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Sample records for cardiac multidetector ct

  1. Cardiac Computed Tomography (Multidetector CT, or MDCT)

    Science.gov (United States)

    ... Blood Pressure Tools & Resources Stroke More Cardiac Computed Tomography (Multidetector CT, or MDCT) Updated:Sep 3,2015 What is Computerized Tomography (CT)? CT is a noninvasive test that uses ...

  2. Cardiac causes of pulmonary arterial hypertension: assessment with multidetector CT

    Energy Technology Data Exchange (ETDEWEB)

    Hoey, Edward T.D.; Gopalan, Deepa; Agrawal, S.K.B. [Papworth Hospital, Cambridge (United Kingdom); Screaton, Nicholas J. [Papworth Hospital, Cambridge (United Kingdom); Papworth Hospital NHS Trust, Diagnostic Centre, Department of Radiology, Papworth Everard, Cambridgeshire (United Kingdom)

    2009-11-15

    The causes of pulmonary arterial hypertension (PAH) are diverse and include multiple congenital and acquired cardiac diseases as well as diseases primarily affecting the pulmonary vasculature, lung, pleura and chest wall. The traditional role of CT in evaluating PAH includes assessment of pulmonary vasculature and lung parenchyma with limited assessment of the heart. Advances in multidetector CT technology with improved spatial and temporal resolution now permit accurate delineation of cardiac morphology. CT pulmonary angiography (CTPA) is widely utilised in the workup of patients with suspected pulmonary vascular disease and can identify both pulmonary and cardiac causes. As the initial presentation for CTPA is often precipitated by nonspecific, unexplained symptoms and therefore undertaken by a general radiologist, it is important that a systematic approach to the interpretation of these studies, including cardiac evaluation, is routinely adopted. This paper reviews the CT evaluation in pulmonary hypertension with a particular focus on the cardiac causes, their subclassification into congenital systemic to pulmonary shunts and secondary to left heart disease, and their imaging features. It emphasises the use of a systematic approach to interpretation of CTPA examinations both in patients with known PAH and those with previously unsuspected disease. (orig.)

  3. Accessory cardiac bronchus: Proposed imaging classification on multidetector CT

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    Kim, Kang Min; Kim, Young Tong; Han, Jong Kyu; Jou, Sung Shick [Dept. of Radiology, Soonchunhyang University College of Medicine, Cheonan Hospital, Cheonan (Korea, Republic of)

    2016-02-15

    To propose the classification of accessory cardiac bronchus (ACB) based on imaging using multidetector computed tomography (MDCT), and evaluate follow-up changes of ACB. This study included 58 patients diagnosed as ACB since 9 years, using MDCT. We analyzed the types, division locations and division directions of ACB, and also evaluated changes on follow-up. We identified two main types of ACB: blind-end (51.7%) and lobule (48.3%). The blind-end ACB was further classified into three subtypes: blunt (70%), pointy (23.3%) and saccular (6.7%). The lobule ACB was also further classified into three subtypes: complete (46.4%), incomplete (28.6%) and rudimentary (25%). Division location to the upper half bronchus intermedius (79.3%) and medial direction (60.3%) were the most common in all patients. The difference in division direction was statistically significant between the blind-end and lobule types (p = 0.019). Peribronchial soft tissue was found in five cases. One calcification case was identified in the lobule type. During follow-up, ACB had disappeared in two cases of the blind-end type and in one case of the rudimentary subtype. The proposed classification of ACB based on imaging, and the follow-up CT, helped us to understand the various imaging features of ACB.

  4. Method for Automatic Tube Current Selection for Obtaining a Consistent Image Quality and Dose Optimization in a Cardiac Multidetector CT

    OpenAIRE

    Qi, Weiwei; Li, Jianying; Du, Xiangke

    2009-01-01

    Objective To evaluate a quantitative method for individually adjusting the tube current to obtain images with consistent noise in electrocardiogram (ECG)-gated CT cardiac scans. Materials and Methods The image noise from timing bolus and cardiac CT scans of 80 patients (Group A) who underwent a 64-row multidetector (MD) CT cardiac examination with patient-independent scan parameters were analyzed. A formula was established using the noise correlation between the timing bolus and cardiac scans...

  5. Current development of cardiac imaging with multidetector-row CT

    International Nuclear Information System (INIS)

    Multidector-row CT (MDCT) with retrospective ECG gating allows scanning the entire heart with 1.25 mm slice thickness and 250 ms effective exposure time within 35 s investigation time. The resulting images allow for an accurate high-resolution assessment of morphological detail of both the coronary arteries and the cardiac chambers. Performing a contrast-enhanced MDCT angiography (MD-CTA) in addition to a non-enhanced scan for the detection and quantification of coronary calcifications may be indicated in patients with atypical chest pain and in young patients with high cardiovascular risk. This group of patients may show non-calcified plaques as the first sign of their coronary artery disease. As the proximal part of the coronary arteries is well displayed by MD-CTA it also helps to delineate the course in anomalous coronary vessels. Additional information is drawn from the preoperative use of MD-CTA do determine the distance of the left internal mammarian artery to the left anterior descending coronary artery prior to minimal invasive bypass grafting. Additional indications for MD-CTA are the non-invasive follow up after venous bypass grafting, PTCA, and coronary stent interventions. MD-CTA allows following the course of the coronary vessels to the level of third generation coronary segmental arteries. A definite diagnosis to rule out coronary artery disease can be reliably made in vessels with a diameter of 1.5 mm or greater. With MDCT a number of different atherosclerotic changes can be observed in diseased coronary arteries. Non-stenotic lesions may show tiny calcifications surrounded by large areas of irregularly distributed soft tissue. Calcifications in this type of atherosclerotic coronary artery wall changes appear as 'the tip of iceberg'. Heavy calcifications usually tend to be non-stenotic because of vessel remodelling resulting in a widening of the coronary vessel lumen. Therefore, heavy calcifications appear to act like an 'internal stent' for a

  6. Cardiac carcinoid: tricuspid delayed hyperenhancement on cardiac 64-slice multidetector CT and magnetic resonance imaging.

    LENUS (Irish Health Repository)

    Martos, R

    2012-02-01

    INTRODUCTION: Carcinoid heart disease is a rare condition in adults. Its diagnosis can be easily missed in a patient presenting to a primary care setting. We revised the advantages of using coronary multidetector computed tomography (MDCT) and cardiac magnetic resonance imaging (MRI) in diagnosing this condition. MATERIALS AND METHODS: We studied a 65-year-old patient with carcinoid heart disease and right heart failure using transthoracic Doppler-echocardiogram, cardiac MDCT and MRI. Cardiac echocardiogram revealed marked thickening and retraction of the tricuspid leaflets with dilated right atrium and ventricle. Cardiac MDCT and MRI demonstrated fixation and retraction of the tricuspid leaflets with delayed contrast hyperenhancement of the tricuspid annulus. CONCLUSION: This case demonstrates fascinating imaging findings of cardiac carcinoid disease and highlights the increasing utility of contrast-enhanced MRI and cardiac MDCT in the diagnosis of this interesting condition.

  7. Role of Multidetector CT in Evaluation of Acute Chest Pain: Non-Cardiac Vascular and Pulmonary Causes

    Directory of Open Access Journals (Sweden)

    Rania S Sayed *, Hisham M Mansour **, Mohammad H Khaleel ***, Sherif H Abo Gamra ** and Merhan A Nasr

    2013-04-01

    Full Text Available Background: Triage of patients with acute chest pain is one of the most important issues currently facing physicians in the emergency department. Acute chest pain may be a symptom of a number of serious conditions and is generally considered a medical emergency. The causes of acute chest pain range from non-serious to life threatening. A rapid, accurate and cost-effective approach for the evaluation of emergency department patients with chest pain is needed. Aim of the work: This work aims to emphasize the role of multidetector CT in assessment of non-cardiac vascular and pulmonary causes of acute chest pain.Method: The studied group included 89 patients (59 men and 30 women presented by acute chest pain. All patients were subjected to MDCT and/or MDCT angiography using a Toshiba 64 detectors CT scanner. Results: The high spatial resolution and relatively non-invasive nature make MSCT angiography a strong and serious competitor to established vascular imaging techniques. Having the additional ability to simultaneously acquire information on other organs, which enables the early diagnosis of complications. Conclusion: Continued technical improvements in acquisition speed and spatial resolution of computed tomography images, and development of more efficient image reconstruction algorithms which reduce patient exposure to radiation and contrast result in increased popularity of MDCT.

  8. Heart-rate-adapted image reconstruction in multidetector-row cardiac CT: influence of physiological and technical prerequisite on image quality

    International Nuclear Information System (INIS)

    The purpose of this study was to develop strategies for optimal image reconstruction in multidetector-row cardiac CT and to discuss the results in the context of individual heart rate, cardiac physiology, and technical prerequisite. Sixty-four patients underwent multidetector-row cardiac CT. Depending on the heart rate either a single-segmental reconstruction (SSR) or an adaptive two-segmental reconstruction (ASR) was applied. Image reconstruction was done either antegrade (a) or retrograde (r) in relation to the R-peak. Reconstruction of all data sets was performed at multiple time points within the t-wave/p-wave interval, differing from each other by 50 ms. In addition, each reconstruction was assigned to one of six reconstruction intervals (A-F), each corresponding to a specific event in the cardiac cycle. While no significant time points were found for absolute values, the following interval/reconstruction technique combinations provided significant better image quality: F/r at HR 65 bpm for all segments (p≤0.002). The results show that in order to achieve optimal image quality, image reconstruction has to be adjusted to each patient's ECG curve and heart rate individually. The moment of reconstruction should be determined as absolute rather than as relative distance from the previous R-peak. (orig.)

  9. Cardiac multidetector row CT before percutaneous coronary intervention as a treatment guide for chronic total occlusion cardiac multidetector row CT before percutaneous coronary intervention as a treatment guide for chronic total occlusion

    International Nuclear Information System (INIS)

    The goal of this study was to investigate imaging results from a coronary CT angiography (CCTA) in chronic coronary total occlusion (CTO) before percutaneous coronary intervention (PCI). In 74 patients with CTO, 34 patients was evaluated by using a 64-row multidetector CT scanner prior to the PCI and 40 control subjects with CTO, who only took PCI, were included. The multiplanar reformation of the heart chambers and three-dimensional CT images were used for determining an optimal view. We analyzed and evaluated the success rates of PCI, length of occluded vessel, calcified plaques, occluded side-branches, tapered occlusion, > 45 degrees angulation of occluded artery, and myocardial density < 50 Hounsfield unit (HU). Success rates of PCI in the two groups, the control group and the experimental group, were not statistically different (p > 0.05). The mean length of occluded arteries was measured as 25 +/- 11 mm and 26 cases (74%) had an occlusion length > 2 cm. Calcified plaques proximal to occlusion were detected in 19 cases (54%). Occluded side branches, tapered occlusion, > 45 degrees angulation of occluded artery, and myocardial density < 50 HU were in 11 cases (32%), 9 cases (27%), 6 cases (18%), and 5 cases (15%), respectively. Although there was no correlation between the CCTA findings before PCI and the success rate of PCI, common findings of CCTA in CTO included an occlusion length > 2 cm and calcified plaques proximal to occluded arteries.

  10. Cardiac multidetector row CT before percutaneous coronary intervention as a treatment guide for chronic total occlusion cardiac multidetector row CT before percutaneous coronary intervention as a treatment guide for chronic total occlusion

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    Kim, Dong Hun; Choi, Dong Hyun [Dept. of Radiology, Chosun University Hospital, Gwangju (Korea, Republic of); Lee, Nae Hee [Dept. of Internal Medicine, Soonchunhyang University Bucheon Hospital, Bucheon (Korea, Republic of)

    2015-03-15

    The goal of this study was to investigate imaging results from a coronary CT angiography (CCTA) in chronic coronary total occlusion (CTO) before percutaneous coronary intervention (PCI). In 74 patients with CTO, 34 patients was evaluated by using a 64-row multidetector CT scanner prior to the PCI and 40 control subjects with CTO, who only took PCI, were included. The multiplanar reformation of the heart chambers and three-dimensional CT images were used for determining an optimal view. We analyzed and evaluated the success rates of PCI, length of occluded vessel, calcified plaques, occluded side-branches, tapered occlusion, > 45 degrees angulation of occluded artery, and myocardial density < 50 Hounsfield unit (HU). Success rates of PCI in the two groups, the control group and the experimental group, were not statistically different (p > 0.05). The mean length of occluded arteries was measured as 25 +/- 11 mm and 26 cases (74%) had an occlusion length > 2 cm. Calcified plaques proximal to occlusion were detected in 19 cases (54%). Occluded side branches, tapered occlusion, > 45 degrees angulation of occluded artery, and myocardial density < 50 HU were in 11 cases (32%), 9 cases (27%), 6 cases (18%), and 5 cases (15%), respectively. Although there was no correlation between the CCTA findings before PCI and the success rate of PCI, common findings of CCTA in CTO included an occlusion length > 2 cm and calcified plaques proximal to occluded arteries.

  11. Multidetector CT and MRI in pancreatic diseases

    International Nuclear Information System (INIS)

    Multidetector CT and MRI are the most efficient non invasive techniques in the assessment of pancreatic diseases. As with MRI, multidetector CT has now become an all in one examination using 2 D and 3 D multiplanar reformations with the ability to perform with high accuracy: a) vascular assessment using MIP reconstruction and b) biliary and pancreatic ducts assessment using minIP reconstruction. This review compares and illustrates the respective advantages of MRI and multidetector CT in the assessment of pancreatic diseases. (authors)

  12. Cardiac Multi-detector CT Segmentation Based on Multiscale Directional Edge Detector and 3D Level Set.

    Science.gov (United States)

    Antunes, Sofia; Esposito, Antonio; Palmisano, Anna; Colantoni, Caterina; Cerutti, Sergio; Rizzo, Giovanna

    2016-05-01

    Extraction of the cardiac surfaces of interest from multi-detector computed tomographic (MDCT) data is a pre-requisite step for cardiac analysis, as well as for image guidance procedures. Most of the existing methods need manual corrections, which is time-consuming. We present a fully automatic segmentation technique for the extraction of the right ventricle, left ventricular endocardium and epicardium from MDCT images. The method consists in a 3D level set surface evolution approach coupled to a new stopping function based on a multiscale directional second derivative Gaussian filter, which is able to stop propagation precisely on the real boundary of the structures of interest. We validated the segmentation method on 18 MDCT volumes from healthy and pathologic subjects using manual segmentation performed by a team of expert radiologists as gold standard. Segmentation errors were assessed for each structure resulting in a surface-to-surface mean error below 0.5 mm and a percentage of surface distance with errors less than 1 mm above 80%. Moreover, in comparison to other segmentation approaches, already proposed in previous work, our method presented an improved accuracy (with surface distance errors less than 1 mm increased of 8-20% for all structures). The obtained results suggest that our approach is accurate and effective for the segmentation of ventricular cavities and myocardium from MDCT images. PMID:26319010

  13. Cardiac CT

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    Dewey, Marc [Charite - Universitaetsmedizin Berlin (Germany). Inst. fuer Radiologie

    2011-07-01

    Computed tomography of the heart has become a highly accurate diagnostic modality that is attracting increasing attention. This extensively illustrated book aims to assist the reader in integrating cardiac CT into daily clinical practice, while also reviewing its current technical status and applications. Clear guidance is provided on the performance and interpretation of imaging using the latest technology, which offers greater coverage, better spatial resolution, and faster imaging. The specific features of scanners from all four main vendors, including those that have only recently become available, are presented. Among the wide range of applications and issues to be discussed are coronary artery bypass grafts, stents, plaques, and anomalies, cardiac valves, congenital and acquired heart disease, and radiation exposure. Upcoming clinical uses of cardiac CT, such as plaque imaging and functional assessment, are also explored. (orig.)

  14. Usefulness of multidetector-row CT (MD-CT) for assessment of coronary artery stenosis

    International Nuclear Information System (INIS)

    Coronary arteries stenosis were evaluated in 49 cases by volume rendering (VR) and partial maximum intensity projection (partial MIP) using multidetector-row CT (MD-CT). Left main trunk (LMT) and left anterior descending artery (LAD) were less affected by cardiac pulsation artifact and presented good images. Right coronary artery (RCA) was affected by cardiac pulsation artifact and image quality was inferior as compared to left coronary artery (LCA). It is suggested that MD-CT is useful for assessment of coronary artery stenosis, especially LCA. (author)

  15. Multidetector CT of blunt abdominal trauma.

    Science.gov (United States)

    Soto, Jorge A; Anderson, Stephan W

    2012-12-01

    The morbidity, mortality, and economic costs resulting from trauma in general, and blunt abdominal trauma in particular, are substantial. The "panscan" (computed tomographic [CT] examination of the head, neck, chest, abdomen, and pelvis) has become an essential element in the early evaluation and decision-making algorithm for hemodynamically stable patients who sustained abdominal trauma. CT has virtually replaced diagnostic peritoneal lavage for the detection of important injuries. Over the past decade, substantial hardware and software developments in CT technology, especially the introduction and refinement of multidetector scanners, have expanded the versatility of CT for examination of the polytrauma patient in multiple facets: higher spatial resolution, faster image acquisition and reconstruction, and improved patient safety (optimization of radiation delivery methods). In this article, the authors review the elements of multidetector CT technique that are currently relevant for evaluating blunt abdominal trauma and describe the most important CT signs of trauma in the various organs. Because conservative nonsurgical therapy is preferred for all but the most severe injuries affecting the solid viscera, the authors emphasize the CT findings that are indications for direct therapeutic intervention. PMID:23175542

  16. Multidetector CT of the Pancreas

    Directory of Open Access Journals (Sweden)

    Rossella Graziani

    2008-07-01

    Full Text Available Purpose. This book is a practical overview of pancreatic computer tomography (CT based on the large experience of the contributors. It is dedicated to Carlo Procacci a well known radiologist of Verona who died in 2004. Content. The book is divided into 10 chapters covering the different aspects of diagnostic CT of the pancreas. The various radiological aspects of acute and chronic pancreatitis, exocrine and endocrine pancreatic cancer (adenocarcinoma, neuroendocrine tumors, cystic cancer, rare neoplasms, traumatic abnormalities, imaging aspects of the gland after surgery and finally imaging findings after pancreas transplantation are reported in detail. Comment. We would emphasize that the characteristics of imaging of the common pancreatic diseases are described in addition to unusual or rare aspects of pancreatic pathology. The iconography is very rich and it is of excellent quality and it will help the radiologist to deal with individual cases particularly complex. Another important aspect of the book is that the initial approach of the various pancreatic diseases is based on clinical, surgical and pathological aspects and their relationship with imaging findings. Limitation. It is a great pity that the book for its importance is written in Italian language and for this reason it can not have an international appreciation. Final note. The radiologists will find in the book all the information useful for their daily practice. The internists, gastroenterologists and surgeons also will found useful information to better understand the information given by the modern CT radiology.

  17. Marketing cardiac CT programs.

    Science.gov (United States)

    Scott, Jason

    2010-01-01

    There are two components of cardiac CT discussed in this article: coronary artery calcium scoring (CACS) and coronary computed tomography angiography (CCTA).The distinctive advantages of each CT examination are outlined. In order to ensure a successful cardiac CT program, it is imperative that imaging facilities market their cardiac CT practices effectively in order to gain a competitive advantage in this valuable market share. If patients receive quality care by competent individuals, they are more likely to recommend the facility's cardiac CT program. Satisfied patients will also be more willing to come back for any further testing.

  18. Multidetector CT angiography in Takayasu arteritis

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    Khandelwal, Niranjan; Kalra, Naveen [Department of Radiodiagnosis and Imaging, Post Graduate Institute of Medical Education and Research, Chandigarh 160012 (India); Garg, Mandeep Kumar, E-mail: gargmandeep@hotmail.com [Department of Radiodiagnosis and Imaging, Post Graduate Institute of Medical Education and Research, Chandigarh 160012 (India); Kang, Mandeep; Lal, Anupam [Department of Radiodiagnosis and Imaging, Post Graduate Institute of Medical Education and Research, Chandigarh 160012 (India); Jain, Sanjay [Department of Internal Medicine, Post Graduate Institute of Medical Education and Research, Chandigarh 160012 (India); Suri, Sudha [Department of Radiodiagnosis and Imaging, Post Graduate Institute of Medical Education and Research, Chandigarh 160012 (India)

    2011-02-15

    Objective: To analyse the spectrum of Takayasu's arteritis (TA) on multidetector CT angiography (MDCTA). Materials and methods: A retrospective analysis of the MDCTA findings was performed on 15 patients clinically diagnosed as Takayasu's arteritis. The spectrum and incidence of imaging findings on CTA were compared to studies in literature on catheter angiography in Takayasu's arteritis. Laboratory parameters were available in nine patients. The disease was considered active if erythrocyte sedimentation rate (ESR) levels were elevated and 'C' reactive protein (CRP) was positive. An attempt was made to correlate disease activity with the imaging findings. Results: Ascending aorta, arch of aorta and descending thoracic aorta were involved in 14 out of 15 (93%) patients. The wall thickness varied between 1 and 10 mm with maximal involvement in arch and descending thoracic aorta. Major neck vessels were involved in 11 (73%) patients with most pronounced changes seen in the brachiocephalic trunk, left common carotid artery (CCA) and left subclavian artery (SCA). Abdominal aorta and its branches were involved in all the 11 (100%) patients in whom abdominal CTA was performed. Celiac axis and SMA were involved in 10 (91%) and seven (64%) patients, respectively while renal artery stenosis was present in five (45%) patients. In six patients, ESR was elevated and CRP was positive indicating active disease. All patients in whom the laboratory parameters were available showed mural thickening in the aorta and at least one of the neck vessels except for one patient with inactive disease who had aortic mural thickening only. Conclusion: MDCTA provides information about both the vessel wall and lumen in patients with Takayasu's disease.

  19. CT paging arteriography with a multidetector-row CT. Advantages in splanchnic arterial imaging

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    Kobayashi, Seiji [Keio Univ., Tokyo (Japan). School of Medicine

    1999-11-01

    The purpose of this study is to assess the utility of CT paging arteriography with a multidetector-row CT as a replacement for conventional angiography in the evaluation of splanchnic arterial anomalies. Sixty-three patients underwent CT paging arteriography with a multidetector-row CT. In the 56 patients with conventional angiographic correlation, there was only one minor disagreement with CT paging arteriography. In the 7 patients who underwent IVDSA (intra venous digital subtraction angiography), CT paging arteriography defined four hepatic arterial anomalies which could not be depicted by IVDSA. In conclusion, CT paging arteriography provides noninvasive means to identify splanchnic arterial anomalies. (author)

  20. Multidetector Row CT Detection of a Patent Foramen Ovale Causing Neurologic Deficits in an Adolescent: A Case Report

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    Lee, Jung Bin [Dept. of Radiology, Soonchunhyang University College of Medicine, Bucheon (Korea, Republic of); Kim, Dong Hun; Oh, Jae Hee [Dept. of Radiology, Chosun University College of Medicine, Gwangju (Korea, Republic of); Seo, Hye Sun [Dept. of Internal Medicine, Soonchunhyang University College of Medicine, Bucheon (Korea, Republic of); Suk, Eun Ha [Dept. of Anesthesiology and Pain Medicine, Asan Medical Center, Seoul (Korea, Republic of)

    2012-02-15

    A patent foramen ovale (PFO) is a persisting fetal circulation structural abnormality that can cause neurologic deficits such as migraine and cryptogenic stroke. Here we report a case of PFO diagnosed by cardiac multidetector row CT in an adolescent male with chronic migraine and stroke.

  1. Multidetector Row CT Detection of a Patent Foramen Ovale Causing Neurologic Deficits in an Adolescent: A Case Report

    International Nuclear Information System (INIS)

    A patent foramen ovale (PFO) is a persisting fetal circulation structural abnormality that can cause neurologic deficits such as migraine and cryptogenic stroke. Here we report a case of PFO diagnosed by cardiac multidetector row CT in an adolescent male with chronic migraine and stroke.

  2. Multi-detector CT knee arthrography - initial experience

    International Nuclear Information System (INIS)

    Full text: Traditional plain film arthrography can achieve reasonable accuracy and is an accepted method of investigation of patients with knee pain and possible meniscal tear. Multi-detector CT can potentially provide a more detailed and accurate examination due to its high-resolution crosssectional and multi-planar capabilities. The aim of this study was to assess the accuracy of our technique. All patients who underwent a multi-detector CT knee arthrogram in an initial 8 month period were identified. Initially the referring clinician was contacted. If the patient was referred to an orthopaedic surgeon the outcome of orthopaedic review was recorded using clinical, arthroscopic and / or MRI follow-up of the patient population. One hundred and twelve patients had a Multi-detector CT knee arthrogram performed within and 8 month period. Follow-up information was received in 69.7% of patients. Of these 68.9% had orthopaedic assessment - of which 69.2% underwent a knee arthroscopy.There was total agreement of findings in 67%, agreement of meniscal findings in 67% and chondral findings in 100%. Overall, orthopaedic opinion agreed with CT findings in 76.9%. At this stage, all meniscal tears not described in the initial CT arthrogram report have in retrospect been visible. Multi-detector CT knee arthrography is an accurate and elegant technique for investigation of knee pain, providing information in a format familiar to those reporting knee MRI. There is an initial learning curve. The technique is particularly useful in chondral assessment. It is accurate for meniscal pathology, although caution and recognition of potential pitfalls is required. Copyright (2002) Blackwell Science Pty Ltd

  3. Sacroiliitis in Ankylosing Spondylitis: Comparison with Multidetector Row CT and Plain Radiography

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    Yu, Ji Youn; Joo, Kyung Bin; Choi, Byeong Kyoo; Ryu, Jeong Ah; Kim, Tae Hwan; Choi, Woo Jung [Hanyang University Hospital, Seoul (Korea, Republic of)

    2009-03-15

    The objective of our study was to compare multidetector row CT and the plain radiographs for making the diagnosis and grading the sacroiliitis that accompanies ankylosing spondylitis. We wanted to determine the role of multidetector row CT for the evaluation of the sacroilitis in patients with ankylosing spondylitis. One hundred ninety two patients with clinically suspected ankylosing spondylitis were evaluated by conventional radiography and multidetector row CT. Two musculoskeletal radiologists retrospectively analyzed the images, and they graded the sacroiliitis using the modified New York Criteria. Multidetector row CT demonstrated a significantly higher sensitivity (74.5%, 83.3%) than did plain radiography (59.9%, 66.7%) for detecting early sacroiliitis (p<0.05). Multidetector row CT showed a higher grade of sacroiliitis in 114 and 127 of 384 sacroiliac joints. Performing multidetector row CT rather than plain radiography for making the diagnoses of accompanying ankylosing spondylitis allows an early start of treatment with a subsequently improved prognosis

  4. Controversies in imaging of hepatocellular carcinoma: multidetector CT (MDCT)

    OpenAIRE

    Silverman, Paul M.; Szklaruk, Janio

    2005-01-01

    Primary hepatocellular carcinoma (HCC) is a significant tumor worldwide and represents the most common primary hepatic neoplasm. Staging criteria are important for appreciation of timely work up of these neoplasms in contradiction with surgical colleagues. This article demonstrates the appearance of HCC on multiphasic, multidetector CT (MDCT) and relates these findings to current staging criteria. The variable appearance on different planes of contrast is critical to appreciate in staging thi...

  5. Esophageal injuries: Spectrum of multidetector row CT findings

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    Lutio di Castelguidone, Elisabetta de [Department of Radiology, I.N.T., IRCCS Fondazione G. Pascale, Via M. Semmola, I-80131 Naples (Italy)]. E-mail: e.delutio@virgilio.it; Merola, Stefanella [Department of Diagnostic Imaging, ' A. Cardarelli' Hospital, I-80131 Naples (Italy); Pinto, Antonio [Department of Diagnostic Imaging, ' A. Cardarelli' Hospital, I-80131 Naples (Italy); Raissaki, Maria [Department of Radiology, University Hospital of Iraklion, University of Crete Medical School, P.O. Box 1352, 711 10 Iraklion Crete (Greece); Gagliardi, Nicola [Department of Diagnostic Imaging, ' A. Cardarelli' Hospital, I-80131 Naples (Italy); Romano, Luigia [Department of Diagnostic Imaging, ' A. Cardarelli' Hospital, I-80131 Naples (Italy)

    2006-09-15

    Background: Aim of this study is to illustrate the multidetector row computed tomographic findings related to oesophageal injuries and their significance for therapeutic decisions. Method: From April 2002 to April 2005 we studied 16 patients with suspected oesophageal injury. Ten patients underwent standard chest radiograph, while five patients with suspected foreign body ingestion were submitted to cervical plain film and gastrografin swallow study. All 16 patients underwent multidetector row CT examination. Results: In six patients with cervical, thoracic and abdominal trauma, CT showed the presence of thoracic traumatic lesions and findings suggestive of perforation of the oesophagus. In five patients with foreign body ingestion cervical radiography was positive in only one case, while CT showed the presence of a foreign body in all cases. In three patients with post-intubation complications, CT showed the presence of perioesophageal fluid collection containing small gas bubbles in two cases and an oesophageal-aortic fistula in one case. In the remaining two patients with suspected spontaneous oesophageal perforation, CT demonstrated an oesophageal wall oedema and thickening in one case, and oesophageal fluid distension with perioesophageal small bubbles gas and fluid in the second case. Conclusion: Oesophageal injuries, when complicated with perforation, constitute a life-threatening condition. Knowledge of the CT signs of oesophageal injuries has important implications for the role of imaging at the time of initial diagnosis.

  6. ROLE OF MULTIDETECTOR CT IN EVALUATION OF NECK LESIONS

    Directory of Open Access Journals (Sweden)

    Reena Mathur

    2016-06-01

    Full Text Available AIMS AND OBJECTIVES To find out the role of multidetector computed tomography in the evaluation of neck lesions with respect to evaluation of the size, location and extent of tumour. Extension of tumour infiltrating into surrounding vascular and visceral structures. To correlate the findings of MD-CT with final diagnosis by biopsy. MATERIAL AND METHODS Data for the study was collected from patients with suspected neck lesions attending Department of Radio-diagnosis, J.L.N. Medical College and Associated Group of Hospitals, Ajmer, Rajasthan. A prospective study was conducted over a period (From 1st March 2014 to 31 Aug. 2015 on patients with clinically suspected neck lesions or patients who were diagnosed to have neck lesion on ultrasound and were referred to CT for further characterisation. The patients presented with symptoms of palpable neck mass and neck pain. Patients were evaluated using multidetector CT. A provisional diagnosis was made after CT scan and these findings were correlated with histopathology/surgical findings as applicable. RESULT In the present study, 97 out of 100 cases were correctly characterised by computed tomography giving an accuracy of 97%. One case of buccal carcinoma was wrongly diagnosed as benign lesion and another case of malignant lymph node was inaccurately diagnosed as benign lymph node, also another case of benign lymph node was inaccurately diagnosed as malignant lymph node. CONCLUSION Multidetector Computed Tomography of the neck has improved the localisation and characterisation of neck lesions. Accurate delineation of disease by CT scan provides a reliable preoperative diagnosis, plan for radiotherapy ports and posttreatment followup. However, histopathology still remains the gold standard as CT is not 100% accurate.

  7. Cardiac pathologies incidentally detected with non-gated chest CT; Inzidentelle Pathologien des Herzens im Thorax-CT

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    Scherer, Axel; Kroepil, P.; Lanzman, R.S.; Moedder, U. [Inst. fuer Radiologie, Universitaetsklinikum Duesseldorf, Heinrich-Heine-Univ. (Germany); Choy, G.; Abbara, S. [Cardiovascular Imaging Section, Massachusetts General Hospital, Harvard Medical School (United States)

    2009-12-15

    Cardiac imaging using electrocardiogram-gated multi-detector computed tomography (MDCT) permits noninvasive diagnosis of congenital and acquired cardiac pathologies and has thus become increasingly important in the last years. Several studies investigated the incidence and relevance of incidental extracardiac structures within the lungs, mediastinum, chest wall, and abdomen with gated coronary CT. This resulted in the general acceptance of the review of extracardiac structures as a routine component of coronary CT interpretation. On the other hand radiologists tend to neglect pericardial and cardiac pathologies in non-gated chest CT, which is primarily performed for the evaluation of the respiratory system or for tumor staging. Since the introduction of multi-detector spiral CT technology, the incidental detection of cardiac and pericardial findings has become possible using non-gated chest CT. This article reviews the imaging appearances and differential diagnostic considerations of incidental cardiac entities that may be encountered in non-gated chest CT. (orig.)

  8. Multidetector-row CT for spinal diseases

    International Nuclear Information System (INIS)

    Multi-detector-row CT is called second stage helical CT because it produces multi-volume slices in a short time. We have observed sagittal, coronal images for spinal diseases by this CT. Thirty-three sagittal images out of 39 post-myelography for spinal diseases were good images of compression of the dural sac, and 8 coronal images post myelography were good images of compression of the dural sac and spinal nerve roots. We obtained 11 sagittal images for OPLL, and all images were nearly equal to that of tomography. However, spinal tumors and inflammatory diseases are more easily obtained using MRI. Multi-detector-row CT is useful for spinal degenerative diseases. (author)

  9. CT portography by multidetector helical CT. Comparison of three rendering models

    Energy Technology Data Exchange (ETDEWEB)

    Nakayama, Yoshiharu; Imuta, Masanori; Funama, Yoshinori; Kadota, Masataka; Utsunomiya, Daisuke; Shiraishi, Shinya; Hayashida, Yoshiko; Yamashita, Yasuyuki [Kumamoto Univ. (Japan). School of Medicine

    2002-12-01

    The purpose of this study was to assess the value of multidetector CT portography in visualizing varices and portosystemic collaterals in comparison with conventional portography, and to compare the visualizations obtained by three rendering models (volume rendering, VR; minimum intensity projection, MIP; and shaded surface display, SSD). A total of 46 patients with portal hypertension were examined by CT and conventional portography for evaluation of portosystemic collaterals. CT portography was performed by multidetector CT (MD-CT) scanner with a slice thickness of 2.5 mm and table feed of 7.5 mm. Three types of CT portographic models were generated and compared with transarterial portography. Among 46 patients, 48 collaterals were identified on CT transverse images, while 38 collaterals were detected on transarterial portography. Forty-four of 48 collaterals identified on CT transverse images were visualized with the MIP model, while 34 and 29 collaterals were visualized by the VR and SSD methods, respectively. The average CT value for the portal vein and varices was 198 HU with data acquisition of 50 sec after contrast material injection. CT portography by multidetector CT provides excellent images in the visualization of portosystemic collaterals. The images of collaterals produced by MD-CT are superior to those of transarterial portography. Among the three rendering techniques, MIP provides the best visualization of portosystemic collaterals. (author)

  10. Stress myocardial perfusion imaging with multidetector CT

    NARCIS (Netherlands)

    A. Rossi (Alexia); D. Merkus (Daphne); E. Klotz (Ernst); N.R.A. Mollet (Nico); P.J. de Feyter (Pim); G.P. Krestin (Gabriel)

    2014-01-01

    textabstractComputed tomographic (CT) coronary angiography is a well-established, noninvasive imaging modality for detection of coronary stenosis, but it has limited accuracy in demonstrating whether a coronary stenosis is hemodynamically significant. An additional functional test is often required

  11. Multidetector CT for congenital heart patients: what a paediatric radiologist should know

    Energy Technology Data Exchange (ETDEWEB)

    Paul, Jean-Francois; Rohnean, Adela; Sigal-Cinqualbre, Anne [Radiology Unit, Marie Lannelongue Hospital, Plessis-Robinson (France)

    2010-06-15

    Multidetector CT (MDCT) is increasingly used for imaging congenital heart disease (CHD) patients in addition to echocardiography, due to its ability to provide high quality three-dimensional images, giving a comprehensive evaluation of complex heart malformations. Using 4-slice or 16-slice CT, diagnostic information in CHD patients is limited to extra-cardiac anatomy, mainly the pulmonary arteries, aorta and venous connections. Due to high heart rates in babies however, coronary evaluation and intra-cardiac analysis were not reliable with the first generations of MDCT. Larger detector size with 64-slice CT and faster acquisition time, up to 75 ms for one slice, has progressively improved coronary and intra-cardiac visualization. Because radiation dose is the main concern, especially in children, every attempt to minimize dose whilst preserving image quality is important: the ALARA concept should always be applied in this population. The 80 kVp setting is now well accepted as a standard for more and more radiological teams involved in CT of children. Different acquisition strategies are now possible for childhood coronary imaging, using retrospective or even prospective gating. Using the latest technology, sub-mSv acquisitions are now attainable for scanning a whole thorax, providing a complete analysis of any 3-D cardiac malformation, including coronary artery course visualisation. This review will describe how technological developments have improved image quality with continuous reduction of radiation dose. (orig.)

  12. Multidetector spiral CT arthrography of the shoulder

    Energy Technology Data Exchange (ETDEWEB)

    Lecouvet, Frederic E. [Departments of Radiology and Orthopaedic Surgery, Cliniques Universitaires Saint-Luc, Universite Catholique de Louvain, Hippocrate Avenue 10/2942, 1200 Brussels (Belgium)], E-mail: frederic.lecouvet@uclouvain.be; Simoni, Paolo; Koutaissoff, Sophie; Vande Berg, Bruno C.; Malghem, Jacques; Dubuc, Jean-Emile [Departments of Radiology and Orthopaedic Surgery, Cliniques Universitaires Saint-Luc, Universite Catholique de Louvain, Hippocrate Avenue 10/2942, 1200 Brussels (Belgium)

    2008-10-15

    Although MR imaging and MR arthrography are the first choice modalities for shoulder imaging, CT arthrography (CTA) may be used successfully to address many clinical questions. The advent of submillimeter multiple detector CT technology and subsequent excellent three-plane resolution has considerably increased the quality of CTA examinations and has propelled this technique to the forefront in a growing number of indications. The combined use of iodinated contrast material for fluoroscopic confirmation of the articular position of the needle before injection of gadolinium chelates for MR arthrography offers the unique opportunity to compare CTA and MRA findings in carefully selected cases. This paper illustrates capabilities and limits of CTA for the study of rotator cuff tears, shoulder instability, cartilage lesions, anatomical variants and abnormalities of the glenoid labrum, with correlations to MR arthrography and surgical findings.

  13. Multidetector spiral CT arthrography of the shoulder

    International Nuclear Information System (INIS)

    Although MR imaging and MR arthrography are the first choice modalities for shoulder imaging, CT arthrography (CTA) may be used successfully to address many clinical questions. The advent of submillimeter multiple detector CT technology and subsequent excellent three-plane resolution has considerably increased the quality of CTA examinations and has propelled this technique to the forefront in a growing number of indications. The combined use of iodinated contrast material for fluoroscopic confirmation of the articular position of the needle before injection of gadolinium chelates for MR arthrography offers the unique opportunity to compare CTA and MRA findings in carefully selected cases. This paper illustrates capabilities and limits of CTA for the study of rotator cuff tears, shoulder instability, cartilage lesions, anatomical variants and abnormalities of the glenoid labrum, with correlations to MR arthrography and surgical findings

  14. Pneumomediastinum on Multidetector CT: The Radiologic Signs and Underlying Disorders

    Energy Technology Data Exchange (ETDEWEB)

    Oh, Soo Jin; Kim, Young Tong [Soonchunhyang University Chunan Hospital, Cheonan (Korea, Republic of)

    2011-02-15

    We can see the typical signs of pneumomediastinum on chest radiography and we can also see them on the multiplanar reformatted (MPR) image of multidetector CT (MDCT). MDCT can help to understand the anatomical feature of these signs and differentiate pneumomediastinum from pneumothorax, pneumopericardium and the Mach band effect. MDCT shows the peribronchovascular air, which reveals the Macklin effect, and it can also evaluate the underlying disorders that cause pneumomediastinum. The purpose of this pictorial essay is to inform physicians about the mechanism and anatomical features of pneumomediastinum, and to help them understand the imaging findings and underlying disorders of pneumomediastinum as seen on MDCT

  15. Comparison of CT numbers between cone-beam CT and multi-detector CT

    International Nuclear Information System (INIS)

    To compare the CT numbers on 3 cone-beam CT (CBCT) images with those on multi-detector CT (MDCT) image using CT phantom and to develop linear regressive equations using CT numbers to material density for all the CT scanner each. Mini CT phantom comprised of five 1 inch thick cylindrical models with 1.125 inches diameter of materials with different densities (polyethylene, polystyrene, plastic water, nylon and acrylic) was used. It was scanned in 3 CBCTs (i-CAT, Alphard VEGA, Implagraphy SC) and 1 MDCT (Somatom Emotion). The images were saved as DICOM format and CT numbers were measured using OnDemand 3D. CT numbers obtained from CBCTs and MDCT images were compared and linear regression analysis was performed for the density, ρ(g/cm3), as the dependent variable in terms of the CT numbers obtained from CBCTs and MDCT images. CT numbers on i-CAT and Implagraphy CBCT images were smaller than those on Somatom Emotion MDCT image (p<0.05). Linear relationship on a range of materials used for this study were ρ=0.001 H+1.07 with R2 value of 0.999 for Somatom Emotion, ρ=0.002 H+1.09 with R2 value of 0.991 for Alphard VEGA, ρ=0.001 H+1.43 with R2 value of 0.980 for i-CAT and ρ=0.001 H+1.30 with R2 value of 0.975 for Implagraphy. CT numbers on i-CAT and Implagraphy CBCT images were not same as those on Somatom Emotion MDCT image. The linear regressive equations to determine the density from the CT numbers with very high correlation coefficient were obtained on three CBCT and MDCT scan.

  16. Multidetector CT and MRI in diseases of the GI tract

    International Nuclear Information System (INIS)

    With the introduction of spiral scanning then multidetector technologies, the accuracy for diagnosing digestive tract diseases with CT has been highly improved, and CT is used more and more in the evaluation of patients with suspected gastrointestinal disorders. CT is able to demonstrate both the intramural and the extra-mural components of the disease, and has a major role in the preoperative staging and the follow-up Improvements of CT protocols, such as CT-enteroclysis, or multiplanar 2D and 3D post-processing, including now techniques for 'virtual endoscopy', lead to discuss new indications in which CT could now compete with conventional X-rays series and video-endoscopy. This precise study of the digestive wall, the peri-digestive fat, the digestive tract blood supply, may be performed by MRI, under the condition of access to high level machines and standardized protocols. MR-enteroclysis and MR-virtual colonoscopy could be performed with much lower risk for the patient, in terms of radiation dose or contrast adverse effects. Endo-luminal coils should give to MR an ultra-high resolution for analysing the different layers of the gastrointestinal wall. Learning objectives: to review how to perform CT and MRI protocols for digestive tract imaging, to recognize the CT arid MR patterns of the main digestive tract diseases, to discuss the value, limits and role of CT and MR in digestive tract diseases, to discuss the potential role of CT and MR new technological developments for digestive tract imaging in the upcoming future Conclusion: CT is nowadays a modality of choice for digestive imaging. Improvements in technologies and indications, the necessary discussion of the risks and benefits for the patient should let the radiologists consider MRI in gastrointestinal disorders as an important part of the routine activity in clinical MRI. (authors)

  17. Study of Coronary Arteries by Means of Multidetector CT; Estudio de las arterias coronarias mediante tomografia computarizada multidetector

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez, G. C.; Costas, M. I.; Delgado, C.; Velasco, M.; Tardaguila, F. [Hospital POVISA. Vigo. Pontevedra (Spain)

    2004-07-01

    Radiological study of coronary arteries has undergone major advances,especially with the incorporation of new CT multidetectors which afford temporary spatial resolution sufficient for the acquisition of high-quality images and diagnoses concerning various coronary artery abnormalities. The technique is described in terms of both facilitating data within a procedure making use of beta-blockers to slow heart rate and postprocess image reconstruction. Accordingly, our experience with a 16-detector CT and its clinical applications are illustrated. (Author)

  18. Trapping volumetric measurement by multidetector CT in chronic obstructive pulmonary disease: Effect of CT threshold

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Xiaohua; Yuan, Huishu [Department of Radiology, Peking University Third Hospital, Beijing 100191 (China); Duan, Jianghui [Medical School, Peking University, Beijing 100191 (China); Du, Yipeng; Shen, Ning; He, Bei [Department of Respiration Internal Medicine, Peking University Third Hospital, Beijing 100191 (China)

    2013-08-15

    Purpose: The purpose of this study was to evaluate the effect of various computed tomography (CT) thresholds on trapping volumetric measurements by multidetector CT in chronic obstructive pulmonary disease (COPD).Methods: Twenty-three COPD patients were scanned with a 64-slice CT scanner in both the inspiratory and expiratory phase. CT thresholds of −950 Hu in inspiration and −950 to −890 Hu in expiration were used, after which trapping volumetric measurements were made using computer software. Trapping volume percentage (Vtrap%) under the different CT thresholds in the expiratory phase and below −950 Hu in the inspiratory phase was compared and correlated with lung function.Results: Mean Vtrap% was similar under −930 Hu in the expiratory phase and below −950 Hu in the inspiratory phase, being 13.18 ± 9.66 and 13.95 ± 6.72 (both lungs), respectively; this difference was not significant (P= 0.240). Vtrap% under −950 Hu in the inspiratory phase and below the −950 to −890 Hu threshold in the expiratory phase was moderately negatively correlated with the ratio of forced expiratory volume in one second to forced vital capacity and the measured value of forced expiratory volume in one second as a percentage of the predicted value.Conclusions: Trapping volumetric measurement with multidetector CT is a promising method for the quantification of COPD. It is important to know the effect of various CT thresholds on trapping volumetric measurements.

  19. Multi-detector CT/CT angiogram assessment of acute pancreatic graft dysfunction

    International Nuclear Information System (INIS)

    Simultaneous pancreatic-kidney transplantation is the definitive treatment for patients with type 1 diabetes mellitus and renal failure. Pancreatic graft failure is an important postoperative complication and most commonly occurs as a result of pancreatitis, graft thrombosis or rejection. Distinguishing between these causes is necessary to determine timely, appropriate management and thereby potentially minimising graft loss. Multi-detector CT imaging may be used to identify the cause of pancreatic graft dysfunction when renal function is not markedly impaired.

  20. A project to design a software package for reporting multidetector CT (MDCT) doses

    International Nuclear Information System (INIS)

    Computed tomography (CT) has established itself as one of the most significant diagnostic technologies. The advent of the multidetector CT (MDCT) has made it possible to capture images to create 4D motion images for cardiac and respiratory diseases. As its usage grows, more concerns about the potential radiation risk to patients associated with various CT scanning protocols have raised from the medical imaging community and patients. This paper describes the effort to develop a modern software package to estimate and report the organ dose and effective dose values for patients undergoing the CT examinations. Original dose data were derived from a large number of Monte Carlo (MC) simulations based both on the ICRP 60 and ICRP 103 tissue-weighting coefficient using MCNPX v2.5, involving detailed CT scanner models and anatomically realistic phantoms. Detailed CT scanner X-ray sources and protocols are considered in the Monte Carlo simulations. Several of CT scanner series and different operated tube voltage have been taken into consideration. The RP1 Pregnant Women (RP1-P3, -P6 and -P9) and RP1 Adult Male (RPI-AM) and Adult Female (RPI-AF) are utilized as the phantom models. The software is being developed using the Visual C.NET platform with a graphical user interface (GUI) designed to allow a user to specify the patient type, body scan region, and scanner operating parameters. Using the object-oriented programming technology, 3D phantoms are displayed interactively to improve the user interaction with software functions. The organ dose and effective dose are rapidly archived and reported in the software according to the user-specified protocols. (authors)

  1. Imaging of aortopulmonary collateral arteries with high-resolution multidetector CT

    Energy Technology Data Exchange (ETDEWEB)

    Greil, Gerald F.; Hofbeck, Michael; Sieverding, Ludger [University of Tuebingen, Department of Pediatric Cardiology, Children' s Hospital, Tuebingen (Germany); Schoebinger, Max; Meinzer, Hans-Peter [German Cancer Research Center, Division of Medical and Biological Informatics, Heidelberg (Germany); Kuettner, Axel; Schaefer, Juergen F.; Dammann, Florian; Claussen, Claus D. [University of Tuebingen, Department of Diagnostic Radiology, Tuebingen (Germany)

    2006-06-15

    Precise visualization of the pulmonary vasculature is mandatory for adequate treatment of patients with pulmonary atresia and ventricular septal defect (PA-VSD). Aortopulmonary collateral arteries (APCs) can be visualized by selective injections of contrast agent in the catheterization laboratory. To evaluate multidetector CT (MDCT) and different image postprocessing methods for analysis of complex pulmonary blood supply in patients with PA-VSD. Eight patients (6 weeks to 27.8 years of age) with PA-VSD and APCs underwent MDCT and cardiac catheterization. Using multiplanar reformatting, volume rendering and semiautomatic segmentation algorithms, the aorta, pulmonary arteries and APCs were displayed. MDCT and cardiac catheterization were analyzed by two independent observers. MDCT accurately imaged central pulmonary arteries (n=8), aortopulmonary shunts (n=2), right ventricular to pulmonary artery conduits (n=2) and origin, course and intrapulmonary connections of APCs (n=25), compared to X-ray angiography. A high correlation was found between the MDCT vessel diameter measurements by two independent observers (n=70, r=0.96, P<0.01) and between MDCT and angiographic vessel diameter measurements (n=68, r=0.96, P<0.01). Using three-dimensional imaging software, a complex pulmonary blood supply can be non-invasively and accurately imaged with high-resolution MDCT. This technique may help to reduce the number of cardiac catheterizations or guide interventional or surgical therapy. (orig.)

  2. Temporal bone trauma and the role of multidetector CT in the emergency department.

    Science.gov (United States)

    Zayas, Julio O; Feliciano, Yara Z; Hadley, Celene R; Gomez, Angel A; Vidal, Jorge A

    2011-10-01

    The temporal bone anatomy is complex, with many critical structures in close association with one another. The temporal bone region comprises cranial nerves V, VI, VII, and VIII; vascular structures such as the internal carotid and middle meningeal arteries; sigmoid sinus; jugular bulb; and sensorineural and membranous structures of the inner ear. Most temporal bone fractures are a result of high-energy blunt head trauma. Multidetector computed tomography (CT) plays a fundamental role in the initial evaluation of patients with polytrauma in the emergency department. Multidetector CT may help identify important structural injuries that may have devastating complications such as sensorineural hearing loss, conductive hearing loss, dizziness and balance dysfunction, perilymphatic fistulas, cerebrospinal fluid leaks, facial nerve paralysis, and vascular injury. Although classifying temporal bone fractures helps physicians understand and predict trauma-associated complications and guide treatment, identifying injury to critical structures is more important for guiding management and determining prognosis than is simply classifying temporal bone fractures into a general category. Many temporal bone fractures and complications may be readily identified and characterized at routine cervical, maxillofacial, and head multidetector CT performed in patients with polytrauma, without the need for dedicated temporal bone multidetector CT. Dedicated temporal bone multidetector CT should be considered when there is a high degree of suspicion for temporal bone fractures and no fractures are identified at head, cervical, or maxillofacial CT. PMID:21997992

  3. Multidetector row-CT in evaluation of living renal donors

    Institute of Scientific and Technical Information of China (English)

    ZHANG Ji-qing; HU Xiao-peng; WANG Wei; LI Xiao-bei; YIN Hang; ZHANG Xiao-dong

    2010-01-01

    Background Multidetector-row CT (MDCT) has been evolving to the standard evaluating method of potential living donor in most centers, and can provide excellent details for selecting candidates and determining surgical technique.This study aimed to assess the value of MDCT in evaluation of the anatomy of living kidney donors and to reveal the prevalence of renal vascular variations in a Chinese population.Methods One hundred and four potential donors underwent MDCT and the data sets were post-processed for reformatted images with various techniques, such as maximum intensity projection (MIP), a volume-rendering technique (VR), and multiplanar reformation (MPR). Donor nephrectomies were performed on 97 candidates after MDCT evaluation with the findings during surgery constituting the standard of reference. Resulting MDCT images were compared with actual anatomy found during surgery. Results The MDCT images accurately displayed the anatomic structure of the main renal arteries and veins as well as the upper ureters, except in one case with horseshoe kidney. The prevalence of accessory arteries revealed in images was 27.2% (28/103) and early branching was found in 12.6% (13/103). Compared with findings during surgery, the detection of accessory arteries in MDCT images was 85.7% (6/7), and the detection of larger accessory arteries (>1.5 mm in diameter) was 100%. Detection of early branching was 100%.Conclusion MDCT helps accurately evaluate the renal anatomy of potential donors thus facilitating the planning of surgery.

  4. Guideline for appropriate use of cardiac CT in heart disease

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Young Jin; Hong, Yoo Jin [Dept. of Radiology, Severance Hospital, Yonsei University College of Medicine, Seoul (Korea, Republic of); Yong, Hwan Seok [Dept. of Radiology, Korea University Guro Hospital, Korea University College of Medicine, Seoul (Korea, Republic of); Kim, Sung Mok [Dept. of Radiology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of); Kim, Jeong A [Dept. of Radiology, Ilsan Paik Hospital, Inje University College of Medicine, Goyang (Korea, Republic of); Yang, Dong Hyun [Dept. of Radiology, Asan Medical Center, University of Ulsan College of Medicine, Seoul (Korea, Republic of)

    2014-02-15

    Heart disease is one of the leading causes of deaths in Korea, along with malignant neoplasms and cerebrovascular diseases. The proper diagnosis and management for patients with suspected heart diseases should be warranted for the public health care. Advances in CT technology have allowed detailed images of the heart to be obtained, which enable evaluations not only of the coronary arteries but also of other cardiac structures. Currently, the latest multi-detector CT machines are widespread around Korea. The appropriate use of cardiac CT may lead to improvements of the physicians' medical performances and to reduce medical costs which eventually contribute to promotions of public health. However, until now, there has been no guidelines regarding the appropriate use of cardiac CT in Korea. We intend to provide guidelines for the appropriate use of cardiac CT in heart diseases based on scientific data. The purpose of this guideline is to assist the clinicians and other health professionals when using cardiac CT for diagnosis and treatments of heart diseases.

  5. Application of multi-detector row helical scanning to postmyelographic CT

    International Nuclear Information System (INIS)

    The advent of a multi-detector row helical CT has made it possible to attain images over a broader area with good spatial resolution. We assessed whether postmyelographic CT scans obtained using this system provided more information than conventional imaging techniques. Postmyelographic CT scans were preoperatively obtained in 46 patients using a multi-detector row helical CT system. Reconstructed images in the sagittal and coronal planes in all patients and curved reformation images along the dural sac in 37 patients were compared with myelograms and conventional postmyelographic CT scans. In 34 patients comparison was also made with MR images. The multi-detector row CT images demonstrated deformities of the dural sac more clearly than the other modalities in 39 of the 46 patients. They also provided the best visualization of nerve root abnormalities in 24 of the 46 patients and clearly revealed the presence of spurs in all 22 patients with spinal canal stenosis. Postmyelographic CT scans made using a multi-detector row helical CT system provide more information on the dural sac, nerve sleeves, and their contents than other imaging techniques. (orig.)

  6. Acute aortic syndromes: Role of multi-detector row CT

    Energy Technology Data Exchange (ETDEWEB)

    Salvolini, Luca; Renda, Pietro [Department of Radiology, University ' Politecnica delle Marche' , Ancona (Italy); Fiore, Davide [Department of Radiology, University of Padova, Padova (Italy); Scaglione, Mariano [Emergency and Trauma CT Section, Department of Radiology, Cardarelli Hospital, Naples (Italy); Piccoli, GianPiero [Cardiosurgery Division, Ospedali Riuniti ' Torrette-Lancisi-Salesi' , Ancona (Italy); Giovagnoni, Andrea [Department of Radiology, University ' Politecnica delle Marche' , Ancona (Italy)], E-mail: a.giovagnoni@univpm.it

    2008-03-15

    Acute thoracic aortic syndromes encompass a spectrum of emergencies including aortic dissection, intramural haematoma, penetrating atherosclerotic ulcer and aneurysm rupture. All these life-threatening conditions require prompt diagnosis and appropriate management. To date multi-detector row Computed Tomography represents a valuable diagnostic tool especially in the emergency setting. This paper focus on the use of multi-detector row Computed Tomography in the evaluation of acute thoracic aortic syndromes and illustrates the key imaging findings related to each disease.

  7. Use of multidetector row CT with volume renderings in right lobe living liver transplantation

    International Nuclear Information System (INIS)

    Multidetector row CT is a feasible diagnostic tool in pre- and postoperative liver partial transplantation. We can assess vascular anatomy and liver parenchyma as well as volumetry, which provide useful information for both donor selection and surgical planning. Disorders of the vascular and biliary systems are carefully observed in recipients. In addition, we evaluate liver regeneration of both the donor and the recipient by serial volumetry. We present how multidetector row CT with state-of-the-art three-dimensional volume renderings may be used in right lobe liver transplantation. (orig.)

  8. Multidetector row CT study of percutaneous transhepatic intrahepatic portosystemic shunt

    International Nuclear Information System (INIS)

    Objective: To investigate imaging features of the liver, portal vein and hepatic vein or transhepatic inferior vena cava in patients with severe liver cirrhosis in multidetector row computed tomography (MDCT), and assess the feasibility, safety and clinical significance of percutaneous transhepatic intrahepatic portosystemic, shunt (PTIPS). Methods: Fifty patients with severe liver cirrhosis confirmed by clinical data and imaging examination were enrolled in this study. Simulation of intrahepatic portosystemic shunt by percutaneous transhepatic, approach is as follows. The right midaxillary line (the eighth oi ninth intercostal space) was selected as puncture point A the right branch of portal vein was puncture point B, transhepatic inferior vena cava was puncture point C, and the distal part of right portal vein was D. A-B-C connection is simulated as percutaneous transhepatic puncture tract, C-B-D connection is simulated as portosystemic shunt tract. After tri-phase contrast-enhanced CT scanning, postprocessing images through multiple planner reconstruction (MPR) were obtained. The data were indicated statistically by x-bar±s. And 9.5% confidence interval for mean was calculated. Anatomic relationship among the right portal vein, transhepatic inferior vena cava, hepatic artery and bile duct were analyzed for all patients. Results: The length of the needle (A-B-C) is (145.7±14.8) mm. The curvature of the needle (the angle of A-B line and B-C line) is (145.0±9.9) . The length of transhepatic shunt tract (B-C) is (42.7±7.2) mm. The length of the shunt tract (C-B-D) is (117.7±11.6) mm; The angle of the shunt tract (the angle of B-C line and B-D line) is (108.5±5.9)°. In 24/50 patients, transhepatic inferior vena cava locate in the dorsal of the right portal vein, in 26/50 patients they are in the same plane. In all patients, the right branches of hepatic artery and bile duct locate in the ventral of the right portal vein. Conclusion: The procedure of PTIPS is

  9. Correlation between Acute Coronary Syndrome Classification and Multi-detector CT Characterization of Plaque

    Institute of Scientific and Technical Information of China (English)

    Zhi-guo Wang; Lu-yue Gai; Jing-jing Gai; Ping Li; Xia Yang; Qin-hua Jin; Yun-dai Chen; Zhi-jun Sun; Zhi-wei Guan

    2011-01-01

    Objective To determine if multi-detector CT (MDCT) characterization of plaque is correlated with the classification of acute coronary syndrome (ACS). Methods Altogether 1900 patients were examined by MDCT from December 2007 to May 2009,of whom 95 patients fulfilled the criteria of ACS. Those patients were divided into the discrete plaque group (n=61) and diffuse plaque group (n=34) based on the findings in MDCT. The clinical diagnosis of ACS and CT results were analyzed, including segment stenosis score, segment involvement score, 3-vessel plaque score, left main score, calcification score, and remodeling index. The incidences of major adverse cardiac events in follow-up period were also recorded.Results The patients of the diffuse plaque group were older than those of the discrete plaque group (P<0.0001). The diffuse plaque group presented more cases of hypertension, peripheral artery disease, diabetes, and heart failure than discrete plaque group (all P<0.05). All the 5 patients with ST-segment elevation myocardial infarction were found in discrete plaque group. The segment stenosis score of the discrete plaque group was lower than that of the diffuse plaque group (5.15+3.55 vs. 14.91+5.37, P<0.001). The other four scores demonstrated significant inter-group difference as well (all P<0.05). The remodeling index of the discrete plaque group was higher (1.12+0.16 vs. 0.97+0.20, P<0.05). Follow-up data showed that major adverse cardiac events occurred more frequently in diffuse plaque group than in discrete group (29.41% vs.11.48%, P=0.0288).Conclusions Characteristics of discrete and diffuse plaques may be significandy different among different classes of ACS. The diffuse plaque may present higher risk, correlated to higher mortality. The diagnosis of discrete and diffuse plaques by MDCT would provide a new insight into the prognosis and treatment of ACS.

  10. Evaluation of secondary spontaneous pneumothorax with multidetector CT

    International Nuclear Information System (INIS)

    The purpose of this article is to review the underlying causes of secondary pneumothoraces as observed on multidetector computed tomography (MDCT). Using examples from our institutional experience, we shall illustrate important diagnostic features to indicate the underlying lung disease. Understanding the varied range of conditions is important for accurate diagnosis and facilitation of patient management

  11. Pancreatic pseudoaneurysm in a child with hereditary pancreatitis: diagnosis with multidetector CT angiography

    International Nuclear Information System (INIS)

    Pseudoaneurysm formation is a serious vascular complication of pancreatitis. It most commonly affects splenic and gastroduodenal arteries. We report a rare case of superior mesenteric artery pseudoaneurysm in a child with hereditary pancreatitis. Multidetector CT angiography allowed the comprehensive assessment of the aneurysm and allowed accurate surgical planning obviating the need for catheter angiography. (orig.)

  12. Deepgoing study on intrathoracic tuberculous lymphadenitis in adults using multidetector CT

    Institute of Scientific and Technical Information of China (English)

    LUO Ming-yue; LIU Li; LAI Li-sha; DONG Yun-xu; LIANG Wen-wei; QIN Jie

    2010-01-01

    Background Studies on intrathoracic tuberculous lymphadenitis in adults are confined to the preliminary CT findings with ordinary CT and ordinary spiral CT.There has been no deepgoing study of multidetector CT to date.Multidetector CT could contribute to better imaging of intrathoracic tuberculous lymphadenitis in adults.The purpose of this study was to explore the multidetector CT features of intrathoracic tuberculous lymphadenitis in adults, and the correlation with clinical symptoms and pathologic changes.Methods Multidetector CT findings from 42 consecutive adult patients with intrathoracic tuberculous lymphadenitis were analyzed retrospectively with regard to locations, sizes, numbers, shapes, margins, and densities reviewing precontrast and enhanced images.CT results were correlated with clinical symptoms and pathologic results (n=37).Results One hundred and eighty-five intrathoracic lymph nodes that had tuberculous lymphadenitis in 42 patients were distributed mainly in regions 4R (n=37), 2R (n=33), 7 (n=31) and 10R (n=21), more than 2 regions were implicated in 34 patients.One hundred and twenty-two (72.2%) of the tuberculous lymphadenitis without confluence were oval or round with clear margins.On precontrast scanning, 78.4% of tuberculous lymphadenitis had a homogeneous density.Seven enhancement patterns were demonstrated in 169 tuberculous lymphadenitis from 37 patients with pathologic results:homogeneous enhancement with no clinical symptom (n=12), corresponded pathologically to tuberculous hyperplasia without caseous necrosis; heterogeneous enhancement with a small central no enhancement area, slight clinical symptoms (n=22), tuberculous granulomas with a little caseous necroses; peripheral irregular thick wall enhancement with a central area with no enhancement, slight clinical symptoms (n=52), tuberculous granulomas with some caseous necroses in the center; peripheral thin rim enhancement with a central area having no enhancement, moderate clinical

  13. Detection of Postcoronary Stent Complication: Utility of 64-Slice Multidetector CT

    Directory of Open Access Journals (Sweden)

    Alpa Bharati

    2012-01-01

    Full Text Available Coronary stent fracture is a known complication of coronary arterial stent placements. Multiple long-term risks are also associated with drug eluting stents. 64-slice multidetector CT (MDCT coronary angiography has been shown to detect poststent complications such as instent stenosis, thrombosis, stent migration and stent fractures. We report a case of stent fracture in a patient who underwent RCA stenting with associated RCA perforation and almost complete thrombosis of the RCA and peristent fibrinoid collection. This is a rare case of stent fracture with perforation of the RCA. The paper highlights the role of 64-row multidetector computed tomography (MDCT in evaluation of such poststent placement complications.

  14. Advances in multidetector CT diagnosis of pediatric pulmonary thromboembolism

    Energy Technology Data Exchange (ETDEWEB)

    Thacker, Paul G. [Dept. of Radiology and Radiological Science, Medical University of South Carolina, Charleston (United States); Lee, Edward Y. [Divi. of Thoracic Imaging, Dept. of Radiology and Medicine, Pulmonary Division Boston Children' s Hospital, Harvard Medical School, Boston (United States)

    2016-04-15

    Although pediatric pulmonary thromboembolism is historically believed to be rare with relatively little information available in the medical literature regarding its imaging evaluation, it is more common than previously thought. Thus, it is imperative for radiologists to be aware of the most recent advances in its imaging information, particularly multidetector computed tomography (MDCT), the imaging modality of choice in the pediatric population. The overarching goal of this article is to review the most recent updates on MDCT diagnosis of pediatric pulmonary thromboembolism.

  15. Diagnostic accuracy of 64-slice multidetector CT for detection of in-stent restenosis in an unselected, consecutive patient population

    Energy Technology Data Exchange (ETDEWEB)

    Haraldsdottir, Sigurdis, E-mail: sigurdisha@gmail.com [Boston Medical Center, 72 East Concord Street (Evans 124), Boston, MA, 02118 (United States); Gudnason, Thorarinn, E-mail: thorgudn@landspitali.is [Landspitali University Hospital, Hringbraut, 101 Reykjavik (Iceland); Sigurdsson, Axel F., E-mail: axelfsig@landspitali.is [Landspitali University Hospital, Hringbraut, 101 Reykjavik (Iceland); Gudjonsdottir, Jonina, E-mail: jonina@rd.is [Rontgen Domus Medica, Egilsgata 3, 101 Reykjavik (Iceland); Lehman, Sam J., E-mail: slehman@partners.org [Massachusetts General Hospital, 165 Cambridge Street, Suite 400, Boston, MA 02114 (United States); Eyjolfsson, Kristjan, E-mail: kristey@landspitali.is [Landspitali University Hospital, Hringbraut, 101 Reykjavik (Iceland); Scheving, Sigurpall S., E-mail: sigurpal@landspitali.is [Landspitali University Hospital, Hringbraut, 101 Reykjavik (Iceland); Gibson, C. Michael, E-mail: mgibson@perfuse.org [Beth Israel Deaconess Medical Center, 330 Brookline Avenue, Boston, MA 02115 (United States); Hoffmann, Udo, E-mail: uhoffmann@partners.org [Massachusetts General Hospital, 165 Cambridge Street, Suite 400, Boston, MA 02114 (United States); Jonsdottir, Birna, E-mail: birna@rd.is [Rontgen Domus Medica, Egilsgata 3, 101 Reykjavik (Iceland); Andersen, Karl, E-mail: andersen@landspitali.is [Landspitali University Hospital, Hringbraut, 101 Reykjavik (Iceland)

    2010-11-15

    Objectives: To investigate the diagnostic accuracy of 64-slice multidetector computed tomography (64-CT) for detection of in-stent restenosis (ISR) in an unselected, consecutive patient population. Background: Detection of in-stent restenosis by cardiac CT would be a major advance for the evaluation of patients suspected of having ISR. However, the diagnostic accuracy of current generation 64-CT in this context is not fully established. Methods: We conducted a prospective study on patients with stable angina or acute coronary syndrome with no prior history of coronary artery disease. Six months after percutaneous coronary intervention (PCI) with stent placement they underwent a 64-CT scan (Toshiba Multi-Slice Aquilion 64) and consequently a repeat coronary angiography for comparison. Cardiac CT data sets were analyzed for the presence of in-stent restenosis by two independent expert readers blinded to the coronary angiographic data. Results: Ninety-three patients with a total of 140 stents were evaluated. Males comprised 82% of the study group and the mean age was 63 {+-} 10 years. The mean time from PCI to the repeat coronary angiography was 208 {+-} 37 days and the mean time from 64-CT to repeat coronary angiography was 3.7 {+-} 4.9 days. The restenosis rate according to coronary angiography was 26%. Stent diameter, strut thickness, heart rate and body mass index (BMI) significantly affected image quality. The sensitivity, specificity, positive and negative predictive values of 64-CT for detection of in-stent restenosis were 27%, 95%, 67% and 78%, respectively. Conclusions: Current generation, 64-slice CT, remains limited in its ability to accurately detect in-stent restenosis.

