Somatom Sessions 26 - SIEMENS


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Somatom Sessions 26 - SIEMENS

  1. 1. Global Siemens Headquarters Global Siemens SOMATOM Sessions SOMATOM Sessions Rapid evaluation is Healthcare Headquarters Siemens AG critical after trauma and Wittelsbacherplatz 2 Siemens AG with symptoms such as 80333 Muenchen Healthcare Sector weakness, headache, Germany Henkestraße 127 and dizziness, which is why CT is the modality 91052 Erlangen Germany The Difference in Computed Tomography of choice in these Phone: +49 9131 84 - 0 scenarios. Exceptional image quality is key to optimize diagnosis, and lower dose imaging Issue Number 26 / May 2010 ISCT- / ASNR-Edition I May 18th – May 21st, 2010 26 minimizes risk to the patient. Order No. A91CT-41011-14M1-4A00 | Printed in Germany | CC CT 41011 ZS 0510/8. | © 05.2010, Siemens AG May 2010 Cover Story On account of certain regional limitations of Global Business Unit Local Contact InformationSUBS CRIBE NOW! sales rights and service availability, we cannot The Best of Both Worlds guarantee that all products included in this Siemens AG Asia/Pacific: in Neuro Imaging– and get your free copy of future brochure are available through the Siemens Medical Solutions Siemens Medical Solutions Page 6SOMATOM Sessions! Interesting information sales organization worldwide. Availability and Computed Tomography Asia Pacific Headquarters packaging may vary by country and is subject Siemensstraße 1 The Siemens Centerfrom the world of computed tomography – gratis to change without prior notice. Some/All of the features and products described herein may 91301 Forchheim Germany 60 MacPherson Road Singapore 348615 Newsto your desk. Send us this postcard, or subscribe not be available in the United States. Phone: +49 9191 18 - 0 Phone: +65 9622 - 2026 Best Balance Betweenonline at Image Quality The information in this document contains general technical descriptions of specifications Canada: and Reduced Dose and options as well as standard and optional Siemens Canada Limited Page 18 features which do not always have to be present Medical Solutions in individual cases. 2185 Derry Road West Mississauga ON L5N 7A6 Business Siemens reserves the right to modify the design, Canada packaging, specifications and options described Phone: +1 905 819 - 5800 New Feature: Neuro herein without prior notice. Image Quality Surpasses Please contact your local Siemens sales representative for the most current information. Europe/Africa/Middle East: all Expectations Siemens AG Page 26 ISCT-Edition Note: Any technical data contained in this Medical Solutions document may vary within defined tolerances. Original images always lose a certain amount Henkestraße 127 D-91052 Erlangen Clinical of detail when reproduced. Germany Results Henkestraße 127 Halthcare Sector 91052 Erlangen Phone: +49 9131 84 - 0 SOMATOM Definition AS+: Siemens AG CT Perfusion With Germany Latin America: H CC 11 Siemens S.A. Extended Coverage for Medical Solutions Acute Ischemic Stroke Avenida de Pte. Julio A. Roca No 516, Piso 7 C1067ABN Buenos Aires Argentina Page 46 Phone: +54 11 4340 - 8400 Science USA: CT in Pediatrics: Easier Siemens Medical Solutions U.S.A., Inc. and Safer With the FlashSOMATOM 51 Valley Stream Parkway Malvern, PA 19355-1406 Page 58 USASessions Phone: +1-888-826 - 9702
  2. 2. Editorial Imprint “Neuro BestContrast SOMATOM Sessions – IMPRINT © 2010 by Siemens AG, Berlin and Munich A. Becker, MD, Department of Clinical Radiology, University of Munich, Campus Großhadern, F. Schoth, MD, RWTH Aachen University Hospital, Aachen, Germany allows radiologists to All Rights Reserved Munich, Germany C. R. Becker, MD, Department of Clinical Radiology, F. Schwarz, MD, Department of Clinical Radiology, University of Munich, Campus Großhadern, better visualize subtle Publisher: Siemens AG Healthcare Sector University of Munich, Campus Großhadern, Munich, Germany Munich, Germany H. Seifarth, MD, Department of Clinical Radiology, edemas as well as Business Unit Computed Tomography Siemensstraße 1, 91301 Forchheim, Germany G. Feuchtner, MD, Institute