined Applications to Reduce Exposure” (CARE), the name says it all. The new platform for the SOMATOM Definition product family guides the user through a CT scan in just a few intuitive steps, starting with planning, through the actual scanning process, to reconstruction and evalua-tion of clinical images. In this way, FAST prioritizes considerations of efficiency and focuses on patient-centered produc-tivity. Standardization ensures that all examinations follow the same pattern, avoiding errors and uncertainty. So, scans that erroneously fail to depict parts of the target organ can be avoided in the future. At the same time, FAST CARE also offers the user new solutions for reducing the applied radiation dose and supports the consistent use of al ready available solutions. The entire CT scan thus not only becomes more intui-tive and reproducible, but also safer for the patients. Reducing users’ workloads FAST Planning, one of the new function-alities of FAST CARE, provides sugges-tions for the scan and reconstructions that are appropriate for the selected mode based on the characteristics of the organ, including the length of the exam-ination volume. Thus, for example, in the case of a cranial CT, the isocenter is automatically adapted to the position of the skull. CT scans are complex proce-dures and operating the equipment is demanding, even with standardized pro-tocols. Lell agrees: there will always be situations where the standard protocol must be adapted to the stature of the patient or the problem being investi-gated. Also, the technical staff operates not just one, but many modalities. The constant back and forth between indi-vidual applications makes high demands of staff members’ expertise and concen-tration. A program that guides users intuitively through the entire CT scan makes the task simpler, safer, more repro-ducible and more efficient. “In view of the fact that well-trained staff is increas-ingly difficult to find,” Lell continues, “this is an important aspect.” He has high expectations for the automatic cou-pling of the contrast agent injection with the scanning protocol, which will be offered as a special add-on feature for the standard package under the des-ignation CARE Contrast III. “Currently, two staff members work on examina-tions involving contrast agents,” says Lell. “One of them injects the contrast agent, while the other prepares the scan . If the injection and the scan are linked, Coverstory “A program that guides users intu-itively through the entire CT scan makes the task simpler, safer, more reproduc-ible and more effi cient.” Michael Lell, MD, PD, Departement of Radiology, University of Erlangen-Nuremberg, Erlangen, Germany we can do the same work with one less staff member. Since we have less and less staff available due to cost reasons, that would be a major economization.” If the selected scan parameters create conflicts, FAST CARE resolves them through a single click on the FAST Adjust button. On occasion, Dr. Lell explains, a selected scan protocol could combine different parameters in such a manner, that scanner will prevent the scan in order to avoid a faulty result. Currently, University of Erlangen-Nuremberg, Erlangen, Germany.
- 8. Coverstory such situationshave to be resolved man-ually, which costs time. With FAST CARE, the FAST Adjust function suggests the ideal solution. But the focus is also on faster diagnostics. This is where the strengths of syngo.via,* Siemens new, leading-edge imaging software, come into effect. The software automatically loads the images into the appropriate application and segments them in such a way that they can be adjudged with-out further ado. The physician can arrive at a final diagnosis with just a few clicks of the mouse as the images have already been pre-processed for him. The applica-tion is determined by the disease-specific criteria of the case at hand and no longer needs to be independently selected. Since syngo.via handles all preparatory steps, the physician can focus com-pletely on his actual task, namely diag-nostics. This, too, saves time and enhances diagnostic reliability. Improved image reconstruction FAST CARE also introduces SAFIRE,** Siemens’ first raw-data-based iterative reconstruction. This technique removes noise and artifacts in iterative steps in the image and raw data domain, with-out compromising image sharpness. The procedure can be used in two different ways. Either the image quality of the standard reconstruction is maintained, and the dose can be reduced, or the dose level is maintained and clinical images of noticeably higher quality are gener-ated. Until now, however, calculation of the projection data required significantly more time than the standard reconstruc-tion. For FAST CARE, the image space algorithm was enhanced and a new reconstruction computer was specially developed for this purpose. This now also allows use of raw data in the recon-struction process to further enhance image quality and reduce dose. In this way, users can take advantage of the potential for dose reduction in a notice-ably greater number of examinations during routine clinical application, signifi-cantly reducing the average dose. (For further information, see the article “Iter-ative Reconstruction Reloaded” on page 14 in this issue.) Using the potential of SAFIRE, 72% of all Siemens standard pro-tocols apply dose of below the average annual natural background radiation of 2.4 mSv.*** Michael Lell has performed clinical studies with the previous version of the software. He describes the results: “For research purposes, we always perform both the standard reconstruction and the iterative reconstruction. With the previ-ous algorithm, iterative reconstruction takes about four to five times longer than standard reconstruction. Here, I expect a clear improvement with the new algo-rithm. With the previous algorithm an abdominal CT can be performed using half the dosage without compromising image quality. Our work on thoracic CT has not yet been concluded, but the potential for dosage reduction is ex pec-ted to be of a similar order of magni-tude. These are considerable reductions of dose that should be used. If the new algorithm is faster and offers better image quality, it is ready for routine application.” Optimal scan parameters for everyone When it comes to the sensitive issue of radiation exposure, Siemens follows the ALARA principle: “As Low As Reason-ably Achievable.” FAST CARE comes with CARE kV, an expansion of CARE Dose4D, which modulates the tube cur-rent according to the patient’s anatomy. In addition, CARE kV now automatically identifies the optimal tube voltage and adapts the tube current accordingly. This change is useful, for instance, when contrast agents are used. Because 2 “If the new algorithm is faster and offers better image quality, it is ready for routine application.” Michael Lell, MD, PD, Departement of Radiology, University of Erlangen- Nuremberg, Erlangen, Germany *** syngo.via can be used as a standalone device or together with a variety of syngo.via based software options, which are medical devices in their own rights. *** SAFIRE: The information about this product is being provided for planning purposes. The product is pending 510 (k) review, and is not yet commercially available in the U.S. *** Data on fi le.
- 9. 1 Manually settingthe scan range too short in the topogram can cut off relevant parts of the examined organ. 2 3 FAST Planning uses the defined anatomical landmarks to set the correct ranges. When applied manually without FAST CARE, only based on the coronal view the lower part of the lung could be easily be missed (indicated by the reference line). 4 Direct setting of the scan range in with FAST Planning assures covering the entire organ without overscanning SOMATOM Sessions · November 2010 · www.siemens.com/healthcare-magazine 9 the higher iodine contrast more than makes up for the higher absorption of iodine, a lower tube voltage can be applied. In this case, however, the mAs value should be adapted. This requires quite a bit of familiarity with the tech-nology. Many users are not confident enough to make that adaptation and therefore do not exploit the potential to be gained from changing the tube volt-age. CARE kV takes this insecurity out by preparing the appropriate kV and mAs value, thus taking the burden off the user. Also, CARE Dashboard can be used to display which dose-reducing mea-sures are available for the scan regions selected in the scanning protocol and whether these have been activated. Lell explains: “We have a legal and moral obligation to protect patients from unnecessary radiation. The Medical Ser-vice, tasked with providing the radiation protection of supervisors and physicians involved with suggestions for improving radiation protection, reducing radiation exposure and enhancing image quality, routinely checks whether we adhere to this obligation. CARE kV and CARE Dash-board give us further support in this area. Many users, however, do not use the available solutions consistently enough. Automation is useful, but we also need better training. The various options for dose reduction must be cho-sen suitably.” For instance, Lell has found that caution is required when using specific solutions on children. Therefore, new parameter sets were developed for CARE Dose4D that take into account the specific anatomy of the child. Also, the STRATON tube was developed further so that in case of pediatric scans, the voltage can be reduced to 70 kV. The issue of dose cannot be discussed independently of the diagnostic evalua-tion when it comes to CT. A clear deci-sion is always required as to when the clinical necessity of a CT examination is greater than the potential risks of radia-tion exposure. Lell believes dose can also be reduced by ensuring that the selected examination area is defined as narrowly as possible, which FAST CARE does automatically. Furthermore, the 1 2 Manually setting the scan range too long in the topogram could potentially over-radiate the patient 3 4
- 10. Coverstory 5 6 10 SOMATOM Sessions · November 2010 · www.siemens.com/healthcare-magazine requirements for image detail should be limited to what is necessary for resolving the problem at hand. In planning a lung biopsy, less detail is required than when searching for metastases. “Therefore,” emphasizes Dr. Lell, “all radiologists should ask themselves what degree of quality is in the best interests of the patient.” This, too, is an important con-tribution to reducing radiation exposure. Improving visualization and management of dose FAST CARE also offers a number of functionalities that serve to visualize the radiation given to the patient during the scan. Before the start of the exami-nation, CARE Profile displays the course of the dose to be applied according to the patient’s anatomy. The user can also determine reference values and upper limits for the individual protocols and request notification when the scan approaches these limits, as required under a new IEC standard. Furthermore, the software includes applications for quality control. Currently, the CTDIvol and DLP data specified in the patient protocol must still be entered manually into a quality control monitoring pro-gram. This is arduous and time-consum-ing work. FAST CARE stores the data into the DICOM Dose SR with CARE Analytics that then can be evaluated. Lell explains: “Automatic data export offers unforeseen opportunities for qual-ity control. It would be possible to review the average dosage distribution values for every day and to check which scans exceed or fall below a certain value. Currently, such a degree of quality con-trol is still unattainable.” 5 FAST Cardio Wizard: It is an intuitive guid-ance software, integrated in the Cardio workflow. 6 Anatomically correct spine reconstructions are typically very time con-suming proce-dures, as every spinal cord and disc needs to have an own recon layer depending on its individual position. With FAST Spine, these manual steps can be simplified to ideally just a single click. Assistant Professor Dr. med. Michael Lell studied at the University of Regensburg and Technische Universität München. He is specialized in diagnostic radiology. Currently, he is Senior Physician at the Institute of Radiology, Erlangen University Clinic, Erlangen, Germany, where he has been working since 1997. He was a visiting researcher at the David Geffen School of Medicine at the University of California, Los Angeles, and is a member of various national and international professional bodies. He is also a peer reviewer of several medical journals.
- 11. Coverstory Dr. HildegardKaulen is a molecular biologist. After sojourns at the Rockefeller University in New York and Harvard Medical School in Boston, USA, she has been working as a freelance sci-ence journalist for prestigious daily newspapers and science journals since the mid-1990s. SOMATOM Sessions · November 2010 · www.siemens.com/healthcare-magazine 11 Dr. Sodickson, in the past three years, concerns have been raised about cumulative exposure by repetitive CT imaging. How serious is the problem? SODICKSON: There is persistent contro-versy over the risk models that exist for radiation exposure of the magnitude used in CT. We attempted to quantify the levels of risk using the most common Linear-No-Threshold risk model used in the 7th Biological Effects of Ionizing Radiation (BEIR-VII) report. We studied 32,000 patients undergoing CT at our institution, using the BEIR-VII model to estimate cumulative cancer risks from CT exposures. We found that 7% of our cohort had undergone enough previous CT radiation exposure to increase their cancer risk by at least 1% or more above baseline. As a result, we believe that patients undergoing recurrent imaging over time warrant heightened radiation protection efforts. Many CT users don’t take full advan-tage of the available dose reduction tools and work with protocols that are not fully optimized. Is active assis-tance, such as that provided by FAST CARE, the key to a more universal adoption? SODICKSON: Active assistance is one of many excellent solutions. Any automa-tion that makes scanning easier and helps to create reproducible results across the wide range of patient sizes and technologist skill levels is extremely valuable. But we also need better default protocols that are dose-optimized and “We Need Better Default Protocols.” Dr. Aaron Sodickson, MD, PhD, Assistant Director of Emergency Radiology, Brigham and Women’s Hospital, Harvard Medical School, Boston, spoke to journalist Dr. Hildegard Kaulen for SOMATOM Sessions: robust in order to ensure adequate diag-nostic image quality for every patient. We need close collaboration between CT manufacturers, radiologists, technolo-gists, and medical physicists. By com-bining our different areas of expertise, we can best reach consensus about what works and what doesn’t, and what represents adequate image quality for the particular diagnostic task at hand. What are the essentials for a radiation risk assessment program? SODICKSON: We should routinely review the imaging history of our patients. We are working to implement a decision support system that alerts ordering phy-sicians in real time of the magnitude of a patient’s radiation risk. Our goal is to bring appropriate perspective to the risk/ benefit decision by providing the best risk estimates possible. We hope this will enhance an active and critical review of the imaging order and an assessment of how the scan fits into the longitudinal medical history of the patient. Will risk assessment interfere with the workflow and lengthen the deci-sion making and scanning process? SODICKSON: That depends on how it is implemented. We need solutions that create an efficient workflow without frustrating delays. Otherwise they might not be accepted in clinical routine. An exciting feature for dose reduction is lowering kV. You had the chance to test CARE kV, which is a part of FAST CARE. Did the tool meet your expecta-tions? SODICKSON: We assessed an early proto-type, which worked quite nicely. Based on the patient’s size, the system automat-ically suggests kV and effective mAs set-tings that minimize the applied dose without compromising image quality. This tool takes a great deal of guesswork out of low kV scanning, making it feasi-ble for all technologists. As Assistant Director of Emergency Radiology, where do you see addi-tional potential for increasing patient care further, besides the ever-present topic of continuous dose reduction? SODICKSON: We need dose-optimized default protocols that work in fast-paced, sometimes chaotic settings such as the ED, and can be used reliably by technologists of all skill levels. We need streamlined workflow to scan even our sickest patients with reliably low dose and high quality results every time. We need improved education to ensure that every user is aware of the excellent dose-reduction tools that are available, and knows how to use them correctly. And finally, we need improved methods to capture patient- and exam-specific dose information from every scan, both for real-time quality control and for longitudinal dose-monitoring efforts.
- 12. News CEO Corner:Excellence in Clinical Practice Excellence in Clinical Practice through innovation & responsibility remains the cornerstone of Siemens’ leadership in the CT medical imaging field. A constant source of strength as aging markets in industrial countries, and dynamic mar-kets in rapidly developing countries, demand better health care at lower cost. We help you meet these challenges in four key areas: ■ You can depend on us, as undisputed trendsetter in CT technology, for the industry’s fastest and healthiest single and Dual Source scanners – today and into the future. ■ To improve your clinical efficiency, we support you with workflow excellence, ease of use and high reliability. ■ As your caring partner, we maintain highest industrial standards in cus-tomer relationship & care. ■ To make state-of-the-art CT affordable – and financeable – for you, we have introduced the new Excel Editions of our highly efficient 16- and 64- slice scanners. Reducing our vision to its essence: As a caring partner of our customers, we create CT-innovations that lift clinical practice to a higher level of excellence and enable wide access to better patient care. Our ambitious global team contin-uously Working with syngo.via – an In-Practice Report Physicians and technologists at the department of radiology at the University of Pennsylvania Hospital (HUP) have been evaluating the syngo.via* software for two years now. Harold I. Litt, MD, PhD, assistant professor of radiology and chief of the cardiovascular imaging section, reports on his experiences with syngo.via in his daily routine. By Michaela Spaeth-Dierl, medical editor, Spirit Link Medical, Erlangen The Hospital of the University of Penn-sylvania has a reputation as a world leader in medical research and clinical care. Since 1765, it has been dedicated to the care of patients, the education of physicians and development and imple- mentation of new medical knowledge. HUP therefore seemed to be the right place to evaluate one of the first research systems of the new syngo.via software from Siemens, and the radiol-ogy department there has now been 12 SOMATOM Sessions · November 2010 · www.siemens.com/healthcare-magazine sets the trend in an always changing environment… providing answers for life. We are looking forward, that in the years ahead, you will continue to work with us in our efforts to uphold excellence in CT’s clinical practice. evaluating it for two years. All cardiovas-cular CT and MRI exams, neurovascular CT, and body CT studies requiring addi-tional processing (e.g. CT urography and colonography) are automatically routed to the syngo.via server, and six radiolo- Dr. Sami Atiya, CEO Business Unit CT, Siemens Healthcare, Forchheim, Germany
- 13. “Looking at curvedMPR’s used to take a lot of clicks and usually wasn’t worth it. Since you now get it automatically, I’m looking at them in almost every case.” Harold I. Litt, MD, PhD, Assistant Professor of Radiology and Medicine, Chief, Cardio vascular Imaging Section, Depart ment of Radiology, University of Pennsylvania School of Medicine, Philadelphia, PA, USA SOMATOM Sessions · November 2010 · www.siemens.com/healthcare-magazine 13 gists and four 3D technologists regularly work with the system. In his section, Harold Litt mainly interprets cardio-vascular studies with syngo.via. “With syngo.via, the daily routine has changed. Compared to a stand-alone workstation, a thin-client system like syngo.via* has benefits for both workflow and time,” he summarizes his experiences. A great advantage of syngo.via is the automated pre-processing. When a case is opened, many pre-processing tasks such as table removal, bone removal, curved planar reformatting, naming of vessels, ejection fraction calculations and orthogonal cuts are already done. So, the radiologists can start their inter-pretation immediately. “My experience with syngo.via* in car-diac CT is that the pre-processing of data is very accurate and requires few edits. This means fewer corrections and faster reading,” says Dr. Litt. Compared to other thin client technology, there are also differences. Previously the workflow involved the following: the data from the scanners was sent to dedicated workstations, where the cases were post-processed by dedicated 3D technol-ogists. The techs captured screenshots of their results, saving them on the PACS and manually transcribing any numeric results into a web-based system. Radiol-ogists would review the captured images on PACS, another workstation, or a thin-client system, then copy and paste results from the web-based system to their reports in the RIS. If the radiologist wanted to review the technologist’s work directly, it would mean a walk to the 3D lab and reloading the case on a workstation. Now, and in the future with syngo.via, all users access the same database. Technologists prepare the cases and forward their results to the radiologists through “shared reading.” Radiologists can start reviewing each case where they are sitting and do not need to walk to the workstations anymore, and tech-nologists no longer need to type their measurements into a separate system. Furthermore, syngo.via allows its users to load cases from different modalities such as echocardiography or CT angio-graphy. The series navigator shows all images related to the opened patient, so radiologists don’t have to search for the right series from the right patient in the entire patient list. “Concerning several of the dedicated features available, the right ventricular analysis (RVA) within the syngo.CT Cardiac Function – Right Ventricle** is very much appreciated.” says Harold I. Litt. “We study many patients with congenital heart disease as well as those undergoing electrophysiology ablation procedures. Being able to calculate RV ejection fraction without manual con-touring saves half an hour per case. Now you get the LV and RV wall motion analysis and EF automatically as soon as you open a case – without any waiting or interaction.” Experience that testers of syngo.via have gained in the department of radiology at HUP shows that the use of this software provides a simplification of clinical work-flows and time savings. News ** syngo.via can be used as a standalone device or together with a variety of syngo.via based software options, which are medical devices in their own rights. ** syngo.CT Cardiac Function- Right Ventricle is not commercially available in the US. Dr. Litt has received grant funding from Siemens for research related to this product.