  16. Coronary artery imaging during preoperative CT staging: preliminary experience with 64-slice multidetector CT in 99 consecutive patients

    Energy Technology Data Exchange (ETDEWEB)

    Delhaye, Damien; Remy-Jardin, Martine; Rozel, Celine; Remy, Jacques [University Center of Lille, Boulevard Jules Leclerc, Department of Thoracic Imaging, Hospital Calmette, Lille cedex (France); Dusson, Catherine; Wurtz, Alain [University Center of Lille, Department of Thoracic Surgery, Hospital Calmette, Lille cedex (France); Delannoy-Deken, Valerie; Duhamel, Alain [University of Lille, Department of Medical Statistics, Lille cedex (France)

    2007-03-15

    The purpose of this study was to evaluate the clinical feasibility of coronary artery imaging during routine preoperative 64-slice MDCT scans of the chest. Ninety-nine consecutive patients in sinus rhythm underwent a biphasic multidetector-row spiral CT examination of the chest without the administration of beta-blockers, including an ECG-gated acquisition over the cardiac cavities, followed by a non-gated examination of the upper third of the thorax. Data were reconstructed to evaluate coronary arteries and to obtain presurgical staging of the underlying disease. The percentage of assessable segments ranged from 65.4% (972/1,485) when considering all coronary artery segments to 88% (613/693) for the proximal and mid segments, reaching 98% (387/396) for proximal coronary artery segments. The 387 interpretable proximal segments included 97 (97%) LM, 99 (100%) LAD, 96 (97%) LCX and 95 (96%) RCA with a mean attenuation of 280.70{+-}52.93 HU. The mean percentage of assessable segments was significantly higher in patients with a heart rate {<=}80 bpm (n=48) than in patients with a heart rate greater than 80 bpm (n=35) (80{+-}11% vs. 72{+-}13%; P=0.0008). Diagnostic image quality was achieved in all patients for preoperative staging of the underlying disorder. The mean estimated effective dose was 12.06{+-}3.25 mSv for ECG-gated scans and 13.88{+-}3.49 mSv for complete chest examinations. Proximal and mid-coronary artery segments can be adequately evaluated during presurgical CT examinations of the chest obtained with 64-slice MDCT without the administration of {beta}-blockers. (orig.)

  17. The Utility of 64 Channel Multidetector CT Angiography for Evaluating the Renal Vascular Anatomy and Possible Variations: a Pictorial Essay

    International Nuclear Information System (INIS)

    The increased use of laparoscopic nephrectomy and nephron-sparing surgery has prompted the need for a more detailed radiological evaluation of the renal vascular anatomy. Multidetector CT angiography is a fast and accurate modality for assessing the precise anatomy of the renal vessels. In this pictorial review, we present the multidetector CT angiography appearances of the normal renal vascular anatomy and a spectrum of various anomalies that require accurate vascular depiction before undergoing surgical treatment

  18. Detectability of the appendix with multidetector-row CT scanning and multiplanar reconstruction

    International Nuclear Information System (INIS)

    Twenty-six consecutive patients with the clinical diagnosis of appendicitis underwent multidetector-row CT (MD-CT) in order to detect entire longitudinal configuration of the appendix. While axial CT failed to detect the appendix in 7 patients, multiplanar reconstruction (MPR) demonstrated a longitudinal tubular structure continuous from the cecal caput in 25 patients (96.2%), including 7 patients whose post-surgical pathology were available. It is summarized that scanning and MPR images are advantageous to finding inflammatory processes in the appendix when the diagnosis of appendicitis remains ambiguous even with US. (author)

  19. Multidetector CT (MD-CT) in the diagnosis of uncertain open globe injuries

    Energy Technology Data Exchange (ETDEWEB)

    Hoffstetter, P.; Schreyer, A.G.; Jung, E.M.; Heiss, P.; Zorger, N. [Inst. fuer Roentgendiagnostik, Universitaetsklinikum Regensburg (Germany); Schreyer, C.I.; Framme, C. [Klink und Poliklinik fuer Augenheilkunde, Universitaetsklinikum Regensburg (Germany)

    2010-02-15

    Purpose: To evaluate the significance of multislice CT for the diagnosis of uncertain penetrating globe injuries. Materials and Methods: Based on a retrospective chart review between 2002 and 2007, we identified 59 patients presenting with severe ocular trauma with uncertain rupture of the globe due to massive subconjunctival and/or anterior chamber hemorrhage. The IOP (intraocular pressure) was within normal range in all patients. High resolution multidetector CT (MD-CT) scans (16 slice scans) with axial and coronar reconstructions were performed in all patients. The affected eye was examined for signs of penetrating injury such as abnormal eye shape, scleral irregularities, lens dislocation or intravitreal hemorrhages. Four experienced radiologists read the CT scans independently. Beside the diagnosis, the relevant morphological criteria and the optimal plane orientation (axial or coronar) were specified. The sensitivity, specificity, and negative and positive predictive value were calculated. Additionally the interobserver variability was determined by applying the Cohen's kappa test. Surgical sclera inspections were performed in all cases as a standard of reference. The evaluations of the CT examination were compared with the surgery reports. Results: 59 patients were evaluated (42 men, 17 women). The mean age was 29 years (range 7-91). In 17 patients a rupture of the globe was diagnosed during surgery. 12 of these 17 penetrating injuries (70.6%) were classified correctly by MDCT, 5 of the 17 (29.4%) were not detectable. 42 patients did not have an open globe injury. 41 of these patients were diagnosed correctly negative by MDCT, and one patient was classified false positive. This results in a sensitivity of 70% with a specificity of 98%. There was high inter-rater agreement with kappa values between 0.89-0.96. Most discrepancies were caused by wrong negative findings. The most frequent morphologic criteria for open globe injury were the deformation (n

  20. Comparative evaluation of multidetector CT and MR imaging in the differentiation of adnexal masses

    International Nuclear Information System (INIS)

    The purpose was to compare the accuracy of multidetector CT (MDCT) on a 16-row CT scanner and magnetic resonance (MR) imaging in the characterization of ovarian masses. Preoperative CT examination of the abdomen and MR imaging of the pelvis was performed in 67 women, with clinically or sonographically detected adnexal masses. The CT examinations were performed on a 16-row CT scanner, and the protocol included scanning of the abdomen during the portal phase, using a detector collimation of 16 x 0.75 mm and a pitch of 1.2. We used a 1.5-T magnet unit to perform T1, T2 and fat-suppressed T1-weighted sequences, before and after intravenous administration of gadolinium chelate compounds. The accuracy of multidetector CT and MR imaging in the differentiation between benign and malignant ovarian masses was evaluated, using histopathologic results as the standard of reference. The sensitivity, specificity and accuracy of MDCT in the characterization of ovarian masses were 90.5%, 93.7% and 92.9%, respectively, and that of MR imaging 95.2%, 98.4% and 97.6%, respectively. Although MRI performed slightly better, this did not reach statistical significance. In conclusion, both MDCT on a 16-row CT scanner and MR imaging demonstrated satisfactory results in the characterization of ovarian masses. (orig.)

  1. Blind-ending branch of a bifid ureter: multidetector CT imaging findings

    Science.gov (United States)

    Chang, E; Santillan, C; O'Boyle, M K

    2011-01-01

    A bifid ureter with a blind-ending branch is a rare congenital anomaly. Although typically found incidentally, this anomaly can be symptomatic and radiologists should be aware of this important variant. To our knowledge, there has been no previous report of this anomaly as seen on multidetector CT urography. We present a patient with haematuria and review the clinical significance, radiological findings and embryological aetiology of this anomaly. PMID:21257834

  2. Diagnosis of arterioportal shunts in cases of hepatocellular carcinoma using multidetector CT: Impact on clinical management

    OpenAIRE

    Ahmed Mostafa Mohamed; Mohamed El Gharib A. Elmaaty; Ayman Mohamed Ibrahim; Waleed Hamed; Amr Hafez El Fouly

    2014-01-01

    Purpose: To study the ability of multidetector CT (MDCT) to diagnose arterioportal shunts (APS) associated with hepatocellular carcinoma (HCC) and its impact on further management of the patient. Patients and methods: 252 Patients with HCC were examined by triphasic MDCT scanning. Images were analyzed for the presence, locations, types and degrees of APS, being with or without thrombosis. Digital subtraction angiographies (DSA) were performed for 22 patients as a part of further therapeuti...

  3. Multidetector CT angiography of renal vasculature: normal anatomy and variants

    Energy Technology Data Exchange (ETDEWEB)

    Tuerkvatan, Aysel; Oezdemir, Mustafa; Cumhur, Turhan; Oelcer, Tuelay [Tuerkiye Yueksek ihtisas Hospital, Department of Radiology, Sihhiye, Ankara (Turkey)

    2009-01-15

    Knowledge of the variations in renal vascular anatomy is important before laparoscopic donor or partial nephrectomy and vascular reconstruction for renal artery stenosis or abdominal aortic aneurysm. Recently, multidetector computed tomographic (MDCT) angiography has become a principal imaging investigation for assessment of the renal vasculature and has challenged the role of conventional angiography. It is an excellent imaging technique because it is a fast and non-invasive tool that provides highly accurate and detailed evaluation of normal renal vascular anatomy and variants. The number, size and course of the renal arteries and veins are easily identified by MDCT angiography. The purpose of this pictorial essay is to illustrate MDCT angiographic appearance of normal anatomy and common variants of the renal vasculature. (orig.)

  4. Acute mediastinitis: multidetector computed tomography findings following cardiac surgery

    Energy Technology Data Exchange (ETDEWEB)

    Macedo, Clarissa Aguiar de [Universidade de Sao Paulo (USP), SP (Brazil). Faculdade de Medicina. Instituto do Coracao (InCor)]. E-mail: clarissaaguiarm@yahoo.com.br; Baena, Marcos Eduardo da Silva [Instituto do Coracao (InCor), Sao Paulo, SP (Brazil). Unit of Ultrasonography; Uezumi, Kiyomi Kato [Instituto do Coracao (InCor), Sao Paulo, SP (Brazil). Unit of Computed Tomography; Castro, Claudio Campi de [Instituto do Coracao (InCor), Sao Paulo, SP (Brazil). Unit of Magnetic Resonance Imaging; Lucarelli, Claudio Luiz [Instituto do Coracao (InCor), Sao Paulo, SP (Brazil). Center of Diagnosis; Cerri, Giovanni Guido [Universidade de Sao Paulo (USP), SP (Brazil). School of Medicine. Dept. of Radiology

    2008-07-15

    Postoperative mediastinitis is defined as an infection of the organs and tissues in the mediastinal space, with an incidence ranging between 0.4% and 5% of cases. This disease severity varies from infection of superficial tissues in the chest wall to fulminant mediastinitis with sternal involvement. Diagnostic criterion for postoperative detection of acute mediastinitis at computed tomography is the presence of fluid collections and gas in the mediastinal space, which might or might not be associated with peristernal abnormalities such as edema of soft tissues, separation of sternal segments with marginal bone resorption, sclerosis and osteomyelitis. Other associated findings include lymphadenomegaly, pulmonary consolidation and pleural/ pericardial effusion. Some of these findings, such as mediastinal gas and small fluid collections can be typically found in the absence of infection, early in the period following thoracic surgery where the effectiveness of computed tomography is limited. After approximately two weeks, computed tomography achieves almost 100% sensitivity and specificity. Patients with clinical suspicion of mediastinitis should be submitted to computed tomography for investigating the presence of fluid collections to identify the extent and nature of the disease. Multidetector computed tomography allows 3D images reconstruction, contributing particularly to the evaluation of the sternum. (author)

  5. The Role of Multidetector CT in the Diagnosis of Retroperitoneal Fibrosis: Report of a Case

    International Nuclear Information System (INIS)

    Herein, we report a 40-year old man who presented with flank and abdominal pain with dilatation of the bilateral pyelocalyceal system detected in ultrasonography. Computed Tomography (CT) scan showed a soft tissue mass at the level of the fourth and fifth lumbar vertebrae in the retroperitoneal region. There were no blood flow signals in 64-slice multidetector CT (MDCT) which confirms the Retroperitoneal Fibrosis (RPF). Pathological examination showed infiltration of plasma cells, macrophages, lymphocytes and eosinophils accompanied by fibrosis, which is consistent with idiopathic RPF. In conclusion, 64-slice MDCT imaging is useful in the diagnosis of RPF

  6. Multi-detector CT imaging in the postoperative orthopedic patient with metal hardware

    Energy Technology Data Exchange (ETDEWEB)

    Vande Berg, Bruno [Department of Radiology, Cliniques Universitaires Saint-Luc, 10 Avenue Hippocrate, 1200 Brussels (Belgium)]. E-mail: vandeberg@rdgn.ucl.ac.be; Malghem, Jacques [Department of Radiology, Cliniques Universitaires Saint-Luc, 10 Avenue Hippocrate, 1200 Brussels (Belgium); Maldague, Baudouin [Department of Radiology, Cliniques Universitaires Saint-Luc, 10 Avenue Hippocrate, 1200 Brussels (Belgium); Lecouvet, Frederic [Department of Radiology, Cliniques Universitaires Saint-Luc, 10 Avenue Hippocrate, 1200 Brussels (Belgium)

    2006-12-15

    Multi-detector CT imaging (MDCT) becomes routine imaging modality in the assessment of the postoperative orthopedic patients with metallic instrumentation that degrades image quality at MR imaging. This article reviews the physical basis and CT appearance of such metal-related artifacts. It also addresses the clinical value of MDCT in postoperative orthopedic patients with emphasis on fracture healing, spinal fusion or arthrodesis, and joint replacement. MDCT imaging shows limitations in the assessment of the bone marrow cavity and of the soft tissues for which MR imaging remains the imaging modality of choice despite metal-related anatomic distortions and signal alteration.

  7. Evaluation of tracheal bronchus in Chinese children using multidetector CT

    Energy Technology Data Exchange (ETDEWEB)

    Ming, Zhu; Lin, Zhang [Shanghai Children' s Medical Center, Department of Radiology, Shanghai (China)

    2007-12-15

    Tracheal bronchus is a congenital bronchial anomaly. The diagnosis should be considered early in intubated patients. Multidetector computed tomography (MDCT) is the newest modality for evaluating tracheal bronchus. To evaluate the utility of 16-slice MDCT in children with tracheal bronchus and to characterize the frequency of tracheal bronchus in children with congenital heart disease. From June 2005 to May 2007, 3,187 consecutive children (1,124 with congenital heart disease and 2,063 without congenital heart disease) underwent MDCT examination. Minimum-intensity projection reconstruction was performed to show the tracheobronchial tree in every case. Tracheal bronchus was found in 42 children (3.74%) with congenital heart disease but in only 6 children (0.29%) without congenital heart disease. Among the 48 children with tracheal bronchus, 45 had right-side tracheal bronchus and 3 had bilateral tracheal bronchi with heterotaxy syndrome. The diagnostic sensitivity of MDCT was 100% (48/48). MDCT is a reliable imaging technique for the diagnosis of tracheal bronchus. Our data showed that right-side tracheal bronchus was more common and bilateral tracheal bronchi usually occurred with heterotaxy syndrome. In addition, tracheal bronchus often occurred with congenital heart disease. The angle between the tracheal bronchus and the trachea is important and should be measured. (orig.)

  8. Value of three-dimensional reconstructions in pancreatic carcinoma using multidetector CT: Initial results

    Institute of Scientific and Technical Information of China (English)

    Miriam Klauβ; Max Sch(o)binger; Ivo Wolf; Jens Werner; Hans-Peter Meinzer; Hans-Ulrich Kauczor; Lars Grenacher

    2009-01-01

    AIM: To evaluate the use of three-dimensional imaging of pancreatic carcinoma using multidetector computed tomography (CT) in a prospective study. METHODS: Ten patients with suspected pancreatic tumors were examined prospectively using multidetector CT (Somatom Sensation 16, Siemens, Erlangen, Germany). The images were evaluated for the presence of a pancreatic carcinoma and invasion of the peripancreatic vessels and surrounding organs. Using the isotropic CT data sets, a three-dimensional image was created with automatic vascular analysis and semiautomatic segmentation of the organs and pancreatic tumor by a radiologist. The CT examinations and the three-dimensional images were presented to the surgeon directly before and during the patient's operation using the Medical Imaging Interaction Toolkit-based software "ReLiver". Immediately after surgery, the value of the two images was judged by the surgeon. The operation and the histological results served as the gold standard. RESULTS: Nine patients had a pancreatic carcinoma (all pT3), and one patient had a serous cystadenoma. One tumor infiltrated the superior mesenteric vein. The infiltration was correctly evaluated. All carcinomas were resectable. In comparison to the CT image with axial and coronal reconstructions, the three-dimensional image was judged by the surgeons as better for operation planning and consistently described as useful. CONCLUSION: A 3D-image of the pancreas represents an invaluable aid to the surgeon. However, the 3D-software must be further developed in order to be integrated into daily clinical routine.

  9. Data explosion: the challenge of multidetector-row CT

    International Nuclear Information System (INIS)

    The development of multi detector-row CT has brought many exciting advancements to clinical CT scanning. While multi detector-row CT offers unparalleled speed of acquisition, spatial resolution, and anatomic coverage, a challenge presented by these advantages is the substantial increase on the number of reconstructed cross-sections that are rapidly created and in need of analysis. This manuscript discusses currently available alternative visualization techniques for the assessment of volumetric data acquired with multi detector-row CT. Although the current capabilities of 3-D workstations offer many possibilities for alternative analysis of MCDT data, substantial improvements both in automated processing, processing speed and user interface will be necessary to realize the vision of replacing the primary analysis of transverse reconstruction's with alternative analyses. The direction that some of these future developments might take are discussed

  10. Estudio vascular renal por TC multidetector de 64 canales 64-Multidetector row CT for the Renal Vascular Study

    Directory of Open Access Journals (Sweden)

    Daniela Stoisa

    2009-03-01

    Full Text Available Objetivo: Mostrar las diversas variantes anatómicas vasculares tanto arteriales como venosas en el estudio angiográfico renal por tomografìa computada multidetector (TCMD de 64 canales, dada su implicancia en un eventual planeamiento quirúrgico. Material y métodos: Evaluamos retrospectivamente 26 estudios realizados con tomógrafo Philips Brilliance de 64 canales. Se obtuvieron secuencias sin contraste y postcontraste e.v. en fases arterial y venosa, administrado con bomba inyectora doble cabezal. Para una fase arterial apropiada se utilizó técnica de bolus track. Las imágenes fueron posteriormente procesadas en Workstation Philips Brilliance 190P en un tiempo promedio de 30 minutos y reconstruidas con técnicas MIP y volumétrica. Resultados: Dentro de las variantes anatómicas arteriales, encontramos: bifurcaciones prehiliares (n=3, arterias accesorias (n=4 y arterias polares (n=9. Dentro de las variantes venosas fueron halladas: venas renales múltiples (n=5, venas circumaórticas (n=2, retroaórticas (n=2 y vena tributaria lumbar prominente (n=1. Conclusión: El estudio vascular renal adquiere importancia en el planeamiento quirúrgico en casos de nefrectomías parciales, laparoscópicas y en el transplante renal. Esto otorga suma utilidad al estudio de TCMD de 64 canales por su eficacia diagnóstica, dada la alta calidad de las reconstrucciones obtenidas, llegando a igualar a la angiografía digital, sin ser un método invasivo.Purpose: To show the wide range of anatomical vascular variants, arterial and venous, that can be seen in the angiographic renal study using 64-multidetector-row computed tomography (64-MDCT, due to its importance in an eventual surgical planning. Material and Methods: We have evaluated retrospectively 26 studies that have been done using a 64 channels Philips Brilliance CT scanner. We have obtained non enhanced and both in arterial and venous enhanced sequences. For the injection of the contrast material we

  11. Multidetector CT of Mandibular Fractures, Reductions, and Complications: A Clinically Relevant Primer for the Radiologist.

    Science.gov (United States)

    Dreizin, David; Nam, Arthur J; Tirada, Nikki; Levin, Martin D; Stein, Deborah M; Bodanapally, Uttam K; Mirvis, Stuart E; Munera, Felipe

    2016-01-01

    After the nasal bones, the mandible is the second most common site of facial fractures, and mandibular fractures frequently require open reduction. In the trauma injury setting, multidetector computed tomography (CT) has become the cornerstone imaging modality for determining the most appropriate treatment management, fixation method, and surgical approach. Multidetector CT is also used to assess the adequacy of the reduction and evaluate potential complications in the postoperative period. For successful restoration of the mandible's form and function, as well as management of posttraumatic and postoperative complications, reconstructive surgeons are required to have a detailed understanding of mandibular biomechanics, occlusion, and anatomy. To provide added value in the diagnosis, treatment planning, and follow-up of mandibular fractures, radiologists should be aware of these concepts. Knowledge of the techniques commonly used to achieve occlusal and anatomic reduction and of the rationale behind the range of available treatment options for different injury patterns-from isolated and nondisplaced fractures to multisite and comminuted fractures-also is essential. This article focuses on the use of multidetector CT for pre- and postoperative evaluation of mandibular fractures and outlines fundamental concepts of diagnosis and management-beginning with an explanation of common fracture patterns and their biomechanical underpinnings, and followed by a review of the common postoperative appearances of these fractures after semirigid and rigid fixation procedures. Specific considerations regarding fractures in different regions of the tooth-bearing and non-tooth-bearing mandible and the unique issues pertaining to the edentulous atrophic mandible are reviewed, and key features that distinguish major from minor complications are described. (©)RSNA, 2016. PMID:27618328

  12. Multidetector-row CT angiography of hepatic artery: comparison with conventional angiography

    International Nuclear Information System (INIS)

    To determine the usefulness of three-dimensional CT angiography using multidetector-row CT (MD-CT) for delineating the arterial anatomy of the liver. Hepatic arterial three-dimensional CT angiography was performed using MDCT (lightspeed Qx/I; GE medical systems, milwaukee, Wis., U.S.A.) in 45 patients with HCC undergoing conventional angiography for transcatheter hepatic arterial chemoembolization. The scanning parameters during the early arterial phase were 2.5 mm slice thickness, 7.5 mm rotation of table speed, and a pitch of 3. Images were obtained by one radiologist using maximum intensity projection from axial CT images obtained during the early arterial phase. Two radiologists blinded to the findings of conventional angiography independently evaluated the hepatic arterial anatomy and the quality of the images obtained. Compared with conventional angiography, reader A correctly evaluated the hepatic arterial anatomy depicted at three-dimensional CT angiography. Reader B's evaluation was correct in 40 of 45 patients. Interobserver agreement was good (kappa value, 0.73), and both readers assessed the quality of three-dimensional CT angiography as excellent. Three-dimensional CT angiography using MDCT was accurate for delineating the arterial anatomy of the liver, and interobserver agreement was good. The modality may provide, prior to conventional angiography, valuable information regrading a patient's hepatic arterial anatomy

  13. Multidetector CT of expected findings and complications after contemporary inguinal hernia repair surgery

    Science.gov (United States)

    Tonolini, Massimo

    2016-01-01

    Inguinal hernia repair (IHR) with prosthetic mesh implantation is the most common procedure in general surgery, and may be performed using either an open or laparoscopic approach. This paper provides an overview of contemporary tension-free IHR techniques and materials, and illustrates the expected postoperative imaging findings and iatrogenic injuries. Emphasis is placed on multidetector CT, which represents the ideal modality to comprehensively visualize the operated groin region and deeper intra-abdominal structures. CT consistently depicts seroma, mesh infections, hemorrhages, bowel complications and urinary bladder injuries, and thus generally provides a consistent basis for therapeutic choice. Since radiologists are increasingly requested to investigate suspected iatrogenic complications, this paper aims to provide an increased familiarity with early CT studies after IHR, including complications and normal postoperative appearances such as focal pseudolesions, in order to avoid misinterpretation and inappropriate management. PMID:27460285

  14. Significant reduction of left atrial volume concomitant with clinical improvement after percutaneous transluminal septal myocardial ablation for drug-refractory hypertrophic obstructive cardiomyopathy, and its precise detection with multidetector CT

    OpenAIRE

    Maekawa, Yuichiro; Akita, Keitaro; Tsuruta, Hikaru; Yamada, Yoshitake; Hayashida, Kentaro; Yuasa, Shinsuke; Murata, Mitsushige; Jinzaki, Masahiro; Fukuda, Keiichi

    2016-01-01

    Objective In patients with hypertrophic obstructive cardiomyopathy (HOCM), left atrial (LA) volume measurement is very important to provide prognostic information. Recent studies demonstrated that multidetector CT (MDCT) is useful to assess the changes in LA volume. Our aim was to examine the utility of a follow-up cardiac MDCT for long-term evaluation of the effect of percutaneous transluminal septal myocardial ablation (PTSMA) on LA volume. Methods We studied a consecutive cohort of 20 pati...

  15. A single coronary artery with the right coronary artery originating from the left anterior descending artery detected by cardiac CT: A case report

    International Nuclear Information System (INIS)

    The right coronary artery arising from the left anterior descending artery is a rare coronary artery anomaly. In a 56 year old female, an anomaly with the right coronary artery, originating from the left anterior descending artery, coursing anteriorly to the pulmonary artery was detected by cardiac CT. Therefore, we hereby report a case of the single left coronary artery diagnosed by a 64 slice multidetector cardiac CT

  16. Multidetector CT in evaluating blood supply of hepatocellular carcinoma after transcatheter arterial chemoembolization

    Institute of Scientific and Technical Information of China (English)

    Yong-Song Guan; Xiao-Hua Zheng; Xiang-Ping Zhou; Juan Huang; Long Sun; Xian Chen; Xiao Li; Qing He

    2004-01-01

    AIM: To assess the value of multidetector-row computed tomography (MDCT) in choosing retreatment methods of hepatocellular carcinoma (HCC) through evaluating the blood supply of low-density area of HCC after transcatheter arterial chemoembolization (TACE).METHODS: Thirty-two patients with HCC after TACE treatment were examined by plain scanning and hepatic multidetector-row CT. The location of low-density area on plain scanning and the enhancement patterns on dynamic contrast-enhanced scanning were observed. At the same time, three-dimensional CT (3D CT) models of the volume rendering, curved multiplanar reformations, surface shaded display and maximum intensity projection reconstruction of the hepatic artery and portal vein were performed in 6 cases.RESULTS: In CT plain scanning data, low density areas of 32 cases of HCC after TACE treatment were divided into three types: peripheral, one-side-located and mixed types.In contrast-enhanced CT scans, the blood supply of lowdensity area was classified into four types: arterial blood supply (20 cases), portal blood supply (5 cases), arterial combined with portal blood supply (5 cases) and poor blood supply (2 cases). In 6 cases, the relationship between the low-density area and branches of hepatic artery as well as portal vein was shown by 3D CT.CONCLUSION: Hepatic MDCT is an effective method for evaluating the blood supply of low-density area and therapeutic effect of HCC after TACE treatment. Types of blood supply is helpful for the selection of retreatment.

  17. T-staging of gastric cancer of air-filling multidetector-row CT: Comparison with hydro-multidetector-row CT

    International Nuclear Information System (INIS)

    Purpose: The purpose of this study was to evaluate the accuracy of T-staging of gastric cancer by air-filling multidetector-row CT (air-MDCT) compared with water-filling MDCT (hydro-MDCT). Materials and methods: One hundred fifteen patients with histologically diagnosed gastric cancer were included in this study. Fifty-eight patients underwent air-MDCT, and the remaining 57 had hydro-MDCT using a 64-channel scanner. Based on the volumetric data of contrast-enhanced MDCT obtained about 75 s after intravenously injecting 525 mg iodine per kilogram patients weight (525 mgI/kg) nonionic contrast material at the rate of 2 ml/s, oblique coronal and oblique sagittal multi-planar reformatted images perpendicular to the stomach wall, including the tumor, were reconstructed on a workstation. Mural invasion of gastric cancer into the gastric wall, as visualized by CT, was classified according to the TNM classification, and the results of T-staging by MDCT were compared with those by pathologic analysis after surgery. Results: Correct assessment of T-staging by air-CT was achieved in 48 of 58 patients (83%), and that by hydro-MDCT was 49 of 57 patients (86%). The sensitivity, specificity, and accuracy of the technique in determining the invasion of serosa were 88%, 93%, and 91% for air-CT and 83%, 95%, and 91% for hydro-CT. There were no significant differences between hydro-MDCT and air-MDCT in sensitivity (P = 0.73), specificity (P = 0.71) and accuracy (P = 0.98). Conclusion: Air-MDCT is a very valuable tool in T-staging of gastric cancer as well as hydro-MDCT.

  18. T-staging of gastric cancer of air-filling multidetector-row CT: Comparison with hydro-multidetector-row CT

    Energy Technology Data Exchange (ETDEWEB)

    Kumano, Seishi, E-mail: kumano@radiol.med.kindai.ac.jp [Department of Radiology, Kinki University School of Medicine, Osakasayama, Osaka 589-8511 (Japan); Okada, Masahiro; Shimono, Taro; Kuwabara, Masatomo; Yagyu, Yukinobu; Imaoka, Izumi; Ashikaga, Ryuichiro; Ishii, Kazunari; Murakami, Takamichi [Department of Radiology, Kinki University School of Medicine, Osakasayama, Osaka 589-8511 (Japan)

    2012-11-15

    Purpose: The purpose of this study was to evaluate the accuracy of T-staging of gastric cancer by air-filling multidetector-row CT (air-MDCT) compared with water-filling MDCT (hydro-MDCT). Materials and methods: One hundred fifteen patients with histologically diagnosed gastric cancer were included in this study. Fifty-eight patients underwent air-MDCT, and the remaining 57 had hydro-MDCT using a 64-channel scanner. Based on the volumetric data of contrast-enhanced MDCT obtained about 75 s after intravenously injecting 525 mg iodine per kilogram patients weight (525 mgI/kg) nonionic contrast material at the rate of 2 ml/s, oblique coronal and oblique sagittal multi-planar reformatted images perpendicular to the stomach wall, including the tumor, were reconstructed on a workstation. Mural invasion of gastric cancer into the gastric wall, as visualized by CT, was classified according to the TNM classification, and the results of T-staging by MDCT were compared with those by pathologic analysis after surgery. Results: Correct assessment of T-staging by air-CT was achieved in 48 of 58 patients (83%), and that by hydro-MDCT was 49 of 57 patients (86%). The sensitivity, specificity, and accuracy of the technique in determining the invasion of serosa were 88%, 93%, and 91% for air-CT and 83%, 95%, and 91% for hydro-CT. There were no significant differences between hydro-MDCT and air-MDCT in sensitivity (P = 0.73), specificity (P = 0.71) and accuracy (P = 0.98). Conclusion: Air-MDCT is a very valuable tool in T-staging of gastric cancer as well as hydro-MDCT.

  19. A portable cadmium telluride multidetector probe for cardiac function monitoring

    CERN Document Server

    Arntz, Y; Dumitresco, B; Eclancher, B; Prat, V

    1999-01-01

    A new nuclear stethoscope based on a matrix of small CdTe semiconductor detectors has been developed for studying the cardiac performance by gamma ventriculography at the equilibrium, in rest and stress conditions, in the early and recovery phases of the coronary disease and to follow the long-term therapy. The light-weight probe consists of an array of 64 detectors 5x5x2 mm grouped in 16 independent units in a lead shielded aluminum box including 16 preamplifiers. The probe is connected to an electronic box containing DC power supply, 16 channel amplifiers, discriminators and counters, two analog-triggering ECG channels, and interface to a PC. The left ventricle activity is, preferentially, detected by using a low-resolution matching convergent collimator. A physical evaluation of the probe has been performed, both with static tests and dynamically with a hydraulic home-built model of beating heart ventricle paced by a rhythm simulator. The sum of the 16 detectors activity provided a radiocardiogram (RCG) wh...

  20. Multidetector CT and MRI findings in periportal space pathologies

    Energy Technology Data Exchange (ETDEWEB)

    Karcaaltincaba, Musturay [Department of Radiology, Hacettepe University School of Medicine, Ankara 06100 (Turkey)]. E-mail: musturayk@yahoo.com; Haliloglu, Mithat [Department of Radiology, Hacettepe University School of Medicine, Ankara 06100 (Turkey); Akpinar, Erhan [Department of Radiology, Hacettepe University School of Medicine, Ankara 06100 (Turkey); Akata, Deniz [Department of Radiology, Hacettepe University School of Medicine, Ankara 06100 (Turkey); Ozmen, Mustafa [Department of Radiology, Hacettepe University School of Medicine, Ankara 06100 (Turkey); Ariyurek, Macit [Department of Radiology, Hacettepe University School of Medicine, Ankara 06100 (Turkey); Akhan, Okan [Department of Radiology, Hacettepe University School of Medicine, Ankara 06100 (Turkey)

    2007-01-15

    Periportal region is an anatomic space around portal vein comprising hepatic artery, bile duct, nerves, lymphatics and a potential space. Periportal pathologies may involve any of these structures diffusely or focally with characteristic radiologic findings. Radiologic findings can be helpful in differential diagnosis of pathologies of periportal structures including periportal cavernomatous transformation, hepatic artery aneurysm, biliary diseases, neurofibromatosis, lymphoma, langerhans' cell histiocytosis, periportal fatty infiltration and other causes of periportal halo in adult and pediatric patients. Lobar/segmental intrahepatic involvement can be seen in neurofibromatosis, cavernomatous transformation, fatty infiltration and periportal edema. In this review, we discuss CT and MRI findings of periportal pathologies which can be in the form of diffuse or segmental/lobar involvement.

  1. Virtual anthropology and forensic identification using multidetector CT.

    Science.gov (United States)

    Dedouit, F; Savall, F; Mokrane, F-Z; Rousseau, H; Crubézy, E; Rougé, D; Telmon, N

    2014-04-01

    Virtual anthropology is made possible by modern cross-sectional imaging. Multislice CT (MSCT) can be used for comparative bone and dental identification, reconstructive identification and lesion identification. Comparative identification, the comparison of ante- and post-mortem imaging data, can be performed on both teeth and bones. Reconstructive identification, a considerable challenge for the radiologist, identifies the deceased by determining sex, geographical origin, stature and age at death. Lesion identification combines virtual autopsy and virtual anthropology. MSCT can be useful in palaeopathology, seeking arthropathy, infection, oral pathology, trauma, tumours, haematological disorders, stress indicators or occupational stress in bones and teeth. We examine some of the possibilities offered by this new radiological subspeciality that adds a new dimension to the work of the forensic radiologist. A multidisciplinary approach is crucial and involves communication and data exchange between radiologists, forensic pathologists, anthropologists and radiographers.

  2. Multidetector CT and MRI findings in periportal space pathologies

    International Nuclear Information System (INIS)

    Periportal region is an anatomic space around portal vein comprising hepatic artery, bile duct, nerves, lymphatics and a potential space. Periportal pathologies may involve any of these structures diffusely or focally with characteristic radiologic findings. Radiologic findings can be helpful in differential diagnosis of pathologies of periportal structures including periportal cavernomatous transformation, hepatic artery aneurysm, biliary diseases, neurofibromatosis, lymphoma, langerhans' cell histiocytosis, periportal fatty infiltration and other causes of periportal halo in adult and pediatric patients. Lobar/segmental intrahepatic involvement can be seen in neurofibromatosis, cavernomatous transformation, fatty infiltration and periportal edema. In this review, we discuss CT and MRI findings of periportal pathologies which can be in the form of diffuse or segmental/lobar involvement

  3. ROLE OF MULTIDETECTOR CT UROGRAPHY IN EVALUATING PATIENTS WITH HAEMATURIA

    Directory of Open Access Journals (Sweden)

    Varsha Rathi

    2016-07-01

    Full Text Available Haematuria is one of the commonest manifestation of urinary tract pathologies and requires thorough diagnostic workup. MDCT urography with its faster speed and multiplanar capabilities has become the investigation of choice in such cases. OBJECTIVES Our study was done with the aims of assessing the role of CT Urography in detecting the entire spectrum of urinary tract diseases causing haematuria and also to establish whether this single investigation suffices in directing the right management strategy in all these patients. MATERIALS AND METHODS This prospective study of 105 patients presenting with haematuria was done at a tertiary care government hospital at Nagpur over a period of two years. Two phase acquisition protocol (Split Bolus technique with saline distension was done in the majority of cases. Separate cortico-medullary phase images were acquired in cases of renal neoplasms for their better characterization. Images were viewed in axial as well as with 3D reformatted coronal planes. RESULTS Split bolus MDCT Urography with saline distension provided at least 50% opacification of urinary tract in about 94.8%. Major causes of haematuria in our study were urolithiasis (25.7%, Urothelial tract and bladder neoplasms (23.8% followed by renal neoplasms (16.2%. Developmental anomalies, infections and trauma were some other aetiologies. The overall sensitivity for upper urinary tract evaluation was 100%, while that for lower urinary tract was 88.4%. The overall positive predictive value was 97.4% in diagnosing haematuria by MDCT Urography. CONCLUSIONS CT Urography is highly accurate in evaluation of haematuria and definitely has potential to be one stop shop in evaluation of patients with haematuria. With the use of properly tailored protocols, the issue of radiation exposure can be addressed.

  4. Importance of multidetector CT imaging in multiple trauma; Stellenwert der Multidetektor-CT bei Polytrauma

    Energy Technology Data Exchange (ETDEWEB)

    Linsenmaier, U. [HELIOS Kliniken Muenchen West, HELIOS Klinik Muenchen Perlach, Institut fuer Diagnostische und Interventionelle Radiologie, Muenchen (Germany); Geyer, L.L.; Reiser, M.; Wirth, S. [Klinikum der Ludwig-Maximilians-Universitaet, Institut fuer Klinische Radiologie, Muenchen (Germany); Koerner, M. [Radiologie Muehleninsel, Landshut (Germany)

    2014-09-15

    Diagnostic imaging of complex multiple trauma remains a challenge for any department providing modern emergency radiology (ER) service. An early and comprehensive approach for ER imaging is crucial for a priority-oriented and timely therapy concept with the aim of identifying potentially life-threatening injuries early and initiating appropriate treatment. The basic diagnostic approach still consists of focused ultrasound using focused assessment with sonography for trauma (FAST) and conventional radiography (CR), usually limited to a single supine chest x-ray for triaging patients undergoing immediate operations. Multidetector computed tomography (MDCT) has become established as early whole body CT (WBCT) as the undisputable diagnostic method. The detection rate of injuries by WBCT is outstanding and it improves the probability of survival by 20-25 % compared with all other previous methods. At the same time, the spatial and temporal resolution of MDCT was improved resulting in considerably shortened examination times but WBCT is still associated with a significant radiation exposure, even in the acute single use setting. Using modern scanner and dose reduction technology, including iterative reconstruction, a dose reduction of up to 40 % could be achieved. The substantial number of images in WBCT is another challenge; images must be processed priority-oriented, read and transferred to the picture archiving and communications system (PACS). For rapid diagnosis, volume image reading (VIR) offers additional options to keep the diagnostic process on time. Modern WBCT after multiple trauma is performed early, comprehensively and personalized so that WBCT improves the probability of survival by 20-25 %. (orig.) [German] Die Diagnostik komplexer Mehrfachverletzungen ist eine Herausforderung fuer die moderne radiologische Notfalldiagnostik. Eine umfassend angelegte, fruehe und praezise radiologische Diagnostik ist entscheidend fuer eine prioritaetenorientierte und

  5. Scenes from the past: multidetector CT of Egyptian mummies of the Redpath Museum.

    Science.gov (United States)

    Wade, Andrew D; Garvin, Gregory J; Hurnanen, Jaana H; Williams, Licd Lana; Lawson, Barbara; Nelson, Andrew J; Tampieri, Donatella

    2012-01-01

    As a nondestructive method of historical and anthropologic inquiry, imaging has played an important role in mummy studies over the past several decades. Recent technologic advances have made multidetector computed tomography (CT) an especially useful means for deepening the present understanding of ancient cultures by examining preserved human remains. In April 2011, three ancient Egyptian human mummies from the Redpath Museum of McGill University were examined with 320-section multidetector CT as part of the IMPACT Radiological Mummy Database project headquartered at the University of Western Ontario. Whole-body scanning was performed with a section thickness of 0.5 mm and a peak voltage of 120 kVp, and the raw CT datasets were postprocessed by using smooth body and high-resolution bone convolution filters. Two of the mummies were scanned at different energy levels (80 and 135 keV). The high-resolution CT scans revealed the details of mummification and allowed observations about the socioeconomic and health status of the human subjects based on both the mummification technique used and the appearance of the remains, particularly the bones and teeth. The paleopathologic information obtained from the scans confirmed some findings in studies performed in the same mummies in the late 19th and 20th centuries. The CT scans also demonstrated a high degree of variability in Egyptian mortuary practice, variability that is not generally recognized in the literature. Unusual features that were observed included a relatively uncommon retained heart in mummy RM2718, retained lungs in a mummy from which the heart had been extracted (RM2720), and a cartonnage plaque placed over the left abdomen of a mummy that had been eviscerated transperineally (RM2717). PMID:22787004

  6. Scenes from the past: multidetector CT of Egyptian mummies of the Redpath Museum.

    Science.gov (United States)

    Wade, Andrew D; Garvin, Gregory J; Hurnanen, Jaana H; Williams, Licd Lana; Lawson, Barbara; Nelson, Andrew J; Tampieri, Donatella

    2012-01-01

    As a nondestructive method of historical and anthropologic inquiry, imaging has played an important role in mummy studies over the past several decades. Recent technologic advances have made multidetector computed tomography (CT) an especially useful means for deepening the present understanding of ancient cultures by examining preserved human remains. In April 2011, three ancient Egyptian human mummies from the Redpath Museum of McGill University were examined with 320-section multidetector CT as part of the IMPACT Radiological Mummy Database project headquartered at the University of Western Ontario. Whole-body scanning was performed with a section thickness of 0.5 mm and a peak voltage of 120 kVp, and the raw CT datasets were postprocessed by using smooth body and high-resolution bone convolution filters. Two of the mummies were scanned at different energy levels (80 and 135 keV). The high-resolution CT scans revealed the details of mummification and allowed observations about the socioeconomic and health status of the human subjects based on both the mummification technique used and the appearance of the remains, particularly the bones and teeth. The paleopathologic information obtained from the scans confirmed some findings in studies performed in the same mummies in the late 19th and 20th centuries. The CT scans also demonstrated a high degree of variability in Egyptian mortuary practice, variability that is not generally recognized in the literature. Unusual features that were observed included a relatively uncommon retained heart in mummy RM2718, retained lungs in a mummy from which the heart had been extracted (RM2720), and a cartonnage plaque placed over the left abdomen of a mummy that had been eviscerated transperineally (RM2717).

  7. Quantitative assessment of bone defect healing by multidetector CT in a pig model

    International Nuclear Information System (INIS)

    To evaluate multidetector CT volumetry in the assessment of bone defect healing in comparison to histopathological findings in an animal model. In 16 mini-pigs, a circumscribed tibial bone defect was created. Multidetector CT (MDCT) of the tibia was performed on a 64-row scanner 42 days after the operation. The extent of bone healing was estimated quantitatively by MDCT volumetry using a commercially available software programme (syngo Volume, Siemens, Germany).The volume of the entire defect (including all pixels from -100 to 3,000 HU), the nonconsolidated areas (-100 to 500 HU), and areas of osseous consolidation (500 to 3,000 HU) were assessed and the extent of consolidation was calculated. Histomorphometry served as the reference standard. The extent of osseous consolidation in MDCT volumetry ranged from 19 to 92% (mean 65.4 ± 18.5%). There was a significant correlation between histologically visible newly formed bone and the extent of osseous consolidation on MDCT volumetry (r = 0.82, P < 0.0001). A significant negative correlation was detected between osseous consolidation on MDCT and histological areas of persisting defect (r = -0.9, P < 0.0001). MDCT volumetry is a promising tool for noninvasive monitoring of bone healing, showing excellent correlation with histomorphometry. (orig.)

  8. Quantitative assessment of bone defect healing by multidetector CT in a pig model

    Energy Technology Data Exchange (ETDEWEB)

    Riegger, Carolin; Kroepil, Patric; Lanzman, Rotem S.; Miese, Falk R.; Antoch, Gerald; Scherer, Axel [University Duesseldorf, Medical Faculty, Department of Diagnostic and Interventional Radiology, Duesseldorf (Germany); Jungbluth, Pascal; Hakimi, Mohssen; Wild, Michael [University Duesseldorf, Medical Faculty, Department of Traumatology and Hand Surgery, Duesseldorf (Germany); Hakimi, Ahmad R. [Universtity Duesseldorf, Medical Faculty, Department of Oral Surgery, Duesseldorf (Germany)

    2012-05-15

    To evaluate multidetector CT volumetry in the assessment of bone defect healing in comparison to histopathological findings in an animal model. In 16 mini-pigs, a circumscribed tibial bone defect was created. Multidetector CT (MDCT) of the tibia was performed on a 64-row scanner 42 days after the operation. The extent of bone healing was estimated quantitatively by MDCT volumetry using a commercially available software programme (syngo Volume, Siemens, Germany).The volume of the entire defect (including all pixels from -100 to 3,000 HU), the nonconsolidated areas (-100 to 500 HU), and areas of osseous consolidation (500 to 3,000 HU) were assessed and the extent of consolidation was calculated. Histomorphometry served as the reference standard. The extent of osseous consolidation in MDCT volumetry ranged from 19 to 92% (mean 65.4 {+-} 18.5%). There was a significant correlation between histologically visible newly formed bone and the extent of osseous consolidation on MDCT volumetry (r = 0.82, P < 0.0001). A significant negative correlation was detected between osseous consolidation on MDCT and histological areas of persisting defect (r = -0.9, P < 0.0001). MDCT volumetry is a promising tool for noninvasive monitoring of bone healing, showing excellent correlation with histomorphometry. (orig.)

  9. Multidetector-row helical CT: analysis of time management and workflow

    International Nuclear Information System (INIS)

    The purpose of this study was to evaluate time management and workflow for multidetector-row helical CT (MDCT). Time for patient and data handling of at total of 580 patients were evaluated at two different time periods (December 1999, August 2000), each for the following baseline measurements: (a) change of clothes/instruction; (b) patient placement on the CT table/i.v. catheter; (c) CT planning and programming; (d) CT data acquisition; (e) CT data reconstruction; (f) CT data storage/printing. All imaging was performed on a Somatom Volume Zoom (Siemens, Erlangen, Germany). Time measurements summarized for different CT protocols revealed the following: (a) 5:01 min (±2.06 min); (b) 4:36 min (±2.43 min); (c) 4:11 min (±2.55 min); (d) 0:43 min (±0.15 min); (e) 6:59 min (±2.39 min); (f) 09:51 min (±3.51 min). Planning and programming was most time-consuming for CT angiography, whereas chest and abdominal CT needed only 3:26 and 3:30 min, respectively. Reconstruction time was highest for HRCT (9:22 min) and CTA (9:03 min). Data storage/printing was most time-consuming for HRCT (13:02 min), followed by combined neck-chest-abdomen examinations (12:19 min). Comparing the two time periods, during which a software update was performed, a mean time reduction of 4:31 min per patient (15%, p<0.001) was achieved. Whereas CT data acquisition time is no longer a problem with MDCT, patient management, data reconstruction, and data storage are the most time-consuming parts. Well-trained technicians, state-of-the-art workstations, and fast networking are the most important factors to improve workflow. (orig.)

  10. Congenital heart diseases: post-operative appearance on multi-detector CT - a pictorial essay

    Energy Technology Data Exchange (ETDEWEB)

    Tomasian, Anderanik; Malik, Sachin; Shamsa, Kamran; Krishnam, Mayil S. [UCLA Medical Center, Department of Radiological Science, Los Angeles, CA (United States)

    2009-12-15

    Echocardiography is considered as an initial imaging modality of choice in patients with congenital heart disease (CHD), and magnetic resonance (MR) imaging is preferred for detailed functional information. Multi-detector computed tomography (CT) plays an important role in clinical practice in assessing post-operative morphological and functional information of patients with complex CHD when echocardiography and MR imaging are not contributory. Radiologists should understand and become familiar with the complex morphology and physiology of CHD, as well as with various palliative and corrective surgical procedures performed in these patients, to obtain CT angiograms with diagnostic quality and promptly recognise imaging features of normal post-operative anatomy and complications of these complex surgeries. (orig.)

  11. Value of multidetector spiral CT in diagnosis of acute thoracolumbar spinal fracture and fracture-dislocation

    Institute of Scientific and Technical Information of China (English)

    龚静山; 徐坚民

    2004-01-01

    Objective:To investigate the diagnostic value of multidetector spiral CT (MSCT) in acute thoracolumbar spinal fracture and fracture-dislocation.Methods: CT imaging files of 152 consecutive traumatic patients with thoracolumbar fractures were retrospectively reviewed. MSCT scannings were performed with a collimation of 3-5 mm and a pitch of 5.5. The postprocessing included sagittal and coronal multiplannar reconstruction, and 3-D reconstruction.Result: There were 88 cases of compression fracture, 54 cases of burst fracture and 10 cases of fracasdislocation. Transverse images of MSCT could visualize all fractures directly and determine whether spinal canal was intact. Postprocessing image was helpful in depicting the displacement of fragment and orientation of dislocation.Conclusions: MSCT plays an important role in diagnosis and management of acute thoracolumbar spinal fracture and fracture-dislocation.

  12. Multidetector CT in emergency radiology: acute and generalized non-traumatic abdominal pain.

    Science.gov (United States)

    Paolantonio, Pasquale; Rengo, Marco; Ferrari, Riccardo; Laghi, Andrea

    2016-01-01

    Multidetector CT (MDCT) is an imaging technique that provides otherwise unobtainable information in the diagnostic work-up of patients presenting with acute abdominal pain. A correct working diagnosis depends essentially on understanding the individual patient's clinical data and laboratory findings. In haemodynamically stable patients with acute severe and generalized abdominal pain, MDCT is now the preferred imaging test and gives invaluable diagnostic information, also in unstable patients after stabilization. In this descriptive review, we focus our attention on acute, severe and generalized or undifferentiated non-traumatic abdominal pain. The main differential diagnoses are acute pancreatitis, gastrointestinal perforation, ruptured abdominal aneurysm and acute mesenteric ischaemia. We will provide radiologist readers with a technical guide to optimize MDCT imaging protocols and list the major CT signs essential to reach a correct diagnosis and guide the best treatment. PMID:26689097

  13. Congenital heart diseases: post-operative appearance on multi-detector CT - a pictorial essay

    International Nuclear Information System (INIS)

    Echocardiography is considered as an initial imaging modality of choice in patients with congenital heart disease (CHD), and magnetic resonance (MR) imaging is preferred for detailed functional information. Multi-detector computed tomography (CT) plays an important role in clinical practice in assessing post-operative morphological and functional information of patients with complex CHD when echocardiography and MR imaging are not contributory. Radiologists should understand and become familiar with the complex morphology and physiology of CHD, as well as with various palliative and corrective surgical procedures performed in these patients, to obtain CT angiograms with diagnostic quality and promptly recognise imaging features of normal post-operative anatomy and complications of these complex surgeries. (orig.)

  14. [Multidetector row CT in assessment of coronary artery calcification on hemodialisis].

    Science.gov (United States)

    Caro, P; Delgado, R; Dapena, F; Núñez, A

    2007-01-01

    Vascular calcification is a strong predictor of cardiovascular and all-cause mortality. Coronary artery calcification is more frequent, more extensive and progresses more rapidly in CKD than in general population. They are also considered a marker of coronary heart disease, with high prevalence and functional significance. It suggests that detection and surveillance may be worthwhile in general clinical practice. New non-invasive image techniques, like Multi-detector row CT, a type of spiral scanner, assess density and volume of calcification at multiple sites and allow quantitative scoring of vascular calcification using calcium scores analogous to those from electron-beam CT. We have assessed and quantified coronary artery calcification with 16 multidetector row CT in 44 patients on hemodialysis and their relationship with several cardiovascular risk factors. Coronary artery calcification prevalence was of 84 % with mean calcium score of 1580 +/- 2010 ( r 0-9844) with calcium score > 400 in 66% of patients. It was usually multiple, affecting more than two vessels in more than 50%. In all but one patient, left anterior descending artery was involved with higher calcium score level at right coronary artery. Advanced age, male, diabetes, smoking, more morbidity, cerebrovascular disease previous, and calcium-binders phosphate and analogous vitamin D treatment would seem to be associated with coronary artery calcification. Coronary artery calcification is very frequent and extensive, usually multiple and associated to modifiable risk factors in hemodialysis patients. Multi-detector-row CT seems an effective, suitable, readily applicable method to assess and quantify coronary artery calcification. PMID:18336102

  15. Detection of hypervascular hepatocellular carcinoma: Comparison of multi-detector CT with digital subtraction angiography and Lipiodol CT

    Institute of Scientific and Technical Information of China (English)

    Xiao-Hua Zheng; Yong-Song Guan; Xiang-Ping Zhou; Juan Huang; Long Sun; Xiao Li; Yuan Liu

    2005-01-01

    AIM: The purpose of this study was to compare the diagnostic accuracy of biphasic multi-detector row helical computed tomography (MDCT), digital subtraction angiography (DSA)and Lipiodol computed tomography (CT) in detection of hypervascular hepatocellular carcinoma (HCC).METHODS: Twenty-eight patients with nodular HCC underwent biphasic MDCT examination: hepatic arterial phase (HAP) 25 s and portal venous phase (PVP) 70 s after injection of the contrast medium (1.5 mL/kg). They also underwent hepatic angiography and intra-arterial infusion of iodized oil. Lipiodol CT was performed 3-4 wk after infusion. MDCT images were compared with DSA and Lipiodol CT images for detection of hepatic nodules.RESULTS: The three imaging techniques had the same sensitivity in detecting nodules >20 mm in diameter. There was no significant difference in the sensitivity among HAP-MDCT, Lipiodol CT and DSA for nodules of 10-20 mm in diameter. For the nodules <10 mm in diameter, HAP-MDCT identified 47, Lipiodol CT detected 27 (X2= 11.3, P= 0.005<0.01, HAP-MDCT vs Lipiodol CT) and DSA detected 16(X2= 9.09, P= 0.005<0.01 vs Lipiodol CT and X2= 29.03,P = 0.005<0.01 vs HAP-MDCT). However, six nodules <10 mm in diameter were detected only by Lipiodol CT.CONCLUSION: MDCT and Lipiodol CT are two complementary modalities. At present, MDCT does not obviate the need for DSA and subsequent Lipiodol CT as a preoperative examination for HCC.

  16. Influence of z overscanning on normalized effective doses calculated for pediatric patients undergoing multidetector CT examinations

    International Nuclear Information System (INIS)

    The purpose of this study was to evaluate the effect of z overscanning on normalized effective dose for pediatric patients undergoing multidetector-computed tomography (CT) examinations. Five commercially available mathematical anthropomorphic phantoms representing newborn, 1-, 5-, 10-, and 15-year-old patients and the Monte Carlo N-Particle (MCNP, version 4C2) radiation transport code were employed in the current study to simulate pediatric CT exposures. For all phantoms, axial and helical examinations at 120 kV tube voltage were simulated. Scans performed at 80 kV were also simulated. Sex-specific normalized effective doses were estimated for four standard CT examinations i.e., head-neck, chest, abdomen-pelvis, and trunk, for all pediatric phantoms. Data for both axial and helical mode acquisition were obtained. In the helical mode, z overscanning was taken into account. The validity of the Monte Carlo results was verified by comparison with dose data obtained using thermoluminescence dosimetry and a physical pediatric anthropomorphic phantom simulating a 10-year-old child. In all cases normalized effective dose values were found to increase with increasing z overscanning. The percentage differences in normalized data between axial and helical scans may reach 43%, 70%, 36%, and 26% for head-neck, chest, abdomen-pelvis, and trunk studies, respectively. Normalized data for female pediatric patients was in general higher compared to male patients for all ages, examined regions, and z overscanning values. For both male and female children, the normalized effective dose values were reduced as the age was increased. For the same typical exposure conditions, dose values decreased when lower tube voltage was used; for a 1-year-old child, for example, the effective dose was 3.8 times lower when 80 kV instead of 120 kV was used. Normalized data for the estimation of effective dose to pediatric patients undergoing standard axial and helical CT examinations on an

  17. A novel iterative reconstruction algorithm allows reduced dose multidetector-row CT imaging of mechanical prosthetic heart valves

    OpenAIRE

    Habets, Jesse; Symersky, Petr; de Mol, Bas A. J. M.; Willem P Th M Mali; Leiner, Tim; Budde, Ricardo P.J.

    2011-01-01

    Multidetector-row CT is promising for prosthetic heart valve (PHV) assessment but retrospectively ECG-gated scanning has a considerable radiation dose. Recently introduced iterative reconstruction (IR) algorithms may enable radiation dose reduction with retained image quality. Furthermore, PHV image quality on the CT scan mainly depends on extent of PHV artifacts. IR may decrease streak artifacts. We compared image noise and artifact volumes in scans of mechanical PHVs reconstructed with conv...

  18. Volumetric Measurements of Lung Nodules with Multi-Detector Row CT: Effect of Changes in Lung Volume

    OpenAIRE

    Goo, Jin Mo; Kim, Kwang Gi; Gierada, David S.; Castro, Mario; Bae, Kyongtae T.

    2006-01-01

    Objective To evaluate how changes in lung volume affect volumetric measurements of lung nodules using a multi-detector row CT. Materials and Methods Ten subjects with asthma or chronic bronchitis who had one or more lung nodules were included. For each subject, two sets of CT images were obtained at inspiration and at expiration. A total of 33 nodules (23 nodules ≥ 3 mm) were identified and their volume measured using a semiautomatic volume measurement program. Differences between nodule volu...

  19. 64 multidetector CT findings of influenza A (H1N1) virus in patients with hematologic malignancies

    International Nuclear Information System (INIS)

    Background. The pandemic of swine-origin H1N1 influenza that began in early 2009 has provided evidence that radiology can assist in the early diagnosis of severe cases. Immunocompromised patients are at increased risk for morbidity and mortality. MDCT is superior to radiography in showing the distribution of the disease. Purpose. To review the 64 multidetector CT thoracic findings of novel swine-origin influenza A (H1N1) virus in patients with hematologic malignancies. Material and Methods. This study included 12 patients (3 women, 9 men; mean age, 32.2 years). All patients proved to be infected with influenza A (H1N1) virus. The hematologic malignancies were acute myeloid leukemia (n = 8), chronic lymphocytic leukemia (n = 2), multiple myeloma (n = 1), and myelodysplastic syndrome (n = 1). All the patients underwent CT scanning using a 64 multidetector CT scanner. Chest CT scans were reviewed for ground-glass opacities (GGOs), consolidation, airway thickening/dilatation, nodules, mediastinal lymphadenopathy, and pleural effusion. Results. More than one CT finding was detected in every patient. Pulmonary affection was bilateral, more on the left side. The affections were mainly peribronchial. Airway wall thickening and dilatation were detected in all 12 patients, GGO in 9/12 patients, nodules in 6/12 patients, consolidation in 6/12 patients, hilar lymphadenopathy in 3/12 patients, and pleural effusion in 2/12 patients. Conclusion. Acute myeloid leukemia is the most common hematologic malignancy affected by influenza A (H1N1) virus. The left lung is affected more than the right one. The most common multidetector CT findings are unilateral or bilateral airway thickening and dilatation. Multidetector CT can be used for early and accurate assessment of pulmonary affection with influenza A H1N1 virus infection

  20. 64 multidetector CT findings of influenza A (H1N1) virus in patients with hematologic malignancies

    Energy Technology Data Exchange (ETDEWEB)

    El-Badrawy, Adel [Dept. of Radiology, Mansoura Faculty of Medicine, Mansoura (Egypt)], E-mail: adelelbadrawy@hotmail.com; Zeidan, Amany [Dept. of Thoracic Medicine, Mansoura Faculty of Medicine, Mansoura (Egypt); Ebrahim, Mohamed A. [Dept. of Medical Oncology, Mansoura Faculty of Medicine, Mansoura (Egypt)

    2012-07-15

    Background. The pandemic of swine-origin H1N1 influenza that began in early 2009 has provided evidence that radiology can assist in the early diagnosis of severe cases. Immunocompromised patients are at increased risk for morbidity and mortality. MDCT is superior to radiography in showing the distribution of the disease. Purpose. To review the 64 multidetector CT thoracic findings of novel swine-origin influenza A (H1N1) virus in patients with hematologic malignancies. Material and Methods. This study included 12 patients (3 women, 9 men; mean age, 32.2 years). All patients proved to be infected with influenza A (H1N1) virus. The hematologic malignancies were acute myeloid leukemia (n = 8), chronic lymphocytic leukemia (n = 2), multiple myeloma (n = 1), and myelodysplastic syndrome (n = 1). All the patients underwent CT scanning using a 64 multidetector CT scanner. Chest CT scans were reviewed for ground-glass opacities (GGOs), consolidation, airway thickening/dilatation, nodules, mediastinal lymphadenopathy, and pleural effusion. Results. More than one CT finding was detected in every patient. Pulmonary affection was bilateral, more on the left side. The affections were mainly peribronchial. Airway wall thickening and dilatation were detected in all 12 patients, GGO in 9/12 patients, nodules in 6/12 patients, consolidation in 6/12 patients, hilar lymphadenopathy in 3/12 patients, and pleural effusion in 2/12 patients. Conclusion. Acute myeloid leukemia is the most common hematologic malignancy affected by influenza A (H1N1) virus. The left lung is affected more than the right one. The most common multidetector CT findings are unilateral or bilateral airway thickening and dilatation. Multidetector CT can be used for early and accurate assessment of pulmonary affection with influenza A H1N1 virus infection.

  1. Cardiac CT for the assessment of chest pain: Imaging techniques and clinical results

    Energy Technology Data Exchange (ETDEWEB)

    Becker, Hans-Christoph, E-mail: christoph.becker@med.uni-muenchen.de [Ludwig-Maximilians-University, Grosshadern Clinic, Department of Clinical Radiology, Marchioninistr. 15, 81377 Munich (Germany); Johnson, Thorsten [Ludwig-Maximilians-University, Grosshadern Clinic, Department of Clinical Radiology, Marchioninistr. 15, 81377 Munich (Germany)

    2012-12-15

    Immediate and efficient risk stratification and management of patients with acute chest pain in the emergency department is challenging. Traditional management of these patients includes serial ECG, laboratory tests and further on radionuclide perfusion imaging or ECG treadmill testing. Due to the advances of multi-detector CT technology, dedicated coronary CT angiography provides the potential to rapidly and reliably diagnose or exclude acute coronary artery disease. Life-threatening causes of chest pain, such as aortic dissection and pulmonary embolism can simultaneously be assessed with a single scan, sometimes referred to as “triple rule out” scan. With appropriate patient selection, cardiac CT can accurately diagnose heart disease or other sources of chest pain, markedly decrease health care costs, and reliably predict clinical outcomes. This article reviews imaging techniques and clinical results for CT been used to evaluate patients with chest pain entering the emergency department.

  2. Xenon/CT blood flow mapping of the liver using multidetector-row computed tomography. Compensation of respiratory misregistration by volume data

    International Nuclear Information System (INIS)

    For improvement in the accuracy of xenon/CT blood flow mapping of the liver, this study was conducted to assess whether volume-data obtained by multidetector-row helical CT could compensate for the slice misregistration caused by inconstant breath depth. Using imaging phantoms scanned on both multidetector-row and single-detector CT, suitable parameters were decided. In the phantom studies, axial scan with multidetector-row CT showed significantly greater variance of CT value than that of single detector row CT (SDCT). On multidetector-row CT, variances of the CT values maintained in low (80 kV) tube voltage, which is advantageous for detecting subtle enhancement of the liver. Images reconstructed with 10-mm thickness showed smaller variance than those of 5-mm thickness on low-pitch helical scan. Remarkable helical artifacts were seen on the high-pitch helical scan. Following the phantom studies, 7 examinees were scanned using xenon/CT with a predetermined scan protocol (80 kV, collimation 5 mm, thickness 10 mm, low-pitch helical scan). In all cases, slice compensation was necessary and was successfully performed. The number of pixels which constituted blood flow map increased after the compensation. No patients showed any significant adverse effects. In conclusion, multidetector-row helical CT has the potential for providing accurate quantification of xenon/CT blood flow mapping of liver by compensating for respiratory misregistration. (author)

  3. Practical textbook of cardiac CT and MRI

    Energy Technology Data Exchange (ETDEWEB)

    Lim, Tae-Hwan (ed.) [ASAN Medical Center, Seoul (Korea, Republic of). Dept. of Radiology

    2015-04-01

    Guide to the interpretation of cardiac CT and MRI for the purposes of diagnosis, treatment planning, and follow-up. Emphasis on applications in a wide range of real clinical situations. Numerous informative illustrations. Summarizing sections permitting rapid retrieval of information. QR codes allowing access to references, additional figures, and motion pictures from the internet. This up-to-date textbook comprehensively reviews all aspects of cardiac CT and MRI and demonstrates the value of these techniques in clinical practice. A wide range of applications are considered, including imaging of atherosclerotic and non-atherosclerotic coronary artery disease, coronary revascularization, ischemic heart disease, non-ischemic cardiomyopathy, valvular heart disease, cardiac tumors, and pericardial disease. The numerous high-quality images illustrate how to interpret cardiac CT and MRI correctly for the purposes of diagnosis, treatment planning, and follow-up. Helpful summarizing sections in every chapter will facilitate rapid retrieval of information. This book will be of great value to radiologists and cardiologists seeking a reliable guide to the optimal use of cardiac CT and MRI in real clinical situations.