of Diagnostic Radiolo- gy, University Hospital Zurich, Zurich, Switzerland University Hospital, Münster, Germany K. Takada, MD, Department of Radiology, subtle signs of stroke, Chief Editors: M. Fischer, MD, Institute of Diagnostic Radiology, Sakakibara Heart Institute, Tokyo, Japan and to better delineate “Our new neurological University Hospital Zurich, Zurich, Switzerland T. J. Vogl, MD, Department of Diagnostic and R. Goetti, MD, Institute of Diagnostic Radiology, University Hospital Zurich, Zurich, Switzerland Interventional Radiology, Clinic of the Goethe Uni- versity, Frankfurt, Germany the cortical margin.” W. Heindel, MD, Department of Clinical Radiology, P. Weisser, MD, Department of Diagnostic and In- software combined with University Hospital, Münster, Germany terventional Radiology, Clinic of the Goethe University, Frankfurt, Germany David S. Enterline, MD, J. M. Kerl, MD, Department of Diagnostic and Duke University Medical Center in Durham, North Carolina, USA Interventional Radiology, Clinic of the Goethe M. Wieser, MD, Clinic of Cardiovascular Surgery, University, Frankfurt, Germany University Hospital Zurich, Zurich, Switzerland the SOMATOM Definition M. Lell, MD, Department of Radiology and C. Wyss, MD, Cardiology Division, University Monika Demuth, PhD Stefan Wünsch, PhD the Imaging Science Institute (ISI), University Hospital Zurich, Zurich, Switzerland (monika.demuth@ (stefan.wuensch@ of Erlangen-Nuremberg, Erlangen, Germany Sameh Fahmy, freelance medical and technology S. Leschka, MD, Institute of Diagnostic Radiology, journalist Tony DeLisa, freelance author University Hospital Zurich, Zurich, Switzerland Wiebke Kathmann, PhD, freelance scientific journalist line of scanners repre- Responsible for Contents: André Hartung Hildegard Kaulen, PhD, freelance scientific journalist K. Lin, MD, Department of Radiology, New York Oliver Klaffke, freelance scientific journalist Editorial Board: University Langone Medical Center, New York, Annette Tuffs, MD, medical journalist Andreas Blaha NY, USA Helge Bohn Peter Aulbach; Karin Barthel; Andreas Blaha; A. H. Mahnken, MD, RWTH Aachen University sents a quantum leap Andreas Fischer Steven Bell; Ivo Driesser; Kerstin Fellenzer; Tomoko Hospital, Aachen, Germany Thomas Flohr, PhD Fujihara; Jan Freund; Tanja Gassert; Toshihide Julia Hoelscher Y. Mizutani, MD, Department of Radiology, Itoh; Christiane Koch, Rami Kusama; Marion Klaudija Ivkovic Sakakibara Heart Institute, Tokyo, Japan Meusel; Jakub Mochon; Katharina Otani, PhD; Axel Lorz Kerstin Putzer; Heike Theessen; Peter Seitz; Ste- K. Nikolaou, MD, Department of Clinical Radiology, Please enter your business address in speed, low dose and fan Ulzheimer PhD; Fernando Vega-Higuera; Country State City Postal Code Street Name Title Function Department Institution Peter Seitz University of Munich, Campus Großhadern, Stefan Ulzheimer, PhD Stefan Wünsch, PhD; all Siemens Healthcare Munich, Germany Alexander Zimmermann Photo Credits: Greg Morris, Yohanne Lamoulére/ J.-F. Paul, MD, Centre Chirurgical Marie Authors of this Issue Agentur Focus, Harald Krieg, Thorsten Rother Lannelongue, Le Plessis-Robinson, France H. Alkadhi, MD, Institute of Diagnostic Radiology, diagnostic accuracy.” Production: Norbert Moser, Siemens AG, University Hospital Zurich, Zurich, Switzerland A. Plass, MD, Clinic of Cardiovascular Surgery, Medical Solutions University Hospital Zurich, Zurich, Switzerland F. Bamberg, MD, Department of Clinical Radiology, Design and Editorial Consulting: University of Munich, Campus Großhadern, B. Policeni, MD, Radiology Faculty, Neuroradiology, Independent Medien-Design, Munich, Germany Munich, Germany University of Iowa Hospitals and Clinics, Iowa In cooperation with Primafila AG, Zurich, City, Iowa, USA R. W. Bauer, MD, Department of Diagnostic and Switzerland; Interventional Radiology, Clinic of the Goethe H. Scheffel, MD, Institute of Diagnostic Radiology, Managing Editor: Christa Löberbauer; University, Frankfurt, Germany University Hospital Zurich, Zurich, Switzerland Photo Editor: Susanne Nips; Layout: Claudia Diem, Mathias Frisch; All at: Widenmayerstraße 16, 80538 Munich, Germany SOMATOM Sessions is also available on the internet: Subscription Sami Atiya, PhD, Chief Executive Officer, Business Unit Computed Tomography, Siemens Healthcare, Forchheim, Germany Note in accordance with § 33 Para.1 of the German Federal Data Protection Law: The drugs and doses mentioned herein are consistent with the approval labeling Despatch is made using an address file which is maintained with the aid of an for uses and/or indications of the drug. 