- 14. News Iterative Reconstruction Reloaded For the fi rst time, SAFIRE* introduces the usage of raw-data information within iterative reconstruction for everyday use in clinical practice. By Jan Freund, Business Unit CT, Siemens Forchheim, Germany For quite some time, iterative recon-struction has been heavily discussed in the CT community as a highly promising method to achieve significant dose reduction without compromising image quality. Essentially, iterative recon-struction introduces a correction loop in the image generation process that cleans up artifacts and noise in low-dose images. The proposed approach is, that after the initial reconstruction using the weighted filtered back projection (WFBP), the measured data of the acquired image (in the so-called image space) is compared to the data (raw-it 1A 1B 1C 1D 14 SOMATOM Sessions · November 2010 · www.siemens.com/healthcare-magazine had to conquer the challenge of per-formance. In order not to do so at the expense of image quality – a “plastic-like” image impression was one of the major drawbacks of other solutions – Siemens found a smart alternative: The innovative first step was the recon-struction of a super-high resolution image that had virtually no image loss. This was achieved by not applying the filtering that typically reduced image noise, taking into account that the resulting image was then accordingly very noisy, but contained all inform-ation. The iteration loops to reduce the data). But until now, the implemen-tation of this method for clinical practice was limited as the necessary re-trans-formation of data from the image to the raw-data space was very time-consuming and the computational power required to make it feasible for everyday use was not available. Therefore, vendors found several different approaches to handle this limitation in their first individual solutions. The fi rst step – IRIS At RSNA 2009, Siemens introduced its solution – IRIS. Like all other vendors, 1A Plain FBP 1B Standard Siemens’ WFBP 1C IRIS 1D SAFIRE
- 15. SOMATOM Sessions ·November 2010 · www.siemens.com/healthcare-magazine 15 noise in the image were then per formed completely in image space, which was the key to achieve the recon struction performance and keep a well-known image impression. This unique approach then even found its way into the product name: IRIS – Iterative Reconstruction in Image Space. Several publications proved IRIS to be highly effective when it comes to reducing dose while main-taining diagnostic image quality. The University of Erlangen for example, achieved average dose reductions of 50%** for abdomen examinations by taking Dual Source datasets done with the SOMATOM Definition Flash and reconstructing the images based only on data from one source. The resulting images – now naturally utilizing only half the dose – showed the same image quality after being reconstructed with IRIS compared to those reconstructed without IRIS and utilizing the data from both sources. The next generation – SAFIRE But now, Siemens actually shifted into a higher gear and introduced the successor at this year’s RSNA: SAFIRE – (Sinogram Affirmed Iterative Recon struction)*. For the first time, the use of raw data (which is visualized in the so-called sinogram) is actually being utilized in the image im provement pro cess. Here, the current set of CT images is transformed back into raw data which models all relevant geo-metrical pro perties of the CT scanner. This step produces a CT raw-data set that again resembles a virtual CT system. By com paring the synthetic raw data with the acquired data, differences are identi-fied. This procedure can be regarded as validating (or affirming) the current images compared with the measured raw data. The detected deviations are then again reconstructed using WFBP, yielding an updated image. With this step, the images can be analy-zed, subtracting image noise from the previous images without loss of sharp-ness. The same applies for potential arti-facts that every vendor is confronted with when using the WFBP and which often remain in conventional CT images. Using multiple iterations of these steps, geo-metrical imperfections of the WFBP are corrected in addition to incremen tally reducing image noise. With this, SAFIRE – Sinogram Affirmed Iterative Recon struc-tion – can achieve a radiation dose re-duction of up to 60%** at improved image quality (contrast, sharpness and noise), even surpassing the already impressive image quality realized with IRIS. This amazing achievement resulted mainly from two measures: First, the algorithms used in the iterations were redesigned to make them more efficient. And second, new image reconstruction systems (IRS) – were developed and intro duced parallel now finally providing the compu tational means for the complex calculations required. SAFIRE of course also works with the former IRS but naturally at a reduced performance. With the new high performance IRS – the FAST IRS – the performance is en - han ced even further. The result: With SAFIRE, the potential to reduce radiation dose is up to 60%,** but at an signifi-cantly improved image quality. The big dif ference is now, that this potential is accessible to a much larger number of examinations, meaning that the average dose saving over all examinations will be significantly higher. Using the potential of SAFIRE* 72% of all Siemens standard protocols, apply dose of below the average annual natural background radiation of 2.4 mSv.** SAFIRE will be com mercially available for all SOMATOM Definition AS in March 2011 and for SOMATOM Definition Flash in May 2011. 2 Improved noise reduction and workflow with SAFIRE* 2 ** The information about this product is being pro-vided for planning purposes. The product is pend-ing 510 (k) review, and is not yet commercially available in the U.S. ** Results may vary. Data on file. News
- 16. Topic Flash Spiralfor Precise and Patient Friendly Transcatheter Aortic Valve Implantation (TAVI) Planning. By Peter Aulbach Business Unit CT, Siemens Healthcare, Forchheim, Germany Transcatheter heart valve implantation is considered a technology with enormous clinical potential. The percutaneous implantation of a pulmonary valve was reported for the first time in 2000. Since then, these procedures have recorded constant double-digit annual growth,1 since it presents a new option to candi-dates for whom conventional surgery was not suitable. Clinical needs and challenges The recent PARTNER trial, published in the New England Journal of Medicine,2 demonstrates that transcatheter aortic valve implantation (TAVI), in comparison with standard therapy, resulted in signif-icantly lower rates of death among those patients. Patients who undergo TAVI show a 45% reduction in the rate of death in comparison with those receiv-ing standard therapy. Exact knowledge of the aortic root anat-omy, including the proximal coronary arteries, and the entire aorta up to the femoral artery bifurcation, is necessary to allow accurate pre-procedural planning. After scanning with conventional proto-cols, CT imaging requires relatively large amounts of contrast which can be a prob-lem in older patients, especially those with concomitant renal disease. Prospec-tively triggered high-pitch Flash Spiral Dual Source CT (Flash Spiral), with up to 458 mm/s table feed, is able to obtain all important anatomic information in one single scan. Because of the extremely rapid data acquisition, completed in less than 2 seconds (Fig. 1B), the amount of contrast agent can be reduced signifi-cantly. In conventional aortic valve surgery, the access route to the aortic valve is stan-dardized. Normally the sizing of the utilized valve prosthesis is done directly under visual control at the surgical site. In contrast, in TAVI procedures all these points need to be meticulously addres-sed during pre-operative planning, since annulus size, access route or distance of the coronary ostia to the aortic root will influence the procedural strategy and the appropriate selection of the artificial heart valve. Moreover, large amounts of contrast agent have to be used in addition to the 16 SOMATOM Sessions · November 2010 · www.siemens.com/healthcare-magazine contrast exposure during the aortic valve implantation itself. In the TAVI population, more than 50% of patients show impairment of renal function (elevated serum creatinine levels). It is known that up to one third of all patients undergoing catheter-based aortic valve implantation develop acute renal failure in the shortly following post-operative course.3 Therefore the application of contrast dye needs to be reduced to a minimum. Benefi ts of Flash Spiral CT The latest Dual Source CT system, the SOMATOM Definition Flash, allows the use of prospectively triggered high-pitch spiral data acquisition, called Flash Spiral. This mode allows a significant reduction of radiation dose compared to other CT technologies. Effective radia-tion doses of only 3-5 mSv are now only needed to visualize all relevant thoraco-abdominal structures (Fig. 1). Even more importantly, within this patient population, this new scan mode allows an extremely rapid data acquisition in less than 2 seconds (other CT technolo- 1A 1B
- 17. Topic 1 80-yearold patient with severe aortic valve stenosis prior to trans-catheter aortic valve implantation (TAVI). Pre-procedural Flash Spiral angiography was performed using high-pitch spiral data acquisition pro-spectively triggered at 60% of the R-R interval (128 x 0.6 mm slices, 100 kV, 320 mAs, SOMATOM Definition Flash). For thoraco-abdominal angiography including the coronary arteries (Arrowhead) only 40 ml of contrast agent was used (flow rate 4 ml /s). Estimated effective radiation dose was 4.3 mSv. at a scan time of 1.7 seconds. Images show assessment of aortic annulus diameters in syngo.via (Fig. 1A dotted line) as well as distances between the aortic annulus and the coronary ostia. In addition, peripheral arteries have been evaluated for significant stenosis (Fig. 1B). The red arrow indicates an occluded iliac artery, making transfemoral access impossible here. The same data also shows pronounced calcification along the whole thoracic aorta (Fig. 1C). 1 Cardiovascular News, Transcatheter heart valve replacement: A European perspective, www.cxvascular.com, Jan 2010 2 Valve Implantation for Aortic Stenosis in Patients Who Cannot Undergo Surgery, N Engl J Med 2010 3 Aregger F, Wenaweser P, Hellige GJ, et al. Risk of acute kidney injury in patients with severe aortic valve stenosis undergoing transcatheter valve replacement. Nephrol Dial Transplant 2009; 24: 2175–2179. 4 Vahanian A, Alfieri OR, Al-Attar N, et al. Transcath-eter valve implantation for patients with aortic stenosis: a position statement from the European Association of Cardio-Thoracic Surgery (EACTS) and the European Society of Cardiology (ESC), in collaboration with the European Association of Percutaneous Cardiovascular Interventions (EAPCI). EuroIntervention 2008; 4: 193-199. 2 Up to 60% less contrast media by use of high-pitch spiral DSCT angio-graphy of the complete aorta – compared to other CT tech-nologies. Courtesy of University of Erlangen- Nuremberg, Erlangen, Germany 140 ml* 100 ml# SOMATOM Sessions · November 2010 · www.siemens.com/healthcare-magazine 17 gies need about 6–9 seconds). This per-mits a tremendous reduction of contrast agent by 50–60%, which is crucial for patients with renal insufficiency under-going a subsequent TAVI procedure. Compared to approximately 100–140 ml of contrast agent needed in the past for a CT angiography of the entire aorta, it is now possible to use only 40 ml (flow rate 4 ml/s) for the same examination, which poses a significantly reduced risk of Contrast Induced Nephropathy (CIN) in this patient population (Fig. 2). Accurate and fast planning with syngo.via The decision whether a patient is suit-able for a catheter-based procedure and the pre-operative planning with the selection of the access route are based upon results of the CT angiography. The size of the aortic annulus for selection of the valve prosthesis and the angulation of the invasive fluoroscopy which allows for simulating the optimal projection of the aortic valve during the TAVI proce-dure can be predicted from the same DSCT angiography data with the support of syngo.via.* This leads to further con-trast media savings during the invasive procedure since the syngo.via* software automatically provides the correspond-ing C-arm position. On the basis of this protocol and ana-tomical measurements by Flash Spiral CT, physicians are able to quickly per-form more patient friendly and precise catheter-based procedures. The time consuming planning of the procedure is very well supported by the many automated pre-processing steps in the new syngo.via* software which in early tests could show to reduce plan-ning time by more than 33% (10 min. versus 15 min.). In a nutshell: Flash Spiral and syngo.via In conclusion the Definition Flash, combined with the highly automated syngo.via* workflow modules, provide the most possible patient friendly and accurate pre-operation planning solution available. The high potential for cost reduction coming from fewer patients suffering acute CIN and therefore requesting less of the expensive aftercare is not yet taken into account herein. SOMATOM Definition Flash: www.siemens.com/SOMATOM-Definition- Flash CT Cardiovascular Engine: www.siemens.com/CT-cardiology Single-Source CT for Abdominal Aorta 160 140 120 100 80 60 40 20 0 *Loewe C, Eur Radiol 2010; #Wu W, AJR 2009; §Flash Thorax Protocol 40 ml§ Amount of Contrast Agent [mL] Single-Source CT for Triple Rule Out Dual Source CT SOMATOM Definition Flash 2 News * syngo.via can be used as a standalone device or together with a variety of syngo.via based soft-ware options, which are medical devices in their own rights. 1C
- 18. “I am happyand proud to embark on this initiative together with Siemens and my colleagues from around the globe in order to ensure that Siemens’ powerful tools for dose reduc-tion are used to their fullest extent.” U. Joseph Schoepf, MD, Medical University of South Carolina, U.S. Siemens Launches SIERRA, the Siemens Radiation Reduction Alliance SIERRA’s expert panel proposes its fi rst recommendations on patient care and radiation reduction By Stefan Ulzheimer, PhD, Business Unit CT, Siemens Healthcare, Forchheim, Germany In a continual commitment to patient care and radiation reduction in Com-puted Tomography (CT), Siemens Health-care has launched SIERRA, the Siemens Radiation Reduction Alliance and has established an expert panel to advance the cause of dose reduction in CT. The new Low Dose Expert Panel includes 16 specialists in radiology, cardiology and physics, who are internationally recog-nized for their publications on the sub-ject of CT dose. The panel’s objective is to generate proposals on how Siemens can continue to develop their technology and to help users better adapt their pro-cedures in order to bring about further dose reduction in CT. One of the most important suggestions from the first meeting of the Low Dose Expert Panel in May 2010 concerns methods to recog-nize and increase utilization in clinical practice of the many CT dose reduction technologies that are already available. Siemens will pursue the following, concrete, first recommendations together with its partners: Q To establish a baseline of dose levels for the 10 most commonly performed CT exams, the group agreed to estab-lish and contribute to an international, multi-institutional dose registry. Q The participating, renowned institu-tions will share their CT scan protocols for the 10 most commonly performed examinations on a central web site as a first step to promote best practice sharing in the field. Q Siemens will develop a dedicated low dose educational program in close collaboration with the involved insti-tutions. 18 SOMATOM Sessions · November 2010 · www.siemens.com/healthcare-magazine The Panel will meet twice a year to dis-cuss new ideas and investigate whether measures already agreed upon are hav-ing a positive impact. The next meeting takes place at RSNA 2010. www.siemens.com/low-dose-CT Current Members of SIERRA’s expert panel: Hatem Alkadhi, MD, University Hospital Zürich, Switzerland Christoph Becker, MD, Ludwig Maximilians University, Germany Elliot Fishman, MD, Johns Hopkins University, U.S. Donald Frush, MD, Duke University, U.S. Jörg Hausleiter, MD, German Heart Center, Munich, Germany Brian Herts, MD, Cleveland Clinic Foundation, U.S. Willi Kalender, PhD, Erlangen University, Germany Harold Litt, MD, PhD, Pennsylvania University, U.S. Cynthia McCollough, PhD, Mayo Clinic, U.S. Alec Megibow, MD, NYU-Langone Medical Center, U.S. Michael Recht, MD, NYU-Langone Medical Center, U.S. Dushyant Sahani, MD, Harvard Medical School, MGH, U.S. U. Joseph Schoepf, MD, South Carolina Medical University, U.S. Marilyn Siegel, MD, Mallinckrodt Institute of Radiology, U.S. Aaron Sodickson, MD, PhD, Brigham and Women’s Hospital, U.S. Kheng-Thye Ho, MD, Tan Tock Seng Hospital, Singapore
- 19. Siemens CT StrokeManagement Siemens Healthcare recently has started a new CT Stroke Management Online Resource for healthcare professionals highlighting new diagnostic opportunities by synergizing with latest Siemens CT scanners and post-processing solutions – Helping to Save Brain and Quality of Life. By Stefan Wünsch, PhD, Business Unit CT, Siemens Healthcare Forchheim, Germany SOMATOM Sessions · November 2010 · www.siemens.com/healthcare-magazine 19 When diagnosing and treating stroke patients, time is critical. Stroke is one of the diseases where diagnosis, prognosis and treatment drastically changes within a short period of time. Every minute in which a large vessel ischemic stroke is untreated, the average patient loses 1.9 million neurons, 14 billion synapses, and 12 km (7 miles) of axonal fibers. Each hour in which treatment fails to occur, the brain loses as many neuron as it does in almost 3.6 years of normal aging*. Therefore, the need for faster diagnosis and faster treatment is central to acute stroke management care. Providing the right information in every step of the treatment is crucial in order to save brain and thus save quality of life for stroke patients. Siemens CT Stroke Management moves beyond just ruling out the bleed by helping to establish a personalized treatment plan. Using the possibilities of extended brain coverage, Siemens has radically improved the stroke workflow uniquely adding value to stroke management. In order to share these approaches, Siemens has pub-lished a new information platform www. siemens.com/CT-stroke-management to share clinical outcomes. Dr. Schramm from the University of Göttingen, Ger-many, for example, shares his workflow www.siemens.com/CT-stroke-management of a certified stroke unit from the arrival of a stroke patient in the emergency department until the decision for further treatment is made together with the neurologist. In his institute, the door-to-needle time is less than 20 min. Further-more, leading stroke specialists share their experience and protocols in webi-nars and presentations. Trial versions are offered to Siemens’ customers to test the latest software solutions in stroke imaging in actual clinical practice. This campaign is meant to improve the knowledge of stroke diagnosis with extended brain coverage and Siemens CT solutions and is also designed to inte-grate experiences of other customers worldwide. If you are interested in sharing your results with other colleagues on this homepage, please contact stefan.wuensch@siemens.com * Time is brain-quantified. Saver JL. Stroke. 2006 Jan;37(1):263-6. News
- 20. News A PediatricBreakthrough: Automated Adaptation of CT Dose Levels If only Siemens could re-engineer people like it does CT scanners. For more than a decade, Siemens has been at the forefront of dose reduction in computed tomography. New technology is coming on the market at breakneck speeds, with each generation making scans safer and faster. By Ron French Dose levels of CT scans have fallen dramatically in recent years and will continue to drop with Siemens’ latest scanners. Yet even as CT scans become safer for patients, the variation of dose from facility to facility can still be unac ceptably high, says Dr. Marilyn Siegel, Professor of Radiology and Pediatrics at Washington University School of Medi cine in St. Louis, Missouri (USA) and Pediatric Radiologist at the affiliated St. Louis Children’s Hospital. Siegel is delighted at the advancements in CT technology, allowing individual organs to be shielded and automatically adjusting the dose level in real time as the patient moves through the scanner. That technology must now be coupled with education, to assure that radiolo-gists and technologists across the globe are aware of – and using – proper pro-tocols for each patient. A decade ago, the average CT dose was 15 to 20 mSv. As the use of CTs explod - ed (more than 70 million scans are per-formed annually in the U.S. alone), does it, or you move and you do it yourself,” Siegel explains. “Siemens”, she adds, “has been at the forefront of dose reduction”. SOMATOM Defi nition AS: The Adaptive Scanner At St. Louis Children’s Hospital, the volume of CT scans is declining, but it is still the tool of choice for many neuro-lo gical exams, chest and abdominal scans including lung transplants, tumors, trauma and abscess infection. To limit radiation exposure, the hospital invests in the latest CT technology. The newest scanner at St. Louis Children’s Hospital is a SOMATOM Definition AS. The AS is the first scanner to intelligently adapt to the patient, changing dose levels automatically as it scans thicker and thinner parts of the body. Instead of setting a dose level that will offer clear images in a thick part of the body such as the shoulders and maintaining that level throughout the scan, dose levels rise and fall throughout the scan. radiation exposure to the population, especially in industrialized countries, increased. The National Council on Radiation Protection and Measurements reported in March 2009 that radiation exposure per capita more than doubled in the United States in the past two decades, largely due to increased use of CT, nuclear medicine imaging and interventional radiology. Because the potential risk of repeated radiation exposure accumulates over time, and because the tissues of children are particularly sensi tive to radiation, dose levels are an even bigger concern for pediatric radiologists like Siegel. “Effective dose in children is 3–5 times greater than in adults at comparable exposure levels, and you have very sensitive tissues, especially the breasts and gonads, in children who are growing,” Siegel clarifies. “The younger the patient, the more is the potential risk from radiation. There are two things you can do when there is a challenge: You can hide and hope somebody else “Siemens has been in the forefront of dose-reduction.” Marilyn J. Siegel, MD, Pediatric Radiologist, Washington University School of Medicine and St. Louis Children’s Hospital, Missouri, USA
- 21. SOMATOM Sessions ·November 2010 · www.siemens.com/healthcare-magazine 21 The Definition AS also reduces dose level in spiral scanning by eliminating radia-tion in pre- and post-spiral areas that won’t be reconstructed. Siegel watches on a computer monitor as a CT scan is performed on a young cancer patient. “Before, we’d set one dose level for the entire body,” Siegel says, “a dose level high enough for good image quality in the thickest part of the body. Now, the automated adaption of dose level cuts radiation.” The scanner also incorporates an Adap-tive Dose Shield to limit radiation to cli nically relevant parts of the body. The result is an average dose of 2 mSv to 3 mSv in young pediatric patients, a 10- fold decrease in dose from a decade ago. Though the St. Louis Children’s Hospital installed the SOMATOM Definition AS in January 2010, the hospital already has on order the next generation of Siemens CT scanner – the SOMATOM Definition Flash. The Flash will offer scans at less than 1 mSv – possibly as low as 0.5 mSv. “That’s incredible,” Siegel explains. “With the Flash, we can lower the dose without the need of sedation for patients under five (because of the speed of the scan). “It’s a win-win situation. The older scanners – yes, they were fast, and yes, you could reduce the dose, but not like you can now,” Siegel says. “It’s really about patient care and affecting patient outcomes, reducing the risk, and in creasing the benefit for these kids.” Siegel also published groundbreaking work on how dose can be reduced, especially in children and small patients, by not only adapting the tube current but also the tube voltage. Siemens has been providing dedicated pediatric pro-tocols using low tube voltages of 80 kV since 2002 but now they take this method to the next level. The latest scanners will come with CARE kV, a fea-ture that automatically recommends the ideal tube voltage for the individual. Additionally, Siemens will be the first CT vendor to offer a tube voltage setting of 70 kV which allows for additional dose savings in the youngest patients. Education and certifi cation is key Siemens’ willingness to listen to the needs of physicians and continue to improve their scanners is why Siegel’s pediatric radiology department uses Siemens equipment. Siegel was instrumental in the develop-ment of CT protocols for Siemens, and serves on an expert panel organized by the company to brainstorm ways to reduce dose levels in CT. “One of the things that we discussed and that Siemens already implemented is a warning system that alerts the user if certain pre-set dose limits are exceeded,” Siegel emphazies. “If you choose a protocol and it’s really way off, you get a warning to reconsider your choices.” Siegel does CT accreditation for the American College of Radiology. “I am sometimes surprised at what I see out there,” she says. There is a lot of varia-tion in radiation dose among sites. One published study found a dose variation of 13-fold. “There is a lot of education to do, not only for radiologists but also technologists,” Siegel says. “We know we’re not there yet, but we’re making progress.” Newer dose reduction scanner technology is one part of the solution for dose reduc-tion, Siegel says, but another important factor is education. Siegel is sold on Siemens scanners, but also on the com-pany’s commitment to education. Siemens personnel are always available to answer questions and have helped train the hospital’s technologists. While the number of CT scans continues to rise for adult patients, scan levels have stabilized among children and are actually going down at academic centers such as St. Louis Children’s Hospital. Siemens has been a pioneer in reducing CT dose level for more than a decade, with each new generation of scanners breaking barriers. At St. Louis Children’s Hospital, Siemens helps train technolo-gists to operate the scanners in ways to get the best possible images and keep radiation dose as low as reasonably achievable (the ALARA principle), which is what is all about when scanning children. What’s the future for pediatric radiology at St. Louis Children’s Hospital? Faster scans. Safer scans. Lower radiation doses. More arm-in-arm innovation with Siemens. “I feel like I’m lucky to work with them,” says Siegel. Ron French is a healthcare writer based in Detroit, Michigan (USA). 1 6 weeks old pediatic case after congenital heart surgery (utilizing 3 mSv) 1 News
- 22. Topic Expanding Radiodiagnostics:University Hospital Hradec Králové, Czech Republic The University Hospital in the Czech district capital Hradec Králové has been able to increase its radiodiagnostic activities considerably, thanks to the installa-tion of a Siemens CT scanner from the SOMATOM Emotion 6 range. Dr. Pavel Ryska, principally highlights the device’s performance: reliability, application range and image quality. By Rudolf Hermann With 23 clinical departments, 1,500 beds and an annual volume of around 40,000 patients, the University Hospital (Fakultni nemocnice) in Hradec Králové, the capital of Eastern Bohemia, is one of the most important healthcare facilities in the Czech Republic. Although, as a university hospital, research forms a prime focus of activity, the establish-ment also fulfills the function of a general hospital as Hradec Králové has no separate city clinic. This results 22 SOMATOM Sessions · November 2010 · www.siemens.com/healthcare-magazine in slightly different requirements and prerequisites in the day-to-day running of the hospital, setting it apart from traditional university hospitals which are not obliged to fulfill this additional function. Dr. Pavel Ryska performs up to 40 patients a day on the SOMATOM Emotion 6.
