Computed Tomography Dose Index, Includes various CTDI parameters and the way of calculating effective dose from various Computed Tomography procedures along with their conversion factor.
MDCT Principles and Applications- Avinesh ShresthaAvinesh Shrestha
Multidetector CT (MDCT) is one of the most commonly used imaging modality in the field of Radiology. Development and advancement in MDCT has made it's application as a major component in diagnosis and treatment planning of multitude of disease across the planet. This presentation briefly describes its basic principle and it's wide variety of application in medical imaging.
Computed Tomography Dose Index, Includes various CTDI parameters and the way of calculating effective dose from various Computed Tomography procedures along with their conversion factor.
MDCT Principles and Applications- Avinesh ShresthaAvinesh Shrestha
Multidetector CT (MDCT) is one of the most commonly used imaging modality in the field of Radiology. Development and advancement in MDCT has made it's application as a major component in diagnosis and treatment planning of multitude of disease across the planet. This presentation briefly describes its basic principle and it's wide variety of application in medical imaging.
Application of dect in emergency radiology including the application in diagnosis of renal calculi, bone marrow edema, gout , abdominopelvic imaging,detection of pulmonary embolism and in cardiac imaging.
CT is one of the highest contributor for medical radiation exposure to patients. Some common CT dose descriptors and dose optimizations methods are briefly described in this presentation.
it includes generations and advancement in CT. In generations fifth generation CT is described in detail.
UFC detector, stellar detectors and gemstone detector is also described
straton x-ray tube, MRC, LIMAX and aquillion one xray tube
different techniques used in CT
dual energy CT is also described
Basic physics of multidetector computed tomography ( CT Scan) - how ct scan works, different generations of ct, how image is generated and displayed and image artifacts related to CT Scan.
Ultrasound elastography is a relatively advanced technique used to know the stiffness of the tissue. It is a non-invasive technique. Broadly classified into Quasistatic and Dynamic elastography.
Application of dect in emergency radiology including the application in diagnosis of renal calculi, bone marrow edema, gout , abdominopelvic imaging,detection of pulmonary embolism and in cardiac imaging.
CT is one of the highest contributor for medical radiation exposure to patients. Some common CT dose descriptors and dose optimizations methods are briefly described in this presentation.
it includes generations and advancement in CT. In generations fifth generation CT is described in detail.
UFC detector, stellar detectors and gemstone detector is also described
straton x-ray tube, MRC, LIMAX and aquillion one xray tube
different techniques used in CT
dual energy CT is also described
Basic physics of multidetector computed tomography ( CT Scan) - how ct scan works, different generations of ct, how image is generated and displayed and image artifacts related to CT Scan.
Ultrasound elastography is a relatively advanced technique used to know the stiffness of the tissue. It is a non-invasive technique. Broadly classified into Quasistatic and Dynamic elastography.
Computed tomography (CT scan) is a medical imaging procedure that uses computer-processed X-rays to produce tomographic images or 'slices' of specific areas of the body. These cross-sectional images are used for diagnostic and therapeutic purposes in various medical disciplines.
This is a presentation of a Quality Improvement Project conducted in King Faisal Specialist Hospital (KFSH&RC), CT section. Under the Course: Healthcare Quality Improvement, HSQM 614. king Saud bin Abdulaziz university for health sciences.
- Project Timeline: (5 October - 29 December) 2016.
- Project Leader: Bandar AlGhamdi
- Course Instructor: Dr. Khaled Al Surimi
Role of mdct in blunt abdominal trauma Dr. Muhammad Bin Zulfiqar
Briefly Describes the role of Ct in Diagnosis of Blunt Abdominal trauma.
Major organs injuries are discussed
Molecular imaging has revolutionized our perceptions of imaging. This high impact field is finding transformative applications in the understanding, detection, and treatment of nearly all diseases.
The field of molecular imaging is a an exciting fusion and integration of many different disciplines including molecular biology, chemistry and probe design, imaging technologies, visualization, and image analysis, that are focused on understanding, detecting, and treating oncological, neurological, cardiovascular, inflammatory, metabolic, and infectious diseases. Based on their strengths, different imaging modalities provide different but equally valuable information that can be integrated in advancing our understanding of these diseases.
As the era of ‘omics’ progresses towards personalized medicine, the field of molecular imaging is finding multiple uses in noninvasive characterization of the molecular features of diseases and their impact on function. In complex diseases such as cancer, with its tremendous genetic diversity, it is becoming increasingly important to develop molecularly-targeted treatment strategies that combine detection with treatment.