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We welcome your questions and comments about the editorial content of The information presented in these articles and case reports is for illustration only SOMATOM Sessions. Manuscripts as well as suggestions, proposals and informa- and is not intended to be relied upon by the reader for instruction as to the prac- tion are always welcome; they are carefully examined and submitted to the edito- Cover Page: With Volume Perfusion CT Neuro fused with carotid CT Angiography the perfusion status of the brain tissue tice of medicine. Any health care practitioner reading this information is remind- rial board for attention. SOMATOM Sessions is not responsible for loss, damage, can be observed. Courtesy of University Hospital Göttingen, Germany. ed that they must use their own learning, training and expertise in dealing with or any other injury to unsolicited manuscripts or other materials. We reserve the their individual patients. This material does not substitute for that duty and is not right to edit for clarity, accuracy, and space. Include your name, address, and intended by Siemens Medical Solutions to be used for any purpose in that regard. phone number and send to the editors, address above.2 SOMATOM Sessions · May 2010 · SOMATOM Sessions · May 2010 · 73 Please print clearly!
  3. 3. Editorial André Hartung, Vice President Marketing and Sales Business Unit CT, Siemens HealthcareDear Reader,Imagine an emergency room only a With syngo.via, Siemens’ new work- sure. CT is steadily moving into the firstfew short years ago: in the middle of place software, all time consuming line of emergency and stroke imagingthe night, a 55-year-old, unconscious pre- and post-processing steps are mainly because of the wide diagnosticpatient is wheeled in. All neurologic eliminated and all diagnostic infor- spectrum, speed and diagnostic pre-observations indicate stroke. But mation – including information from cision. Providing all the advantages inhow severe? Is it an occlusion or a other modalities such as MR, MI and CT imaging aligned with measures tohemorrhage and where is it located? PET – are available in almost real time. minimize the radiation exposure hasAll crucial questions that demand fast Best possible image quality is pro- always been one of Siemens key goals.answers! The physician on duty could vided with sophisticated “signal boost” Therefore we have recently introducedrequest a head CT examination that technologies or image-optimizing new technical developments like IRIS tocould possibly involve two scans at 15 techniques resulting in definitive reduce radiation exposure to the lowestto 30 mSv radiation dose. The physician grey and white tissue differentiation level in the CT industry. In functionalwould then begin with extensive post- in neuro imaging. Excellent image imaging, e.g. for CT brain perfusion, theprocessing – possibly using a PACS quality and fast processes are bene- dose can be reduced by up to 50 % withWorkstation before the CT results could ficial for both physicians and patients 4D Noise Reduction, without compro-provide life the necessary clinical infor- as they are preconditions for highest mising image quality. And our Adaptivemation required. Not a very pleasant diagnostic accuracy and, at the same Dose Shield completely eliminates pre-alternative for the physicians or the time, low dose safety for the patient. and post-spiral radiation that cannot bepatient. utilized for image reconstruction. These In all patient groups, including difficult are only a few examples