- 23. market for self-payingprivate patients is virtually non-existent and it is thus impossible to receive extra remuneration for additional services. The SOMATOM Emotion 6 CT scanner’s increased efficiency over its HiQ predecessor is used primarily for better, more complex diagnostic assessments as opposed to more examinations. “We could certainly utilize another CT device to capacity on the basis of potential patient figures alone. At present, we treat patients from our catchment area only. The SOMATOM Emotion 6 is so efficient that we are able to reduce waiting periods for examina-tions during day-to-day operations”, says Dr. Ryska. Indispensable workhorse Ryska believes that, as a university hospital, his establishment should be at the forefront of technical progress. However, he knows only too well that, the Czech healthcare system has limited resources. With its excellent speed- and examination quality ratio, the highly efficient SOMATOM Emotion 6 blends into this medical landscape with con-summate ease. In fact, it could be termed the indispensable workhorse, while the Definition AS+ is called on to perform more challenging tasks. A particular benefit of the CT devices at the hospital in Hradec Králové high-light ed by Ryska is the variable and therefore reduced patient radiation exposure, achieved by state-of-the-art technology (ultra-fast ceramic detectors and CARE Dose4D technology). Exposure is reduced by between 30 and 40 per-cent on average in comparison with earlier models. Physicians are particularly pleased by this development since patients do not tend to address the issue as frequently. However, parents of children undergoing examinations are displaying increasing interest in the ques tion of radiation exposure. Improvements made via the use of the SOMATOM Emotion 6 Clinical: Q broader, more complex diagnostics for routine examinations Q a clear reduction in radiation dose by an average of 30–40% Workflow: Q its outstanding capability to combine high througput with high quality for a large range of applications makes the SOMATOM Emotion 6 a “workhorse” for the majority of mainstream exami-nations Q a user-friendly interface permits synergies with other radiological facilities at the hospital Q high system reliability without signif-icant downtime or maintenance periods Patient contact: Q the highly efficient SOMATOM Emotion 6 allows patient needs at a public hospital funded by health insurance firms to be met to the required quality standards without significant waiting periods. Rudolf Hermann is a journalist based in Prague with extensive experience of political and economic developments in Central and Eastern Europe. SOMATOM Sessions · November 2010 · www.siemens.com/healthcare-magazine 23 The radiodiagnostics department at Hradec Králové has been using a Siemens SOMATOM Emotion 6 CT scan-ner for around six years. The scan ner replaced a previous model, also by Siemens, from the HiQ range. The hospital also recently installed another CT scanner the SOMATOM Definition AS+, which is used in the emer gency depart-ment. Highly cost-effective According to Dr. Pavel Ryska, responsible for the SOMATOM Emotion 6, the deci-sion to purchase Siemens scanners was based both upon positive experiences with the previous range and on the high service level offered. Ryska values the Emotion 6 range as it facilitates a high examination density in line with manda-tory medical standards for a large num-ber of applications, making procedures extremely cost-effective. Moreover, the device is easy to install and has no specific spatial demands. In Ryska´s view, a further benefit is the system’s reliability, which results in high eco-nomic efficiency. The head of department particularly appreciates the syngo user interface, which not only facilitates fast orienta-tion, but also functions in a manner similar to other radiological devices from the same manufacturer (such as magnetic resonance), with the result that staff from other departments quickly become familiar with its operation (so-called multi-modality workplaces). In the light of the fact that Czech hospitals conclude fixed fee contracts with health insurance providers, the “The scanner is an indispensable workhorse. We examine up to 40 patients a day with 30–40% lower dose on average than before.” Dr. Pavel Ryska News
- 24. News Full CardiacAssessment with syngo.via – Maximal Signifi cance, Minimal Dose Siemens has once again succeeded in taking another step forward in the fi eld of CT diagnostics. By combining SOMATOM Scanners with the new syngo.via** imaging software, cardiac function assessments can now be carried out using very low radiation doses. By Michaela Spaeth-Dierl, medical editor, Spirit Link Medical, Erlangen Assessment of cardiac function with CT is still a challenging procedure for radio-logists. Siemens has now managed to solve some critical issues. A full cardiac function evaluation requires multi-phase CT data which previously led to high patient doses. Engineers at Siemens took up the chal-lenge. Aiming at turning a difficult pro-cedure into a routine task, they devel-oped MinDose and syngo.CT Cardiac Function*. MinDose – about 50% reduc-tion of radiation exposure Conventional ECG multi-phase datasets are usually acquired with a radiation dose of 8–10 mSv. MinDose mode has now reduced this dose by half. This means that a full cardiac function assessment is available with approx. 4 mSv. The dose-saving effect of MinDose mode is achieved by ECG-controlled tube current modulation. Sharp images are most likely to be obtained during the diastolic phase, when there is mini-mal movement in the heart. Therefore, the tube output is raised to the maxi-mum level during these intervals. During the remaining, predominant phase of the cardiac cycle, the tube current can be reduced to 4%. This is a unique plus for Siemens tubes since other tubes only allow a current de - crease down to 20%. 24 SOMATOM Sessions · November 2010 · www.siemens.com/healthcare-magazine This benefit, however, can only be achieved by combining SOMATOM CT scanner MinDose data with syngo.CT Cardiac Function,* an application run-ning on the basis of the syngo.via** imaging software. syngo.CT Cardiac Function optimally handles MinDose data During a multi-slice CT examination of the heart, large amounts of data are obtained, but only very few of them are used for image reconstruction. With the new syngo.CT Cardiac Function, it is now possible to use MinDose data for a full functional assessment. The syngo.CT Cardiac Function software Evaluation of cardiac function based on high quality images.*
- 25. The assessment ofcardiac function also works with noisy MinDose images. (30% dose savings in comparison with normal ECG Pulsing with 20% plateau)* “Having the possibility to quantify and evaluate a stenosis with one click while moving through axial slices tremendously improves my workfl ow.” Prof. Stephan Achenbach, MD, Erlangen University Hospital, Erlangen, Germany 17 manual steps with a single click and to complete a full cardiac assessment within four minutes. SOMATOM CT scanners with syngo.via – more than the sum of its parts The combination of Siemens SOMATOM CT scanners and syngo.via** adds a new dimension to cardiac assessment. For the first time ever, radiologists can perform full, highly precise “zero click” News SOMATOM Sessions · November 2010 · www.siemens.com/healthcare-magazine 25 defines “landmarks” in images taken during a diastole and adapts these ana-tomic regions for images taken during other phases of the cardiac cycle. These intelligent algorithms can perform highly reliable cardiac anatomy seg-mentation even with noisy low-dose data. So in effect, not a single image is wasted. CT Cardio-Vascular Engine offers automated workfl ows Siemens looked at the concerns of SOMATOM CT users and has also addressed clinical challenges such as time management, cost pressure and work sharing. Based on syngo.via,** Siemens has released a completely ren-ewed CT Cardio-Vascular Engine that almost entirely automates clinical work-flows. Radiologists can immediately start diagnosing – thanks to automated performing pre-processing, the clear arrangement of physiological parame-ters. In cardiac function evaluation, these pre-settings and supportive evaluation tools enable the user to skip full cardiac assessments with MinDose CT data. This unique combination allows them to reduce the dose by up to 50% and to save a great amount of time and effort. Thus, workflow optimization has been taken a step further – benefitting both the radiologist and the patient. ** syngo.CT Cardiac Function – Right Ventricle is not commercially available in the US. ** syngo.via can be used as a standalone device or together with a variety of syngo.via based software options, which are medical devices in their own rights.
- 26. News 26 SOMATOMSessions · November 2010 · www.siemens.com/healthcare-magazine Advanced Imaging for Four-Legged Patients Installing the SOMATOM Spirit has brought a new level of patient care to Croft Veterinary Hospital in Cram-lington, Northumberland, UK, while also increasing referrals. By Sameh Fahmy In the same way that tertiary care hospi-tals provide the most advanced medical care for humans, Croft Veterinary Hospital in Cramlington, Northumberland, UK, provides companion animals with specialized care using state-of-the-art equipment. Co-founder Malcolm Ness, BVetMed, says that he and his col-leagues wanted to build a referral center where patient care would not be com-promised by technological limitations. This is why they chose to install Siemens SOMATOM Spirit multi-slice CT scanner when they moved to a new and larger facility in 2008. “We just wanted to do things better and to continue to improve, largely for the good of the patients, but also for our own academic and intel-lectual satisfaction,” Mr. Ness says. While the use of CT in veterinary prac-tices is still relatively rare, Mr. Ness explains that the Spirit technology has allowed him and his colleagues to work more efficiently while improving patient outcomes. Metastases from mammary cancers in dogs that were once visual-ized with conventional radiography taken from three different views are now rapidly imaged using CT. Mr. Ness points out that, in addition to saving time, CT is much more sensitive and routinely detects tumors less than 1 millimeter in diameter. “Cases that were really quite complex and challeng-ing from a diagnostic imaging point of view are now very straightforward, quick and affordable,” he says. Planning spinal surgeries using radiographic myelography used to require multiple views and routinely took up to an hour, whereas a single CT myelography scan can give surgeons all of the information they need in minutes. CT also improves surgical planning for severely commi-nuted fractures and allows for the visual-ization of stress fractures in complex anatomy, such as the hock (the equiva-lent of the human ankle) in greyhounds. One feature of the Spirit that is parti-cularly useful, Mr. Ness reports, is the ability to create three-dimensional reconstructions almost instantaneously. In addition to helping plan surgeries such as pelvis reconstruction following a vehicle collision, three-dimensional images allow him and his colleagues to better communicate treatment needs and goals to their clients, the pets’ own-ers. He says the Spirit offers the ideal combination of image quality, reliability and ease of use. Leasing through Siemens Financial Services allowed Mr. Ness to reduce his upfront financial investment and made it easier to plan his cash flow, and his investment has already resulted in increased referrals. “We get a number of cases specifically because we have the CT,” Mr. Ness says, “and when we’re out talking to referring veterinarians, they never cease to be amazed by the images and are intensely jealous of the fact that we have something that can give us such brilliant pictures at the drop of a hat.” Sameh Fahmy is an award-winning freelance medical and technology journalist based in Athens, Georgia, USA In 2008 Croft Vets has opened the doors to its state-of-the-art flagship veterinary hospital.
- 27. * The informationabout this product is being provided for planning purposes. The product is pending 510 (k) review, and is not yet commercially available in the U.S. Among Europe’s Best By Doris Pischitz, Corporate Communications, Siemens Healthcare, Erlangen Germany www.siemens.com/healthcare-magazine www.siemens.com/healthcare-eNews SOMATOM Defi nition AS Open* – Dedicated High-end CT for Radiation Therapy Planning By Jan Freund, Business Unit CT, Siemens Healthcare, Forchheim, Germany News SOMATOM Sessions · November 2010 · www.siemens.com/healthcare-magazine 27 At this year’s annual meeting of the American Society for Therapeutic Radio-logy and Oncology (ASTRO), Siemens introduced the new SOMATOM Defini-tion AS Open* – the first and only dedi-cated, high-end CT system to efficiently cover both diagnostic radiology and Radiation Therapy (RT) needs. Because of its base in diagnostic CT, it delivers cut-ting edge radiation image quality. In RT, a precise diagnosis and location of the tumor is key to an accurate planning, positioning of the patient and finally to a successful therapy. For example, the capability to freeze motion is of highest importance in order to easily and accu-rately contour the tu mor. The SOMATOM Definition AS Open is now a fully dedi- Siemens Healthcare Publications received the Silver Award in the category “Best Crossmedia Solution” at the BCP Best of Corporate Publishing Congress in Ham-burg, Germany. Under the topic “Health-care Publications,” Siemens Healthcare submitted its crossmedia publications portfolio, which consists of the business-to- business magazine Medical Solutions, the expert magazines SOMATOM Sessions (computed tomography), AXIOM Innova-tions (angiography, radiography, and flu-oroscopy), MAGNETOM Flash (magnetic resonance imaging), Perspectives (labora-tory diagnostics), and the Healthcare Newsletter. The new SOMATOM Definition AS Open* with its extra large bore. Siemens Healthcare offers a variety of publica-tions tailored to the customers’ needs. cated RTP system due to its new, specific RT options and modifications: its bore diameter was increased to 80 cm. Next to the regular Field of View (FOV) of 50 cm and the extended FOV of 80 cm, it now also features an innovative High- Definition (HD) FOV of 65 cm delivering the required accuracy to reliably plan radiation treatments. The dedicated, multi-purpose table offers a patient load capacity of 227 kg with a deflection of less than 2 mm and the new Reference- Fix function takes care of aligning the relation bet ween the different coordi-nate systems of the CT system and the Linac. And even more so, the SOMATOM Definition AS Open is available as a slid-ing gantry solution,* so that the patient can be kept on the table at all times. In addition, Tspace View allows proper motion management for safe, fast and easy contouring for non-gated conven-tional treatments and an open interface for respiratory gating is also available. The SOMATOM Definition AS Open will be available starting March 2011. The jury of the largest corporate publish-ing contest in Europe honored the best publications out of over 600 entries. We hope you are just as satisfied with our media as the jury. Don’t hesitate to tell us your opinion at editor.medicalsolutions. healthcare@siemens.com. If you would like to subscribe to any of our periodicals, please visit our websites.
- 28. SOMATOM Scanners Aheadof the Innovative Curve New Siemens technologies in Computed Tomography lead to a wider spectrum of indications, providing additional infor-mation for generating a more precise diagnosis. Advantages of these new developments have been scientifi cally validated: “Investigative Radiology” published two special issues dedicated to “Advances in CT Technology”. By Heidrun Endt and Stefan Ulzheimer, PhD , Business Unit CT, Siemens Healthcare, Forchheim, Germany “Investigative Radiology,” a world-renowned journal, published two special issues in June and July 2010 titled, “Advances in CT Technology”. In these two special issues, 16 out of the 21 studies were done on SOMATOM Scan-ners which once more exemplifies Siemens continuous commitment to improve patient care and highlights Siemens innovation leadership. Perfusion Imaging and CT – Angiography The Adaptive 4D Spiral allows for whole organ perfusion studies and long-range, phase-resolved CT-Angiography (CTA). In a phantom study, the tissue flow values measured with the use of the Adaptive 4D Spiral correlated very well with those measured with the standard dynamic scan modes.1 Morhard et al. from Gross-hadern, Munich report on the advantages of the Adaptive 4D Spiral for brain perfu-sion CT with the SOMATOM Definition AS+ in 72 patients. The coverage was extended to 9.6 cm. Using this new tech-nique, “resulted in a different final diag-nosis in 34.7% of all exams”2 and “led to an augmentation of clinically important information in the imaging of acute stroke.”2 Helck et al. assessed morphology and function in kidney grafts with the SOMATOM Definition AS+ simultane-ously. 3 Qualitative and quantitative per- 28 SOMATOM Sessions · November 2010 · www.siemens.com/healthcare-magazine 1 Dual Energy CT provides all the infor-mation needed for the characterization of renal masses in a single-phase scan. Diagnosis of angiomyolipoma in the left kidney: 1A: information of both tubes; 1B: virtual non-contrast image; 1C: iodine image; 1D: overlay of B and C fusion information was acquired in 21 patients with liver metastases by researchers from Zurich with the SOMATOM Definition AS and the SOMATOM Definition Flash.4 A future indication could be the evaluation of perfusion patterns after anti-angio-genetic treatment. Dual Energy CT Dual Energy CT (DECT) allows for the acquisition of a virtual non-enhanced image and an iodine image with a single scan, whereas the conventional method would need a dual-phase scan: a true non-enhanced scan and one with the application of contrast media. Research-ers from Grosshadern, Munich evaluated CT examinations of 202 patients with renal masses comparing these two exam-ination modes. “DECT allows for fast and accurate characterization of renal masses in a single-phase acquisition.”5 A total radiation dose of 4.95 mSv was applied for the DECT enabling a “48.9% ± 7.0% dose reduction over the dual-phase pro-tocol.” 5 The Selective Photon Shield for the SOMATOM Definition Flash makes an News 1B 1D 1A 1C
- 29. 1 Haberland U.et al. Performance assessment of dynamic spiral scan modes with variable pitch for quantitative perfusion computed tomogra-phy. Invest Radiol. 2010 Jul;45(7):378-86. 2 Morhard D. et al. Advantages of extended brain perfusion computed tomography: 9.6 cm coverage with time resolved computed tomography-angiog-raphy in comparison to standard stroke-computed tomography. Invest Radiol. 2010 Jul;45(7):363-9. Dual Energy CT with the SOMATOM Defi nition on the Cover of “Radiology” By Heidrun Endt and Bernhard Krauss, Business Unit CT, Siemens Healthcare, Forchheim, Germany A new approach to bone imaging with Dual Energy CT on the SOMATOM Definition is shown on the cover of “Radiology”, August 2010. SOMATOM Sessions · November 2010 · www.siemens.com/healthcare-magazine 29 A new approach to bone imaging with Dual Energy CT (DECT) is reported in an article published in the August 2010 issue of “Radiology”. The internationally recognized journal chose the cover image for this issue from the study done by Pache et al. on the SOMATOM Definition.1 Researchers from Freiburg revealed specific lesions of the bone marrow, also known as bone bruise, with a DECT virtual non-calcium technique. Until now, the diagnosis, “bone bruises,” was acquired only from magnetic reso-nance (MR) imaging. Bone bruise is dis-cussed, “to predict associated soft-tissue injuries”1 and to, “be a precursor of early degeneration changes.”1 Twenty-one patients with acute knee traumas, were scanned with an MR as well as a DECT scan. The applied post-processing algorithms enabled the scientists to subtract calcium from the DECT images so that the marrow space of the bones could be assessed. The authors concluded that DECT ”might constitute an option for those patients who have contraindications to MR imaging or for whom MR imaging will not be available”.1 Potentially, “other pathologic processes (...), such as meta-static spread, could also be detec ted by using DECT with higher accuracy or in earlier stages than with single-energy CT alone.”1 This study shows once again that Dual Energy CT on SOMATOM Scanners pro-vides a lot of new possibilities waiting to be discovered. 1 Pache G. et al. Dual-energy CT virtual noncalcium technique: detecting posttraumatic bone marrow lesions-feasibility study. Radiology. 2010 Aug; 256(2):617-24. improved separation of the energy spectra possible and allows for DECT scanning with-out additional dose. With this technique Thomas et al. from Tuebingen differentiated urinary calculi reliably, while Dual Energy con-trast was increased.6 The authors suggest: “Also other applications as bone and plaque removal from DECT-angiographic datasets can be expected to benefit (…) because a higher DE contrast will be advantageous for the sep-aration of iodine and calcium.”6 Myocardial Perfusion Myocardial perfusion imaging is one indica-tion to which the spectrum of Computed Tomography is extended due to the innova-tive technology of the SOMATOM Definition Flash. Mahnken et al. from Aachen report on initial experience in “quantitative whole heart stress perfusion CT imaging”7 in an animal model. They assume that “this technique is able to show the hemodynamic effect of high grade coronary stenosis”7 and that “it exceeds the present key limitation of cardiac com-puted tomography.”7 First clinical experience is shown in a study by Bastarrika et al.: http://journals.lww.com/ investigativeradiology http://radiology.rsna.org/ content/256/2.toc Scanning with the SOMATOM Definition Flash allows for “the evaluation of quali-tative and semi quantitative parameters of myocardial perfusion in a comparable fashion as with MRI.”8 Outlook Further publications are expected to come, showing how these new tech-niques are applied in clinical practice. The editors of these two special issues are convinced and conclude: , “For sure, innovative research on imaging technol-ogy (…) will contribute to advances in clinical medicine and patient care.”9 Siemens Computed Tomography will proceed and will stay committed to its innovation leadership. 3 Helck A. et al. Determination of glomerular filtra-tion rate using dynamic CT-angiography: simulta-neous acquisition of morphological and functional information. Invest Radiol. 2010 Jul;45(7):387-92. 4 Goetti R. et al. Quantitative computed tomogra-phy liver perfusion imaging using dynamic spiral scanning with variable pitch: feasibility and ini-tial results in patients with cancer metastases. Invest Radiol. 2010 Jul;45(7):419-26. 5 Graser A. et al. Single-phase dual-energy CT allows for characterization of renal masses as benign or malignant. Invest Radiol. 2010 Jul;45(7):399-405. 6 Thomas C. et al. Differentiation of urinary calculi with dual energy CT: effect of spectral shaping by high energy tin filtration. Invest Radiol. 2010 Jul;45(7):393-8.) 7 Mahnken AH. et al. Quantitative whole heart stress perfusion CT imaging as noninvasive assessment of hemodynamics in coronary artery stenosis: preliminary animal experience. Invest Radiol. 2010 Jun;45(6):298-305. 8 Bastarrika G. et al. Adenosine-stress dynamic myocardial CT perfusion imaging: initial clinical experience. Invest Radiol. 2010 Jun;45(6):306-13. 9 Fink C. et al. Advances in CT technology. Invest Radiol. 2010 Jun;45(6):289. News
- 30. Business 1,000th SOMATOMDefi nition AS Installed – A Success Story Following its introduction at the RSNA 2007, the fi rst SOMATOM Defi nition AS was installed in May 2008. Since then, this unique, single-source CT system – the world’s fi rst Adaptive Scanner – has written an unparalleled success story. In September 2010, it was crowned with the 1,000th installation. And there are many more to come. By Jan Freund, Business Unit CT, Siemens Healthcare, Forchheim, Germany The updated appearence of the new SOMATOM Definition AS, now with a clear resemblence that it inherited together with multiple features from the SOMATOM Definition Flash.