  4. Comparison of Multidetector CT Angiographic Findings with Operative Findings of Renal Vasculature in Living Renal Donors

    Directory of Open Access Journals (Sweden)

    Soodeh Sagheb

    2010-05-01

    Full Text Available Background/Objective: In kidney transplantation, decision about donation of the proper kidney is not the same between different surgeons. One of the most important factors for choosing the best kidney for transplantation is a simple vasculature anatomy and a kidney without abnormalities. In laparoscopic nephrectomy, the left kidney is preferred, because it has a longer renal vein and the renal artery is not behind the inferior vena cava (IVC. In other situations, in order to reduce the vascular morbidity of the surgery, nephrectomy is on the side which has a simpler vascular anatomy."nAssessment of renal vasculature of a live donor with noninvasive techniques is a necessity for live donors. For delineation of vascular anomalies of the kidney as well as urinary system abnormalities, Multi-Detector CT seems to be an excellent method for evaluation."nPatients and Methods: In this study, 59 live donors were assessed with multi-detector CT angiography. After injection of 80 ml contrast media, we acquired CT images with 0.6 mm slice thickness. Finally, processing and three dimensional reconstructions were performed and the accessory arteries, early branching of the main renal artery, the number of main renal vessels and the ureters were assessed. Findings were compared with the nephrectomy results."nResults: In multi slice CT angiography the prevalence of accessory renal artery was 3.4% with 98% accuracy, early branching of the main renal artery was 8.4% with 100% accuracy. Multiplicity of renal veins was seen in 8.4% of donors with 98% accuracy. Duplicated ureter was not seen in any of the donors."nDiscussion: The accuracy of CT angiography is 95% for depicting accessory renal artery and multiple renal artery and 100% for early branching. These results were comparable with the findings in conventional angiography and the studies showed that this method is more valuable in comparison with MR angiography and digital subtraction angiography. Also, it is

  5. Chronic thromboembolic pulmonary hypertension (CTEPH). Potential role of multidetector-row CT (MD-CT) and MR imaging in the diagnosis and differential diagnosis of the disease

    Energy Technology Data Exchange (ETDEWEB)

    Wirth, G.; Brueggemann, K.; Bostel, T.; Dueber, C.; Kreitner, K.F. [Universitaetsmedizin Mainz (Germany). Dept. of Radiology; Mayer, E. [Kerckhoff Hospital, Bad Nauheim (Germany). Dept. of Thoracic Surgery

    2014-08-15

    Chronic thromboembolic pulmonary hypertension (CTEPH) can be defined as pulmonary hypertension (resting mean pulmonary arterial pressure of 25 mm Hg or more determined at right heart catheterization) with persistent pulmonary perfusion defects. It is a rare, but underdiagnosed disease with estimated incidences ranging from 0.5% to 3.8% of patients after an acute pulmonary embolism (PE), and in up to 10% of those with a history of recurrent PE. CTEPH is the only form of pulmonary hypertension that can be surgically treated leading to normalization of pulmonary hemodynamics and exercise capacity in the vast majority of patients. The challenges for imaging in patients with suspected CTEPH are fourfold: the imaging modality should have a high diagnostic accuracy with regard to the presence of CTEPH and allow for differential diagnosis. It should enable detection of patients suitable for PEA with great certainty, and allow for quantification of PH by measuring pulmonary hemodynamics (mPAP and PVR), and finally, it can be used for therapy monitoring. This overview tries to elucidate the potential role of ECG-gated multidetector CT pulmonary angiography (MD-CTPA) and MR imaging, and summarizes the most important results that have been achieved so far. Generally speaking, ECG-gated MD-CTPA is superior to MR in the assessment of parenchymal and vascular pathologies of the lung, and allows for the assessment of cardiac structures. The implementation of iodine maps as a surrogate for lung perfusion enables functional assessment of lung perfusion by CT. MR imaging is the reference standard for the assessment of right heart function and lung perfusion, the latter delineating typical wedge-shaped perfusion defects in patients with CTEPH. New developments show that with MR techniques, an estimation of hemodynamic parameters like mean pulmonary arterial pressure and pulmonary vascular resistance will be possible. CT and MR imaging should be considered as complementary

  6. Chronic thromboembolic pulmonary hypertension (CTEPH). Potential role of multidetector-row CT (MD-CT) and MR imaging in the diagnosis and differential diagnosis of the disease

    International Nuclear Information System (INIS)

    Chronic thromboembolic pulmonary hypertension (CTEPH) can be defined as pulmonary hypertension (resting mean pulmonary arterial pressure of 25 mm Hg or more determined at right heart catheterization) with persistent pulmonary perfusion defects. It is a rare, but underdiagnosed disease with estimated incidences ranging from 0.5% to 3.8% of patients after an acute pulmonary embolism (PE), and in up to 10% of those with a history of recurrent PE. CTEPH is the only form of pulmonary hypertension that can be surgically treated leading to normalization of pulmonary hemodynamics and exercise capacity in the vast majority of patients. The challenges for imaging in patients with suspected CTEPH are fourfold: the imaging modality should have a high diagnostic accuracy with regard to the presence of CTEPH and allow for differential diagnosis. It should enable detection of patients suitable for PEA with great certainty, and allow for quantification of PH by measuring pulmonary hemodynamics (mPAP and PVR), and finally, it can be used for therapy monitoring. This overview tries to elucidate the potential role of ECG-gated multidetector CT pulmonary angiography (MD-CTPA) and MR imaging, and summarizes the most important results that have been achieved so far. Generally speaking, ECG-gated MD-CTPA is superior to MR in the assessment of parenchymal and vascular pathologies of the lung, and allows for the assessment of cardiac structures. The implementation of iodine maps as a surrogate for lung perfusion enables functional assessment of lung perfusion by CT. MR imaging is the reference standard for the assessment of right heart function and lung perfusion, the latter delineating typical wedge-shaped perfusion defects in patients with CTEPH. New developments show that with MR techniques, an estimation of hemodynamic parameters like mean pulmonary arterial pressure and pulmonary vascular resistance will be possible. CT and MR imaging should be considered as complementary

  7. Usefulness of multiplanar reformatted images of multi-detector row helical CT in assessment of biliary stent patency

    International Nuclear Information System (INIS)

    To evaluate the usefulness of multi-detector row helical CT (MDCT), multiplanar reformatted images for the noninvasive assessment of biliary stent patency, and for the planning for management in patients with a sele-expandable metallic stent due to malignant biliary obstruction. Among 90 consecutive patients, from August 1999 to July 2003, 26 cases in 23 patients with malignant biliary obstruction who underwent self-expandable metaIlic stent insertion in the biliary system and percutaneous transhepatic biliary drainage within 7 days after CT were enrolled in this study. On CT images, the complete and functional obstruction of the stent and the precise level of obstruction were evaluated. The presence of an enhancing intraluminal mass or wall thickening around stent was determined, and the causes of obstruction were evaluated. These findings were then compared with percutaneous transhepatic cholangiography. Multi-detector row helical CT correctly demonstrated the patency of a stent in 24 cases (92.3%). It was adequate in helping to depict the precise level of stent occlusion in 23 cases (88.5%). Multi-detector row helical CT also revealed the extent of tumor that represented as an enhancing intraluminal mass or wall thickening around the stent in 23 cases, and this was represented as complete obstruction on percutaneous transhepatic cholangiography. In the case of functional obstruction, MDCT predicted the possible cause of the obstruction. Multiplanar reformatted images of multi-detector row helical CT is a useful imaging modality for the noninvasive assessment of stent patency and the precise level of obstruction when stent obstruction is suspected in the patients with self-expandable metallic stent due to malignant biliary obstruction. It can also predict the possible cause of the obstruction and allows adequate planning for the medical management of such cases

  8. Integrated cardio-thoracic imaging with ECG-Gated 64-slice multidetector-row CT: initial findings in 133 patients

    Energy Technology Data Exchange (ETDEWEB)

    Salem, Randa; Remy-Jardin, Martine; Delhaye, Damien; Khalil, Chadi; Teisseire, Antoine; Remy, Jacques [Hospital Calmette, University Center of Lille, Department of Thoracic Imaging, LILLE cedex (France); Delannoy-Deken, Valerie; Duhamel, Alain [University of Lille, Place de Verdun, Department of Medical Statistics, LILLE cedex (France)

    2006-09-15

    The purpose of this study was to investigate the possibility of assessing the underlying respiratory disease as well as cardiac function during ECG-gated CT angiography of the chest with 64-slice multidetector-row CT (MDCT). One hundred thirty-three consecutive patients in sinus rhythm with known or suspected ventricular dysfunction underwent an ECG-gated CT angiographic examination of the chest without {beta}-blockers using the following parameters: (1) collimation: 32 x 0.6 mm with z-flying focal spot for the acquisition of 64 overlapping 0.6-mm slices (Sensation 64; Siemens); rotation time: 0.33 s; pitch: 0.3; 120 kV; 200 mAs; ECG-controlled dose modulation (ECG-pulsing) and (2) 120 ml of a 35% contrast agent. Data were reconstructed: (1) to evaluate the underlying respiratory disease (1-mm thick lung and mediastinal scans reconstructed at 55% of the R-R interval; i.e., ''morphologic scans'') and (2) to determine right (RVEF) and left (LVEF) ventricular ejection fractions (short-axis systolic and diastolic images; Argus software; i.e., ''functional scans''). The mean heart rate was 73 bpm (range: 42-120) and the mean scan time was 18.11{+-}2.67 s (range: 10-27). A total of 123 examinations (92%) had both lung and mediastinal images rated as diagnostic scans, whereas 10 examinations (8%) had non-diagnostic images altered by the presence of respiratory-motion artifacts (n=4) or cyclic artifacts related to the use of a pitch value of 0.3 in patients with a very low heart rate during data acquisition (n=6). Assessment of right and left ventricular function was achievable in 124 patients (93%, 95% CI: 88-97%). For these 124 examinations, the mean RVEF was 46.10% ({+-}9.5; range: 20-72) and the mean LVEF was 58.23% ({+-}10.88; range: 20-83). In the remaining nine patients, an imprecise segmentation of the right and left ventricular cavities was considered as a limiting factor for precise calculation of end-systolic and end

  9. Radiation dose from multidetector CT studies in children: results from the first Italian nationwide survey

    International Nuclear Information System (INIS)

    Multidetector CT (MDCT) scanners have contributed to the widespread use of CT in paediatric imaging. However, concerns are raised for the associated radiation exposure. Very few surveys on radiation exposure from MDCT studies in children are available. The aim of this study was to outline the status of radiation exposure in children from MDCT practice in Italy. In this retrospective multicentre study we asked Italian radiology units with an MDCT scanner with at least 16 slices to provide dosimetric and acquisition parameters of CT examinations in three age groups (1-5, 6-10, 11-15 years) for studies of head, chest and abdomen. The dosimetric results were reported in terms of third-quartile volumetric CT dose index (CTDIvol) (mGy), size-specific dose estimate (SSDE) (mGy), dose length product (DLP) (mGy cm), and total DLP for multiphase studies. These results were compared with paediatric European and adult Italian published data. A multivariate analysis assessed the association of CTDIvol with patient characteristics and scanning modalities. We collected data from 993 MDCT examinations performed at 25 centres. For age groups 1-5 years, 6-10 years and 11-15 years, the CTDIvol, DLP and total DLP values were statistically significantly below the values observed in our analogous national survey in adults, although the difference decreased with increasing age. CTDIvol variability among centres was statistically significant (variance = 0.07; 95% confidence interval = 0.03-0.16; P < 0.001). This study reviewed practice in Italian centres performing paediatric imaging with MDCT scanners. The variability of doses among centres suggests that the use of standardised CT protocols should be encouraged. (orig.)

  10. Radiation dose from multidetector CT studies in children: results from the first Italian nationwide survey

    Energy Technology Data Exchange (ETDEWEB)

    Granata, Claudio [IRCCS Istituto Giannina Gaslini, Department of Radiology, Genoa (Italy); Origgi, Daniela; Palorini, Federica [Istituto Europeo di Oncologia, Department of Medical Physics, Milan (Italy); Matranga, Domenica [University of Palermo, Department of Sciences for Health Promotion and Mother and Child Care ' ' G. D' Alessandro' ' , Palermo (Italy); Salerno, Sergio [University of Palermo, Department of Medical and Forensic Biopathology and Biotechnologies, Section of Radiology, Palermo (Italy)

    2015-05-01

    Multidetector CT (MDCT) scanners have contributed to the widespread use of CT in paediatric imaging. However, concerns are raised for the associated radiation exposure. Very few surveys on radiation exposure from MDCT studies in children are available. The aim of this study was to outline the status of radiation exposure in children from MDCT practice in Italy. In this retrospective multicentre study we asked Italian radiology units with an MDCT scanner with at least 16 slices to provide dosimetric and acquisition parameters of CT examinations in three age groups (1-5, 6-10, 11-15 years) for studies of head, chest and abdomen. The dosimetric results were reported in terms of third-quartile volumetric CT dose index (CTDI{sub vol}) (mGy), size-specific dose estimate (SSDE) (mGy), dose length product (DLP) (mGy cm), and total DLP for multiphase studies. These results were compared with paediatric European and adult Italian published data. A multivariate analysis assessed the association of CTDI{sub vol} with patient characteristics and scanning modalities. We collected data from 993 MDCT examinations performed at 25 centres. For age groups 1-5 years, 6-10 years and 11-15 years, the CTDI{sub vol}, DLP and total DLP values were statistically significantly below the values observed in our analogous national survey in adults, although the difference decreased with increasing age. CTDI{sub vol} variability among centres was statistically significant (variance = 0.07; 95% confidence interval = 0.03-0.16; P < 0.001). This study reviewed practice in Italian centres performing paediatric imaging with MDCT scanners. The variability of doses among centres suggests that the use of standardised CT protocols should be encouraged. (orig.)

  11. Cardiac fusion and complex congenital cardiac defects in thoracopagus twins: diagnostic value of cardiac CT

    Energy Technology Data Exchange (ETDEWEB)

    Goo, Hyun Woo [University of Ulsan College of Medicine, Asan Medical Center, Department of Radiology and Research Institute of Radiology, Seoul (Korea, Republic of); Park, Jeong-Jun [University of Ulsan College of Medicine, Asan Medical Center, Department of Pediatric Cardiac Surgery, Seoul (Korea, Republic of); Kim, Ellen Ai-Rhan [University of Ulsan College of Medicine, Asan Medical Center, Division of Neonatology, Department of Pediatrics, Seoul (Korea, Republic of); Won, Hye-Sung [University of Ulsan College of Medicine, Asan Medical Center, Department of Obstetrics and Gynecology, Seoul (Korea, Republic of)

    2014-09-15

    Most thoracopagus twins present with cardiac fusion and associated congenital cardiac defects, and assessment of this anatomy is of critical importance in determining patient care and outcome. Cardiac CT with electrocardiographic triggering provides an accurate and quick morphological assessment of both intracardiac and extracardiac structures in newborns, making it the best imaging modality to assess thoracopagus twins during the neonatal period. In this case report, we highlight the diagnostic value of cardiac CT in thoracopagus twins with an interatrial channel and complex congenital cardiac defects. (orig.)

  12. Unenhanced multidetector CT (CT KUB) in the initial imaging of suspected acute renal colic: evaluating a new service

    Energy Technology Data Exchange (ETDEWEB)

    Chowdhury, F.U. [Departments of Clinical Radiology, Leeds Teaching Hospitals, Leeds (United Kingdom); Kotwal, S. [Urology, Leeds Teaching Hospitals, Leeds (United Kingdom); Raghunathan, G.; Wah, T.M. [Departments of Clinical Radiology, Leeds Teaching Hospitals, Leeds (United Kingdom); Joyce, A. [Urology, Leeds Teaching Hospitals, Leeds (United Kingdom); Irving, H.C. [Departments of Clinical Radiology, Leeds Teaching Hospitals, Leeds (United Kingdom)], E-mail: henry.irving@leedsth.nhs.uk

    2007-10-15

    Aim: To evaluate a new imaging pathway for the investigation of patients presenting with suspected acute renal colic. Materials and methods: A retrospective review of 500 consecutive cases of suspected acute renal colic was undertaken to evaluate the initial results of a new imaging pathway introduced at our institution, which completely replaced the intravenous urogram (IVU) with unenhanced multidetector CT (CT KUB). Results: The positive rate for urolithiasis was 44% (221/500), the negative rate 46% (229/500) and the rate of other significant findings was 12% (59/500). Female patients had a low positive rate compared with male patients (27.5 versus 57.5%; p < 0.001). Urological intervention was required in 28% (61/221) and these patients had a larger average stone size (6.6 versus 3.7 mm; p < 0.001) and the stone was located more proximally. Out-of-hours imaging was performed in 37% (186/500), and these patients had a higher positive rate (52 versus 40%; p < 0.001). Other findings included a wide range of acute non-urological conditions. Conclusion: The feasibility of replacing the acute IVU with CT KUB in the initial assessment of suspected acute renal colic was demonstrated in the present study. The technique enables rapid diagnosis of urolithiasis, stratification of patients likely to proceed to urological intervention, and prompt diagnosis of a variety of other acute pathological conditions.

  13. Evaluation of accuracy of 3D reconstruction images using multi-detector CT and cone-beam CT

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Mi Ja [Graduate School of Clinical Dentistry, Hallym University, Seoul (Korea, Republic of); Huh, Kyung Hoe; Yi, Won Jin; Heo, Min Suk; Lee, Sam Sun; Choi, Soon Chul [School of Dentistry, Seoul National University, Seoul (Korea, Republic of)

    2012-03-15

    This study was performed to determine the accuracy of linear measurements on three-dimensional (3D) images using multi-detector computed tomography (MDCT) and cone-beam computed tomography (CBCT). MDCT and CBCT were performed using 24 dry skulls. Twenty-one measurements were taken on the dry skulls using digital caliper. Both types of CT data were imported into OnDemand software and identification of landmarks on the 3D surface rendering images and calculation of linear measurements were performed. Reproducibility of the measurements was assessed using repeated measures ANOVA and ICC, and the measurements were statistically compared using a Student t-test. All assessments under the direct measurement and image-based measurements on the 3D CT surface rendering images using MDCT and CBCT showed no statistically difference under the ICC examination. The measurements showed no differences between the direct measurements of dry skull and the image-based measurements on the 3D CT surface rendering images (P>.05). Three-dimensional reconstructed surface rendering images using MDCT and CBCT would be appropriate for 3D measurements.

  14. New horizons in cardiac CT.

    Science.gov (United States)

    den Harder, A M; Willemink, M J; de Jong, P A; Schilham, A M R; Rajiah, P; Takx, R A P; Leiner, T

    2016-08-01

    Until recently, cardiovascular computed tomography angiography (CCTA) was associated with considerable radiation doses. The introduction of tube current modulation and automatic tube potential selection as well as high-pitch prospective ECG-triggering and iterative reconstruction offer the ability to decrease dose with approximately one order of magnitude, often to sub-millisievert dose levels. In parallel, advancements in computational technology have enabled the measurement of fractional flow reserve (FFR) from CCTA data (FFRCT). This technique shows potential to replace invasively measured FFR to select patients in need of coronary intervention. Furthermore, developments in scanner hardware have led to the introduction of dual-energy and photon-counting CT, which offer the possibility of material decomposition imaging. Dual-energy CT reduces beam hardening, which enables CCTA in patients with a high calcium burden and more robust myocardial CT perfusion imaging. Future-generation CT systems will be capable of counting individual X-ray photons. Photon-counting CT is promising and may result in a substantial further radiation dose reduction, vastly increased spatial resolution, and the introduction of a whole new class of contrast agents. PMID:26932775

  15. Investigating the low-dose limits of multidetector CT in lung nodule surveillance.

    Science.gov (United States)

    Paul, N S; Siewerdsen, J H; Patsios, D; Chung, T B

    2007-09-01

    The purpose of this study was to evaluate the factors limiting nodule detection in thoracic computed tomography (CT) and to determine whether prior knowledge of nodule size and attenuation, available from a baseline CT study, influences the minimum radiation dose at which nodule surveillance CT scans can be performed while maintaining current levels of nodule detectability. Multiple nodules varying in attenuation (-509 to + 110 HU) and diameter (1.6 to 9.5 mm) were layered in random and ordered sequences within 2 lung cylinders made of Rando lung material and suspended within a custom-built CT phantom. Multiple CT scans were performed at varying kVp (120, 100, and 80), mA (200, 150, 100, 50, 20, and 10), and beam collimation (5, 2.5, and 1.25 mm) on a four-row multidetector scanner (Lightspeed, General Electric, Milwaukee, WI) using 0.8 s gantry rotation. The corresponding range of radiation dose over which images were acquired was 0.3-26.4 mGy. Nine observers independently performed three specific tasks, namely: (1) To detect a 3.2 mm nodule of 23 HU; (2) To detect 3.2 mm nodules of varying attenuation (-509 to -154 HU); and (3) To detect nodules varying in size (1.6-9 mm) and attenuation (-509 to 110 HU). A two-alternative forced-choice test was used in order to determine the limits of nodule detection in terms of the proportion of correct responses (Pcorr, related to the area under the ROC curve) as a summary metric of observer performance. The radiation dose levels for detection of 99% of nodules in each task were as follows: Task 1 (1 mGy); Task 2 (5 mGy); and Task 3 (7 mGy). The corresponding interobserver confidence limits were 1, 5, and 10 mGy for Tasks 1, 2, and 3, respectively. There was a fivefold increase in the radiation dose required for detection of lower-density nodules (Tasks 1 to 2). Absence of prior knowledge of the nodule size and density (Task 3) corresponds to a significant increase in the minimum required radiation dose. Significant image

  16. Correlation of Color Doppler with Multidetector CT Angiography Findings in Carotid Artery Stenosis

    Directory of Open Access Journals (Sweden)

    Živorad N. Savic

    2010-01-01

    Full Text Available The aim of this paper was to examine the correlation between the Color Doppler ultrasound (CD-US and multidetector CT angiography (MDCTA diagnostic methods, and to define the degree and extent of stenosis in patients with internal carotid artery stenosis. This was a cross-sectional study with a consecutive series of patients. All US examinations were always carried out by the same physician-angiologist, while all CT examinations were always carried out by the same physician-radiologist. Both worked independently from each other. The stenosis area was measured at the narrowest point by NASCET criteria for US/CT. Peak systolic velocity (PSV over 210 cm/sec and end diastolic velocity (EDV over 110 cm/sec criteria were applied for stenoses with lumen narrowed over 70%, while PSV under 130 cm/sec and EDV under 100 cm/sec criteria were applied for those with lumen narrowed under 70%. A total of 124 carotid arteries were observed; namely, 89 narrowed and 68 surgically treated. All patients were reviewed by US and then by MDCTA; patients with 70–99% stenosis underwent surgery. The correlation coefficient between stenosis degree measured by US and MDCTA was 0.922; p 0.05. The US and CT matching level for stenoses from 70 to 99% was very high (κ = 0.778, p < 0.01. In conclusion, there is a highly significant statistical correlation among both diagnostic methods when measuring stenosis degree and extent. US is more dependent on the physician, while MDCTA is more objective and independent from the physician. We think it would be appropriate to undertake an MDCTA exam for those patients who are candidates for carotid endarterectomy.

  17. Multidetector computed tomography in abdominal emergencies; Multidetektor-CT bei abdominellen Notfaellen

    Energy Technology Data Exchange (ETDEWEB)

    Zorger, N.; Schreyer, A.G. [Universitaetsklinikum Regensburg (Germany). Institut fuer Roentgendiagnostik

    2009-06-15

    Abdominal emergencies encompass traumatic events in the region of the abdomen as well as the clinical term acute abdomen. Multidetector CT (MDCT) represents one of the most important imaging modalities for detection and correct diagnosis in such abdominal emergencies. Based on the acquired data MDCT allows a stable imaging of the abdomen in an extremely short time even in critically ill patients. Multiplanar reconstructions can be created based on the high resolution data allowing an impressive visualization of the pathology. In this review article the most important abdominal pathologies of the abdomen diagnosed by MDCT are presented with special emphasis on the liver, bile ducts, spleen and kidneys as well as the gastro-intestinal tract. Additionally, MDCT imaging of the individual organ regions will be dealt with in detail. (orig.) [German] Abdominelle Notfaelle beinhalten sowohl traumatische Ereignisse im Bereich des Bauchraums als auch den klinischen Begriff des ''akuten Abdomens''. Die Darstellung solcher Notfaelle mittels Multidetektor-Computertomographie (MDCT) ist eine leistungsfaehige Methode zur Detektion und richtigen Diagnosefindung der abdominellen Notfaelle. Die MDCT erlaubt eine stabile Bildgebung des Abdomens in extrem kurzer Zeit bei schwerkranken Patienten und zudem multiplanare Rekonstruktionen, basierend auf den akquirierten Rohdatensaetzen mit der Moeglichkeit, zusaetzlich Befunde anschaulicher zu visualisieren. In diesem Uebersichtsartikel werden die MDCT-Charakteristika verschiedener abdomineller Notfaelle der wichtigsten Organregionen des Abdomens, wie der Leber und der Gallenwege, des Pankreas, der Milz und der Niere sowie des Gastrointestinaltrakts erlaeutert. Dabei wird speziell auf die Multidetektor-CT-Technik der einzelnen Organregionen eingegangen. (orig.)

  18. Pancreatic adenocarcinomas without secondary signs on multiphasic multidetector CT: association with clinical and histopathologic features

    Energy Technology Data Exchange (ETDEWEB)

    Tamada, Tsutomu; Ito, Katsuyoshi; Sone, Teruki; Kanki, Akihiko; Higaki, Atsushi; Hayashida, Minoru; Yamamoto, Akira [Kawasaki Medical School, Departments of Radiology, Kurashiki City, Okayama (Japan); Kanomata, Naoki [Kawasaki Medical School, Department of Pathology, Kurashiki City, Okayama (Japan)

    2016-03-15

    To determine the clinical, histopathologic and imaging features of pancreatic adenocarcinomas without secondary signs on dynamic CT. Seventy patients (mean age 70 years) with histologically proven pancreatic adenocarcinoma underwent preoperative contrast material-enhanced multiphasic multidetector CT before pancreatic resection. In each patient, clinical data including carbohydrate antigen 19-9, frequency of isoattenuating tumours, and presence of secondary signs and histopathologic findings such as tumour location, tumour stage, and microscopic infiltrative growth grade were evaluated. Ten tumours (14 %) were without secondary signs, and 60 (86 %) were with secondary signs. Tumours without and with secondary signs were located in the uncinate process in 5 (50 %) and 3 (5 %), head in 3 (30 %) and 29 (48 %), body in 2 (20 %) and 22 (37 %), and tail in 0 (0 %) and 6 (10 %), respectively (p =.001). The frequency of isoattenuating pancreatic adenocarcinomas without secondary signs was significantly higher than those with secondary signs (p = 0.034). The tumour stage of pancreatic adenocarcinomas without secondary signs was earlier than that in tumours with secondary signs (p = 0.041). Pancreatic adenocarcinomas without secondary signs is characterized by the presence of uncinate and isoattenuating tumours and earlier tumour stage compared to tumours with secondary signs. (orig.)

  19. Contrast enhanced multi-detector CT and MR findings of a well-differentiated pancreatic vipoma

    Institute of Scientific and Technical Information of China (English)

    Luigi; Camera; Rosa; Severino; Antongiulio; Faggiano; Stefania; Masone; Gelsomina; Mansueto; Simone; Maurea; Rosa; Fonti; Marco; Salvatore

    2014-01-01

    Pancreatic vipoma is an extremely rare tumor accounting for less than 2% of endocrine pancreatic neoplasms with a reported incidence of 0.1-0.6 per million. While cross-sectional imaging findings are usually not specific, exact localization of the tumor by means of either computed tomography(CT) or magnetic resonance(MR) is pivotal for surgical planning. However, cross-sectional imaging findings are usually not specific and further characterization of the tumor may only be achieved bysomatostatin-receptor scintigraphy(SRS). We report the case of a 70 years old female with a two years history of watery diarrhoea who was found to have a solid, inhomogeneously enhancing lesion at the level of the pancreatic tail at Gadolinium-enhanced MR(Somatom Trio 3T, Siemens, Germany). The tumor had been prospectively overlooked at a contrast-enhanced multi-detector CT(Aquilion 64, Toshiba, Japan) performed after i.v. bolus injection of only 100 cc of iodinated non ionic contrast media because of a chronic renal failure(3.4 mg/mL) but it was subsequently confirmed by SRS. The patient first underwent a successful symptomatic treatment with somatostatin analogues and was then submitted to a distal pancreasectomy with splenectomy to remove a capsulated whitish tumor which turned out to be a well-differentiated vipoma at histological and immuno-histochemical analysis.

  20. Role of curved planar reformations using multidetector spiral CT in diagnosis of pancreatic and peripancreatic diseases

    Institute of Scientific and Technical Information of China (English)

    Jing-Shan Gong; Jian-Min Xu

    2004-01-01

    AIM: To investigate the role of curved planar reformations using multidetector spiral CT (MSCT) in diagnosis of pancreatic and peripancreatic diseases.METHODS: From October 2001 to September 2003, 47consecutive patients with pancreatic or peripancreatic diseases, which were confirmed by operation, endoscopic retrograde cholangiopancreatography and clinical follow-up,were enrolled in this study. CT scanning was performed at a MSCT with four rows of detector. A set of images with an effective thickness of 1.0-2.0 mm and a gap of 0.5-1.0 mm(50% overlap) were acquired in all patients for postprocessing. Curved planar reformations were carried out by drawing a curved line on transverse source images, coronal or sagittal multiplanar reformations according to certain anatomic structures (such as cholangiopancreatic ducts or peripancreatic vessels) and the position of lesion.RESULTS: With thin collimation, MSCT could acquire highquality curved planar reformations to display the profile of the whole pancreas, to trace the cholangiopancreatic ducts and peripancreatic vessels, and to show the relationship of lesions with pancreas and peripancreatic anatomic structures in one curved plane, which facilitates diagnosis and rapid communication of diagnostic information with referring physicians.CONCLUSION: MSCT with thin collimation could be used to create high-quality curved planar reformations in evaluating pancreatic and peripancreatic diseases with pertinent anatomic information and relative pathologic signs to facilitate the diagnosis and enhance communication with the referring physician. Curved planar reformations can serve as supplements for transverse images in diagnosis and management of pancreatic and peripancreatic diseases.

  1. Diagnosis of deep vein thrombosis using multi-detector helical CT

    Energy Technology Data Exchange (ETDEWEB)

    Kimura, Masashi; Minamiguchi, Hiroki; Sahara, Shinya [Wakayama Medical Coll. (Japan)] [and others

    2002-11-01

    The purpose of this study was to evaluate the usefulness of multi-detector helical CT (MDHCT) with contrast medium in the diagnosis of deep vein thrombosis (DVT). The bilateral veins of the dorsal pedis in 45 patients (12 men, 33 women; average age, 64 years) under clinical suspicion of DVT were first punctured using 22-G needles. Then CT scanning from the level of the foot to the inferior vena cava was started 20 sec after the initial injection of 200 mL of dilute contrast medium (50 mL nonionic iodinated contrast medium of 300 mgI/mL and 150 mL saline) at a rate of 5 mL/sec. Two patients were excluded because of unsuccessful venous puncture. The average scanning time in 43 patients was 38.5{+-}7.9 seconds. Images of veins from the foot to the inferior vena cava were clearly demonstrated in each case. MDHCT showed DVT in 32 cases and patent deep vein in 11 cases. Simultaneous venography of the lower extremity in 18 patients clearly visualized DVT at the same level detected by contrast MDHCT. MDHCT for the diagnosis of DVT has the advantages of wider scanning rage, shorter scanning time, and finer Z-axis resolution than the other diagnostic modalities. (author)

  2. Multidetector CT in the evaluation of potential living donors for liver transplantation.

    Science.gov (United States)

    Alonso-Torres, Ana; Fernández-Cuadrado, Jaime; Pinilla, Inmaculada; Parrón, Manuel; de Vicente, Emilio; López-Santamaría, Manuel

    2005-01-01

    Living donor liver transplantation is increasingly being used to help compensate for the increasing shortage of cadaveric liver grafts. However, the extreme variability of the hepatic vascular systems can impede this surgical procedure. Evaluation of potential living donors was conducted in which a two-detector-row computed tomographic (CT) scanner was used to obtain arterial phase and portal dominant phase images following the intravenous injection of contrast material, after which three-dimensional maximum-intensity-projection and volume-rendered images were created. The vascular anatomy was evaluated, with special attention given to the origin and course of the artery to segment IV and the presence of variants, especially those considered relative or absolute contraindications for donation, those requiring reconstruction, or those potentially altering the surgical approach. In addition, graft and remnant liver volumes were determined and the liver parenchyma evaluated. Multidetector CT is proving to be valuable in the evaluation of potential living liver donors, contributing to donor safety and providing comprehensive information about the hepatic vascular anatomy, the liver parenchyma, and graft and remnant liver volume. This information is critical in choosing the most suitable potential donor, in surgical planning, and in obtaining an optimal graft that maintains the balance between blood supply and venous drainage. PMID:16009821

  3. Optimised low-dose multidetector CT protocol for children with cranial deformity

    Energy Technology Data Exchange (ETDEWEB)

    Vazquez, Jose Luis [Complejo Hospitalario Universitario de Vigo, Department of Radiology, Vigo, Pontevedra (Spain); Pombar, Miguel Angel [Complejo Hospitalario Universitario de Santiago, Department of Radiophysics, Santiago de Compostela, La Coruna (Spain); Pumar, Jose Manuel [Complejo Hospitalario Universitario de Santiago, Department of Radiology, Santiago de Compostela, La Coruna (Spain); Campo, Victor Miguel del [Complejo Hospitalario Universitario de Vigo, Department of Public Health, Vigo, Pontevedra (Spain)

    2013-08-15

    To present an optimised low-dose multidetector computed tomography (MDCT) protocol for the study of children with cranial deformity. Ninety-one consecutive MDCT studies were performed in 80 children. Studies were performed with either our standard head CT protocol (group 1, n = 20) or a low-dose cranial deformity protocol (groups 2 and 3). Group 2 (n = 38), initial, and group 3 (n = 33), final and more optimised. All studies were performed in the same 64-MDCT equipment. Cranial deformity protocol was gradationally optimised decreasing kVp, limiting mA range, using automatic exposure control (AEC) and increasing the noise index (NI). Image quality was assessed. Dose indicators such us CT dose index volume (CTDIvol), dose-length product (DLP) and effective dose (E) were used. The optimised low-dose protocol reached the following values: 80 kVp, mA range: 50-150 and NI = 23. We achieved a maximum dose reduction of 10-22 times in the 1- to 12-month-old cranium in regard to the 2004 European guidelines for MDCT. A low-dose MDCT protocol that may be used as the first diagnostic imaging option in clinically selected patients with skull abnormalities. (orig.)

  4. Thrombosis and cancer: spectrum of multidetector CT findings in oncologic patients with thromboembolic disease. A pictorial review

    International Nuclear Information System (INIS)

    This article is a reasoned pictorial review illustrating the many faces of thrombotic and embolic disease developing in the cancer patient. From a clinical point of view, we particularly point out the importance of properly identifying this occurrence in its various presentations. From a radiological point of view, special emphasis is given to the wide spectrum of multidetector CT findings, to the clues of benign and malignant thrombus diagnosis, and to the potential interpretative pitfalls

  5. Thrombosis and cancer: spectrum of multidetector CT findings in oncologic patients with thromboembolic disease. A pictorial review

    Energy Technology Data Exchange (ETDEWEB)

    Catalano, Orlando; Lutio di Castelguidone, Elisabetta de; Gallipoli d' Errico, Adolfo (Dept. of Radiology, National Cancer Institute, Fondazione G Pascale, Naples (Italy)), email: orlandcat@tin.it; Nunziata, Antonio (Dept. of Radiology, S Bellone Centre, Naples (Italy))

    2011-09-15

    This article is a reasoned pictorial review illustrating the many faces of thrombotic and embolic disease developing in the cancer patient. From a clinical point of view, we particularly point out the importance of properly identifying this occurrence in its various presentations. From a radiological point of view, special emphasis is given to the wide spectrum of multidetector CT findings, to the clues of benign and malignant thrombus diagnosis, and to the potential interpretative pitfalls

  6. Comparison of effective dose for imaging of mandible between multi-detector CT and cone-beam CT

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Dae Kyo; Lee, Sang Chul; Huh, Kyung Hoe; Yi, Won Jin; Lee, Sam Sun; Choi, Soon Chul [School of Dentistry, Seoul National University, Seoul (Korea, Republic of)

    2012-06-15

    The aim of this study was to compare the effective dose for imaging of mandible between multi-detector computed tomography (MDCT) and cone-beam computed tomography (CBCT). An MDCT with low dose technique was also compared with them. Thermoluminescent dosimeter (TLD) chips were placed at 25 organ sites of an anthropomorphic phantom. The mandible of the phantom was exposed using 2 different types of MDCT units (Somatom Sensation 10 for standard-dose MDCT, Somatom Emotion 6 for low-dose MDCT) and 3 different CBCT units (AZ3000CT, Implagraphy, and Kavo 3D eXaM). The radiation absorbed dose was measured and the effective dose was calculated according to the ICRP 2007 report. The effective dose was the highest for Somatom Sensation 10 (425.84 {mu}Sv), followed by AZ3000CT (332.4 {mu}Sv), Somatom Emotion 6 (199.38 {mu}Sv), and 3D eXaM (111.6 {mu}Sv); it was the lowest for Implagraphy (83.09 {mu}Sv). The CBCT showed significant variation in dose level with different device. The effective doses of MDCTs were not significantly different from those of CBCTs for imaging of mandible. The effective dose of MDCT could be markedly decreased by using the low-dose technique.

  7. Cardiac Multidetector Computed Tomography: Basic Physics of Image Acquisition and Clinical Applications

    OpenAIRE

    Bardo, Dianna M.E; Brown, Paul

    2008-01-01

    Cardiac MDCT is here to stay. And, it is more than just imaging coronary arteries. Understanding the differences in and the benefits of one CT scanner from another will help you to optimize the capabilities of the scanner, but requires a basic understanding of the MDCT imaging physics. This review provides key information needed to understand the differences in the types of MDCT scanners, from 64 – 320 detectors, flat panels, single and dual source configurations, step and shoot prospective a...

  8. Evaluation of angiogenesis in colorectal carcinoma with multidetector-row CT multislice perfusion imaging

    Energy Technology Data Exchange (ETDEWEB)

    Feng Shiting, E-mail: fst1977@163.co [Department of Radiology, First Affiliated Hospital of SunYat-sen University, Guangzhou 510080 (China); Sun Canhui, E-mail: canhuisun@sina.co [Department of Radiology, First Affiliated Hospital of SunYat-sen University, Guangzhou 510080 (China); Li Ziping, E-mail: liziping163@tom.co [Department of Radiology, First Affiliated Hospital of SunYat-sen University, Guangzhou 510080 (China); Mak, Henry Ka-Fung, E-mail: makkf@hkucc.hku.h [Department of Diagnostic Radiology, University of Hong Kong, Hong Kong (China); Peng Zhenpeng, E-mail: ppzhen@21cn.co [Department of Radiology, First Affiliated Hospital of SunYat-sen University, Guangzhou 510080 (China); Guo Huanyi, E-mail: guohuanyi@163.co [Department of Radiology, First Affiliated Hospital of SunYat-sen University, Guangzhou 510080 (China); Meng Quanfei, E-mail: mzycoco@gmail.co [Department of Radiology, First Affiliated Hospital of SunYat-sen University, Guangzhou 510080 (China)

    2010-08-15

    To evaluate the correlation between 64 multidetector-row CT (64MDCT) perfusion imaging in colorectal carcinoma and microvessel density (MVD) and vascular endothelial growth factor (VEGF), 64MDCT perfusion imaging was performed in 33 patients with pathologically verified colorectal carcinoma. These images were analyzed with perfusion functional software, and time-density curves (TDC) were created for the region of interest (ROI) encompassing the tumor, the target artery and vein. The individual perfusion maps generated indicated blood flow (BF), blood volume (BV), mean transit time (MTT), and permeability-surface area product (PS). MVD and VEGF were evaluated by immunohistochemical staining with anti-CD34 and anti-VEGF, respectively. Correlations between MVD or VEGF with CT perfusion parameters and clinicopathological factors (Dukes' stages, invasion depth, and lymph node and liver metastasis) were also investigated. MVD in the colorectal carcinoma was 22.61 {+-} 9.01 per x200 field. The scores obtained for VEGF expression were 4.15 {+-} 1.09. VEGF staining was positive in 25 of 29 tumors (86.2%). There was no significant correlation between the presence of MVD, VEGF expression and clinicopathological factors (P > 0.05). There was also no correlation between MVD, VEGF expression, and any dynamic CT parameters (P > 0.05). The BV and MTT were significantly higher in tumors demonstrating serous coat invasion than in those without it (t = -2.63, -2.24, P = 0.0137, 0.0331, respectively). BV was also significantly correlated with tumor size (r = 0.41, P = 0.02). Neither BF nor PS was correlated with clinicopathological factors. In conclusion, 64MDCT perfusion imaging, MVD, and VEGF may reflect angiogenic activity, but no significant correlation among these factors.

  9. Multi-detector row CT scanning in Paleoanthropology at various tube current settings and scanning mode.

    Science.gov (United States)

    Badawi-Fayad, J; Yazbeck, C; Balzeau, A; Nguyen, T H; Istoc, A; Grimaud-Hervé, D; Cabanis, E- A

    2005-12-01

    The purpose of this study was to determine the optimal tube current setting and scanning mode for hominid fossil skull scanning, using multi-detector row computed tomography (CT). Four fossil skulls (La Ferrassie 1, Abri Pataud 1, CroMagnon 2 and Cro-Magnon 3) were examined by using the CT scanner LightSpeed 16 (General Electric Medical Systems) with varying dose per section (160, 250, and 300 mAs) and scanning mode (helical and conventional). Image quality of two-dimensional (2D) multiplanar reconstructions, three-dimensional (3D) reconstructions and native images was assessed by four reviewers using a four-point grading scale. An ANOVA (analysis of variance) model was used to compare the mean score for each sequence and the overall mean score according to the levels of the scanning parameters. Compared with helical CT (mean score=12.03), the conventional technique showed sustained poor image quality (mean score=4.17). With the helical mode, we observed a better image quality at 300 mAs than at 160 in the 3D sequences (P=0.03). Whereas in native images, a reduction in the effective tube current induced no degradation in image quality (P=0.05). Our study suggests a standardized protocol for fossil scanning with a 16 x 0.625 detector configuration, a 10 mm beam collimation, a 0.562:1 acquisition mode, a 0.625/0.4 mm slice thickness/reconstruction interval, a pitch of 5.62, 120 kV and 300 mAs especially when a 3D study is required. PMID:16211320

  10. Quantification in non-invasive cardiac imaging: CT and MR

    OpenAIRE

    Rossi, Alexia

    2013-01-01

    markdownabstract__Abstract__ The diagnosis and management of cardiac disease require a precise assessment of morphological and functional cardiac parameters. This thesis is divided in three parts. Part I emphasizes the role of cardiac computed tomography (CT) in the diagnosis of patients with ischemic heart disease. Part 2 describes the role of cardiac magnetic resonance (CMR) and cardiac CT in the diagnosis, interventional planning, and follow-up of patients with aortic valve stenosis. Part ...

  11. Multidetector CT imaging of mechanical prosthetic heart valves: quantification of artifacts with a pulsatile in-vitro model

    OpenAIRE

    Symersky, P.; Budde, R. P. J.; Westers, P.; Mol, de, B.A.J.M.; Prokop, M

    2011-01-01

    Objectives Multidetector computed tomography (MDCT) can detect the cause of prosthetic heart valve (PHV) dysfunction but is hampered by valve-induced artifacts. We quantified artifacts of four PHV using a pulsatile in-vitro model and assessed the relation to leaflet motion and valve design. Methods A Medtronic Hall tilting disc (MH), and Carbomedics (CM), St Jude (SJM), and ON-X bileaflet valves underwent CT in an in-vitro model using retrospective gating with a 64 detector CT system in stati...

  12. Detection, visualization and evaluation of anomalous coronary anatomy on 16-slice multidetector-row CT

    International Nuclear Information System (INIS)

    Early identification and evaluation of relatively frequent anomalous coronary anatomy is quite relevant because of the occurrence of sudden cardiac death or related symptoms of myocardial ischemia. Selective coronary angiography (CAG) is invasive, expensive and cannot always provide the required information adequately. Recently, non-invasive imaging techniques such as magnetic resonance imaging and multidetector-row computed tomography (MDCT) have been shown to provide a good anatomical view of the coronary artery tree. This study aims to demonstrate the value of 16-MDCT for evaluation of anomalous coronary anatomy. In 13 patients scanned using 16-MDCT, six different coronary anomalies were diagnosed [two absent left main, one single vessel left coronary artery (LCA), three LCA originating from the right (two with interarterial course), six right coronary artery originating from the left, one double left anterior descending (LAD)]. Mean diagnostic quality, recorded by two observers using a 5-point scale (1= non-diagnostic to 5= excellent diagnostic quality), resulted in a mean score of 3.73 (SD 1.19) without any non-diagnostic result. MDCT offers an accurate diagnostic modality to visualize the origin and course of anomalous coronary arteries by a three-dimensional display of anatomy. Shortcomings in CAG can be overcome by the use of contrast-enhanced MDCT. (orig.)

  13. Optimisation of vascular input and output functions in CT-perfusion imaging using 256(or more)-slice multidetector CT

    Energy Technology Data Exchange (ETDEWEB)

    Niesten, Joris M.; Schaaf, Irene C. van der; Riordan, Alan J.; Jong, Hugo W.A.M. de; Mali, Willem P.T.M.; Velthuis, Birgitta K. [University Medical Center Utrecht, Department of Radiology, Utrecht (Netherlands)

    2013-05-15

    To evaluate the accuracy and reproducibility of CT-perfusion (CTP) by finding the optimal artery for the arterial input function (AIF) and re-evaluating the necessity of the venous output function (VOF). Forty-four acute ischaemic stroke patients who underwent non-enhanced CT, CTP and CT-angiography using 256-slice multidetector computed tomography (MDCT) were evaluated. The anterior cerebral artery (ACA), middle cerebral artery (MCA), internal carotid artery (ICA) and basilar artery were selected as the AIF. Subsequently the resulting area under the time-enhancement curve of the AIF (AUC{sub AIF}) and quantitative perfusion measurements were analysed by repeated measures ANOVA and subsequently the paired t test. To evaluate reproducibility we examined if the VOF could be deleted by comparing the perfusion measurements using versus not using the VOF (paired t test). The AUC{sub AIF} and perfusion measurements resulting from the different AIFs showed significant group differences (all P < 0.0001). The ICA had the largest AUC{sub AIF} and resulted in the highest mean transient time (MTT) and lowest cerebral blood flow (CBF), whereas the basilar artery showed the lowest cerebral blood volume (CBV). Not using the VOF showed significantly higher CBV and CBF in 66 % of patients on the ipsilateral (P < 0.0001 and P = 0.007, respectively) and contralateral hemisphere (P < 0.0001 and P = 0.019, respectively). Selecting the ICA as the AIF and continuing the use of the VOF would improve the accuracy of CTP. (orig.)

  14. Multidetector-row spiral CT for detection of coronary artery stenosis

    International Nuclear Information System (INIS)

    Objective: To evaluate the feasibility and accuracy of multidetector-row spiral CT (MDCT) in the detection of coronary artery stenosis. Methods: Sixty-five consecutive patients with suspected coronary artery disease (CAD) underwent the retrospectively ECG-gated MDCT angiography for visualization of coronary artery lumen changes, and 32 of them were also investigated with selective coronary angiography (SCA). The images quality of MDCTA was analyzed. Presence and percentage of stenosis in coronary artery segments were determined. Results of determination of >50% stenosis of the vessel diameter with MDCTA were compared to the findings of SCA. Results: With MDCT angiography significant better image quality was achieved in patients with a heart rate below 70 beats per minute (W = 539, P50% stenosis with MDCTA were 95%, 80%, 89% and 90%, respectively. Conclusion: Even if its effective exposure time of 250 ms is limited by faster heart rates, MDCT is capable of achieving high image quality and high accuracy for detection of coronary artery stenosis

  15. ECG-gated multi-detector row CT for assessment of mitral valve disease: initial experience

    International Nuclear Information System (INIS)

    Our objective was to evaluate applicability and image quality of contrast-enhanced, retrospectively ECG-gated multi-detector row CT (MDCT) for visualization of anatomical details of the mitral valve and its apparatus, and to determine the value of MDCT for diagnosing abnormal findings of the mitral valve. Twenty consecutive patients with mitral valve disease underwent MDCT preoperatively. Two readers assessed visibility of the mitral valve annulus, mitral valve leaflets, tendinous cords, and papillary muscles by using a four-point Likert grading scale. Abnormal mitral valve findings [thickening of the mitral valve leaflets, presence of mitral annulus calcification (MAC), and calcification of the valvular leaflets] were compared with preoperative echocardiography and intraoperative findings. Visibility of the mitral valve annulus and mitral valve leaflets was good or excellent in 15 patients (75%) and in 19 patients (95%) for papillary muscles. The MDCT yielded a 95-100% agreement compared with echocardiography and surgery with regard to the assessment of mitral valve leaflet thickening and the presence of calcifications of the mitral valve annulus or mitral valve leaflets. Intermodality agreement between MDCT and echocardiography was excellent with regard to classification of mitral valve leaflet thickness (κ=1.00) and good regarding classification of MAC thickness (κ=0.73). Contrast-enhanced, retrospectively ECG-gated MDCT allows good to excellent visualization of anatomical details of the mitral valve and its apparatus, and demonstrates good agreement with echocardiography and surgery in diagnosing mitral valve abnormalities. (orig.)

  16. Optimal iodine dose for 3-dimensional multidetector-row CT angiography of the liver

    International Nuclear Information System (INIS)

    Purpose: To clarify the optimal iodine dose of contrast material for 3-dimensional multidetector-row CT angiography (3D-MDCTA) of the venous vasculature of the liver using volume rendering technique. Materials and methods: This study included 103 patients who were randomly assigned to 5 contrast-enhanced MDCT protocol groups with different body-weight-tailored doses of contrast material: 500, 600, 630, 650, and 700 mgI/kg body weight. The arterial, portal, and hepatic parenchymal phases were obtained to evaluate enhancement values of the aorta, portal vein, and hepatic vein. Visualization of the portal and hepatic veins on the volume-rendering images of 3D-MDCTA was evaluated using a 5-point grade. Dunnett's test was used to compare the mean enhancement value and mean grades of image quality (700 mgI/kg dose group was control). Results: The mean enhancement values of portal and hepatic vein in the group with 500 and 600 mgI/kg were significantly lower than those of the control group. During visual assessment, a significantly lower mean grades were observed in 500 mgI/kg groups for the portal vein, and 500 and 600 mgI/kg groups for hepatic vein. There were no significant intergroup differences in mean enhancement values and visual assessment among the groups using 630 mgI/kg or more. Conclusion: Iodine doses of 630 mgI/kg was recommended for 3D-MDCTA

  17. Optimized image reconstruction for detection of deep venous thrombosis at multidetector-row CT venography

    Energy Technology Data Exchange (ETDEWEB)

    Das, Marco; Muehlenbruch, Georg; Mahnken, Andreas Horst; Guenther, Rolf W.; Wildberger, Joachim Ernst [University Hospital, University of Technology (RWTH), Department of Diagnostic Radiology, Aachen (Germany); Weiss, Claudia [RWTH Aachen, Institute of Medical Statistics, Aachen (Germany); Schoepf, U. Joseph [Medical University of South Carolina, Department of Radiology, Charleston, SC (United States); Leidecker, Christianne [Institute of Medical Physics, University of Erlangen, Erlangen (Germany)

    2006-02-01

    The aims of this study were to optimize image quality for indirect CT venography (sequential versus spiral), and to evaluate different image reconstruction parameters for patients with suspected deep venous thrombosis (DVT). Fifty-one patients (26/25 with/without DVT) were prospectively evaluated for pulmonary embolism (PE) with standard multidetector-row computed tomography (MDCT) protocols. Retrospective image reconstruction was done with different slice thicknesses and reconstruction increments in sequential and spiral modes. All reconstructions were read for depiction of DVT and to evaluate best reconstruction parameters in comparison with the thinnest reconstruction (''gold standard''). Image noise and venous enhancement were measured as objective criteria for image quality. Subjective image quality was rated on a four-point scale. Effective dose was estimated for all reconstructions. In sequential 10/50 reconstruction DVT was completely detected in 13/26 cases, partially in 10/26 cases and was not detected at all in 3/26 cases, and 15/26, 9/26 and 2/26 cases for the 10/20 reconstruction, respectively. DVT was completely detected in all spiral reconstructions. Image noise ranged between 14.8-29.1 HU. Median image quality was 2. Estimated effective dose ranged between 2.3 mSv and 11.8 mSv. Gaps in sequential protocols may lead to false negative results. Therefore, spiral scanning protocols for complete depiction of DVT are mandatory. (orig.)

  18. Impact of multidetector CT-angiography on the emergency management of severe hemoptysis

    Energy Technology Data Exchange (ETDEWEB)

    Chalumeau-Lemoine, Ludivine [Service de Pneumologie et Réanimation, Hôpital Tenon, HUEP, APHP, 4 rue de la Chine, 75020 Paris (France); Khalil, Antoine, E-mail: antoine_khalil@yahoo.fr [Service de Radiologie, Hôpital Tenon, HUEP, APHP, 4 rue de la Chine, 75020 Paris (France); Pathological Angiogenesis and Vessel Normalization, Center for Interdisciplinary Research in Biology, CNRS UMR 7241/INSERM U1050, Collège de France, Paris (France); Prigent, Hélène [Service de Pneumologie et Réanimation, Hôpital Tenon, HUEP, APHP, 4 rue de la Chine, 75020 Paris (France); Carette, Marie-France [Service de Radiologie, Hôpital Tenon, HUEP, APHP, 4 rue de la Chine, 75020 Paris (France); Université Pierre et Marie Curie, Paris VI (France); Fartoukh, Muriel [Service de Pneumologie et Réanimation, Hôpital Tenon, HUEP, APHP, 4 rue de la Chine, 75020 Paris (France); Université Pierre et Marie Curie, Paris VI (France); Parrot, Antoine [Service de Pneumologie et Réanimation, Hôpital Tenon, HUEP, APHP, 4 rue de la Chine, 75020 Paris (France)

    2013-11-01

    Background: Multidetector CT-angiography (MDCTA) is commonly used in patients with severe haemoptysis requiring admission to intensive care unit. However, the impact of MDCTA on the management of severe haemoptysis in emergency setting is poorly evaluated. Methods: We prospectively compared data provided by clinical bedside evaluation (clinical examination, chest-X-ray and fiberoptic bronchoscopy) to MDCTA data in terms of lateralization, location of the bleeding site, etiology as well as impact on the treatment choice. Results: Over a 13-month period, 87 patients (men n = 58, median age = 61 years, median haemoptysis expectorated volume = 180 mL) were included. Etiology was mainly (67%) bronchiectasis, tuberculosis sequelae and tumor. MDCTA and clinical bedside evaluation were equally effective in determining lateralization (87.4% and 93.1%, respectively, p = 0.23) and location (85% and 82.7%, respectively, p = 0.82) of the bleeding site. MDCTA was significantly more accurate than the clinical bedside strategy in determining the haemoptysis cause (86% and 70%, respectively, p = 0.007). Moreover, MDCTA suggested the involvement of systemic arteries as bleeding mechanism in 92% of cases, leading to the modification of the treatment initially considered after bedside evaluation in 21.8% of patients. Conclusion: MDCTA provides useful information for the management of patients with severe haemoptysis, especially in the treatment choice. Thus, in the absence of emergency fiberoptic bronchoscopy (FOB) requirement for airways management, MDCTA should be the first-line procedure performed in emergency clinical setting.

  19. New absorbed dose measurement with cylindrical water phantoms for multidetector CT

    International Nuclear Information System (INIS)

    The aim of this study was to develop new dosimetry with cylindrical water phantoms for multidetector computed tomography (MDCT). The ionization measurement was performed with a Farmer ionization chamber at the center and four peripheral points in the body-type and head-type cylindrical water phantoms. The ionization was converted to the absorbed dose using a 60Co absorbed-dose-to-water calibration factor and Monte Carlo (MC) -calculated correction factors. The correction factors were calculated from MDCT (Brilliance iCT, 64-slice, Philips Electronics) modeled with GMctdospp (IMPS, Germany) software based on the EGSnrc MC code. The spectrum of incident x-ray beams and the configuration of a bowtie filter for MDCT were determined so that calculated photon intensity attenuation curves for aluminum (Al) and calculated off-center ratio (OCR) profiles in air coincided with those measured. The MC-calculated doses were calibrated by the absorbed dose measured at the center in both cylindrical water phantoms. Calculated doses were compared with measured doses at four peripheral points and the center in the phantom for various beam pitches and beam collimations. The calibration factors and the uncertainty of the absorbed dose determined using this method were also compared with those obtained by CTDIair (CT dose index in air). Calculated Al half-value layers and OCRs in air were within 0.3% and 3% agreement with the measured values, respectively. Calculated doses at four peripheral points and the centers for various beam pitches and beam collimations were within 5% and 2% agreement with measured values, respectively. The MC-calibration factors by our method were 44–50% lower than values by CTDIair due to the overbeaming effect. However, the calibration factors for CTDIair agreed within 5% with those of our method after correction for the overbeaming effect. Our method makes it possible to directly measure the absorbed dose for MDCT and is more robust and accurate than the

  20. Multi-detector CT angiography for lower gastrointestinal bleeding: can it select patients for endovascular intervention?

    International Nuclear Information System (INIS)

    Full text: This is a retrospective review of the results at our institution of using multi-detector CT angiography (CTA) to localise lower gastrointestinal (GI) bleeding. We hypothesised that in our patient population: (i) CTA was unlikely to demonstrate bleeding in patients who were haemodynamically stable; (ii) in haemodynamically unstable patients in whom CTA was undertaken, the results could be used to select patients who would benefit from catheter angiography; and (iii) in haemodynamically unstable patients in whom CTA was undertaken, a subgroup of patients could be identified who would benefit from primary surgical treatment, avoiding invasive angiography completely. A retrospective review was conducted of the clinical records of all patients undergoing CTA for lower GI haemorrhage at our institution between 1 January 2005 and 30 June 2007. Out of the 20 patients examined, 10 had positive CTAs demonstrating the bleeding site. Nine were haemodynamically unstable at the time of the study. Four patients with positive CT angiograms were able to be treated directly with surgery and avoided invasive angiography. Ten patients had negative CTAs. Four of these were haemodynamically unstable, six haemodynamically stable. Only one required intervention to secure haemostasis, the rest stopped spontaneously. No haemodynamically stable patient who had a negative CTA required intervention. CTA is a useful non-invasive technique for localising the site of lower GI bleeding. In our patient population, in the absence of haemodynamic instability, the diagnostic yield of CTA was low and bleeding was likely to stop spontaneously. In haemodynamically unstable patients, a positive CTA allowed patients to be triaged to surgery or angiography, whereas there was a strong association between a negative CTA and spontaneous cessation of bleeding.

  1. Carotid artery wall thickness: comparison between sonography and multi-detector row CT angiography

    Energy Technology Data Exchange (ETDEWEB)

    Saba, Luca [University of Cagliari, Department of Radiology, Policlinico Universitario, Cagliari (Italy); Sanfilippo, Roberto; Montisci, Roberto [Policlinico Universitario, Department of Vascular Surgery, Cagliari (Italy); Mallarini, Giorgio [University of Cagliari, Department of Radiology, Policlinico Universitario, Cagliari (Italy); Ospedale San Giovanni di Dio, Institute of Radiology, Cagliari (Italy)

    2010-02-15

    Prospective studies have shown that an increased thickness of the carotid wall is a significant predictor of coronary and cerebrovascular complications. Our purpose was to assess the agreement between multi-detector row computed tomography (CT) angiography (MDCTA) and colour Doppler ultrasound (CD-US) in measuring carotid artery wall thickness (CAWT) and the intima-media thickness (IMT). Altogether, 97 subjects (age range 64-84 years) were prospectively analysed using a four-detector row CT and a sonographic scanner. In total, 46 subjects had shown cerebral ischaemic symptoms. CAWT and IMT were measured in each patient using MDCTA and CD-US (by applying a digital calliper), respectively. Continuous data were described as the mean value {+-} standard deviation and were compared using the Mann-Whitney U test. A p value <0.05 was considered significant. Bland-Altman statistics was employed to measure the agreement between MDCTA and CD-US. CAWT ranged from 0.5 to 1.53 mm, with a mean value of 0.9072 mm. IMT ranged from 0.46 to 1.5 mm, with a mean value of 0.8839 mm. By analysing the Bland-Altman plot, we observed an excellent agreement between CD-US and MDCTA with a bias between methods of 0.023 {+-} 0.0424 mm. A limit of agreement from -0.06 to 0.106 was recorded. Correlation coefficient r was 0.9855 (95% confidence interval 0.9808-0.989). Mann-Whitney U test indicated a p value of 0.377. Obtained results indicated a significant agreement between MDCTA and CD-US in the measurement of CAWT and IMT. (orig.)

  2. Carotid artery wall thickness: comparison between sonography and multi-detector row CT angiography

    International Nuclear Information System (INIS)

    Prospective studies have shown that an increased thickness of the carotid wall is a significant predictor of coronary and cerebrovascular complications. Our purpose was to assess the agreement between multi-detector row computed tomography (CT) angiography (MDCTA) and colour Doppler ultrasound (CD-US) in measuring carotid artery wall thickness (CAWT) and the intima-media thickness (IMT). Altogether, 97 subjects (age range 64-84 years) were prospectively analysed using a four-detector row CT and a sonographic scanner. In total, 46 subjects had shown cerebral ischaemic symptoms. CAWT and IMT were measured in each patient using MDCTA and CD-US (by applying a digital calliper), respectively. Continuous data were described as the mean value ± standard deviation and were compared using the Mann-Whitney U test. A p value <0.05 was considered significant. Bland-Altman statistics was employed to measure the agreement between MDCTA and CD-US. CAWT ranged from 0.5 to 1.53 mm, with a mean value of 0.9072 mm. IMT ranged from 0.46 to 1.5 mm, with a mean value of 0.8839 mm. By analysing the Bland-Altman plot, we observed an excellent agreement between CD-US and MDCTA with a bias between methods of 0.023 ± 0.0424 mm. A limit of agreement from -0.06 to 0.106 was recorded. Correlation coefficient r was 0.9855 (95% confidence interval 0.9808-0.989). Mann-Whitney U test indicated a p value of 0.377. Obtained results indicated a significant agreement between MDCTA and CD-US in the measurement of CAWT and IMT. (orig.)

  3. Evaluation of bone substitute materials: comparison of flat-panel based volume CT to conventional multidetector CT.

    Science.gov (United States)

    Sauerbier, Sebastian; Duttenhoefer, Fabian; Sachlos, Elefterios; Haberstroh, Jörg; Scheifele, Christian; Wrbas, Karl-Thomas; Voss, Pit Jacob; Veigel, Egle; Smedek, Jörg; Ganter, Philip; Tuna, Taskin; Gutwald, Ralf; Palmowski, Moritz

    2013-10-01

    Over the last decade tissue engineering has emerged as a key factor in bone regeneration within the field of cranio-maxillofacial surgery. Despite this in vivo analysis of tissue-engineered-constructs to monitor bone rehabilitation are difficult to conduct. Novel high-resolving flat-panel based volume CTs (fp-VCT) are increasingly used for imaging bone structures. This study compares the potential value of novel fp-VCT with conventional multidetector CT (MDCT) based on a sheep sinus floor elevation model. Calcium-hydroxyapatite reinforced collagen scaffolds were populated with autologous osteoblasts and implanted into sheep maxillary sinus. After 8, 16 and 24 weeks MDCT and fp-VCT scans were performed to investigate the volume of the augmented area; densities of cancellous and compact bone were assessed as comparative values. fp-VCT imaging resulted in higher spatial resolution, which was advantageous when separating closely related anatomical structures (i.e. trabecular and compact bone, biomaterials). Fp-VCT facilitated imaging of alterations occurring in test specimens over time. fp-VCTs therefore displayed high volume coverage, dynamic imaging potential and superior performance when investigating superfine bone structures and bone remodelling of biomaterials. Thus, fp-VCTs may be a suitable instrument for intraoperative imaging and future in vivo tissue-engineering studies.

  4. Image quality in multidetector CT of the paranasal sinuses. Potential of dose reduction using an adaptive post-processing filter

    International Nuclear Information System (INIS)

    Purpose: Evaluation of subjective image quality in dose-reduced multi-detector CT (MDCT) of paranasal sinuses using a 2D non-linear adaptive post-processing filter (2D-NLAF). Materials and Methods: MDCT of paranasal sinuses was simulated using a human head phantom at a Somatom Sensation Cardiac 64 (Siemens, Erlangen). At constant collimation (64 x 0.6 mm) und pitch (p = 1), the tube current (50, 100, 200 mAs) and tube potential (80, 100, 120 kVp) were modified. The radiation exposure was represented by CTDIvol. Four independent blinded radiologists evaluated the image quality of axial 2 mm images and coronal reformations concerning the assessment of 'fractures' and 'soft tissue processes'. The subjective image quality of original and post-processed images using a 2D-NLAF (SharpViewCT registered, Sweden) was graded on a 5-point scale ('1' excellent - '5' not adequate) and compared. Results: Compared to the protocol with the best image quality (120kVp/ 200 mAs) 2D-NLAF led to a significant improvement in the subjective image quality at 100 kVp/ 100 mAs (score '1.4' with filter versus '2.2' without) and 120 kVp/ 50 mAs ('1.6' versus '2.0') (p < 0.03) particularly for high contrasts ('fractures', p < 0.001). In 'soft tissue processes', 2D-NLAF provided improved quality from '2.1' to '1.4' (p < 0.04) at 100 kVp/ 100 mAs. Down to a CTDIvol of 8 mGy, the image quality was rated 'good', and down to 5 mGy 'diagnostic'. Conclusion: The phantom study indicates a dose reduction potential in MDCT of paranasal sinuses up to 58 % compared to a standard dose protocol using a 2D-NLAF without an essential loss of image quality. 2D-NLAF is particularly effective at 100 kVp/ 100 mAs and 120 kVp/ 50 mAs. (orig.)

  5. Multi-detector CT enterography with iso-osmotic mannitol as oral contrast for detecting small bowel disease

    Institute of Scientific and Technical Information of China (English)

    Lian-He Zhang; Shi-Zheng Zhang; Hong-Jie Hu; Min Gao; Ming Zhang; Qian Cao; Qiao-wei Zhang

    2005-01-01

    AIM: To assess the feasibility and usefulness of multi-detector CT enterography with orally administered iso-osmotic mannitol as negative contrast in demonstrating small bowel disease.METHODS: Thirteen volunteers and 38 patients with various kinds of small bowel disease were examined. We administered about 1 500 mL iso-osmotic mannitol as negative contrast agent and then proceeded with helical CT scanning on a Siemens Sensation 16 scanner. All volunteers and patients were interviewed about their tolerance of the procedure. Two radiologists postprocessed imaging data with MPR, thin MIP, VRT and INSPACE when necessary and then interpreted the scans,and adequacy of luminal distention was evaluated on a four-point scale. Demonstration of features of various kinds of small bowel disease was analyzed.RESULTS: The taste of iso-osmotic mannitol is good (slightly sweet) and acceptable by all. Small bowel distention was excellent and moderate in most volunteers and patients. CT features of many kinds of diseases such as tumors, Crohn's disease,and small bowel obstruction,etc. were clearly displayed.CONCLUSION: Multi-detector CT enterography with iso-osmotic mannitol as negative contrast to distend the small bowel is a simple, rapid, noninvasive and effective method of evaluating small bowel disease.