from dozens ofNow imagine the same situation in a obese and pediatric patients, as well as additional large and small improvementsmodern emergency room equipped with emergency room situations, safety is developed by our dedicated employeesSiemens cutting-edge technology such strongly linked to ALARA (As Low As to make the radiologist’s life easier andas SOMATOM Definition Flash scanner – Reasonably Achievable) radiation ex- the patient’s healthcare better. You willthat scans faster than all other CT posure. In the past, especially in acute find many of these reported in this, andscanners on the market – with latest clinical cases, lowering the radiation in future editions of SOMATOM Sessions.neuro imaging software and syngo.via exposure when utilizing CT for diagnosissoftware that “post-process on-the-fly” was not the primary focus. In stroke Good reading,Within minutes, the physician would cases, “minutes equaled mind” and for Sincerelyhave access to the head scan results with accident victims, minutes could meanall post-processing completed at lowest life or death. Today, thanks to Siemens’possible dose, including non-enhanced significant leadership in bringing lowCT for exclusion of hemorrhage, com- dose CT into clinical routine, image André Hartungplete vascular status plus functional quality is not necessarily tied to a slowerinformation. diagnosis path and higher dose expo-* 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.. SOMATOM Sessions · May 2010 · 3
  4. 4. Content 6 22 Content The Best of Both Worlds International CT Image Contest at Lowest DoseCover Story Cover Story 6 Exciting advances in computed 6 The Best of Both Worlds in Neuro tomography (CT) examination Imaging methods, including low dose protocols, technical innovations such as whole brain CT Perfusion, News Dual Energy or Neuro Best Contrast applications and groundbreaking 16 Affordable Performance in 16- and radiological research have drama- 64-slice CT tically changed the diagnostic 18 Best Balance Between Image Quality approach for reading physicians and Reduced Dose by enabling new indications and 19 IRIS Now Extended to SOMATOM improved timing in the examination Definition AS 20 and SOMATOM of patients with acute neurological Definition AS 40 deseases. SOMATOM Sessions 20 syngo CT 2010B Now Available: discussed with five experienced New Software Version for the physicians how CT can routinely be SOMATOM Definition AS Launched used as the key diagnostic modality 21 Worldwide Dose Counter in neuro imaging before the start 22 International CT Image Contest – of appropriate treatment. Highest Image Quality at Lowest Dose4 SOMATOM Sessions · May 2010 ·
  5. 5. Content 48 60– Highest Image Quality Vasospasm After Subarachnoid Hemorrhage: Study Finds Atherosclerosis in 3,500 Volume Perfusion CT Neuro Year old Egyptian Mummies Business Science 26 New Feature: Neuro Image Quality Oncology 58 CT in Pediatrics: Easier and Safer Surpasses all Expectations 42 3D Guided RF Ablation and CT With the Flash Perfusion – a New Combination for 60 Study Finds Atherosclerosis in Monitoring of Treatment Response 3,500 Year old Egyptian Mummies Clinical Results 44 SOMATOM Definition Flash: 61 Independent Validation of Perfusion Routine Re-staging of Oesophageal Evaluation Software Cardio-Vascular Carcinoma Utilizing IRIS Technology 62 Reduced Procedure Time and 28 Adenosine Myocardial Stress Radiation Dose in Interventional Imaging Using SOMATOM Neurology CT Workflow Definition Flash 46 SOMATOM Definition AS+: CT 64 Scientific Validation of the 30 SOMATOM Definition Flash: Perfusion With Extended Coverage SOMATOM Definition Flash Visualization of the Adamkiewicz for Acute Ischemic Stroke Artery by IV-CTA in Dual Power Mode 48 Vasospasm After Subarachnoid 32 Dynamic Myocardial Stress Perfusion Hemorrhage: Volume Perfusion CT Life 34 Pre-operative Exclusion of Coronary Neuro Artery Stenosis With Less Than 66 Behind the Scenes: CT Scan Protocols 1 mSv Dose Acute Care 68 First syngo.via Hands-on Workshops 36 Utilizing Ultra Low Dose of 0.05 mSv 52 Dual Energy Scanning: Diagnosis at ECR 2010 