- 31. Business Right afterits introduction, the manufacturing lines of the SOMATOM Definition AS were filled and have remained filled since then. SOMATOM Sessions · November 2010 · www.siemens.com/healthcare-magazine 31 With the introduction of the SOMATOM Definition AS – the world’s first Adaptive Scanner – in 2007, Siemens opened a new chapter in single-source CT tech-nology. The revolutionary idea was to combine high-end CT imaging for any clinical task at lowest possible dose with a scanner design that didn’t exclude patients because of the system’s geome-try. And all this with a footprint small enough to fit it into literally minimum space. The result: for the first time, a system actively adapts itself to virtually every clinical situation. Offering a 128- slice CT system with a pitch-independent isotropic resolution of 0.33 mm, a rota-tion time of 0.3 seconds and 100 kW generator power, it delivers enough reserves to meet virtually all clinical tasks. With a 78 cm bore diameter, a scan range of 200 cm that can be acquired in approximate 10 seconds at highest reso-lution and a table load capacity of up to 300 kg, whole body examinations in acute care or bariatric imaging were turned into clinical routine. Groundbreak-ing innovations introduced new dimen-sions in CT: the Adaptive 4D Spiral over-came the limitations of a static detector design and allowed covering whole organs in 4D – and the still unique 3D interventional suite provided 3D guided intervention support. This was all realized within a system that could be fit nearly everywhere with only an 18 m² footprint, freely selectable air or water cooling and full on-site upgradeability. After the first installations, users were immediately excited. Among the first was Prof. Joe Schoepf from the Medical Uni-versity of South Carolina. In an interview, he commented that the “Definition AS will effectively overcome a number of limitations we face today. […] All the guess work is taken out” and it “has all the power […] to capture clear images unmarred by excess noise, even in obese patients.” Following this excitement, many publications proved that the SOMATOM Definition AS kept the prom-ises given. In 2009, a new software ver-sion was rolled out to all customers, underlining Siemens’ dedication to cus-tomer care. With innovative features like Neuro BestContrast, it boosted the already outstanding image quality even further and made IRIS – the Iterative Reconstruction in Image Space – avail-able for the SOMATOM Definition AS. Naturally, this convinced the market and the result was the fastest ramp-up in Siemens CT’s history. After the first installation in May 2008, the SOMATOM Definition AS surpassed 500 installations, in September 2009, and then achieved the 1,000th installation in September 2010 in Washington DC, USA. Now, Siemens has taken the SOMATOM Definition AS to the next level with the introduction of FAST CARE at this year’s RSNA. For decades, Siemens has spear-headed dose reduction and has intro-duced many innovations following the “As Low as Reasonably Achievable” (ALARA) principle. For this, Siemens’ initi-ated its CARE (Combined Applications to Reduce Exposure) philosophy more than 15 years ago. Additionally, the SOMATOM Definition AS brought many innovations like the Adaptive Dose Shield that, for the first time, virtually eliminated unneces-sary over-radiation in every spiral scan. The new FAST (Fully Assisting Scanner Technologies) philosophy now aims to give customers the possibility to maxi-mize clinical outcome – meaning to achieve best clinical results, but with significantly less resources bound to the CT system. The ultimate goal: provide medical professionals more time for patients – or patient-centric productivity. The new FAST features, like FAST Plan-ning or FAST Spine, simplify typically time consuming and complex procedures. The scanning process gets more structured and results become more reproducible. Integrating the capabilities of syngo.via,* Siemens’ revolutionary, new imaging software, the complete examination – from scan preparation to data evaluation – is streamlined. This gives medical pro-fessionals significantly more time for what is of utmost importance: the diag-nosis and interaction with their patients, leading ultimately to improved clinical results with less patient burden. This combination of highest image quality at lowest dose and highest patient-centric productivity is the lever to maximizing clinical outcomes. The new SOMATOM Definition AS with FAST CARE will be available from March 2011. * syngo.via can be used as a standalone device or together with a variety of syngo.via based soft-ware options, which are medical devices in their own rights.
- 32. Time is Brain– A Comprehensive Stroke Program at the University of Utah Helps Improve Patients’ Outcome In the event of a stroke, every minute counts. Therefore, recognizing a stroke and treating it quickly and properly takes top priority. With its comprehensive stroke program, the University of Utah is leading the way. By Michaela Spaeth-Dierl, Medical Editor, Spirit Link Medical, Erlangen, Germany and Jakub Mochon, Business Unit CT, Siemens Healthcare, Malvern, PA, USA Stroke is the second leading cause of death worldwide and the most common cause for serious, long-term disability and care dependency. On average, 795,000 persons suffer a new or a recurrent stroke every year and every three minutes someone dies of a stroke. Saving lives and time through close collaboration “The more time that elapses between the event of a stroke and the beginning of therapy, the more brain tissue is destroyed – with corresponding conse-quences for the affected person,” ex plains neuro-interventionalist Edwin A. “Steve” Stevens, professor and chair-man of the department of radiology at the University of Utah Health Sciences Center. Thus, an initially small team consisting of a neuro-interventionalist – Steve Stevens – a neuro-surgeon and a stroke neurologist committed to saving precious time, developed a stroke pro-gram that provides fast and appropriate treatment of the stroke patient. Part of this program is the foundation of a stroke center with a “Brain Attack Team” available 24/7. This multi-disciplinary team now consists of emergency physi-cians, neurologists, neurosurgeons, radiologists, and specially trained nurses and medical staff. This team is notified as soon as a stroke is suspected, often even before the patient reaches the hospital. Staying ahead of the stroke A crucial factor for activating the Brain Attack Team is recognizing a stroke for 32 SOMATOM Sessions · November 2010 · www.siemens.com/healthcare-magazine what it is. Thus, the stroke program aims at educating people who are involved with stroke in order to raise awareness for its symptoms. This includes training programs for physi-cians, rescue workers and nurses, as well as information events for lay people since the latter are often the first to arrive at the scene. Advanced capabilities for an accurate diagnosis and effective therapy A great advantage of the stroke center is that it provides the latest in stroke technology, including CT angiography as well as diffusion and perfusion MR imaging for an accurate diagnosis. Therapies include interventional radi-ology and advanced neurosurgical “CT perfusion plays a tremendous role in assessing what tissue is at risk, which is why performing the study quickly is so important.” Edwin A. “Steve” Stevens, MD, Professor and Chairman of Radiology Business
- 33. Topic SOMATOM Sessions· November 2010 · www.siemens.com/healthcare-magazine 33 techniques such as removing and dis-solving clots or reconstructing ruptured blood vessels. In order to provide the best possible care anywhere, and not just at the University Hospital, the stroke center has established a TeleStroke capability that allows the specialized team to review CT scans performed in remote counties. Fast diagnosis, timely therapy and dose reduction Once the patient has arrived at the hospital and the vital functions have been secured, the next step is to quickly determine whether the brain attack was caused by an ischemic or a hemorrhagic infarction. The time window for initi-ating a thrombolytic therapy after the onset of a stroke is currently three hours. Therefore, the first course of action is a non-contrast CT. “Those initial few minutes make a tre-men dous difference in the outcomes and that’s why we streamline the pro-cedure and the process and why we have real-time interpretation to help us in those decisions,“ says Steve Stevens. The topic of radiation exposure is often mentioned when talking about CT imaging. But in contrast to MR, for example, CT is usually accessible even in small and rural hospitals, and it doesn’t take much time to perform. After a therapy decision has been made, further evaluation by CT angio and perfusion imaging or MR may follow. “So we want to minimize dose, and we also want to make sure that we’re getting the information we need to appropriately take care of our patients,“ summarizes Stevens. Success becomes apparent The success of the stroke program is evidenced by a better outcome for the patients. “Our patients are now arriving much earlier than when we initially started,“ says Steve Stevens. It’s success is reflected in the higher level of education for residents and fellows as well as in additional members of the team who come from other parts of the country to participate in this program. The University of Utah stroke unit is equipped with latest CT scanner technology using a SOMATOM Definition AS+ and the Adaptive 4D spiral technology in order to provide whole brain perfusion in stroke patients. Having a brain attack protocol in place, In-house stroke neurologists, residents, or fellows from the department of Neurology quickly assess the patient and immediately proceed with a CT study to determine the nature of the stroke: ischemic or hemorrhagic.
- 34. syngo.via: Ready forPrime Time in Clinical Practice syngo.via,* the revolutionary new medical imaging software, has arrived in France. The Centre d’Imagerie Médicale de l’Ouest Parisien (CIMOP) is discovering the benefi ts of this sophisticated yet easily accessible visual-ization tool, for both routine as well as advanced reading. We met with Dr. Yves Martin-Bouyer, radiologist at CIMOP. By Christian Rayr It’s not a long way from “Val d’Or” to “Bizet” (see our insert), but for the five radiologists at the Centre d’Imagerie Médicale de l’Ouest Parisien (CIMOP), the West Paris medical imaging centre, and the doctors who work there, the journey hasn’t been necessary for a long time. CIMOP has set up a computer and telephone link to unify patient care between its two sites in Saint-Cloud and Paris. In 1998, this centre, which receives 80,000 patients a year and has the newest image acquisition methods in every field, equipped itself with a Picture Archiving and Communication System (PACS) and a Radiology Information Sys-tem (RIS) that archives all patient cases. Radiologist Dr. Martin-Bouyer explains: “Due to the portability of images and the fact that they can be read on a console, 34 SOMATOM Sessions · November 2010 · www.siemens.com/healthcare-magazine are processed. syngo.via* does the reconstruction according to the exam programmed and the pathology looked for, automatically and without manual intervention. “If I have axial images with a view of the bones,” explains Dr. Mar-tin- Bouyer, “syngo.via* automatically removes the elements not useful for diagnosis and only displays the images I’m interested in according to the appro-priate section. I can see the coronary arteries directly in 3D, as with an angio-gram. I simply click to do a detailed anal-ysis of the vessels, and their trajectory is displayed. I can revolve around a vessel with a 360 degree view, measure a nar-rowing – syngo.via* instantly calculates the percentage – and so on.“ “Here’s another example in oncology,” Dr. Martin-Bouyer continues, “the acqui-sition is done with the ‘cancer’ applica-tion, which prompts syngo.via* to do all the corresponding post-processing. Hepatic metastases are detected. Now, syngo.via* automatically measures the exact volume of each lesion. The data is then made available to the practitioner for reading: if he confirms this data, it is stored in the memory. During the next exam, this data is displayed on the screen and the therapeutic results and/ or development of the disease can be monitored.” we can now make use of the best skills within a team and the geographical loca-tion of the practitioner or tech ni c ian is no longer an issue.” The new syngo.via* software has played a part in this set-up in recent months. It is a considerable “plus” due to its remarkably quick and advanced innovative capacities for image processing and preparation, which are revolutionizing the diagnostic approach. No manual intervention A patient comes to CIMOP for a vascular scan. Once the image acquisition has been done, it is transferred to the PACS where Dr. Martin-Bouyer could do a simple reconstruction in manual mode. But with syngo.via*, he can use the case preparation function instead. A vascular application is selected and the images “Due to the portability of images and the fact that they can be read on a console, we can now make use of the best skills within a team and the geographical location of the practitioner or technician is no longer an issue.” Dr. Yves Martin-Bouyer, radiologist at CIMOP Business
- 35. syngo.via,* which canconnect to a standard PC, can be integrated into all imaging machines and all PACS. SOMATOM Sessions · November 2010 · www.siemens.com/healthcare-magazine 35 Reconstruction time halved The images of various exams, such as whole body MRI scans (where the series of images are automatically organized by stages and sorted into successive sections), and echograms etc. become accessible and comparable with a few clicks. Dr. Martin-Bouyer sums up: “In oncology, the detection and monitoring of changes in lesions and the quality and reliability of reporting are significantly improved now. In vascular, cardiac or peripheral diseases, it is much quicker and easier to analyze lesions. The recon-struction time has been halved for the technician and a coronary scan that took 20 to 25 minutes now takes 10 minutes. When the technician sends me the exam, Christian Rayr, an independent journalist specialized in health and medicine, lives and works in Paris. He contributes to a number of professional medical journals and various health columns in the general press. The Centre d’Imagerie Médicale de l’Ouest Parisien (CIMOP) is a professional health facility dedicated to imaging. ISO 9001/ V2000 certified for all of its activities, it is based in two medi-cal/ surgery clinics (the Clinique Chirurgicale du Val d’Or in Saint- Cloud and the Clinique Bizet in Paris’ 16th district) and offers a whole range of medical examinations: X-rays, echograms, mammograms, osteodensitometry, scans, magnetic resonance imaging (MRI), scintigraphy, cardiovascular and interventional radiology and positron emission tomography (PET). The main specialties concerned are cardiovascular medicine, oncology and neurology. Patient care is computerized from the appointment stage. The time spent in the clinic is half an hour if the patient doesn’t wait for the results, an hour if he or she discusses the results with the doctor who has analyzed them, an hour and a half if he or she waits for the report and copies. Certain exams, vascular exams in particular, take extra time and are available as soon as possible on an approved website. it is ready for reading.” In Val d’Or, the technicians confirm the time saved. For a lower limb exam, it used to take them 10 minutes to process the image; they now need 3 minutes. Easier and quicker to use and more reli-able, syngo.via,* which you can connect to a standard PC, can be integrated into all imaging machines and all PACS. “We can expect that such a diagnostic tool will gradually become a necessity,” predicts Dr. Martin-Bouyer. In autumn 2010, CIMOP will be setting up a dedi-cated unit for interpretation and post-processing, where the best skills and best equipment will be on hand. The Centre d’imagerie Médicale de l’Ouest Pariseien (CIMOP) is based in two medical/surgery clinics (the Clinique Chirurgicale du Val d’Or in Saint-Cloud and the Clinique Bizet in Paris’ 16th district) CIMOP – From Saint-Cloud to Paris Business * syngo.via can be used as a standalone device or together with a variety of syngo.via based software options, which are medical devices in their own rights.
- 36. SOMATOM Spirit: AChoice That Paid Off UMDI Medicina Diagnóstica, in Mogi das Cruzes, Brazil, was the fi rst purchaser of a SOMATOM Spirit in Latin America, a choice that it now recommends to other healthcare centers in the region. By Reinaldo José Lopes SOMATOM Spirit in daily routine; in a typical day about 50 exams can be done, although this number can be as high as 70. 36 SOMATOM Sessions · November 2010 · www.siemens.com/healthcare-magazine Almost as soon as the SOMATOM Spirit was available in the market, Nitamar Abdala, MD, and his colleagues at UMDI Medicina Diagnóstica in Mogi das Cru-zes, a major diagnostic clinic in the Greater São Paulo area, decided to pur-chase the new system. In fact, they were the first in Latin America to do so, a choice that they have never regretted. “The Spirit’s capabilities sounded inter-esting from the start,” says Abdala. “We had already had excellent previous expe-riences with devices produced by Sie-mens. The cost was pretty reasonable, even low, one could say, if you take into account the standard in the market. And both speed and spatiotemporal resolution were very good.” UMDI is now building its first hospital, with the intention of keeping its main focus on diagnosis while also targeting some treatments. According to Abdala, the SOMATOM Spirit was instrumental in helping the clinic to take this next step. “I have already recommended the Spirit to five or six small hospitals with which we have been in touch,” he says. “It is ideally adapted to clinics that are start-ing up. If you’re not sure about how big your demand for exams is going to be, it is a great machine for routine work. You can do nearly anything you need to do with it, leaving just the more compli-cated imaging – involving coronary arteries, for example, where you need to image a big area in nearly real time – to more powerful machines.” Business
- 37. Topic 1A 1B 1C 1D 1 A, B: Nitamar Abdala, MD, is convinced that SOMATOM Spirit fulfills the expectations of small hospitals and furthermore offers a wide range of capabilities. C: Perfusion: Hypoperfused area right frontal in this axial slice. D: Dental: Mandibula and molars in volume rendered technique until the time you exit it, you need only minutes for each patient.” Technician Marcelo Francisco Cardoso agrees: “In a very short time, the patient can have the procedure and leave the clinic with his or her exam in hand. There’s no need for the patient to come back to pick up the results later.” In a typical day, says Abdala, about 50 exams can be done, although this num-ber can be as high as 70. “With the demand for exams that we have, the equipment has paid for itself in two to three years,” he explains. Abdala reports that the increased speed in workflow was the main factor behind the quick return on the investment that UMDI reaped from the SOMATOM Spirit. He also notes that the useful life of Spir-it’s components is quite long when com-pared to other machines, which has also helped the clinic to save money in the long term. “That was another good sur-prise,” he concludes. it does is to give you a very good sense of the width of the bone, so that you can say, with a great degree of confi-dence, whether there’s enough space for an implant there, and what is the best way to place it while taking into account the width of the bone.” (Fig. 1D) Quick return on investment SOMATOM Spirit’s capabilities of volume rendering are also very useful for many kinds of cerebral vascular diagnosis, says Abdala, especially when it comes to imaging the Circle of Willis, a well-known hotspot for aneurysms. When a patient is being prepared for angiography, Spir-it’s CARE Bolus is a valuable “pre-tool,” as he puts it. “It helps you to time, quite precisely, the injection of the contrast with the imaging of brain arteries, for example.” All of Spirit’s features have made work-flow at UMDI twice to three times as fast, according to Abdala. “The machine itself is quite easy to work with, and the software is very user-friendly,” he says. “From the time you enter the room SOMATOM Sessions · November 2010 · www.siemens.com/healthcare-magazine 37 Integrated tools add versatility With the SOMATOM Spirit, the 25 physi-cians at UMDI in Mogi das Cruzes man-age to cover 95 percent of the exams that their patients require. “The remain-ing 5 percent we basically choose not to do ourselves, and we forward those patients to other clinics,” says Abdala. He estimates that, among the exams that are done with the Spirit, around 20 percent involve imaging of the abdomen; the other major applications involve the thorax (15 percent), brain (20 percent) and head and neck (10 percent). For all those kinds of cases, he says, the SOMATOM Spirit was a step forward for UMDI. “Before Spirit, you didn’t have tools like perfusion analysis for tomography, for example. It’s the kind of tool that nor-mally is only available for high-perfor-mance equipment, but we can do these beautifully with Spirit.” Abdala notes that the perfusion tools in Spirit are especially useful when looking into a cerebral vascular incident, like isch-emia involving the occlusion of the carotid artery. “Of course, in those kinds of cases you need to know where to look for the problem. You need to have someone with clinical expertise, someone who is able to interpret the clinical signs of the stroke. But once you know more or less where to look, the perfusion tool gives you a very good picture of the lesion that’s causing the problem.” (Fig. 1C) He also says that the Dental Scan tool has been very useful. It has helped to bring to the clinic patients that normally wouldn’t be there – those who need to be checked for the feasibility of a dental implant. “It’s a simple tool, but very effective,” says Abdala. “Basically, what Reinaldo José Lopes is the science editor at Folha de S.Paulo, Brazil’s largest daily newspaper.
- 38. Clinical Results Cardio-Vascular Case 1 SOMATOM Defi nition Flash: Ruling out Coronary Artery Disease with 0.69 mSv By Ralf W. Bauer, MD, J. Matthias Kerl, MD and Thomas J. Vogl, MD Goethe University Clinic, Department of Diagnostic and Interventional Radiology, Frankfurt, Germany HISTORY A 68-year-old patient with atypical chest pain and known, year-long arterial hypertension presented at the radiology department in order to rule out coronary artery disease. Ultrasound showed con-centric left ventricular (LV) hypertrophy and aortic valve stenosis, grade 1. The resting heart rate was 50 bpm and no beta-blockers were injected. DIAGNOSIS Coronary CT angiography using the pro-spectively ECG-gated Flash Spiral was performed utilizing only 0.69 mSv radia-tion dose. Mild concentric LV hypertro-phy and minor calcifications of the aortic valve were found. There was no sign of macroangiopathic arteriosclerotic changes in the main coronary arteries and their major branches. Coronary artery disease could be ruled out in this patient. COMMENTS In only 0.29 seconds scan time without the use of beta-blockers, Coronary CT angiography using 100 kV tube voltage and the Flash Spiral acquisition mode allowed ruling out coronary artery dis-ease 38 SOMATOM Sessions · November 2010 · www.siemens.com/healthcare-magazine 1 Volume rendered display of the major coronary arteries was underlined with multi-planar recon-struction (MPR). 2 Caudo-cranial view of the distal part of the right cor-onary artery (RCA) and patent ductus arteriosus (PDA). 1 2 in this normal-sized adult patient (185 cm / 86 kg) with a DLP of 49. The smallest myocardial branches of the right coronary artery (RCA), left anterior descending artery (LAD) and left circum-flex coronary artery (LCX) could be visu-alized, underlining best image quality at lowest dose values.
- 39. Cardio-Vascular Clinical Results 3 Curved planar reformatted (CPR) display of the RCA. 4 90 degree angulated view of the RCA (compared with Fig.3). 5 Curved planar reformatted (CPR) display of the left anterior descend-ing SOMATOM Sessions · November 2010 · www.siemens.com/healthcare-magazine 39 3 4 EXAMINATION PROTOCOL Scanner SOMATOM Definition Flash Scan mode Flash Spiral Rotation time 0.28 s Scan area Heart Pitch 3.4 Scan length 135 mm Slice collimation 128 x 0.6 mm Scan direction Cranio-caudal Slice width 0.75 mm Scan time 0.29 s Reconstruction increment 0.4 mm Heart rate 50 bpm Reconstruction kernel B26f Tube voltage 100 kV / 100 kV Contrast Tube current 370 mAs/rot. Volume 70 ml Dose modulation CARE Dose4D Flow rate 5 ml/s CTDIvol 2.59 mGy Start delay Test bolus DLP 49 mGy cm Postprocessing syngo InSpace4D Effective Dose 0.69 mSv artery LAD. 6 CPR display of the entire course of the LAD. 5 6
- 40. Case 2 SOMATOMDefi nition Flash: Low-Dose Abdomen Pediatric Scan: Follow-Up Study of Fibromuscular Dysplasia By Pia Säfström, MD, Nils Dahlström, MD and Petter Quick Department of Radiology and Center for Medical Image Science and Visualization (CMIV), Linköping University Hospital, Linköping, Sweden 1 40 SOMATOM Sessions · November 2010 · www.siemens.com/healthcare-magazine 1 Fused volume-rendered view showed variant vascular anat-omy consisting of the common hepatic artery (arrow). Clinical Results Cardio-Vascular
- 41. DIAGNOSIS A fibromusculardysplasia (FMD) of the renal arteries caused the hypertension. This led to the suspicion of FMD in visceral arteries. CT imaging showed variant vascular anatomy consisting of the common hepatic artery arising from the superior mesenteric artery (Fig. 1 and Fig. 3). SOMATOM Sessions · November 2010 · www.siemens.com/healthcare-magazine 41 HISTORY A seven-year-old boy who had been diagnosed two years prior with fibro-muscular dysplasia (FMD) of a right renal segmental artery causing severe hypertension, presented at our depart-ment for a follow-up study. After suc-cessful balloon angioplasty, the blood pressure normalized. On a follow-up CT angiography, small caliber changes in the superior mesenteric and gastro-duo-denal arteries were suspected. Later follow-up CTA showed no progression of these findings but new, minute changes in the renal arteries were noted. Further monitoring with CTA is warranted. 2 A coronal curved inverted maximum intensity projection (MIP) view discovered both renal arteries 3 A curved inverted maximum intensity projection (MIP) allowed this view on the hepatic artery (arrow). 4 Coronal inverted MIP showed superior mesenteric artery EXAMINATION PROTOCOL Scanner SOMATOM Definition Flash Scan mode Flash Spiral Rotation time 0.28 s Scan area Abdomen Pitch 3 Scan length 240 mm Slice collimation 128 x 0.6 mm Scan direction Cranio-caudal Slice width 0.75 mm Scan time 0.6 s Reconstruction increment 0.6 mm Tube voltage 80 kV Reconstruction kernel B31f Tube current 88 mAs Contrast Dose modulation CARE Dose4D Volume 20 ml, 320 mg/ml CTDIvol 1.4 mGy Flow rate 2 ml/s DLP 44 mGy cm Start delay CARE Bolus, trigger 130 HU Eff. Dose 0.88 mSv Postprocessing syngo 3D Basic 2 3 4 Cardio-Vascular Clinical Results COMMENTS CTA provides accurate visualization of the visceral and renal arteries. Low-dose CT technique is advocated in pediatric patients, especially when repeated follow-up examinations are expected. In this case the total effec-tive dose was 0.88 mSv using the published conversion factor from DLP to effective dose of 0.02 mSv / (mGy cm) for a five-year-old abdomen exam.