  6. Improving Image Quality of On-Board Cone-Beam CT in Radiation Therapy Using Image Information Provided by Planning Multi-Detector CT: A Phantom Study

    OpenAIRE

    Yang, Ching-Ching; Chen, Fong-Lin; Lo, Yeh-Chi

    2016-01-01

    Purpose The aim of this study was to improve the image quality of cone-beam computed tomography (CBCT) mounted on the gantry of a linear accelerator used in radiation therapy based on the image information provided by planning multi-detector CT (MDCT). Methods MDCT-based shading correction for CBCT and virtual monochromatic CT (VMCT) synthesized using the dual-energy method were performed. In VMCT, the high-energy data were obtained from CBCT, while the low-energy data were obtained from MDCT...

  7. 64-slice multidetector coronary CT angiography: in vitro evaluation of 68 different stents

    Energy Technology Data Exchange (ETDEWEB)

    Maintz, David; Seifarth, Harald; Rink, Michael; Oezguen, Murat; Heindel, Walter; Fischbach, Roman [University of Muenster, Department of Clinical Radiology, Muenster (Germany); Raupach, Rainer; Flohr, Thomas [Siemens Medical Solutions, Forchheim (Germany); Sommer, Torsten [University of Bonn, Department of Radiology, Bonn (Germany)

    2006-04-15

    The purpose of this study was to test a large sample of different coronary artery stents using four image reconstruction approaches with respect to lumen visualization, lumen attenuation, and image noise in 64-slice multidetector-row computed tomography (MDCT) in vitro and to provide a catalogue of currently used coronary artery stents when imaged with state-of the-art MDCT. We examined 68 different coronary artery stents (57 stainless steel, four cobalt-chromium, one cobalt-alloy, two nitinol, four tantalum) in a coronary artery phantom (vessel diameter 3 mm, intravascular attenuation 250 HU, extravascular density -70). Stents were imaged in axial orientation with standard parameters: 32x0.6 collimation, pitch 0.24, 680 mAs, 120 kV, rotation time 0.37 s. Four different image reconstructions were obtained with varying convolution kernels and section thicknesses: (1) soft, 0.6 mm, (2) soft, 0.75, (3) medium soft, 0.6, and (4) stent-optimized sharp, 0.6. To evaluate visualization characteristics of of the stent, the lumen diameter, intraluminal density and noise were measured. The high-resolution kernel offered significantly better average lumen visualization (57% {+-}10%) and more realistic lumen attenuation (222 HU {+-}66 HU) at the expense of increased noise (15.3 HU {+-}3.7 HU) compared with the soft and medium-soft CT angiography (CTA) protocol (p<0.001 for all). Stents with a lumen visibility of more than 66% were: Arthos pico, Driver, Flex, Nexus2, S7, Tenax complete, Vision (all 67%), Symbiot, Teneo (70%), and Radius (73%). Only ten stents showed a lumen visibility of less than 50%. Stent lumen visibility largely varies depending on the stent type. Even with the improved spatial resolution of 64-slice CT, a stent-optimized kernel remains beneficial for stent visualization when compared with the standard medium-soft CTA protocol. Using 64-slice CT and high-resolution kernel, the majority of stent products show a lumen visibility of more than 50% of the stent

  8. Measuring temporal resolution of cardiac CT reconstructions

    Science.gov (United States)

    Matthews, David; Heuscher, Dominic

    2005-04-01

    Multi-slice CT today is capable of imaging the heart with excellent temporal resolution. Algorithms have been developed to perform reconstructions combining data from multiple cardiac cycles. This paper presents a simulation phantom that enables a direct measurement of the actual temporal resolution achieved by these algorithms. This is not only useful for assessing the temporal resolution but also for validating the algorithms themselves. A simulation phantom was developed that consists of a 20 cm. diameter water phantom containing an array of cylinders whose intensities are pulsed for various durations ranging from 10 msec. to 250 msec. The intensity varied between the background value of water (0 HU) and 800 HU. By measuring the nominal attenuation value at the center of each cylinder, a curve can be derived representing the response over the given temporal range. A temporal resolution representing the FWHM value is determined based on the half-max value of this curve. Reconstructions were performed using a multi-cycle cardiac algorithm described previously in the literature. The measured FWHM values agree quite well to the temporal resolution predicted by the cardiac algorithm itself. Even the variation along the longitudinal axis can be accounted for by the predicted values. A simulated phantom can be used to accurately assess the temporal resolution of cardiac reconstruction algorithms. Excellent agreement was achieved between the predicted and measured temporal resolution values for the multi-cycle algorithm used in this study.

  9. Cardiac MRI and CT features of inheritable and congenital conditions associated with sudden cardiac death

    Energy Technology Data Exchange (ETDEWEB)

    Sparrow, Patrick; Merchant, Naeem; Provost, Yves; Doyle, Deirdre; Nguyen, Elsie; Paul, Narinder [University Health Network and Mount Sinai Hospital, Division of Cardiothoracic Imaging, Department of Medical Imaging, Toronto, Ontario (Canada)

    2009-02-15

    Cardiac MRI (CMR) and electrocardiogram (ECG)-gated multi-detector computed tomography (MDCT) are increasingly important tools in the identification and assessment of cardiac-related disease processes, including those associated with sudden cardiac death (SCD). While the commonest cause of SCD is coronary artery disease (CAD), in patients under 35 years inheritable cardiomyopathies such as hypertrophic cardiomyopathy and arrhythmogenic right ventricular cardiomyopathy are important aetiologies. CMR in particular offers both accurate delineation of the morphological abnormalities associated with these and other conditions and the possibility for risk stratification for development of ventricular arrhythmias with demonstration of macroscopic scar by delayed enhancement imaging with intravenous gadolinium. (orig.)

  10. A method of estimating conceptus doses resulting from multidetector CT examinations during all stages of gestation

    International Nuclear Information System (INIS)

    Purpose: Current methods for the estimation of conceptus dose from multidetector CT (MDCT) examinations performed on the mother provide dose data for typical protocols with a fixed scan length. However, modified low-dose imaging protocols are frequently used during pregnancy. The purpose of the current study was to develop a method for the estimation of conceptus dose from any MDCT examination of the trunk performed during all stages of gestation. Methods: The Monte Carlo N-Particle (MCNP) radiation transport code was employed in this study to model the Siemens Sensation 16 and Sensation 64 MDCT scanners. Four mathematical phantoms were used, simulating women at 0, 3, 6, and 9 months of gestation. The contribution to the conceptus dose from single simulated scans was obtained at various positions across the phantoms. To investigate the effect of maternal body size and conceptus depth on conceptus dose, phantoms of different sizes were produced by adding layers of adipose tissue around the trunk of the mathematical phantoms. To verify MCNP results, conceptus dose measurements were carried out by means of three physical anthropomorphic phantoms, simulating pregnancy at 0, 3, and 6 months of gestation and thermoluminescence dosimetry (TLD) crystals. Results: The results consist of Monte Carlo-generated normalized conceptus dose coefficients for single scans across the four mathematical phantoms. These coefficients were defined as the conceptus dose contribution from a single scan divided by the CTDI free-in-air measured with identical scanning parameters. Data have been produced to take into account the effect of maternal body size and conceptus position variations on conceptus dose. Conceptus doses measured with TLD crystals showed a difference of up to 19% compared to those estimated by mathematical simulations. Conclusions: Estimation of conceptus doses from MDCT examinations of the trunk performed on pregnant patients during all stages of gestation can be made

  11. Paratracheal air cysts: prevalence and correlation with lung disease using multi-detector CT

    International Nuclear Information System (INIS)

    The purpose of this study was to determine the prevalence of paratracheal air cysts (PACs), their correlation with different lung diseases and their connection with the trachea by chest multi detector computed tomography (MDCT). We retrospectively reviewed chest MDCT images of 8240 consecutive patients obtained from January 2010 to December 2011 with a 16-detector multi-detector CT scanner. PACs were assessed for prevalence, location, level, size and the presence of visible communication with the trachea. MDCT diagnoses were classified as normal, primary or metastatic malignancies, chronic obstructive pulmonary disease (COPD), pneumonia and other lung diseases. We randomly selected 330 patients who had no visible PACs for the control group. We evaluated the associations between patients' demographic findings (age and sex), MDCT findings of lung and the presence of PACs. The findings of the PACs and control groups were compared. Statistical analysis used chi-squared test and Mann - Whitney U-test for evaluation. PACs were presented in 301 patients (4%); 204 men and 97 women, ranging in age from 14 to 91 years (median=57 years). There was no significant difference in the presence of PACs by age (P>0.05). Male subjects showed higher prevalence (P=0.005). Fifty PACs (16.6%) showed communication with the trachea or main bronchus. Although the relation between COPD and PACs was statistically significant (P<0.001), there was no relation between primary or metastatic malignancies, pneumonia and other lung diseases and PACs. PACs are common in MDCT and should not be misdiagnosed as pneumomediastinum. It should be kept in mind that PACs may be associated with COPD.

  12. Role of multidetector CT angiography in the evaluation of suspected mesenteric ischemia

    International Nuclear Information System (INIS)

    Objective: To assess the role of multidetector CT angiography (MDCTA) in the diagnosis of acute mesenteric ischemia (AMI) and to compare the diagnostic utility of axial images with reconstructed images. Materials and methods: In this Institute Review Board approved prospective study, MDCTA was performed on 31 patients who presented with the clinical suspicion of AMI (25M; 6F, age range: 16–73 years). Axial and reconstructed images of each patient were evaluated independently by two radiologists for evidence of bowel wall thickening, abnormal mucosal enhancement, bowel dilatation or obstruction, mesenteric stranding, ascites, solid organ infarcts, pneumatosis intestinalis or porto-mesenteric gas, and mesenteric arterial or venous occlusion. MDCT findings were correlated with the surgical findings and clinical outcome. Patients were later divided into two groups: a study group of patients with proven AMI and a control group of patients with an alternate diagnosis, for the purpose of statistical analysis. Results: AMI was correctly diagnosed in all 16 patients on MDCTA (100% sensitivity and specificity) of whom nine patients underwent surgical exploration. Three patients expired before surgery and the remaining 5 patients were proven based on positive clinical and laboratory findings. Mesenteric arterial occlusion was seen in 7 patients while 5 patients had portomesenteric venous thrombosis. Reconstructed images using minimum intensity projection, volume rendering and multiplanar volume reconstruction were found to perform better for the detection of vascular abnormalities and improved the diagnostic confidence of both radiologists in the evaluation of bowel and mesenteric abnormalities. Conclusion: MDCTA is an effective non-invasive modality for the diagnosis of mesenteric ischemia.

  13. The quality of reconstructed 3D images in multidetector-row helical CT: experimental study involving scan parameters

    International Nuclear Information System (INIS)

    To determine which multidetector-row helical CT scanning technique provides the best-quality reconstructed 3D images, and to assess differences in image quality according to the levels of the scanning parameters used. Four objects with different surfaces and contours were scanned using multidetector-row helical CT at three detector-row collimations (1.25, 2.50, 5.00 mm), two pitches (3.0, 6.0), and three different degrees of overlap between the reconstructed slices (0%, 25%, 50%). Reconstructed 3D images of the resulting 72 sets of data were produced using volumetric rendering. The 72 images were graded on a scale from 1 (worst) to 5 (best) for each of four rating criteria, giving a mean score for each criterion and an overall mean score. Statistical analysis was used to assess differences in image quality according to scanning parameter levels. The mean score for each rating criterion, and the overall mean score, varied significantly according to the scanning parameter levels used. With regard to detector-row collimation and pitch, all levels of scanning parameters gave rise to significant differences, while in the degree of overlap of reconstructed slices, there were significant differences between overlap of 0% and of 50% in all levels of scanning parameters, and between overlap of 25% and of 50% in overall accuracy and overall mean score. Among the 18 scanning sequences, the highest score (4.94) was achieved with 1.25 mm detector-row collimation, 3.0 pitch, and 50% overlap between reconstructed slices. Comparison of the quality of reconstructed 3D images obtained using multidetector-row helical CT and various scanning techniques indicated that the 1.25 mm, 3.0, 50% scanning sequence was best. Quality improved as detector-row collimation decreased; as pitch was reduced from 6.0 to 3.0; and as overlap between reconstructed slices increased

  14. Prenatal diagnosis of chondrodysplasia punctata tibia-metacarpal type using multidetector CT and three-dimensional reconstruction

    Energy Technology Data Exchange (ETDEWEB)

    Miyazaki, Osamu [National Centre for Child Health and Development, Department of Radiology, Tokyo (Japan); Nishimura, Gen [Tokyo Metropolitan Kiyose Children' s Hospital, Department of Radiology, Tokyo (Japan); Sago, Haruhiko; Watanabe, Noriyoshi; Ebina, Shunsuke [National Centre for Child Health and Development, Department of Perinatal Medicine and Maternal Care, Tokyo (Japan)

    2007-11-15

    We report a case of chondrodysplasia punctata tibia-metacarpal type (CDP-TM) that was diagnosed prenatally using multidetector CT (MDCT) with three-dimensional (3-D) CT reconstructions. Prenatal US had shown severe thoracic hypoplasia and rhizomelic shortening of the limbs, raising the suspicion of thanatophoric dysplasia. However, MDCT showed punctate calcifications in the epiphyseal cartilage of the humeri and femora, carpal bones, and paravertebral region. On 3-D CT, the tibiae were much shorter than the fibulae, the humeri were very short and bowed, and severe platyspondyly was evident. These findings led to the diagnosis of CDP-TM. The diagnosis was confirmed on postnatal radiographs. Prenatal MDCT with 3-D images may make a useful contribution to prenatal diagnosis in selected fetuses with severe skeletal dysplasia. (orig.)

  15. Calcified pulmonary thromboembolism in a child with sickle cell disease: value of multidetector CT in patients with acute chest syndrome

    International Nuclear Information System (INIS)

    The incidence of pulmonary embolism in children is not clearly known, but is believed to be low. Risk factors for pulmonary thromboembolism include central venous catheter, malignancy, surgery, infection, trauma, and congenital hypercoagulable disorders. Children with sickle cell disease are prothrombotic and are at an increased risk of thromboembolism. The incidence of this event is unknown because these children are often not thoroughly imaged. We report here a case of a calcified pulmonary thromboembolism in a child with sickle cell disease and emphasize the use of multidetector CT in detection of pulmonary thromboembolism in children with sickle cell disease. (orig.)

  16. Calcified pulmonary thromboembolism in a child with sickle cell disease: value of multidetector CT in patients with acute chest syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Staser, Jonathan A. [Indiana University Medical Center, Department of Radiology, Indianapolis, IN (United States); Alam, Tariq [Medical College of Ohio, Department of Radiology, Toledo, OH (United States); Applegate, Kimberly [Indiana University Medical Center, Sections of Pediatric Radiology and Health Services Research, Indianapolis, IN (United States); Indiana University Medical Center, Department of Radiology, Riley Hospital for Children, Indianapolis, IN (United States)

    2006-06-15

    The incidence of pulmonary embolism in children is not clearly known, but is believed to be low. Risk factors for pulmonary thromboembolism include central venous catheter, malignancy, surgery, infection, trauma, and congenital hypercoagulable disorders. Children with sickle cell disease are prothrombotic and are at an increased risk of thromboembolism. The incidence of this event is unknown because these children are often not thoroughly imaged. We report here a case of a calcified pulmonary thromboembolism in a child with sickle cell disease and emphasize the use of multidetector CT in detection of pulmonary thromboembolism in children with sickle cell disease. (orig.)

  17. Multi-detector row CT in the assessment of axillary lymph node metastasis in breast cancer

    International Nuclear Information System (INIS)

    The purpose of this study is to evaluate the diagnostic capability instead of clinical efficacy of multi-detector row CT (MDCT) in the assessment of axillary lymph node metastasis in breast cancer. MDCT was performed in 63 patients with breast cancer, and multiplanar reformation (MPR) and volume rendering (VR) images were reconstructed for the evaluation of bilateral axillary lymph nodes. Two hundred sixty eight lymph nodes were depicted with MDCT, and correlation with pathological findings was performed. The short axis length of lymph node was measured on MPR image, and the shape of the nodes was analyzed with the pathological results statistically. The diagnostic criteria on size and shape of lymph node metastasis were discussed Dynamic study with contrast media was also performed, and the CT value ratios (CTVR) of the lymph nodes and breast tumors were calculated. No relevance of axillary lymph node metastasis was noted to the pathological types of breast cancer. The average short axis length of the ipsilateral axillary nodes was 8.9 mm±3.8 (SD) while that of the contralateral nodes was 4.9 mm±1.1 (SD) showing significant difference. More than 6.5 mm in short length of the lymph node was thought to be an effective criterion for positive metastasis, and its sensitivity was 96%. Soybean-shape lymph node was statistically common in metastasis, while non-metastatic nodes were commonly demonstrated as letter ''c'' shape or ring-like shape. Statistical relevance was obtained between the CTVR of axillary lymph nodes and that of breast tumors, suggesting clinical usefulness of dynamic study using contrast media in the evaluation of lymph node metastasis. With MPR and VR images using MDCT, more accurate morphological evaluation of axillary lymph nodes was possible. When soybean-shape node with more than 6.5 mm in short axis is depicted in the axillar region on MDCT metastasis should be the consideration. Comparison with the contralateral side as a control in coronal

  18. Quantification in non-invasive cardiac imaging: CT and MR

    NARCIS (Netherlands)

    A. Rossi (Alexia)

    2013-01-01

    markdownabstract__Abstract__ The diagnosis and management of cardiac disease require a precise assessment of morphological and functional cardiac parameters. This thesis is divided in three parts. Part I emphasizes the role of cardiac computed tomography (CT) in the diagnosis of patients with ische

  19. Multidetector CT findings of splenic artery aneurysm in children with chronic liver disease

    International Nuclear Information System (INIS)

    Splenic artery aneurysm (SAA) is a well-known complication of chronic liver disease and portal hypertension in adults. The incidence of SAA in children undergoing selective hepatic angiography prior to liver transplantation is reported as 4%, but there are few systematic studies. To investigate the SAAs detected by multidetector CT angiography (MDCTA) among children with chronic liver disease. A total of 124 children (71 girls, 53 boys; mean age 118 months; age range 5 days to 204 months) with chronic liver disease underwent MDCTA to display the vascular anatomy and any vascular complications during the pretransplantation period. Of these children, 23 also underwent coeliac angiography. The digital subtraction angiography (DSA) and MDCTA findings were compared. SAAs were detected in 13 children (10.4%); none was detectable by US. All patients had more than one aneurysm; ten patients had more than three. In all except one patient, the SAAs were located only in the intraparenchymal branches of the splenic artery; in one patient they were located in the intraparenchymal segment and in the distal third of the splenic artery. The mean size of the aneurysms was 6.5 mm (range 2.5-18 mm). All patients with aneurysms had splenomegaly and vascular collaterals. Nine of the children with SAAs had portal vein pathologies (two occlusions, two stenoses, five dilatations). A statistically significant difference existed with regard to the size of spleen (P < 0.05) and patient age (P < 0.05) between children with SAAs and children without SAAs. There was an increased risk of SAAs in patients with portal vein pathologies. In 19 patients without SAAs on MDCTA, no SAAs were seen on DSA. It is likely that the incidence of SAA in children with chronic liver disease will increase with improved survival of children with long-standing portal hypertension and chronic liver disease. MDCTA with multiplanar reconstruction is a noninvasive and effective means of imaging paediatric patients with

  20. Angiographic frequency of blunt cerebrovascular injury in patients with carotid canal or vertebral foramen fractures on multidetector CT

    Energy Technology Data Exchange (ETDEWEB)

    McKinney, Alexander [Department of Radiology, Hennepin County and University of Minnesota-Fairview and Medical Centers, Minneapolis, MN (United States)]. E-mail: mckin022@umn.edu; Ott, Frederick [Department of Radiology, Hennepin County and University of Minnesota-Fairview and Medical Centers, Minneapolis, MN (United States); Short, James [Department of Radiology, Hennepin County and University of Minnesota-Fairview and Medical Centers, Minneapolis, MN (United States); McKinney, Zeke [Department of Radiology, Hennepin County and University of Minnesota-Fairview and Medical Centers, Minneapolis, MN (United States); Truwit, Charles [Department of Radiology, Hennepin County and University of Minnesota-Fairview and Medical Centers, Minneapolis, MN (United States)

    2007-06-15

    Purpose: Blunt carotid injuries (BCI's) and blunt vertebral artery injuries (BVI's), known jointly as BCVI's, are common in 'high risk' patients. The purpose is to evaluate the rate of occurrence of BCI/BVI in patients screened purely by the radiologic criteria of fracture through the carotid canal or vertebral transverse foramina, or significant cervical subluxation, noted by multidetector CT. Methods: Seventy-one patients with 108 catheterized vessels were included over a 13-month interval. The angiographic examinations were prompted by current hospital protocol, solely by the presence of fractures involving/adjacent to the carotid canal, cervical fractures involving/adjacent to the foramen transversarium, or cervical fractures with significant subluxation. The incidence of each grade of blunt injury was calculated after review of the CT scans and catheter angiograms by two neuroradiologists. Results: Two thousand and seventy-three total blunt trauma admissions occurred during the time period, with a BCVI rate of 0.92-1.0% (depending on the reviewer), similar to previous studies. Mean time to catheter angiography was 16.6 h. Of the 71 included patients, there were 11-12 BCI's and 10-12 BVI's, an overall rate of 27-30% of BCVI in the patients with foraminal fractures. Interobserver agreement in reviewing the catheter angiograms was excellent (Kappa 0.795). Of note, three internal carotid pseudoaneurysms resolved spontaneously after anticoagulation or aspirin. Conclusion: This study confirms that there is a high rate of BCVI in the presence of carotid canal or vertebral foramen fractures that are noted by multidetector CT. Utilization of purely radiologic criteria of foraminal involvement may be a significant screening tool in the decision of whether to evaluate these patients acutely by catheter or CT angiography, and for early detection of patients at risk for symptomatology, to initiate prompt, prophylactic treatment.

  1. Value of cardiac 320-multidetector computed tomography and cardiac magnetic resonance imaging for assessment of myocardial perfusion defects in patients with known chronic ischemic heart disease

    DEFF Research Database (Denmark)

    Qayyum, Abbas Ali; Kühl, Jørgen T; Mathiasen, Anders B;

    2013-01-01

    The challenge for therapies targeting perfusion abnormalities is to identify and evaluate the region of interest. The aim of this study was to compare rest and stress myocardial perfusion measured by cardiac multi-detector computed tomography (MDCT) and cardiac magnetic resonance (CMR) imaging...... in patients with invasive coronary angiography demonstrated occluded vessels. Twenty-four patients with refractory angina due to occluded coronary arteries underwent perfusion imaging obtained by 320-MDCT scanner and 1.5 T MR scanner. Rest and adenosine stress images were obtained and interpreted using......) or 1 (abnormal). The summed rest and stress scores were calculated. MDCT and CMR had a high probability to identify perfusion defects. An excellent correlation between MDCT and CMR summed rest (r = 0.916) and stress scores (r = 0.915) was found. The interobserver reproducibility was high for MDCT...

  2. A pictorial review of acute aortic syndrome: discriminating and overlapping features as revealed by ECG-gated multidetector-row CT angiography

    OpenAIRE

    Ueda, Takuya; Chin, Anne; Petrovitch, Ivan; Fleischmann, Dominik

    2012-01-01

    Background The term "acute aortic syndrome" (AAS) encompasses a spectrum of life-threatening conditions characterized by acute aortic pain. AAS traditionally embraces three abnormalities including classic aortic dissection, intramural haematoma, and penetrating atherosclerotic ulcer. Although the underlying etiologies and conditions predisposing to AAS are diverse, the clinical features are indistinguishable. Methods Multidetector-row computed tomography (CT) with electrocardiographic gating ...

  3. Intravenous three-dimensional CT portography using multi-detector row CT in patients with hepatic cirrhosis. Evaluation of scan timing and image quality

    International Nuclear Information System (INIS)

    The purpose of this study was to evaluate the scan timing and image quality of intravenous three-dimensional (3D) CT portography using multi-detector row CT (MDCT) and to assess the influence of patients' body weight on enhancement of the portal vein (PV). One hundred nine patients with hepatic cirrhosis underwent triple-phase contrast enhanced CT using MDCT. The early, portal, and late phases were started at 30 sec, 60 sec, and 90 sec, respectively, after the beginning of intravenous injection of contrast medium (300 mgI/mL, 100 mL total). The CT value of the PV was assessed in the three phases: precontrast, portal phase, and late phase. 3D-portography of the MIP image was evaluated by three-point scale based on vessel visualization. The relationship between these data and body weight was investigated. The mean CT value of PV at 60 sec was 172.01±25.94 HU, which was significantly higher than that at 90 sec. Good or excellent 3D-CT portography was obtained in 97/109 patients (89%). Heavy patients tended to show less opacification of PV. Intravenous 3D-CT portography using MDCT at a 60 sec delay provided adequate PV images for patients with hepatic cirrhosis. Enhancement of PV was affected by patients' body weight. (author)

  4. Cardiac CT angiography in children with congenital heart disease

    Energy Technology Data Exchange (ETDEWEB)

    Siripornpitak, Suvipaporn, E-mail: ssiripornpitak@yahoo.com [Division of Diagnostic Radiology, Department of Diagnostic and Therapeutic Radiology, Faculty of Medicine, Ramathibodi Hospital, Mahidol University, Bangkok (Thailand); Pornkul, Ratanaporn [Division of Diagnostic Radiology, Department of Diagnostic and Therapeutic Radiology, Faculty of Medicine, Ramathibodi Hospital, Mahidol University, Bangkok (Thailand); Khowsathit, Pongsak [Pediatric Cardiac Unit, Department of Pediatrics, Faculty of Medicine, Ramathibodi Hospital, Mahidol University, Bangkok (Thailand); Layangool, Thanarat; Promphan, Worakan [Pediatric Cardiology Unit, Queen Sirikit National Institute of Child Health, Bangkok (Thailand); Pongpanich, Boonchob [Pediatric Cardiac Unit, Department of Pediatrics, Faculty of Medicine, Ramathibodi Hospital, Mahidol University, Bangkok (Thailand)

    2013-07-15

    Cardiac imaging plays an important role in both congenital and acquired heart diseases. Cardiac computed tomography (angiography) cCT(A) is a non-invasive, increasingly popular, complementary modality to echocardiography in evaluation of congenital heart diseases (CHD) in children. Despite radiation exposure, cCT(A) is now commonly used for evaluation of the complex CHD, giving information of both intra-cardiac and extra-cardiac anatomy, coronary arteries, and vascular structures. This review article will focus on the fundamentals and essentials for performing cCT(A) in children, including radiation dose awareness, basic techniques, and strengths and weaknesses of cCT(A) compared with cardiac magnetic resonance imaging (cMRI), and applications. The limitations of this modality will also be discussed, including the CHD for which cMRI may be substituted.

  5. Computed tomography angiography of carotid and coronary artery via a single-bolus injection protocol: a feasibility study using 320-row multidetector CT

    International Nuclear Information System (INIS)

    To investigate the feasibility of using a single-dose injection protocol in CT angiography (CTA) of the carotid and coronary artery with 320-row multidetector CT. A total of 82 consecutive patients with suspected carotid artery disease underwent an original CTA protocol aiming at capturing the extra-cranial carotid arteries and coronary arteries simultaneously using 320-row MDCT. The image quality, attenuation, and CNRs of the carotid and coronary arteries were assessed. The lag time (between two separated volumetric acquisitions) was compared between patients with and without cardiac venous opacification (CVO). The contrast medium volume and radiation dose were recorded. The image quality was 99.4 % diagnostic in carotid and 86.9 % in coronary artery segments. The mean attenuation of carotid and coronary arteries ranged from 462.2 Hu to 533.7 Hu, 415.9 Hu to 454.7 Hu respectively. The mean CNR of the carotid and coronary artery ranged from 15.8 to 18.9 and 17.7 to 20.4 respectively. The lag time in patients with and without CVO was 5.75 ± 1.64 s vs. 4.21 ± 1.14 s (p < 0.05). The mean radiation dose was 6.6 ± 4.1 mSv.The mean contrast media volume was 71.9 ± 9.1 ml. The carotid and coronary artery can be imaged simultaneously via our original single-dose injection CTA protocol using 320-row CT with adequate image quality. (orig.)

  6. Computed tomography angiography of carotid and coronary artery via a single-bolus injection protocol: a feasibility study using 320-row multidetector CT

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, WeiGuo [The First Affiliated Hospital of Soochow University, Department of Radiology, SuZhou (China); Fudan University, Department of Radiology, Zhongshan Hospital, Shanghai (China); Jin, Hang; Chen, Gang; Chen, Wenfang; Gu, Junying; Zeng, Mengsu [Fudan University, Department of Radiology, Zhongshan Hospital, Shanghai (China)

    2014-07-15

    To investigate the feasibility of using a single-dose injection protocol in CT angiography (CTA) of the carotid and coronary artery with 320-row multidetector CT. A total of 82 consecutive patients with suspected carotid artery disease underwent an original CTA protocol aiming at capturing the extra-cranial carotid arteries and coronary arteries simultaneously using 320-row MDCT. The image quality, attenuation, and CNRs of the carotid and coronary arteries were assessed. The lag time (between two separated volumetric acquisitions) was compared between patients with and without cardiac venous opacification (CVO). The contrast medium volume and radiation dose were recorded. The image quality was 99.4 % diagnostic in carotid and 86.9 % in coronary artery segments. The mean attenuation of carotid and coronary arteries ranged from 462.2 Hu to 533.7 Hu, 415.9 Hu to 454.7 Hu respectively. The mean CNR of the carotid and coronary artery ranged from 15.8 to 18.9 and 17.7 to 20.4 respectively. The lag time in patients with and without CVO was 5.75 ± 1.64 s vs. 4.21 ± 1.14 s (p < 0.05). The mean radiation dose was 6.6 ± 4.1 mSv.The mean contrast media volume was 71.9 ± 9.1 ml. The carotid and coronary artery can be imaged simultaneously via our original single-dose injection CTA protocol using 320-row CT with adequate image quality. (orig.)

  7. Evaluation of image quality and radiation dose at prospective ECG-triggered axial 256-slice multi-detector CT in infants with congenital heart disease

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Mei-ping; Liang, Chang-hong; Zhao, Zhen-jun; Liu, Hui; Li, Jing-lei; Zhang, Jin-e; Cui, Yan-hai; Yang, Lin; Liu, Qi-shun [Guangdong Academy of Medical Sciences, Guangdong General Hospital, Department of Radiology, Guangzhou (China); Ivanc, Thomas B.; Vembar, Mani [Philips Healthcare, CT Clinical Science, Highland Heights, OH (United States)

    2011-07-15

    There are a limited number of reports on the technical and clinical feasibility of prospective electrocardiogram (ECG)-gated multi-detector computed tomography (MDCT) in infants with congenital heart disease (CHD). To evaluate image quality and radiation dose at weight-based low-dose prospectively gated 256-slice MDCT angiography in infants with CHD. From November 2009 to February 2010, 64 consecutive infants with CHD referred for pre-operative or post-operative CT were included. All were scanned on a 256-slice MDCT system utilizing a low-dose protocol (80 kVp and 60-120 mAs depending on weight: 60 mAs for {<=}3 kg, 80 mAs for 3.1-6 kg, 100 mAs for 6.1-10 kg, 120 mAs for 10.1-15 kg). No serious adverse events were recorded. A total of 174 cardiac deformities, confirmed by surgery or heart catheterization, were studied. The sensitivity of MDCT for cardiac deformities was 97.1%; specificity, 99.4%; accuracy, 95.9%. The mean heart rate during scan was 136.7 {+-} 14.9/min (range, 91-160) with a corresponding heart rate variability of 2.8 {+-} 2.2/min (range, 0-8). Mean scan length was 115.3 {+-} 11.7 mm (range, 93.6-143.3). Mean volume CT dose index, mean dose-length product and effective dose were 2.1 {+-} 0.4 mGy (range, 1.5-2.8), 24.7 {+-} 5.9 mGy.cm (range, 14.7-35.8) and 1.6 {+-} 0.3 mSv (range, 1.1-2.5), respectively. Diagnostic-quality images were achieved in all cases. Satisfactory diagnostic quality for visualization of all/proximal/distal coronary artery segments was achieved in 88.4/98.8/80.0% of the scans. Low-dose prospectively gated axial 256-slice CT angiography is a valuable tool in the routine clinical evaluation of infants with CHD, providing a comprehensive three-dimensional evaluation of the cardiac anatomy, including the coronary arteries. (orig.)

  8. Breath-hold CT attenuation correction for quantitative cardiac SPECT

    OpenAIRE

    Koshino, Kazuhiro; Fukushima, Kazuhito; Fukumoto, Masaji; Sasaki, Kazunari; Moriguchi, Tetsuaki; Hori, Yuki; Zeniya, Tsutomu; Nishimura, Yoshihiro; Kiso, Keisuke; Iida, Hidehiro

    2012-01-01

    Background Attenuation correction of a single photon emission computed tomography (SPECT) image is possible using computed tomography (CT)-based attenuation maps with hybrid SPECT/CT. CT attenuation maps acquired during breath holding can be misaligned with SPECT, generating artifacts in the reconstructed images. The purpose of this study was to investigate the effects of respiratory phase during breath-hold CT acquisition on attenuation correction of cardiac SPECT imaging. Methods A series o...

  9. Volumetric Measurements of Lung Nodules with Multi-Detector Row CT: Effect of Changes in Lung Volume

    International Nuclear Information System (INIS)

    To evaluate how changes in lung volume affect volumetric measurements of lung nodules using a multi-detector row CT. Ten subjects with asthma or chronic bronchitis who had one or more lung nodules were included. For each subject, two sets of CT images were obtained at inspiration and at expiration. A total of 33 nodules (23 nodules ≥3 mm) were identified and their volume measured using a semiautomatic volume measurement program. Differences between nodule volume on inspiration and expiration were compared using the paired t-test. Percent differences, between on inspiration and expiration, in nodule attenuation, total lung volume, whole lung attenuation, and regional lung attenuation, were computed and compared with percent difference in nodule volume determined by linear correlation analysis. The difference in nodule volume observed between inspiration and expiration was significant (p < 0.01); the mean percent difference in lung nodule volume was 23.1% for all nodules and for nodules ≥3 mm. The volume of nodules was measured to be larger on expiration CT than on inspiration CT (28 out of 33 nodules; 19 out of 23 nodules ≥3 mm). A statistically significant correlation was found between the percent difference of lung nodule volume and lung volume or regional lung attenuation (p < 0.05) for nodules ≥3 mm. Volumetric measurements of pulmonary nodules were significantly affected by changes in lung volume. The variability in this respiration-related measurement should be considered to determine whether growth has occurred in a lung nodule

  10. Evaluation of the effective dose and image quality of low-dose multi-detector CT for orthodontic treatment planning

    International Nuclear Information System (INIS)

    This study was designed to compare the effective doses from low-dose and standard-dose multi-detector CT (MDCT) scanning protocols and evaluate the image quality and the spatial resolution of the low-dose MDCT protocols for clinical use. 6-channel MDCT scanner (Siemens Medical System, Forschheim, Germany), was used for this study. Protocol of the standard-dose MDCT for the orthodontic analysis was 130 kV, 35 mAs, 1.25 mm slice width, 0.8 pitch. Those of the low-dose MDCT for orthodontic analysis and orthodontic surgery were 110 kV, 30 mAs, 1.25 mm slice width, 0.85 pitch and 110 kV, 45 mAs, 2.5 mm slice width, 0.85 pitch. Thermoluminescent dosimeters (TLDs) were placed at 31 sites throughout the levels of adult female ART head and neck phantom. Effective doses were calculated according to ICRP 1990 and 2007 recommendations. A formalin-fixed cadaver and AAPM CT performance phantom were scanned for the evaluation of subjective image quality and spatial resolution. Effective doses in μSv (E2007) were 699.1, 429.4 and 603.1 for standard-dose CT of orthodontic treatment, low-dose CT of orthodontic analysis, and low-dose CT of orthodontic surgery, respectively. The image quality from the low-dose protocol were not worse than those from the standard-dose protocol. The spatial resolutions of both standard-dose and low-dose CT images were acceptable. From the above results, it can be concluded that the low-dose MDCT protocol is preferable in obtaining CT images for orthodontic analysis and orthodontic surgery.

  11. Multidetector CT diagnosis of massive hemobilia due to gallbladder polyposis in a child with metachromatic leukodystrophy

    Energy Technology Data Exchange (ETDEWEB)

    Wanner, Matthew R.; Karmazyn, Boaz [Indiana University School of Medicine, Riley Hospital for Children, Department of Radiology and Imaging Sciences, Indianapolis, IN (United States); Fan, Rong [Indiana University School of Medicine, Riley Hospital for Children, Department of Pathology and Laboratory Medicine, Indianapolis, IN (United States)

    2015-12-15

    Hemobilia secondary to gallbladder polyposis is rare in children but has been reported in a few children with metachromatic leukodystrophy. We present a case with preoperative multidetector computed tomography (MDCT) diagnosis of massive hemobilia caused by gallbladder polyposis in a patient with metachromatic leukodystrophy. Our report highlights the importance of both awareness of the association of gallbladder polyposis with other syndromes such as metachromatic leukodystrophy as well as the possibility of this entity presenting with life-threatening bleeding. (orig.)

  12. Multidetector CT diagnosis of massive hemobilia due to gallbladder polyposis in a child with metachromatic leukodystrophy

    International Nuclear Information System (INIS)

    Hemobilia secondary to gallbladder polyposis is rare in children but has been reported in a few children with metachromatic leukodystrophy. We present a case with preoperative multidetector computed tomography (MDCT) diagnosis of massive hemobilia caused by gallbladder polyposis in a patient with metachromatic leukodystrophy. Our report highlights the importance of both awareness of the association of gallbladder polyposis with other syndromes such as metachromatic leukodystrophy as well as the possibility of this entity presenting with life-threatening bleeding. (orig.)

  13. Is It Possible to Predict Heart Rate and Range during Enhanced Cardiac CT Scan from Previous Non-enhanced Cardiac CT?

    OpenAIRE

    Horiguchi, Jun; Yamamoto, Hideya; Arie, Ryuichi; Kiguchi, Masao; Fujioka, Chikako; Ohtaki, Megu; Kihara, Yasuki; Awai, Kazuo

    2010-01-01

    The effect of heart rate and variation during cardiac computed tomography (CT) on the examination quality. The purpose of this study is to investigate whether it is possible to predict heart rate and range during enhanced cardiac computed CT scan from previous non-enhanced cardiac CT scan. Electrocardiograph (ECG) files from 112 patients on three types of cardiac 64-slice CT (non-enhanced, prospective ECG-triggered and retrospective ECG-gated enhanced scans) were recorded. The mean heart rate...

  14. Multidetector row computed tomography of acute pancreatitis: Utility of single portal phase CT scan in short-term follow up

    Energy Technology Data Exchange (ETDEWEB)

    Kwon, Yongwonn [Department of Radiology, Konkuk University Medical Center, 4-12, Hwayang-dong, Gwangjin-gu, Seoul 143-729 (Korea, Republic of); Park, Hee Sun, E-mail: heesun.park@gmail.com [Department of Radiology, Konkuk University Medical Center, 4-12, Hwayang-dong, Gwangjin-gu, Seoul 143-729 (Korea, Republic of); Kim, Young Jun; Jung, Sung Il; Jeon, Hae Jeong [Department of Radiology, Konkuk University Medical Center, 4-12, Hwayang-dong, Gwangjin-gu, Seoul 143-729 (Korea, Republic of)

    2012-08-15

    Objective: The purpose of this study is to evaluate the question of whether nonenhanced CT or contrast enhanced portal phase CT can replace multiphasic pancreas protocol CT in short term monitoring in patients with acute pancreatitis. Materials and methods: This retrospective study was approved by the Institutional Review Board. From April 2006 to May 2010, a total of 52 patients having acute pancreatitis who underwent initial dual phase multidetector row CT (unenhanced, arterial, and portal phase) at admission and a short term (within 30 days) follow up dual phase CT (mean interval 10.3 days, range 3-28 days) were included. Two abdominal radiologists performed an independent review of three sets of follow up CT images (nonenhanced scan, single portal phase scan, and dual phase scan). Interpretation of each image set was done with at least 2-week interval. Radiologists evaluated severity of acute pancreatitis with regard to pancreatic inflammation, pancreatic necrosis, and extrapancreatic complication, based on the modified CT severity index. Scores of each image set were compared using a paired t-test and interobserver agreement was evaluated using intraclass correlation coefficient statistics. Results: Mean scores of sum of CT severity index on nonenhanced scan, portal phase scan, and dual phase scan were 5.7, 6.6, and 6.5 for radiologist 1, and 5.0, 5.6, and 5.8 for radiologist 2, respectively. In both radiologists, contrast enhanced scan (portal phase scan and dual phase scan) showed significantly higher severity score compared with that of unenhanced scan (P < 0.05), while portal phase and dual phase scan showed no significant difference each other. The trend was similar regarding pancreatic inflammation and extrapancreatic complications, in which contrast enhanced scans showed significantly higher score compared with those of unenhanced scan, while no significant difference was observed between portal phase scan and dual phase scan. In pancreatic necrosis

  15. Coronary imaging quality in routine ECG-gated multidetector CT examinations of the entire thorax: preliminary experience with a 64-slice CT system in 133 patients

    Energy Technology Data Exchange (ETDEWEB)

    Delhaye, Damien; Remy-Jardin, Martine; Salem, Randa; Teisseire, Antoine; Khalil, Chadi; Remy, Jacques [Hospital Calmette, University Center of Lille, Department of Thoracic Imaging, Lille Cedex (France); Delannoy-Deken, Valerie; Duhamel, Alain [University of Lille, Department of Medical Statistics, Lille Cedex (France)

    2007-04-15

    To evaluate image quality in the assessment of the coronary arteries during routine ECG-gated multidetector CT (MDCT) of the chest. One hundred and thirty three patients in sinus rhythm underwent an ECG-gated CT angiographic examination of the entire chest without {beta}-blockers with a 64-slice CT system. In 127 patients (95%), it was possible to assess the coronary arteries partially or totally; coronary artery imaging failed in six patients (5%), leading to a detailed description of the coronary arteries in 127 patients. Considering ten coronary artery segments per patient, 75% of coronary segments were assessable (948/1270 segments). When the distal segments were excluded from the analysis (i.e., seven coronary segments evaluated per patient), the percentage of assessable segments was 86% (768/889 proximal and mid coronary segments) and reached 93% (474/508) when assessing proximal segments exclusively. The mean number of assessable segments was significantly higher in patients with a heart rate {<=}80 bpm (n=95) than in patients with a heart rate >80 bpm (n=38) (p<0.002). Proximal and mid-coronary segments can be adequately assessed during a whole-chest ECG-gated CT angiographic examination without administration of {beta}-blockers in patients with a heart rate below 80 bpm. (orig.)

  16. The in vivo relationship between cross-sectional area and CT dose index in abdominal multidetector CT with automatic exposure control

    Energy Technology Data Exchange (ETDEWEB)

    Meeson, S; Alvey, C M; Golding, S J, E-mail: stuart.meeson@nds.ox.ac.u [Radiology Group, Nuffield Department of Surgery, University of Oxford, John Radcliffe Hospital, Oxford OX3 9DU (United Kingdom)

    2010-06-15

    The relationship between patient cross-sectional area and both volume CT dose index (CTDI) and dose length product was explored for abdominal CT in vivo, using a 16 multidetector row CT (MDCT) scanner with automatic exposure control. During a year-long retrospective survey of patients with MDCT for symptoms of abdominal sepsis, cross-sectional areas were estimated using customised ellipses at the level of the middle of vertebra L3. The relationship between cross-sectional area and the exposure parameters was explored. Scans were performed using a LightSpeed 16 (GE Healthcare Medical Systems, Milwaukee, WI) operated with tube current modulation. From a survey of 94 patients it was found that the CTDI increased with the increase in patient cross-sectional area. The relationship was logarithmic rather than linear, with a least-squares fit to the data (R{sup 2} = 0.80). For abdominal CT the cross-sectional area gave a measure of patient size based on the region of the body to be exposed. Exposure parameters increased with increasing cross-sectional area and the greater radiation exposure of larger patients was partly a consequence of their size. Given increasing obesity levels we believe that cross-sectional area and scan length should be added to future dose surveys, allowing patient size to be considered as a factor of relevance when examining population doses.

  17. Monte Carlo simulations in multi-detector CT (MDCT) for two PET/CT scanner models using MASH and FASH adult phantoms

    Energy Technology Data Exchange (ETDEWEB)

    Belinato, W., E-mail: wbfisica@gmail.com [Bahia Federal Institute of Education, Science and Technology – IFBA, Vitória da Conquista, 45.100-000 (Brazil); Department of Physics, Federal University of Sergipe – UFS, São Cristóvão, 49.100-000 (Brazil); Santos, W.S. [Department of Physics, Federal University of Sergipe – UFS, São Cristóvão, 49.100-000 (Brazil); Paschoal, C.M.M., E-mail: cinthiam.paschoal@gmail.com [Department of Civil Engineering, Vale do Acarau State University – UVA, Sobral 62.040-730 (Brazil); Souza, D.N. [Department of Physics, Federal University of Sergipe – UFS, São Cristóvão, 49.100-000 (Brazil)

    2015-06-01

    The combination of positron emission tomography (PET) and computed tomography (CT) has been extensively used in oncology for diagnosis and staging of tumors, radiotherapy planning and follow-up of patients with cancer, as well as in cardiology and neurology. This study determines by the Monte Carlo method the internal organ dose deposition for computational phantoms created by multidetector CT (MDCT) beams of two PET/CT devices operating with different parameters. The different MDCT beam parameters were largely related to the total filtration that provides a beam energetic change inside the gantry. This parameter was determined experimentally with the Accu-Gold Radcal measurement system. The experimental values of the total filtration were included in the simulations of two MCNPX code scenarios. The absorbed organ doses obtained in MASH and FASH phantoms indicate that bowtie filter geometry and the energy of the X-ray beam have significant influence on the results, although this influence can be compensated by adjusting other variables such as the tube current–time product (mAs) and pitch during PET/CT procedures.

  18. Multidetector-Row CT Angiography of Cerebral Vasospasm after Aneurysmal Subarachnoid Hemorrhage: Comparison of Bone Subtraction and Standard CT Angiography with Digital Subtraction Angiography

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Yong Hee; You, Jin Jong; Choi, Ho Cheol; Kim, Ji Eun [Dept. of Radiology, Gyeongsang National University Hospital, Jinju (Korea, Republic of); Choi, Dae Seob [Gyeongsang Institue of Health Science, Gyeongsang National University School of Medicine, Jinju (Korea, Republic of); Ryoo, Jae Wook [Dept. of Radiology, Samsung Seoul Hospital, Seoul (Korea, Republic of)

    2011-10-15

    To evaluate the usefulness of multidetector-row CT angiography (MDCTA) for the diagnosis of cerebral vasospasm after aneurysmal subarachnoid hemorrhage (SAH) by comparison of digital subtraction angiography (DSA) and to compare the bone subtraction CT angiography (BS-CTA) and standard CT angiography (S-CTA). Thirty-three patients who were treated with intraarterial nimodipine infusion for the cerebral vasospasm after aneurysmal SAH were evaluated with MDCTA and DSA. BS-CTA images were reconstructed from the S-CTA and unenhanced CT source images. A total of 207 vascular segments were evaluated. A four-step scale for the degree of stenosis was applied for each segment. With DSA as the standard images, BS-CTA and S-CTA images were comparied. On DSA, 56 segments (27%) presented vasospasm. Concordance between the DSA and S-CTA and between DSA and BS-CTA were 94.7% and 82.1%, respectively. Overestimation for the degree of stenosis was shown in 37 segments on BS-CTA and in 8 segments on S-CTA, but underestimated segments were only shown on S-CTA (n = 4). MDCTA with standard technique seems to be a useful imaging tool for the evaluation of the cerebral vasospasm after aneurysmal SAH. However, BS-CTA is not needed because of additional radiation and overestimation of the degree of stenosis.

  19. Bone Subtraction 3-Dimension CT Angiography Using 64-Slice Multidetector CT for the Evaluation of Steno-Occlusive Intra- and Extracranial Vascular Diseases: Comparison with Digital Subtraction Angiography

    Energy Technology Data Exchange (ETDEWEB)

    Park, Sung Eun; Choi, Dae Seob; Shin, Hwa Seon; You, Jin Jong; Park, Mi Jung; Cho, Jae Min; Choi, Ho Cheol; Son, Seung Nam [Gyeongsang National University School of Medicine, Jinju (Korea, Republic of); Ryu, Jae Wook [Dept. of Radiology, Samsung Seoul Hospital, Seoul (Korea, Republic of)

    2012-09-15

    To investigate the efficacy of bone subtraction CT angiography (BSCTA) for the evaluation of steno-occlusive intra- and extracranial vascular diseases. Fifty-six patients were examined using 64-slice multidetector CT and digital subtraction angiography (DSA). For BSCTA, both nonenhanced CT and enhanced CT angiography (CTA) data sets were obtained. The stenotic degree of each vascular segment was assessed and classified into 5 grades. With DSA as the standard, CTA images were compared. For the evaluation of the extracranial vessels, 370 arterial segments were analyzed, and the stenotic degree revealed by CTA and DSA agreed in 359 (97.0%). There was a significant correlation between CTA and DSA (Rs = 0.974). For depiction of {>=} 50% stenosis, the sensitivity, specificity, and diagnostic accuracy of BSCTA were 100%, 98.2%, and 98.6%, respectively. For the intracranial arteries, 1029 segments were analyzed, and CTA agreed with DSA in 966 (93.9%). There was a significant correlation between CTA and DSA for stenotic degree (Rs = 0.880). For the depiction of {>=} 50% stenosis, the sensitivity, specificity, and diagnostic accuracy of CTA were 100%, 95.8%, and 96.0%, respectively. In all 74 segments of disagreement, the degree of stenosis was overestimated on CTA. BSCTA is comparable to DSA for the evaluation of steno-occlusive intra- and extracranial vascular diseases. However, the stenotic degree tends to be overestimated on BSCTA, especially in cases of wall calcifications.

  20. Monte Carlo simulations in multi-detector CT (MDCT) for two PET/CT scanner models using MASH and FASH adult phantoms

    Science.gov (United States)

    Belinato, W.; Santos, W. S.; Paschoal, C. M. M.; Souza, D. N.

    2015-06-01

    The combination of positron emission tomography (PET) and computed tomography (CT) has been extensively used in oncology for diagnosis and staging of tumors, radiotherapy planning and follow-up of patients with cancer, as well as in cardiology and neurology. This study determines by the Monte Carlo method the internal organ dose deposition for computational phantoms created by multidetector CT (MDCT) beams of two PET/CT devices operating with different parameters. The different MDCT beam parameters were largely related to the total filtration that provides a beam energetic change inside the gantry. This parameter was determined experimentally with the Accu-Gold Radcal measurement system. The experimental values of the total filtration were included in the simulations of two MCNPX code scenarios. The absorbed organ doses obtained in MASH and FASH phantoms indicate that bowtie filter geometry and the energy of the X-ray beam have significant influence on the results, although this influence can be compensated by adjusting other variables such as the tube current-time product (mAs) and pitch during PET/CT procedures.

  1. Left and right ventricle assessment with Cardiac CT: validation study vs. Cardiac MR

    Energy Technology Data Exchange (ETDEWEB)

    Maffei, Erica; Seitun, Sara [Giovanni XXIII Hospital, Cardiovascular Radiology Unit, Monastier di Treviso (Italy); Messalli, Giancarlo; Catalano, Onofrio [SDN Foundation - IRCCS, Naples (Italy); Martini, Chiara; Cademartiri, Filippo [Giovanni XXIII Hospital, Cardiovascular Radiology Unit, Monastier di Treviso (Italy); Erasmus Medical Center, Department of Radiology and Cardiology, Rotterdam (Netherlands); Nieman, Koen; Rossi, Alexia; Mollet, Nico R. [Erasmus Medical Center, Department of Radiology and Cardiology, Rotterdam (Netherlands); Guaricci, Andrea I. [Azienda Ospedaliero-Universitaria di Foggia, Department of Cardiology, Foggia (Italy); Tedeschi, Carlo [Ospedale San Gennaro, Department of Cardiology, Naples (Italy)

    2012-05-15

    To compare Magnetic Resonance (MR) and Computed Tomography (CT) for the assessment of left (LV) and right (RV) ventricular functional parameters. Seventy nine patients underwent both Cardiac CT and Cardiac MR. Images were acquired using short axis (SAX) reconstructions for CT and 2D cine b-SSFP (balanced-steady state free precession) SAX sequence for MR, and evaluated using dedicated software. CT and MR images showed good agreement: LV EF (Ejection Fraction) (52 {+-} 14% for CT vs. 52 {+-} 14% for MR; r = 0.73; p > 0.05); RV EF (47 {+-} 12% for CT vs. 47 {+-} 12% for MR; r = 0.74; p > 0.05); LV EDV (End Diastolic Volume) (74 {+-} 21 ml/m{sup 2} for CT vs. 76 {+-} 25 ml/m{sup 2} for MR; r = 0.59; p > 0.05); RV EDV (84 {+-} 25 ml/m{sup 2} for CT vs. 80 {+-} 23 ml/m{sup 2} for MR; r = 0.58; p > 0.05); LV ESV (End Systolic Volume)(37 {+-} 19 ml/m{sup 2} for CT vs. 38 {+-} 23 ml/m{sup 2} for MR; r = 0.76; p > 0.05); RV ESV (46 {+-} 21 ml/m{sup 2} for CT vs. 43 {+-} 18 ml/m{sup 2} for MR; r = 0.70; p > 0.05). Intra- and inter-observer variability were good, and the performance of CT was maintained for different EF subgroups. Cardiac CT provides accurate and reproducible LV and RV volume parameters compared with MR, and can be considered as a reliable alternative for patients who are not suitable to undergo MR. circle Cardiac-CT is able to provide Left and Right Ventricular function. circle Cardiac-CT is accurate as MR for LV and RV volume assessment. (orig.)

  2. Three-dimensional CT angiographic assessment of pelvic and lower-extremity occlusive disease using single detector-row and multidetector-row CT scanners

    International Nuclear Information System (INIS)

    Three-dimensional CT angiography (3D-CTA) using a single detector-row CT (SDCT) scanner has become an important technique in the evaluation of the vascular system. A multidetector-row CT (MDCT) scanner, that is, a more advanced CT scanner which can acquire up to four channels of data simultaneously, has been recently introduced. With the use of this robust CT scanner, it is expected that more efficient 3D-CTAs will be obtained thanks to the superior temporal and spatial resolution provided by this technology. The purpose of this study was to assess the usefulness of 3D-CTA reconstructed from the data sets obtained using both SDCT and MDCT scanners, and to evaluate new software which was originally developed for the assessment of vascular wall pathology and vessel tortuosity. Twenty patients with pelvic arterial occlusive disease underwent 3D-CTA using a SDCT scanner. For stenoses and occlusions, 3D-CTA had a sensitivity of 93%, and a specificity of 89% as compared to digital subtraction angiography. Long anatomical range 3D-CT angiographic evaluations, from the pelvic artery to the lower legs, were performed in five patients with peripheral arterial occlusive disease using an MDCT scanner. All significant stenoses and occlusions were nicely depicted by the 3D-CTAs using the MDCT scanner. A new method for semiautomatically produced, curvedplanar reconstructed images along the vessel length based on a virtual CT endoscopic technique (CEV-CPR method) provided smoothly reformatted longitudinal images of the vessel. Using a new technique for assessing vessel tortuosity, we were able to quantitatively evaluate vessel tortuosity by calculating vessel curvature. In conclusion, 3D-CTA using SDCT and MDCT scanners and newly developed software provided useful qualitative and quantitative information concerning vascular pathology in patients with pelvic and lower-extremity occlusive disease. (author)

  3. Threshold adjusted calcium scoring using CT is less susceptible to cardiac motion and more accurate

    NARCIS (Netherlands)

    Groen, J. M.; Dijkstra, H.; Greuter, M. J. W.; Oudkerk, M.

    2009-01-01

    The purpose of this paper is to investigate calcium scoring on computed tomography (CT) using an adjusted threshold depending on the maximum Hounsfield value within the calcification (HU(peak)). The volume of 19 calcifications was retrospectively determined on 64-slice multidetector CT and dual sour

  4. Assessment of the anterior spinal artery and the artery of Adamkiewicz using multi-detector CT angiography

    Institute of Scientific and Technical Information of China (English)

    ZHAO Shao-hong; Laura Logan; Pamela Schraedley; Geoffrey D. Rubin

    2009-01-01

    Background Damage to the spinal cord after the treatment of the descending thoracic and thoracoabdominal aortic aneurysms is an uncommon but devastating complication. The artery of Adamkiewicz (AKA) is the principal arterial supply of the anterior spinal artery (ASA) in the lower thoracic and lumbar level. The purpose of this study was to evaluate the visualization of the anterior spinal artery and the artery of Adamkiewicz, the affecting factors for the detection rate using multi-detector row CT (MDCT). Methods Ninety-nine consecutive patients (31 women and 68 men; age range, 25-90 years; average age 61.3 years), with suspicion for thoracic aortic lesions necessitating surgical intervention (31 aortic aneurysm, 45 dissection, 5 intramural hematoma, and 18 normal), underwent CT angiography from the aortic arch to the aortic bifurcation. Transverse sections, multiplanar reformations and thin maximum intensity projections were used to assess the ASA and AKA. The level of the ASA and AKA origins and CT acquisition parameters were recorded. The contrast-to-noise ratio of the image, an index of the mass of the T11 body (vertebral mass index), the subcutaneous fat thickness, and the CT value within the aortic arch and at the T11 level were measured. The detection of the ASA and AKA were evaluated relative to the acquisition parameters, scan characteristics, and aortic lesion type. Differences were assessed with the Wilcoxon rank-sum and t tests. Results The ASA was visualized in 51 patients (52%) and the AKA in 18 patients (18%). The ASA was identified in 36/67 patients (54%) with 1.25 mm thickness and in 15/32 patients (47%) with 2.5-3.0 mm thickness. This difference did not achieve significance (P=0.13). The detection rate of the ASA and the AKA was influenced by the vertebral mass index and the contrast-to-noise ratio (P<0.05). The amount of subcutaneous fat affected the detection rate of the ASA (P <0.05) but not the AKA. In CT scans of ASA detection, the mean CT

  5. The diagnostic accuracy of multidetector row CT for evaluating the axillary lymph nodes in patients with breast cancer

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Doo Kyung; Kim, Jun Man; Yim, Hyun Ee [Ajou University, College of Medicine, Suwon (Korea, Republic of)

    2007-08-15

    We investigated the CT (computed tomography) findings of metastatic lymph nodes (LNs), and we analyzed the diagnostic performance of multidetector row CT (MDCT) for detecting axillary LN metastases in patients with breast cancer. We investigated 59 patients who preoperatively underwent chest MDCT, and they underwent sentinel LN biopsy ro whole axillary LN dissection. We analyzed the morphologic features, the degree of enhancement and the delayed enhancement pattern. We classified the patients into the non-metastatic LN group and the metastatic LN group, and we calculated the diagnostic performance of MDCT for detecting metastatic LNs. When both the morphologic and quantitative criteria were consistent, the sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) were 58.1%, 100%, 100% and 68.3%, respectively, and MDCT accurately detected metastatic LNs in 2 patients that were false negative on sentinel LN biopsy. When the morphologic and quantitative criteria were consistent, the sensitivity, specificity, PPV and NPV were 87.1%, 53.6%, 67.5% and 78.9%, respectively. However, MDCT could not detect metastatic LNs, including two micrometastases (a total of 8 micrometastases) that were in each of four patients. MDCT can be used to perform the morphology and quantitative analysis of axillary LNs, and this modality has excellent specificity and a PPV for detecting metastatic LNs when the both of the diagnostic criteria are consistent.

  6. Accuracy of hydro-multidetector row CT in the local T staging of oesophageal cancer compared to postoperative histopathological results

    International Nuclear Information System (INIS)

    To evaluate the accuracy of multidetector computed tomography with water filling (Hydro-MDCT) in the T-staging of patients with oesophageal cancer. There were 131 consecutive patients who were preoperatively and prospectively examined in the prone position on arterial phase contrast-enhanced MDCT, after ingestion of 1,000-1,500 ml tap water and effervescent granules. Two readers staged the local tumour growth (T-staging) independently. They assessed tumour location, size, presence of stenosis, and morphology of the outer border of the oesophageal wall and perioesophageal fat planes on CT. CT findings were compared with histopathological results from resected specimens. Data were analyzed using the SPSS statistical package. Both readers obtained a high sensitivity of 95% and a high positive predictive value of 96%. Accurate local staging was achieved in 76.3% and 68.7% for readers 1 and 2, respectively. Inter-reader agreement was excellent (weighted κ value of 0.93 and un-weighted κ of 0.89). Using the hydro-technique and applying specific assessment criteria, MDCT appears to be an accurate, non-invasive diagnostic tool for local tumour staging of oesophageal cancer. (orig.)

  7. Multidetector CT imaging of mechanical prosthetic heart valves: quantification of artifacts with a pulsatile in-vitro model

    Energy Technology Data Exchange (ETDEWEB)

    Symersky, Petr [Onze Lieve Vrouwe Gasthuis, Department of Cardiothoracic Surgery, Oosterpark 9, P.O box 95500, Amsterdam (Netherlands); Academic Medical Center, Department of Cardiothoracic Surgery, Amsterdam (Netherlands); Budde, Ricardo P.J. [University Medical Center, Department of Radiology, Utrecht (Netherlands); Westers, Paul [Julius Center for Health Sciences and Primary Care, Department of Biostatistics, Utrecht (Netherlands); Mol, Bas A.J.M. de [Academic Medical Center, Department of Cardiothoracic Surgery, Amsterdam (Netherlands); University of Technology Eindhoven, Department of Biomedical Engineering, Eindhoven (Netherlands); Prokop, Mathias [Radboud University Nijmegen Medical Center, Department of Radiology, Nijmegen (Netherlands)

    2011-10-15

    Multidetector computed tomography (MDCT) can detect the cause of prosthetic heart valve (PHV) dysfunction but is hampered by valve-induced artifacts. We quantified artifacts of four PHV using a pulsatile in-vitro model and assessed the relation to leaflet motion and valve design. A Medtronic Hall tilting disc (MH), and Carbomedics (CM), St Jude (SJM), and ON-X bileaflet valves underwent CT in an in-vitro model using retrospective gating with a 64 detector CT system in stationary and pulsatile conditions. Artifacts and radiopaque component volumes were quantified with thresholds based on surrounding structures and valvular components. Hypodense artifacts volumes (mm{sup 3}) were 1,029 {+-} 147, 535 {+-} 53, 371 {+-} 16, and 366 {+-} 18 for the SJM, MH, CM and ON-X valves (p < 0.001 except for the latter two valves p = 0.43). Hyperdense artifact volumes were 3,546 {+-} 141, 2,387 {+-} 103, 2,003 {+-} 102, and 3,033 {+-} 31 for the SJM, MH, CM and ON-X valve, respectively (all differences p < 0.001). Leaflet motion affected hypodense (F = 41.5, p < 0.001) and hyperdense artifacts (F = 53.7, p < 0.001). Closed and moving leaflets were associated with the least and the most artifacts respectively (p < 0.001, both artifact types). Both valve design and leaflet motion affect PHV-induced artifacts. Best imaging results may be expected for the CM valve during phases in which the leaflets are closed. (orig.)

  8. Differentiation of early gastric cancer with ulceration and resectable advanced gastric cancer using multiphasic dynamic multidetector CT

    International Nuclear Information System (INIS)

    Early gastric cancer with ulceration (EGC-U) mimics advanced gastric cancer (AGC), as EGC-Us and ACGs often have similar endoscopic appearance to ulceration. The purpose of this retrospective study was to determine whether multiphasic dynamic multidetector CT (MDCT) can help differentiate EGC-Us from AGCs. Patients with EGC-Us with ulcer stages Ul-III or IV and AGCs with tumour stages T2 to T4a were enrolled. MDCT images were obtained 40 s (arterial phase), 70 s (portal phase) and 240 s (delayed phase) after injection of non-ionic contrast material. Two readers independently measured the attenuation values of the lesions by placing regions of interest. We compared the EGC-Us and AGCs using the mean attenuation values in each phase and peak enhancement phase. We analysed the diagnostic performance of CT for differentiating EGC-Us from AGCs. Forty cases (16 EGC-Us and 24 AGCs) were analysed. The mean attenuation values of the EGC-Us were significantly lower than those of the AGCs in both the arterial and portal phases (all p < 0.0001 for each reader). The peak enhancement was significantly different between the EGC-Us and AGCs for both readers (Reader 1, p = 0.0131; Reader 2, p = 0.0006). Multiphasic dynamic contrast-enhanced MDCT can help differentiate EGC-Us from AGCs. (orig.)

  9. Differentiation of early gastric cancer with ulceration and resectable advanced gastric cancer using multiphasic dynamic multidetector CT

    Energy Technology Data Exchange (ETDEWEB)

    Tsurumaru, Daisuke; Miyasaka, Mitsutoshi; Nishimuta, Yusuke; Asayama, Yoshiki; Nishie, Akihiro; Honda, Hiroshi [Kyushu University, Department of Clinical Radiology, Graduate School of Medical Sciences, Fukuoka (Japan); Kawanami, Satoshi [Kyushu University, Department of Molecular Imaging and Diagnosis, Graduate School of Medical Sciences, Fukuoka (Japan); Oki, Eiji [Kyushu University, Department of Surgery and Sciences, Graduate School of Medical Sciences, Fukuoka (Japan); Hirahashi, Minako [Kyushu University, Department of Anatomic Pathology and Pathological Sciences, Graduate School of Medical Sciences, Fukuoka (Japan)

    2016-05-15

    Early gastric cancer with ulceration (EGC-U) mimics advanced gastric cancer (AGC), as EGC-Us and ACGs often have similar endoscopic appearance to ulceration. The purpose of this retrospective study was to determine whether multiphasic dynamic multidetector CT (MDCT) can help differentiate EGC-Us from AGCs. Patients with EGC-Us with ulcer stages Ul-III or IV and AGCs with tumour stages T2 to T4a were enrolled. MDCT images were obtained 40 s (arterial phase), 70 s (portal phase) and 240 s (delayed phase) after injection of non-ionic contrast material. Two readers independently measured the attenuation values of the lesions by placing regions of interest. We compared the EGC-Us and AGCs using the mean attenuation values in each phase and peak enhancement phase. We analysed the diagnostic performance of CT for differentiating EGC-Us from AGCs. Forty cases (16 EGC-Us and 24 AGCs) were analysed. The mean attenuation values of the EGC-Us were significantly lower than those of the AGCs in both the arterial and portal phases (all p < 0.0001 for each reader). The peak enhancement was significantly different between the EGC-Us and AGCs for both readers (Reader 1, p = 0.0131; Reader 2, p = 0.0006). Multiphasic dynamic contrast-enhanced MDCT can help differentiate EGC-Us from AGCs. (orig.)