Overview of Integrated Detector Electronics products including Application Specific Integrated Circuits, ROICs and low noise amplifiers for radiation detection.
This talk delvers an hour-long overview of MR physics focusing on multiple topics at an introductory level, proceeds to provide tools that are open source based, for MR enthusiasts and beginners
Dual energy imaging and digital tomosynthesis: Innovative X-ray based imaging...Carestream
Dual-energy (DE) imaging and digital tomosynthesis (DT) have been around for a few decades, but recent advancements in digital detectors have made this technology increasingly promising in clinical use. For more information about Carestream's imaging portfolio, visit www.carestream.com/medical or http://www.carestream.com/blog/2016/03/15/dual-energy-imaging-and-digital-tomosynthesis/
Digital Breast Tomosynthesis with Minimal CompressionDavid Scaduto
Breast compression is utilized in mammography to improve image quality and reduce radiation dose. Lesion conspicuity is improved by reducing scatter effects on contrast and by reducing the superposition of tissue structures. However, patient discomfort due to breast compression has been cited as a potential cause of noncompliance with recommended screening practices. Further, compression may also occlude blood flow in the breast, complicating imaging with intravenous contrast agents and preventing accurate quantification of contrast enhancement and kinetics. Previous studies have investigated reducing breast compression in planar mammography and digital breast tomosynthesis (DBT), though this typically comes at the expense of degradation in image quality or increase in mean glandular dose (MGD). We propose to optimize the image acquisition technique for reduced compression in DBT without compromising image quality or increasing MGD. A zero-frequency signal-difference-to-noise ratio model is employed to investigate the relationship between tube potential, SDNR and MGD. Phantom and patient images are acquired on a prototype DBT system using the optimized imaging parameters and are assessed for image quality and lesion conspicuity. A preliminary assessment of patient motion during DBT with minimal compression is presented.
A summary of recent innovations in radiation oncology focussing on the priniciples of different techniques and their application. An overview of clinical results has also been given
“Alopecia-less” Whole Brain Radiotherapy: Preliminary Experience and OutcomesTodd Scarbrough
Whole brain radiotherapy (WBRT) is indicated for many patients with brain metastases. Most of these patients develop alopecia with standard WBRT technique (opposed lateral fields). A multi-field, very conformal beam arrangement might limit scalp dose thereby resulting in less or eliminated alopecia toxicity. We present our initial clinical experience with a new technique of WBRT, as well as limited comparative analyses of dosimetric data.
Similar to Dose reduction in MDCT . Daniel J.P , Khorfakhan hospital . UAE (20)
Model Attribute Check Company Auto PropertyCeline George
In Odoo, the multi-company feature allows you to manage multiple companies within a single Odoo database instance. Each company can have its own configurations while still sharing common resources such as products, customers, and suppliers.
We all have good and bad thoughts from time to time and situation to situation. We are bombarded daily with spiraling thoughts(both negative and positive) creating all-consuming feel , making us difficult to manage with associated suffering. Good thoughts are like our Mob Signal (Positive thought) amidst noise(negative thought) in the atmosphere. Negative thoughts like noise outweigh positive thoughts. These thoughts often create unwanted confusion, trouble, stress and frustration in our mind as well as chaos in our physical world. Negative thoughts are also known as “distorted thinking”.
This is a presentation by Dada Robert in a Your Skill Boost masterclass organised by the Excellence Foundation for South Sudan (EFSS) on Saturday, the 25th and Sunday, the 26th of May 2024.
He discussed the concept of quality improvement, emphasizing its applicability to various aspects of life, including personal, project, and program improvements. He defined quality as doing the right thing at the right time in the right way to achieve the best possible results and discussed the concept of the "gap" between what we know and what we do, and how this gap represents the areas we need to improve. He explained the scientific approach to quality improvement, which involves systematic performance analysis, testing and learning, and implementing change ideas. He also highlighted the importance of client focus and a team approach to quality improvement.
How to Create Map Views in the Odoo 17 ERPCeline George
The map views are useful for providing a geographical representation of data. They allow users to visualize and analyze the data in a more intuitive manner.
Operation “Blue Star” is the only event in the history of Independent India where the state went into war with its own people. Even after about 40 years it is not clear if it was culmination of states anger over people of the region, a political game of power or start of dictatorial chapter in the democratic setup.
The people of Punjab felt alienated from main stream due to denial of their just demands during a long democratic struggle since independence. As it happen all over the word, it led to militant struggle with great loss of lives of military, police and civilian personnel. Killing of Indira Gandhi and massacre of innocent Sikhs in Delhi and other India cities was also associated with this movement.