- 42. Clinical Results Cardio-Vascular Case 3 CT Dynamic Myocardial Stress Perfusion Imaging – Correlation with SPECT Kheng-Thye Ho, FACC,* Kia-Chong Chua, MSC,* Ernst Klotz,** and Christoph Panknin,** *Department of Cardiology, Tan Tock Seng Hospital, Singapore, Republic of Singapore **Business Unit CT, Siemens Healthcare, Forchheim, Germany HISTORY A 61-year-old male with cardiac risk fac-tors of hypertension and hyerlipidemia presented with symptoms of atypical chest pain. Resting ECG was unremark-able. Dipyridamole-stress nuclear myocar-dial perfusion imaging (NMPI) had dem-onstrated a very large, reversible defect involving the apex, anterior wall and sep-tum. The total defect size was quantified 1 42 SOMATOM Sessions · November 2010 · www.siemens.com/healthcare-magazine 1 CT dynamic stress MPI with SPECT correlation in the mid-ventricular short axis (1A) and the horizontal long axis view (1B). Stress are images in the upper quadrants, rest images below; CT perfusion to the left of the corre-sponding SPECT. 2 Invasive angiography findings: Total occlusion of the proximal LAD and a 90% lesion in OM3 (2A, arrow), and 75% lesion in the RPDA branch of the otherwise normal RCA (2B, arrowhead). as 34% of the left ventricle. Left ventricu-lar ejection fraction was estimated as 65% in the post-stress images by gating. Post-stress dilatation was noted in the scan, which is an adverse prognostic sign in the presence of coronary artery dis-ease. Invasive coronary angiography demonstrated total occlusion of the prox-imal LAD, with collaterals arising from both the LCx and RCA. There was also a 90% lesion in the third obtuse marginal branch (OM3) and a 75% lesion in the right posterior descending artery (RPDA) branch of the right coronary artery (RCA). CT myocardial perfusion imaging (MPI) was performed prior to CABG.[1] The patient underwent successful coro-nary bypass surgery, with a left internal 1A 1B 2A 2B
- 43. Topic 3A 3B3C vascular resistance in the LCx and RCA bed drops, and blood preferentially flows into these territories, even from the LAD territory, resulting in reduction of MBF in septum and anterior wall below that in the rest scan (0.57 cc/cc/min compared to 0.82 cc/cc/min). The LAD bed is already maximally vasodilated due to the pre-exist-ing complete occlusion of LAD, and the vascular resistance is unable to be reduced further. Hence the steal phenomenon. The absence of a perfusion defect in the LCx territory in both CT MPI and NMPI suggests that flow reserve is maintained there despite the presence of stenosis in the LCx. SOMATOM Sessions · November 2010 · www.siemens.com/healthcare-magazine 43 3D 3E mammary artery (LIMA) to the mid-left artery descending (LAD), saphenous vein graft (SVG) to RPDA and OM. DIAGNOSIS CT dynamic stress MPI demonstrated a reversible defect in the apex, anterior wall, and septum as seen in NMPI. The myocardial blood flow (MBF) of the anterior wall and septum during appli-cation of dipyridamole-stress was 0.57 cc/cc/min (blue), whereas the normal tissue, i.e., the inferior wall and lateral wall, had an MBF of 1.09 cc/cc/min (red). In the rest-scan, the defect resolved and MBF was similar to that of the normal myocardium at rest, 0.82 cc/ cc/min and 0.81 cc/cc/min (yellow-green). The mean MBF of the normal myocardium was 0.90 cc/cc/min and 0.81 cc/cc/min at stress and rest, respec-tively. COMMENTS Another relevant finding was the reduc-tion of MBF in the defect area at stress even below its MBF at rest. This is evi-dence of a horizontal myocardial steal occurring during vasodilator stress. These findings are compatible with the angio-graphic findings of severe, complete occlusion of the proximal LAD, and the presence of collaterals from the left cir-cumflex coronary artery (LCx) and right coronary artery (RCA). In the normal rest-ing situation, collaterals form LCx and RCA supply the myocardium in the occluded LAD territory. During vasodilator stress, 3 Good correlation of CT MPI and SPECT for apex (3A), mid-ventricular (3B), and base short axis views (3C) as well as vertical (3D) and horizontal (3E) long axis views. Arrangement of Stress/Rest/CT/SPECT as in image 1. 1 Stress and Rest Dynamic Myocardial Perfusion Imag-ing by Evaluation of Complete Time-Attenuation Curves With Dual-Source CT. JACC Imaging 2010; 3: 811–20. KT Ho, KC Chua, E Klotz, C Panknin. EXAMINATION PROTOCOL Scanner SOMATOM Definition Flash Scan length 73 mm Slice collimation 128 x 0.6 mm Scan time 30 s Reconstruction increment 2 mm Heart rate 82 bpm for stress image, 73 bpm for rest image Reconstruction kernel B25 Tube voltage 100 kV Contrast Ultravist® 370 mg iodine / ml Tube current 300 mAs/rot Volume 60 ml Flow rate 6 ml/s CTDIvol 653 mGy (stress), 649 mGy (rest) Start delay Scan start 4 s before arrival of contrast in left ventricle Rotation time 285 ms Postprocessing syngo VPCT Body Myocardium
- 44. Case 4 SOMATOMDefi nition Flash Motion-free Thoracic Infant Scan: Follow-Up Study After Chemotherapy By Susann Skoog, MD, Nils Dahlström MD, and Petter Quick Department of Radiology and Center for Medical Image Science and Visualization (CMIV), Linköping University Hospital, Linköping, Sweden HISTORY A three-year-old boy with small (7-8 mm diameter) lung metastases from a germ-cell tumor, successfully treated with chemotherapy, was referred for follow-up CT of the thorax. In a previously acquired CT-examination without sedation, utilizing DLP 51.95 mGycm, 3.28 mGy CTDi vol / scan length 140 mm, the patient had been coope rative. In the present Flash scan, no remaining metastases were identified and the serum tumor marker Alpha Fetoprotein (AFP) levels were normal. EXAMINATION PROTOCOL DIAGNOSIS The ultra-fast thoracic scan mode, using pitch value of 3, did not reveal any met-astatic lesions or other pathological find-ings in the thorax. Both lungs were well perfused and there was no sign of any enlarged lymph nodes. The size of the thymus was increased moderately. Inverted maximum intensity projection (MIP) showed a regular bronchial tree. COMMENTS Continuous follow-up CT examinations are necessary to monitor the treatment effect and determine the complete Scanner SOMATOM Definition Flash Scan mode Flash Spiral Thorax Eff. Dose 0.54 mSv Scan area Thorax CTA Pitch 3 Scan length 172 mm Slice collimation 128 x 0.6 mm Scan direction Cranio-caudal Slice width 0.75 mm Scan time 0.42 s Reconstruction increment 0.6 mm Tube voltage 120 kV Reconstruction kernel B31f Tube current 20 mAs Contrast Dose modulation CARE Dose4D Volume 30 ml Ultravist® 370 mg / ml CTDIvol 1.23 mGy Flow rate 1 ml/s Rotation time 0.28 s Start delay 30 s DLP 30 mGy cm Postprocessing syngo InSpace4D 44 SOMATOM Sessions · November 2010 · www.siemens.com/healthcare-magazine patient response. Using the high-pitch spiral acquisition of the SOMATOM Definition Flash CT, patients can always be examined with greatly reduced radia-tion dose in comparison to standard CT protocols. In this case only 0.54 mSv* were necessary to be applied. The fast scan mode which acquired the patients’ thorax in only 0.42 seconds avoided the need to sedate this pediatric patient. The resulting images were obtained motion free and delivered excel-lent and valuable data for a safe diagno-sis without the need of a second scan. Clinical Results Oncology * Effective Dose was calculated using the published conversion factor for a pediatric (5 year old) chest of 0.036 mSv (mGy cm)-1 [1]. To take into account that Siemens calculates the CTDi in a 32 cm CTDi phantom, an additional correction factor of 2 had to be applied. [1] McCollough CH et al Strategies for Reducing Radiation Dose in CT.
- 45. SOMATOM Sessions ·November 2010 · www.siemens.com/healthcare-magazine 45 5 Coronal view from previous CT Scanner (51.95 DLP, arrows) showed motion caused by breathing. 1 5 6 Sagittal view from previous CT Scanner (arrows) of breathing patient made diagnosis more difficult. 6 3 Inverted Maximum Intensity Projection (MIP) shows a regular bronchial tree. 3 4 Bilateral well-perfused lung in this coronal view could be recognized. 4 1 CT imaging resulted in a fused volume rendered view of the entire chest. 1 2 A sagittal view highlights the absence of motion, especially visible in the patients’ diaphragm (arrow). 2
- 46. Clinical Results Oncology Case 5 SOMATOM Defi nition Flash: Dual Energy Carotid Angiography for Rapid Visualization of Paraganglioma By João Carlos Costa, MD;* J. Oliveira, MD;* J. Dinis, MD;* R. Duarte, MD;* O. Borlido, RT;* M. Gonçalves, RT;* D. Martins, RT;* S. Silva, RT;* D. Teixeira, RT,* A. Chaves,** and Andreas Blaha** * Radiology Department, Hospital Particular de Viana do Castelo, Viana do Castelo, Portugal ** Business Unit CT, Siemens Healthcare, Forchheim, Germany HISTORY A 30-year-old female patient with a one-year history of progressive growth of a right cervical mass was referred to the CT department. There were no associated local symptoms. The patient did not com-plain of pain but reported physical weak-ness. An echo-doppler study revealed a well-defined solid mass between the internal and external right carotid arter-ies with intense arterial irrigation being suggestive of a paraganglioma. DIAGNOSIS A Dual Energy CT angiography examina-tion confirmed a solid mass with the size of 2.5 cm in diameter, located in the right carotid bulb which could lead to carotid paraganglioma. The arterial enhance-ment of the carotid arteries did not show any signs of stenoses or occlusions. There is no vascular abnormity present in the Circle of Willis. Due to exact contrast timing, venous contamination could be avoided. 46 SOMATOM Sessions · November 2010 · www.siemens.com/healthcare-magazine A typical sharp delineation of the lesion in the right carotid artery confirmed the suspicion of paraganglioma. The patient was referred to surgery where the initial diagnosis could be confirmed. A complete isolation and resection of the paraganglioma could be achieved. Convalescence of the patient was short and no complications arose. 1 Dual Energy VRT of the right carotid artery shows a cervical mass. 2 Dual Energy VRT view of right carotid artery, focusing on carotid bifurcation (arrow). 1 2
- 47. diagnosis and theadditional benefit from second contrast for tissue charac-terization or virtual non-contrast (VNC) that eliminates the need for an addi-tional non-contrast scan. 3 Axial MPR high-lights vascular sta-tus of the paragan-glioma (arrow). 4 Coronal MPR of the paraganglioma (arrow). 5 Coronal angio view compares both carotids. 6 Lateral angio view focusing on paraganglioma in carotid bulb (arrow). cervical spine could be immediately hidden and the vascular status was immediately visible. Vascular examinations are acquired in Dual Energy technique allowing fast 3 4 SOMATOM Sessions · November 2010 · www.siemens.com/healthcare-magazine 47 COMMENTS The SOMATOM Definition Flash allows the acquisition of Dual Energy examina-tion at a low-dose level of 0.84 mSv. Using syngo DE Direct Angio, the EXAMINATION PROTOCOL Scanner SOMATOM Definition Flash Scan mode Dual Energy Slice width 1 mm Scan area Carotid CTA Reconstruction increment 0.5 mm Scan length 185 mm Spatial Resolution 0.33 mm Scan direction Cranio-caudal Reconstruction kernel D26f Scan time 5 s DLP 68 mGy cm Tube voltage 140 kV / 100 kV Effective Dose 0.84 mSv Tube current 139 / 139 eff. mAs Contrast Dose modulation CARE Dose4D Volume 70 ml contrast CTDIvol 3.29 mGy Flow rate 5 ml/s Rotation time 0.28 s Start delay 6 s Slice collimation 64 x 0.6 mm PostProcessing syngo Dual Energy Direct Angio 5 6 Oncology Clinical Results
- 48. Clinical Results Oncology Case 6 Total Occlusion of the Left Superior Pulmonary Vein by a Metastasis Detected with Dual Energy CT By Lucía Flors, MD, Carlos Leiva-Salinas, MD, Klaus D. Hagspiel, MD Department of Radiology, University of Virginia, VA, USA HISTORY A 58-year-old male patient with history of metastatic melanoma (pulmonary, pleu-ral mediastinal and brain metastases), recurrent malignant pleural effusion that required multiple episodes of thoracocen-tesis and recent right thoracoscopic talc pleurodesis (specific form of chemical pleurodesis), was presented with acute onset of shortness of breath and tachy-cardia. He was referred to our depart-ment for CT angiography in order to rule out pulmonary thromboembolism. 1 CTPA coronal sub-volume, Maximum Intensity Projection (MIP) shows right and left hilar, mediastinal as well as right pleural metastases. The left hilar mass encases and occludes the left superior pulmonary vein (arrow). The left upper pulmonary artery remains permeable (arrowhead). 48 SOMATOM Sessions · November 2010 · www.siemens.com/healthcare-magazine DIAGNOSIS The Dual Energy CT images showed mul-tiple bulky mediastinal, bilateral hilar and right pleural metastases. The left mediastinal lesions produced encase-ment and occlusion of the left superior pulmonary vein. The Dual Energy perfused blood volume (PBV) images revealed a severe perfusion defect in the left upper lobe, caused by the complete tumoral occlusion of the left upper pul-monary vein. Smaller caliber of vessels were noted in the low-attenuating por-tion of the under-perfused lung. COMMENTS One of the main pulmonary applications of PBV Dual Energy CT is the assessment of perfusion defects due to pulmonary embolism. However, alterations in pul-monary perfusion are not caused only by disruption of the arterial supply but also by problems with venous drainage. The simultaneous evaluation of the iodine perfusion map and the morpho-logical CT angiographic images allows precise evaluation of the derangements in the pulmonary vascular supply or drainage and their resulting perfusion defects. This information is obtained from one single scan and thus without dose penalty. 1
- 49. 2A 2B 2Axial (Fig. 2A) and coronal (Fig. 2B) images in lung window setting show relative hypodensity of the left upper lobe, a large left pulmo-nary effusion and a right hilar mass with near complete occlusion of the superior vena cava. Smooth septal thickening is also seen in the right upper lobe, most likely due to interstitial edema. Chest drainage tubes are seen in the right arrow pleural space as well as a small amount of pleural air related to the recent pleurodesis. 3A 3B 3C 3 Coronal (Fig. 3A and 3B) and axial (Fig. 3C) Dual Energy Lung PBV images demonstrate near complete loss of perfusion of the left upper lobe caused by metastasis occluding the left superior pulmonary vein. Alteration of the perfusion is also noted within the right upper lobe due to septal thickening. SOMATOM Sessions · November 2010 · www.siemens.com/healthcare-magazine 49 EXAMINATION PROTOCOL Scanner SOMATOM Definition Scan mode Dual Energy Lung Scan area Thorax Slice collimation 0.6 mm Scan length 308 mm Slice width 1.5 mm Scan direction Cranio-caudal Reconstruction increment 1 mm Scan time 10 s Reconstruction kernel B30f Tube voltage A/B 140 kV / 80 kV Contrast Tube current A/B 93 eff. mAs / 382 eff. mAs Volume 100 ml of 350 mg/ml Dose modulation CARE Dose4D Flow rate 4 ml/s CTDIvol 16.90 mGy Start delay 17 s Rotation time 0.5 s Postprocessing syngo DE Lung PBV
- 50. Case 7 SOMATOMSpirit: Follow-Up Examination of Cerebral Meningioma By Wolfgang Gerlach, MD,* Andreas Blaha** *Private Practice, Heidenheim, Germany, **Business Unit CT, Siemens Healthcare, Forchheim, Germany HISTORY This 74-year-old female patient under-went a regular follow up procedure of the known meningioma located in the ventral part of the clivus. To exclude progress of the meningioma a CT-Angiography was ordered. DIAGNOSIS The cerebral CT-Angiography (CTA) was performed with 80 ml of contrast media to achieve a good delineation of the meningioma. A homogeneous opacifica-tion of the lesion needed to be achieved (Mean density could be measured with 110 Hounsfield units, HU). The menin-gioma is situated at the clivus, almost extending to the foramen magnum. The size was measured with 2.9 x 2.5 cm. The sagittal view of the CTA shows the extension towards the spinal cord, but no derogation of the spinal cord could be seen. No abnormity of the cerebral vas-cular system could be detected. COMMENTS The patient requires continuous moni-toring to detect early signs of progression of the lesion. Therefore a low dose pro-tocol was selected 0.5 mSv*. No pro-gression could be observed, so the next monitoring examination is recommended in 12 months. To achieve the pure arterial contrast 1 Cranio-caudal view of the CTA, good opacification of the meningioma (arrow). 1 50 SOMATOM Sessions · November 2010 · www.siemens.com/healthcare-magazine region of the patients meningioma and makes it the preferred visualization method for detecting and monitoring cerebral meningioma. timing an automatic contrast bolus tracking software (CARE Bolus CT) was utilized. CT provides the exact measure-ment and location in the very dense Clinical Results Oncology * Effective Dose was calculated using the pub-lished conversion factor for an adult head of 0.0021mSv (mGy cm)-1 [1]. [1] McCollough CH et al. Strategies for Reduc-ing Radation Does in CT, Radiol. Clin. N. Am. 47: (2009) 27-40.