  10. Detection of the anatomic structure and pathology in animal lung specimens: comparison of micro CT and multi-detector row CT

    International Nuclear Information System (INIS)

    We wanted to compare the capability of micro CT and the clinically available thin-slice multi-detector row CT (MDCT) for demonstrating fine anatomic structures and pathological lesions in formalin-fixed lung specimens. The porcine lung with shark liver oil-induced lipoid pneumonia and the canine lung with pulmonary paragonimiasis were fixed by ventilating them with formalin vapor, and they were then sliced into one-centimeter thick sections. Micro CT (section thickness, 18 micrometer) and MDCT (section thickness, 0.75 mm) images were acquired in four of the lung slices of the lipoid pneumonia specimen and in five of the lung slices of the paragonimiasis specimen. On 62 pairs of micro CT and MDCT images, 169 pairs of rectangular ROIs were manually drawn in the corresponding locations. Two chest radiologists recorded the detectability of three kinds of anatomic structures (lobular core structure, interlobular septum and small bronchiolar lumen) and two kinds of pathological lesions (ground-glass opacity and consolidation) with using a five-point scale. The statistical comparison was performed by using the Wilcoxon signed rank test. Interobserver agreement was evaluated with kappa statistics. For all observers, all the kinds of anatomic structures and pathological lesions were detected better on the micro CT images than on the MDCT images (ρ < 0.01). Agreement was fair between two observers (κ = 0.38, ρ < 0.001). The fine anatomic structures and pathological lesions of the lung were more accurately demonstrated on micro CT than on thin-slice MDCT in the inflated and fixed lung specimens

  11. Detection of the anatomic structure and pathology in animal lung specimens: comparison of micro CT and multi-detector row CT

    Energy Technology Data Exchange (ETDEWEB)

    Lim, Kun Young [National Cancer Center, Goyang (Korea, Republic of); Lee, Hyun Ju; Lee, Chang Hyun; Son, Kyu Ri; Goo, Jin Mo; Im, Jung Gi [Seoul National University Hospital and the Institute of Radiation Medicine, Seoul (Korea, Republic of); Seo, Joon Beom [Asan Medical Center, University of Ulsan College of Medicine, Seoul (Korea, Republic of)

    2006-05-15

    We wanted to compare the capability of micro CT and the clinically available thin-slice multi-detector row CT (MDCT) for demonstrating fine anatomic structures and pathological lesions in formalin-fixed lung specimens. The porcine lung with shark liver oil-induced lipoid pneumonia and the canine lung with pulmonary paragonimiasis were fixed by ventilating them with formalin vapor, and they were then sliced into one-centimeter thick sections. Micro CT (section thickness, 18 micrometer) and MDCT (section thickness, 0.75 mm) images were acquired in four of the lung slices of the lipoid pneumonia specimen and in five of the lung slices of the paragonimiasis specimen. On 62 pairs of micro CT and MDCT images, 169 pairs of rectangular ROIs were manually drawn in the corresponding locations. Two chest radiologists recorded the detectability of three kinds of anatomic structures (lobular core structure, interlobular septum and small bronchiolar lumen) and two kinds of pathological lesions (ground-glass opacity and consolidation) with using a five-point scale. The statistical comparison was performed by using the Wilcoxon signed rank test. Interobserver agreement was evaluated with kappa statistics. For all observers, all the kinds of anatomic structures and pathological lesions were detected better on the micro CT images than on the MDCT images ({rho} < 0.01). Agreement was fair between two observers ({kappa} = 0.38, {rho} < 0.001). The fine anatomic structures and pathological lesions of the lung were more accurately demonstrated on micro CT than on thin-slice MDCT in the inflated and fixed lung specimens.

  12. Haemodynamic findings on cardiac CT in children with congenital heart disease

    Energy Technology Data Exchange (ETDEWEB)

    Goo, Hyun Woo [University of Ulsan College of Medicine, Department of Radiology and Research Institute of Radiology, Asan Medical Center, Seoul (Korea, Republic of)

    2011-02-15

    In patients with congenital heart disease, haemodynamic findings demonstrated on cardiac CT might provide useful hints for understanding the haemodynamics of cardiac defects. In contrast to morphological features depicted on cardiac CT, such haemodynamic findings on cardiac CT have not been comprehensively reviewed in patients with congenital heart disease. This article describes normal haemodynamic phenomena of cardiovascular structures and various abnormal haemodynamic findings with their mechanisms and clinical significance on cardiac CT in patients with congenital heart disease. (orig.)

  13. Temporal evolution of multidetector CT findings after endoscopic submucosal dissection in patients with early gastric cancer: Correlation with endoscopy

    Energy Technology Data Exchange (ETDEWEB)

    Yeo, Dong Myung, E-mail: duehdaud@gmail.com [Department of Radiology, Yeouido St. Mary' s Hospital, The Catholic University of Korea (Korea, Republic of); Chung, Dong Jin, E-mail: bookdoo7@catholic.ac.kr [Department of Radiology, Yeouido St. Mary' s Hospital, The Catholic University of Korea (Korea, Republic of); Cheung, Dae Young, E-mail: adagio@catholic.ac.kr [Department of Internal Medicine, Yeouido St. Mary' s Hospital, The Catholic University of Korea (Korea, Republic of); Lee, Jae Mun, E-mail: jaemun@catholic.ac.kr [Department of Radiology, Yeouido St. Mary' s Hospital, The Catholic University of Korea (Korea, Republic of)

    2014-06-15

    Objective: To assess changes over time in imaging findings retrospectively by multidetector CT (MDCT) with two-dimensional (2D) multiplanar reconstruction and three-dimensional (3D) CT gastrography (CTG), after endoscopic submucosal dissection (ESD) in patients with early gastric cancer (EGC), and to correlate 3D CT images with endoscopic appearance. Materials and methods: In this retrospective study, a total of 84 patients underwent ESD and were followed up with MDCT. Fifteen patients underwent CT twice, and 3 patients underwent CT 3 times. A total of 105 CTs were included in this study and 43 CTs contained 3D CTGs. Two radiologists in consensus interpreted CT images for lesion detectability, presence and characteristics of ulcer, focal wall thickening, perigastric fat infiltration, and overlying enhancing layer in 2D images. The presence of ulcer or subtle mucosal nodularity, ulcer mound, and fold convergence were analysed in 3D CT images. We also assessed the time interval between ESD and CT and analysed the temporal evolution of CT findings. The sensitivity, specificity, and overall accuracy of 3D CTG were assessed regarding endoscopic features as the gold standard. Results: The mean interval between ESD and follow up CT was 76.9 days (median, 62; range, 2–223). No tumour recurrence in any lesion was found on follow-up endoscopic biopsy and also lymph node or distant metastasis was not observed on CT exams in the follow-up period. The lesion detectability in a total of 105 post-ESD 2D CT images was 42.0% (44/105), and 93.2% (41/44) of the detected lesions were visualizable 2 months after ESD. Focal wall thickening was observed during the entire follow-up period in all patients. Perigastric fat infiltration was observed in 4 lesions within 1 week of ESD. Overlying enhancing layer appeared in 27 lesions without temporal evolution. On a total of 43 post-ESD 3D CTG, lesion detectability was 76.7% (33/43), and lesions could be visualized for a longer period than

  14. Evaluation of visibility of lumen of coronary stents by CT coronary angiography using multi-detector row CT in our hospital

    International Nuclear Information System (INIS)

    Many experiments of evaluation of coronary stents by CT coronary angiography (CTCA) using multi-detector row computed tomography (MDCT) are reported since the appearance of 16-row and 64-row CT. However, blooming artifact makes the assessment of lumen of coronary stent (LCS) difficult at present. The purpose of this study is to investigate the evaluation of visibility of LCS by CTCA. CTCA was performed in 25 patients who had previously undergone stent implantation scanned using 64-row CT, and images of 32 stents were obtained. All images were classified into 4 grades (4: excellent, 3: good, 2: fair, 1: poor) according to their visibility of LCS. We investigated the correlation of stent characteristics and backgrounds (diameter, material and thickness of strut, the period from stent implantation to CTCA, the location of stent, and whether calcification or not) with the grade of visibility. We found the conditions of good visibility of LCS were the diameter >3.5 mm (ratio of ≥grade 3 was 77.8%=14/18 stents), thin strut (<100 μm), and no calcification (ratio of ≥grade 3 was 87.5%=14/16 stents). We expected that CTCA using MDCT will be established useful examination of evaluation of LCS in future. (author)

  15. Cine CT for Attenuation Correction in Cardiac PET/CT

    OpenAIRE

    Alessio, Adam M.; Kohlmyer, Steve; Branch, Kelley; Chen, Grace; Caldwell, James; Kinahan, Paul

    2007-01-01

    In dual-modality PET/CT systems, the CT scan provides the attenuation map for PET attenuation correction. The current clinical practice of obtaining a single helical CT scan provides only a snapshot of the respiratory cycle, whereas PET occurs over multiple respiratory cycles. Misalignment of the attenuation map and emission image because of respiratory motion causes errors in the attenuation correction factors and artifacts in the attenuation-corrected PET image. To rectify this problem, we ...

  16. The relationship between coronary artery calcification detected by non-gated multi-detector CT in patients with suspected ischemic heart disease and myocardial ischemia detected by thallium exercise stress testing

    International Nuclear Information System (INIS)

    The objective of this study was to examine whether we could predict myocardial ischemia when coronary artery calcification is detected by non-gated multidetector CT in patients with suspected ischemic heart disease. Eighty-three patients suspected of having ischemic heart disease (55 men, 28 women; age range 36-83 years; mean age 68 years) underwent multidetector CT and Tl-201 single photon emission computed tomography. Prediction of myocardial ischemia by coronary arterial calcification detected on CT was evaluated by comparing the coronary artery territories that showed calcification with the area of myocardial ischemia determined by SPECT. The sensitivity, specificity, positive predictive value, and negative predictive value of multidetector CT for predicting myocardial ischemia were calculated. Coronary angiography was also examined and compared with multidetector CT. Risk factors, including hypertension, smoking, hyperlipidemia, diabetes, and family history, were compared for evidence of coronary artery calcification detected by multidetector CT and myocardial ischemia detected by thallium nuclear scans. For analysis by patients, the sensitivity, specificity, positive predictive value, and negative predictive value of coronary artery calcification for myocardial ischemia detection were 65, 63, 56, and 71%, respectively. Similarly, for analysis by coronary arterial territories, those values were 56, 77, 41 and 86%, respectively. Coronary stenosis on CAG was also related to the ischemia determined by SPECT and calcification on multidetector CT. Ischemia was better influenced by risk factors than was coronary arterial calcification. For analysis by coronary arterial territories, the specificity and negative predictive value of coronary arterial calcification seen by multidetector CT are relatively high. (author)

  17. Comparison of two-dimensional CT with virtual gastrography using multi-detector CT in the diagnosis of early gastric cancer

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jee Eun; Eun, Hyo Won [Ewha Womans University Dongdaemoon Hospital, Seoul (Korea, Republic of); Kim, Jung Hoon [Soon Chun Hyan University Hospital, Seoul (Korea, Republic of)

    2006-12-15

    We compared the performance of virtual gastrography (VG) using multi-detector (MDCT) with two-dimensional (2D) in the diagnosis of early gastric cancer (EGC). We performed conventional gastroscopy and MDCT examination after gaseous distension of the stomach in 50 consecutive patients who were confirmed as EGC by surgery and endoscopic mucosal resection. Unenhanced images were obtained in the prone position and contrast enhanced images were obtained in the supine position. Contrast enhanced imaging was done 70 seconds after intravenous injection of 150 mL of ionic contrast material at the rate of 3 mL/sec. 2D CT and VG images were analyzed by two radiologist with consensus to assess the location and gross morphologic type of EGC. Crosstabs were used to determine the diagnostic accuracy of EGC on 2D CT and VG. The diagnostic specificity for 50 patients with EGC was significantly higher with VG (72%) than with 2D CT (88%) ({rho} < ). VG depicted EGC in eight patients (type I = 1; type IIa = 3; type IIb 1; type IIc = 2; type IIa + IIc = 1) that were missed on the 2D CT. The lesions were located in the antrum (n = 6), angle (n = 1), and body (n = 1). However, VG frequently misdiagnosed EGCs of type IIb (n = 4), IIc (n = 1), and III (n = 1), as well as the location at the angle (n = 3), antrum (n 1), and body (n = 1). VG showed excellent result in the detection of EGC compared with 2D CT. However, it had limitations in the diagnosis of EGC type IIb or gastric angle tumor.

  18. Quantitative image quality evaluation for cardiac CT reconstructions

    Science.gov (United States)

    Tseng, Hsin-Wu; Fan, Jiahua; Kupinski, Matthew A.; Balhorn, William; Okerlund, Darin R.

    2016-03-01

    Maintaining image quality in the presence of motion is always desirable and challenging in clinical Cardiac CT imaging. Different image-reconstruction algorithms are available on current commercial CT systems that attempt to achieve this goal. It is widely accepted that image-quality assessment should be task-based and involve specific tasks, observers, and associated figures of merits. In this work, we developed an observer model that performed the task of estimating the percentage of plaque in a vessel from CT images. We compared task performance of Cardiac CT image data reconstructed using a conventional FBP reconstruction algorithm and the SnapShot Freeze (SSF) algorithm, each at default and optimal reconstruction cardiac phases. The purpose of this work is to design an approach for quantitative image-quality evaluation of temporal resolution for Cardiac CT systems. To simulate heart motion, a moving coronary type phantom synchronized with an ECG signal was used. Three different percentage plaques embedded in a 3 mm vessel phantom were imaged multiple times under motion free, 60 bpm, and 80 bpm heart rates. Static (motion free) images of this phantom were taken as reference images for image template generation. Independent ROIs from the 60 bpm and 80 bpm images were generated by vessel tracking. The observer performed estimation tasks using these ROIs. Ensemble mean square error (EMSE) was used as the figure of merit. Results suggest that the quality of SSF images is superior to the quality of FBP images in higher heart-rate scans.

  19. Comparison of neutral oral contrast versus positive oral contrast medium in abdominal multidetector CT

    Energy Technology Data Exchange (ETDEWEB)

    Berther, Ralph; Eckhardt, Boris; Zollikofer, Christoph L. [Kantonsspital, Institute of Radiology, Winterthur (Switzerland); Patak, Michael A. [Kantonsspital, Institute of Radiology, Winterthur (Switzerland); Inselspital, University Hospital of Bern, Institute of Diagnostic, Interventional and Paediatric Radiology, Bern (Switzerland); Erturk, Sukru M. [Sisli Etfal Education and Research Hospital, Department of Radiology, Istanbul (Turkey)

    2008-09-15

    To determine whether neutral contrast agents with water-equivalent intraluminal attenuation can improve delineation of the bowel wall and increase overall image quality for a non-selected patient population, a neutral oral contrast agent (3% mannitol) was administered to 100 patients referred for abdominal multidetector row computed tomography (MDCT). Their results were compared with those of 100 patients given a positive oral contrast agent. Qualitative and quantitative measurements were done on different levels of the gastrointestinal tract by three experienced readers. Patients given the neutral oral contrast agent showed significant better qualitative results for bowel distension (P<0.001), homogeneity of the luminal content (P<0.001), delineation of the bowel-wall to the lumen (P<0.001) and to the mesentery (P<0.001) and artifacts (P<0.001), leading to a significant better overall image quality (P<0.001) than patients receiving positive oral contrast medium. The quantitative measurements revealed significant better distension (P<0.001) and wall to lumen delineation (P<0.001) for the patients receiving neutral oral contrast medium. The present results show that the neutral oral contrast agent (mannitol) produced better distension, better homogeneity and better delineation of the bowel wall leading to a higher overall image quality than the positive oral contrast medium in a non-selected patient population. (orig.)

  20. Accuracy of multidetector-row CT in diagnosing lymph node metastasis in patients with gastric cancer

    International Nuclear Information System (INIS)

    The purpose of this study was to determine the optimal cut-off value of lymph node size for diagnosing metastasis in gastric cancer with multidetector-row computed tomography (MDCT) after categorizing perigastric lymph nodes into three regions. The study included 90 gastric cancer patients who underwent gastrectomy. The long-axis diameter (LAD) and short-axis diameter (SAD) of all visualized lymph nodes were measured with transverse MDCT images. The locations of lymph nodes were categorized into three regions: lesser curvature, greater curvature, and suprapancreatic. The diagnostic value of lymph node metastasis was assessed with receiver operating characteristic (ROC) analysis. The area under the curve was larger for SAD than LAD in all groups. The optimal cut-off values of SAD were determined as follows: overall, 9 mm; differentiated type, 9 mm; undifferentiated type, 8 mm; lesser curvature region, 7 mm; greater curvature region, 6 mm; and suprapancreatic region, 9 mm. The diagnostic accuracies for lymph node metastasis using individual cut-off values were 71.1 % based on histological type and 76.6 % based on region of lymph node location. The diagnostic accuracy of lymph node metastasis in gastric cancer was improved by using individual cut-off values for each lymph node region. (orig.)

  1. Accuracy of multidetector-row CT in diagnosing lymph node metastasis in patients with gastric cancer

    Energy Technology Data Exchange (ETDEWEB)

    Saito, Takuro; Kurokawa, Yukinori; Takiguchi, Shuji; Miyazaki, Yasuhiro; Takahashi, Tsuyoshi; Yamasaki, Makoto; Miyata, Hiroshi; Nakajima, Kiyokazu; Mori, Masaki; Doki, Yuichiro [Osaka University, Graduate School of Medicine, Department of Gastroenterological Surgery, Suita, Osaka (Japan)

    2014-08-06

    The purpose of this study was to determine the optimal cut-off value of lymph node size for diagnosing metastasis in gastric cancer with multidetector-row computed tomography (MDCT) after categorizing perigastric lymph nodes into three regions. The study included 90 gastric cancer patients who underwent gastrectomy. The long-axis diameter (LAD) and short-axis diameter (SAD) of all visualized lymph nodes were measured with transverse MDCT images. The locations of lymph nodes were categorized into three regions: lesser curvature, greater curvature, and suprapancreatic. The diagnostic value of lymph node metastasis was assessed with receiver operating characteristic (ROC) analysis. The area under the curve was larger for SAD than LAD in all groups. The optimal cut-off values of SAD were determined as follows: overall, 9 mm; differentiated type, 9 mm; undifferentiated type, 8 mm; lesser curvature region, 7 mm; greater curvature region, 6 mm; and suprapancreatic region, 9 mm. The diagnostic accuracies for lymph node metastasis using individual cut-off values were 71.1 % based on histological type and 76.6 % based on region of lymph node location. The diagnostic accuracy of lymph node metastasis in gastric cancer was improved by using individual cut-off values for each lymph node region. (orig.)

  2. A comparative review of multidetector CT angiography and MRI in the diagnosis of jugular foramen lesions

    Energy Technology Data Exchange (ETDEWEB)

    Christie, A., E-mail: andychristie90@hotmail.co [Radiology Department, Institute of Neurosciences, Glasgow, Scotland (United Kingdom); Teasdale, E. [Radiology Department, Institute of Neurosciences, Glasgow, Scotland (United Kingdom)

    2010-03-15

    Aim: To compare the efficiency of multidetector computed tomography (MDCT) and magnetic resonance imaging (MRI) in the diagnosis of jugular foramen lesions. Materials and methods: The imaging of 15 patients with tumours predominantly occurring at the jugular foramen was retrospectively reviewed, with postoperative pathology data available for 11 patients. MDCT was performed at arterial phase and MRI with standard sequences and contrast enhancement. All imaging was blindly re-reported by an experienced neuroradiologist. Results: Pathology reported six glomus jugulare tumours and five neuromas, which were all correctly diagnosed using MDCT. A confident diagnosis was also made in the remaining four cases based on the pattern of enhancement. Only glomus tumours enhanced in the arterial phase. Overall, MRI was used to make a confident diagnosis in eight patients. One showed no enhancement and was correctly diagnosed as a neuroma, and seven demonstrated the tumour flow voids characteristic of a glomus tumour. The remaining seven cases all showed a similar enhancement pattern and could not be confidently differentiated between a neuroma or a glomus tumour. MDCT angiography enabled a confident assessment of the jugular vein in all cases, but MRI was inconclusive in a third of cases. Also, in the nine cases of glomus tumour diagnosed using MDCT, an enlarged feeding artery was identified in eight patients. Conclusion: MDCT is more accurate than MRI in diagnosing glomus tumours, and in particular, neuromas. It also offers valuable preoperative vascular information to the surgeon.

  3. Contrast enhancement pattern on multidetector CT predicts malignancy in pancreatic endocrine tumours

    Energy Technology Data Exchange (ETDEWEB)

    Cappelli, Carla [University of Pisa, Diagnostic and Interventional Radiology, Department of Translational Research and New Technologies in Medicine and Surgery, Pisa (Italy); Azienda Ospedaliero-Universitaria Pisana-Radiodiagnostica I, Pisa (Italy); Boggi, Ugo [University of Pisa, General and Transplant Surgery, Department of Translational Research and New Technologies in Medicine and Surgery, Pisa (Italy); Mazzeo, Salvatore; Cervelli, Rosa; Contillo, Benedetta Pontillo; Bartolozzi, Carlo [University of Pisa, Diagnostic and Interventional Radiology, Department of Translational Research and New Technologies in Medicine and Surgery, Pisa (Italy); Campani, Daniela; Funel, Niccola [University of Pisa, Pathology, Department of Surgical, Medical, Molecular and Critical Area Pathology, Pisa (Italy)

    2014-12-02

    Preoperative suspicion of malignancy in pancreatic neuroendocrine tumours (pNETs) is mostly based on tumour size. We retrospectively reviewed the contrast enhancement pattern (CEP) of a series of pNETs on multiphasic multidetector computed tomography (MDCT), to identify further imaging features predictive of lesion aggressiveness. Sixty pNETs, diagnosed in 52 patients, were classified based on CEP as: type A showing early contrast enhancement and rapid wash-out; type B presenting even (B1) or only (B2) late enhancement. All tumours were resected allowing pathologic correlations. Nineteen pNETs showed type A CEP (5-20 mm), 29 type B1 CEP (5-80 mm) and 12 type B2 (15-100 mm). All tumours were classified as well differentiated tumours, 19 were benign (WDt-b), 15 with uncertain behaviour (WDt-u) and 26 carcinomas (WDC). None of A lesions were malignant (12 WDt-b; 7 WDt-u), all B2 lesions were WDC, 7 B1 lesions were WDt-b, 8 WDt-u and 14 WDC; 4/34 (12 %) lesions ≤2cm were WDC. CEP showed correlation with all histological prognostic indicators. Correlating with the lesion grading and other histological prognostic predictors, CEP may preoperatively suggest the behaviour of pNETs, assisting decisions about treatment. Moreover CEP allows recognition of malignant small tumours, incorrectly classified on the basis of their dimension. (orig.)

  4. CT findings of intraductal papillary neoplasm of the bile duct: Assessment with multiphase contrast-enhanced examination using multi-detector CT

    Energy Technology Data Exchange (ETDEWEB)

    Ogawa, H., E-mail: ogawa.hiroshi@h.mbox.nagoya-u.ac.jp [Department of Radiology, Nagoya University Graduate School of Medicine, Nagoya (Japan); Itoh, S. [Department of Radiology, Japanese Red Cross Nagoya Daiichi Hospital, Nagoya (Japan); Nagasaka, T. [Department of Medical Technology, Nagoya University School of Health Sciences, Nagoya (Japan); Suzuki, K. [Department of Radiology, Nagoya University Graduate School of Medicine, Nagoya (Japan); Ota, T. [Department of Radiology, Aichi Medical University Hospital, Nagakute Aichi (Japan); Naganawa, S. [Department of Radiology, Nagoya University Graduate School of Medicine, Nagoya (Japan)

    2012-03-15

    Aim: To evaluate multi-detector computed tomography (MDCT) findings of intraductal papillary neoplasm of the bile duct (IPNB), a neoplasm that is considered to be the biliary counterpart of pancreatic intraductal papillary mucinous neoplasm. Materials and methods: Two radiologists retrospectively evaluated multiphase contrast-enhanced CT images with 0.5 or 1 mm collimation in 37 consecutive patients with resected IPNB diagnosed by a single pathologist. The CT findings were correlated with the pathological findings concerning invasion of the surrounding organs and vessels. Results: All patients showed bile duct dilatation. An intraductal mass was detected in 36 patients and the following findings were observed: extensive infiltration along the bile duct more than 20 mm (n = 32), compared with normal hepatic parenchyma, isodense or hyperdense during the late arterial phase (n = 31), not hyperdense during the portal-venous and delayed phases (n = 36), and intense enhancement rim at the base of the mass during the portal-venous or delayed phase (n = 27). Parenchymal invasion of the surrounding organs was seen in eight of 16 tumours showing irregular or bulging margins. Vascular invasion was false positive in four of eight tumours. Conclusions: IPNB exhibits relatively characteristic findings with multiphase contrast-enhanced examination using MDCT. A tendency to overestimate invasion of the surrounding organs and vessels was seen.

  5. Preoperative multidetector CT manifestations of perigastric lymph nodes in patients with early gastric cancer and pN0

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Jung Hyun; Yu, Jeong Sik; Chung, Jae Joon; Lim, Joo Hee; Cho, Eun Suk; Kim, Ki Whang [Dept. of Radiology, Yonsei University College of Medicine, Gangnam Severance Hospital, Seoul (Korea, Republic of)

    2013-11-15

    To find the determinant of lymph node (LN) manifestations on preoperative multidetector CT (MDCT) in early gastric cancer (EGC) patients with pN0. One hundred and eighty-six consecutive patients with pT1pN0, the largest perigastric LN on preoperative MDCT, were categorized into two groups according to 8 different parameters [short (SD) and long diameter (LD) 4/6/8 mm, average attenuation 100 Hounsfield unit, short-to-long diameter-ratio (SLR) 0.7], and correlated with the size, gross type, depth of invasion and microscopic type of their primary lesions by the chi-square test and multiple logistic regression analysis. When the primary lesion was larger than 3 cm, the LNs were larger in 4 parameters (SD or LD, 4/6 mm; p < 0.05); gross type IIb patients showed smaller LNs in 5 parameters (SD 4/6 mm, LD 4/6/8 mm; p < 0.05); and patients with microscopically-undifferentiated lesions showed larger LNs in SD 4 mm or LD 8 mm by the chi-square test and multiple logistic regression analysis. The depth of invasion showed no significant difference in LN size. No factors revealed significant difference in LN attenuation or SLR. Benign regional LN enlargement is more frequent in EGC patients with larger size primary lesions or lesion with poor microscopic differentiation. However, this condition is less frequent in gross type IIb patients.

  6. Tracheal compression due to an elongated aortic arch in patients with congenital heart disease: evaluation using multidetector-row CT

    Energy Technology Data Exchange (ETDEWEB)

    Watanabe, Noriko; Hayabuchi, Yasunobu; Inoue, Miki; Sakata, Miho; Nabo, Manal Mohamed Helmy; Nakagawa, Ryuji; Saijo, Takahiko; Kagami, Shoji [University of Tokushima, Department of Pediatrics, Tokushima (Japan)

    2009-10-15

    The airway can become obstructed as a result of compression by an elongated aortic arch. In this study we evaluated tracheal compression using multidetector-row CT in patients with congenital heart disease and an elongated aortic arch. The trachea was measured at the level of the aortic arch in 205 children and young adults and then the severity of tracheal compression was determined by measuring the tracheal diameter ratio (short axis diameter/long axis diameter). Patients were divided as follows: group I (normal aortic arch; n=166), group II (transversely running aortic arch; n=22), and group III (elongated aortic arch; n=17). From the viewpoint of the relationship of the great arteries, group II had D-malposition, and group III had L-malposition. Age, height, weight and body surface area were significantly correlated with the short and long axis diameter in group I. There was a negative correlation between tracheal diameter ratio and the physical size parameters. The tracheal diameter ratio in group III was 0.50{+-}0.13, which was significantly lower than in groups I and II (P<0.01 and 0.05, respectively). Even apparently asymptomatic patients with an elongated aortic arch can have tracheal compression. An elongated aortic arch may be a useful predictor of tracheal compression. (orig.)

  7. Accuracy of hepatocellular carcinoma detection on multidetector CT in a transplant liver population with explant liver correlation

    International Nuclear Information System (INIS)

    Aim: To evaluate the diagnostic accuracy of multidetector computed tomography (MDCT) for hepatocellular carcinoma (HCC) in cirrhotic patients undergoing liver transplantation. Secondary aims were to examine the effect of radiologist experience and lesion size on diagnostic accuracy. Materials and methods: Thirty-nine patients (72% male with a mean age of 56.5 years) underwent liver transplantation following preoperative triple-phase MDCT examination of the liver. MDCT examinations were retrospectively independently reviewed by three radiologists for the presence and location of suspected HCCs, with the diagnostic confidence recorded using a five-point confidence scale. MDCT examinations were compared with explant specimens for histopathological correlation. Results: Histopathological results demonstrated 46 HCCs in 29 of the 39 patients. Analysis demonstrated a sensitivity of 65-75% and specificity of 47-88% for detection of HCC lesions. The sensitivity dropped to 48-57% for lesions of size ≤20 mm. As the diagnostic confidence increased, there was a further decrease in the sensitivity (4-26%). The radiologist with the greatest number of years experience was found to have a significantly higher accuracy of detection of HCC lesions compared with the least experienced radiologist. Conclusion: Larger lesion size of HCC and greater number of years experience of the radiologist resulted in significantly higher accuracy of HCC lesion detection. The overall sensitivity and specificity results for MDCT detection of HCC are comparable to previous helical CT imaging.

  8. Accuracy of hepatocellular carcinoma detection on multidetector CT in a transplant liver population with explant liver correlation

    Energy Technology Data Exchange (ETDEWEB)

    Addley, H.C., E-mail: helenclareaddley@hotmail.co.u [Department of Radiology, Addenbrooke' s Hospital, Cambridge University Hospitals NHS Foundation Trust, Cambridge (United Kingdom); Griffin, N.; Shaw, A.S.; Mannelli, L. [Department of Radiology, Addenbrooke' s Hospital, Cambridge University Hospitals NHS Foundation Trust, Cambridge (United Kingdom); Parker, R.A. [Department of Medical Statistics, Addenbrooke' s Hospital, Cambridge University Hospitals NHS Foundation Trust, Cambridge (United Kingdom); Aitken, S.; Wood, H. [Department of Radiology, Addenbrooke' s Hospital, Cambridge University Hospitals NHS Foundation Trust, Cambridge (United Kingdom); Davies, S. [Department of Histopathology, Addenbrooke' s Hospital, Cambridge University Hospitals NHS Foundation Trust, Cambridge (United Kingdom); Alexander, G.J. [Department of Hepatology, Addenbrooke' s Hospital, Cambridge University Hospitals NHS Foundation Trust, Cambridge (United Kingdom); Lomas, D.J. [Department of Radiology, Addenbrooke' s Hospital, Cambridge University Hospitals NHS Foundation Trust, Cambridge (United Kingdom)

    2011-04-15

    Aim: To evaluate the diagnostic accuracy of multidetector computed tomography (MDCT) for hepatocellular carcinoma (HCC) in cirrhotic patients undergoing liver transplantation. Secondary aims were to examine the effect of radiologist experience and lesion size on diagnostic accuracy. Materials and methods: Thirty-nine patients (72% male with a mean age of 56.5 years) underwent liver transplantation following preoperative triple-phase MDCT examination of the liver. MDCT examinations were retrospectively independently reviewed by three radiologists for the presence and location of suspected HCCs, with the diagnostic confidence recorded using a five-point confidence scale. MDCT examinations were compared with explant specimens for histopathological correlation. Results: Histopathological results demonstrated 46 HCCs in 29 of the 39 patients. Analysis demonstrated a sensitivity of 65-75% and specificity of 47-88% for detection of HCC lesions. The sensitivity dropped to 48-57% for lesions of size {<=}20 mm. As the diagnostic confidence increased, there was a further decrease in the sensitivity (4-26%). The radiologist with the greatest number of years experience was found to have a significantly higher accuracy of detection of HCC lesions compared with the least experienced radiologist. Conclusion: Larger lesion size of HCC and greater number of years experience of the radiologist resulted in significantly higher accuracy of HCC lesion detection. The overall sensitivity and specificity results for MDCT detection of HCC are comparable to previous helical CT imaging.

  9. Detection and localization of acute upper and lower gastrointestinal (GI) bleeding with arterial phase multi-detector row helical CT

    Energy Technology Data Exchange (ETDEWEB)

    Jaeckle, T.; Stuber, G.; Hoffmann, M.H.K.; Jeltsch, M.; Schmitz, B.L.; Aschoff, A.J. [University Hospital of Ulm, Diagnostic and Interventional Radiology, Ulm (Germany)

    2008-07-15

    The purpose of this study was to evaluate the accuracy of multi-detector row helical CT (MDCT) for detection and localization of acute upper and lower gastrointestinal (GI) hemorrhage or intraperitoneal bleeding. Thirty-six consecutive patients with clinical signs of acute bleeding underwent biphasic (16- or 40-channel) MDCT. MDCT findings were correlated with endoscopy, angiography or surgery. Among the 36 patients evaluated, 26 were examined for GI bleeding and 10 for intraperitoneal hemorrhage. Confirmed sites of GI bleeding were the stomach (n = 5), duodenum (n = 5), small bowel (n = 6), large bowel (n = 8) and rectum (n = 2). The correct site of bleeding was identifiable on MDCT in 24/26 patients with GI bleeding. In 20 of these 24 patients, active CM extravasation was apparent during the exam. Among the ten patients with intraperitoneal hemorrhage, MDCT correctly identified the bleeding source in nine patients. Our findings suggest that fast and accurate localization of acute gastrointestinal and intraperitoneal bleeding is achievable on MDCT. (orig.)

  10. Detection and localization of acute upper and lower gastrointestinal (GI) bleeding with arterial phase multi-detector row helical CT

    International Nuclear Information System (INIS)

    The purpose of this study was to evaluate the accuracy of multi-detector row helical CT (MDCT) for detection and localization of acute upper and lower gastrointestinal (GI) hemorrhage or intraperitoneal bleeding. Thirty-six consecutive patients with clinical signs of acute bleeding underwent biphasic (16- or 40-channel) MDCT. MDCT findings were correlated with endoscopy, angiography or surgery. Among the 36 patients evaluated, 26 were examined for GI bleeding and 10 for intraperitoneal hemorrhage. Confirmed sites of GI bleeding were the stomach (n = 5), duodenum (n = 5), small bowel (n = 6), large bowel (n = 8) and rectum (n = 2). The correct site of bleeding was identifiable on MDCT in 24/26 patients with GI bleeding. In 20 of these 24 patients, active CM extravasation was apparent during the exam. Among the ten patients with intraperitoneal hemorrhage, MDCT correctly identified the bleeding source in nine patients. Our findings suggest that fast and accurate localization of acute gastrointestinal and intraperitoneal bleeding is achievable on MDCT. (orig.)

  11. Multidetector CT radiation dose optimisation in adults: short- and long-term effects of a clinical audit

    International Nuclear Information System (INIS)

    To report short- and long-term effects of an audit process intended to optimise the radiation dose from multidetector row computed tomography (MDCT). A survey of radiation dose from all eight MDCT departments in the state of Luxembourg performed in 2007 served as baseline, and involved the most frequently imaged regions (head, sinus, cervical spine, thorax, abdomen, and lumbar spine). CT dose index volume (CTDIvol), dose-length product per acquisition (DLP/acq), and DLP per examination (DLP/exa) were recorded, and their mean, median, 25th and 75th percentiles compared. In 2008, an audit conducted in each department helped to optimise doses. In 2009 and 2010, two further surveys evaluated the audit's impact on the dose delivered. Between 2007 and 2009, DLP/exa significantly decreased by 32-69 % for all regions (P < 0.001) except the lumbar spine (5 %, P = 0.455). Between 2009 and 2010, DLP/exa significantly decreased by 13-18 % for sinus, cervical and lumbar spine (P ranging from 0.016 to less than 0.001). Between 2007 and 2010, DLP/exa significantly decreased for all regions (18-75 %, P < 0.001). Collective dose decreased by 30 % and the 75th percentile (diagnostic reference level, DRL) by 20-78 %. The audit process resulted in long-lasting dose reduction, with DRLs reduced by 20-78 %, mean DLP/examination by 18-75 %, and collective dose by 30 %. (orig.)

  12. Multidetector CT radiation dose optimisation in adults: short- and long-term effects of a clinical audit

    Energy Technology Data Exchange (ETDEWEB)

    Tack, Denis [EpiCURA Hospital, Clinique Louis Caty, Department of Radiology, Baudour (Belgium); Jahnen, Andreas; Kohler, Sarah [CRP Henri Tudor, Luxembourg (Luxembourg); Harpes, Nico; Back, Carlo [Ministry of Health, Department of Radiation Protection, Luxembourg (Luxembourg); Maertelaer, Viviane de [Universite libre de Bruxelles, Institut de Recherche Interdisciplinaire en Biologie Humaine et Moleculaire and SBIM, Statistical Unit, Brussels (Belgium); Gevenois, Pierre Alain [Hopital Erasme, Department of Radiology, Brussels (Belgium)

    2014-01-15

    To report short- and long-term effects of an audit process intended to optimise the radiation dose from multidetector row computed tomography (MDCT). A survey of radiation dose from all eight MDCT departments in the state of Luxembourg performed in 2007 served as baseline, and involved the most frequently imaged regions (head, sinus, cervical spine, thorax, abdomen, and lumbar spine). CT dose index volume (CTDIvol), dose-length product per acquisition (DLP/acq), and DLP per examination (DLP/exa) were recorded, and their mean, median, 25th and 75th percentiles compared. In 2008, an audit conducted in each department helped to optimise doses. In 2009 and 2010, two further surveys evaluated the audit's impact on the dose delivered. Between 2007 and 2009, DLP/exa significantly decreased by 32-69 % for all regions (P < 0.001) except the lumbar spine (5 %, P = 0.455). Between 2009 and 2010, DLP/exa significantly decreased by 13-18 % for sinus, cervical and lumbar spine (P ranging from 0.016 to less than 0.001). Between 2007 and 2010, DLP/exa significantly decreased for all regions (18-75 %, P < 0.001). Collective dose decreased by 30 % and the 75th percentile (diagnostic reference level, DRL) by 20-78 %. The audit process resulted in long-lasting dose reduction, with DRLs reduced by 20-78 %, mean DLP/examination by 18-75 %, and collective dose by 30 %. (orig.)

  13. Multi-detector spiral CT study of the relationships between pulmonary ground-glass nodules and blood vessels

    Energy Technology Data Exchange (ETDEWEB)

    Gao, Feng; Li, Ming; Ge, Xiaojun; Ren, Qingguo; Hua, Yanqing [Huadong Hospital Fudan University, Department of Radiology, Shanghai (China); Zheng, Xiangpeng [Huadong Hospital Fudan University, Department of Radiation Oncology, Shanghai (China); Chen, Yan [Huadong Hospital Fudan University, Department of Pathology, Shanghai (China); Lv, Fangzhen [Huadong Hospital Fudan University, Department of Thoracic Surgery, Shanghai (China)

    2013-12-15

    To investigate the relationships between pulmonary ground-glass nodules (GGN) and blood vessels and their diagnostic values in differentiating GGNs. Multi-detector spiral CT imaging of 108 GGNs was retrospectively reviewed. The spatial relationships between GGNs and supplying blood vessels were categorized into four types: I, vessels passing by GGNs; II, intact vessels passing through GGNs; III, distorted, dilated or tortuous vessels seen within GGNs; IV, more complicated vasculature other than described above. Relationship types were correlated to pathologic and/or clinical findings of GGNs. Of 108 GGNs, 10 were benign, 24 preinvasive nodules and 74 adenocarcinomas that were pathologically proven. Types I, II, III and IV vascular relationships were observed in 9, 58, 21 and 20 GGNs, respectively. Type II relationship was the dominating relationship for each GGN group, but significant differences were shown among them. Correlation analysis showed strong correlation between invasive adenocarcinoma and type III and IV relationships. Subgroup analysis indicated that type III was more commonly seen in IAC with comparison to type IV more likely seen in MIA. Different GGNs have different relationships with vessels. Understanding and recognising characteristic GGN-vessel relationships may help identify which GGNs are more likely to be malignant. (orig.)

  14. Strategies to reduce radiation dose in cardiac PET/CT

    Science.gov (United States)

    Wu, Tung Hsin; Wu, Nien-Yun; Wang, Shyh-Jen; Wu, Jay; S. P. Mok, Greta; Yang, Ching-Ching; Huang, Tzung-Chi

    2011-08-01

    Our aim was to investigate CT dose reduction strategies on a hybrid PET/CT scanner for cardiac applications.MaterialsImage quality and dose estimation of different CT scanning protocols for CT coronary angiography (CTCA), and CT-based attenuation correction for PET imaging were investigated. Fifteen patients underwent CTCA, perfusion PET imaging at rest and under stress, and FDG PET for myocardial viability. These patients were divided into three groups based on the CTCA technique performed: retrospectively gated helical (RGH), ECG tube current modulation (ETCM), and prospective gated axial (PGA) acquisitions. All emission images were corrected for photon attenuation using CT images obtained by default setting and an ultra-low dose CT (ULDCT) scan.ResultsRadiation dose in RGH technique was 22.2±4.0 mSv. It was reduced to 10.95±0.82 and 4.13±0.31 mSv using ETCM and PGA techniques, respectively. Radiation dose in CT transmission scan was reduced by 96.5% (from 4.53±0.5 to 0.16±0.01 mSv) when applying ULDCT as compared to the default CT. No significant difference in terms of image quality was found among various protocols.ConclusionThe proposed CT scanning strategies, i.e. ETCM or PGA for CTCA and ULDCT for PET attenuation correction, could reduce radiation dose up to 47% without degrading imaging quality in an integrated cardiac PET/CT coronary artery examination.

  15. Evaluation of middle cerebral artery stents using multidetector row CT angiography in vivo study: comparison of the three different kernels

    International Nuclear Information System (INIS)

    Background: There are very few reports assessing middle cerebral artery (MCA) stents using multidetector computed tomography (MDCT). Purpose: To assess MCA stents using multidetector CT angiography (CTA) in vivo evaluation: the differences in the CTA results according to the three different kernels. Material and Methods: We retrospectively evaluated 27 MCA stents from 26 patients who underwent CTA with 16- and 64-slice MDCT after percutaneous transluminal angioplasty and stenting (PTAS). By CTA, using medium-smooth kernel (B30), medium-sharp kernel (B50), and sharp kernel (B60), the lumen diameter, artificial luminal narrowing (ALN), and subjective visibility score of the stented vessels were evaluated. The subjective visibility score ranged from 1 (poor quality) to 5 (excellent) using a five-point scale. Results: There were excellent inter-observer agreements for the lumen diameter measurements (P < 0.001). The mean diameter of the stented vessels was 2.10 ± 0.31 mm on digital subtraction angiography (DSA), 0.93 ± 0.20 mm on CTA using B30, 1.18 ± 0.27 mm on CTA using B50, and 1.29 ± 0.29 mm on CTA using B60. The mean ALN was 55.7 ± 6.0% on CTA using B30, 43.8 ± 7.5% on CTA using B50, and 38.7 ± 8.3% on CTA using B60. CTA with higher kernels had a smaller ALN than images with smaller kernels. The median subjective visibility score on the CTA using B50 was 3, which was higher than for the other kernels. The differences in the lumen diameter, ALN, and the subjective visibility score of the stented vessels on CTA using the three different kernels was statistically significant (P < 0.001). Conclusion: The sharp kernel was better to assess the lumen diameter and ALN, but was inferior to the medium-sharp kernel for in-stent evaluation due to high image-to-noise. CTA with medium-sharp kernel showed good lumen visibility and acceptable ALN for MCA stents. This could therefore be a non-invasive, readily applicable clinical method for assessing MCA stent patency after

  16. Evaluation of middle cerebral artery stents using multidetector row CT angiography in vivo study: comparison of the three different kernels

    Energy Technology Data Exchange (ETDEWEB)

    Jang, Jin Hee; Lim, Yeon Soo; Lee, Youn Joo; Yoo, Won Jong; Sung, Mi Sook (Dept. of Radiology, Bucheon St Mary' s Hospital, Coll. of Medicine, The Catholic Univ. of Korea, Bucheon (Korea, Republic of)), email: wjyu@catholic.ac.kr; Kim, Bum Soo (Dept. of Radiology, Seoul St Mary' s Hospital, Coll. of Medicine, The Catholic Univ. of Korea, Seoul (Korea, Republic of))

    2012-05-15

    Background: There are very few reports assessing middle cerebral artery (MCA) stents using multidetector computed tomography (MDCT). Purpose: To assess MCA stents using multidetector CT angiography (CTA) in vivo evaluation: the differences in the CTA results according to the three different kernels. Material and Methods: We retrospectively evaluated 27 MCA stents from 26 patients who underwent CTA with 16- and 64-slice MDCT after percutaneous transluminal angioplasty and stenting (PTAS). By CTA, using medium-smooth kernel (B30), medium-sharp kernel (B50), and sharp kernel (B60), the lumen diameter, artificial luminal narrowing (ALN), and subjective visibility score of the stented vessels were evaluated. The subjective visibility score ranged from 1 (poor quality) to 5 (excellent) using a five-point scale. Results: There were excellent inter-observer agreements for the lumen diameter measurements (P < 0.001). The mean diameter of the stented vessels was 2.10 +- 0.31 mm on digital subtraction angiography (DSA), 0.93 +- 0.20 mm on CTA using B30, 1.18 +- 0.27 mm on CTA using B50, and 1.29 +- 0.29 mm on CTA using B60. The mean ALN was 55.7 +- 6.0% on CTA using B30, 43.8 +- 7.5% on CTA using B50, and 38.7 +- 8.3% on CTA using B60. CTA with higher kernels had a smaller ALN than images with smaller kernels. The median subjective visibility score on the CTA using B50 was 3, which was higher than for the other kernels. The differences in the lumen diameter, ALN, and the subjective visibility score of the stented vessels on CTA using the three different kernels was statistically significant (P < 0.001). Conclusion: The sharp kernel was better to assess the lumen diameter and ALN, but was inferior to the medium-sharp kernel for in-stent evaluation due to high image-to-noise. CTA with medium-sharp kernel showed good lumen visibility and acceptable ALN for MCA stents. This could therefore be a non-invasive, readily applicable clinical method for assessing MCA stent patency after

  17. Evaluation of right ventricular volume and mass using retrospective ECG-gated cardiac multidetector computed tomography: comparison with first-pass radionuclide angiography

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Tae Hoon [Yonsei University College of Medicine, Department of Radiology, Seoul (Korea); Yongdong Severance Hospital, Department of Radiology, Seoul (Korea); Ryu, Young Hoon; Hur, Jin; Kim, Sang Jin; Kim, Hyun Soo; Choi, Byoung Wook [Yonsei University College of Medicine, Department of Radiology, Seoul (Korea); Kim, Young; Kim, Hyung Jung [Yonsei University College of Medicine, Department of Pulmonology, Seoul (Korea)

    2005-09-01

    The purposes of this study were to evaluate the right ventricular (RV) volume and mass using cardiac multidetector computed tomography (MDCT) and to compare the cardiac MDCT results with those from first-pass radionuclide angiography (FPRA). Twenty patients were evaluated for the RV end-diastolic volume (RVEDV), the RV end-systolic volume (RVESV), the RV ejection fraction (RVEF), and RV mass using cardiac MDCT with a two-phase reconstruction method based on ECG. The end-diastolic phase was reconstructed at the starting point of the QRS complex on ECG, and the end-systolic phase was reconstructed at the halfway point of the ascending T-wave on ECG. The RV mass was measured for the end-systole. The RVEF was also obtained by FPRA. The mean RVEF (47{+-}7%) measured by cardiac MDCT was well correlated with that (44{+-}6%) measured by FPRA (r=0.854). A significant difference in the mean RVEF was found between cardiac MDCT and FPRA (p=0.001), with an overestimation of 2.9{+-}5.3% by cardiac MDCT versus FPRA. The interobserver variability was 4.4% for the RVEDV, 6.8% for the RVESV, and 7.9% for the RV mass, respectively. Cardiac MDCT is relatively simple and allows the RV volume and mass to be assessed, and the RVEF obtained by cardiac MDCT correlates well with that measured by FPRA. (orig.)

  18. Primary Cardiac Lymphoma: Helical CT Findings and Radiopathologic Correlation

    International Nuclear Information System (INIS)

    Primary tumors of the heart are extremely rare.Clinical manifestations are nondiagnostic and the patients are often misdiagnosed. Magnetic resonance imaging and echocardiography are standard in this diagnostic workup. We report a case of a man with acromegaly, dysphagia, chest pain and weight loss. An invasive cardiac mass was diagnosed by helical-CT. Autopsy demonstrated a B-cell aggressive lymphoma

  19. Low-dose multidetector-row CT-angiography of abdominal aortic aneurysm after endovascular repair

    Energy Technology Data Exchange (ETDEWEB)

    Iezzi, R., E-mail: iezzir@virgilio.it [Department of Bioimaging and Radiological Sciences, Institute of Radiology, ' A. Gemelli' Hospital - Catholic University, L.go A Gemelli 8, 00168 Rome (Italy); Department of Clinical Science and Bioimaging, Section of Radiology, University ' G. D' Annunzio' , Chieti (Italy); Cotroneo, A.R.; Giammarino, A. [Department of Clinical Science and Bioimaging, Section of Radiology, University ' G. D' Annunzio' , Chieti (Italy); Spigonardo, F. [Department of Vascular Surgery, University ' G. D' Annunzio' , Chieti (Italy); Storto, M.L. [Department of Clinical Science and Bioimaging, Section of Radiology, University ' G. D' Annunzio' , Chieti (Italy)

    2011-07-15

    Purpose: To investigate the possibility of reducing radiation dose exposure while maintaining image quality using multidetector computed tomography angiography (MDCTA) with high-concentration contrast media in patients undergoing follow-up after endovascular aortic repair (EVAR) to treat abdominal aortic aneurysm. Materials and methods: In this prospective, single center, intra-individual study, patients underwent two consecutive MDCTA scans 6 months apart, one with a standard acquisition protocol (130 mAs/120 kV) and 120 mL of iomeprol 300, and one using a low dose protocol (100 mAs/80 kV) and 90 mL of iomeprol 400. Images acquired during the arterial phase of contrast enhancement were evaluated both qualitatively and quantitatively for image noise and intraluminal contrast enhancement. Results: Thirty adult patients were prospectively enrolled. Statistically significantly higher attenuation values were measured in the low-dose acquisition protocol compared to the standard protocol, from the suprarenal abdominal aorta to the common femoral artery (p < 0.0001; all vascular segments). Qualitatively, image quality was judged significantly (p = 0.0002) better with the standard protocol than with the low-dose protocol. However, no significant differences were found between the two protocols in terms of contrast-to-noise ratio (CNR) (13.63 {+-} 6.97 vs. 11.48 {+-} 8.13; p = 0.1058). An overall dose reduction of up to 74% was observed for the low-dose protocol compared with the standard protocol. Conclusion: In repeat follow-up examinations of patients undergoing EVAR for abdominal aortic aneurysm, a low-dose radiation exposure acquisition protocol provides substantially reduced radiation exposure while maintaining a constant CNR and good image quality.

  20. Value of oral effervescent powder administration for multidetector CT evaluation of esophageal cancer

    Energy Technology Data Exchange (ETDEWEB)

    Ringe, Kristina I., E-mail: ringe.kristina@mh-hannover.de [Department of Diagnostic and Interventional Radiology, Hannover Medical School, Carl-Neuberg Str. 1, 30625 Hannover (Germany); Meyer, Simone, E-mail: Meyer.simone.rad@mh-hannover.de [Department of Diagnostic and Interventional Radiology, Hannover Medical School, Carl-Neuberg Str. 1, 30625 Hannover (Germany); Ringe, Bastian P., E-mail: Ringe.bastian@mh-hannover.de [Department of General, Visceral and Transplantation Surgery, Hannover Medical School, Carl-Neuberg Str. 1, 30625 Hannover (Germany); Winkler, Michael, E-mail: Winkler.michael@mh-hannover.de [Department of General, Visceral and Transplantation Surgery, Hannover Medical School, Carl-Neuberg Str. 1, 30625 Hannover (Germany); Wacker, Frank, E-mail: Wacker.frank@mh-hannover.de [Department of Diagnostic and Interventional Radiology, Hannover Medical School, Carl-Neuberg Str. 1, 30625 Hannover (Germany); Raatschen, Hans-Juergen, E-mail: Raatschen.hans-juergen@mh-hannover.de [Department of Diagnostic and Interventional Radiology, Hannover Medical School, Carl-Neuberg Str. 1, 30625 Hannover (Germany)

    2015-02-15

    Highlights: • Oral effervescent powder improves esophageal distension and wall assessment at CT. • This technique improves detection and T staging of esophageal cancer at CT. • It can be easily adopted in clinical routine in patients with esophageal pathology. - Abstract: Purpose: To assess the value of oral effervescent powder (EP) for evaluation of esophageal distension, and for detection and staging of esophageal cancer with contrast-enhanced CT. Materials and methods: 84 patients without esophageal pathology and 52 patients with histological confirmed diagnosis of esophageal cancer were included in this prospective IRB-approved study. Half of the patients in both groups received EP prior to CT. Esophageal distension was assessed by planimetry of the inner (IA) and outer area (OA). Two blinded readers evaluated the datasets separately with regard to diagnosis of esophageal cancer (yes/no) and staging (T0-T4), if applicable. Distension results were compared (t-Test). In patients with cancer sensitivity, specificity, NPV and PPV were calculated. CT staging results were compared to histopathology (Cohen-k). Results: IA and IA/OA were significantly larger after EP as compared to the group without EP (p < 0.05). Sensitivity, specificity, NPV and PPV for cancer detection cancer were as follows: 78%/78%, 98%/98%, 95%/95%, 87%/87% with EP; 60%/68%, 98%/98%, 94%/94%, 80%/83% without EP. Staging with EP was good (k = 0.84/0.67) and moderate without EP (k = 0.58/0.59). Conclusions: Administration of EP prior to CT results in good distension of the esophagus, and improves detection and staging of esophageal cancer, as compared to control studies without EP.

  1. Value of oral effervescent powder administration for multidetector CT evaluation of esophageal cancer

    International Nuclear Information System (INIS)

    Highlights: • Oral effervescent powder improves esophageal distension and wall assessment at CT. • This technique improves detection and T staging of esophageal cancer at CT. • It can be easily adopted in clinical routine in patients with esophageal pathology. - Abstract: Purpose: To assess the value of oral effervescent powder (EP) for evaluation of esophageal distension, and for detection and staging of esophageal cancer with contrast-enhanced CT. Materials and methods: 84 patients without esophageal pathology and 52 patients with histological confirmed diagnosis of esophageal cancer were included in this prospective IRB-approved study. Half of the patients in both groups received EP prior to CT. Esophageal distension was assessed by planimetry of the inner (IA) and outer area (OA). Two blinded readers evaluated the datasets separately with regard to diagnosis of esophageal cancer (yes/no) and staging (T0-T4), if applicable. Distension results were compared (t-Test). In patients with cancer sensitivity, specificity, NPV and PPV were calculated. CT staging results were compared to histopathology (Cohen-k). Results: IA and IA/OA were significantly larger after EP as compared to the group without EP (p < 0.05). Sensitivity, specificity, NPV and PPV for cancer detection cancer were as follows: 78%/78%, 98%/98%, 95%/95%, 87%/87% with EP; 60%/68%, 98%/98%, 94%/94%, 80%/83% without EP. Staging with EP was good (k = 0.84/0.67) and moderate without EP (k = 0.58/0.59). Conclusions: Administration of EP prior to CT results in good distension of the esophagus, and improves detection and staging of esophageal cancer, as compared to control studies without EP

  2. Neutron CT with a multi-detector system leading to drastical reduction of the measuring time

    International Nuclear Information System (INIS)

    By means of numerical simulation methods and their verification with measurements it could be shown that such a detector system can be realized for a line beam and 1-2 detectors per cm. With the maximum available beam width of the fast neutron field at the FRM approximately 20 detectors can be used leading to a reduction of the measuring time to 0,5 - 1 hour. A multi detector system for a line beam of thermal neutrons was constructed, tested and used for CT-measurements. This detector system for the measurement of thinner layers with better spatial resolution could be realized. The electronic discrimination between neutrons and gamma rays has been improved. This discrimination was used in all CT-measurements to get transmission values of both kinds of radiation and to reconstruct to complementary CT-images. The use of a polyenergetic radiation causes spectral shifts in the transmission spectrum leading to artifacts in the reconstructed CT-image. The transmission values must be spectral corrected before image reconstruction, because the image artifacts complicate the image evaluation or make it impossible. A new energy selective procedure for the online spectral correction was developed. This method is based on the concept to measure additionally to the integral transmission value his pulse height spectrum and to do the correction depending on the changes in this pulse height spectrum. (orig./HP)

  3. Clinical–radiologic evaluation of the complications of laparoscopic sleeve gastrectomy: Value of multidetector CT

    Directory of Open Access Journals (Sweden)

    Tamir A. Hassan

    2015-12-01

    Conclusions: As LSG is performed increasingly and frequently, it is essential for radiologists to recognize the normal postoperative anatomy and identify the complications of this procedure. CT is an important imaging tool to diagnose suspected complications of laparoscopic sleeve gastrectomy procedure to ensure accurate diagnosis.

  4. A retrospective comparison of smart prep and test bolus multi-detector CT pulmonary angiography protocols

    International Nuclear Information System (INIS)

    Optimal arterial opacification is crucial in imaging the pulmonary arteries using computed tomography (CT). This poses the challenge of precisely timing data acquisition to coincide with the transit of the contrast bolus through the pulmonary vasculature. The aim of this quality assurance exercise was to investigate if a change in CT pulmonary angiography (CTPA) scanning protocol resulted in improved opacification of the pulmonary arteries. Comparison was made between the smart prep protocol (SPP) and the test bolus protocol (TBP) for opacification in the pulmonary trunk. A total of 160 CTPA examinations (80 using each protocol) performed between January 2010 and February 2011 were assessed retrospectively. CT attenuation coefficients were measured in Hounsfield Units (HU) using regions of interest at the level of the pulmonary trunk. The average pixel value, standard deviation (SD), maximum, and minimum were recorded. For each of these variables a mean value was then calculated and compared for these two CTPA protocols. Minimum opacification of 200 HU was achieved in 98% of the TBP sample but only 90% of the SPP sample. The average CT attenuation over the pulmonary trunk for the SPP was 329 (SD = ±21) HU, whereas for the TBP it was 396 (SD = ±22) HU (P = 0.0017). The TBP also recorded higher maximum (P = 0.0024) and minimum (P = 0.0039) levels of opacification. This study has found that a TBP resulted in significantly better opacification of the pulmonary trunk than the SPP

  5. A retrospective comparison of smart prep and test bolus multi-detector CT pulmonary angiography protocols

    Energy Technology Data Exchange (ETDEWEB)

    Suckling, Tara [Medical Imaging Department, Tamworth Rural Referral Hospital, Tamworth, New South Wales (Australia); Smith, Tony [University Department of Rural Health, The University of Newcastle, Tamworth, New South Wales (Australia); Reed, Warren [Discipline of Medical Radiation Sciences, The University of Sydney, Lidcombe (Australia); Medical Imaging Department, Tamworth Rural Referral Hospital, Tamworth, New South Wales (Australia)

    2013-06-15

    Optimal arterial opacification is crucial in imaging the pulmonary arteries using computed tomography (CT). This poses the challenge of precisely timing data acquisition to coincide with the transit of the contrast bolus through the pulmonary vasculature. The aim of this quality assurance exercise was to investigate if a change in CT pulmonary angiography (CTPA) scanning protocol resulted in improved opacification of the pulmonary arteries. Comparison was made between the smart prep protocol (SPP) and the test bolus protocol (TBP) for opacification in the pulmonary trunk. A total of 160 CTPA examinations (80 using each protocol) performed between January 2010 and February 2011 were assessed retrospectively. CT attenuation coefficients were measured in Hounsfield Units (HU) using regions of interest at the level of the pulmonary trunk. The average pixel value, standard deviation (SD), maximum, and minimum were recorded. For each of these variables a mean value was then calculated and compared for these two CTPA protocols. Minimum opacification of 200 HU was achieved in 98% of the TBP sample but only 90% of the SPP sample. The average CT attenuation over the pulmonary trunk for the SPP was 329 (SD = ±21) HU, whereas for the TBP it was 396 (SD = ±22) HU (P = 0.0017). The TBP also recorded higher maximum (P = 0.0024) and minimum (P = 0.0039) levels of opacification. This study has found that a TBP resulted in significantly better opacification of the pulmonary trunk than the SPP.

  6. Measurement of cardiac output from dynamic pulmonary circulation time CT

    Energy Technology Data Exchange (ETDEWEB)

    Yee, Seonghwan, E-mail: Seonghwan.Yee@Beaumont.edu [Department of Radiation Oncology, Beaumont Health System, Royal Oak, Michigan 48073 (United States); Scalzetti, Ernest M. [Department of Radiology, SUNY Upstate Medical University, Syracuse, New York 13210 (United States)

    2014-06-15

    Purpose: To introduce a method of estimating cardiac output from the dynamic pulmonary circulation time CT that is primarily used to determine the optimal time window of CT pulmonary angiography (CTPA). Methods: Dynamic pulmonary circulation time CT series, acquired for eight patients, were retrospectively analyzed. The dynamic CT series was acquired, prior to the main CTPA, in cine mode (1 frame/s) for a single slice at the level of the main pulmonary artery covering the cross sections of ascending aorta (AA) and descending aorta (DA) during the infusion of iodinated contrast. The time series of contrast changes obtained for DA, which is the downstream of AA, was assumed to be related to the time series for AA by the convolution with a delay function. The delay time constant in the delay function, representing the average time interval between the cross sections of AA and DA, was determined by least square error fitting between the convoluted AA time series and the DA time series. The cardiac output was then calculated by dividing the volume of the aortic arch between the cross sections of AA and DA (estimated from the single slice CT image) by the average time interval, and multiplying the result by a correction factor. Results: The mean cardiac output value for the six patients was 5.11 (l/min) (with a standard deviation of 1.57 l/min), which is in good agreement with the literature value; the data for the other two patients were too noisy for processing. Conclusions: The dynamic single-slice pulmonary circulation time CT series also can be used to estimate cardiac output.

  7. Cardiopulmonary manifestations of isolated pulmonary valve infective endocarditis demonstrated with cardiac CT.

    Science.gov (United States)

    Passen, Edward; Feng, Zekun

    2015-01-01

    Right-sided infective endocarditis involving the pulmonary valve is rare. This pictorial essay discusses the use and findings of cardiac CT combined with delayed chest CT and noncontrast chest CT of pulmonary valve endocarditis. Cardiac CT is able to show the full spectrum of right-sided endocarditis cardiopulmonary features including manifestations that cannot be demonstrated by echocardiography.

  8. Automated characterization of normal and pathologic lung tissue by topological texture analysis of multidetector CT

    Science.gov (United States)

    Boehm, H. F.; Fink, C.; Becker, C.; Reiser, M.

    2007-03-01

    Reliable and accurate methods for objective quantitative assessment of parenchymal alterations in the lung are necessary for diagnosis, treatment and follow-up of pulmonary diseases. Two major types of alterations are pulmonary emphysema and fibrosis, emphysema being characterized by abnormal enlargement of the air spaces distal to the terminal, nonrespiratory bronchiole, accompanied by destructive changes of the alveolar walls. The main characteristic of fibrosis is coursening of the interstitial fibers and compaction of the pulmonary tissue. With the ability to display anatomy free from superimposing structures and greater visual clarity, Multi-Detector-CT has shown to be more sensitive than the chest radiograph in identifying alterations of lung parenchyma. In automated evaluation of pulmonary CT-scans, quantitative image processing techniques are applied for objective evaluation of the data. A number of methods have been proposed in the past, most of which utilize simple densitometric tissue features based on the mean X-ray attenuation coefficients expressed in terms of Hounsfield Units [HU]. Due to partial volume effects, most of the density-based methodologies tend to fail, namely in cases, where emphysema and fibrosis occur within narrow spatial limits. In this study, we propose a methodology based upon the topological assessment of graylevel distribution in the 3D image data of lung tissue which provides a way of improving quantitative CT evaluation. Results are compared to the more established density-based methods.

  9. Diagnostic comparison of X-ray plain film and 40-multidetector CT in dislocation of carpal bones

    International Nuclear Information System (INIS)

    Objective: To study the imaging manifestations and detecting rates of dislocation of carpal bones on X- ray plain film and 40-multidetector CT (MDCT), to improve the diagnostic accuracy and to reduce the missed diagnosis and misdiagnosis. Materials and Methods: The X -ray plain films, MDCT, volume rendering (VR) and multiplanar reconstruction (MPR) of 21 patients with dislocation of carpal bones were retrospectively studied. 19 cases were male and two were female, mean age 31±7 years old (19-45 years). Dislocation was in left side in 14 cases, in right in seven cases. Result: Eight cases of lunate dislocation, 13 cases of perilunar dislocation, three cases of simple perilunar dislocation, four cases of perilunar dislocation per navicular bone. One case of perilunar dislocation per navicular and triangular bones, three cases of perilunar dislocation per triangular bones, two cases of perilunar dislocation per styloid process of radius. Among the cases with fracture of other carpal bones, the diagnosis of fractures of radial styloid process and navicular bones were correctly detected on X-ray plain film. But in three cases with fracture of triangular bone, the fractures were indetectable or the original place of the bone fragments were unable to determine on X-ray plain film, but could be correctly detected with MDCT and reconstruct technology. Conclusion: Diagnosis of dislocation of carpal bones can be correctly made with X-ray plain film in the most cases. But for the cases with fracture of carpal bones, especially with tiny fracture, X-ray plain film produces high rate of missed diagnosis. MDCT, VR and MPR can accurately show dislocations and fractures in three-dimension having high clinical value. (authors)

  10. Effect of obesity on coronary artery plaque using 64 slice multidetector cardiac computed tomography angiography.

    Science.gov (United States)

    Isma'eel, Hussain; Tellalian, David; Hamirani, Yasmin S; Kadakia, Jigar; Nasir, Khurram; Budoff, Matthew J

    2010-04-30

    Patients with a coronary artery calcification score (CACS) of zero and an intermediate risk of coronary artery disease have been shown to have a low prevalence of non-calcified coronary artery plaque (NCP). 181 consecutive patients with CAC 'zero', undergoing cardiac computed tomography angiography (CCTA) angiography at our center were evaluated. Presence of detectable NCP on CCTA in these patients was 13.8%. Mild non-obstructive disease (50%). Traditional risk factors were not found to be associated with the presence of NCP. However higher body mass index (BMI) was strongly found to be associated with NCP (31.6 in patients with NCP vs. 27.6 kg/m(2) in patients without NCP, pNCP as compared to normal BMI (p<0.05).