Palestine last event orientationfvgnh .pptxRaedMohamed3
An EFL lesson about the current events in Palestine. It is intended to be for intermediate students who wish to increase their listening skills through a short lesson in power point.
Synthetic Fiber Construction in lab .pptxPavel ( NSTU)
Synthetic fiber production is a fascinating and complex field that blends chemistry, engineering, and environmental science. By understanding these aspects, students can gain a comprehensive view of synthetic fiber production, its impact on society and the environment, and the potential for future innovations. Synthetic fibers play a crucial role in modern society, impacting various aspects of daily life, industry, and the environment. ynthetic fibers are integral to modern life, offering a range of benefits from cost-effectiveness and versatility to innovative applications and performance characteristics. While they pose environmental challenges, ongoing research and development aim to create more sustainable and eco-friendly alternatives. Understanding the importance of synthetic fibers helps in appreciating their role in the economy, industry, and daily life, while also emphasizing the need for sustainable practices and innovation.
How to Split Bills in the Odoo 17 POS ModuleCeline George
Bills have a main role in point of sale procedure. It will help to track sales, handling payments and giving receipts to customers. Bill splitting also has an important role in POS. For example, If some friends come together for dinner and if they want to divide the bill then it is possible by POS bill splitting. This slide will show how to split bills in odoo 17 POS.
4. DOSE REDUCTION IN MDCT
Progress of technology
Generation X-ray beam Detector Motion
1 generation Pencil beam Single
detector
Linear and
rotary
(translate
rotate
2 generation Fan beam Multiple
detector
As above
3 generation Fan beam Multiple
detector
Rotary
motion only
4 generation Fan beam Multiple
detector
Only tube
moves in a
circle
5 generation Electron
beam CT
6 generation Spiral CT
7 generation Multi
detector
Array of
detectors
5. DOSE REDUCTION IN MDCT
Outline
Reasons for increased dose in MDCT.
Dose optimization techniques
Dose Reference Levels
CT dose units
Effective dose units
Bismuth shielding
Summary
6. DOSE REDUCTION IN MDCT
Algorithm for image reconstruction
1. Back projection
2. Iterative method
3. Analytical method
(a)2D fourier analysis
(b) Filtered back projection
4. ASIR – adaptive statistical iterative reconstruction
7. DOSE REDUCTION IN MDCT
CT image acquisition
Intensity profile- measurement of attenuation
values at detector
Each projection is an intensity profile
1000 projection for 1 slice
Each projection has 704 variables sample
70,000 samples for each slice
8. DOSE REDUCTION IN MDCT
(contd)
Pre-processing – intensity profile are converted into an electronic format
Any errors due to physical or technical reasons are corrected
Back projection- the intensity profile are stretched corresponding to the
direction from which the profile was measured at the detector array
Convolution – the back projection images are blurred and these are
corrected by mathematical procedure
Filtered Back Projection– data further filtered and any profile responsible
for blurring is filtered
algorithms – smooth , standard , sharp
ASIR-Adaptive statistical iterative reconstruction
9. DOSE REDUCTION IN MDCT
Pitch in SSCT = table travel/slice thickness
Pitch in MSCT= table travel/sum of active detectors
Contrast resolution – ability of the system to detect a single
structure that varies slightly from the surrounding.
Spatial resolution – ability of system to distinguish two small
adjacent objects.
Noise-portion of signal which contains no information.
Linearity –ability of the system to display accurate
attenuation values.
10. DOSE REDUCTION IN MDCT
Are doses in MDCT different and why ?
•Scan Volume
•Shorter source to pt distance
•Increase in MAS to over come graininess in thin slices
•larger pt volume
•Multiple contrast phases
•Over lapping scans
•Over beaming and over ranging.
•Pitch
11. DOSE REDUCTION IN MDCT
Dose optimisation techniques
• Tube current modulation(X,Y,Z)
• AEC
• Table speed(cm/s)
• Gantry rotation time
• KVp
• Minimizing contrast phases
12. DOSE REDUCTION IN MDCT
Tube current modulation(angular X & Y , longitudinal Z)
Adjust the tube current according to pt size and pt
anatomy
Reduce d dose with consistent image quality
Dose reduction by 10 to 5o%
AEC
Scanogram suggests required MAS according to pt size
Dose reduction from 20 to 44%
14. DOSE REDUCTION IN MDCT
(cotd)
Table speed(cm/s)- inversely propotional to dose
(halving the table speed doubles the exposure).