- 51. 2 View ofthe meningioma showing (arrow) arteria communis posterior exiting. 3 Caudo-cranial view of the meningioma, mean densitiy values of 110 HU. 4 Sagittal view of meningioma, no spinal cord disturbance (arrows). SOMATOM Sessions · November 2010 · www.siemens.com/healthcare-magazine 51 EXAMINATION PROTOCOL Scanner SOMATOM Spirit Scan mode Spiral Pitch 1.5 Scan area Head Slice collimation 1.5 mm Scan length 66 mm Slice width 2 mm Scan direction Caudo-cranial Reconstruction increment 1 mm Scan time 22 s Reconstruction kernel H31s Tube voltage 130 kV Contrast Tube current 165 eff. mAs Volume 80 ml CTDIvol 33 mGy Flow rate 2 ml/s Rotation time 1.5 s Start delay CARE Bolus DLP 239 mGy cm Postprocessing syngo InSpace4D Eff. Dose 0.5 mSv 2 3 4 Oncology Clinical Results
- 52. Case 8 SOMATOMDefi nition Flash: Improving Image Quality of Brain Scans With IRIS, X-CARE and Neuro BestContrast By Dominik Augart, Barbara Wieser and Christoph Becker, MD Department of Radiology, Ludwig-Maximilians-University, Munich, Germany COMMENTS Due to the newest scan and reconstruc-tion technologies, a significantly better image quality resulted making a better delineation of bleeding possible. The differentiation between old and new blood was also substantially improved. A further significant advantage of these new procedures is not only better image quality but also dose reduction. In our EXAMINATION PROTOCOL Scanner SOMATOM Definition Flash SOMATOM Sensation 64 Scan area Head Head Scan length 150 mm 150 mm Scan direction Cranio-caudal Cranio-caudal Scan time 9 s 30 s Tube voltage 120 kV 120 kV Tube current 320 mAs 306 mAs Rotation time 1.0 s 1.0 s Dose modulation CARE Dose 4D, X-CARE CARE Dose4D CTDIvol 42.21 mGy 49.80 mGy DLP 661 mGy cm 761,88 mGy cm Effective Dose 1.4 mSv 1.6 mSv Slice collimation 128 x 0.6 mm 40 x 0.6 mm Slice width 5 mm 5 mm Reconstruction J37s H37 kernel HISTORY A 76-year-old female patient with a chronic dural hematoma following a fall presented at our department. The first scan was performed 24 hours after the fall with a SOMATOM Sensation, 64-slice scanner utilizing CARE Dose4D. To check progress of the wound, a follow-up scan of the skull was requested. An additional exam was taken 7 days later with a SOMATOM Definition Flash utilizing IRIS, X-CARE, and Neuro BestContrast. DIAGNOSIS The first scan revealed a chronic sub-dural hematoma with old as well as fresh blood. There was no indication of intra-cerebral, subarachnoid or intra-ventricular bleeding. Additionally, there was no indication of an ischemic event. A significantly better judgment of the spread and differentiation between old and new blood as well as the chronic subdural hematoma was first possible with the second examination one week later. This clearly showed additional hypodense structure indicating fresh bleeding that could not be detected in the previous examination. 52 SOMATOM Sessions · November 2010 · www.siemens.com/healthcare-magazine follow-up study, we were able to de - termine, in addition to an overall dose reduction, close to 40% less dose applied to the eye lens. This is parti-cularly important in order to minimize the possibility of long-term damage to the eye lens for young patients who must undergo repeated scans. Clinical Results Neurology
- 53. 1A 1B 1Significantly improved image quality to delineate the bleeding (arrow). Chronic dural hematoma (Fig. 1B arrow). 2 Fresh bleeding could be outlined by the hypodense structure (arrow) that couldn’t be clearly seen in the initial examination (Fig. 2B arrow). SOMATOM Sessions · November 2010 · www.siemens.com/healthcare-magazine 53 Flash Flash S64 S64 2A 2B
- 54. Case 9 VolumePerfusion CT Neuro as a Reliable Tool for Analysis of Ischemic Stroke Within Posterior Circulation By Philipp Gölitz, MD Department of Neuroradiology, University of Erlangen-Nuremberg, Erlangen, Germany 54 SOMATOM Sessions · November 2010 · www.siemens.com/healthcare-magazine HISTORY A 90-year old male patient was brought to our hospital with a right-sided hemi-paresis and aphasia existing for two and a half hours. Physical examination showed an NIHSS (National Institute of Health stroke score) of 18. No history of neurological disorders or absolute arrhythmia was known. From the clinical appearance it was suspected that the symptoms could be caused by an infarc-tion within the left middle cerebral artery territory. DIAGNOSIS The neuro-radiologic examination started with a cranial, non-enhanced CT (NECT) scan for ruling out intracranial hemorrhage or tumor. A short segment of the proximal part of the left posterior cerebral artery (P1-segment of PCA) was found to be hyperdense as a sign of thrombembolic occlusion. The grey and white matter distinction was not altered. Next a volume perfusion CT (VPCT) was performed. It revealed a delayed time to peak (TTP) of the whole left PCA-terri-tory including the thalamus and the left cerebral peduncle. Also the mean transit time (MTT) was prolongated. On the other hand there was no definable reduction of the cerebral blood volume (CBV) and the cerebral blood flow within the PCA-territory. Additionally, measure- 1 Delayed Time to peak (TTP) and prolonged mean transit time (MTT) show a delay of blood flow in the whole left PCA-territory including the thalamus and the left cerebral peduncle whereas cerebral blood volume (CBV) and cerebral blood flow (CBF) were unchanged. 1 Clinical Results Neurology
- 55. Neurology Clinical Results 3 Fusion of CTA and TTP delay indicate the occlusion (arrow) and the corresponding perfusion delay in the PCA-territory (arrowhead). 2 3 via the (also in the CTA visible) 2 CT-angiography (CTA) detected the P1-segment occlusion (arrow) on the left side. left posterior communicating branch from the anterior circulation. The para-meter constellation of the VPCT indi-cated a large penumbra volume and so it was decided to start an intravenous lysis therapy. The therapy was successful and the patient recovered remarkably. The follow-up NECT on next day showed no delineation of any infarction. COMMENTS This case illustrates, that VPCT allows a reliable analysis concerning ischemic stroke changes also within the posterior circulation territory including thalamus and midbrain. Moreover, the VPCT can be used as a quick, feasible tool for the assessment of the tissue at risk and thereby the patient management could be influenced. SOMATOM Sessions · November 2010 · www.siemens.com/healthcare-magazine 55 ment of the permeability was per-formed, which was slightly increased only in a few cortical parts. This could be interpreted as a predictor of a reduced risk of developing a hemorrhagic stroke transformation. In correlation to the early stroke sign of the NECT the CT-angiography (CTA) detected the P1-segement occlusion on the left side. The P2- and P3-segment of the PCA were regularly contrasted, pre-sumably EXAMINATION PROTOCOL Scanner SOMATOM Definition AS+ Scan mode Adaptive 4D Spiral Slice collimation 0.6 mm Scan area Head Slice width 3 mm Scan length 96 mm Reconstruction increment 1 mm Scan direction Caudo-cranial and cranio-caudal Reconstruction kernel H20f Scan time 46 s Contrast Ultravist® 370 mg/ml Tube voltage 80 kV Volume 30 ml Tube current 200 mAs Flow rate 5 ml/s CTDIvol 218 mGy Postprocessing syngo Volume Perfusion CT Neuro Rotation time 0.3 s
- 56. Case 10 DualSource, Dual Energy CT: Improvement of Lung Perfusion Within 5 Hours in a Patient With Acute Pulmonary Embolism By Tetsuro Nakazawa, MD; Masahiro Higashi, MD, PhD; Hiroaki Naito, MD, PhD Department of Radiology, National Cardiovascular Center, Osaka, Japan HISTORY A 70-year-old woman complained about dyspnea and chest discomfort on exertion. The symptoms gradually worsened and she was referred to our center with suspicion of acute coronary syndrome. An ECG was almost normal, but laboratory test results showed mild, increased fibrinogen, and Ultrasound Cardiography (UCG) showed right ventricle dilatation and tricuspid regurgitation. From these results, we suspected pulmonary thromboembolism and ordered a Dual Energy CT scan. DIAGNOSIS The first Dual Source CT examination in the Dual Energy mode was taken at 11:30. The mixed images revealed thrombi in both pulmonary artery trunks reaching into the branches and the patient was diagnosed with pulmonary embolism. Dual Energy lung perfused blood volume (PBV) images showed perfusion defects in the right lung and the left lingular and lower lobe corre-sponding to the location of the throm-bus. 11:30 16:30 1 CT at 11:30 shows thrombus located in both pulmonary arteries (Fig. 1A and 1B).The Lung PBV Dual Energy data revealed a significant reduction of pulmonary perfusion (Fig. 1C and 1D). 56 SOMATOM Sessions · November 2010 · www.siemens.com/healthcare-magazine Heparin therapy was started. Throm-bolytic therapy was planned, and then an Inferior Vena Cava (IVC) filter was placed. The patient felt instant relief from dyspnea and therefore a follow-up Dual Energy CT scan was performed at 16:30. The mixed CT images revealed that the thrombus was unchanged com-pared to five hours earlier. Yet, the Dual Energy lung PBV images showed that the patient’s lung perfusion had improved. 2 After initiating heparin therapy no reduction of thrombus could be observed (Fig. 2A and 2B), … 1A 1B 1C 1D 2A 2C 11:30 11:30 11:30 16:30 Clinical Results Acute Care
- 57. Now, only asmall mismatch between the images was seen at the periphery of the middle lobe of the right lung and the lin-gular segment of the left lung. COMMENTS In the past, scintigraphy was used for PE diagnosis. In recent years however MDCT has replaced scintigraphy for PE diagno-sis. The diagnosis can be done by con-firming clots in vessels with CT. In the case of this patient, PE could be diag-nosed on single Energy CT, but the rea-son Acute Care Clinical Results for the improvement of clinical symp-toms could not be confirmed. Only with PBV images acquired by Dual Energy CT could we presume that pulmonary perfu-sion improvement was the cause for the relief of the symptoms. Perhaps this was the result of an increased blood flow around the thrombus, which was too small to be seen from the state of the thrombus itself. Only functional images (meaning perfusion images) could reveal it. We were able to see this small change with only one Dual Energy CT scan. Dual Energy Lung PBV was extremely helpful in this case. 3A 3B SOMATOM Sessions · November 2010 · www.siemens.com/healthcare-magazine 57 Considering the patient’s age and physi-cal condition, a wait-and-see approach was decided and anti-coagulation with heparin and warfarin were continued. The patient’s symptoms gradually improved. One week later we confirmed on Dual Energy Lung PBV images that perfusion had improved in large parts, but slightly decreased perfusion was still seen in the mid-right lobe and upper left and left lingular segments. The thrombus had disappeared on the mixed CT images. Two weeks later, the patient underwent perfusion and ventilation scintigraphy. EXAMINATION PROTOCOL Scanner SOMATOM Definition Scan mode Dual Energy Lung PBV Pitch 0.8 Scan area Thorax Slice collimation 0.6 mm Scan length 290 mm Slice width 1 mm Scan direction Cranio-caudal Reconstruction increment 1 mm Scan time 6.9 s Reconstruction kernel D30f Tube voltage A/B 80 kV / 140 kV Contrast Tube current A/B 45 mAs / 225mAs Volume 60 ml Dose modulation CARE Dose4D Flow rate 2 ml/s Rotation time 0.33 s Postprocessing Dual Energy Lung PBV 3C 3D … but a considerable improvement of lung perfusion (Fig. 2C and 2D). 3 CT Dual Energy Lung PBV one week later showed almost complete perfusion recovery (Fig. 3A and 3B). 2 weeks later perfusion and ventilation scintigraphy unveiled only a small remaining defect (Fig. 3C and 3D). 2B 2D 16:30 1 week later 1 week later 16:30 2 weeks later 2 weeks later
- 58. Case 11 Differentiationof Pulmonary Emboli and Their Effect on Lung Perfusion Determined With a Low-Dose Dual Energy Scan By Lucía Flors, MD, Carlos Leiva-Salinas, MD, Klaus D. Hagspiel, MD Department of Radiology, University of Virginia, VA, USA HISTORY A 48-year-old male patient, status post right lung transplant with history of coal worker’s pneumoconiosis, emphysema and left upper lobe lobectomy, pre-sented with acute onset of shortness of breath. He was referred to our depart-ment for CT angiography in order to rule out pulmonary thromboembolism. DIAGNOSIS On the Dual Energy CT images, an acute pulmonary embolus was noted within the right lower lobe pulmonary artery, involving the segmental and sub-seg-mental arteries. The Dual Energy Perfu-sion Blood Volume (PBV) images revealed perfusion defects in lung areas matching the location of the thrombi. Scattered perfusion defects were also seen throughout the left lung paren-chyma due to decreased pulmonary den-sity EXAMINATION PROTOCOL in areas of severe emphysema and bullous disease as revealed in the lung window setting. A hemodynamically, probably not significant, narrowing of the pulmonary arterial anastomosis rela-tive to the donor main pulmonary artery was also noted. The venous and bron-chial anastomoses were normal. COMMENTS One of the key advantages of Dual Energy CT PBV is the ability to differenti-ate between occlusive and non-occlusive pulmonary emboli. Functional informa-tion is added to the otherwise purely morphological assessment provided by standard CT Pulmonary Angiography and thus makes it possible to custom tai-lor therapy in certain high risk patients. Because the Dual Energy CT PBV algo-rithm is optimized for the detection of Scanner SOMATOM Definition Scan mode DE Lung Pitch 0.8 Scan area Thorax Slice collimation 0.6 mm Scan length 328.5 mm Slice width 1.5 mm Scan direction Cranio-caudal Reconstruction increment 1 mm Scan time 11 s Reconstruction kernel B30f Tube voltage A/B 140 kV / 80 kV Contrast Tube current A/B 21 eff. mAs / 83 eff. mAs Volume 100 ml of 350 mg/ml Dose modulation CARE Dose4D Flow rate 4 ml/s CTDIvol 3.79 mGy Start delay 17 s Rotation time 0.5 s Postprocessing syngo DE LungPBV 58 SOMATOM Sessions · November 2010 · www.siemens.com/healthcare-magazine pulmonary emboli, most pulmonary parenchymal diseases cause tissue den-sities outside the standard range and thus are displayed as perfusion or pseudo-perfusion defects. In the case of emphysema, the cause of the perfusion defects is a true decrease in pulmonary circulation secondary to lung destruc-tion, and it has been reported that the degree of decreased perfusion is corre-lated with the severity of emphysema.* This case also nicely illustrates that high quality, Dual Energy lung scans can be obtained with relatively low radiation dose. The CTDIvol for this exam was 3.79 mGy, resulting in an estimated effective dose of approximately 1.9 mSv. Clinical Results Acute Care * Pausini V, Remy-Jardin M, Faiure JB, et al. “Assessment of Lobar perfusion in smokers according to the presence and severity of of emphysema: preliminary experience with DE”; European Radiology 2009, 19: 2834-2843
- 59. 2 Axial imagesin lung window setting (Fig. 2A and 2C) and cor-responding Dual Energy CT PBV images (Fig. 2B and 2D) show thrombus within the right lower lobe artery with the correspond-ing lung perfusion defect (Fig. 2A and 2B). Severe emphysema-tous changes are present in the left lung. Perfusion is normal within the right upper lobe (Fig. 2C and 2D). Right loculated pleu-ral effusions and diffuse ground glass opacities with septal thick-ening of unknown etiology are also noted. SOMATOM Sessions · November 2010 · www.siemens.com/healthcare-magazine 59 2A 2B 2C 2D 3 Coronal color-coded iodine perfusion map (Fig. 3A) and lung window (Fig. 3B) images show decreased perfusion in the right lower lobe due to acute pulmonary embolism. Scattered perfusion defects in the left lung due to severe emphysematous changes. Also note changes post left upper lobectomy. 3A 3B 1 CTPA sagittal-oblique sub-volume maximum intensity projection (MIP) (Fig. 1A) and sagittal DE CT PBV (Fig. 1B) show large thrombus involving the right lower lobe pulmonary artery (arrow), and near com-plete loss of perfusion of the matching parenchyma with mild narrowing of the pulmo-nary arterial anastomosis (arrowhead). 1A 1B
- 60. Clinical Results AcuteCare Case 12 SOMATOM Defi nition Flash: Rule-Out of Coronary Artery Disease, Aortic Dissection and Cerebrovascular Diseases in a Single Scan Junichiro Nakagawa, MD,* Osamu Tasaki, MD, PhD,* Tomoko Fujihara**and Katharina Otani, PhD** *Trauma and Acute Critical Care Center, Osaka University Hospital, Osaka, Japan **Marketing Division, Healthcare Sector, Siemens Japan K.K., Tokyo, Japan 3A 3B 60 SOMATOM Sessions · November 2010 · www.siemens.com/healthcare-magazine HISTORY An 89-year-old female patient with dis-turbance of consciousness (DOC) and respiratory arrest was brought to the Trauma and Acute Critical Care Center of Osaka University Hospital. She was in shock, her level of consciousness (LOC) was E1V1M2 (Glasgow Coma Scale, GCS) her heart rate was 74 bpm and her blood pressure was unmeasureable. Her anam-nesis included hypertension, and she was on oral medication for diabetes. Her spontaneous breathing was coming back, but her DOC continued, prompting us to perform tracheal intubation and to administer an infusion of vasopressors. She was pulled out of shock. Chest X-ray showed marked enlargement of the cardiac silhouette and a mediasti-nal shadow suggesting congestive heart failure. For a multiple rule-out of coro-nary disease, aortic disease and cerebro-vascular lesions, we performed a Dual Source CT scan in Flash Spiral mode (non-ECG-triggered) from head to tho-racic region. DIAGNOSIS The Dual Source CT images showed heart enlargement, pericardial effusions and left ventricle myocardial hypertro-phy (Fig. 1). None of the three major 1 The Dual Source CT images showed heart enlargement, pericardial effusions and left ventricle myocardial hypertrophy. 1 2 None of the three major coronary arter-ies had stenoses. 2 3 None of the major cerebral arteries were affected.