  11. Computer-aided detection of lung nodules on multidetector CT in concurrent-reader and second-reader modes: A comparative study

    International Nuclear Information System (INIS)

    Purpose: To compare the reading times and detection performances of radiologists in concurrent-reader and second-reader modes of computer-aided detection (CAD) for lung nodules on multidetector computed tomography (CT). Materials and Methods: Fifty clinical multidetector CT datasets containing nodules up to 20 mm in diameter were retrospectively collected. For the detection and rating of non-calcified nodules larger than 4 mm in diameter, 6 radiologists (3 experienced radiologists and 3 resident radiologists) independently interpreted these datasets twice, once with concurrent-reader CAD and once with second-reader CAD. The reference standard of nodules in the datasets was determined by the consensus of two experienced chest radiologists. The reading times and detection performances in the two modes of CAD were statistically compared, where jackknife free-response receiver operating characteristic (JAFROC) analysis was used for the comparison of detection performances. Results: Two hundreds and seven nodules constituted the reference standard. Reading time was significantly shorter in the concurrent-reader mode than in the second-reader mode, with the mean reading time for the 6 radiologists being 132 s with concurrent-reader CAD and 210 s with second-reader CAD (p < 0.01). JAFROC analysis revealed no significant difference between the detection performances in the two modes, with the average figure-of-merit value for the 6 radiologists being 0.70 with concurrent-reader CAD and 0.72 with second-reader CAD (p = 0.35). Conclusion: In CAD for lung nodules on multidetector CT, the concurrent-reader mode is more time-efficient than the second-reader mode, and there can be no significant difference between the two modes in terms of detection performance of radiologists

  12. Augmenting CT cardiac roadmaps with segmented streaming ultrasound

    Science.gov (United States)

    Duan, Qi; Shechter, Guy; Gutiérrez, Luis F.; Stanton, Douglas; Zagorchev, Lyubomir; Laine, Andrew F.; Elgort, Daniel R.

    2007-03-01

    Static X-ray computed tomography (CT) volumes are often used as anatomic roadmaps during catheter-based cardiac interventions performed under X-ray fluoroscopy guidance. These CT volumes provide a high-resolution depiction of soft-tissue structures, but at only a single point within the cardiac and respiratory cycles. Augmenting these static CT roadmaps with segmented myocardial borders extracted from live ultrasound (US) provides intra-operative access to real-time dynamic information about the cardiac anatomy. In this work, using a customized segmentation method based on a 3D active mesh, endocardial borders of the left ventricle were extracted from US image streams (4D data sets) at a frame rate of approximately 5 frames per second. The coordinate systems for CT and US modalities were registered using rigid body registration based on manually selected landmarks, and the segmented endocardial surfaces were overlaid onto the CT volume. The root-mean squared fiducial registration error was 3.80 mm. The accuracy of the segmentation was quantitatively evaluated in phantom and human volunteer studies via comparison with manual tracings on 9 randomly selected frames using a finite-element model (the US image resolutions of the phantom and volunteer data were 1.3 x 1.1 x 1.3 mm and 0.70 x 0.82 x 0.77 mm, respectively). This comparison yielded 3.70+/-2.5 mm (approximately 3 pixels) root-mean squared error (RMSE) in a phantom study and 2.58+/-1.58 mm (approximately 3 pixels) RMSE in a clinical study. The combination of static anatomical roadmap volumes and dynamic intra-operative anatomic information will enable better guidance and feedback for image-guided minimally invasive cardiac interventions.

  13. Differentiation of a Femoral Hernia from an Inguinal Hernia on Isotropic Multidetector-Row CT (MDCT): the Benefit of Inguinal Ligament Coronal-Oblique Images

    International Nuclear Information System (INIS)

    This study was designed to evaluate the diagnostic value of the use of inguinal ligament coronal-oblique CT images in the differentiation of femoral hernias from inguinal hernias. A total of 32 patients (with 11 femoral hernias and 21 inguinal hernias) underwent CT imaging. All of the examinations were performed with a 16- multidetector row CT (MDCT) scanner with contrast enhancement, and transverse sections, coronal sections and coronal-oblique CT images were reformed along an imaginary inguinal ligament plane. Two independent observers retrospectively evaluated the CT scans. Image analysis was first performed with only transverse and coronal images. A second analysis was then performed with transverse, coronal and coronal- oblique images. The mean angle difference between coronal and coronal-oblique CT images was 8.0 degrees (range, 0-22 degrees). A radiologist correctly diagnosed the presence of a femoral hernia in nine (82%) of 11 patients and a radiology fellow correctly diagnosed the presence of a femoral hernia in seven (64%) of 11 patients in the first session. Both of the reviewers made the correct diagnosis in all patients in the second session. For inguinal hernias, both reviewers correctly diagnosed all patients during both sessions. The coronal-oblique CT images were the most valuable images for the evaluation of the relationship between hernias of the neck and inguinal ligament. Inguinal ligament coronal-oblique CT images can provide additional diagnostic value in the evaluation of groin hernias

  14. Adjustment of lipiodol dose according to tumor blood supply during transcatheter arterial chemoembolization for large hepatocellular carcinoma by multidetector helical CT

    Institute of Scientific and Technical Information of China (English)

    Hong-Yan Cheng; Yi Shou; Xiang Wang; Ai-Min Xu; Dong Chen; Yu-Chen Jia

    2004-01-01

    AIM: To work out an individualized lipiodol dose in transcatheter arterial chemoembolization (TACE) for large hepatocellularcarcinoma (HCC) according to its blood supply evaluated by CT.METHODS: One hundred patients with large HCC (more than 8 cm in diameter) were studied by multidetector helical CT. Patterns of blood supply of HCC were divided into sufficient blood supply, poor blood supply, mixed blood supply and arteriovenous (A-V) shunt. The dose of ultra fluid lipiodol was determined by diameter and blood supply type of HCC. Patients were divided into two groups (50 cases each): lipiodol perfusion group and iodized oil perfusion group according to tumor diameter and the blood supply type of tumor.RESULTS: The confirmation and effective rates were 82%, 84% in the first group and 36%, 46% in the second group (P<0.01).CONCLUSION: A relatively individualized lipiodol dose may be determined according to the blood supply pattern and the tumor diameter by CT imaging.

  15. Pathologic/high-resolution CT correlation of focal lung lesions 5 mm or less in diameter. Detection and identification by multidetector-row CT

    International Nuclear Information System (INIS)

    The purpose of this study was to clarify the limitations of multidetector-row CT (MDCT) in detecting focal lung lesions of 5 mm or less in diameter by pathologic/high-resolution CT (HRCT) correlation. Twenty-two patients who underwent both preoperative HRCT of the entire lobe using MDCT (MD-HRCT) and lobectomy for primary (n=21) or metastatic (n=1) lung tumor were studied. The author attempted to locate any focal lung lesions other than the main tumor throughout the resected and sliced specimens and to identify the opacities corresponding to the macroscopic lesions on MD-HRCT before histopathologic evaluation. Then two observers without pathologic information attempted to detect the lesions on MD-HRCT. Ninety-one lesions of 5 mm or less in diameter were found in 15 patients. Histopathologically, 13 lesions were classified as bronchioloalveolar carcinoma (BAC), 38 as atypical adenomatous hyperplasia (AAH), 9 as reactive hyperplasia (RH), 19 as inflammatory lesion (INF), 8 as solid lesion (SL), and 4 as showing no organizing change. The author, who had knowledge of the gross pathologic examinations, identified the opacities at rates of 100%, 82%, 56%, 42%, and 88% for BAC, AAH, RH, INF, and SL, respectively. The rates of lesion detection in the absence of knowledge of the pathologic examinations were 85%, 58%, 22%, 32%, and 75% for BAC, AAH, RH, INF, and SL, respectively. The rates of identification and detection of lesions more than 3 mm in diameter were 90% and 57%, respectively, while those of lesions less than 2 mm in diameter were 71% and 35%, respectively. MD-HRCT proved to be useful in detecting focal lung lesions of 5 mm or less in diameter; however, it is still difficult to detect lesions of less than 2 mm in diameter. (author)

  16. Crossed Fused Renal Ectopia: Presentations on 99mTc-MAG3 Scan, 99mTc-DMSA SPECT, and Multidetector CT.

    Science.gov (United States)

    Moon, Eun Ha; Kim, Min-Woo; Kim, Young Jun; Sun, In O

    2015-10-01

    Crossed renal ectopia is an uncommon developmental anomaly in which both kidneys are located on the same side of the body. The present case describes a 20-year-old man who underwent the military entrance physical examination. The ultrasound showed the right kidney in normal site with slightly increased size, but the left kidney was not identified. Tc-MAG3 scan showed a single kidney with 2 ureters, and the orifices of the ureters were connected at both sides of bladder. Tc-DMSA SPECT and contrast-enhanced multidetector CT were performed and revealed crossed fused renal ectopia.

  17. Crossed Fused Renal Ectopia: Presentations on 99mTc-MAG3 Scan, 99mTc-DMSA SPECT, and Multidetector CT.

    Science.gov (United States)

    Moon, Eun Ha; Kim, Min-Woo; Kim, Young Jun; Sun, In O

    2015-10-01

    Crossed renal ectopia is an uncommon developmental anomaly in which both kidneys are located on the same side of the body. The present case describes a 20-year-old man who underwent the military entrance physical examination. The ultrasound showed the right kidney in normal site with slightly increased size, but the left kidney was not identified. Tc-MAG3 scan showed a single kidney with 2 ureters, and the orifices of the ureters were connected at both sides of bladder. Tc-DMSA SPECT and contrast-enhanced multidetector CT were performed and revealed crossed fused renal ectopia. PMID:26252333

  18. Measurements of pericardial adipose tissue using contrast enhanced cardiac multidetector computed tomography—comparison with cardiac magnetic resonance imaging

    DEFF Research Database (Denmark)

    Elming, Marie Bayer; Lønborg, Jacob; Rasmussen, Thomas;

    2013-01-01

    Recent studies have suggested that pericardial adipose tissue (PAT) located in close vicinity to the epicardial coronary arteries may play a role in the development of coronary artery disease. PAT has primarily been measured with cardiac magnetic resonance imaging (CMRI) or with non...... tested, and the smallest difference in PAT was noted when -30 to -190 HU were used in MDCT measures. The median difference between MDCT and CMRI for the assessment of PAT was 9 ml (SD 50) suggesting a reasonable robust method for the assessment of PAT in a large-scale study. Pericardial adipose tissue...... and CMRI scans were performed. The optimal fit for measuring PAT using contrast MDCT was developed and validated by the corresponding measures on CMRI. The median for PAT volume in patients was 175 ml (SD 68) and 153 ml (SD 60) measured by MDCT and CMRI respectively. Four different attenuation values were...

  19. Are pancreatic calcifications specific for the diagnosis of chronic pancreatitis? A multidetector-row CT analysis

    Energy Technology Data Exchange (ETDEWEB)

    Campisi, A. [Department of Radiology, University of Palermo, via del Vespro 127, 90127 Palermo (Italy); Brancatelli, G. [Department of Radiology, University of Palermo, via del Vespro 127, 90127 Palermo (Italy); Department of Radiology, University of Pittsburgh School of Medicine, 200 Lothrop street, 15213, Pittsburgh, PA (United States); Radiology Unit, La Maddalena hospital, 90146, Palermo (Italy)], E-mail: gbranca@yahoo.com; Vullierme, M.-P.; Levy, P.; Ruzniewski, P. [Universite Paris 7 Denis Diderot, Paris, F-75018 (France); AP-HP, Hopital Beaujon, Department of Radiology, Clichy F-92100 (France); Vilgrain, V. [Universite Paris 7 Denis Diderot, Paris, F-75018 (France); AP-HP, Hopital Beaujon, Department of Radiology, Clichy F-92100 (France); INSERM, U773, Centre de recherche biomedicale Bichat-Beaujon, CRB3, Paris F-75018 (France)

    2009-09-15

    Aim: To retrospectively establish the most frequently encountered diagnoses in patients with pancreatic calcifications and to investigate whether the association of certain findings could be helpful for diagnosis. Materials and methods: One hundred and three patients were included in the study. The location and distribution of calcifications; presence, nature, and enhancement pattern of pancreatic lesions; pancreatic atrophy and ductal dilatation were recorded. Differences between patients with chronic pancreatitis and patients with other entities were compared by using Fisher's exact test. Results: Patients had chronic pancreatitis (n = 70), neuroendocrine tumours (n = 14), intraductal papillary mucinous neoplasm (n = 11), pancreatic adenocarcinoma (n = 4), serous cystadenoma (n = 4). Four CT findings had a specificity of over 60% for the diagnosis of chronic pancreatitis: parenchymal calcifications, intraductal calcifications, parenchymal atrophy, and cystic lesions. When at least two of these four criteria were used in combination, 54 of 70 (77%) patients with chronic pancreatitis could be identified, but only 17 of 33 (51%) patients with other diseases. When at least three of these four criteria were present, a specificity of 79% for the diagnosis of chronic pancreatitis was achieved. Conclusion: Certain findings are noted more often in chronic pancreatitis than in other pancreatic diseases. The presence of a combination of CT findings can suggest chronic pancreatitis and be helpful in diagnosis.

  20. Utilization of low-dose multidetector CT and virtual bronchoscopy in children with suspected foreign body aspiration

    Energy Technology Data Exchange (ETDEWEB)

    Adaletli, Ibrahim; Kurugoglu, Sebuh; Ulus, Sila; Ozer, Harun; Kantarci, Fatih; Mihmanli, Ismail; Akman, Canan [Istanbul University, Department of Radiology, Cerrahpasa Medical Faculty, Istanbul (Turkey); Elicevik, Mehmet [Istanbul University, Department of Pediatric Surgery, Cerrahpasa Medical Faculty, Istanbul (Turkey)

    2007-01-15

    Foreign body aspiration is common in children, especially those under 3 years of age. Chest radiography and CT are the main imaging modalities for the evaluation of these children. Management of children with suspected foreign body aspiration (SFBA) mainly depends on radiological findings. To investigate the potential use of low-dose multidetector CT (MDCT) and virtual bronchoscopy (VB) in the evaluation and management of SFBA in children. Included in the study were 37 children (17 girls, 20 boys; age 4 months to 10 years, mean 32 months) with SFBA. Chest radiographs were obtained prior to MDCT in all patients. MDCT was performed using a low-dose technique. VB images were obtained in the same session. Conventional bronchoscopy (CB) was performed within 24 h on patients in whom an obstructive abnormality had been found by MDCT and VB. Obstructive pathology was found in 16 (43.25%) of the 37 patients using MDCT and VB. In 13 of these patients, foreign bodies were detected and removed via CB. The foreign bodies were located in the right main bronchus (n = 5), in the bronchus intermedius (n = 6), in the medial segment of the middle lobe bronchus (n = 1), and in the left main bronchus (n = 1). In the remaining three patients, the diagnosis was false-positive for an obstructive pathology by MDCT and VB; the final diagnoses were secretions (n = 2) and schwannoma (n = 1), as demonstrated by CB. In 21 patients in whom no obstructive pathology was detected by MDCT and VB, CB was not performed. These patients were followed for 5-20 months without any recurrent obstructive symptomatology. Low-dose MDCT and VB are non-invasive radiological modalities that can be used easily in the investigation of SFBA in children. MDCT and VB provide the exact location of the obstructive pathology prior to CB. If obstructive pathology is depicted with MDCT and VB, CB should be performed either for confirmation of the diagnosis or for the diagnosis of an alternative cause for the obstruction

  1. Congenital left ventricular wall abnormalities in adults detected by gated cardiac multidetector computed tomography: Clefts, aneurysms, diverticula and terminology problems

    Energy Technology Data Exchange (ETDEWEB)

    Erol, Cengiz, E-mail: drcengizerol@yahoo.com [Selcuk University, Selcuklu Faculty of Medicine, Department of Radiology, Alaeddin Keykubat Central Campus, Selcuklu, 42250 Konya (Turkey); Koplay, Mustafa, E-mail: koplaymustafa@hotmail.com [Selcuk University, Selcuklu Faculty of Medicine, Department of Radiology, Alaeddin Keykubat Central Campus, Selcuklu, 42250 Konya (Turkey); Olcay, Ayhan, E-mail: drayhanolcay@gmail.com [29 May Hospital, Department of Cardiology, Vatan Street, Fatih, 34150 Istanbul (Turkey); Kivrak, Ali Sami, E-mail: alisamikivrak@hotmail.com [Selcuk University, Selcuklu Faculty of Medicine, Department of Radiology, Alaeddin Keykubat Central Campus, Selcuklu, 42250 Konya (Turkey); Ozbek, Seda, E-mail: dsadr@hotmail.com [Selcuk University, Selcuklu Faculty of Medicine, Department of Radiology, Alaeddin Keykubat Central Campus, Selcuklu, 42250 Konya (Turkey); Seker, Mehmet, E-mail: hikmet.irfan@hotmail.com [29 May Hospital, Department of Radiology, Vatan Street, Fatih, 34150 Istanbul (Turkey); Paksoy, Yahya, E-mail: yahyapaksoy@yahoo.com [Selcuk University, Selcuklu Faculty of Medicine, Department of Radiology, Alaeddin Keykubat Central Campus, Selcuklu, 42250 Konya (Turkey)

    2012-11-15

    Objectives: Our aim was to evaluate congenital left ventricular wall abnormalities (clefts, aneurysms and diverticula), describe and illustrate imaging features, discuss terminology problems and determine their prevalence detected by cardiac CT in a single center. Materials and methods: Coronary CT angiography images of 2093 adult patients were evaluated retrospectively in order to determine congenital left ventricular wall abnormalities. Results: The incidence of left ventricular clefts (LVC) was 6.7% (141 patients) and statistically significant difference was not detected between the sexes regarding LVC (P = 0.5). LVCs were single in 65.2% and multiple in 34.8% of patients. They were located at the basal to mid inferoseptal segment of the left ventricle in 55.4%, the basal to mid anteroseptal segment in 24.1%, basal to mid inferior segment in 17% and septal-apical septal segment in 3.5% of cases. The cleft length ranged from 5 to 22 mm (mean 10.5 mm) and they had a narrow connection with the left ventricle (mean 2.5 mm). They were contractile with the left ventricle and obliterated during systole. Congenital left ventricular septal aneurysm that was located just under the aortic valve was detected in two patients (0.1%). No case of congenital left ventricular diverticulum was detected. Conclusion: Cardiac CT allows us to recognize congenital left ventricular wall abnormalities which have been previously overlooked in adults. LVC is a congenital structural variant of the myocardium, is seen more frequently than previously reported and should be differentiated from aneurysm and diverticulum for possible catastrophic complications of the latter two.

  2. In vitro evaluation of 56 coronary artery stents by 256-slice multi-detector coronary CT

    Energy Technology Data Exchange (ETDEWEB)

    Steen, Henning, E-mail: henning.steen@med.uni-heidelberg.de [University of Heidelberg, Department of Cardiology, Im Neuenheimer Feld 410, Heidelberg 69120 (Germany); Andre, Florian, E-mail: Florian.Andre@med.uni-heidelberg.de [University of Heidelberg, Department of Cardiology, Im Neuenheimer Feld 410, Heidelberg 69120 (Germany); Korosoglou, Grigorios, E-mail: Grigorios.Korosoglou@med.uni-heidelberg.de [University of Heidelberg, Department of Cardiology, Im Neuenheimer Feld 410, Heidelberg 69120 (Germany); Mueller, Dirk, E-mail: Dirk.Mueller@philips.com [Philips GmbH Healthcare Division, Luebeckertordamm 5, Hamburg 20099 (Germany); Hosch, Waldemar, E-mail: Waldemar.Hosch@med.uni-heidelberg.de [University of Heidelberg, Department of Diagnostic and Interventional Radiology, Im Neuenheimer Feld 410, Heidelberg 69120 (Germany); Kauczor, Hans-Ulrich, E-mail: Hans-Ulrich.Kauczor@med.uni-heidelberg.de [University of Heidelberg, Department of Diagnostic and Interventional Radiology, Im Neuenheimer Feld 410, Heidelberg 69120 (Germany); Giannitsis, Evangelos, E-mail: Evangelos.Giannitsis@med.uni-heidelberg.de [University of Heidelberg, Department of Cardiology, Im Neuenheimer Feld 410, Heidelberg 69120 (Germany); Katus, Hugo A., E-mail: Hugo.Katus@med.uni-heidelberg.de [University of Heidelberg, Department of Cardiology, Im Neuenheimer Feld 410, Heidelberg 69120 (Germany)

    2011-10-15

    Objective: We sought to investigate stent lumen visibility of 56 coronary stents with the newest 256-multi-slice-CT (256-MDCT) technology for different reconstruction algorithms in an in vitro model. Background: Early identification of in-stent restenosis (ISR) is important to avoid recurrent ischemia and prevent acute myocardial infarction (AMI). Since angiography has the disadvantage of high costs and its invasiveness, MDCT could be a convenient and safe non-invasive alternative for detection of ISR. Material and methods: Percentages of in-stent lumen diameter and in-stent signal attenuation (measured as contrast-to-noise ratio (CNR)) of 56 coronary stents (group A {<=}2.5 mm; group B = 2.75-3.0 mm; group C = 3.5-4.0 mm) were evaluated in a coronary vessel in vitro phantom (iodine-filled plastic tubes) employing four different reconstruction algorithms (XCD, CC, CD, XCB) on a novel 256-MDCT (Philips-iCT, collimation = 128 mm x 0.625 mm; rotation time = 270 ms; tube current = 800 mA s with 120 kV). Analysis was conducted with the semi-automatical full-width-at-half-maximum (FWHM) method. P-values <0.05 were regarded statistically significant. Results: In-stent lumen diameter >60% for group C stents was significantly larger and CNR was significantly lower (both p < 0.05) for sharp kernels (CD; XCD) when compared to groups A/B. The FWHM-method showed significantly smaller in-stent lumen diameter (p < 0.05) when compared to the manual method. Conclusion: 256-MDCT could potentially be employed for clinical assessment of stent patency in stents >3.0 mm when analysed with cardio-dedicated sharp kernels, although clinical studies corroborating this claim should be performed. However, stents {<=}3.0 mm reconstructed by soft kernels revealed insufficient in-stent lumen visualisation and should not be used in clinical practice. Further improvements in spatial and temporal image resolution as well as reductions of radiation exposure and image noise have to be accomplished

  3. How accurate is unenhanced multidetector-row CT (MDCT) for localization of renal calculi?

    Energy Technology Data Exchange (ETDEWEB)

    Goetschi, Stefan, E-mail: goetschi@gmx.net [Institute of Radiology, Triemli Hospital, Birmensdorferstrasse 497, 8063 Zuerich (Switzerland); Umbehr, Martin, E-mail: martin.umbehr@triemli.ch [Urology Clinic, Department of Surgery, Triemli Hospital, Birmensdorferstrasse 497, 8063 Zuerich (Switzerland); Ullrich, Stephan, E-mail: stephan.ullrich@triemli.ch [Institute of Radiology, Triemli Hospital, Birmensdorferstrasse 497, 8063 Zuerich (Switzerland); Glenck, Michael, E-mail: michael.glenck@triemli.ch [Institute of Radiology, Triemli Hospital, Birmensdorferstrasse 497, 8063 Zuerich (Switzerland); Suter, Stefan, E-mail: stefan.suter@triemli.ch [Urology Clinic, Department of Surgery, Triemli Hospital, Birmensdorferstrasse 497, 8063 Zuerich (Switzerland); Weishaupt, Dominik, E-mail: dominik.weishaupt@triemli.ch [Institute of Radiology, Triemli Hospital, Birmensdorferstrasse 497, 8063 Zuerich (Switzerland)

    2012-11-15

    Purpose: To investigate the correlation between unenhanced MDCT and intraoperative findings with regard to the exact anatomical location of renal calculi. Design, setting, and participants: Fifty-nine patients who underwent unenhanced MDCT for suspected urinary stone disease, and who underwent subsequent flexible ureterorenoscopy (URS) as treatment of nephrolithiasis were included in this retrospective study. All MDCT data sets were independently reviewed by three observers with different degrees of experience in reading CT. Each observer was asked to indicate presence and exact anatomical location of any calcification within pyelocaliceal system, renal papilla or renal cortex. Results were compared to intraoperative findings which have been defined as standard of reference. Calculi not described at surgery, but present on MDCT data were counted as renal cortex calcifications. Results: Overall 166 calculi in 59 kidneys have been detected on MDCT, 100 (60.2%) were located in the pyelocaliceal system and 66 (39.8%) in the renal parenchyma. Of the 100 pyelocaliceal calculi, 84 (84%) were correctly located on CT data sets by observer 1, 62 (62%) by observer 2, and 71 (71%) by observer 3. Sensitivity/specificity was 90-94% and 50-100% if only pyelocaliceal calculi measuring >4 mm in size were considered. For pyelocaliceal calculi {<=}4 mm in size diagnostic performance of MDCT was inferior. Conclusion: Compared to flexible URS, unenhanced MDCT is accurate for distinction between pyelocaliceal calculi and renal parenchyma calcifications if renal calculi are >4 mm in size. For smaller renal calculi, unenhanced MDCT is less accurate and distinction between a pyelocaliceal calculus and renal parenchyma calcification is difficult.

  4. How accurate is unenhanced multidetector-row CT (MDCT) for localization of renal calculi?

    International Nuclear Information System (INIS)

    Purpose: To investigate the correlation between unenhanced MDCT and intraoperative findings with regard to the exact anatomical location of renal calculi. Design, setting, and participants: Fifty-nine patients who underwent unenhanced MDCT for suspected urinary stone disease, and who underwent subsequent flexible ureterorenoscopy (URS) as treatment of nephrolithiasis were included in this retrospective study. All MDCT data sets were independently reviewed by three observers with different degrees of experience in reading CT. Each observer was asked to indicate presence and exact anatomical location of any calcification within pyelocaliceal system, renal papilla or renal cortex. Results were compared to intraoperative findings which have been defined as standard of reference. Calculi not described at surgery, but present on MDCT data were counted as renal cortex calcifications. Results: Overall 166 calculi in 59 kidneys have been detected on MDCT, 100 (60.2%) were located in the pyelocaliceal system and 66 (39.8%) in the renal parenchyma. Of the 100 pyelocaliceal calculi, 84 (84%) were correctly located on CT data sets by observer 1, 62 (62%) by observer 2, and 71 (71%) by observer 3. Sensitivity/specificity was 90–94% and 50–100% if only pyelocaliceal calculi measuring >4 mm in size were considered. For pyelocaliceal calculi ≤4 mm in size diagnostic performance of MDCT was inferior. Conclusion: Compared to flexible URS, unenhanced MDCT is accurate for distinction between pyelocaliceal calculi and renal parenchyma calcifications if renal calculi are >4 mm in size. For smaller renal calculi, unenhanced MDCT is less accurate and distinction between a pyelocaliceal calculus and renal parenchyma calcification is difficult.

  5. Use of multidetector-row CT colonography for detection of colorectal neoplasia in patients referred via the Department of Health '2-week-wait' initiative

    Energy Technology Data Exchange (ETDEWEB)

    Taylor, S.A.; Halligan, S. E-mail: s.halligan@ic.ac.uk; Saunders, B.P.; Morley, S.; Riesewyk, C.; Atkin, W.; Bartram, C.I

    2003-11-01

    AIM: Patients referred under the Department of Health 2-week wait initiative with symptoms of colorectal cancer frequently undergo whole-colon examination. We investigated the use of computed tomography (CT) colonography as an alternative to colonoscopy in this scenario. MATERIALS AND METHODS: Fifty-four consecutive patients, referred via the 2-week wait initiative and scheduled for colonoscopy, consented to undergo multidetector CT colonography immediately before endoscopy. The site and morphology of any polyp or cancer detected by CT was noted and comparison made with subsequent colonoscopy. RESULTS: Colonoscopy detected polyps or cancer in 29 patients (53.7%). CT colonography prospectively detected 18 of 41 (44%) polyps of 1-5 mm, three of four (75%) polyps of 6-9 mm, four of four (100%) polyps 10 mm or larger, and five of six (83%) cancers. The missed cancer occurred early in the series and was a perceptive error. The overall sensitivity, specificity, positive predictive value and negative predictive value of CT colonography for cancer and polyps 10 mm or greater on a per patient basis were 90, 100, 100 and 98%, respectively. CT detected one renal cancer and one colonic cancer, initially missed due to incomplete colonoscopy. CONCLUSION: CT colonography is a robust technique for investigation of symptomatic patients. The learning curve must be overcome for optimal performance.

  6. Use of multidetector-row CT colonography for detection of colorectal neoplasia in patients referred via the Department of Health '2-week-wait' initiative

    International Nuclear Information System (INIS)

    AIM: Patients referred under the Department of Health 2-week wait initiative with symptoms of colorectal cancer frequently undergo whole-colon examination. We investigated the use of computed tomography (CT) colonography as an alternative to colonoscopy in this scenario. MATERIALS AND METHODS: Fifty-four consecutive patients, referred via the 2-week wait initiative and scheduled for colonoscopy, consented to undergo multidetector CT colonography immediately before endoscopy. The site and morphology of any polyp or cancer detected by CT was noted and comparison made with subsequent colonoscopy. RESULTS: Colonoscopy detected polyps or cancer in 29 patients (53.7%). CT colonography prospectively detected 18 of 41 (44%) polyps of 1-5 mm, three of four (75%) polyps of 6-9 mm, four of four (100%) polyps 10 mm or larger, and five of six (83%) cancers. The missed cancer occurred early in the series and was a perceptive error. The overall sensitivity, specificity, positive predictive value and negative predictive value of CT colonography for cancer and polyps 10 mm or greater on a per patient basis were 90, 100, 100 and 98%, respectively. CT detected one renal cancer and one colonic cancer, initially missed due to incomplete colonoscopy. CONCLUSION: CT colonography is a robust technique for investigation of symptomatic patients. The learning curve must be overcome for optimal performance

  7. Simulation evaluation of quantitative myocardial perfusion assessment from cardiac CT

    Science.gov (United States)

    Bindschadler, Michael; Modgil, Dimple; Branch, Kelley R.; La Riviere, Patrick J.; Alessio, Adam M.

    2014-03-01

    Contrast enhancement on cardiac CT provides valuable information about myocardial perfusion and methods have been proposed to assess perfusion with static and dynamic acquisitions. There is a lack of knowledge and consensus on the appropriate approach to ensure 1) sufficient diagnostic accuracy for clinical decisions and 2) low radiation doses for patient safety. This work developed a thorough dynamic CT simulation and several accepted blood flow estimation techniques to evaluate the performance of perfusion assessment across a range of acquisition and estimation scenarios. Cardiac CT acquisitions were simulated for a range of flow states (Flow = 0.5, 1, 2, 3 ml/g/min, cardiac output = 3,5,8 L/min). CT acquisitions were simulated with a validated CT simulator incorporating polyenergetic data acquisition and realistic x-ray flux levels for dynamic acquisitions with a range of scenarios including 1, 2, 3 sec sampling for 30 sec with 25, 70, 140 mAs. Images were generated using conventional image reconstruction with additional image-based beam hardening correction to account for iodine content. Time attenuation curves were extracted for multiple regions around the myocardium and used to estimate flow. In total, 2,700 independent realizations of dynamic sequences were generated and multiple MBF estimation methods were applied to each of these. Evaluation of quantitative kinetic modeling yielded blood flow estimates with an root mean square error (RMSE) of ~0.6 ml/g/min averaged across multiple scenarios. Semi-quantitative modeling and qualitative static imaging resulted in significantly more error (RMSE = ~1.2 and ~1.2 ml/min/g respectively). For quantitative methods, dose reduction through reduced temporal sampling or reduced tube current had comparable impact on the MBF estimate fidelity. On average, half dose acquisitions increased the RMSE of estimates by only 18% suggesting that substantial dose reductions can be employed in the context of quantitative myocardial

  8. Upper abdominal gadoxetic acid-enhanced and diffusion-weighted MRI for the detection of gastric cancer: Comparison with two-dimensional multidetector row CT

    International Nuclear Information System (INIS)

    Aim: To evaluate the diagnostic performance of abdominal magnetic resonance imaging (MRI) for the detection of gastric cancer in comparison with that of two-dimensional (2D) multidetector row computed tomography (CT). Materials and methods: The study included 189 patients with 170 surgically confirmed gastric cancers and 19 patients without gastric cancer, all of whom underwent gadoxetic acid-enhanced MRI with diffusion-weighted (DW) imaging, and multidetector contrast-enhanced abdominal CT imaging. Two observers independently analysed three sets of images (CT set, conventional MRI set, and combined conventional and DW MRI set). A five-point scale for likelihood of gastric cancer was used. Diagnostic accuracy, sensitivity, specificity, positive predictive value, and negative predictive value were evaluated. Quantitative [apparent diffusion coefficient (ADC) analyses with Mann–Whitney U-test were conducted for gastric cancers and the nearby normal gastric wall. Results: The diagnostic accuracy and sensitivity for detection of gastric cancer were significantly higher on combined conventional and DW MRI set (77.8–78.3%; 75.3–75.9%) than the CT imaging set (67.7–71.4%; 64.1–68.2%) or the conventional MRI set (72–73%; 68.8–70%; p < 0.01). In particular, for gastric cancers with pT2 and pT3, the combined conventional and DW MRI set (91.6–92.6%) yielded significantly higher sensitivity for detection of gastric cancer than did the CT imaging set (76.8–81.1%) by both observers (p < 0.01). The mean ADC of gastric cancer lesions (1 ± 0.23 × 10−3mm2/s) differed significantly from that of normal gastric wall (1.77 ± 0.25 × 10−3 mm2/s; p < 0.01). Conclusion: Abdominal MRI with DW imaging was more sensitive for the detection of gastric cancer than 2D-multidetector row CT or conventional MRI alone. - Highlights: • The sensitivity for detection of gastric cancer is high on abdominal MR imaging. • DW imaging is helpful for detection of

  9. Noncardiac findings on cardiac CT part I: Pros and cons.

    LENUS (Irish Health Repository)

    Killeen, Ronan P

    2012-02-01

    Cardiac computed tomography (CT) has evolved into an effective imaging technique for the evaluation of coronary artery disease in selected patients. Two distinct advantages over other noninvasive imaging modalities include its ability to evaluate directly the coronary arteries and to provide an opportunity to evaluate extracardiac structures, such as the lungs and mediastinum. Some centers reconstruct a small field of view (FOV) cropped around the heart, but a full FOV (from skin to skin in the irradiated area) is obtainable in the raw data of every scan so that clinically relevant noncardiac findings are identifiable. Debate in the scientific community has centered on the necessity for this large FOV evaluation. A review of noncardiac structures provides the opportunity to make alternative diagnoses that may account for the patient\\'s presentation or to detect important but clinically silent problems such as lung cancer. Critics argue that the yield of biopsy-proven cancers is low and that the follow-up of incidental noncardiac findings is expensive, resulting in increased radiation exposure and possibly unnecessary further testing. In this two-part review we outline the issues surrounding the concept of the noncardiac read looking for noncardiac findings on cardiac CT. Part I focuses on the pros and cons of the practice of identifying noncardiac findings on cardiac CT.

  10. Multidetector CT and MRI in diseases of the GI tract; Scanner multidetecteur face a l'IRM dans la pathologie du tube digestif

    Energy Technology Data Exchange (ETDEWEB)

    Bruel, J.M.; Gallix, B. [Hopital Saint-Eloi, Service de Radiologie, 34 - Montpellier (France)

    2003-04-01

    With the introduction of spiral scanning then multidetector technologies, the accuracy for diagnosing digestive tract diseases with CT has been highly improved, and CT is used more and more in the evaluation of patients with suspected gastrointestinal disorders. CT is able to demonstrate both the intramural and the extra-mural components of the disease, and has a major role in the preoperative staging and the follow-up Improvements of CT protocols, such as CT-enteroclysis, or multiplanar 2D and 3D post-processing, including now techniques for 'virtual endoscopy', lead to discuss new indications in which CT could now compete with conventional X-rays series and video-endoscopy. This precise study of the digestive wall, the peri-digestive fat, the digestive tract blood supply, may be performed by MRI, under the condition of access to high level machines and standardized protocols. MR-enteroclysis and MR-virtual colonoscopy could be performed with much lower risk for the patient, in terms of radiation dose or contrast adverse effects. Endo-luminal coils should give to MR an ultra-high resolution for analysing the different layers of the gastrointestinal wall. Learning objectives: to review how to perform CT and MRI protocols for digestive tract imaging, to recognize the CT arid MR patterns of the main digestive tract diseases, to discuss the value, limits and role of CT and MR in digestive tract diseases, to discuss the potential role of CT and MR new technological developments for digestive tract imaging in the upcoming future Conclusion: CT is nowadays a modality of choice for digestive imaging. Improvements in technologies and indications, the necessary discussion of the risks and benefits for the patient should let the radiologists consider MRI in gastrointestinal disorders as an important part of the routine activity in clinical MRI. (authors)

  11. Multidetector-CT angiography in pulmonary embolism - can image parameters predict clinical outcome?

    Energy Technology Data Exchange (ETDEWEB)

    Heyer, Christoph M.; Lemburg, Stefan P.; Nicolas, Volkmar; Roggenland, Daniela [Berufsgenossenschaftliches Universitaetsklinikum Bergmannsheil GmbH, Ruhr-University of Bochum, Institute of Diagnostic Radiology, Interventional Radiology and Nuclear Medicine, Bochum (Germany); Knoop, Heiko [Berufsgenossenschaftliches Universitaetsklinikum Bergmannsheil GmbH, Medical Clinic III - Pneumology, Allergology, and Sleep Medicine, Bochum (Germany); Holland-Letz, Tim [Ruhr-University of Bochum, Department of Medical Informatics, Biometry and Epidemiology, Bochum (Germany)

    2011-09-15

    To assess if pulmonary CT angiography (CTA) can predict outcome in patients with pulmonary embolism (PE). Retrospective analysis of CTA studies of patients with PE and documentation of pulmonary artery (PA)/aorta ratio, right ventricular (RV)/left ventricular (LV) ratio, superior vena cava (SVC) diameter, pulmonary obstruction index (POI), ventricular septal bowing (VSB), venous contrast reflux (VCR), pulmonary infarction and pleural effusion. Furthermore, duration of total hospital stay, necessity for/duration of ICU therapy, necessity for mechanical ventilation and mortality were recorded. Comparison was performed by logistic/linear regression analysis with significance at 5%. 152 patients were investigated. Mean duration of hospital stay was 21 {+-} 24 days. 66 patients were admitted to the ICU; 20 received mechanical ventilation. Mean duration of ICU therapy was 3 {+-} 8 days. Mortality rate was 8%. Significant positive associations of POI, VCR and pulmonary infarction with necessity for ICU therapy were shown. VCR was significantly associated with necessity for mechanical ventilation and duration of ICU treatment. Pleural effusions were significantly associated with duration of total hospital stay whereas the RV/LV ratio correlated with mortality. Selected CTA findings showed significant associations with the clinical course of PE and may thus be used as predictive parameters. (orig.)

  12. Effect of computer-aided detection as a second reader in multidetector-row CT colonography

    International Nuclear Information System (INIS)

    Our purpose was to assess the effect of computer-aided detection (CAD) on lesion detection as a second reader in computed tomographic colonography, and to compare the influence of CAD on the performance of readers with different levels of expertise. Fifty-two CT colonography patient data-sets (37 patients: 55 endoscopically confirmed polyps ≥0.5 cm, seven cancers; 15 patients: no abnormalities) were retrospectively reviewed by four radiologists (two expert, two nonexpert). After primary data evaluation, a second reading augmented with findings of CAD (polyp-enhanced view, Siemens) was performed. Sensitivities and reading time were calculated for each reader without CAD and supported by CAD findings. The sensitivity of expert readers was 91% each, and of nonexpert readers, 76% and 75%, respectively, for polyp detection. CAD increased the sensitivity of expert readers to 96% (P = 0.25) and 93% (P = 1), and that of nonexpert readers to 91% (P = 0.008) and 95% (P = 0.001), respectively. All four readers diagnosed 100% of cancers, but CAD alone only 43%. CAD increased reading time by 2.1 min (mean). CAD as a second reader significantly improves sensitivity for polyp detection in a high disease prevalence population for nonexpert readers. CAD causes a modest increase in reading time. CAD is of limited value in the detection of cancer. (orig.)

  13. Multidetector-CT angiography in pulmonary embolism - can image parameters predict clinical outcome?

    International Nuclear Information System (INIS)

    To assess if pulmonary CT angiography (CTA) can predict outcome in patients with pulmonary embolism (PE). Retrospective analysis of CTA studies of patients with PE and documentation of pulmonary artery (PA)/aorta ratio, right ventricular (RV)/left ventricular (LV) ratio, superior vena cava (SVC) diameter, pulmonary obstruction index (POI), ventricular septal bowing (VSB), venous contrast reflux (VCR), pulmonary infarction and pleural effusion. Furthermore, duration of total hospital stay, necessity for/duration of ICU therapy, necessity for mechanical ventilation and mortality were recorded. Comparison was performed by logistic/linear regression analysis with significance at 5%. 152 patients were investigated. Mean duration of hospital stay was 21 ± 24 days. 66 patients were admitted to the ICU; 20 received mechanical ventilation. Mean duration of ICU therapy was 3 ± 8 days. Mortality rate was 8%. Significant positive associations of POI, VCR and pulmonary infarction with necessity for ICU therapy were shown. VCR was significantly associated with necessity for mechanical ventilation and duration of ICU treatment. Pleural effusions were significantly associated with duration of total hospital stay whereas the RV/LV ratio correlated with mortality. Selected CTA findings showed significant associations with the clinical course of PE and may thus be used as predictive parameters. (orig.)

  14. Multimodal Registration of gated cardiac PET, CT and MR sequences

    International Nuclear Information System (INIS)

    The research described in this manuscript deals with the multimodal registration of cardiac images from Magnetic Resonance Imaging (MRI), Position Emission Tomography (PET) and Computerized Tomography (CT). All these modalities are gated to the Electrocardiogram (ECG) and provide information to evaluate cardiac function, and to diagnose and to follow-up cardiovascular pathologies. PET imaging allows the evaluation of ventricular function and MRI is a gold standard for the study of the left ventricular function. The goal of our registration process is to merge functional (from PET) and anatomical images (from CT and MRI). Our process is adapted to the modalities used and is divided in two steps: (i) a global rigid 3-dimensional model-based ICP (Iterative Closest Point) registration between CT and MR data and (ii) an iconic 2-dimensional registration based on Free Form Deformations and Mutual Information. This last step presents an original contribution by using a composite image of CT (which presents epicardic contours) and PET (where endocardic contours are partially visible) data to make mutual information more accurate in representing the similarity with the MR data. To speed up the whole process, we also present a transformation initialization scheme using displacement field obtained form MR data only. The obtained results have been evaluated by experts. (author)

  15. Mediastinite aguda: aspectos de imagem pós-cirurgias cardíacas na tomografia computadorizada de multidetectores Acute mediastinitis: multidetector computed tomography findings following cardiac surgery

    Directory of Open Access Journals (Sweden)

    Clarissa Aguiar de Macedo

    2008-08-01

    Full Text Available Mediastinite pós-cirurgias torácicas é definida como a infecção dos órgãos e tecidos do espaço mediastinal, ocorrendo em 0,4% a 5% dos casos. A gravidade da infecção pós-operatória varia desde infecção de tecidos superficiais da parede torácica até mediastinite fulminante com envolvimento esternal. O critério diagnóstico da tomografia computadorizada para mediastinite aguda pós-cirúrgica é a presença de coleção mediastinal, podendo estar associada ou não a anormalidades periesternais como edema/borramento de partes moles, separação dos segmentos esternais com reabsorção óssea marginal, esclerose e osteomielite. Achados associados incluem linfonodomegalias, consolidações pulmonares e derrame pleural e pericárdico. Pequenas coleções e gás mediastinais podem ser usualmente encontradas em pós-operatório recente de cirurgias torácicas sem a presença de infecções, limitando a eficácia da tomografia computadorizada nas duas primeiras semanas. Após esse período, a tomografia alcança quase 100% de sensibilidade e especificidade. Pacientes com suspeita clínica de mediastinite devem ser submetidos a exame de tomografia para pesquisa de coleções, identificando a extensão da doença e sua natureza. A versão de multidetectores propicia recursos de reconstruções em diversos planos e janelas, contribuindo especialmente para o estudo do esterno.Postoperative mediastinitis is defined as an infection of the organs and tissues in the mediastinal space, with an incidence ranging between 0.4% and 5% of cases. This disease severity varies from infection of superficial tissues in the chest wall to fulminant mediastinitis with sternal involvement. Diagnostic criterion for postoperative detection of acute mediastinitis at computed tomography is the presence of fluid collections and gas in the mediastinal space, which might or might not be associated with peristernal abnormalities such as edema of soft tissues

  16. Dynamic multidetector CT and non-contrast-enhanced MR for right adrenal vein imaging: comparison with catheter venography in adrenal venous sampling

    Energy Technology Data Exchange (ETDEWEB)

    Ota, Hideki; Seiji, Kazumasa; Kawabata, Masahiro; Satani, Nozomi; Matsuura, Tomonori; Tominaga, Junya; Takase, Kei [Tohoku University Hospital, Department of Diagnostic Radiology, Sendai (Japan); Omata, Kei; Ono, Yoshikiyo; Iwakura, Yoshitsugu; Morimoto, Ryo; Kudo, Masataka; Satoh, Fumitoshi; Ito, Sadayoshi [Tohoku University Hospital, Division of Nephrology, Endocrinology and Vascular Medicine, Sendai (Japan)

    2016-03-15

    To evaluate visualization of the right adrenal vein (RAV) with multidetector CT and non-contrast-enhanced MR imaging in patients with primary aldosteronism. A total of 125 patients (67 men) scheduled for adrenal venous sampling (AVS) were included. Dynamic 64-detector-row CT and balanced steady-state free precession-based non-contrast-enhanced 3-T MR imaging were performed. RAV visualization based on a four-point score was documented. Both anatomical location and variation on cross-sectional imaging were evaluated, and the findings were compared with catheter venography as the gold standard. The RAV was visualized in 93.2 % by CT and 84.8 % by MR imaging (p = 0.02). Positive predictive values of RAV visualization were 100 % for CT and 95.2 % for MR imaging. Imaging score was significantly higher in CT than MR imaging (p < 0.01). The RAV formed a common trunk with an accessory hepatic vein in 16 % of patients. The RAV orifice level on cross-sectional imaging was concordant with catheter venography within the range of 1/3 vertebral height in >70 % of subjects. Success rate of AVS was 99.2 %. Dynamic CT is a reliable way to map the RAV prior to AVS. Non-contrast-enhanced MR imaging is an alternative when there is a risk of complication from contrast media or radiation exposure. (orig.)

  17. Multi-detector CT-colonography in inflammatory bowel disease: Prospective analysis of CT-findings to high-resolution video colonoscopy

    Energy Technology Data Exchange (ETDEWEB)

    Andersen, Kjel [Institute of Diagnostic Radiology, University Hospital Duesseldorf (Germany)]. E-mail: kjel_andersen@web.de; Vogt, Christoph [Department of Gastroenterology, Hepatology and Infectiology, University Hospital Duesseldorf (Germany); Blondin, Dirk [Institute of Diagnostic Radiology, University Hospital Duesseldorf (Germany); Beck, Andreas [Institute of Informatics, Heinrich-Heine-University, Duesseldorf (Germany); Heinen, Wolfram [Institute of Diagnostic Radiology, University Hospital Duesseldorf (Germany); Aurich, Volker [Institute of Informatics, Heinrich-Heine-University, Duesseldorf (Germany); Haeussinger, Dieter [Department of Gastroenterology, Hepatology and Infectiology, University Hospital Duesseldorf (Germany); Moedder, Ulrich [Institute of Diagnostic Radiology, University Hospital Duesseldorf (Germany); Cohnen, Mathias [Institute of Diagnostic Radiology, University Hospital Duesseldorf (Germany)

    2006-04-15

    Aim: Prospective analysis of multi-detector CT-colonography (MDCTC) in patients with inflammatory bowel disease (IBD) compared to high-resolution video-endoscopy (HRVC). Materials and methods: Twenty-one patients (mean age 49.6 years) with Crohn's disease or ulcerative colitis underwent MDCTC (Somatom Volume Zoom, Siemens, Erlangen; 1 mm collimation, Pitch 8, 100 mAs, 120 kVp). HRVC was performed within 2 h after MDCTC. MDCTC was analyzed by two blinded readers. MDCTC-findings including bowel wall alterations and extraintestinal changes were compared to results of HRVC. Results: Over-all-sensitivity was 100% for endoluminal lesions with correct diagnosis of two cancers. Acute and chronic IBD were correctly identified by MDCTC in 63.6%, and 100%, respectively, with a specificity of 75%, and 100%. Sensitivity, specificity, positive and negative predictive values of MDCTC for diagnosis of acute and chronic disease were best for chronic disease. Sensitivity was worst for acute ulcerative colitis and specificity was worst for acute Crohn's disease. Haustral loss was seen only in ulcerative colitis. Pseudopolyps and fistulae were findings exclusive to Crohn's disease. Particularly extraintestinal findings as increased vascularization and local lymphadenopathy correlated well with endoscopic definition of acute disease. Because of the possibly more vulnerable colonic wall in acute inflammatory bowel disease, the air inflation for MDCTC should be performed most carefully to avoid any risk of colonic perforation. Conclusion: MDCTC may help to distinguish between patients with acute and chronic IBD. Especially extraintestinal complications, tumorous as well as pseudo-tumorous lesions can be detected with high sensitivity and specificity.

  18. Evaluation of retrospectively ECG-gated 4-row multidetector CT in patients planned for minimal invasive coronary artery bypass grafting

    International Nuclear Information System (INIS)

    Purpose: Minimal invasive direct coronary artery bypass grafting (MIDCAB) or off-pump coronary artery bypass grafting (OPCAB) on the beating heart with full or mini-sternotomy are becoming more common in coronary bypass surgery of the left anterior descending (LAD). In the decision, which surgical approach (MIDCAB, OPCAB or conventional surgery with cardiopulmonary bypass) will be best used, knowledge of the anatomical field is of major importance. The aim of the study was to evaluate retrospective ECG-gated 4-row multidetector CT (MDCT) in patients planned for MIDCAB as additional imaging to coronary angiography. Material and methods: The study included 25 consecutive patients. MSCT was performed as unenhanced (collimation 4 x 2.5 mm) and contrast-enhanced examination (140-170 ml, 300 mg Iodine/ml, collimation 4 x 1 mm). The evaluation included presence of LAD calcifications, distance of LAD and left internal mammarian artery (LIMA), coursek of LAD and LIMA, the presence or absence of bridging through myocardium or epicardial fat and the presence of pleural fibrosis. The MDCT results were correlated with intra-operative findings. Results: All MDCTs could be assessed with reference to the demands. In 20/25 operations, MDCT had direct influence as to the selection of the surgical approach (11 MIDCAB, 7 OPCAB with mini-sternotomy and 5 with full sternotomy, 2 conventional surgeries). The distance of LAD and LIMA varied from 0.9 to 4.5 cm in MDCT. As to calcifications, 3/25 correlated patients had calcifications and 10 patients had no calcifications in the middle LAD. Seven patients had intraoperative fibrosis of the vessel wall without calcification of the middle LAD, which could not be detected with MDCT. Another 5 patients had single calcified plaques in the middle LAD, 4 of these had a fibrosis of the vessel and 1 had a normal vessel at surgery. In these cases, the anastomosis was done between the calcified plaques. No myocardial bridging was detected by MDCT and

  19. A model for quantitative correction of coronary calcium scores on multidetector, dual source, and electron beam computed tomography for influences of linear motion, calcification density, and temporal resolution : A cardiac phantom study

    NARCIS (Netherlands)

    Greuter, M. J. W.; Groen, J. M.; Nicolai, L. J.; Dijkstra, H.; Oudkerk, M.

    2009-01-01

    Purpose: The objective of this study is to quantify the influence of linear motion, calcification density, and temporal resolution on coronary calcium determination using multidetector computed tomography (MDCT), dual source CT (DSCT), and electron beam tomography (EBT) and to find a quantitative me

  20. Multidetector CT imaging of mechanical prosthetic heart valves: quantification of artifacts with a pulsatile in-vitro model

    NARCIS (Netherlands)

    P. Symersky; R.P.J. Budde; P. Westers; B.A.J.M. de Mol; M. Prokop

    2011-01-01

    Multidetector computed tomography (MDCT) can detect the cause of prosthetic heart valve (PHV) dysfunction but is hampered by valve-induced artifacts. We quantified artifacts of four PHV using a pulsatile in-vitro model and assessed the relation to leaflet motion and valve design. A Medtronic Hall ti

  1. Multidetector CT imaging of mechanical prosthetic heart valves : quantification of artifacts with a pulsatile in-vitro model

    NARCIS (Netherlands)

    Symersky, Petr; Budde, Ricardo P. J.; Westers, Paul; de Mol, Bas A. J. M.; Prokop, Mathias

    2011-01-01

    Objectives Multidetector computed tomography (MDCT) can detect the cause of prosthetic heart valve (PHV) dysfunction but is hampered by valve-induced artifacts. We quantified artifacts of four PHV using a pulsatile in-vitro model and assessed the relation to leaflet motion and valve design. Methods

  2. Multidetector CT imaging of mechanical prosthetic heart valves: quantification of artifacts with a pulsatile in-vitro model

    NARCIS (Netherlands)

    Symersky, P.; Budde, R.P.; Westers, P.; Mol, B.A. de; Prokop, M.

    2011-01-01

    OBJECTIVES: Multidetector computed tomography (MDCT) can detect the cause of prosthetic heart valve (PHV) dysfunction but is hampered by valve-induced artifacts. We quantified artifacts of four PHV using a pulsatile in-vitro model and assessed the relation to leaflet motion and valve design. METHODS

  3. Impaired left ventricular function has a detrimental effect on image quality in multi-detector row CT coronary angiography

    International Nuclear Information System (INIS)

    Aim: To determine whether there is a relationship between left ventricular (LV) haemodynamic parameters, circulation times, and arterial contrast opacification that might affect the image quality of computed tomography (CT) coronary angiography. Methods: Thirty-six patients were included in the study: 18 with cardiomyopathy (CM) and LV dilatation of suspected ischaemic aetiology [age 57.9 ± 13.7 years, range 30-77 years; 14 male, four female; body mass index (BMI) = 27.7 ± 4.5, range 25.5-31.8] and 18 controls (age 62.3 ± 9.4 years, range 47-89 years; 10 male, eight female; BMI 27.8 ± 6.6; range 19.2-33.6). Coronary artery image quality was assessed using a three-point visual scale; contrast medium circulation times, aortic root contrast attenuation, and LV functional parameters were studied. Results: Visually reduced contrast opacification impaired image quality more often in the CM group than the control group (27.4 versus 5.1%). A total of 55.6% CM patients had a contrast transit time ranging from 30-75 s; the number of 'unassessable' segments increased with increasing transit time conforming to a fitted quadratic model (R2 = 0.74). The relationship between LV ejection fraction and contrast attenuation may also conform to a quadratic model (R2 = 0.71). Conclusion: LV haemodynamics influence coronary artery opacification using cardiac CT, and users imaging this subgroup must do so with the knowledge of this potential pitfall. The results indicate the need for further studies examining CT protocols in this clinical subgroup

  4. Current Roles and Future Applications of Cardiac CT: Risk Stratification of Coronary Artery Disease

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Yeonyee Elizabeth [Department of Cardiology, Cardiovascular Center, Seoul National University Bundang Hospital, Seongnam 463-707 (Korea, Republic of); Lim, Tae-Hwan [Department of Radiology and Research Institute of Radiology, University of Ulsan College of Medicine, Asan Medical Center, Seoul 138-736 (Korea, Republic of)

    2014-07-01

    Cardiac computed tomography (CT) has emerged as a noninvasive modality for the assessment of coronary artery disease (CAD), and has been rapidly integrated into clinical cares. CT has changed the traditional risk stratification based on clinical risk to image-based identification of patient risk. Cardiac CT, including coronary artery calcium score and coronary CT angiography, can provide prognostic information and is expected to improve risk stratification of CAD. Currently used conventional cardiac CT, provides accurate anatomic information but not functional significance of CAD, and it may not be sufficient to guide treatments such as revascularization. Recently, myocardial CT perfusion imaging, intracoronary luminal attenuation gradient, and CT-derived computed fractional flow reserve were developed to combine anatomical and functional data. Although at present, the diagnostic and prognostic value of these novel technologies needs to be evaluated further, it is expected that all-in-one cardiac CT can guide treatment and improve patient outcomes in the near future.

  5. Current Roles and Future Applications of Cardiac CT: Risk Stratification of Coronary Artery Disease

    International Nuclear Information System (INIS)

    Cardiac computed tomography (CT) has emerged as a noninvasive modality for the assessment of coronary artery disease (CAD), and has been rapidly integrated into clinical cares. CT has changed the traditional risk stratification based on clinical risk to image-based identification of patient risk. Cardiac CT, including coronary artery calcium score and coronary CT angiography, can provide prognostic information and is expected to improve risk stratification of CAD. Currently used conventional cardiac CT, provides accurate anatomic information but not functional significance of CAD, and it may not be sufficient to guide treatments such as revascularization. Recently, myocardial CT perfusion imaging, intracoronary luminal attenuation gradient, and CT-derived computed fractional flow reserve were developed to combine anatomical and functional data. Although at present, the diagnostic and prognostic value of these novel technologies needs to be evaluated further, it is expected that all-in-one cardiac CT can guide treatment and improve patient outcomes in the near future

  6. Wide coverage by volume CT: benefits for cardiac imaging

    Science.gov (United States)

    Sablayrolles, Jean-Louis; Cesmeli, Erdogan; Mintandjian, Laura; Adda, Olivier; Dessalles-Martin, Diane

    2005-04-01

    With the development of new technologies, computed tomography (CT) is becoming a strong candidate for non-invasive imaging based tool for cardiac disease assessment. One of the challenges of cardiac CT is that a typical scan involves a breath hold period consisting of several heartbeats, about 20 sec with scanners having a longitudinal coverage of 2 cm, and causing the image quality (IQ) to be negatively impacted since beat to beat variation is high likely to occur without any medication, e.g. beta blockers. Because of this and the preference for shorter breath hold durations, a CT scanner with a wide coverage without the compromise in the spatial and temporal resolution of great clinical value. In this study, we aimed at determining the optimum scan duration and the delay relative to beginning of breath hold, to achieve high IQ. We acquired EKG data from 91 consecutive patients (77 M, 14 F; Age: 57 +/- 14) undergoing cardiac CT exams with contrast, performed on LightSpeed 16 and LightSpeed Pro16. As an IQ metric, we adopted the standard deviation of "beat-to-beat variation" (stdBBV) within a virtual scan period. Two radiologists evaluated images by assigning a score of 1 (worst) to 4 best). We validated stdBBV with the radiologist scores, which resulted in a population distribution of 9.5, 9.5, 31, and 50% for the score groups 1, 2, 3, and 4, respectively. Based on the scores, we defined a threshold for stdBBV and identified an optimum combination of virtual scan period and a delay. With the assumption that the relationship between the stdBBV and diagnosable scan IQ holds, our analysis suggested that the success rate can be improved to 100% with scan durations equal or less than 5 sec with a delay of 1 - 2 sec. We confirmed the suggested conclusion with LightSpeed VCT (GE Healthcare Technologies, Waukesha, WI), which has a wide longitudinal coverage, fine isotropic spatial resolution, and high temporal resolution, e.g. 40 mm coverage per rotation of 0.35 sec

  7. A technical solution to avoid partial scan artifacts in cardiac MDCT

    OpenAIRE

    Primaka, A. N.; Dong, Y; Dzyubak, O. P.; Jorgensen, S. M.; McCollough, C. H.; Ritman, E.L. (Erik L.)

    2007-01-01

    Quantitative evaluation of cardiac image data obtained using multidetector row computed tomography (CT) is compromised by partial scan reconstructions, which improve the temporal resolution but significantly increase image-to-image CT number variations for a fixed region of interest compared to full reconstruction images. The feasibility of a new approach to solve this problem is assessed. An anthropomorphic cardiac phantom and an anesthetized pig were scanned on a dual-source CT scanner usin...

  8. Imaging pitfalls, normal anatomy, and anatomical variants that can simulate disease on cardiac imaging as demonstrated on multidetector computed tomography

    International Nuclear Information System (INIS)

    Advances in computed tomography have led to continuous improvement in cardiac imaging. Dedicated postprocessing capabilities, faster scan times, and cardiac gating methods reveal details of normal cardiac anatomy and anatomic variants that can mimic pathologic conditions. This article will review normal cardiac anatomy and variants that can mimic disease. Radiologists should be familiar with normal cardiac anatomy and anatomic variants to avoid misinterpretation of normal findings for pathologic processes

  9. Imaging of Herniated Discs of the Cervical Spine: Inter-Modality Differences between 64-Slice Multidetector CT and 1.5-T MRI

    Energy Technology Data Exchange (ETDEWEB)

    Yi, Ji Sook; Cha, Jang Gyu [Dept. of Radiology, Soonchunhyang University Bucheon Hospital, Bucheon (Korea, Republic of); Han, Jong Kyu [Dept. of Radiology, Soonchunhyang University Cheonan Hospital, Cheonan (Korea, Republic of); Kim, Hyun Joo [Dept. of Radiology, Soonchunhyang University Seoul Hospital, Seoul (Korea, Republic of)

    2015-08-15

    To assess inter-modality variability when evaluating cervical intervertebral disc herniation using 64-slice multidetector-row computed tomography (MDCT) and magnetic resonance imaging (MRI). Three musculoskeletal radiologists independently reviewed cervical spine 1.5-T MRI and 64-slice MDCT data on C2-3 though C6-7 of 51 patients in the context of intervertebral disc herniation. Interobserver and inter-modality agreements were expressed as unweighted kappa values. Weighted kappa statistics were used to assess the extents of agreement in terms of the number of involved segments (NIS) in disc herniation and epicenter measurements collected using MDCT and MRI. The interobserver agreement rates upon evaluation of disc morphology by the three radiologists were in fair to moderate agreement (k = 0.39-0.53 for MDCT images; k = 0.45-0.56 for MRIs). When the disc morphology was categorized into two and four grades, the inter-modality agreement rates were moderate (k-value, 0.59) and substantial (k-value, 0.66), respectively. The inter-modality agreements for evaluations of the NIS (k-value, 0.78) and the epicenter (k-value, 0.79) were substantial. Also, the interobserver agreements for the NIS (CT; k-value, 0.85 and MRI; k-value, 0.88) and epicenter (CT; k-value, 0.74 and MRI; k-value, 0.70) evaluations by two readers were substantial. MDCT tended to underestimate the extent of herniated disc lesions compared with MRI. Multidetector-row computed tomography and MRI showed a moderate-to-substantial degree of inter-modality agreement for the assessment of herniated cervical discs. MDCT images have a tendency to underestimate the anterior/posterior extent of the herniated disc compared with MRI.

  10. Automatic coronary calcium scoring in cardiac CT angiography using convolutional neural networks

    NARCIS (Netherlands)

    Wolterink, Jelmer M.; Leiner, Tim; Viergever, Max A.; Isgum, I

    2015-01-01

    The amount of coronary artery calcification (CAC) is a strong and independent predictor of cardiovascular events. Non-contrast enhanced cardiac CT is considered a reference for quantification of CAC. Recently, it has been shown that CAC may be quantified in cardiac CT angiography (CCTA). We present

  11. Detection of blebs and bullae in patients with primary spontaneous pneumothorax by multi-detector CT reconstruction using different slice thicknesses

    International Nuclear Information System (INIS)

    The aim of this study was to compare the diagnostic performances of multi-detector computed tomography (MDCT) reconstruction at two different slice thicknesses (1mm, 'high resolution' vs. 5mm, 'routine') with respect to the detection of blebs and bullae (BBs) in patients with primary spontaneous pneumothorax (PSP). Thirty-one patients underwent wedge resection of BBs (29 unilateral and 2 bilateral) for PSP from January 2010 to January 2013. Two observers assessed the presence and locations of BBs independently using high-resolution CT (HRCT) and routine CT reconstruction, and compared the sensitivities of each reconstruction method for BB detection using operative findings as a standard reference. In addition, the number of BBs in each CT image set was recorded and inter-observer agreements were evaluated. Sensitivity for the detection of BBs was significantly better for HRCT than routine CT (97.0% vs. 63.6% for observer 1 and 94.0% vs. 57.6% for observer 2, respectively, both P-values<0.001). On a per-bleb and a per-bulla basis, inter-observer agreements regarding BBs by HRCT were good and very good (k=0.66 and 0.94, respectively) and superior to those determined by routine CT (k=0.59 and 0.60, respectively). Different slice thickness reconstructions influence the diagnostic efficacy of MDCT for the detection of BBs in patients with PSP. High-resolution thin slice CT reconstruction was found to have a significantly greater sensitivity than routine thicker slice thickness reconstruction for the detection of BBs.

  12. Assessment of coronary artery aneurysms in paediatric patients with Kawasaki disease by multidetector row CT angiography: feasibility and comparison with 2D echocardiography

    International Nuclear Information System (INIS)

    Transthoracic ECHO is the locally accepted method for coronary surveillance of patients with Kawasaki disease but it may have limited visualization in the older child. To assess the feasibility of multidetector CT (MDCT) angiography in the follow-up of coronary artery aneurysms in children with previous Kawasaki disease. Six children (5 boys, 1 girl; mean age 11.5 years) with known Kawasaki disease and coronary artery involvement underwent CT coronary angiography using 16-detector MDCT. The visualized lengths and diameter of all coronary segments were measured. The number, size and location of coronary artery aneurysms were recorded and compared with recent ECHO. Twelve coronary artery aneurysms (seven saccular, five fusiform) were identified by MDCT angiography. One saccular aneurysm at the junction of the distal right coronary artery and posterior descending artery was not detected by ECHO while the remaining six in proximal segments were detected by both modalities. Two of five fusiform aneurysms were not detected by ECHO due to their small sizes. Excellent agreement was found between CT and ECHO for maximal diameter and length of the visualized aneurysms. MDCT angiography accurately defines coronary artery aneurysms. It is more sensitive for detecting aneurysms at distal coronary segments and fusiform aneurysms of small size

  13. Coronal multiplanar reconstruction view from isotropic voxel data sets obtained with multidetector-row CT. Assessment of detection and size of mediastinal and hilar lymph nodes

    International Nuclear Information System (INIS)

    To assess the detection and size of mediastinal and hilar lymph nodes by multiplanar reconstruction (MPR) view from isotropic voxel data sets obtained with multidetector-row computed tomography (MDCT). Thin-section CT of 27 patients with mediastinal or hilar lymph node swelling was obtained with a 25.6-cm field of view (FOV), 512 x 512 matrix, and two protocols: 0.5-mm collimation, 0.3-mm interval (Set A), and 2-mm collimation, 1-mm interval (Set B). MPR views with a 0.5-mm slice thickness were obtained from these two data sets. Postcontrast axial CT used 5-mm collimation (set C). Two observers evaluated the presence and cranio-caudal length of swollen lymph nodes. Two other board-certified chest radiologists evaluated all three sets and established a gold standard by consensus. The accuracy of detection was 76%, 73%, and 68% for sets A, B, and C, respectively. There was a significant difference between sets A and C (McNemar's test: p0.05). The cranio-caudal length of lymph nodes was significantly correlated with the gold standard only in set A (Pearson's correlation coefficient: r=0.53, p<0.05). Non-contrast enhanced coronal MPR views constructed from isotropic voxel data sets may be substituted for axial enhanced CT for the evaluation of mediastinal and hilar lymph nodes. (author)

  14. Radiation Dose to the Thyroid and Gonads in Patients Undergoing Cardiac CT Angiography

    OpenAIRE

    Behroozi, Hamid; Davoodi, Mohammad; Aghasi, Shahriar

    2015-01-01

    Background: The present data show a global increase in the rate of cardiovascular disease. Cardiac CT angiography has developed as a fast and non-invasive cardiac imaging modality following the introduction of multi-slice computed tomogaraphy. Objectives: The aim of this study was to measure the radiation dose to the thyroid and pelvis regions in patients undergoing cardiac CT angiography using the Care Dose 4D method of 64-slice scanner. Patients and Methods: Eighty-one patients (41 males an...