for Premature Baby With Congenital of Ruptured Cocaine Capsule 68 Upcoming Events & Congresses Heart Disease 54 Progressive Kidney Hematoma 69 Training Website for Knowledge 38 SOMATOM Definition Flash: Pediatric Post-interventional Biopsy Improvement Patient Without Sedation and 56 SOMATOM Definition Dual Source 69 Free Trial Licenses for Neuro Imaging Breath-Holding High Pitch vs. Routine Pitch Scanning 70 Frequently Asked Questions 40 SOMATOM Definition Flash: Dual in a Pediatric Lung Low Dose 70 Dual Energy CT: Learning From the Energy Coronary CT Angiography for Examination Experts Evaluation of Chest Pain After RCA 71 Clinical Workshops 2010 Revascularization 72 Siemens Healthcare – Customer Magazines 73 Imprint SOMATOM Sessions · May 2010 · 5
  6. 6. Coverstory6 SOMATOM Sessions · May 2010 ·
  7. 7. CoverstoryThe Best of Both Worlds inNeuro ImagingExceptional Image Quality Meets Lowest Dosein NeuroradiologyAt Duke University Medical Center in Durham, North Carolina, USA andelsewhere, Siemens equipment is helping radiologists combine exceptionalimage quality in neuro imaging with innovative dose-reducing featuresto maximize diagnostic confidence.By Sameh FahmyExciting advances in computed tomo- Perfusion imaging with Siemens’ uniquegraphy (CT) examination methods, in- Adaptive 4D Spiral and the use of CTcluding low dose protocols, technical Angiography from the aortic arch to theinnovations such as whole brain CT cranium are further expanding possibili-Perfusion, Neuro BestContrast or Dual ties, increasing the diagnostic confidenceEnergy applications and groundbreaking of neurologists and potentially enablingradiological research have dramatically more appropriate treatment decisions.changed the diagnostic approach for “By providing really good image quality,reading physicians by enabling new indi- we are able to improve the efficiency ofcations and improved timing in the ex- care,” says David S. Enterline, MD, Asso-amination of patients with acute neuro- ciate Professor of Radiology and Divisionlogical deseases. CT is routinely used as Chief of Neuroradiology at Duke Uni-the key diagnostic modality in neuro versity Medical Center in Durham, Northimaging before the start of appropriate Carolina, USA. “And through dose sav-treatment to detect or exclude intracra- ings, we can minimize the risk to pa-nial hemorrhage, either traumatic or tients.” “Neuro BestContrastnon-traumatic, or to detect other causes allows radiologistsof acute onset of neurological disease, Neuro BestContrastsuch as stroke, intracerebral tumors, or Although newer techniques are revolu- to better visualizehematoma. Rapid evaluation is critical tionizing stroke assessment, the gold the gray/white mat-after trauma and with symptoms such standard for the initial diagnosis ofas weakness, headache, and dizziness, stroke and intracranial hemorrhage is ter interface to seewhich is why CT is the modality of still non-contrast imaging of the brain.choice in these scenarios. Siemens has always placed emphasis on subtle edema andExceptional image quality is key to opti- providing the highest image quality on signs of stroke, andmize diagnosis, and lower dose imaging all of their scanners for this challenginghelps to minimize the risk to the patient. application. Now, Siemens has taken to better delineateIt is often said that the price of improved image quality to the next level. Last the cortical margin.”image quality with CT is increased radia- year, Duke became the first hospital intion dose, but Siemens has shown that the United States to install Siemens’ David S. Enterline, MD, Division Chief Neuroradiology, Duke University Medicalhigh quality, low dose imaging is possi- Neuro BestContrast, an application that Center in Durham, North Carolina, USAble in even the most challenging neuro- dramatically increases gray/white matterradiology applications. Whole brain CT differentiation in non-contrast head CT SOMATOM Sessions · May 2010 · 7