- 61. 4 5 6 SOMATOM Sessions · November 2010 · www.siemens.com/healthcare-magazine 61 coronary arteries had stenoses (Fig. 2) and no significant abnormity of the aorta or cerebrovascular region (Fig. 3 and 4) was found. With these results, acute cor-onary syndrome, aortic dissection and stroke could be ruled out. The pericar-dial effusion was diagnosed as chronic on echocardiography. Based on the left ventricle myocardial hypertrophy finding, we suspected hypertrophic obstructive cardiomyopathy. A diuretic worked well to improve car-diac function and respiratory condition. After performing tracheotomy, the patient’s respiratory status gradually improved and she could be weaned from ventilatory support after 43 days in the hospital. Her level of consciousness (LOC) came back to E4VTM6 (GCS) and oxygenation could be stopped. On the 48th day, the patient was transferred to another hospital to receive rehabilita-tion. COMMENTS Dual Source CT Flash Spiral was used for long range CT-Angiography (Fig. 5). It gave us necessary information to rule out critical acute coronary syndrome, thoracic aortic dissection and cerebrovas-cular lesions. The Flash Spiral mode is 5 Dual Source CT Flash Spiral was used for long range CT angiography. 6 The fast pitch of 2.3 allows acquiring motion free images in patients who cannot hold their breath. 4 No significant abnormity of the aorta. an extremely useful tool, in particular for ruling out life-threatening disorders at initial treatment phase without hav-ing to subject the patient to additional invasive examinations such as cardiac catheterization. As the Flash Spiral scan mode has a fast pitch of 2.3 (up to pitch 3.4), diagnostic images can be acquired even of patients who cannot hold their breath which is especially useful at Trauma and Acute Critical Care Centers (Fig. 6). EXAMINATION PROTOCOL Scanner SOMATOM Definition Flash Scan mode Flash Thorax Scan area Head to Thorax Scan length 570.5 mm Scan direction Caudo-cranial Scan time 2.07 s Tube voltage 120 kV / 120kV Tube current 162 eff. mAs Dose modulation CARE Dose4D CTDIvol 9.06 mGy DLP 574 mGy cm Rotation time 0.28 s Pitch 2.3 Slice collimation 0.6 mm Slice width 0.75 mm Reconstruction increment 0.6 mm Reconstruction kernel B35f Contrast Volume 95 ml Flow rate 4.0 ml/s Start delay 28 s Bolus Tracking
- 62. Clinical Results AcuteCare Case 13 SOMATOM Defi nition Flash: RIPIT to the Rescue – Fast CT Examination for Trauma Patients Savvas Nicolaou, MD Vancouver General Hospital, Department of Emergency Trauma Radiology, Vancouver, Canada HISTORY A 70-year-old female was involved in a high-speed motor vehicle collision. An auto launch was triggered imme-diately and the patient was transferred by heli cop ter to Vancouver General Hospital (VGH). Immediate imaging was required to quickly ascertain the patient’s condition. A RIPIT FLASH was performed (Rapid Imaging Protocol In Trauma).* DIAGNOSIS The brain demonstrated subarachnoid hemorrhage and small hemorrhagic contusion. A complex LEFORT TYPE 3 VARIANT facial fracture was identified instantaneously. The globes were intact. In addition there was ground glass den-sity in both lower lobes with centrilobular nodular tree in bud appearance, signi-fying aspiration of blood. The abdomen was normal. COMMENTS Given the age and frailty of the patient, an immediate assessment of the patient’s condition was required and this was provided in a matter of seconds with the FLASH RIPIT protocol. 62 SOMATOM Sessions · November 2010 · www.siemens.com/healthcare-magazine The brain findings were not surgical and the complex facial fracture was quickly repaired. The lung findings ensured that the patient was observed with diligence, as this could lead to ARDS.** In the trauma setting, the “golden hour” is critical. If appropriate therapy is instituted then, this can have an important impact on improving patient outcomes by de-creas ing morbidity and mortality. The FLASH RIPIT scan can provide critical, life-saving information in a matter of seconds. EXAMINATION PROTOCOL Scanner SOMATOM Definition Flash Scan area Head to Pelvis Pitch 1.8 Scan length 911 mm Slice collimation 128 x 0.6 mm Scan direction Cranio - caudal Slice width 3 mm Scan time 3.8 s Spatial Resolution 0.33 mm Tube voltage 140 kV Reconstruction increment 1.5 mm Tube current 149 mAs Reconstruction kernel B36f Dose modulation CARE Dose4D Contrast 370 mg/ml CTDIvol 16.53 mGy Volume 150 ml DLP 1596 mGy cm Flow rate 5.0 ml/s Rotation time 0.28 s Start delay 6 s *The RIPID protocol has been introduced in SOMATOM Sessions # 25 by Savvas, Nicolaou in November 2009 **Acute Respiratory Distress Syndrome
- 63. 1, 2 Volume Rendered (VRT) view showing vascular status of this trauma patient. 1 2 3, 4 Fast pitch of 1.8 allows long range scanning from head to pelvis. The sagittal view (Fig. 4) shows artifact free aortic angiogram. 3 4 5 Subarach-noid hemor-rhage delin-eated with a fused MPR (Multi Planar Reformation) and VRT visual-ization tech-nique (arrow). 6 Coronal MPR of the brain (calcu-lated out of the full body scan) shows the extension of the bleeding (arrow). 5 6
- 64. Clinical Results Pulmonology Case 14 Xenon Ventilation CT Scan Demonstrates an Increase in Regional Ventilation After Bullectomy in a COPD Patient By Calvin Yeung W.H., MD and Gladys G. Lo, MD Department of Diagnostic and Interventional Radiology, Hong Kong Sanatorium and Hospital DIAGNOSIS Prior to the examination, a Xenon gas inhalation was initiated. Xenon was also applied during the acquisition to high-light perfusion defects in the lungs. The Xenon Dual Energy examination of the thorax (Figs. 1 and 2) showed dif-fuse emphysema and a large, 9 cm bulla in the left lower lobe. There was a signif-icant 64 SOMATOM Sessions · November 2010 · www.siemens.com/healthcare-magazine decrease in ventilation seen in left lower lobe due to the bulla. Xenon enhancement measurements in left upper lobe showed 44% and in compari-son to the left lower lobe nearly 0% enhancement (Xenon enhancement at trachea is at 100% for reference mea-surements). HISTORY A 70-year-old male (ex-smoker) was referred to the hospital with a history of severe Chronic Obstructive Pulmonary Disease (COPD) with emphysema. A Xenon CT-scan of the thorax was per-formed to assess regional ventilation and plan bullectomy (either broncho-scopic or video assisted surgery). 1 Coronal section of Xenon CT scan of the thorax before bullectomy shows marked decrease in regional ventilation in left lower lobe due to large bulla. 2 Axial section of Xenon CT scan of thorax shows Xenon enhancement in left upper lobe. 1 2
- 65. Pulmonology Clinical Results 4 Axial section of Xenon CT scan of thorax after bullectomy shows Xenon enhancement in left upper lobe increased to 64%. (vs.44% prior to bullectomy) 3 4 SOMATOM Sessions · November 2010 · www.siemens.com/healthcare-magazine 65 COMMENTS With an Xenon CT examination of the thorax, it is possible to demonstrate, in addition to the morphologic assess-ment, the functional state of the lung. In this case it showed less ventilation in the left lower lobe which the bronchos-copist and surgeon used to plan the site for lung volume reduction surgery. Bronchoscopic lung volume reduction surgery was attempted, but failed due to significant collateral flow, detected during the placement of endobronchial valve (one-way valve placed in bron-chius). A video-assisted thoracoscopic bullec-tomy was performed. The bulla in the left lower lobe was surgically resected with no complications and the patient recovered well. After surgery there was a significant subjective improvement in dyspnoea that was confirmed by pul-monary function testing. The Forced Expiratory Volume in 1 second (FEV1) increased from 0.62 l to 0.87 l (25% to 38% of predicted value); FEV1/ Forced Vital Capacity (FVC) ratio increased from 36% to 40%. A value larger than 75% is considered to be normal. In a follow up Xenon CT scan of the thorax (Figs. 3 and 4) a significant improvement of the ven-tilation and function in the left upper lobe was detected. Xenon enhancement measurements in the left upper lobe increased from 44% to 64%. (for refer-ence Xenon enhancement at trachea was 100%). The extremely low dose CT examination utilizing only 1.7 mSv radia-tion dose showed the effect of lung vol-ume reduction surgery with significant improvement in regional ventilation. Bullectomy is a significant treatment in this patient group. Improvements in exercise capacity, pulmonary function and quality of life have been observed in this emphysematous patient, and are attributed to a decrease of (dynamic) hyperinflation. 3 Coronal section of Xenon CT scan of thorax after bullectomy shows increase in volume and ventilation of left upper lobe. Atelectasis and effusion is noted at the bullectomy site. (arrow) EXAMINATION PROTOCOL Scanner SOMATOM Definition Flash Scan mode Dual Energy Lung Scan area Thorax Scan length 310 mm Scan direction Cranio - caudal Scan time 9 s Tube voltage 80kV/140kV Tube current 80 eff. mAs/ 48 eff.mAs Dose modulation CARE Dose4D CTDIvol 3.82 mGy Eff. Dose 1.7 mSv Rotation time 0.26 s Slice collimation 64 x 0.6 mm Slice width 1 mm Spatial Resolution 0.33 mm Reconstruction 0.8 mm increment Reconstruction Kernel D30 Contrast Xenon gas inhalation Start delay 90 s Postprocessing syngo DE Xenon
- 66. Case 15 SOMATOMDefi nition: Dual Energy Locates Progressive Wrist Arthritis By Philipp Weisser, MD, Ralf W. Bauer, MD, J. Matthias Kerl, MD and Thomas J. Vogl, MD Department of Diagnostic and Interventional Radiology, Goethe University Clinic, Frankfurt, Germany 1 Massive, destructive erosions in the wrist, subcortical pre-erosive changes in the MCP-joints (arrow). HISTORY Swelling and pain symptoms in the right hand started 3 months prior to our involvement. Initially there were no pathologic findings in conventional radi-ography and, unfortunately, even a his-topathologic examination was unspe-cific. As the previous radiography to this CT showed massive erosive changes in the wrist, but unclear changes in the MCP (metacarpophalangeal joint) and PIP (proximal interphalangeal joint), we performed a CT scan to search for possible further erosions and synovitis. DIAGNOSIS Rapid progressive wrist arthritis in the right hand. The CT scan revealed mas-sive erosive destruction of the right wrist, accompanied by synovitis and joint effusion. Within the phalanges we found subcortical osteolytic changes (which were not visible in the left hand) with intact cortical structures. With Dual Energy technique, we could easily visualize the synovitic tissue. COMMENTS In rheumatic imaging, when the verifi-cation of erosive changes is the most important question, synovitic tissue can still be easily detected in Dual Energy technique. As the 80/140kV-ratio is quite high, after iodine contrast application it is very easy to visualize this tissue. 66 SOMATOM Sessions · November 2010 · www.siemens.com/healthcare-magazine 1A 1B EXAMINATION PROTOCOL Scanner SOMATOM Definition Scan mode DE Extremity Scan area Dual Energy Wrist Scan length 282 mm Scan direction Cranio - caudal Scan time 21 s Tube voltage A/B 140 kV / 80 kV Tube current A/B 68 mAs / 292 mAs Dose modulation CARE Dose4D CTDIvol 12.97 mGy eff. Dose 0.32 mSv Rotation time 1 s Slice collimation 64 x 0.6 mm Slice width 2 mm Spatial Resolution 0.33 mm Reconstruction 1 mm increment Contrast Volume 90 ml Flow rate 4 ml/s Start delay 360 s Postprocessing syngo DE Gout Clinical Results Orthopedics
- 67. Acute Care ClinicalRe Tsoupltics 2A 2B 2 Distinctive demarcation of synovitis in the right wrist, pronounced Dual Energy characteristics and impressive visualization of the synovitis (arrow). 3A 3B 3 3D Fusion rendering, showing the destructions and synovitis of the right wrist (arrow). 4A 4B 4 Difference of density in synovitis after application of iodine contrast agent at 80 and 140 kV. We measured around 140 HU in 80 kV, and around 90 HU in 140 kV (arrow). SOMATOM Sessions · November 2010 · www.siemens.com/healthcare-magazine 67
- 68. Science Dose Parametersand Advanced Dose Management on SOMATOM Scanners The measurement and calculation of radiation dose in CT is an important topic for an effi cient dose management. Quantities such as the CTDI, DLP and effective dose are useful when used appropriately. Now Siemens takes dose management to a new level by providing tools such as Dose Structured Reports and CARE Analytics. By Stefan Ulzheimer, PhD, Christianne Leidecker, PhD, and Heidrun Endt Business Unit CT, Siemens Healthcare, Forchheim, Germany The assessment and management of patient dose has become one of the most frequently discussed topics in Computed Tomography. On SOMATOM Scanners, the reporting of established dose para-meters like Computed Tomography Dose Index (CTDI) and Dose Length Product (DLP) has been implemented since 1999. For each exam, the information is avail-able in the patient protocol, and can be viewed and archived as a DICOM image. With Dose Structured Reports (Dose SR) Siemens is taking the next step to enable more transparency in terms of radiation dose. Furthermore, tools like CARE Analytics provide an easy means to eval-uate Dose SR. Technical dose parameters – CTDIvol and DLP The CTDI is the primary dose measure-ment concept in CT and is defined by the International Electrotechnical Com-mission (IEC) [1] and adopted by various national bodies such as for example by the US Food and Drug Administration (FDA). The weighted volume CT Dose Index, CTDIvol represents the average Calculating effective dose from scanner dose information. 68 SOMATOM Sessions · November 2010 · www.siemens.com/healthcare-magazine absorbed dose within the scan volume for standardized phantoms. Their diame-ters are 16 and 32 cm, to approximate conditions for head and body examina-tions so the phantoms do not adequately represent patient cross-sections. How-ever the CTDIvol is an objective technical dose parameter based on a directly mea-sured quantity. It takes into account pro-tocol- specific parameters and is useful to compare different scan protocols across various CT scanners. Thus, IEC standards require the prospective display of the CTDIvol on the console of the CT scanner. 1 Calculating effective dose for adults. From the Patient Protocol of this abdominal scan, the DLP is obtained: DLP = 274 mGy·cm Using the conversion factor for abdominal exams, 0.015 mSv/(mGy·cm) [3], effective dose E is estimated to be E = 274 mGy·cm · 0.015 mSv/(mGy·cm) = 4.1 mSv 1
- 69. Science Calculating effectivedose from scanner dose information for a pediatric body exam. 2 Calculating effective dose for children. Using the same values as in the first example, the DLP is: DLP = 274 mGy·cm. First you have to determine if the DLP refers to a 32 cm or 16 cm CTDI phantom. In this case, the DLP is reported in the 32 cm body CT dose phantom. This value has to be converted to the head CT dose phantom if pediatric conversion factors published in [table 1] shall be used to compute the effective dose: DLP = 2.0 * 274 mGy·cm = 548 mGy·cm. Note: Typical values are between 2.0 and 2.4 for Siemens scanners. Values can be found in the System Owner Manual. Since the method of using conversion factors to determine the effective dose is a very rough method usually using a cor-rection factor of 2.0 is sufficiently accurate for all scanners. For a 5-year old child, a factor of 0.02 mSv/(mGy·cm) for abdominal exams is used [table 1] to estimate E. E = 548 mGy·cm · 0.02 mSv/(mGy·cm). = 11 mSv. If the DLP was already measured in the 16 cm head phantom like it is the case on new scanners the conversion factors from table 1 can be used directly without applying an additional factor of 2.0 to 2.4. SOMATOM Sessions · November 2010 · www.siemens.com/healthcare-magazine 69 To represent the overall dose of a given scan protocol, the CTDIvol is multiplied with the examination range which then yields the DLP. Towards assessing patient dose When asking the question of “what is the radiation dose”, one really is inter-ested in “what is the risk of this exam”? However, information on individual patient dose depends on multiple para-meters, such as patient specific character-istics and in addition to the technical parameters of the system and exam. The International Commission on Radia-tion Protection (ICRP) has introduced the concept of effective dose which repre-sents a risk-related quantity for the con-trol of radiation exposure and optimiza-tion of protection. It cannot be measured directly, but rather is calculated using defined dosimetric models. Hence, it applies to a reference person and does not provide risk information for the individual. Table 1 Region of body Conversion factor from DLP to Effective Dose in [mSv / (mGy ·cm)] 0 year old 1 year old 5 year old 10 year old Adult Head and neck 0.013 0.0085 0.0057 0.0042 0.0031 Head 0.011 0.0067 0.0040 0.0032 0.0021 Neck 0.017 0.012 0.011 0.0079 0.0059 Chest 0.039 0.026 0.018 0.013 0.014 Abdomen and pelvis 0.049 0.030 0.020 0.015 0.015 Trunk 0.044 0.028 0.019 0.014 0.015 One practical method to calcu-late effective dose: Conversion factors from DLP to effective dose for children and adults; for different body regions as published in [2, 3]. Please note that the conversion factors for children refer to a DLP measured in a 16 cm phantom. On older scanners or software versions the DLP in pediatric protocols often refers to a 32 cm phantom. Then an additional correction factor has to be applied. 2
- 70. Science 3 TheDose SR can be viewed on the scanner console, sent to PACS or to an independent server used to mon-itor dose data. 3 Practical ways to determine effective dose for CT exams Several approaches to estimate effective dose for CT exams have been investi-gated. A generic method was proposed to estimate effective dose from the DLP of an exam [2], with the DLP being reported on most systems. Conversion factors for normalized effective dose per DLP were obtained from Monte Carlo calculations of effective dose for various clinical exams. These conversion factors depend only on the region of the body being scanned (head, neck, thorax, abdomen, or pelvis). It is important to understand that calcu-lating effective dose using this method can always only be a rough estimate of effective dose because many parameters that influence effective dose are not taken into account. The body size and the exact location of the scanned area in relation to the dose sensitive organs are only two of those parameters. However, usually this method is sufficiently exact for the purpose the effective dose con-cept was developed for: Radiation protec-tion and getting an estimate on the total exposure that is also comparable with other sources of radiation. As an example, Figure 1 illustrates the calculation of the effective dose of an abdominal scan using conversion factors published by Shrimpton et al. [table 1]. Special considerations for children Conversion factors are also available for children of various ages [table 1]. Special attention has to be paid to the fact that the conversion factors published apply to values reported in the head CT 70 SOMATOM Sessions · November 2010 · www.siemens.com/healthcare-magazine dose phantom. In the past scanners, CTDI values were reported in the head CT dose phantom for head exams and the body CT dose phantom for body exams, irrespective of the patient age. This was in line with the original IEC standards, which did not provide instructions for pediatric exams. Thus, for calculations regarding pediatric body exams, an additional calculation step has to be performed, as illustrated in Figure 2. The example shown illustrates that the same exposure leads to an effective dose that is almost three times higher for a five year old than an adult. While being purely theoretical, the example shows that, it is of utmost importance to pay special attention when imaging pediatric patients, in particular to use dedicated pediatric protocols in combination with
- 71. Science References 1IEC 61223-2-6 Evaluation and routine testing in medical imaging departments – Part 2-6: Con-stancy tests – Imaging performance of computed tomography X-ray equipment 2 Jessen KA, Panzer W, Shrimpton PC, et al. EUR 16262: European Guidelines on Quality Criteria for Computed Tomography. Paper presented at: Office for Official Publications of the European Communities; Luxembourg. 2000. 3 Shrimpton PC, Hillier MC, Lewis MA, Dunn M. National survey of doses from CT in the UK: 2003. Br J Radiol Dec;2006 79(948):968–980. [PubMed: 17213302] SOMATOM Sessions · November 2010 · www.siemens.com/healthcare-magazine 71 CARE Dose4D. To standardize dose reporting for pediat-ric patients, future editions of IEC stan-dards will require dose reporting in the head CT dose phantom for pediatric exams, irrespective of the body region imaged. Starting with software version syngo CT 2011A, Siemens will implement this new requirement. As a consequence, the conversion factors [table 1] can be directly applied also in pediatric proto-cols. To ease the transition, the CT dose phantom size was added to the user interface and it is also reported in the Dose SR. A new standard: Dose Structured Reports As the first CT manufacturer Siemens now provides the new Dose SR almost across its complete CT product portfolio. The Dose SR contains comprehensive data for each irradiation event, the accu-mulated dose and information about the context of the exposure. The data is pro-vided in electronic format that can be sent to any system which receives, stores or processes dose information, such as conventional PACS or workstations. A new tool to evaluate Dose Structured Reports: CARE Analytics The Dose SR can serve as the center piece of an institution wide dose quality control. To evaluate and analyze the information, Siemens provides a new free tool, CARE Analytics. It is a stand-alone tool and can be installed on an office computer. With CARE Analytics, one can query Dose SR from DICOM nodes directly. Dose reporting data can be exported and ana-lyzed with standard tools, such as Micro-soft Excel™. With the prompt implementation of Dose SR and the new tool CARE Analytics Siemens provides the customer with all the information needed for a transpar-ent dose management.
- 72. Science IRIS andFlash: Cardio CT with Minimum Radiation Exposure Delivers Precise Images Iterative Reconstruction in Image Space (IRIS) in connection with the SOMATOM Defi nition Flash can provide extremely high speed CT examina-tions of the heart, with a radiation dose of less than 0.5 mSv. A recent study of the German Heart Centre Munich demonstrates the high image quality of this method. This opens up the prospect of using CT more extensively in cardiological investigations than has been the case to date. By Matthias Manych The coronary vessels of the heart have a diameter of just a few millimeters. In order to study these vessels and to diagnose and quantify arteriosclerotic changes in CT, images with high resolu-tion in space and time are required. Until a few years ago, however, these could only be obtained with relatively high doses of radiation. The challenge of com-bining brilliant diagnostic images with a minimum of radiation exposure for patients has now been met successfully with new scanner technologies. In par-ticular at cardiology centers with a great deal of expertise, these developments have brought about a marked improve-ment for Cardio CT, according to Dr. Jörg Hausleiter, specialist in non-invasive, cardiac CT diagnostics at the German Heart Centre Munich. He explains: “The data at our center shows that three or four years ago, we had an average effec-tive radiation exposure of 10 mSv; now, we are at under 2 mSv.” New dimension of low-dose CT using IRIS A number of approaches to image data processing have been developed as part of the quest to reduce radiation expo-sure without loss in image quality. Among other approaches, these efforts involved feeding the raw data measured by the scanner back into a mathematical correc-tive loop in order to reconstruct the best possible image through incremental approximations. Siemens has now sup-plied IRIS as an innovative reconstruction option, which has been analyzed by Haus-leiter (together with Dr. Bettina Gramer and Dr. Bernhard Bischoff). With this study, the medical scientist aimed to establish the level of image quality that can be achieved with IRIS in low-dose Cardio CT. To this end, the method was compared to Filtered Back Projection (FBP), the standard in CT image recon-struction. 72 SOMATOM Sessions · November 2010 · www.siemens.com/healthcare-magazine Hausleiter describes the initial situation: “You have to consider that the quality of conventional image recon-struction has already reached a level of perfection where it is essentially diffi-cult to raise the standard any higher.” First of all, the lung arteries of 56 patients were depicted. In a subgroup of 36 patients who had a heart rate of less than 60 beats per minute, the coronary vessels were also assessed. The physi-cians did so using the specific capabili-ties of the SOMATOM Definition Flash, which they had helped develop. The Flash mode operates with extreme rapidity; temporal resolution amounts to just 75 ms, and scanning of the entire chest takes only 0.6 s. In this way, even the fine structures of the beating heart can be captured in precise images. IRIS has proven its worth. Despite the remarkably low radiation level of only 0.5 mSv, the assessibility of the CT images was evaluated at 100 per cent. As far as diagnostics is concerned, the new reconstruction technique is just as good as FBP. In terms of the quantita-tive quality criteria such as image noise and signal-to-noise ratio, IRIS even showed statistically significant superior-ity. Jörg Hausleiter is very satisfied with the outcome of the study, which was PD Hausleiter, MD, is physician for internal medicine and cardiology and director at the German Heart Center in Munich.