  15. Adult Moyamoya disease: 320-Multidetector row CT for evaluation of revascularization in STA–MCA bypasses surgery

    Energy Technology Data Exchange (ETDEWEB)

    Tian, Bing; Xu, Bing; Liu, Qi; Hao, Qiang; Lu, Jianping, E-mail: cjr.lujianping@vip.163.com

    2013-12-01

    Purpose: To evaluate the utility of 320-multidetector row whole-brain computed tomography perfusion (WBCTP) and whole-head subtracted dynamic angiography (WHSDCTA) for assessing the revascularization of blood flow after superficial temporal artery (STA) to middle cerebral artery (MCA) bypass surgery in adults with Moyamoya disease (MD) in the short and long term. Patients and methods: 320-multidetector row WBCTP and WHSDCTA were applied in 20 patients with MD before and after surgery (for an average of 3 days and 3 months). The bypass arteries were investigated using WHSDCTA and compared with DSA. The regions of interests (ROIs) in the surgical and mirror sides of the cerebral cortex were drawn on a Vitrea Workstation. Cerebral blood volume (CBV), time to peak (TTP), cerebral blood flow (CBF), mean transit time (MTT), and delay time were recorded. Preoperative and postoperative perfusion parameters in the MCA distribution were compared using the paired t-test. Results: WHSDCTA could clearly demonstrate 24 bypass arteries in 26 arteries for 20 patients, results which were in accordance with the results of digital subtraction angiography (DSA). When comparing preoperative values to those within 3 days after surgery, only TTP and delay time were significantly different (P < 0.05). Values of CBV, TTP, CBF, delay time, and MTT 3 months after surgery were significantly different (P < 0.05) from those of preoperative perfusion. Conclusion: These data suggest that 320-multidetector row WBCTP and WHSDCTA can be used to evaluate the revascularization of blood flow after STA–MCA bypass surgery in patients with MD in the short and long term.

  16. Adult Moyamoya disease: 320-Multidetector row CT for evaluation of revascularization in STA–MCA bypasses surgery

    International Nuclear Information System (INIS)

    Purpose: To evaluate the utility of 320-multidetector row whole-brain computed tomography perfusion (WBCTP) and whole-head subtracted dynamic angiography (WHSDCTA) for assessing the revascularization of blood flow after superficial temporal artery (STA) to middle cerebral artery (MCA) bypass surgery in adults with Moyamoya disease (MD) in the short and long term. Patients and methods: 320-multidetector row WBCTP and WHSDCTA were applied in 20 patients with MD before and after surgery (for an average of 3 days and 3 months). The bypass arteries were investigated using WHSDCTA and compared with DSA. The regions of interests (ROIs) in the surgical and mirror sides of the cerebral cortex were drawn on a Vitrea Workstation. Cerebral blood volume (CBV), time to peak (TTP), cerebral blood flow (CBF), mean transit time (MTT), and delay time were recorded. Preoperative and postoperative perfusion parameters in the MCA distribution were compared using the paired t-test. Results: WHSDCTA could clearly demonstrate 24 bypass arteries in 26 arteries for 20 patients, results which were in accordance with the results of digital subtraction angiography (DSA). When comparing preoperative values to those within 3 days after surgery, only TTP and delay time were significantly different (P < 0.05). Values of CBV, TTP, CBF, delay time, and MTT 3 months after surgery were significantly different (P < 0.05) from those of preoperative perfusion. Conclusion: These data suggest that 320-multidetector row WBCTP and WHSDCTA can be used to evaluate the revascularization of blood flow after STA–MCA bypass surgery in patients with MD in the short and long term

  17. Clinical and multidetector CT follow-up results of renal artery aneurysms treated by detachable coil embolization using 3D rotational angiography

    Energy Technology Data Exchange (ETDEWEB)

    Seo, Jung Min; Park, Kwang Bo; Kim, Keon Ha; Jeon, Pyoung; Shin, Sung Wook; Park, Hong Suk; Do, Young Soo (Dept. of Radiology and the Center for Imaging Science, Samsung Medical Center, Sungkyunkwan Univ. School of Medicine, Seoul (Korea, Republic of)), email: kbparksmc@skku.edu; Kim, Dong-Ik; Kim, Young-Wook (Div. of Vascular Surgery, Dept. of Surgery, Samsung Medical Center, Sungkyunkwan Univ. School of Medicine, Seoul (Korea, Republic of))

    2011-10-15

    Background: There are very few reports regarding the use of 3D rotational angiography (3D RA) in embolization of renal artery aneurysms (RAAs). No valuable data have been reported on the follow-up result of coil embolization for RAAs on computed tomography (CT). Purpose: To evaluate the clinical and multidetector computed tomography (MDCT) follow-up results of renal artery aneurysms treated by detachable coil embolization using 3D RA. Material and Methods: Six patients diagnosed with RAAs were included. Five patients underwent detachable coil embolization. Five patients underwent 3D RA and the parameters used for planning endovascular treatment obtained by 2D CT, reformatted 3D CT angiography (3D CTA), 2D digital subtraction angiography (2D DSA) and 3D RA were compared. The post embolization MDCT follow-up findings were analyzed retrospectively. Results: The technical success rate for detachable coil embolization was 40%. The 3D CTA showed the dome-to-neck ratio (DNR) and tangential view of the renal artery aneurysm in five patients (83.3%) and the 2D CT showed it in four (66.7%). An optimal working angle assessment could not be obtained on the 2D CT and 3D CTA. The 3D RA showed the DNR, tangential view, and optimal working angle in all patients. Renal infarction occurred in three patients and Postprocedural hypertension developed in two patients during the follow-up period. Conclusion: The 3D RA was useful in preoperative determination of adequate working angle for detachable coil embolization of RAAs. Late complications of detachable coil embolization for RAAs were renal infarction and hypertension

  18. A cardiac phantom study on quantitative correction of coronary calcium score on multi-detector, dual source, and electron beam tomography for velocity, calcification density, and acquisition time

    Science.gov (United States)

    Greuter, Marcel J. W.; Groen, Jaap M.; Nicolai, Lieuwe J.; Dijkstra, Hildebrand; Oudkerk, Matthijs

    2009-02-01

    Objective: To quantify the influence of velocity, calcification density and acquisition time on coronary calcium determination using multi-detector CT, dual-source CT and EBT. Materials and Methods: Artificial arteries with four calcifications of increasing density were attached to a robotic arm to which a linear movement was applied between 0 and 120 mm/s (step 10 mm/s). The phantom was scanned five times on 64-slice MDCT, DSCT and EBT using a standard acquisition protocol and the average Agatston score was determined. Results: Increasing motion artifacts were observed at increasing velocities on all scanners, with increasing severity from EBT to DSCT to 64-slice MDCT. The Agatston score showed a linear dependency on velocity from which a correction factor was derived. This correction factor showed a linear dependency on calcification density (0.92density of individual calcifications. The dependency of the Agatston score on velocity shows a linear behaviour on calcification density. A quantitative method could be derived which corrects the measured calcium score for the influence of velocity, calcification density and acquisition time.

  19. Quantification of myocardial blood flow using dynamic 320-row multi-detector CT as compared with 15O-H2O PET

    International Nuclear Information System (INIS)

    This study introduces a method to calculate myocardium blood flow (MBF) and coronary flow reserve (CFR) using the relatively low-dose dynamic 320-row multi-detector computed tomography (MDCT), validates the method against 15O-H2O positron-emission tomography (PET) and assesses the CFRs of coronary artery disease (CAD) patients. Thirty-two subjects underwent both dynamic CT perfusion (CTP) and PET perfusion imaging at rest and during pharmacological stress. In 12 normal subjects (pilot group), the calculation method for MBF and CFR was established. In the other 13 normal subjects (validation group), MBF and CFR obtained by dynamic CTP and PET were compared. Finally, the CFRs obtained by dynamic CTP and PET were compared between the validation group and CAD patients (n = 7). Correlation between MBF of MDCT and PET was strong (r = 0.95, P CT in the CAD group (2.3 ± 0.8) was significantly lower than that in the validation group (5.2 ± 1.8) (P = 0.0011). We established a method for measuring MBF and CFR with the relatively low-dose dynamic MDCT. Lower CFR was well demonstrated in CAD patients by dynamic CTP. (orig.)

  20. Quantification of myocardial blood flow using dynamic 320-row multi-detector CT as compared with {sup 15}O-H{sub 2}O PET

    Energy Technology Data Exchange (ETDEWEB)

    Kikuchi, Yasuka; Oyama-Manabe, Noriko; Kudo, Kohsuke [Hokkaido University Hospital, Department of Diagnostic and Interventional Radiology, Sapporo (Japan); Naya, Masanao [Hokkaido University Graduate School of Medicine, Department of Cardiovascular Medicine, Sapporo (Japan); Manabe, Osamu; Tomiyama, Yuuki; Tamaki, Nagara [Hokkaido University Graduate School of Medicine, Department of Nuclear Medicine, Sapporo (Japan); Sasaki, Tsukasa [Hokkaido University Hospital, Department of Radiology, Sapporo (Japan); Katoh, Chietsugu [Hokkaido University Faculty of Health Sciences, Sapporo (Japan); Shirato, Hiroki [Hokkaido University Graduate School of Medicine, Department of Radiation Medicine, Sapporo (Japan)

    2014-07-15

    This study introduces a method to calculate myocardium blood flow (MBF) and coronary flow reserve (CFR) using the relatively low-dose dynamic 320-row multi-detector computed tomography (MDCT), validates the method against {sup 15}O-H{sub 2}O positron-emission tomography (PET) and assesses the CFRs of coronary artery disease (CAD) patients. Thirty-two subjects underwent both dynamic CT perfusion (CTP) and PET perfusion imaging at rest and during pharmacological stress. In 12 normal subjects (pilot group), the calculation method for MBF and CFR was established. In the other 13 normal subjects (validation group), MBF and CFR obtained by dynamic CTP and PET were compared. Finally, the CFRs obtained by dynamic CTP and PET were compared between the validation group and CAD patients (n = 7). Correlation between MBF of MDCT and PET was strong (r = 0.95, P < 0.0001). CFR showed good correlation between dynamic CTP and PET (r = 0.67, P = 0.0126). CFR{sub CT} in the CAD group (2.3 ± 0.8) was significantly lower than that in the validation group (5.2 ± 1.8) (P = 0.0011). We established a method for measuring MBF and CFR with the relatively low-dose dynamic MDCT. Lower CFR was well demonstrated in CAD patients by dynamic CTP. (orig.)

  1. Cardiac computed tomography in patients with acute coronary syndrome; Kardiale CT beim akuten Koronarsyndrom

    Energy Technology Data Exchange (ETDEWEB)

    Schlett, C.L. [Universitaetsklinikum, Heidelberg (Germany). Abt. fuer Diagnostische und Interventionelle Radiologie; Alkadhi, H. [Universitaetsspital, Zuerich (Switzerland); Bamberg, F. [Universitaetsklinikum, Tuebingen (Germany). Diagnostische und Interventionelle Radiologie

    2014-09-15

    Currently, cardiac computed tomography (CT) is increasingly being implemented into clinical algorithms, primarily due to substantial technical advances over the last decade. Its use in the setting of suspected acute coronary syndrome is of particular relevance, given the high degree of accumulating scientific evidence of improving patient outcomes. Performing cardiac CT requires specific knowledge on the available scan acquisitions and patient preparation. Also, expertise is required in order to interpret the coronary and extra-coronary findings adequately. The present article provides an overview of the different aspects on the use of cardiac CT in the setting of acute coronary syndrome.

  2. Multi-detector CT angiography for the assessment of anterior spinal artery and artery of Adamkiewicz patency in patients suspected of having thoracic aortic pathology

    Institute of Scientific and Technical Information of China (English)

    Shaohong ZHAO; Laura Logan; Pamela Schraedley; Geoffrey D.Rubin

    2006-01-01

    Objective To evaluate the visualization of the anterior spinal artery (ASA) and the artery of Adamkiewicz (AKA) as well as the affecting factors for the detection rate using multidetector row CT (MDCT). Methods Ninety-nine consecutive patients (31 women and 68 men; age range, 25-90 years; average age 61.3 years) with suspicion for thoracic aortic lesions necessitating surgical intervention (31 aortic aneurysm, 45 dissection, 5 intramural hematoma, and 18 normal), underwent 16-slice MDCT angiography from the aortic arch to the aortic bifurcation. Transverse sections, multiplanar reformations (MPR) and thin maximum intensity projections (MIP) were used to assess the ASA and AKA. The level of the ASA and AKA origins and CT acquisition parameters were recorded. The contrast-to-noise ratio (CNR) of the image, an index of the mass of the T11 body (vertebral mass index), the subcutaneous fat thickness,and the CT value within the aortic arch and at the T11 level were measured. The detection of the ASA and AKA was evaluated relative to the acquisition parameters, scan characteristics, and aortic lesion type. Differences were assessed with Wilcoxon rank-sum and t tests. Results The ASA was visualized in 51 patients (52%) and the AKA in 18 patients (18 %). The ASA was identified in 36/67 (54%)patients with 1.25 mm thickness and in15/32 (47%) patients with 2.5-3.0 mm thickness. This difference did not achieve significance (P=0.13). The detection rate of the ASA and the AKA was influenced by vertebral mass index and the CNR (P<0.05). The amount of subcutaneous fat affected the detection rate of the ASA (P<0.05) but not the AKA. In CT scans with ASA detection, the mean CT values in the aorta at the arch and at T11 were 360 and 358 HU, respectively; whereas in CT scans without ASA detection, the CT values in the aorta at the arch and at T11 were lower (297 and 317 HU, respectively; both P<0.05). Conclusion The ASA and AKA were less frequently detected in our cohorts than

  3. Evaluation of the relationship between extremity soft tissue sarcomas and adjacent major vessels using contrast-enhanced multidetector CT and three-dimensional volume-rendered CT angiography - A preliminary study

    Energy Technology Data Exchange (ETDEWEB)

    Li, YangKang; Lin, JianBang; Cai, AiQun; Zhou, XiuGuo [Dept. of Radiology, Cancer Hospital, Shantou Univ. Medical College, Guangdong Province (China)], e-mail: yk_li@tom.com; Zheng, Yu [Dept. of Clinical Pharmacology, Cancer Hospital, Shantou Univ. Medical College, Guangdong Province (China); Wei, XiaoLong [Dept. of Pathology, Cancer Hospital, Shantou Univ. Medical College, Guangdong Province (China); Cheng, Ying; Liu, GuoRui [Dept. of Diagnostic Imaging, the Second affiliated Hospital of Shantou Univ. Medical College, Guangdong Province (China)

    2013-10-15

    Background: Accurate description of the relationship between extremity soft tissue sarcoma and the adjacent major vessels is crucial for successful surgery. In addition to magnetic resonance imaging (MRI) or in patients who cannot undergo MRI, two-dimensional (2D) postcontrast computed tomography (CT) images and three-dimensional (3D) volume-rendered CT angiography may be valuable alternative imaging techniques for preoperative evaluation of extremity sarcomas. Purpose: To preoperatively assess extremity sarcomas using multidetector CT (MDCT), with emphasis on postcontrast MDCT images and 3D volume-rendered MDCT angiography in evaluating the relationship between tumors and adjacent major vessels. Material and Methods: MDCT examinations were performed on 13 patients with non-metastatic extremity sarcomas. Conventional CT images and 3D volume-rendered CT angiography were evaluated, with focus on the relationship between tumors and adjacent major vessels. Kappa consistency statistics were performed with surgery serving as the reference standard. Results: The relationship between sarcomas and adjacent vessels was described as one of three patterns: proximity, adhesion, and encasement. Proximity was seen in five cases on postcontrast CT images or in eight cases on volume-rendered images. Adhesion was seen in three cases on both postcontrast CT images and volume-rendered images. Encasement was seen in five cases on postcontrast CT images or in two cases on volume-rendered images. Compared to surgical results, postcontrast CT images had 100% sensitivity, 83.3% specificity, 87.5% positive predictive value, 100% negative predictive value, and 92.3% accuracy in the detection of vascular invasion ({kappa} = 0.843, P = 0.002). 3D volume-rendered CT angiography had 71.4% sensitivity, 100% specificity, 100% positive predictive value, 75% negative predictive value, and 84.6% accuracy in the detection of vascular invasion ({kappa} = 0.698, P = 0.008). On volume-rendered images

  4. Cardiac CT for planning redo cardiac surgery: effect of knowledge-based iterative model reconstruction on image quality

    Energy Technology Data Exchange (ETDEWEB)

    Oda, Seitaro [MedStar Washington Hospital Center, Department of Cardiology, Washington, DC (United States); Kumamoto University, Department of Diagnostic Radiology, Faculty of Life Sciences, Kumamoto (Japan); Weissman, Gaby; Weigold, W. Guy [MedStar Washington Hospital Center, Department of Cardiology, Washington, DC (United States); Vembar, Mani [Philips Healthcare, CT Clinical Science, Cleveland, OH (United States)

    2015-01-15

    The purpose of this study was to investigate the effects of knowledge-based iterative model reconstruction (IMR) on image quality in cardiac CT performed for the planning of redo cardiac surgery by comparing IMR images with images reconstructed with filtered back-projection (FBP) and hybrid iterative reconstruction (HIR). We studied 31 patients (23 men, 8 women; mean age 65.1 ± 16.5 years) referred for redo cardiac surgery who underwent cardiac CT. Paired image sets were created using three types of reconstruction: FBP, HIR, and IMR. Quantitative parameters including CT attenuation, image noise, and contrast-to-noise ratio (CNR) of each cardiovascular structure were calculated. The visual image quality - graininess, streak artefact, margin sharpness of each cardiovascular structure, and overall image quality - was scored on a five-point scale. The mean image noise of FBP, HIR, and IMR images was 58.3 ± 26.7, 36.0 ± 12.5, and 14.2 ± 5.5 HU, respectively; there were significant differences in all comparison combinations among the three methods. The CNR of IMR images was better than that of FBP and HIR images in all evaluated structures. The visual scores were significantly higher for IMR than for the other images in all evaluated parameters. IMR can provide significantly improved qualitative and quantitative image quality at in cardiac CT for planning of reoperative cardiac surgery. (orig.)

  5. Validity of blood flow measurement using 320 multi-detectors CT and first-pass distribution theory: a phantom study

    Science.gov (United States)

    Chen, Jun; Yu, Xuefang; Xu, Shaopeng; Zhou, Kenneth J.

    2015-03-01

    To evaluate the feasibility of measuring the myocardial blood flow using 320 row detector CT by first-pass technique. Heart was simulated with a container that was filled with pipeline of 3mm diameter; coronary artery was simulated with a pipeline of 2 cm diameter and connected with the simulated heart. The simulated coronary artery was connected with a big container with 1500 ml saline and 150ml contrast agent. One pump linking with simulated heart will withdraw with a speed of 10 ml/min, 15 ml/min, 20 ml/min, 25 ml/min and 30 ml/min. First CT scan starts after 30 s of pumpback with certain speed. The second CT scan starts 5 s after first CT scans. CT images processed as follows: The second CT scan images subtract first CT scan images, calculate the increase of CT value of simulated heart and the CT value of the unit volume of simulated coronary artery and then to calculate the total inflow of myocardial blood flow. CT myocardial blood flows were calculated as: 0.94 ml/s, 2.09 ml/s, 2.74 ml/s, 4.18 ml/s, 4.86 ml/s. The correlation coefficient is 0.994 and r2 = 0.97. The method of measuring the myocardial blood flow using 320 row detector CT by 2 scans is feasible. It is possible to develop a new method for quantitatively and functional assessment of myocardial perfusion blood flow with less radiation does.

  6. Highlights of the 12th International Conference on Nuclear Cardiology and Cardiac CT.

    Science.gov (United States)

    Kitsiou, Anastasia; Dorbala, Sharmila; Scholte, Arthur J H A

    2015-09-01

    The 12th International Conference on Nuclear Cardiology and Cardiac CT was held from 3 to 5 May 2015 in Madrid, Spain. In this article, the three Congress Program Committee Chairs summarize selected highlights of the presented abstracts.

  7. "Porcelain heart" cardiomyopathy secondary to hyperparathyroidism: radiographic, echocardiographic, and cardiac CT appearances.

    LENUS (Irish Health Repository)

    Freeman, James

    2010-11-01

    We report the radiographic, echocardiographic and cardiac CT appearances of \\'porcelain heart\\' in an 85-year-old woman who presented with progressive heart failure. The extensive myocardial calcification was secondary to hyperparathyroidism with renal failure.

  8. "Porcelain heart" cardiomyopathy secondary to hyperparathyroidism: radiographic, echocardiographic, and cardiac CT appearances.

    LENUS (Irish Health Repository)

    Freeman, James

    2012-02-01

    We report the radiographic, echocardiographic and cardiac CT appearances of \\'porcelain heart\\' in an 85-year-old woman who presented with progressive heart failure. The extensive myocardial calcification was secondary to hyperparathyroidism with renal failure.

  9. Atresia of the bilateral pulmonary veins: a rare and dismal anomaly identified on cardiac CT

    Energy Technology Data Exchange (ETDEWEB)

    Goo, Hyun Woo; Park, Sang-Hyub; Koo, Hyun Jung; Cho, Young Hoon; Lee, Eunsol [University of Ulsan College of Medicine, Asan Medical Center, Department of Radiology and Research Institute of Radiology, Seoul (Korea, Republic of)

    2014-08-15

    Imaging findings of bilateral pulmonary vein atresia have not been described. To describe cardiac CT findings and clinical outcomes of bilateral pulmonary vein atresia. Three newborns with bilateral pulmonary vein atresia were encountered at our institution during a period of 8 years. We evaluated prenatal echocardiographic findings, clinical presentations, postnatal echocardiographic findings, chest radiographic findings, cardiac CT findings and clinical outcomes. All newborns presented immediately after birth with severe cyanosis, respiratory distress and acidosis that were unresponsive to medical management. Prenatal and postnatal echocardiographic studies and chest radiography were misleading, inconclusive or nonspecific in making the diagnosis in these children; however cardiac CT clearly demonstrated atresia of the bilateral pulmonary veins with multiple small mediastinal collateral veins and pulmonary edema. Surgical treatments were not feasible for this anomaly. Their clinical outcomes were universally dismal and all infants died within 3 days. Cardiac CT provides an accurate diagnosis of bilateral pulmonary vein atresia and leads to prompt treatment decision in these children. (orig.)

  10. Atresia of the bilateral pulmonary veins: a rare and dismal anomaly identified on cardiac CT

    International Nuclear Information System (INIS)

    Imaging findings of bilateral pulmonary vein atresia have not been described. To describe cardiac CT findings and clinical outcomes of bilateral pulmonary vein atresia. Three newborns with bilateral pulmonary vein atresia were encountered at our institution during a period of 8 years. We evaluated prenatal echocardiographic findings, clinical presentations, postnatal echocardiographic findings, chest radiographic findings, cardiac CT findings and clinical outcomes. All newborns presented immediately after birth with severe cyanosis, respiratory distress and acidosis that were unresponsive to medical management. Prenatal and postnatal echocardiographic studies and chest radiography were misleading, inconclusive or nonspecific in making the diagnosis in these children; however cardiac CT clearly demonstrated atresia of the bilateral pulmonary veins with multiple small mediastinal collateral veins and pulmonary edema. Surgical treatments were not feasible for this anomaly. Their clinical outcomes were universally dismal and all infants died within 3 days. Cardiac CT provides an accurate diagnosis of bilateral pulmonary vein atresia and leads to prompt treatment decision in these children. (orig.)

  11. Cardiac CT and cardiac MRI - competitive or complementary for nuclear cardiology; Kardio-CT und Kardio-MR - konkurrierend oder komplementaer zur Nuklearkardiologie?

    Energy Technology Data Exchange (ETDEWEB)

    Moshage, W. [Medizinische Abt. (Kardiologie, Angiologie, Pneumologie, Intensivmedizin), Klinikum Traunstein (Germany)

    2004-09-01

    In summary, cardiac computed tomography (CT) and cardiac magnetic resonance (MR) are two different technologies with distinct imaging properties that gain increasing importance in clinical cardiology. Even though images may look similar, the areas of application of CT and MR are quite different. Clinical applications of cardiac CT focus on on-invasive imaging of the coronary arteries. In this respect, the higher spatial resolution of cardiac CT constitutes a significant advantage as compared to MR and clinical results are superior. Clinical applications of cardiac MR, next to morphologic imaging of the heart, are most frequently found in the context of intra-and pericardial masses, complex congenital anomalies, and the assessment of left ventricular function (dobutamine) and perfusion (adenosine) under stress. The evaluation of the size and localization of myocardial necrosis, scars, and fibrosis gains increasing importance, for example in the workup of myocardial infarction, but also myocarditis and cardiomyopathies. In this respect, magnetic resonance imaging partly constitutes an alternative to nuclear medicine methods. Due to the lack of ionizing radiation and a relatively high spatial resolution, an increase of MR diagnostic procedures at the expense of nuclear medicine can be expected. (orig.)

  12. Intra-individual comparison of patient acceptability of multidetector-row CT colonography and double-contrast barium enema

    International Nuclear Information System (INIS)

    AIMS: To compare the subjective acceptability of CT colonography in comparison with barium enema in older symptomatic patients, and to ascertain preferences for future colonic investigation. MATERIALS AND METHODS: The study population comprised 78 persons aged 60 years or over with symptoms suggestive of colorectal neoplasia, who underwent CT colonography followed the same day by barium enema. A 25-point questionnaire was administered after each procedure and an additional follow-up questionnaire a week later. Responses were compared using Wilcoxon matched pairs testing, Mann-Whitney test statistics and binomial exact testing. RESULTS: Participants suffered less physical discomfort during CT colonography (p=0.03) and overall satisfaction was greater compared with barium enema (p=0.03). On follow-up, respondents reported significantly better tolerance of CT colonography (p=0.002), and were less prepared to undergo barium enema again (p<0.001). Of 52 subjects expressing an opinion, all preferred CT to barium enema. CONCLUSION: Patient satisfaction was higher with CT colonography than barium enema. CT colonography caused significantly less physical discomfort and was overwhelmingly preferred by patients

  13. Monte Carlo simulations to assess the effects of tube current modulation on breast dose for multidetector CT

    OpenAIRE

    Angel, Erin; Yaghmai, Nazanin; Jude, Cecilia Matilda; Demarco, John J.; Cagnon, Christopher H.; Goldin, Jonathan G; Primak, Andrew N.; Stevens, Donna M.; Cody, Dianna D.; McCollough, Cynthia H.; McNitt-Gray, Michael F.

    2009-01-01

    Tube current modulation was designed to reduce radiation dose in CT imaging while maintaining overall image quality. This study aims to develop a method for evaluating the effects of tube current modulation (TCM) on organ dose in CT exams of actual patient anatomy. This method was validated by simulating a TCM and a fixed tube current chest CT exam on 30 voxelized patient models and estimating the radiation dose to each patient’s glandular breast tissue. This new method for estimating organ d...

  14. The effects of emphysema on airway disease: Correlations between multi-detector CT and pulmonary function tests in smokers

    Energy Technology Data Exchange (ETDEWEB)

    Yahaba, Misuzu, E-mail: mis_misuzu@yahoo.co.jp; Kawata, Naoko, E-mail: chumito_03@yahoo.co.jp; Iesato, Ken, E-mail: iesato_k@yahoo.co.jp; Matsuura, Yukiko, E-mail: matsuyuki_future@yahoo.co.jp; Sugiura, Toshihiko, E-mail: sugiura@js3.so-net.ne.jp; Kasai, Hajime, E-mail: daikasai6075@yahoo.co.jp; Sakurai, Yoriko, E-mail: yoliri@nifty.com; Terada, Jiro, E-mail: jirotera@chiba-u.jp; Sakao, Seiichiro, E-mail: sakao@faculty.chiba-u.jp; Tada, Yuji, E-mail: ytada@faculty.chiba-u.jp; Tanabe, Nobuhiro, E-mail: ntanabe@faculty.chiba-u.jp; Tatsumi, Koichiro, E-mail: tatsumi@faculty.chiba-u.jp

    2014-06-15

    Background: Chronic obstructive pulmonary disease (COPD) is characterized by airflow limitation caused by emphysema and small airway narrowing. Quantitative evaluation of airway dimensions by multi-detector computed tomography (MDCT) has revealed a correlation between airway dimension and airflow limitation. However, the effect of emphysema on this correlation is unclear. Objective: The goal of this study was to determine whether emphysematous changes alter the relationships between airflow limitation and airway dimensions as measured by inspiratory and expiratory MDCT. Methods: Ninety-one subjects underwent inspiratory and expiratory MDCT. Images were evaluated for mean airway luminal area (Ai), wall area percentage (WA%) from the third to the fifth generation of three bronchi (B1, B5, B8) in the right lung, and low attenuation volume percent (LAV%). Correlations between each airway index and airflow limitation were determined for each patient and compared between patients with and without evidence of emphysema. Results: In patients without emphysema, Ai and WA% from both the inspiratory and expiratory scans were significantly correlated with FEV{sub 1.} No correlation was detected in patients with emphysema. In addition, emphysematous COPD patients with GOLD stage 1 or 2 disease had significantly lower changes in B8 Ai than non-emphysematous patients. Conclusions: A significant correlation exists between airway parameters and FEV{sub 1} in patients without emphysema. Emphysema may influence airway dimensions even in patients with mild to moderate COPD.

  15. The effects of emphysema on airway disease: Correlations between multi-detector CT and pulmonary function tests in smokers

    International Nuclear Information System (INIS)

    Background: Chronic obstructive pulmonary disease (COPD) is characterized by airflow limitation caused by emphysema and small airway narrowing. Quantitative evaluation of airway dimensions by multi-detector computed tomography (MDCT) has revealed a correlation between airway dimension and airflow limitation. However, the effect of emphysema on this correlation is unclear. Objective: The goal of this study was to determine whether emphysematous changes alter the relationships between airflow limitation and airway dimensions as measured by inspiratory and expiratory MDCT. Methods: Ninety-one subjects underwent inspiratory and expiratory MDCT. Images were evaluated for mean airway luminal area (Ai), wall area percentage (WA%) from the third to the fifth generation of three bronchi (B1, B5, B8) in the right lung, and low attenuation volume percent (LAV%). Correlations between each airway index and airflow limitation were determined for each patient and compared between patients with and without evidence of emphysema. Results: In patients without emphysema, Ai and WA% from both the inspiratory and expiratory scans were significantly correlated with FEV1. No correlation was detected in patients with emphysema. In addition, emphysematous COPD patients with GOLD stage 1 or 2 disease had significantly lower changes in B8 Ai than non-emphysematous patients. Conclusions: A significant correlation exists between airway parameters and FEV1 in patients without emphysema. Emphysema may influence airway dimensions even in patients with mild to moderate COPD

  16. Evaluation of time-related changes in lung detail findings after radiation therapy to the chest using multidetector-row CT. Usefulness of precision scanning

    International Nuclear Information System (INIS)

    Time-related changes in lung detail findings after radiation therapy to the chest were evaluated using multidetector-row CT. The frequency of individual findings and time-related changes in percent incidence of findings were compared between ordinary scanning at 3 mm raw thickness and 8 mm recon thickness, and precision scanning set at 0.5 mm for both parameters. For both scanning methods, the most frequently detected finding was ground-glass opacity (GGO). For all findings other than GGO and consolidation, the frequency of detection was greater with precision scanning than with ordinary scanning. GGO was also the finding showing the greatest difference in frequency of detection between the two scanning methods; because ordinary scanning tended to overvalue GGO, a demonstrative experiment was conducted using a lung detail phantom. Regarding time-related changes in percent incidence of findings, precision scanning was equivalent or superior to ordinary scanning at all time points except after 3 months. These results, combined with the more accurate evaluation of various lung detail changes after radiation therapy to the chest, including GGO (reversible lesion), suggest the usefulness of precision scanning in combination with ordinary scanning. (author)

  17. The role of three-dimensional multidetector CT gastrography in the preoperative imaging of stomach cancer: Emphasis on detection and localization of the tumor

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jin Woong; Shin, Sang Soo; Heo, Suk Hee; Lim, Hyo Soon; Park, Young Kyu; Jeong, Yong Yeon; Kang, Heoung Keun [Chonnam National University Medical School, Gwangju (Korea, Republic of); Lim, Nam Yeol [Dept. of Radiology, Chonnam National University Hospital, Gwangju (Korea, Republic of)

    2015-02-15

    Multidetector CT (MDCT) gastrography has been regarded as a promising technique for the preoperative imaging of gastric cancer. It has the ability to produce various three-dimensional (3D) images. Because 3D reconstruction images are more effective and intuitive for recognizing abnormal changes in the gastric folds and subtle mucosal nodularity than two-dimensional images, 3D MDCT gastrography can enhance the detection rate of early gastric cancer, which, in turn, contributes to the improvement of the accuracy of preoperative tumor (T) staging. In addition, shaded surface display and tissue transition projection images provide a global view of the stomach, with the exact location of gastric cancer, which may replace the need for barium studies. In this article, we discuss technical factors in producing high-quality MDCT gastrographic images and present cases demonstrating the usefulness of MDCT gastrography for the detection and T staging of gastric cancer while emphasizing the significance of preoperative localization of gastric cancer in terms of surgical margin.

  18. Evaluation of living liver donors using contrast enhanced multidetector CT – The radiologists impact on donor selection

    International Nuclear Information System (INIS)

    Living donor liver transplantation (LDLT) is a valuable and legitimate treatment for patients with end-stage liver disease. Computed tomography (CT) has proven to be an important tool in the process of donor evaluation. The purpose of this study was to evaluate the significance of CT in the donor selection process. Between May 1999 and October 2010 170 candidate donors underwent biphasic CT. We retrospectively reviewed the results of the CT and liver volumetry, and assessed reasons for rejection. 89 candidates underwent partial liver resection (52.4%). Based on the results of liver CT and volumetry 22 candidates were excluded as donors (31% of the cases). Reasons included fatty liver (n = 9), vascular anatomical variants (n = 4), incidental finding of hemangioma and focal nodular hyperplasia (n = 1) and small (n = 5) or large for size (n = 5) graft volume. CT based imaging of the liver in combination with dedicated software plays a key role in the process of evaluation of candidates for LDLT. It may account for up to 1/3 of the contraindications for LDLT

  19. Quantitative assessment of first-pass perfusion using a low-dose method at multidetector CT in oesophageal squamous cell carcinoma: Correlation with VEGF expression

    Energy Technology Data Exchange (ETDEWEB)

    Chen, T.-W. [Department of Radiology, West China Hospital of Sichuan University, 37 Guo Xue Xiang, Chengdu, Sichuan 610041 (China) and Sichuan Province Key Laboratory of Medical Imaging and Department of Radiology, Affiliated Hospital of North Sichuan Medical College, 63 Wen Hua Lu, Nanchong, Sichuan 637000 (China); Yang, Z.-G., E-mail: yangzg1117@yahoo.com.cn [Department of Radiology, West China Hospital of Sichuan University, 37 Guo Xue Xiang, Chengdu, Sichuan 610041 (China); State Key Laboratory of Biotherapy, West China Hospital of Sichuan University, 37 Guo Xue Xiang, Chengdu, Sichuan 610041 (China); Chen, H.-J. [Department of Pathology, West China Hospital of Sichuan University, 37 Guo Xue Xiang, Chengdu, Sichuan 610041 (China); Li, Y.; Tang, S.-S.; Yao, J.; Dong, Z.-H. [Department of Radiology, West China Hospital of Sichuan University, 37 Guo Xue Xiang, Chengdu, Sichuan 610041 (China); He, D. [Department of Pathology, West China Hospital of Sichuan University, 37 Guo Xue Xiang, Chengdu, Sichuan 610041 (China)

    2012-08-15

    Aim: To investigate the correlation between vascular endothelial cell growth factor (VEGF) expression and first-pass perfusion parameters at multidetector computed tomography (MDCT) using a low-dose technique, and to determine how to discriminate VEGF positivity from VEGF negativity by perfusion CT in oesophageal squamous cell carcinomas. Materials and methods: Thirty-two patients with oesophageal squamous cell carcinomas underwent first-pass perfusion with 64-section MDCT at 50 mAs. Perfusion parameters, including perfusion, peak enhanced density (PED), time to peak (TTP), and blood volume (BV), were measured. Postoperative specimens were assessed for VEGF expression. Correlation tests were performed to determine the associations between each CT perfusion parameter and VEGF expression. The cut-off values of perfusion parameters were obtained statistically to discriminate VEGF positivity from VEGF negativity. Results: Mean perfusion, PED, TTP, and BV were 38.47 {+-} 30.26 ml/min/ml, 24.68 {+-} 9.65 HU, 28.35 {+-} 9.03 s, and 11.82 {+-} 6.06 ml/100 g, respectively. PED or BV were significantly higher in the VEGF-positive group than in the VEGF-negative group (all p < 0.05), but no significant difference in perfusion or TTP was found between the VEGF-positive and VEGF-negative groups (all p > 0.05). In VEGF positivity, PED and BV were correlated with VEGF expression (r = 0.576 and 0.765, respectively; all p < 0.05), whereas perfusion and TTP were not (r = 0.361 and 0.239, respectively; all p > 0.05). A threshold of BV (10.23 ml/100 g) achieved a sensitivity of 94.4%, and a specificity of 92.9% for discriminating VEGF positivity from VEGF negativity. Conclusion: BV could reflect tumour VEGF expression, and could be an indicator for evaluating angiogenesis in oesophageal tumours.

  20. Multi-detector computed tomography in non-traumatic urologic emergencies; Multidetektor-CT bei nichttraumatischen urologischen Notfaellen

    Energy Technology Data Exchange (ETDEWEB)

    Scherr, M.K. [Ludwig-Maximilians-Universitaet Muenchen (Germany). Institut fuer Klinische Radiologie

    2009-06-15

    Today's modern multi-detector computer tomography (MDCT) with its fast gantry rotation enables scanning of large body volumes with high temporal and spatial resolution. The fast acquisition of data and subsequent data reconstruction enables multiphase protocols with short time gaps between consecutive scan series so that large numbers of scans within one respiratory pause are possible and even in cases of non-cooperative patients acceptable quality of image data is provided. The acquired thin-slice raw data with isotropic submillimeter voxels can be visualized with different reconstruction algorithms. The aadvantages of imaging for diagnostics in urologic emergencies are the excellent visualization of acute arterial and venous pathologies, detailed assessment of renal parenchyma and the precise depiction of the urinary tract. In non-trauma settings this enables detailed visualization of inflammatory diseases and differentiation of obstructive or post-therapeutic pathologies along the upper and lower urinary tract. Based on these MDCT findings adequate therapy planning and planning of interventional or surgical procedures can be carried out. (orig.) [German] Durch den Einsatz moderner Multidetektor-Computertomographen (MDCT) mit schnellen Gantryrotationszeiten sind heute grosse Scanvolumina in hoher zeitlicher und mit hoher raeumlicher Aufloesung moeglich. Die schnelle Bilddatenakquisition und -verarbeitung ermoeglichen Mehrphasenprotokolle mit mehreren kurz aufeinander folgenden Scanserien innerhalb jeweils eines Atemanhalts und eine akzeptable Bildqualitaet bei unkooperativen Patienten. Diese fuehren zu duennschichtigen Rohdaten mit isotropen Voxel im Submillimeterbereich, die mit verschiedenen Nachrekonstruktionsverfahren optimal visualisiert werden koennen. Die urologische Notfalldiagnostik profitiert hier von der hervorragenden Darstellbarkeit akuter Gefaesspathologien in der arteriellen und venoesen Vaskularisation der Nieren. Die renale

  1. Regenerative nodules in patients with chronic Budd-Chiari syndrome: A longitudinal study using multiphase contrast-enhanced multidetector CT

    Energy Technology Data Exchange (ETDEWEB)

    Flor, Nicola [Unita Operativa di Radiologia Diagnostica Interventistica, University of Milan School of Medicine, Ospedale San Paolo, Milan (Italy)], E-mail: flornic@hotmail.com; Zuin, Massimo [Unita Operativa di Epatologia e Gastroenterologia Medica, University of Milan School of Medicine, Ospedale San Paolo, Via A. di Rudini 8, 20142 Milan (Italy); Brovelli, Francesca [Department of Radiology, Centro Diagnostico Italiano, Milan (Italy); Maggioni, Marco [Servizio di Anatomia Patologica, Ospedale San Paolo, Milan (Italy); Tentori, Augusta [Servizio di Radiologia, Ospedale di Voghera (Italy); Sardanelli, Francesco [Radiology, IRCCS Policlinico San Donato, University of Milan School of Medicine, Milan (Italy); Cornalba, Gian Paolo [Unita Operativa di Radiologia Diagnostica Interventistica, University of Milan School of Medicine, Ospedale San Paolo, Milan (Italy)

    2010-03-15

    Objective: Our aim was to evaluate the serial evolution of regenerative nodules in patients with Budd-Chiari syndrome (BCS) treated with portal-systemic shunts, using multiphasic multidetector computed tomography (MDCT). Materials and methods: Five patients each underwent three MDCT exams over an extended period ranging from 36 to 42 months. Two radiologists in consensus retrospectively reviewed each exam for each patient. Individual nodules were grouped according to size (size I: nodules with diameter {<=}15 mm; size II: >15 mm but <30 mm; size III: {>=}30 mm), pattern of enhancement (A: homogeneously hypervascular or B: with central scar), and segmental location. Four nodules classified as size II, which increased in size over time, were needle-biopsied. Results: We detected 61 nodules at the first exam, 66 nodules at the second exam (7 nodules disappeared and 12 new nodules), and 85 nodules at the third exam (8 disappeared and 27 new) for a total of 212 findings. Nodules were mostly found in the right hepatic lobe. Fourteen of the 15 nodules that disappeared over time were size I and enhancement pattern A. At unenhanced MDCT, 204 (96%) of the 212 findings were isodense. Overall, 100 nodules, including the 61 initially detected, were considered newly diagnosed; of these 84 (84%) were size I and pattern A. Of 57 nodules considered size I and pattern A at the first or second exam, 24 (42%) changed to pattern B at the third exam and either size II (n = 18) or III (n = 6). The four biopsied nodules were each confirmed as benign regenerative nodule. No patient developed HCC at 5-year follow-up period. Conclusion: Hepatic nodules in BCS patients not only increase in number over time but may also increase in size and develop a central scar.

  2. Usefulness of multi-detector CT in boyd-Griffin type 2 intertrochanteric fractures with clinical correlation

    Energy Technology Data Exchange (ETDEWEB)

    Han, Suk-Ku; Choi, Nam-Yong [College of Medicine, Catholic University of Korea, Department of Orthopaedic Surgery, St. Paul' s Hospital, Seoul (Korea); Lee, Bae-Young; Kim, Yong-Sik [College of Medicine, Catholic University of Korea, Department of Radiology, St. Paul' s Hospital, Seoul (Korea)

    2010-06-15

    To investigate the usefulness of multi-detector computed tomography (MDCT) in three-part intertrochanteric fractures of proximal femur. Twenty-six patients with Boyd-Griffin type 2 intertrochanteric fractures with MDCT (group 1) and 36 patients of the same type fracture without MDCT (group 2) were compared. Lesser trochanter (LT)/greater trochanter (GT) volume ratio above 0.5 or the volumetric proportion of GT in total volume of proximal femur below 25% was considered an unstable fracture. The fractures were fixed with dynamic compression hip screws (DCS). Additional greater trochanter stabilizing (GTS) plate or bone cement augmentation of the femoral head was performed in unstable fractures. Clinical outcome between the two groups by fixation failure and radiological results was compared. The volume ratio of the LT/GT was 0.33 (range, 0.13-0.73). The volume of the LT was inversely correlated with that of the GT (p < 0.001). The volume of the GT was significantly correlated with the LT/GT ratio or the head and neck (HN)/GT ratio (p < 0.001). Seven cases were regarded as unstable fractures in group 1. Fixation failures happened in one case in group 1 and five cases in group 2. There was significantly lower failure rate in group 1 than group 2 (p=0.03). Neck-shaft angle at last follow-up was 134.8 {+-} 5.3 in group 1 and 131.3 {+-} 5.1 in group 2 (p = 0.01). The sliding length of lag screws were 5.6 {+-} 2.9 mm in group 1 and 8.3 {+-} 3.2 in group 2 (p=0.03). Preoperative use of MDCT provides useful information about the fracture pattern and the geometry of the proximal femur in unstable intertrochanteric fractures and helps surgical planning. The ratio of the LT to the GT is inversely correlated with fracture stability. (orig.)

  3. Regenerative nodules in patients with chronic Budd-Chiari syndrome: A longitudinal study using multiphase contrast-enhanced multidetector CT

    International Nuclear Information System (INIS)

    Objective: Our aim was to evaluate the serial evolution of regenerative nodules in patients with Budd-Chiari syndrome (BCS) treated with portal-systemic shunts, using multiphasic multidetector computed tomography (MDCT). Materials and methods: Five patients each underwent three MDCT exams over an extended period ranging from 36 to 42 months. Two radiologists in consensus retrospectively reviewed each exam for each patient. Individual nodules were grouped according to size (size I: nodules with diameter ≤15 mm; size II: >15 mm but <30 mm; size III: ≥30 mm), pattern of enhancement (A: homogeneously hypervascular or B: with central scar), and segmental location. Four nodules classified as size II, which increased in size over time, were needle-biopsied. Results: We detected 61 nodules at the first exam, 66 nodules at the second exam (7 nodules disappeared and 12 new nodules), and 85 nodules at the third exam (8 disappeared and 27 new) for a total of 212 findings. Nodules were mostly found in the right hepatic lobe. Fourteen of the 15 nodules that disappeared over time were size I and enhancement pattern A. At unenhanced MDCT, 204 (96%) of the 212 findings were isodense. Overall, 100 nodules, including the 61 initially detected, were considered newly diagnosed; of these 84 (84%) were size I and pattern A. Of 57 nodules considered size I and pattern A at the first or second exam, 24 (42%) changed to pattern B at the third exam and either size II (n = 18) or III (n = 6). The four biopsied nodules were each confirmed as benign regenerative nodule. No patient developed HCC at 5-year follow-up period. Conclusion: Hepatic nodules in BCS patients not only increase in number over time but may also increase in size and develop a central scar.

  4. Evaluation of image quality and spatial resolution of low-dose high-pitch multidetector-row helical high-resolution CT in 11 autopsy lungs and a wire phantom

    International Nuclear Information System (INIS)

    The aim of this study was to evaluate whether low-dose high-pitch (6:1) multidetector-row helical high-resolution CT is appropriate for the evaluation of various pulmonary abnormalities, including faint opacities. Eleven autopsy lungs were scanned with a multidetector-row CT scanner using 2.5 mm x 4 beam collimation, effective slice thickness 3 mm, 6:1 pitch, 0.8 second gantry rotation speed, 20 cm Display Fov, high spatial frequency (bone) algorithm, and various radiation doses (120 kVp; 160, 80, 40, 24, and 8 mAs). The image quality of each CT set was assessed as adequate or inadequate for diagnosis by two independent observers. In addition, a wire phantom was scanned with the same parameters in order to describe the modular transfer function (MTF) curves. There was excellent agreement between the observers for the evaluation of image quality (kappa statistic, 0.84). The ratio of images evaluated as inadequate for 8 mAs and 24 mAs was significantly higher than that for 160, 80, and 40 mAs (p<0.01: chi-square test). MTF curves of both 8 and 24 mAs were significantly inferior to those of 40, 80, and 160 mAs (p<0.01, Friedman test), while the MTF curve of 40 mAs was relatively inferior to that of 160 mAs (p<0.05, Friedman test). More than 40 mAs in combination with 120 kVp is preferable for the evaluation of details of lung parenchyma by high-pitch. multidetector-row helical high-resolution CT. (author)

  5. Evaluation of image quality and spatial resolution of low-dose high-pitch multidetector-row helical high-resolution CT in 11 autopsy lungs and a wire phantom

    Energy Technology Data Exchange (ETDEWEB)

    Johkoh, Takeshi; Honda, Osamu; Yamamoto, Shuji [Osaka Univ., Suita (Japan). Medical School] (and others)

    2001-12-01

    The aim of this study was to evaluate whether low-dose high-pitch (6:1) multidetector-row helical high-resolution CT is appropriate for the evaluation of various pulmonary abnormalities, including faint opacities. Eleven autopsy lungs were scanned with a multidetector-row CT scanner using 2.5 mm x 4 beam collimation, effective slice thickness 3 mm, 6:1 pitch, 0.8 second gantry rotation speed, 20 cm Display Fov, high spatial frequency (bone) algorithm, and various radiation doses (120 kVp; 160, 80, 40, 24, and 8 mAs). The image quality of each CT set was assessed as adequate or inadequate for diagnosis by two independent observers. In addition, a wire phantom was scanned with the same parameters in order to describe the modular transfer function (MTF) curves. There was excellent agreement between the observers for the evaluation of image quality (kappa statistic, 0.84). The ratio of images evaluated as inadequate for 8 mAs and 24 mAs was significantly higher than that for 160, 80, and 40 mAs (p<0.01: chi-square test). MTF curves of both 8 and 24 mAs were significantly inferior to those of 40, 80, and 160 mAs (p<0.01, Friedman test), while the MTF curve of 40 mAs was relatively inferior to that of 160 mAs (p<0.05, Friedman test). More than 40 mAs in combination with 120 kVp is preferable for the evaluation of details of lung parenchyma by high-pitch. multidetector-row helical high-resolution CT. (author)

  6. Churg-Strauss Syndrome with Cardiac Involvement: A Case Report with CT and MRI Findings

    Energy Technology Data Exchange (ETDEWEB)

    Lim, Seong Joo; Cho, Young Jun; Kim, Keum; Hwang, Cheol Mok; Kim, Dae Ho [Dept. of Radiology, Konyang University College of Medicine, Daegu (Korea, Republic of); Choi, Eu Gene [Dept. of Internal Medicine, Konyang University College of Medicine, Daegu (Korea, Republic of)

    2012-02-15

    This is a case report of Churg-Strauss Syndrome (CSS) associated with cardiac involvement which is demonstrated in chest CT and cardiac MRI (CMR) without specific cardiac symptoms. A 32-year-old woman had a 3-year history of bronchial asthma, chronic sinusitis, and otitis media. The patient had various typical findings of CSS. The patient had no specific cardiac symptoms or signs such as chest pain, palpitations, syncope, or murmur, but she had diffuse low attenuation lesions in the inner wall of the left ventricle (LV) in contrast-enhanced CT. This corresponded to the area of subendocardial hyperenhancement in delayed contrast-enhanced CMR images. She was treated with steroids for 2 months. Follow-up delayed contrast-enhanced CMR of the LV showed a decrease in the size of the subendocardial enhancement area, and she had no symptoms. Therefore, the radiologist and clinician both should pay careful attention to observe possible cardiac involvement in case of CSS.

  7. Assessment of left ventricular ejection fraction: comparison of two dimensional echocardiography, cardiac magnetic resonance imaging and 64-row multi-detector computed tomography

    Institute of Scientific and Technical Information of China (English)

    Chee Khoon LIEW; Kui Hian SIM; Rapaee ANNUAR; Tiong Kiam ONG; Sze Piaw CHIN; Tobias Seyfarth; Yean Yip FONG; Wei Ling CHAN; Choon Kiat ANG; Houng Bang LIEW

    2006-01-01

    Objectives To compare left ventricular ejection fraction (LVEF) determined from 64-row multi-detector computed tomography (64-row MDCT) with those determined from two dimensional echocardiography (2D echo) and cardiac magnetic resonance imaging (CMR). Methods Thirty-two patients with coronary artery disease underwent trans-thoracic 2D echo, CMR and contrast-enhanced 64-row MDCT for assessment of LVEF within 48 hours of each other. 64-row MDCT LVEF was derived using the Syngo Circulation software; CMR LVEF was by Area Length Ejection Fraction (ALEF) and Simpson method and 2D echo LVEF by Simpson method.Results The LVEF was 49.13 ± 15.91% by 2D echo, 50.72 ± 16.55% (ALEF method) and 47.65 ± 16.58%(Simpson method) by CMR and 50.00 ± 15.93% by 64-row MDCT. LVEF measurements by 64-row MDCT correlated well with LVEF measured with CMR using either the ALEF method (Pearson correlation r = 0.94, P <0.01) or Simpson method (r = 0.92, P<0.01). It also correlated well with LVEF measured using 2D echo (r = 0.80, P < 0.01). Conclusion LVEF measurements by 64-row MDCT correlated well with LVEF measured by CMR and 2D echo. The correlation between 64-row MDCT and CMR was better than the correlation between 2D echo with CMR. Standard data set from a 64-row MDCT coronary study can be reliably used to calculate the LVEF.

  8. Radiation protection in newer medical imaging techniques: Cardiac CT

    International Nuclear Information System (INIS)

    Medical imaging has seen many developments as it has evolved since the mid-1890s. In the last 30-40 years, the pace of innovation has increased, starting with the introduction of computed tomography (CT) in the early 1970s. During the last decade, the rate of change has accelerated further, in terms of continuing innovation and its global application. Most patient exposure now arises from practices that barely existed two decades ago. These developments are evident in the technology on which this volume is based - multislice/detector CT scanning and its application in cardiac imaging. However, this advance is achieved at the cost of a radiation burden to the individual patient, and possibly to the community, if its screening potential is exploited. Much effort will be required to ensure that the undoubted benefit of this new practice will not pose an undue level of detriment to the individual in multiple examinations. For practitioners and regulators, it is evident that innovation has been driven by both the imaging industry and an increasing array of new applications generated and validated in the clinical environment. Regulation, industrial standardization, safety procedures and advice on best practices lag (inevitably) behind the industrial and clinical innovations. This series of Safety Reports (Nos 58, 60 and 61) is designed to help fill this growing vacuum, by bringing up to date and timely advice from experienced practitioners to bear on the problems involved. The advice in this report has been developed as part of the IAEA's statutory responsibility to establish standards for the protection of people against exposure to ionizing radiation and to provide for the worldwide application of these standards. The Fundamental Safety Principles and the International Basic Safety Standards for Protection against Ionizing Radiation and for the Safety of Radiation Sources (BSS) were issued by the IAEA and co-sponsored by organizations including the Food and Agriculture

  9. Multidetector spiral CT arthrography of the shoulder. Clinical applications and limits, with MR arthrography and arthroscopic correlations.

    Science.gov (United States)

    Lecouvet, Frédéric E; Simoni, Paolo; Koutaïssoff, Sophie; Vande Berg, Bruno C; Malghem, Jacques; Dubuc, Jean-Emile

    2008-10-01

    Although MR imaging and MR arthrography are the first choice modalities for shoulder imaging, CT arthrography (CTA) may be used successfully to address many clinical questions. The advent of submillimeter multiple detector CT technology and subsequent excellent three-plane resolution has considerably increased the quality of CTA examinations and has propelled this technique to the forefront in a growing number of indications. The combined use of iodinated contrast material for fluoroscopic confirmation of the articular position of the needle before injection of gadolinium chelates for MR arthrography offers the unique opportunity to compare CTA and MRA findings in carefully selected cases. This paper illustrates capabilities and limits of CTA for the study of rotator cuff tears, shoulder instability, cartilage lesions, anatomical variants and abnormalities of the glenoid labrum, with correlations to MR arthrography and surgical findings.

  10. Detection of hepatocelluar carcinoma on triple-phase images of liver using multi-detector row helical CT

    International Nuclear Information System (INIS)

    To determine whether triple-phase multi-detector-row helical CT images of liver improves the detection rate of hepatocellular carcinoma (HCC). Forty-one patients with 103 HCCs underwent triple-detector-row helical CT imaging of the entire liver after contrast administration. Early and late arterial phase images were obtained serially during a single breath-hold, and portal venous-phase images were then obtained. Each image set was independently assessed for the presence of HCC by two radiologists unaware of the possible presence of tumors, and for each phase the detection rate was determined. For each arterial-phase image, lesion conspicuity (attenuation of a tumor compared with that of its parenchyma) was calculated. For reader 1, the detection rates for the early arterial, late arterial, and portal venous phase were 81%, 77%, and 55%, respectively, and for reader 2 were 83%, 81% and 68%, respectively (p>0.05). When triple-phase imaging findings were combined, the detection rate was significantly higher than when only those of the early or late arterial, and portal venous, phase were used (p0.05). Triple-phase imaging of the liver, involving the early arterial, late arterial, and portal venous phase, and using multi-detector-row helical CT, increases the detection rate of HCC

  11. A method to analyse observer disagreement in visual grading studies: example of assessed image quality in paediatric cerebral multidetector CT images.

    Science.gov (United States)

    Ledenius, K; Svensson, E; Stålhammar, F; Wiklund, L-M; Thilander-Klang, A

    2010-07-01

    The purpose was to demonstrate a non-parametric statistical method that can identify and explain the components of observer disagreement in terms of systematic disagreement as well as additional individual variability, in visual grading studies. As an example, the method was applied to a study where the effect of reduced tube current on diagnostic image quality in paediatric cerebral multidetector CT (MDCT) images was investigated. Quantum noise, representing dose reductions equivalent to steps of 20 mA, was artificially added to the raw data of 25 retrospectively selected paediatric cerebral MDCT examinations. Three radiologists, blindly and randomly, assessed the resulting images from two different levels of the brain with regard to the reproduction of high- and low-contrast structures and overall image quality. Images from three patients were assessed twice for the analysis of intra-observer disagreement. The intra-observer disagreement in test-retest assessments could mainly be explained by a systematic change towards lower image quality the second time the image was reviewed. The inter-observer comparisons showed that the paediatric radiologist was more critical of the overall image quality, while the neuroradiologists were more critical of the reproduction of the basal ganglia. Differences between the radiologists regarding the extent to which they used the whole classification scale were also found. The statistical method used was able to identify and separately measure a presence of bias apart from additional individual variability within and between the radiologists which is, at the time of writing, not attainable by any other statistical approach suitable for paired, ordinal data.

  12. Impact of iterative reconstruction on image quality and radiation dose in multidetector CT of large body size adults

    International Nuclear Information System (INIS)

    To compare image quality and radiation dose using Adaptive Statistical Iterative Reconstruction (ASiR) and Filtered Back Projection (FBP) in patients weighing ≥91 kg. In this Institution Review Board-approved retrospective study, single-phase contrast-enhanced abdominopelvic CT examinations of 100 adults weighing ≥91 kg (mean body weight: 107.6 ± 17.4 kg range: 91-181.9 kg) with (1) ASiR and (2) FBP were reviewed by two readers in a blinded fashion for subjective measures of image quality (using a subjective standardized numerical scale and objective noise) and for radiation exposure. Imaging parameters and radiation dose results of the two techniques were compared within weight and BMI sub-categories. All examinations were found to be of adequate quality. Both subjective (mean = 1.4 ± 0.5 vs. 1.6 ± 0.6, P < 0.05) and objective noise (13.0 ± 3.2 vs.19.5 ± 5.7, P < 0.0001) were lower with ASiR. Average radiation dose reduction of 31.5 % was achieved using ASiR (mean CTDIvol. ASiR: 13.5 ± 7.3 mGy; FBP: 19.7 ± 9.0 mGy, P < 0.0001). Other measures of image quality were comparable between the two techniques. Trends for all parameters were similar in patients across weight and BMI sub-categories. In obese individuals, abdominal CT images reconstructed using ASiR provide diagnostic images with reduced image noise at lower radiation dose. circle CT images in obese adults are noisy, even with high radiation dose. (orig.)

  13. Low-dose interpolated average CT for attenuation correction in cardiac PET/CT

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Tung-Hsin [Department of Biomedical Imaging and Radiological Sciences, National Yang Ming University, Taiwan (China); Zhang, Geoffrey [Department of Radiation Oncology, Moffitt Cancer Center, Florida (United States); Wang, Shyh-Jen [Department of Biomedical Imaging and Radiological Sciences, National Yang Ming University, Taiwan (China); Department of Nuclear Medicine, Taipei Veterans General Hospital, Taiwan (China); Chen, Chih-Hao [Department of Nuclear Medicine, Taipei Veterans General Hospital, Taiwan (China); Yang, Bang-Hung [Department of Biomedical Imaging and Radiological Sciences, National Yang Ming University, Taiwan (China); Department of Nuclear Medicine, Taipei Veterans General Hospital, Taiwan (China); Wu, Nien-Yun [Department of Nuclear Medicine, Taipei Veterans General Hospital, Taiwan (China); Huang, Tzung-Chi, E-mail: tzungchi.huang@mail.cmu.edu.t [Department of Biomedical Imaging and Radiological Science, China Medical University, Taiwan (China)

    2010-07-21

    Because of the advantages in the use of high photon flux and thus the short scan times of CT imaging, the traditional {sup 68}Ge scans for positron emission tomography (PET) image attenuation correction have been replaced by CT scans in the modern PET/CT technology. The combination of fast CT scan and slow PET scan often causes image misalignment between the PET and CT images due to respiration motion. Use of the average CT derived from cine CT images is reported to reduce such misalignment. However, the radiation dose to patients is higher with cine CT scans. This study introduces a method that uses breath-hold CT images and their interpolations to generate the average CT for PET image attenuation correction. Breath-hold CT sets are taken at end-inspiration and end-expiration. Deformable image registration is applied to generate a voxel-to-voxel motion matrix between the two CT sets. The motion is equally divided into 5 steps from inspiration to expiration and 5 steps from expiration to inspiration, generating a total of 8 phases of interpolated CT sets. An average CT image is generated from all the 10 phase CT images, including original inhale/exhale CT and 8 interpolated CT sets. Quantitative comparison shows that the reduction of image misalignment artifacts using the average CT from the interpolation technique for PET attenuation correction is at a similar level as that using cine average CT, while the dose to the patient from the CT scans is reduced significantly. The interpolated average CT method hence provides a low dose alternative to cine CT scans for PET attenuation correction.

  14. Low-dose interpolated average CT for attenuation correction in cardiac PET/CT

    International Nuclear Information System (INIS)

    Because of the advantages in the use of high photon flux and thus the short scan times of CT imaging, the traditional 68Ge scans for positron emission tomography (PET) image attenuation correction have been replaced by CT scans in the modern PET/CT technology. The combination of fast CT scan and slow PET scan often causes image misalignment between the PET and CT images due to respiration motion. Use of the average CT derived from cine CT images is reported to reduce such misalignment. However, the radiation dose to patients is higher with cine CT scans. This study introduces a method that uses breath-hold CT images and their interpolations to generate the average CT for PET image attenuation correction. Breath-hold CT sets are taken at end-inspiration and end-expiration. Deformable image registration is applied to generate a voxel-to-voxel motion matrix between the two CT sets. The motion is equally divided into 5 steps from inspiration to expiration and 5 steps from expiration to inspiration, generating a total of 8 phases of interpolated CT sets. An average CT image is generated from all the 10 phase CT images, including original inhale/exhale CT and 8 interpolated CT sets. Quantitative comparison shows that the reduction of image misalignment artifacts using the average CT from the interpolation technique for PET attenuation correction is at a similar level as that using cine average CT, while the dose to the patient from the CT scans is reduced significantly. The interpolated average CT method hence provides a low dose alternative to cine CT scans for PET attenuation correction.

  15. Low-dose interpolated average CT for attenuation correction in cardiac PET/CT

    Science.gov (United States)

    Wu, Tung-Hsin; Zhang, Geoffrey; Wang, Shyh-Jen; Chen, Chih-Hao; Yang, Bang-Hung; Wu, Nien-Yun; Huang, Tzung-Chi

    2010-07-01

    Because of the advantages in the use of high photon flux and thus the short scan times of CT imaging, the traditional 68Ge scans for positron emission tomography (PET) image attenuation correction have been replaced by CT scans in the modern PET/CT technology. The combination of fast CT scan and slow PET scan often causes image misalignment between the PET and CT images due to respiration motion. Use of the average CT derived from cine CT images is reported to reduce such misalignment. However, the radiation dose to patients is higher with cine CT scans. This study introduces a method that uses breath-hold CT images and their interpolations to generate the average CT for PET image attenuation correction. Breath-hold CT sets are taken at end-inspiration and end-expiration. Deformable image registration is applied to generate a voxel-to-voxel motion matrix between the two CT sets. The motion is equally divided into 5 steps from inspiration to expiration and 5 steps from expiration to inspiration, generating a total of 8 phases of interpolated CT sets. An average CT image is generated from all the 10 phase CT images, including original inhale/exhale CT and 8 interpolated CT sets. Quantitative comparison shows that the reduction of image misalignment artifacts using the average CT from the interpolation technique for PET attenuation correction is at a similar level as that using cine average CT, while the dose to the patient from the CT scans is reduced significantly. The interpolated average CT method hence provides a low dose alternative to cine CT scans for PET attenuation correction.

  16. Three-dimensional fracture visualisation of multidetector CT of the skull base in trauma patients: comparison of three reconstruction algorithms

    International Nuclear Information System (INIS)

    The purpose of this study was to retrospectively assess the detection rate of skull-base fractures for three different three-dimensional (3D) reconstruction methods of cranial CT examinations in trauma patients. A total of 130 cranial CT examinations of patients with previous head trauma were subjected to 3D reconstruction of the skull base, using solid (SVR) and transparent (TVR) volume-rendering technique and maximum intensity projection (MIP). Three radiologists independently evaluated all reconstructions as well as standard high-resolution multiplanar reformations (HR-MPRs). Mean fracture detection rates for all readers reading rotating reconstructions were 39, 36, 61 and 64% for SVR, TVR, MIP and HR-MPR respectively. Although not significantly different from HR-MPR with respect to sensitivity (P = 0.9), MIP visualised 18% of fractures that were not reported in HR-MPR. Because of the relatively low detection rate using HR-MPRs alone, we recommend reading MIP reconstructions in addition to the obligatory HR-MPRs to improve fracture detection. (orig.)

  17. Coronary artery anomalies: Assessment with electrocardiography-gate multidetector-row CT at a single center in Korea

    Energy Technology Data Exchange (ETDEWEB)

    Yi, Bo Ram; Sun, Joo Sung; Yang, Hyoung Mo; Kang, Doo Kyoung [Ajou University School of Medicine, Suwon (Korea, Republic of)

    2015-04-15

    To determine the prevalence of coronary anomalies using coronary computed tomography angiography (CCTA) and to evaluate the relationship between coronary artery anomalies and chest pain. A total of 12676 patients underwent CCTA scans at our institution between December 2006 and April 2013 using a 64-slice CT and a 128-slice dual-source CT. We determined the prevalence of coronary artery anomalies according to the classification system proposed by Greenberg. The presence or absence of chest pain with each coronary artery anomaly was also evaluated. Coronary anomalies were found in 176 patients (1.39%) at our institute. Anomalies of origination, course, and termination were detected in 118 (0.93%), 28 (0.22%), and 30 (0.24%) patients, respectively. After the exclusion of 32 patients with combined heart disease, typical (n = 16; 11.1%) or atypical (n = 28; 19.4%) chest pain was present in 44 (30.6%) of the 144 patients at the time of diagnosis. The prevalence of coronary artery anomalies was 1.39% at our hospital. After the exclusion of patients with combined heart disease, 11.1% had typical chest pain at the time of diagnosis.