  8. 8. Coverstory1A 1B 1C 1 Comparing conventional head CT imaging (Fig. 1A) with the new IRIS technology (Fig. 1B) shows decreased image noise. Combining IRIS with Neuro BestContrast technology provides very high image quality with decreased noise by utilizing reduced radiation dose (Fig. 1C).exams using the SOMATOM Definition experience of radiologists in Europe. In At the University Hospital in Göttingen,line of scanners. Enterline says that Neuro a blinded study whose results were pre- Germany, Peter Schramm, MD, DeputyBestContrast allows radiologists to sented at the 2009 scientific assembly Head of the Department of Neuro-better visualize subtle edemas as well and annual meeting of the Radiological radiology, was able to compare imagesas subtle signs of stroke, and to better Society of North America, neuroradiolo- acquired before and after the implemen-delineate the cortical margin, adding, gists preferred Neuro BestContrast data tation of Neuro BestContrast in a patient“My colleagues and I uniformly feel that sets in 97 % of cases.1 Other readers, with head trauma whose hospitalizationwith better image quality, our comfort who viewed the Neuro BestContrast coincided with the hospital’s transitionlevel and our ability to make diagnoses data set side-by-side with the traditional to the new software. “We were able toare significantly increased.” images, also rated image quality better perform an exact comparison intra-The improved image quality experienced in more than 90 % of the cases and individually, and in that case it was reallyby Enterline and his colleagues at Duke lesion conspicuity higher in more than impressive to see the improvement thatis also evidenced by clinical data and the 50 % of the cases. came along with Neuro BestContrast,” “I think Neuro BestContrast and IRIS work perfectly with each other and have additive value in reducing dose.” Christoph Becker, MD, Professor of Radiology and Section Chief of CT and PET/CT at Munich University Hospital, Munich, Germany8 SOMATOM Sessions · May 2010 ·
  9. 9. CoverstorySchramm says. “The delineation of the 2edema and the margins of the edema Iterative Reconstruction in Image Space (IRIS)were definitely better visualized usingNeuro BestContrast, and the same ap-plies to the changes that occur in acutestroke.”Neuro BestContrast improves non-con-trast head images by taking advantage Fast Image Data Spaceof the fact that clinically important infor-mation from CT scans is contained in me-dium and low frequencies, while high fre-quencies are dominated by image noise.The software processes high-frequency Image data Imagedata differently than the low-to-medium recon correctionfrequency data, resulting in improvedtissue contrast without the amplificationof image noise. CompareEnterline says the use of Neuro BestCon-trast has the potential to reduce radiationdose as well. His preliminary data hasdocumented a 15 to 20 % improvement Masterin gray/white matter differentiation that Slow Raw Data Space reconcan allow for image acquisition at a lowerdose than is currently used. “Our institu-tion has traditionally fought for lowerdose,” he says, “and I think this will nowallow us to further reduce our dose.”IRISNeuro BestContrast can be combinedwith another new Siemens technologyknown as Iterative Reconstruction in Strong artifact and dose reductionImage Space (IRIS) to reduce dose and Well-established image impressionimprove image quality even further. Fast reconstruction in image space“I think they work perfectly with eachother and have additive value,” says 2 IRIS takes all of the data, which contains fine details as well as significant amountsChristoph Becker, MD, Professor of Radi- of noise, combines it in a master image and cleans it up in the fast-processing image spaceology and Section Chief of Computed rather than in the slow-processing raw data area. The result is that that high spatial resolu-Tomography and PET/CT at Ludwig-Maxi- tion is preserved and noise is reduced – without disrupting workflow.milians-University in Munich, Germany.Iterative reconstruction uses a correctionloop to improve image quality in severalsteps, or iterations. The idea was first bines it in a master image and cleans it of dense structures such as bone