- 73. 1 A 55-yearold man under-went coronary CT Angiography with the SOMATOM Definition Flash to exclude a stenosis of the pulmonary vein before cardiac electrophysiology examination. In combination with IRIS the CT scan could be carried out with an extremely low dose of 0.5 mSv (DLP 39 mGy cm). (Courtesy of PD Hausleiter, MD, German Heart Center, Munich, Germany) SOMATOM Sessions · November 2010 · www.siemens.com/healthcare-magazine 73 presented in May this year at the Interna-tional Symposium on Multi-detector Row CT in San Francisco: “IRIS and Flash pro-vide us with very potent instruments for keeping radiation exposure as low as possible. At the same time, the resulting images are of high diagnostic value. The two methods complement one another very well, and our results are very prom-ising.” Also, as the cardiologist points out, IRIS can be used with a less powerful CT scanner, which nevertheless will deliver better images than have been available to date. A new perspective for cardiac diagnostics IRIS reduces image noise and artifacts very effectively without loss in spatial resolution. Together with state-of-the-art scanner technology, radiation expo-sure in Cardio CT can be reduced to levels well below those in scintigraphy and cardiac catheterization. This removes one of the main points of criticism against CT, which may now take on a new impor-tance in cardiac diagnostics. Cardiac catheterization is still quite widespread; in Germany alone, the method is employed about 700.000 to 800.000 times a year. As Hausleiter points out, however, many cases are without patho-logical findings, and only 25 to 30 per cent of patients must undergo balloon dilatation during invasive cardiac imag-ing. Thus, it should certainly be possible to replace part of these catheterization procedures with CT diagnosis. High radiation exposure has been an obstacle to cardiological screening so far. Now, with the possibilities offered by IRIS and Flash, the discussion should receive a fresh impetus. Against the background of cardiovascular diseases as the leading cause of death, Hausleiter says: “This is certainly worth considering as a concept for employing such technologies in screening in selected patient groups with a higher risk of coronary events.” Matthias Manych has a master’s degree in Biology and is a freelance scientific journalist and editor with a focus on medicine. In addition to other topics, he regularly covers develop-ments in imaging technology. 1 Science
- 74. Life Clinical Fellowship:Learning From the Experts in the Field You are eagerly awaiting the arrival of a new CT scanner and are a little ner-vous about the new options and features? Then this is the perfect moment to attend a Clinical Fellowship program, an educational format Siemens Healthcare offers to users of their CT scanners and applications. They pro-vide the opportunity to improve your skills while being guided through the daily clinical workfl ow at an institution. By Wiebke Kathmann, PhD Dr. Ralf Bauer (left) and Dr. Matthias Kerl (right) are in charge of the CT fellowship program at Johann Wolfgang Goethe University in Frankfurt/ Germany. 74 SOMATOM Sessions · November 2010 · www.siemens.com/healthcare-magazine
- 75. SOMATOM Sessions ·November 2010 · www.siemens.com/healthcare-magazine 75 Application training and clinical hands-on workshops are valuable opportunities to learn more about the features of a new CT scanner. But they do not repre-sent the clinical reality. Choice of proto-col, critical determinants of the work-flow or contrast injection timing were some of the questions that remain open even for an experienced radiologist like Naama Bogot, MD, Jerusalem, Israel. That is why she decided to register for a Clinical Fellowship at Siemens once it was sure that her department would be getting a SOMATOM Definition Flash. At the time, she had been working for nine years as a radiologist specialized in car-dio thoracic imaging and was employed at a private institute that is affiliated with the Hebrew University. The fellow’s perspective Bogot had a clear agenda on her mind when arriving at the radiology depart-ment of the Johann Wolfgang Goethe University in Frankfurt Main, Germany: “My aim was not to use the fantastic new scanner like any other scanner but to get the most out of it, to use it in an educated way. I also wanted to under-stand when to choose a single or a dual source mode and when to use flash scan-ning. How to avoid mistakes in using the technical features and protocols and how to best perform Dual Energy CT imaging.” There was more on her list. Bogot also wanted to deepen her understanding of the chemical and physical properties of tissues when applying two levels of energy as in Dual Energy CT and on how to use different levels of radiation in car-diac CT imaging. Timing of contrast injec-tion was another issue on her agenda. “With the SOMATOM Definition Flash scanner being so fast there is little time for planning the injection.” Besides, she felt she needed to learn about dose in cardiac CT imaging, as the radiation dose needed with the SOMATOM Definition Flash is far lower than with any other scanner. “Dosing aspects and safe dosing are a hot topic for me. I learned a lot.” Good learning experience Frankfurt was the center of choice for Bogot as it is very versatile, offering for more refined examinations. Last, but not least, the radiation dose is a big issue: “We teach fellows how to get the maximum result with the least radiation dose, because dose has become a big issue for patients.” In Frankfurt, fellows can learn a wide array of applications of Dual Energy scanning, be it cardiovascu-lar imaging, diagnosis of lung emboli, cardiac diagnosis with flash, sequence or dual energy modus, angio CT or onco-logical issues. “We do the whole spec-trum of diagnostic radiology from head-neck scans to trauma diagnosis to angio CT from head to toe,” says Kerl. “That way, the fellow can experience the scan-ner as an all-round-machine.” Looking back, Bogot would recommend other fellows to plan on two visits. One 5-day and another 3- to 5-day visit some months later after trying out the proto-cols back home. “The second time one is more focused on what to ask and observe.” She herself would love to go back in two months. Wiebke Kathmann, PhD, is a frequent contribu-tor to medical magazines. She holds a Master in Biology and a PhD in Theoretical Medicine and was employed as an editor for many years before becoming a freelancer in 1999. She is based in Munich, Germany. tumor diagnosis and intervention as well as cardiac imaging and other applica-tions. Besides, the academic point of view and innovative applications had sparked her interest when meeting Ralf Bauer, MD, and Matthias Kerl, MD, at a hands-on workshop earlier in the year. Bogot came to Frankfurt for a week. The stay fulfilled all of her expectations. She managed to look into all the aspects she had wanted to study and even set up a research collaboration with Bauer and Kerl. Bogot very much appreciated the enthusiasm of both experts in Frankfurt. “Being at the beginning of their career they were both very enthusiastic about the scanner, eager and open to share and skilled in their teaching while I could contribute my clinical experience as a radiologist. The learning atmo-sphere was good and reciprocal.” Upon leaving Frankfurt, Bogot felt confi-dent and competent about working with the new scanner back in Israel. Her con-clusion: “The learning curve was a lot faster than if I had had to figure it all out by myself.” Bogot would recommend fel-low radiologist to take advantage of this option, provided they are motivated and have some background. The experts’ perspective For Bauer and Kerl, Bogot was not the first Clinical Fellow. By now they have shared their expertise with ten attend-ees. Both enjoy this format and appreci-ate the insights they get into the work, workflow or applications used in other hospitals or the health system in other countries. Upon arrival of a fellow, Bauer and Kerl first discuss the fellows expecta-tions and find out about his or her clinical focus back home. Both can differ quite a bit as Frankfurt offers this format to tech-nicians as well as radiologists. “Some of our fellows are already experienced in working with Siemens CT scanners, most have already done the Application Train-ing. Others want to learn about post pro-cessing after buying a new software.” Bauer’s and Kerl’s goal is to send attend-ees home with a set of robust protocols for routine applications, to provide them with tips and tricks for daily clinical prac-tice and to teach them subtle nuances “I want to get the most out of the new scan-ner and use it in the most educated way.” Dr. Naama Bogot, Department of Radiology, Shaare Zedek Medical Center Jerusalem, Israel and Department of Radiology, University of Michigan Hospital, Ann Arbor Michigan, USA
- 76. Life STAR: SpecializedTraining in Advances in Radiology By Axel Lorz, Business Unit CT, Siemens AG, Healthcare Sector, Forchheim, Germany eminent leaders in their field who have hands-on expertise . The lecture topics are jointly selected by the local represen-tatives and are tailored to country-specific requirements. STAR’s unique approach is that it is run without com-mercial overtones, which is guaranteed by the close cooperation with indepen-dent advisors. For the past six years, Prof. Hans Ringertz from Linköping Uni-versity, Sweden and Stanford University, USA, has successfully headed the program as Scientific Director. By the end of 2010, close to 140 STAR events were held in STAR is an international educational forum jointly sponsored by Bayer Schering Pharma and Siemens and was launched way back in 1993. Its aim is to train practicing radiologists by offering a wide range of topics ranging from refresher type courses to cutting-edge develop-ments in radiology. The program sym-posia are held as regular forums in the respective country in conjunction with local radiological societies. The meetings typically last two days and consist of 45-minute faculty lectures – followed by 90 to 120-minute workshops – by five 76 SOMATOM Sessions · November 2010 · www.siemens.com/healthcare-magazine www.star-program.com Evolve Update Facilitates Dose Savings By Marion Meusel, Business Unit CT, Siemens Healthcare, Forchheim, Germany protocols to improve gray-white matter differentiation and therefore to achieve better contrast without an increase in noise or dose. Furthermore syngo CT 2010A offers new purchasable features like IRIS (Iterative Reconstruction in Image Space), X-CARE and the Hi-Pitch Spiral scan mode. IRIS uses multiple iteration steps for the reconstruction of CT data while reducing image noise with syngo Evolve, Siemens’ non-obsole-scence program, ensures latest soft ware and hardware upgrades for your medical equipment. Currently SOMATOM Definition cus-tomers with an Evolve contract enjoy the upgrade to syngo CT 2010A. Those customers will benefit from enhance-ments such as Neuro BestContrast integrated in the head and neuro scan 35 different countries with more than 23,000 radiologists attending. STAR is one example of Siemens´ ongoing sup-port for the professional education of radiologists. To learn more on STAR, the following link can be consulted. The image shows stan-dard reconstruction using conventional body kernel scanned at 1.4 mSv. (Fig. 1A). Here, the initial 1.4 mSv scan was recon-structed with IRIS. Curved planar reformation of the right coronary artery (RCA) showing signifi-cantly sharper visualiza-tion of calcifications with IRIS (Fig. 1B). every step and thus allowing up to 60 % lower radiation dose and/or improving image quality. X-CARE enables organ-sensitive dose protection by reducing sensitive area exposure up to 40% with-out loss of image quality. The Hi-Pitch Spiral scan mode for a maximum pitch of 3.2 at a maximum scan speed of 96 mm/s will drastically shorten the scan time and eliminate motion artefacts, thus being very useful in paediatric scanning. To discover more on the CT clinical application portfolio visit: International: www.siemens.com/DiscoverCT USA only: www.usa.siemens.com/ webShop/CT 1A 1B
- 77. Life SOMATOM Sessions· November 2010 · www.siemens.com/healthcare-magazine 77 Frequently Asked Questions By Ivo Driesser, Business Unit CT, Siemens Healthcare, Forchheim, Germany and provides a slightly higher dose in the posterior part of the body. The dose distribution is changed in favor of the dose sensitive organ. How to use X-CARE? The dedicated, default scan protocols in the patient model dialog are marked with the suffix “XCARE” (for example: Thorax_XCARE or Head_XCARE). How to know if X-CARE is used? On the Routine subtask card there is a watermark displaying the gantry. A green zone visualizes the area of the dose protection (Fig. 1). When the patient position is changed in the Patient Model X-CARE is an organ-sensitive dose pro-tection feature. With X-CARE, organs which are more sensitive to radiation, like eye lenses and breast tissue, re ceive a lower dose. This feature is introduced by Siemens Healthcare in the latest software update (syngo CT 2010A) for SOMATOM Definition and SOMATOM Definition Flash. How does it work? X-CARE intelligently changes the dose distribution during a rotation. It lowers the tube current, and therefore dose, in the area of a sensitive organ (anterior) On the subtask card, the X-CARE zone is visualized on the watermark. Siemens Healthcare is Proud to Present a New Series of Live Clinical Webinars By Heike Theessen, Business Unit CT, Siemens Healthcare, Forchheim, Germany In the first session, Prof. Stephan Achen-bach, MD from Erlangen University will present a current status report on low dose imaging in the field of cardiac CT. Prof. Achenbach will present many clini-cal cases with excellent image quality acquired with a minimum of radiation dose. Each webinar session is recorded and available online for later review. More clinical webinars are planned so don’t wait and please register now for further information. Siemens Healthcare is proud to present a new series of live clinical webinars. These Webinars are ideal for CT users who are interested in finding the latest infor-mation in healthcare imaging, discover-ing new technologies and gaining access to some of the worlds most renowned clinicians. And all of this is possible with-out the need to travel and completely free of charge. Every month a different clinical modality will be featured to show what is new in the exciting field of medical imaging. The opportunity can be taken to interact with the expert clinicians. Dialog, the X-CARE zone adapts auto-matically. That means that the X-CARE zone is always placed on the anterior part of the body. In the comment line there is also the entry “X-CARE”. What about obese patients? X-CARE checks the patient size for every individual patient and creates the best dose distribution so that the best possible image quality is guaranteed. How to get X-CARE? Your Siemens contact representative will be happy to help you arrange for free trial licenses. www.siemens.com/webinars 1 1
- 78. Life Clinical Workshops2011 As a cooperation partner of many renowned hospitals, Siemens Healthcare offers continuing CT training programs. A wide range of clinical workshops keeps participants at the forefront of clinical CT imaging. Workshop Title Date Location Course Lan-guage Course Director Clinical Workshop on Cardiac CT/ Munich April 6 – 8, 2011 July 20 – 22, 2011 October 4 – 6, 2011 Munich, Germany 78 SOMATOM Sessions · November 2010 · www.siemens.com/healthcare-magazine English Prof. Christoph Becker, MD PD Thorsten Johnson, MD Alexander Becker, MD Fabian Bamberg, MD Clinical CTA Interpretation Course/ Erlangen January 13 – 14, 2011 March 24 – 25, 2011 June 30 – July 1, 2011 Erlangen, Germany English Prof. Stephan Achenbach, MD Clinical Training Course on Cardiac CT March 12 – 13, 2011 September 10 – 11, 2011 Kuching, Malaysia English Prof. Sim Kui Hian, MD Ong Tiong Kiam, MD Dual Energy Workshop May 6 – 7, 2011 September 16 – 17, 2011 Forchheim, Germany English PD Thorsten Johnson, MD News at Educate Homepage: Recommended CT Literature By Heike Theessen, Business Unit CT, Siemens Healthcare, Forchheim, Germany like to recommend these books to physi-cians and technologists who want to get a more detailed insight into the technol-ogy of CT, cardio-vascular or oncologic CT applications. With this comprehensive overview, which will grow over time and be con-stantly updated, you will always have the latest CT-related book publications to further improve clinical know-how right at your finger tips. On the Educate Homepage, the authors names can be found as well as book titles and order numbers with a forward-ing link for convenient online ordering. A new section on Siemens CT’s Educate Homepage supports users with recom-mendations about CT literature. When it comes to clinical training, Siemens strongly relies on an indepen-dent network of CT professionals. These collaboration partners support fellow-ships and workshops throughout the year and many of them are very active in the CT scientific arena as well. As a result of this scientific work, numerous books have been published recently by well-known CT luminaries, sharing their knowledge and experience. As part of the education offerings, Siemens would www.siemens.com/ SOMATOMeducate
- 79. Life ESGAR CT-ColonographyWorkshops April 13 – 15, 2011 September 14 – 16, 2011 Dublin, Ireland Gothenburg, Sweden Title Dates Short Description Location Contact SOMATOM Sessions · November 2010 · www.siemens.com/healthcare-magazine 79 RSNA November 28 – December 3, 2010 Annual Meeting of Radiological Society of North America Chicago, USA www.rsna.org Arab Health January 24 – 27, 2011 Arab Health Congress Dubai, UAE www.arabhealthonline. com International Stroke Confer-ence February 9 – 11, 2011 Present recent scientific work related to stroke and cerebrovas-cular disease Los Angeles, USA http://strokeconference. americanheart.org/portal/ strokeconference/sc/ ECR March 3 – 7, 2011 European Society of Radiology Wien, Austria www.myesr.org AHA March 22 – 25, 2011 Cardiovascular Epidemiology and Prevention Scientific Sessions Atlanta, USA www.americanheart.org ACC April 3 – 5, 2011 American College of Cardiology New Orleans, USA www.acc.org ITEM April 8 – 10, 2011 International Technical Exhibition of Medical Imaging Yokohama, Japan www.jira-net.or.jp AOCR April 11 – 15, 2011 American Osteopathic College of Radiology Palm Beach, USA www.aocr.org DGK April 27 – 30, 2011 German Cardiac Society Annual Meeting Mannheim, Ger-many www.dgk.org DRK June 1 – 4, 2011 German Radiology Congress Annual Meeting Hamburg, Germany www.roentgenkongress.de ASNR June 4 – 9, 2011 49th Annual Meeting of the National Society of Neuroradiology Seattle, USA www.asnr.org ISCT June 13 – 16, 2011 International Symposium on Multidetector Row CT San Francisco, USA www.isct.org SCCT July 14 – 16, 2011 Society of Cardiovascular Computed Tomography Denver, USA www.scct.org Upcoming Events & Congresses English Prof. Helen Fenlon, MD Martina Morrin, MD Prof. Mikael Hellström, MD Experience Lounge at ECR 2011 March 3 – 7, 2011 Vienna, Austria English Siemens Healthcare Hands-on Tutorials at ESC 2011 August 27 – 31, 2011 Paris, France English Siemens Healthcare In addition, you can register and fi nd the latest CT courses offered by Siemens Healthcare at www.siemens.com/SOMATOMEducate
- 80. Subscription Siemens HealthcarePublications Our publications offer the latest information and background for every healthcare fi eld. From the hospital director to the radiological assistant – here, you can quickly fi nd information relevant to your needs. Medical Solutions Innovation and trends in healthcare. The magazine, published three times a year, is designed especially for members of the hospital management, administration per-sonnel, and heads of medical departments. AXIOM Innovations Everything from the worlds of interventional radiology, cardiology, fluoroscopy, and radiography. This semi-annual magazine is primar-ily designed for physicians, physicists, researchers, and medical technical personnel. MAGNETOM Flash Everything from the world of magnetic resonance imaging. The magazine presents case reports, technology, product news, and how-to’s. It is primarily designed for physicians, physicists, and medical technical personnel. News Our latest topics such as product news, reference stories, reports, and general interest topics are always available at www.siemens.com/ healthcare-news For current and prior issues and to order the magazines, please visit www.siemens.com/healthcare-magazine 80 SOMATOM Sessions · November 2010 · www.siemens.com/healthcare-magazine SOMATOM Sessions Everything from the world of computed tomography. With its innovations, clinical applications, and visions, this semiannual magazine is primarily designed for physicians, physicists, researchers, and medical technical personnel.
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SOMATOM Sessions · November 2010 · www.siemens.com/healthcare-magazine 81 SOMATOM Sessions – IMPRINT © 2010 by Siemens AG, Berlin and Munich All Rights Reserved Publisher: Siemens AG Healthcare Sector Business Unit Computed Tomography Siemensstraße 1, 91301 Forchheim, Germany Chief Editors: Monika Demuth, PhD (monika.demuth@siemens.com) Stefan Ulzheimer, PhD (stefan.ulzheimer@siemens.com) Clinical Editor: Andreas Blaha (andreas.blaha@siemens.com) Project Management: Sandra Kolb Responsible for Contents: André Hartung Editorial Board: Andreas Blaha Andreas Fischer Stefan Ulzheimer, PhD Peter Seitz Stefan Wünsch, PhD Axel Lorz Julia Hölscher Jan Freund Heidrun Endt Authors of this issue: Nils Dahlström, MD, Petter Quick, Pia Säfström, MD, Susann Skoog, MD, Department of Radiology and Center for Medical Image Science and Visualization (CMIV), Linköping University Hospital, Linköping, Sweden Kheng-Thye Ho, FACC, Kia-Chong Chua, MSC, Department of Cardiology, Tan Tock Seng Hospital, Singapore, Republic of Singapore Wolfgang Gerlach, MD, Private Practice, Heidenheim, Germany Lucía Flors, MD, Klaus D. Hagspiel, MD, Carlos Leiva-Salinas, MD, Department of Radiology, University of Virginia, VA; USA João Carlos Costa, MD, J. Dinis, MD, R. Duarte, MD, J. Oliveira, MD, O. Borlido, RT, M. Gonçalves, RT, D. Martins, RT, S. Silva, RT, D. Teixeira, RT, Radiology Department, Hospital Particular de Viana do Castelo, Viana do Castelo, Portugal Dominik Augart, MD, Christoph Becker, MD, Barbara Wieser, MD, Department of Radiology, Ludwig-Maximilians- University, Munich, Germany Philipp Gölitz, MD, Department of Neuroradiology, University of Erlangen- Nuremberg, Erlangen, Germany Masahiro Higashi, MD, PhD, Hiroaki Naito, MD, PhD, Tetsuro Nakazawa, MD, Department of Radiology, National Cardiovascular Center, Osaka, Japan Savvas Nicolaou, MD, Vancouver General Hospital, Department of Emergency Trauma Radiology, Vancouver/Canada Junichiro Nakagawa, MD, Osamu Tasaki, MD, PhD, Trauma and Acute Critical Care Center, Osaka University Hospital, Osaka, Japan Gladys G Lo, MD, Calvin Yeung W.H., MD, Department of Diagnostic and Interventional Radiology, Hong Kong Sanatorium and Hospital Ralf W. Bauer, MD, J. Matthias Kerl, MD, Thomas J. Vogl, MD, Philipp Weisser, MD, Department of Diagnostic and Interventional Radiology, Goethe University Clinic, Frankfurt, Germany Ron French, Healthcare writer; Hildegard Kaulen, PhD, freelance scientifi c journalist; Wiebke Kathmann, PhD, freelance journalist; Michaela Spaeth- Dierl, medical editor, Spirit Link Medical; Rudolf Hermann, journalist; Sameh Fahmy, freelance medical and technology journalist; Reinaldo José Lopes, science editor; Christian Rayr, independent journalist; Matthias Manych, freelance scientifi c journalist and editor; Tony de Lisa, freelance author Ernst Klotz, PhD; Christoph Pankin; A. Chaves, Tomoko Fujihara; Katharina Otani, PhD; Heidrun Endt; Stefan Ulzheimer, PhD; Jan Freund; Stefan Wünsch, PhD; Peter Aulbach; Heike Theessen; Doris Pischitz; Christianne Leidecker, PhD; Marion Meusel; Ivo Driesser; Axel Lorz; Bernhard Krauss; Andreas Blaha; Tanja Gassert; Sami Atiya, PhD; Larry Gallone; Jakub Mochon; Lorin Gorton; Stéphane Le Roy; all Siemens Healthcare Photo Credits: Thorsten Rother, Jez Coulson/Insight- Visual, Johannes Krömer, Philip Singer/ Agentur Anzenberger, Jeann-Luc Bertini/ Agentur Focus, Douglas Engle/Aurora Photos, Stephan Sam Production and PrePress: Norbert Moser, Kerstin Putzer, Siemens AG, Healtchare Sector Desing and Editorial Consulting: Independent Medien- Design, Munich, Germany In cooperation with Primafi la AG, Zurich, Switzerland; Managing Editor: Christa Löberbauer; Photo Editor: Susanne Nips; Layout: Claudia Diem, Mathias Frisch All at: Widenmayer straße 16, 80538 Munich, Germany The entire editorial staff here at Siemens Healthcare extends their appreciation to all the experts, radiologists, scholars, physicians and technicians, who donated their time and energy – without payment – in order to share their expertise with the readers of SOMATOM Sessions.
- 82. www.siemens.com/healthcare-magazine On accountof certain regional limitations of sales rights and service availability, we cannot guarantee that all products included in this brochure are available through the Siemens sales organization worldwide. Availability and packaging may vary by country and is subject to change without prior notice. Some/All of the features and products described herein may not be available in the United States. The information in this document contains general technical descriptions of specifications and options as well as standard and optional features which do not always have to be present in individual cases. Siemens reserves the right to modify the design, packaging, specifications and options described herein without prior notice. Please contact your local Siemens sales representative for the most current information. Note: Any technical data contained in this document may vary within defined tolerances. Original images always lose a certain amount of detail when reproduced. Global Business Unit Siemens AG Healthcare Sector Computed Tomography Siemensstraße 1 91301 Forchheim Germany Phone: +49 9191 18 - 0 www.siemens.com/healthcare Local Contact Information Asia/Pacific: Siemens Medical Solutions Asia Pacific Headquarters The Siemens Center 60 MacPherson Road Singapore 348615 Phone: +65 9622 - 2026 www.siemens.com/healthcare Canada: Siemens Canada Limited Healthcare Sector 2185 Derry Road West Mississauga ON L5N 7A6 Canada Phone: +1 905 819 - 5800 www.siemens.com/healthcare Europe/Africa/Middle East: Siemens AG Healthcare Sector Henkestraße 127 D-91052 Erlangen Germany Phone: +49 9131 84 - 0 www.siemens.com/healthcare Latin America: Siemens S.A. Medical Solutions Avenida de Pte. Julio A. Roca No 516, Piso 7 C1067ABN Buenos Aires Argentina Phone: +54 11 4340 - 8400 www.siemens.com/healthcare USA: Siemens Medical Solutions U.S.A., Inc. 51 Valley Stream Parkway Malvern, PA 19355-1406 USA Phone: +1-888-826 - 9702 www.siemens.com/healthcare Global Siemens Healthcare Headquarters Siemens AG Healthcare Sector Henkestraße 127 91052 Erlangen Germany Phone: +49 9131 84 - 0 www.siemens.com/healthcare Global Siemens Headquarters Siemens AG Wittelsbacherplatz 2 80333 Muenchen Germany Order No. A91CT-41011-97M1-7600 | Printed in Germany | CC CT 41011 ZS 1110/32. | © 11.2010, Siemens AG SUBSCRIBE NOW! – and get your free copy of future SOMATOM Sessions! Interesting information from the world of computed tomography – gratis to your desk. Send us this postcard, or subscribe online at www.siemens.com/ct-news SOMATOM Sessions Siemens AG Healthcare Sector H CC 11 Henkestraße 127 91052 Erlangen Germany