Gantry rotation time – directly propotional to
exposure(doubling the gantry time doubles the
exposure)
KVp – reducing tube potential reduces dose but
increases grains(90 to 120KVp)
Contrast studies should be phase specific
15. DOSE REDUCTION IN MDCT
Paediatric imaging - diagnostic quality not
optimum quality
Reduce MAS , FOV , KVp(80 to 100KVp)
Shorter tube rotation time
16. DOSE REDUCTION IN MDCT
Dose reference levels
Reference level appropriate for average sized patient,age
,clinical data and region of imaging.
Advantage
•Compare CT dose with other modality
•Compare practise with other centers
•Realize if we have certain margin of optimization
•Detect abnormal situation where dose limits are
increased
17. DOSE REDUCTION IN MDCT
DRL
Why do we need DRLs?
•Optimization
•Protocols tailored
•Promote and develop current protocol
•NDRLs and LDRLs - awareness , audit and comparing
25. DOSE REDUCTION IN MDCT
Bismuth shielding
1. Reduces dose to skin and superficial organs
2. Reduces primary beam attenuation
3. In thoracic scans reduces breast dose by 43 –
70 % (In practise female <50 years)
4. Attenurad bismuth shield 0.06mm Pb covered
with plastic
5. Shield placement - tip of the shield on sternal
notch and cover around axilla (after scout)
6. Other application if compatible use for
thyroid and eye
26. DOSE REDUCTION IN MDCT
1. Gonadal shield in abdomen reduces dose
from 2.4 – 0.32 mSv
2. In CTA prospectively 35 – 40%
3. In CT urograph reduction in kV reduces dose
by 7 – 2.9 mSv
4. X, Y &Z axis current modulation reduces dose
in colonography
5. Paediatric image of diagnostic quality not
optimum quality (reduced mAs ,FOV ,kV
between 80 - 100 ,shorter rotation time )
6. Low contrast volume and low KV in renal
dysfunction
27. DOSE REDUCTION IN MDCT
Images in a 70-year-old
woman show normal brain.
Standard- and low-dose
nonenhanced head CT scans
at identical levels are
compared.
A and B, Posterior fossa
(medulla and cerebellar
hemispheres) at 170 (A) and
90 (B) mAs.
C and D, Thalamus (deep GM)
and forceps major (WM) at
170 (C) and 90 (D) mAs.
E and F, Centrum semiovale
(WM) at 170 (A) and 90 (B)
mAs
28. DOSE REDUCTION IN MDCT
58-year-old man with body mass
index (kg/m2) of 26.5. Images in
both panels matched same level
of
liver, which includes main portal
vein and medial edge of posterior
liver.
A, Representative low-dose CT
image with adaptive statistical
iterative reconstruction (volume
CT dose index
[CTDIvol], 9 mGy; 120 kV; 3.75
mm slice thickness) is shown.
Note decreased sharpness of
aortic wall.
B, Representative routine-dose CT
image with filtered back
projection (CTDIvol, 18 mGy; 120
kVp; 3.75 mm slice
29. DOSE REDUCTION IN MDCT
Transverse CT scans obtained at
different milliampere-second settings
show mass on lower lobe of right lung
on 74-year-old man. Both scans were
rated as normal-quality images.
Transverse CT scans were obtained at
115 mAs (150 mA) (A) and 25 mAs (30
mA) (B).
Transverse CT scans obtained at different
milliampere-second settings show mass on
lower lobe of right lung on 74-year-old man.
Both scans were rated as normal-quality
images. Transverse CT scans were obtained at
115 mAs (150 mA) (A) and 25 mAs (30 mA) (B).
30. DOSE REDUCTION IN
MDCT
75-year-old man with body
mass index of 22. Low-dose
CT scans without (A) and with
(B) adaptive statistical
iterative reconstruction (120
kVp; 3.75-mm slice thickness;
CT dose index [CTDI], 11) and
routine-dose CT scan (C) (140
kVp; 3-mm slice thickness;
CTDI, 20) all show hepatic
cysts, but sharpness of cyst
edges is best in C. B has least
image noise.
31. DOSE REDUCTION IN MDCT
Take home points:
1. Know your CT dose units
2. Audit CT doses
3. Archive dose reports
4. Think about possible site related DRL”s
5. Review dose technique
6. Use dose modulation whenever possible
7. Use shielding if available
8. Ask Radiologist to accept images with noise.
9. Empower Technologist to adjust protocols
10. ASIR .
11. Decision support software
12. Think of alternate modalities.
13. Provision of patient information material.
14. Always keep ALARA in mind!
32. PROGRESS…
CT doses 1/3 lower than a
decade ago
Expect 10-fold+ or more
reduction in next few
years
ACR National Dose
Registry-collect data on all
CT exams