andintroduced in the 1970s, but the com- up in the fast-processing image space calcium, making it easier to visualizeputing power and time required for the rather than in the slow-processing raw or rule out subarachnoid hemorrhage.reconstruction made it impractical for data area. The result is that high spatial Preliminary data from Becker show thatuse in clinical settings. An alternative resolution is preserved and noise is re- IRIS reduces dose by 25 % in head CTknown as statistical image reconstruction duced – without disrupting workflow. exams yet achieves the same level ofreduced the time associated with itera- Becker says the combination of Neuro noise as filtered back projection, the tra-tive reconstruction but produced a tex- BestContrast and IRIS, which is available ditional method for image reconstruc-ture that radiologists found unaccept- on the SOMATOM Definition line of tion. Becker notes that clinicians canable. With IRIS, Siemens took a different scanners, allows him and his colleagues also choose to use the same dose as fil-approach. The algorithm takes all of the to better differentiate the basal ganglia tered back projection yet deliver signifi-data, which contains fine details as well and to see subtle signs of stroke. He cantly better image quality using significant amounts of noise, com- adds that IRIS also reduces the blooming In the United States, Ridgeview Medical SOMATOM Sessions · May 2010 · 9
  10. 10. CoverstoryCenter in Waconia, Minnesota, USA in- CT while the patient is still in the scanner,stalled IRIS on its SOMATOM Definition allows improved detection of acuteAS 40-slice CT and its Definition AS+ stroke, which has been substantiated in128-slice scanner early in 2010. Chief several studies,” says Ke Lin, MD, Assis-of Radiology, David Gross, MD, directly tant Professor of Radiology at New Yorkcompared images produced using IRIS University Langone Medical Center inwith traditional filtered back projection New York City, USA. In a study of 100images and then enthusiastically adopt- patients presenting to the emergencyed IRIS. “After two or three days, we department within three hours of strokedecided that there’s no sense in even onset, Lin and his colleagues found thatcomparing anymore,” Gross says. “With CT Perfusion provided significantly im-the improvement in radiation dose, the proved sensitivity and accuracy in acuteimage quality is not changed, so we stroke detection over non-contrast CT.just switched right over to it.” Specifically, the researchers found thatNeuro BestContrast and IRIS build upon “With the improve- CT Perfusion revealed 64.6% of acuteother Siemens innovations in neuro infarctions compared to 26.2 % for non-imaging that maximize diagnostic confi- ment in radiation contrast CT. CT Perfusion also had an ac-dence. The “Posterior Fossa Optimization” dose using IRIS, curacy of 76 % compared to an accuracyalgorithm, which was introduced in 2001 of 52 % for non-contrast CT.2and is implemented in all SOMATOM the image quality Lin and his colleagues obtained CT Per-Sensation and Definition scanners, is not changed, so fusion data from a z-direction coveragesignificantly reduces streaks and dark of 24 mm centered at the mid-basalbands, known as Hounsfield Bars, to we just switched ganglia which maximizes the visualiza-allow for better resolution with less right over to it.” tion of the middle cerebral artery terri-artifact. Siemens’ z-Sharp Technology tory. Still, the researchers noted thatprovides routine isotropic resolution of David Gross, MD, Chief of Radiology they missed ten infarcts that were out-0.33 mm, one of the industry’s highest, Ridgeview Medical Center, Waconia, side of this volume of coverage. The ad-enabling the visualization of small Minnesota, USA vent of whole brain CT Perfusion usinganatomical details such as fine vascular Siemens’ unique Adaptive 4D Spiral, how-structures. For ultra-high-resolution bone ever, further increases the value of CTimaging for inner ear structures, Siemens’ Perfusion by expanding the scan range.z-UHR Technology provides 0.24 isotro- The revolutionary scan mode, which ispic resolution. hemorrhage and ischemic stroke mimics, available on the SOMATOM Definition the use of perfusion CT imaging is in- line of scanners, overcomes the limita-Perfusion CT and CTA creasingly being adopted. “Dynamic CT tions of a static detector design by ap-While non-contrast head CT exams are Perfusion imaging, which can be acquired plying a continuously repeated bi-direc-still important for excluding intracranial immediately after the non-contrast head tional table movement that smoothly “Dynamic CT Perfusion imaging, which can be acquired immediately after the non- contrast head CT while the patient is still in the scanner, allows improved detection of acute stroke, which has been substantiated in several studies.”2, 4 Ke Lin, MD, Assistant Professor of Radiology, Department of Radiology, New York University Langone Medical Center, New York, USA10 SOMATOM Sessions · May 2010 ·
  11. 11. Coverstory3 3 Perfusion CT imaging is in- creasingly be- ing adopted in daily routine. This function overcomes the limitations of a static detector design, which provides full brain coverage, and the poten- tial for improve- ment in diag- nostic accuracy for acute stroke.moves the patient in and out of the a smooth, fast, and user-friendly work- graphy adds approximately 10 minutesgantry over the desired scan range. Lin flow. A number of steps are automated, to the acute stroke workflow. “That’s nothas recently switched to a SOMATOM including motion correction, bone seg- a lot of time considering that the addi-Definition AS+ Scanner with all the mentation, arterial input function deter- tional information provided by the CTadvantages of full brain coverage. “With mination, and vascular pixel elimination. Perfusion and the CT Angiography maythe increased coverage, we now expect The software allows for simultaneous have very important implications for thefurther improvement in acute stroke visualization of functional parametric patient’s treatment and management,”detection accuracy, as well as the full maps of cerebral blood flow, cerebral Lin says.delineation of the ischemic penumbra blood volume, time to peak, mean tran-and the infarct core,” Lin says. sit time and other clinically important Reducing Dose in CT PerfusionThe stroke imaging workflow at NYU information. With the click of a button, Lin recognizes that, while the use of CTLangone Medical Center also includes clinicians can toggle between axial, Perfusion is moving from academica CT Angiography immediately following sagittal and coronal reformations. medical centers to community hospitals,the CT Perfusion exam to evaluate clot Lin and his colleagues acquire the CT some barriers to its widespread adoptionlocation, clot burden, and collateral re- Perfusion data for the whole brain in remain. Chief among them is a concerncruitment. Lin adds that the information just 45 seconds. Next, CT Angiography about the radiation dose associated withis also used for planning interventional data from the aortic arch through the the acquisition of CT Perfusion and CTprocedures such as mechanical throm- whole brain, a scan range of typically Angiography data. The use of Siemensbectomy. more than 30 cm, is acquired in a couple 4D Noise Reduction, however, can re-Lin says the fast image acquisition of of seconds to deliver valuable infor- duce the radiation noise of dynamic CTthe SOMATOM Definition AS+ 128-slice mation about the feeding vessels that Perfusion. The reconstruction techniquescanner, combined with the rapid post- are not covered by the initial perfusion treats the static anatomical informationprocessing of the Siemens syngo Volume scan. Post-processing takes an additional differently from the dynamically chang-Perfusion CT Neuro software, allows three to five minutes. In total, when ing perfusion information that resultsreading physicians to arrive quickly at an time for interpretation is accounted for, from the in and outflow of the contrastappropriate treatment decision through the use of CT Perfusion and CT Angio- agent. By sampling multiple passes over SOMATOM Sessions · May 2010 · 11