  18. Hybrid cardiac imaging: SPECT/CT and PET/CT. A joint position statement by the European Association of Nuclear Medicine (EANM), the European Society of Cardiac Radiology (ESCR) and the European Council of Nuclear Cardiology (ECNC)

    DEFF Research Database (Denmark)

    Flotats, Albert; Gutberlet, Matthias; Knuuti, Juhani;

    2011-01-01

    . The European Association of Nuclear Medicine (EANM), the European Society of Cardiac Radiology (ESCR) and the European Council of Nuclear Cardiology (ECNC) in this paper want to present a position statement of the institutions on the current roles of SPECT/CT and PET/CT hybrid cardiac imaging in patients...

  19. Combined motion estimation and motion-compensated FBP for cardiac CT

    International Nuclear Information System (INIS)

    The image quality in cardiac computed tomography (CT) is still limited by motion artifacts due to insufficient temporal resolution of even the fastest commercially available scanners. At the same time, current protocols for retrospectively gated cardiac CT expose patients to a relatively large radiation dose. Motion-compensated image reconstruction has the potential to solve these problems. We present a 4D approach (3D + time) that first estimates cardiac motion from reconstructed 3D images and then incorporates 4D motion information into an FDK-type image reconstruction algorithm with motion tracking. We observe increased sharpness of clinically relevant anatomical landmarks such as coronary arteries. Additionally, the ability of motion-compensated reconstruction to improve the effective temporal resolution allows to increase the cardiac gating window, using a projection data range significantly larger than that of the typical short-scan. By utilizing more of the available data, the image noise can be reduced. (orig.)

  20. Calibration free beam hardening correction for cardiac CT perfusion imaging

    Science.gov (United States)

    Levi, Jacob; Fahmi, Rachid; Eck, Brendan L.; Fares, Anas; Wu, Hao; Vembar, Mani; Dhanantwari, Amar; Bezerra, Hiram G.; Wilson, David L.

    2016-03-01

    Myocardial perfusion imaging using CT (MPI-CT) and coronary CTA have the potential to make CT an ideal noninvasive gate-keeper for invasive coronary angiography. However, beam hardening artifacts (BHA) prevent accurate blood flow calculation in MPI-CT. BH Correction (BHC) methods require either energy-sensitive CT, not widely available, or typically a calibration-based method. We developed a calibration-free, automatic BHC (ABHC) method suitable for MPI-CT. The algorithm works with any BHC method and iteratively determines model parameters using proposed BHA-specific cost function. In this work, we use the polynomial BHC extended to three materials. The image is segmented into soft tissue, bone, and iodine images, based on mean HU and temporal enhancement. Forward projections of bone and iodine images are obtained, and in each iteration polynomial correction is applied. Corrections are then back projected and combined to obtain the current iteration's BHC image. This process is iterated until cost is minimized. We evaluate the algorithm on simulated and physical phantom images and on preclinical MPI-CT data. The scans were obtained on a prototype spectral detector CT (SDCT) scanner (Philips Healthcare). Mono-energetic reconstructed images were used as the reference. In the simulated phantom, BH streak artifacts were reduced from 12+/-2HU to 1+/-1HU and cupping was reduced by 81%. Similarly, in physical phantom, BH streak artifacts were reduced from 48+/-6HU to 1+/-5HU and cupping was reduced by 86%. In preclinical MPI-CT images, BHA was reduced from 28+/-6 HU to less than 4+/-4HU at peak enhancement. Results suggest that the algorithm can be used to reduce BHA in conventional CT and improve MPI-CT accuracy.

  1. Noncardiac findings on cardiac CT. Part II: spectrum of imaging findings.

    LENUS (Irish Health Repository)

    Killeen, Ronan P

    2012-02-01

    Cardiac computed tomography (CT) has evolved into an effective imaging technique for the evaluation of coronary artery disease in selected patients. Two distinct advantages over other noninvasive cardiac imaging methods include its ability to directly evaluate the coronary arteries and to provide a unique opportunity to evaluate for alternative diagnoses by assessing the extracardiac structures, such as the lungs and mediastinum, particularly in patients presenting with the chief symptom of acute chest pain. Some centers reconstruct a small field of view (FOV) cropped around the heart but a full FOV (from skin to skin in the area irradiated) is obtainable in the raw data of every scan so that clinically relevant noncardiac findings are identifiable. Debate in the scientific community has centered on the necessity for this large FOV. A review of noncardiac structures provides the opportunity to make alternative diagnoses that may account for the patient\\'s presentation or to detect important but clinically silent problems such as lung cancer. Critics argue that the yield of biopsy-proven cancers is low and that the follow-up of incidental noncardiac findings is expensive, resulting in increased radiation exposure and possibly unnecessary further testing. In this 2-part review we outline the issues surrounding the concept of the noncardiac read, looking for noncardiac findings on cardiac CT. Part I focused on the pros and cons for and against the practice of identifying noncardiac findings on cardiac CT. Part II illustrates the imaging spectrum of cardiac CT appearances of benign and malignant noncardiac pathology.

  2. Exposure (mAs) optimisation of a multi-detector CT protocol for hepatic lesion detection: are thinner slices better?

    International Nuclear Information System (INIS)

    The purpose of this work was to determine the exposure-optimised slice thickness for hepatic lesion detection with CT. A phantom containing spheres (diameter 9.5, 4.8 and 2.4mm) with CT density 10 HU below the background (50 HU) was scanned at 125, 100, 75 and 50 mAs. Data were reconstructed at 5-, 3- and 1-mm slice thicknesses. Noise, contrast-to-noise ratio (CNR), area under the curve (AUC) as calculated using receiver operating characteristic analysis and sensitivity representing lesion detection were calculated and compared. Compared with the 125 mAs/5mm slice thickness setting, significant reductions in AUC were found for 75 mAs (P<0.01) and 50 mAs (P<0.05) at 1- and 3-mm thicknesses, respectively; sensitivity for the 9.5-mm sphere was significantly reduced for 75 (P<0.05) and 50 mAs (P<0.01) at 1-mm thickness; sensitivity for the 4.8-mm sphere was significantly lower for 100, 75 and 50 mAs at all three slice thicknesses (P<0.05). The 2.4-mm sphere was rarely detected. At each slice thickness, noise at 100, 75 and 50 mAs exposures was approximately 10, 30 and 50% higher, respectively, than that at 125 mAs exposure. CNRs decreased in an irregular manner with reductions in exposure and slice thickness. This study demonstrated no advantage to using slices below 5mm thickness, and consequently thinner slices are not necessarily better.

  3. Usefulness of biphasic contrast injection in multidetector CT of the head and neck: A comparison with monophasic contrast injection

    International Nuclear Information System (INIS)

    The purpose of this study was to evaluate the value of biphasic injection of contrast media in a CT of the head and neck. In the first step, vessel and tissue attenuation was measured in four different protocol groups: M1 (monophasic, injection rate: 100 mL at 3 mL/sec, delay time: 70 sec); B1 (biphasic, 100 mL at 3 mL/sec, 70 sec); M2 (monophasic, 100 mL at 2 mL/sec, 70 sec); and B2 (biphasic, 100 mL at 2 mL/sec, 120 sec). The biphasic injection protocol was an initial volus injection of 50 mL contrast medium and an additional volus injection of 50 mL contrast medium at 35 sec after initial injection. In the second step, the tissue attenuation of two groups was measured with a different contrast media volume and phase: M3 (monophasic, 100 mL at 2 mL/sec, 90 sec) and B3 (biphasic, 80 mL at 2 mL/sec, 90 sec, initial volus injection of 40 mL and an additional volus injection of 40 mL at 55 sec after initial injection). The measured CT numbers from vessels and tissues were compared between the different protocol groups. The vessel attenuation of B1 was higher than that of M1 and B2 (p < 0.05). Despite a longer delay time, the vessel attenuation of B2 was not significantly different from that of M1 and M2. There was no significant differentiation of tissue attenuation between each group. In the second study, the attenuation of vessel and tissue was not different between B3 and M3. Biphasic contrast injection leads to an increased attenuation of the vessel and also delays the optimal scan window

  4. The added diagnostic value of 64-row multidetector CT combined with contrast-enhanced US in the evaluation of hepatocellular nodule vascularity: implications in the diagnosis of malignancy in patients with liver cirrhosis

    International Nuclear Information System (INIS)

    The aim of this study was to assess the added diagnostic value of contrast-enhanced US (CEUS) combined with 64-row multidetector CT (CT) in the assessment of hepatocellular nodule vascularity in patients with liver cirrhosis. One hundred and six cirrhotic patients (68 male, 38 female; mean age ± SD, 70 ± 7 years) with 121 biopsy-proven hepatocellular nodules (72 hepatocellular carcinomas, 10 dysplastic and 15 regenerative nodules, 12 hemangiomas, and 12 other benignancies) detected during US surveillance were prospectively recruited. Each nodule was scanned by CEUS during the arterial (10-40 s), portal venous (45-90 s), and delayed sinusoidal phase (from 100 s after microbubble injection to microbubble disappearance). Nodule vascularity at CEUS, CT, and combined CEUS/CT was evaluated side-by-side by two independent blinded readers who classified nodules as benign or malignant according to reference diagnostic criteria. The combined assessment of CEUS/CT provided higher sensitivity (97%, both readers) than did separate assessment of CEUS (88% reader 1; 87% reader 2) and CT (74% reader 1; 71% reader 2; P < 0.05), while no change in specificity was provided by combined analysis. The combined assessment of hepatocellular nodule vascularity at CT and CEUS improved sensitivity in the diagnosis of malignancy in patients with liver cirrhosis. (orig.)

  5. The utility of cardiac CT beyond the assessment of suspected coronary artery disease

    Energy Technology Data Exchange (ETDEWEB)

    Kakouros, N. [Johns Hopkins Hospital, Baltimore, MD (United States); Giles, J.; Crundwell, N.B. [Conquest Hospital, St Leonards-on-Sea, East Sussex (United Kingdom); McWilliams, E.T.M., E-mail: eric.mcwilliams@esht.nhs.uk [Conquest Hospital, St Leonards-on-Sea, East Sussex (United Kingdom)

    2012-07-15

    Extensive work has been done over recent years to improve the spatial and temporal resolution of electrocardiogram (ECG)-gated cardiac computed tomography (CT). Advances in both hardware and software analysis have enabled the development of non-invasive coronary angiography. However, these high-quality examinations lend themselves to multiple additional applications beyond coronary angiography. In this review, we illustrate and discuss some established and some emerging applications of ECG-gated cardiac CT beyond the assessment of suspected coronary disease, particularly in light of recent recommendations on the appropriate use of this technology.

  6. Subcutaneous Tissue Thickness is an Independent Predictor of Image Noise in Cardiac CT

    OpenAIRE

    Staniak, Henrique Lane; Sharovsky, Rodolfo; Pereira, Alexandre Costa; de Castro, Cláudio Campi; Isabela M. Benseñor; Paulo A Lotufo; Bittencourt, Márcio Sommer

    2014-01-01

    Background Few data on the definition of simple robust parameters to predict image noise in cardiac computed tomography (CT) exist. Objectives To evaluate the value of a simple measure of subcutaneous tissue as a predictor of image noise in cardiac CT. Methods 86 patients underwent prospective ECG-gated coronary computed tomographic angiography (CTA) and coronary calcium scoring (CAC) with 120 kV and 150 mA. The image quality was objectively measured by the image noise in the aorta in the car...

  7. The utility of cardiac CT beyond the assessment of suspected coronary artery disease

    International Nuclear Information System (INIS)

    Extensive work has been done over recent years to improve the spatial and temporal resolution of electrocardiogram (ECG)-gated cardiac computed tomography (CT). Advances in both hardware and software analysis have enabled the development of non-invasive coronary angiography. However, these high-quality examinations lend themselves to multiple additional applications beyond coronary angiography. In this review, we illustrate and discuss some established and some emerging applications of ECG-gated cardiac CT beyond the assessment of suspected coronary disease, particularly in light of recent recommendations on the appropriate use of this technology.

  8. Coronary ostial involvement in acute aortic dissection: detection with 64-slice cardiac CT.

    LENUS (Irish Health Repository)

    Ryan, E Ronan

    2012-02-01

    A 41-year-old man collapsed after lifting weights at a gym. Following admission to the emergency department, a 64-slice cardiac computed tomography (CT) revealed a Stanford Type A aortic dissection arising from a previous coarctation repair. Multiphasic reconstructions demonstrated an unstable, highly mobile aortic dissection flap that extended proximally to involve the right coronary artery ostium. Our case is an example of the application of electrocardiogram-gated cardiac CT in directly visualizing involvement of the coronary ostia in acute aortic dissection, which may influence surgical management.

  9. Assessments of Coronary Artery Visibility and Radiation Dose in Infants with Congenital Heart Disease on Cardiac 128-slice CT and on Cardiac 64-slice CT.

    Science.gov (United States)

    Cui, Y; Huang, M; Zheng, J; Li, J; Liu, H; Liang, C

    2016-01-01

    The aim of this study was to compare the coronary artery visibility and radiation dose in infants with CHD on cardiac 128-slice CT and on cardiac 64-slice CT. The images of 200 patients were analyzed in this study, 100 patients were selected randomly from a group of 789 infants (ECG-triggered axial scan, and 100 were selected randomly from 911 infants with CHD undergoing 64-slice CT retrospective ECG-gated spiral scan. The visibility of coronary artery segments was graded on a four-point scale. The coronary arteries were considered to be detected or visible when grade was 2 or higher. The visibility of the coronary artery segments and the radiation dose was compared between the two groups. Except for the rate of LM (96 vs. 99%), the detection rates of the total, LAD, LCX, RCA, and the proximal segment of the RCA in the 256-slice CT group were significantly higher than those in the 64-slice CT group (51.7, 53.33, 33.67, 53.33, and 99 vs. 34.8, 34.33, 18, 30.67, and 75%, respectively). The counts of visibility score (4/3/2/1) for the LM and the proximal segment of the RCA were 62/22/12/4 and 56/20/17/7, respectively, in the 128-slice CT group and 17/42/30/1 and 9/30/38/25, respectively, in the 64-slice CT group. There were significant differences, especially for score 4 and 3, between the two groups. The radiation dose in the 128-slice CT group was significantly decreased than those in the 64-slice CT group (CTDIvol 1.88 ± 0.51 vs. 5.61 ± 0.63 mGy; SSDE 4.48 ± 1.15 vs. 13.97 ± 1.52 mGy; effective radiation dose 1.36 ± 0.44 vs. 4.06 ± 0.7 mSv). With reduced radiation dose, the visibility of the coronary artery in infants with CHD via prospective ECG-triggered mode on a 128-slice CT is superior to that of the 64-slice CT using retrospective ECG-gated spiral mode. PMID:26271472

  10. Comparison of accuracy of aortic root annulus assessment with cardiac magnetic resonance versus echocardiography and multidetector computed tomography in patients referred for transcatheter aortic valve implantation.

    Science.gov (United States)

    Pontone, Gianluca; Andreini, Daniele; Bartorelli, Antonio L; Bertella, Erika; Mushtaq, Saima; Gripari, Paola; Loguercio, Monica; Cortinovis, Sarah; Baggiano, Andrea; Conte, Edoardo; Beltrama, Virginia; Annoni, Andrea; Formenti, Alberto; Tamborini, Gloria; Muratori, Manuela; Guaricci, Andrea; Alamanni, Francesco; Ballerini, Giovanni; Pepi, Mauro

    2013-12-01

    The evaluation of the aortic root in patients referred for transcatheter aortic valve implantation is crucial. The aim of the present study was to compare the accuracy of cardiac magnetic resonance (CMR) evaluation of the aortic annulus (AoA) with transthoracic and transesophageal echocardiography and multidetector computed tomography (MDCT) in patients referred for transcatheter aortic valve implantation. In 50 patients, maximum diameter, minimum diameter and AoA, length of the left coronary, right coronary, and noncoronary aortic leaflets, degree (grades 1 to 4) of aortic leaflet calcification, and distance between AoA and coronary artery ostia were assessed. AoA maximum diameter, minimum diameter, and area by CMR were 26.4 ± 2.8 mm, 20.6 ± 2.3 mm, 449.8 ± 86.2 mm(2), respectively. The length of left coronary, right coronary, and noncoronary leaflets by CMR were 13.9 ± 2.2, 13.3 ± 2.1, and 13.4 ± 1.8 mm, respectively, whereas the score of aortic leaflet calcifications was 2.9 ± 0.8. Finally, the distances between AoA and left main and right coronary artery ostia were 16.1 ± 2.8 and 16.1 ± 4.4 mm, respectively. Regarding AoA area, transthoracic and transesophageal echocardiography showed an underestimation (p <0.01), with a moderate agreement (r: 0.5 and 0.6, respectively, p <0.01) compared with CMR. No differences and excellent correlation were observed between CMR and MDCT for all parameters (r: 0.9, p <0.01), except for aortic leaflet calcifications that were underestimated by CMR. In conclusion, aortic root assessment with CMR including AoA size, aortic leaflet length, and coronary artery ostia height is accurate compared with MDCT. CMR may be a valid imaging alternative in patients unsuitable for MDCT. PMID:24045059

  11. 药物性肝损害的多层螺旋CT影像表现%Drug-induced liver injury: spectrum of multi-detector spiral CT findings

    Institute of Scientific and Technical Information of China (English)

    宋文艳; 赵大伟; 陈煜; 刘旭华; 孟欣; 陈枫

    2010-01-01

    目的 探讨药物性肝损伤的MSCT表现.方法 回顾性分析2008年5月至2010年1月间经临床及病理证实的40例药物性肝损伤患者的MSCT影像及临床资料,总结其影像表现特征.结果 药物性肝损伤的MSCT影像表现主要有3种类型.(1)弥漫性肝脏损害2例:平扫肝脏密度均匀性减低,增强扫描肝实质轻度均匀强化.病理表现为肝细胞脂肪变性;混合炎性细胞浸润,点状坏死,毛细胆管淤胆.(2)灶性肝脏损害6例:肝内大片或多发小片状坏死灶5例.平扫肝脏密度不均匀,病变区为低密度改变;增强后病变区强化,特别是静脉期与平扫图像比较呈反转表现.另1例病程20 d的移植肝显示肝内弥漫的结节样再生.CT平扫可见肝内弥漫分布的稍高密度结节灶,增强后动脉期病灶强化,静脉期及延迟期近似于肝实质密度.5例患者病理表现为肝细胞片状及桥接坏死,大量混合炎性细胞浸润;1例重度淤胆,假小叶形成,肝细胞羽毛变性.(3)肝硬化表现2例:平扫肝脏表面呈结节状,肝叶比例失调,肝裂增宽.增强后肝脏强化一致,同时伴有脾大、腹水、侧支循环.病理为纤维组织增生,点状坏死和毛细胆管淤胆.结论 药物性肝损伤的MSCT影像表现具有一定的特征性,对临床诊断具有重要的参考价值.%Objective To demonstrate the spectrum of multi-detector spiral CT (MSCT) findings of drug-induced liver injury (DILI). Methods From May 2008 to January 2010, DILI was identified in 10 cases based on their clinical and pathological results. The spectrum of CT findings was analyzed retrospectively. Results According to the CT features, DILI were divided into three types. ( 1 ) Two cases presented diffuse hepatic injury, which appeared as homogeneous hypo-attenuation in precontrast CT scan and mild enhancement after contrast injection. The histopathological findings of the involved 1ivers include hepatocellular steatosis, neutrophil and

  12. Noninvasive Physiologic Assessment of Coronary Stenoses Using Cardiac CT

    Directory of Open Access Journals (Sweden)

    Lei Xu

    2015-01-01

    Full Text Available Coronary CT angiography (CCTA has become an important noninvasive imaging modality in the diagnosis of coronary artery disease (CAD. CCTA enables accurate evaluation of coronary artery stenosis. However, CCTA provides limited information on the physiological significance of stenotic lesions. A noninvasive “one-stop-shop” diagnostic test that can provide both anatomical significance and functional significance of stenotic lesions would be beneficial in the diagnosis and management of CAD. Recently, with the introduction of novel techniques, such as myocardial CT perfusion, CT-derived fractional flow reserve (FFRCT, and transluminal attenuation gradient (TAG, CCTA has emerged as a noninvasive method for the assessment of both anatomy of coronary lesions and its physiological consequences during a single study. This review provides an overview of the current status of new CT techniques for the physiologic assessments of CAD.

  13. Defining the mid-diastolic imaging period for cardiac CT – lessons from tissue Doppler echocardiography

    Directory of Open Access Journals (Sweden)

    Otton James M

    2013-02-01

    Full Text Available Abstract Background Aggressive dose reduction strategies for cardiac CT require the prospective selection of limited cardiac phases. At lower heart rates, the period of mid-diastole is typically selected for image acquisition. We aimed to identify the effect of heart rate on the optimal CT acquisition phase within the period of mid-diastole. Methods We utilized high temporal resolution tissue Doppler to precisely measure coronary motion within diastole. Tissue-Doppler waveforms of the myocardium corresponding to the location of the circumflex artery (100 patients and mid-right coronary arteries (50 patients and the duration and timing of coronary motion were measured. Using regression analysis an equation was derived for the timing of the period of minimal coronary motion within the RR interval. In a validation set of 50 clinical cardiac CT examinations, we assessed coronary motion artifact and the effect of using a mid-diastolic imaging target that was adjusted according to heart rate vs a fixed 75% phase target. Results Tissue Doppler analysis shows the period of minimal cardiac motion suitable for CT imaging decreases almost linearly as the RR interval decreases, becoming extinguished at an average heart rate of 91 bpm for the circumflex (LCX and 78 bpm for the right coronary artery (RCA. The optimal imaging phase has a strong linear relationship with RR duration (R2 = 0.92 LCX, 0.89 RCA. The optimal phase predicted by regression analysis of the tissue-Doppler waveforms increases from 74% at a heart rate of 55 bpm to 77% at 75 bpm. In the clinical CT validation set, the optimal CT acquisition phase similarly occurred later with increasing heart rate. When the selected cardiac phase was adjusted according to heart rate the result was closer to the optimal phase than using a fixed 75% phase. While this effect was statistically significant (p  Conclusion High temporal resolution imaging of coronary motion can be used to predict the optimal

  14. Diagnostic Value of Brain Perfusion Imaging with 64 Multi-Detector Spiral CT in Early Cerebral Infarction%64排螺旋 CT 脑灌注成像对早期脑梗死的诊断价值

    Institute of Scientific and Technical Information of China (English)

    奚彬; 盛伟华; 唐建伟; 黄松; 宋黎涛

    2014-01-01

    目的:探讨64排螺旋 CT 脑灌注成像(CT perfusion imaging,CTP)对早期脑梗死的诊断价值。方法:临床拟诊早期脑梗死患者38例,均在症状出现24 h 内行头颅 CT 平扫及 CTP 检查。将脑梗死核心区、缺血半暗带(ischemic penumbra,IP)区与健侧对应区的情况做对比分析。结果:38例患者中,15例头颅 CT 平扫发现可疑脑梗死区,主要位于大脑半球,表现为密度轻度减低、局部脑沟稍变浅等;其余23例患者 CT 平扫未发现异常。38例患者的 CTP 检查均发现灌注异常区,表现为脑梗死区脑血流量(cerebral blood flow,CBF)与脑血容量(cerebral blood volume,CBV)均较健侧对应区明显下降,对比剂平均通过时间(mean transit time,MTT)较健侧对应区缩短,对比剂达峰时间(time to peak,TTP)较健侧对应区明显延长,差异均有统计学意义(P <0.01)。早期脑梗死患者 IP 区与梗死核心区比较,CBF、CBV、MTT 及 TTP 差异均有统计学意义(P <0.01);IP区与健侧对应区比较,CBF、MTT、TTP 差异均有统计学意义(P <0.05、0.01),CBV 差异无统计学意义(P >0.05)。获得随访的18例患者中,经积极溶栓等治疗后梗死区缩小6例,梗死区消失5例,仅表现为梗死区 TTP 和 MTT 延长、CBF 和 CBV 变化不大3例,梗死区无明显变化4例。结论:64排螺旋 CTP 检查可以准确地提示早期脑梗死。%Objective:To explore the diagnostic value of CT perfusion imaging(CTP)with 64 multi-detector spiral CT in early cerebral infarction.Methods:A total of 38 patients with suspected early cerebral infarction underwent plain CT and CTP within 24 h after the onset of related symptoms.The imaging results in infarction core area,ischemic penumbra (IP) and the contralateral normal region were comparatively analyzed.Results:Early cerebral infarction,mainly in cerebral hemispheres, were suspected

  15. Assessments of Coronary Artery Visibility and Radiation Dose in Infants with Congenital Heart Disease on Cardiac 128-slice CT and on Cardiac 64-slice CT.

    Science.gov (United States)

    Cui, Y; Huang, M; Zheng, J; Li, J; Liu, H; Liang, C

    2016-01-01

    The aim of this study was to compare the coronary artery visibility and radiation dose in infants with CHD on cardiac 128-slice CT and on cardiac 64-slice CT. The images of 200 patients were analyzed in this study, 100 patients were selected randomly from a group of 789 infants (coronary artery segments was graded on a four-point scale. The coronary arteries were considered to be detected or visible when grade was 2 or higher. The visibility of the coronary artery segments and the radiation dose was compared between the two groups. Except for the rate of LM (96 vs. 99%), the detection rates of the total, LAD, LCX, RCA, and the proximal segment of the RCA in the 256-slice CT group were significantly higher than those in the 64-slice CT group (51.7, 53.33, 33.67, 53.33, and 99 vs. 34.8, 34.33, 18, 30.67, and 75%, respectively). The counts of visibility score (4/3/2/1) for the LM and the proximal segment of the RCA were 62/22/12/4 and 56/20/17/7, respectively, in the 128-slice CT group and 17/42/30/1 and 9/30/38/25, respectively, in the 64-slice CT group. There were significant differences, especially for score 4 and 3, between the two groups. The radiation dose in the 128-slice CT group was significantly decreased than those in the 64-slice CT group (CTDIvol 1.88 ± 0.51 vs. 5.61 ± 0.63 mGy; SSDE 4.48 ± 1.15 vs. 13.97 ± 1.52 mGy; effective radiation dose 1.36 ± 0.44 vs. 4.06 ± 0.7 mSv). With reduced radiation dose, the visibility of the coronary artery in infants with CHD via prospective ECG-triggered mode on a 128-slice CT is superior to that of the 64-slice CT using retrospective ECG-gated spiral mode.

  16. Acute subarachnoid hemorrhage: using 64-slice multidetector CT angiography to ''triage'' patients' treatment

    Energy Technology Data Exchange (ETDEWEB)

    Agid, R.; Lee, S.K.; Willinsky, R.A.; Farb, R.I.; TerBrugge, K.G. [Toronto Western Hospital, Division of Neuroradiology, Department of Medical Imaging, Toronto, Ontario (Canada)

    2006-11-15

    To evaluate the clinical role of CT angiography (CTA) in patients with acute subarachnoid hemorrhage (SAH) for treatment decision-making. Consecutive patients with acute SAH had CTA using a 64-slice scanner for initial clinical decision-making. Image processing included multiplanar volume reformatted (MPVR) maximum intensity projections (MIP) and 3D volume-rendered reconstructions. CTAs were used for (1) evaluating the cause of SAH, and (2) triaging aneurysm-bearing patients to the more appropriate management, either surgical clipping or endovascular coiling. CTA findings were confirmed by neurosurgical exploration or catheter angiography (digital subtraction angiography, DSA). Successful coiling provided evidence that triaging to endovascular treatment was correct. Included in the study were 73 patients. CTA findings were confirmed by DSA or neurosurgical operation in 65 patients, and of these 65, 47 had aneurysmal SAH, 3 had vasculitis, 1 had arterial dissection and 14 had no underlying arterial abnormality. The cause of SAH was detected with CTA in 62 out of the 65 patients (95.4%, sensitivity 94%, specificity 100%). CTA revealed the aneurysm in 46 of 47 patients (98%, sensitivity 98%, specificity 100%, positive predictive value 100%, negative predictive value 82.3%), 1 of 3 vasculitides and 1 of 1 dissection. Of the 46 patients with aneurysm, 44 (95.7%) were referred for treatment based on CTA. In 2 patients (2 of 46, 4.4%) CTA was not informative enough to choose treatment requiring DSA. Of the 44 patients, 27 (61.4%) were referred to endovascular treatment and successful coiling was achieved in 25 (25 of 27, 92.6%). CTA using a 64-slice scanner is an accurate tool for detecting and characterizing aneurysms in acute SAH. CTA is useful in the decision process whether to coil or clip an aneurysm. (orig.)

  17. Liver tumour segmentation using contrast-enhanced multi-detector CT data: performance benchmarking of three semiautomated methods

    International Nuclear Information System (INIS)

    Automatic tumour segmentation and volumetry is useful in cancer staging and treatment outcome assessment. This paper presents a performance benchmarking study on liver tumour segmentation for three semiautomatic algorithms: 2D region growing with knowledge-based constraints (A1), 2D voxel classification with propagational learning (A2) and Bayesian rule-based 3D region growing (A3). CT data from 30 patients were studied, and 47 liver tumours were isolated and manually segmented by experts to obtain the reference standard. Four datasets with ten tumours were used for algorithm training and the remaining 37 tumours for testing. Three evaluation metrics, relative absolute volume difference (RAVD), volumetric overlap error (VOE) and average symmetric surface distance (ASSD), were computed based on computerised and reference segmentations. A1, A2 and A3 obtained mean/median RAVD scores of 17.93/10.53%, 17.92/9.61% and 34.74/28.75%, mean/median VOEs of 30.47/26.79%, 25.70/22.64% and 39.95/38.54%, and mean/median ASSDs of 2.05/1.41 mm, 1.57/1.15 mm and 4.12/3.41 mm, respectively. For each metric, we obtained significantly lower values of A1 and A2 than A3 (P < 0.01), suggesting that A1 and A2 outperformed A3. Compared with the reference standard, the overall performance of A1 and A2 is promising. Further development and validation is necessary before reliable tumour segmentation and volumetry can be widely used clinically. (orig.)

  18. Depiction of variants of the portal confluence venous system using multidetector row CT. Analysis of 916 cases

    Energy Technology Data Exchange (ETDEWEB)

    Krumm, P.; Schraml, C.; Bretschneider, C.; Seeger, A.; Klumpp, B.; Kramer, U.; Claussen, C.D.; Miller, S. [Universitaetsklinikum Tuebingen (Germany). Abt. fuer Diagnostische und Interventionelle Radiologie

    2011-12-15

    Purpose: Detailed knowledge of the venous mesenteric system is important for gastrointestinal surgery, particularly for transplantation planning and surgery and for the comprehension of perioperative complications that may influence patient outcome. Data about the mesenteric venous anatomy in the literature varies substantially. The purpose of this study was to categorize venous mesenteric variants and to determine their incidence. Materials and Methods: We included 916 patients requiring diagnostic abdominal CT in the portal venous phase. The mesenteric vein anatomy was categorized as follows: 1. the inferior mesenteric vein (IMV) enters the splenic vein (SV); 2. the IMV enters into the angle of the confluence of the SV and superior mesenteric vein (SMV) forming the portal vein (PV); 3. the IMV enters the SMV; 4. seven rare variants. We measured the diameters of the veins and distances from the confluence to the IMV origins. Results: The frequency of variants was: 1. 37.6 %, 2. 28.8 %; 3. 19.2 %. The rare variants totaled 14.4 %. The average vessel diameters measured in cm: PV 1.48; SV 1.02; SMV 1.2; IMV 0.5. The mean IMV entering distances were 1.66 cm in variant 1 and 0.75 cm in variant 3. Conclusion: The three common variants (1, 2 and 3) are the most relevant ones. 14.4 % of patients had different anatomic variants. The variability of the mesenteric venous system was higher than previously published. Knowledge of rare variants is important to avoid complications in abdominal surgery. (orig.)

  19. 4D micro-CT for cardiac and perfusion applications with view under sampling

    Energy Technology Data Exchange (ETDEWEB)

    Badea, Cristian T; Johnston, Samuel M; Qi Yi; Johnson, G Allan, E-mail: Cristian.Badea@duke.edu [Center for In Vivo Microscopy, Box 3302, Duke University Medical Center, Durham, NC 27710 (United States)

    2011-06-07

    Micro-CT is commonly used in preclinical studies to provide anatomical information. There is growing interest in obtaining functional measurements from 4D micro-CT. We report here strategies for 4D micro-CT with a focus on two applications: (i) cardiac imaging based on retrospective gating and (ii) pulmonary perfusion using multiple contrast injections/rotations paradigm. A dual source micro-CT system is used for image acquisition with a sampling rate of 20 projections per second. The cardiac micro-CT protocol involves the use of a liposomal blood pool contrast agent. Fast scanning of free breathing mice is achieved using retrospective gating. The ECG and respiratory signals are used to sort projections into ten cardiac phases. The pulmonary perfusion protocol uses a conventional contrast agent (Isovue 370) delivered by a micro-injector in four injections separated by 2 min intervals to allow for clearance. Each injection is synchronized with the rotation of the animal, and each of the four rotations is started with an angular offset of 22.5 from the starting angle of the previous rotation. Both cardiac and perfusion protocols result in an irregular angular distribution of projections that causes significant streaking artifacts in reconstructions when using traditional filtered backprojection (FBP) algorithms. The reconstruction involves the use of the point spread function of the micro-CT system for each time point, and the analysis of the distribution of the reconstructed data in the Fourier domain. This enables us to correct for angular inconsistencies via deconvolution and identify regions where data is missing. The missing regions are filled with data from a high quality but temporally averaged prior image reconstructed with all available projections. Simulations indicate that deconvolution successfully removes the streaking artifacts while preserving temporal information. 4D cardiac micro-CT in a mouse was performed with adequate image quality at isotropic

  20. Diagnostic Value of Multidetector CT and Its Multiplanar Reformation, Volume Rendering and Virtual Bronchoscopy Postprocessing Techniques for Primary Trachea and Main Bronchus Tumors.

    Directory of Open Access Journals (Sweden)

    Mingyue Luo

    Full Text Available To evaluate the diagnostic value of multidetector CT (MDCT and its multiplanar reformation (MPR, volume rendering (VR and virtual bronchoscopy (VB postprocessing techniques for primary trachea and main bronchus tumors.Detection results of 31 primary trachea and main bronchus tumors with MDCT and its MPR, VR and VB postprocessing techniques, were analyzed retrospectively with regard to tumor locations, tumor morphologies, extramural invasions of tumors, longitudinal involvements of tumors, morphologies and extents of luminal stenoses, distances between main bronchus tumors and trachea carinae, and internal features of tumors. The detection results were compared with that of surgery and pathology.Detection results with MDCT and its MPR, VR and VB were consistent with that of surgery and pathology, included tumor locations (tracheae, n = 19; right main bronchi, n = 6; left main bronchi, n = 6, tumor morphologies (endoluminal nodes with narrow bases, n = 2; endoluminal nodes with wide bases, n = 13; both intraluminal and extraluminal masses, n = 16, extramural invasions of tumors (brokethrough only serous membrane, n = 1; 4.0 mm-56.0 mm, n = 14; no clear border with right atelectasis, n = 1, longitudinal involvements of tumors (3.0 mm, n = 1; 5.0 mm-68.0 mm, n = 29; whole right main bronchus wall and trachea carina, n = 1, morphologies of luminal stenoses (irregular, n = 26; circular, n = 3; eccentric, n = 1; conical, n = 1 and extents (mild, n = 5; moderate, n = 7; severe, n = 19, distances between main bronchus tumors and trachea carinae (16.0 mm, n = 1; invaded trachea carina, n = 1; >20.0 mm, n = 10, and internal features of tumors (fairly homogeneous densities with rather obvious enhancements, n = 26; homogeneous density with obvious enhancement, n = 1; homogeneous density without obvious enhancement, n = 1; not enough homogeneous density with obvious enhancement, n = 1; punctate calcification with obvious enhancement, n = 1; low density

  1. Correlation between morphologic carotid plaque findings based on color-Doppler and CT multidetector angiography with intraopertive findings in carotid artery stenosis

    Directory of Open Access Journals (Sweden)

    Savić Živorad N.

    2010-01-01

    Full Text Available Bacground/Aim. Vast majority of patients with corotid artery sclerosis do not have transitory ischemic attacks (TIA as working to the persistent silent disease, but stroke is the first sign. Precise and early diagnosis of the carotid artery disease and plaques are very important. The aim of this study was to determine how the composition / identity of diagnostic methods, color-Doppler, ultrasonography (US CT multidetector angio (MDCTA scan and intraoperative (IO findings, as well as the morphology of plaques in patients with haemodynamic significant stenosis of the internal carotid artery. Methods. Carotid plaques were observed by two diagnostic methods, US and MDCTA, and these findings were correlated with the IO findings. Results. In 62 patients both carotid artheries were examined and 83 plaques were observed. There were 68 surgical interventions. The structure of plaques was divided into four types: lipid, fibrous, fibrocalcified and calcified plaque. US showed: lipid plaques 10.8%; fibrous 1.2%; fibrocalcified 44.6% and calcified 43.4%, and the MDCTA lipid plaques 8.4%; fibrocalcified 48.2% and calcified 43.4%. Intraoperative findings were: lipid plaques 10.3%; fibrocalcified 41.2% and calcified 48.5%. A statistically highly significant agreement between the US and MDCTA in the diagnosis of plaque morphology was obtained (Cramer's V = 0.919, p < 0.01; Lambda = 0.921, p < 0.01 and also statistically significant agreement between US and IO findings (Cramer' s V = 0.831, p < 0.01; Lambda = 0.859, p < 0.01. A statistically highly significant agreement between MDCTA and IO findings in plaque morphology was found, as well (Cramer's V = 0.815, p < 0.01; Lambda = 0.829, p < 0.01. Conclusion. There is statistically highly significant correlation between US and MDCTA diagnostic methods in the evaluation of plaque morphology in surgically significant stenosis of internal carotid artery as well as their agreement with the intraoperative finding.

  2. Diagnosis of chronic thromboembolic pulmonary hypertension: prospective comparison of ventilation-perfusion scintigraphy and multidetector CT pulmonary angiography

    International Nuclear Information System (INIS)

    Objective: To compare the diagnostic efficacy of V/Q scintigraphy and CT pulmonary angiography (CTPA) for chronic thromboembolic PAH (CTEPH). Methods: A total of 133 consecutive patients (54 males, 79 females, age:(43.1 ± 14.9) years) suspected of CTEPH were prospectively enrolled in the study. All patients underwent V/Q scintigraphy, CTPA and pulmonary angiography within 7 d of clinical presentation. Pulmonary angiography was considered as the gold standard. The diagnosis of CTEPH by V/Q scan was classified as high, intermediate and low probability, and that by CTPA was classified as present, absent and indeterminate. Kappa test was used to analyze the concordance between the image modalities. Results: Fifty-one patients (38.3%) had a final diagnosis of CTEPH. The other 82 patients were respectively diagnosed with IPAH (n=60), pulmonary vasculitis (n=19) and atrial septal defect (n=3). The sensitivity, specificity and accuracy of V/Q scan were 96.1% (49/51), 75.6% (62/82) and 83.5% (111/133), respectively, when CTEPH with high probability was considered positive. The sensitivity, specificity and accuracy of V/Q scan were 100% (51/51), 73.2% (60/82) and 83.5% (111/133), respectively, when CTEPH with high or intermediate probability was considered positive. The sensitivity, specificity and accuracy of CTPA were 92.2% (47/51), 92.7% (76/82) and 92.5% (123/133), respectively. When CTEPH with high probability by V/Q scan was considered positive, the concordance between V/Q scan and CTPA was 80.5% (107/133) (Kappa=0.612, P<0.001). Conclusions: V/Q scan has a higher sensitivity for the diagnosis of CTEPH than CTPA. CTPA has a higher specificity than V/Q scan to differentiate PAH caused by other diseases, especially pulmonary vasculitis,from CTEPH. Combining V/Q scan and CTPA may improve the diagnostic accuracy of CTEPH. (authors)

  3. Time-resolved cardiac cone beam CT using an interventional C-arm system

    NARCIS (Netherlands)

    Schomberg, H.

    2012-01-01

    It is both desirable and challenging to make interventional C-arm systems fit for cardiac cone beam CT. A number of methods towards thisgoal have been proposed, some of which even attempt to generate 4Dimages of the beating heart. A promising candidate of this type, proposed earlier by this author,

  4. Comparison of 64-row and 16-row multidetector CT in the perfusion CT evaluation of acute ischemic stroke patients receiving intravenous thrombolytic therapy

    Energy Technology Data Exchange (ETDEWEB)

    Sillanpaa, Niko; Dastidar, Prasun; Soimakallio, Seppo [Tampere University Hospital, Medical Imaging Centre, PL 2000, Tampere (Finland); Rusanen, Harri [Oulu University Hospital, Department of Neurology, Oulu (Finland); Saarinen, Jukka T. [Tampere University Hospital, Department of Neurology, Tampere (Finland)

    2012-09-15

    Perfusion computed tomography (PCT) is increasingly performed in multimodal CT evaluation of acute ischemic stroke. We compared the technical quality of perfusion studies performed with a 16-row and a 64-row scanner and analyzed the differences between the scanners in their ability to detect perfusion defects. We analyzed retrospectively the clinical and imaging data of 140 consecutive acute (<3 h) stroke patients who underwent multimodal CT evaluation and received intravenous rtPA. Alberta Stroke Program Early CT Score (ASPECTS) was assigned to PCT maps. Clinical and imaging parameters were compared between the two scanners. There were more motion artifacts in the 16-row studies (p = 0.04), and the analysis software was able to completely correct significantly fewer of these (p < 0.001). Both ASPECTS levels were optimally covered in only 29% of the 16-row studies, whereas in the 64-row studies, both levels were invariably optimally visualized (p < 0.001). This significantly decreased the sensitivity of the 16-row scanner to detect perfusion defects in the upper ASPECTS level (p = 0.02). The 64-row scanner was able to detect more perfusion defects that were located entirely outside the ASPECTS regions (p = 0.03). There was no significant difference in the 3-month functional outcome. The 16-row scanner suffered from limited anatomic coverage that decreased the sensitivity to detect perfusion defects in the cranial parts of the middle cerebral artery region. The 16-row studies had poorer technical quality that was in part attributable to higher sampling frequency and smaller slice thickness making the imaging more sensitive to small-scale movement of the patient. (orig.)

  5. Growing cardiac hemangioma on serial F18 FDG PET/CT

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Young Jin; Yoon, Hyun Jin; Kang, Do Young [Dong A Univ. Medical Center, Busan (Korea, Republic of)

    2012-09-15

    Cardiac hemangiomas are extremely rare, benign tumors, which can occur anywhere in the heart. Symptoms are variable according to the size, extension and tumor location, but most cases are asymptomatic and are detected incidentally. They may grow, remain stable and regress; therefore, the natural course of the tumors is unpredictable. Diagnosis mainly depends upon echocardiography, CT, MRI and angiography. Reports of detection by F18 FDG PET/CT are very limited. We report a case of cardiac hemangioma attached to the right ventricle, compressing the ventricle. It was revealed incidentally on F18 FDG PET/CT for routine evaluation of thyroid cancer. During two serial F18 FDG PET/CTs, it grew from 2.8cm to 4.0cm with mild FDG uptake. After surgery, the patient remained stable without any complications.

  6. Subcutaneous Tissue Thickness is an Independent Predictor of Image Noise in Cardiac CT

    Energy Technology Data Exchange (ETDEWEB)

    Staniak, Henrique Lane; Sharovsky, Rodolfo [Hospital Universitário - Universidade de São Paulo, São Paulo, SP (Brazil); Pereira, Alexandre Costa [Hospital das Clínicas - Universidade de São Paulo, São Paulo, SP (Brazil); Castro, Cláudio Campi de; Benseñor, Isabela M.; Lotufo, Paulo A. [Hospital Universitário - Universidade de São Paulo, São Paulo, SP (Brazil); Faculdade de Medicina - Universidade de São Paulo, São Paulo, SP (Brazil); Bittencourt, Márcio Sommer, E-mail: msbittencourt@mail.harvard.edu [Hospital Universitário - Universidade de São Paulo, São Paulo, SP (Brazil)

    2014-01-15

    Few data on the definition of simple robust parameters to predict image noise in cardiac computed tomography (CT) exist. To evaluate the value of a simple measure of subcutaneous tissue as a predictor of image noise in cardiac CT. 86 patients underwent prospective ECG-gated coronary computed tomographic angiography (CTA) and coronary calcium scoring (CAC) with 120 kV and 150 mA. The image quality was objectively measured by the image noise in the aorta in the cardiac CTA, and low noise was defined as noise < 30HU. The chest anteroposterior diameter and lateral width, the image noise in the aorta and the skin-sternum (SS) thickness were measured as predictors of cardiac CTA noise. The association of the predictors and image noise was performed by using Pearson correlation. The mean radiation dose was 3.5 ± 1.5 mSv. The mean image noise in CT was 36.3 ± 8.5 HU, and the mean image noise in non-contrast scan was 17.7 ± 4.4 HU. All predictors were independently associated with cardiac CTA noise. The best predictors were SS thickness, with a correlation of 0.70 (p < 0.001), and noise in the non-contrast images, with a correlation of 0.73 (p < 0.001). When evaluating the ability to predict low image noise, the areas under the ROC curve for the non-contrast noise and for the SS thickness were 0.837 and 0.864, respectively. Both SS thickness and CAC noise are simple accurate predictors of cardiac CTA image noise. Those parameters can be incorporated in standard CT protocols to adequately adjust radiation exposure.

  7. First pass cable artefact correction for cardiac C-arm CT imaging.

    Science.gov (United States)

    Haase, C; Schäfer, D; Kim, M; Chen, S J; Carroll, J D; Eshuis, P; Dössel, O; Grass, M

    2014-07-21

    Cardiac C-arm CT imaging delivers a tomographic region-of-interest reconstruction of the patient's heart during image guided catheter interventions. Due to the limited size of the flat detector a volume image is reconstructed, which is truncated in the cone-beam (along the patient axis) and the fan-beam (in the transaxial plane) direction. To practically address this local tomography problem correction methods, like projection extension, are available for first pass image reconstruction. For second pass correction methods, like metal artefact reduction, alternative correction schemes are required when the field of view is limited to a region-of-interest of the patient. In classical CT imaging metal artefacts are corrected by metal identification in a first volume reconstruction and generation of a corrected projection data set followed by a second reconstruction. This approach fails when the metal structures are located outside the reconstruction field of view. When a C-arm CT is performed during a cardiac intervention pacing leads and other cables are frequently positioned on the patients skin, which results in propagating streak artefacts in the reconstruction volume. A first pass approach to reduce this type of artefact is introduced and evaluated here. It makes use of the fact that the projected position of objects outside the reconstruction volume changes with the projection perspective. It is shown that projection based identification, tracking and removal of high contrast structures like cables, only detected in a subset of the projections, delivers a more consistent reconstruction volume with reduced artefact level. The method is quantitatively evaluated based on 50 simulations using cardiac CT data sets with variable cable positioning. These data sets are forward projected using a C-arm CT system geometry and generate artefacts comparable to those observed in clinical cardiac C-arm CT acquisitions. A C-arm CT simulation of every cardiac CT data set without

  8. First pass cable artefact correction for cardiac C-arm CT imaging

    International Nuclear Information System (INIS)

    Cardiac C-arm CT imaging delivers a tomographic region-of-interest reconstruction of the patient's heart during image guided catheter interventions. Due to the limited size of the flat detector a volume image is reconstructed, which is truncated in the cone-beam (along the patient axis) and the fan-beam (in the transaxial plane) direction. To practically address this local tomography problem correction methods, like projection extension, are available for first pass image reconstruction. For second pass correction methods, like metal artefact reduction, alternative correction schemes are required when the field of view is limited to a region-of-interest of the patient. In classical CT imaging metal artefacts are corrected by metal identification in a first volume reconstruction and generation of a corrected projection data set followed by a second reconstruction. This approach fails when the metal structures are located outside the reconstruction field of view. When a C-arm CT is performed during a cardiac intervention pacing leads and other cables are frequently positioned on the patients skin, which results in propagating streak artefacts in the reconstruction volume. A first pass approach to reduce this type of artefact is introduced and evaluated here. It makes use of the fact that the projected position of objects outside the reconstruction volume changes with the projection perspective. It is shown that projection based identification, tracking and removal of high contrast structures like cables, only detected in a subset of the projections, delivers a more consistent reconstruction volume with reduced artefact level. The method is quantitatively evaluated based on 50 simulations using cardiac CT data sets with variable cable positioning. These data sets are forward projected using a C-arm CT system geometry and generate artefacts comparable to those observed in clinical cardiac C-arm CT acquisitions. A C-arm CT simulation of every cardiac CT data set

  9. Dynamic CT perfusion measurement in a cardiac phantom.

    Science.gov (United States)

    Ziemer, Benjamin P; Hubbard, Logan; Lipinski, Jerry; Molloi, Sabee

    2015-10-01

    Widespread clinical implementation of dynamic CT myocardial perfusion has been hampered by its limited accuracy and high radiation dose. The purpose of this study was to evaluate the accuracy and radiation dose reduction of a dynamic CT myocardial perfusion technique based on first pass analysis (FPA). To test the FPA technique, a pulsatile pump was used to generate known perfusion rates in a range of 0.96-2.49 mL/min/g. All the known perfusion rates were determined using an ultrasonic flow probe and the known mass of the perfusion volume. FPA and maximum slope model (MSM) perfusion rates were measured using volume scans acquired from a 320-slice CT scanner, and then compared to the known perfusion rates. The measured perfusion using FPA (P(FPA)), with two volume scans, and the maximum slope model (P(MSM)) were related to known perfusion (P(K)) by P(FPA) = 0.91P(K) + 0.06 (r = 0.98) and P(MSM) = 0.25P(K) - 0.02 (r = 0.96), respectively. The standard error of estimate for the FPA technique, using two volume scans, and the MSM was 0.14 and 0.30 mL/min/g, respectively. The estimated radiation dose required for the FPA technique with two volume scans and the MSM was 2.6 and 11.7-17.5 mSv, respectively. Therefore, the FPA technique can yield accurate perfusion measurements using as few as two volume scans, corresponding to approximately a factor of four reductions in radiation dose as compared with the currently available MSM. In conclusion, the results of the study indicate that the FPA technique can make accurate dynamic CT perfusion measurements over a range of clinically relevant perfusion rates, while substantially reducing radiation dose, as compared to currently available dynamic CT perfusion techniques.

  10. Whole-body low-dose multidetector row-CT in the diagnosis of multiple myeloma: an alternative to conventional radiography

    International Nuclear Information System (INIS)

    Objective: The goal of this study was to establish the feasibility of a low-dose whole-body multidetector row-CT (MDCT) protocol in the diagnosis of multiple myeloma (MM), as an alternative to conventional X-ray imaging, which is currently still state-of-the-art in these patients, with emphasis on the comparison of image resolution on axial and multiplanar reformatted (MPR) scans and reduction of radiation dose. Material and methods: 100 patients with known MM, or monoclonal gammopathy of unknown significance (MGUS) underwent unenhanced whole-body MDCT on a 16-slice scanner in a randomised fashion, using a 16 x 1.5 mm collimation and four different energy parameters (40, 50, 60 and 70 mAs). Three different reconstruction algorithms were used in every patient (B40f, B50f and B60f kernel). CT scans were reviewed independently by two radiologists, with regard to correct classification into one of the three known MM stages, and recognition of fracture risk. Thereafter, axial and MPR images were evaluated in consensus by both readers, with respect to image resolution. Diagnosis of osteolytic lesions was performed on the basis of axial and multiplanar reformatted images, whereas the assessment of spinal misalignment and fracture was done only on MPR images. The distribution of image resolution categories (very good, good, sufficient, insufficient for diagnosis) was evaluated depending on following parameters: current time product, patient's weight, bone density and reconstruction algorithm. The effective radiation dose was determined with the aid of an anthropomorphic Alderson Rando-Phantom, using a tube current time product of 40 mAs, and then extrapolating it on all current time products applied in this study on a commercially available software program WinDose (Institute of Medical Physics, Erlangen, Germany). Results: In all 100 patients, image resolution was diagnostic, regardless of scanning parameters, enabling correct classification of multiple myeloma patients

  11. Whole-body low-dose multidetector row-CT in the diagnosis of multiple myeloma: an alternative to conventional radiography

    Energy Technology Data Exchange (ETDEWEB)

    Horger, Marius; Claussen, Claus D.; Bross-Bach, Ulrike; Vonthein, Reinhard; Trabold, Tobias; Heuschmid, Martin; Pfannenberg, Christina

    2005-05-01

    Objective: The goal of this study was to establish the feasibility of a low-dose whole-body multidetector row-CT (MDCT) protocol in the diagnosis of multiple myeloma (MM), as an alternative to conventional X-ray imaging, which is currently still state-of-the-art in these patients, with emphasis on the comparison of image resolution on axial and multiplanar reformatted (MPR) scans and reduction of radiation dose. Material and methods: 100 patients with known MM, or monoclonal gammopathy of unknown significance (MGUS) underwent unenhanced whole-body MDCT on a 16-slice scanner in a randomised fashion, using a 16 x 1.5 mm collimation and four different energy parameters (40, 50, 60 and 70 mAs). Three different reconstruction algorithms were used in every patient (B40f, B50f and B60f kernel). CT scans were reviewed independently by two radiologists, with regard to correct classification into one of the three known MM stages, and recognition of fracture risk. Thereafter, axial and MPR images were evaluated in consensus by both readers, with respect to image resolution. Diagnosis of osteolytic lesions was performed on the basis of axial and multiplanar reformatted images, whereas the assessment of spinal misalignment and fracture was done only on MPR images. The distribution of image resolution categories (very good, good, sufficient, insufficient for diagnosis) was evaluated depending on following parameters: current time product, patient's weight, bone density and reconstruction algorithm. The effective radiation dose was determined with the aid of an anthropomorphic Alderson Rando-Phantom, using a tube current time product of 40 mAs, and then extrapolating it on all current time products applied in this study on a commercially available software program WinDose (Institute of Medical Physics, Erlangen, Germany). Results: In all 100 patients, image resolution was diagnostic, regardless of scanning parameters, enabling correct classification of multiple myeloma

  12. Cardiac spiral dual-source CT with high pitch: a feasibility study

    Energy Technology Data Exchange (ETDEWEB)

    Ertel, Dirk; Kalender, Willi A. [University of Erlangen-Nuernberg, Institute of Medical Physics (IMP), Erlangen (Germany); Lell, Michael M. [University of Erlangen-Nuernberg, Department of Radiology, Erlangen (Germany); Harig, Frank [University of Erlangen-Nuernberg, Center of Cardiac Surgery, Erlangen (Germany); Flohr, Thomas; Schmidt, Bernhard [Siemens Healthcare, Forchheim (Germany)

    2009-10-15

    Increase of pitch in spiral CT decreases data acquisition time; dual-source CT (DSCT) systems provide improved temporal resolution. We evaluated the combination of these two features. Measurements were performed using a commercial DSCT system equipped with prototype software allowing pitch factors from p=0.35 to 3.0. We measured slice sensitivity profiles as a function of pitch to assess spatial resolution in the z-direction and the contrast of structures moved periodically to measure temporal resolution. Additionally we derived modulation transfer functions to provide objective parameters; both spatial and temporal resolution were essentially unchanged even at high pitch. CT of the cardiac region of three pigs was performed at p=3.0. In vivo CT images confirmed good image quality; direct comparison with standard low-pitch phase-correlated CT image datasets showed no significant difference. For a normalized z-axis acquisition of 12 cm, the corresponding effective dose value was 2.0 mSv for the high-pitch CT protocol. We conclude that spiral DSCT imaging with a pitch of 3.0 can provide unimpaired image quality with respect to spatial and temporal resolution. Applications to cardiac and thoracic imaging with effective dose below 1 mSv are possible. (orig.)

  13. Evaluation of respiratory and cardiac motion correction schemes in dual gated PET/CT cardiac imaging

    Energy Technology Data Exchange (ETDEWEB)

    Lamare, F., E-mail: frederic.lamare@chu-bordeaux.fr; Fernandez, P. [Univ. Bordeaux, INCIA, UMR 5287, F-33400 Talence (France); CNRS, INCIA, UMR 5287, F-33400 Talence (France); Service de Médecine Nucléaire, Hôpital Pellegrin, CHU de Bordeaux, 33076 Bordeaux (France); Le Maitre, A.; Visvikis, D. [INSERM, UMR1101, LaTIM, Université de Bretagne Occidentale, 29609 Brest (France); Dawood, M.; Schäfers, K. P. [European Institute for Molecular Imaging, University of Münster, Mendelstr. 11, 48149 Münster (Germany); Rimoldi, O. E. [Vita-Salute University and Scientific Institute San Raffaele, Milan, Italy and CNR Istituto di Bioimmagini e Fisiologia Molecolare, Milan (Italy)

    2014-07-15

    Purpose: Cardiac imaging suffers from both respiratory and cardiac motion. One of the proposed solutions involves double gated acquisitions. Although such an approach may lead to both respiratory and cardiac motion compensation there are issues associated with (a) the combination of data from cardiac and respiratory motion bins, and (b) poor statistical quality images as a result of using only part of the acquired data. The main objective of this work was to evaluate different schemes of combining binned data in order to identify the best strategy to reconstruct motion free cardiac images from dual gated positron emission tomography (PET) acquisitions. Methods: A digital phantom study as well as seven human studies were used in this evaluation. PET data were acquired in list mode (LM). A real-time position management system and an electrocardiogram device were used to provide the respiratory and cardiac motion triggers registered within the LM file. Acquired data were subsequently binned considering four and six cardiac gates, or the diastole only in combination with eight respiratory amplitude gates. PET images were corrected for attenuation, but no randoms nor scatter corrections were included. Reconstructed images from each of the bins considered above were subsequently used in combination with an affine or an elastic registration algorithm to derive transformation parameters allowing the combination of all acquired data in a particular position in the cardiac and respiratory cycles. Images were assessed in terms of signal-to-noise ratio (SNR), contrast, image profile, coefficient-of-variation (COV), and relative difference of the recovered activity concentration. Results: Regardless of the considered motion compensation strategy, the nonrigid motion model performed better than the affine model, leading to higher SNR and contrast combined with a lower COV. Nevertheless, when compensating for respiration only, no statistically significant differences were

  14. Multi-detector CT perfusion

    Directory of Open Access Journals (Sweden)

    Ashraf M. Enite

    2016-09-01

    Conclusion: CTP is a promising non-invasive technique assessing the efficacy, predicting early response to local treatment therapies and monitoring tumor recurrence. It assesses the degree of post therapy tumor perfusion especially the degree of arterialization.

  15. 18F-NaF PET/CT Images of Cardiac Metastasis From Osteosarcoma.

    Science.gov (United States)

    Chou, Yi-Hsien; Ko, Kuan-Yin; Cheng, Mei-Fang; Chen, Wei-Wu; Yen, Ruoh-Fang

    2016-09-01

    Osteosarcomas are aggressive with a high incidence of recurrence and metastasis. Cardiac osteosarcoma metastasis is rare. We described a 17-year-old boy who had right distal femoral osteosarcoma with lung metastases. During follow-up, right ventricular (RV) metastasis was noted and confirmed by histopathological examination of the surgical specimen. F-NaF PET/CT was then arranged 1 month after debulking surgery for residual tumor survey. The images showed intense F-NaF uptake at RV region, suggestive of residual cardiac metastases. PMID:27405028

  16. Reduction of blooming artifacts in cardiac CT images by blind deconvolution and anisotropic diffusion filtering

    Science.gov (United States)

    Castillo-Amor, Angélica M.; Navarro-Navia, Cristian A.; Cadena-Bonfanti, Alberto J.; Contreras-Ortiz, Sonia H.

    2015-12-01

    Even though CT is an imaging technique that offers high quality images, limitations on its spatial resolution cause blurring in small objects with high contrast. This phenomenon is known as blooming artifact and affects cardiac images with small calcifications and stents. This paper describes an approach to reduce the blooming artifact and improve resolution in cardiac images using blind deconvolution and anisotropic diffusion filtering. Deconvolution increases resolution but reduces signal-to-noise ratio, and the anisotropic diffusion filter counteracts this effect without affecting the edges in the image.

  17. Performance comparison between static and dynamic cardiac CT on perfusion quantitation and patient classification tasks

    Science.gov (United States)

    Bindschadler, Michael; Modgil, Dimple; Branch, Kelley R.; La Riviere, Patrick J.; Alessio, Adam M.

    2015-03-01

    Cardiac CT acquisitions for perfusion assessment can be performed in a dynamic or static mode. In this simulation study, we evaluate the relative classification and quantification performance of these modes for assessing myocardial blood flow (MBF). In the dynamic method, a series of low dose cardiac CT acquisitions yields data on contrast bolus dynamics over time; these data are fit with a model to give a quantitative MBF estimate. In the static method, a single CT acquisition is obtained, and the relative CT numbers in the myocardium are used to infer perfusion states. The static method does not directly yield a quantitative estimate of MBF, but these estimates can be roughly approximated by introducing assumed linear relationships between CT number and MBF, consistent with the ways such images are typically visually interpreted. Data obtained by either method may be used for a variety of clinical tasks, including 1) stratifying patients into differing categories of ischemia and 2) using the quantitative MBF estimate directly to evaluate ischemic disease severity. Through simulations, we evaluate the performance on each of these tasks. The dynamic method has very low bias in MBF estimates, making it particularly suitable for quantitative estimation. At matched radiation dose levels, ROC analysis demonstrated that the static method, with its high bias but generally lower variance, has superior performance in stratifying patients, especially for larger patients.

  18. Principle and applications of dual source CT

    Science.gov (United States)

    Flohr, Thomas

    2008-08-01

    Dual source CT (DSCT) has the potential to solve remaining limitations of conventional multi-detector row CT (MDCT)-scanners, such as insufficient temporal resolution for ECG-controlled cardiac imaging. A DSCT is equipped with two X-ray tubes and two corresponding detectors that are mounted onto the rotating gantry with an angular offset of 90°. The key benefit of DSCT for cardiac scanning is improved temporal resolution equivalent to a quarter of the gantry rotation time (83 ms at 0.33 s rotation time). Additionally, both X-ray tubes can be operated at different kV- and mA-settings, enabling the acquisition of dual energy data. The acquisition of dual energy CT data can add functional information to the morphological information based on different X-ray attenuation coefficients that is usually obtained in a CT examination.

  19. 4D micro-CT for cardiac and perfusion applications with view under sampling

    Science.gov (United States)

    Badea, Cristian T.; Johnston, Samuel M.; Qi, Yi; Johnson, G. Allan

    2011-06-01

    Micro-CT is commonly used in preclinical studies to provide anatomical information. There is growing interest in obtaining functional measurements from 4D micro-CT. We report here strategies for 4D micro-CT with a focus on two applications: (i) cardiac imaging based on retrospective gating and (ii) pulmonary perfusion using multiple contrast injections/rotations paradigm. A dual source micro-CT system is used for image acquisition with a sampling rate of 20 projections per second. The cardiac micro-CT protocol involves the use of a liposomal blood pool contrast agent. Fast scanning of free breathing mice is achieved using retrospective gating. The ECG and respiratory signals are used to sort projections into ten cardiac phases. The pulmonary perfusion protocol uses a conventional contrast agent (Isovue 370) delivered by a micro-injector in four injections separated by 2 min intervals to allow for clearance. Each injection is synchronized with the rotation of the animal, and each of the four rotations is started with an angular offset of 22.5 from the starting angle of the previous rotation. Both cardiac and perfusion protocols result in an irregular angular distribution of projections that causes significant streaking artifacts in reconstructions when using traditional filtered backprojection (FBP) algorithms. The reconstruction involves the use of the point spread function of the micro-CT system for each time point, and the analysis of the distribution of the reconstructed data in the Fourier domain. This enables us to correct for angular inconsistencies via deconvolution and identify regions where data is missing. The missing regions are filled with data from a high quality but temporally averaged prior image reconstructed with all available projections. Simulations indicate that deconvolution successfully removes the streaking artifacts while preserving temporal information. 4D cardiac micro-CT in a mouse was performed with adequate image quality at isotropic

  20. Constrain static target kinetic iterative image reconstruction for 4D cardiac CT imaging

    Science.gov (United States)

    Alessio, Adam M.; La Riviere, Patrick J.

    2011-03-01

    Iterative image reconstruction offers improved signal to noise properties for CT imaging. A primary challenge with iterative methods is the substantial computation time. This computation time is even more prohibitive in 4D imaging applications, such as cardiac gated or dynamic acquisition sequences. In this work, we propose only updating the time-varying elements of a 4D image sequence while constraining the static elements to be fixed or slowly varying in time. We test the method with simulations of 4D acquisitions based on measured cardiac patient data from a) a retrospective cardiac-gated CT acquisition and b) a dynamic perfusion CT acquisition. We target the kinetic elements with one of two methods: 1) position a circular ROI on the heart, assuming area outside ROI is essentially static throughout imaging time; and 2) select varying elements from the coefficient of variation image formed from fast analytic reconstruction of all time frames. Targeted kinetic elements are updated with each iteration, while static elements remain fixed at initial image values formed from the reconstruction of data from all time frames. Results confirm that the computation time is proportional to the number of targeted elements; our simulations suggest that 3 times reductions in reconstruction time. The images reconstructed with the proposed method have matched mean square error with full 4D reconstruction. The proposed method is amenable to most optimization algorithms and offers the potential for significant computation improvements, which could be traded off for more sophisticated system models or penalty terms.

  1. Case series: CT scan in cardiac arrest and imminent cardiogenic shock

    International Nuclear Information System (INIS)

    Imaging a patient having a cardiac arrest on the examination table is not a common occurrence. Altered hemodynamics resulting from pump failure causes stasis of blood in the dependent organs of the body, which is manifested on imaging by dependent contrast pooling and layering. Often a patient with imminent cardiogenic shock also shows a similar dependent contrast pooling and layering, which is a marker of the worsening clinical condition. We report the contrast-enhanced CT scan features in four cases, two of whom had cardiac arrest during imaging, while the other two developed cardiogenic shock soon after the examination. Dependent contrast pooling and layering were found in all of them, with faint or no opacification of the left cardiac chambers. Contrast pooling was noted in the dependent lumbar veins, hepatic veins, hepatic parenchyma, and the right renal vein, as well as in the dependent part of the IVC and the right heart chambers

  2. Coronary CT angiography: automatic cardiac-phase selection for image reconstruction

    Energy Technology Data Exchange (ETDEWEB)

    Ruzsics, Balazs; Brothers, Robin L.; Costello, Philip [Medical University of South Carolina, Department of Radiology and Radiological Science, Charleston, SC (United States); Gebregziabher, Mulugeta [Medical University of South Carolina, Department of Biostatistics, Bioinformatics, and Epidemiology, Charleston, SC (United States); Lee, Heon [Medical University of South Carolina, Department of Radiology and Radiological Science, Charleston, SC (United States); Seoul Medical Center, Department of Radiology, Seoul (Korea); Allmendinger, Thomas; Vogt, Sebastian [Siemens Medical Solutions, Division CT, Forchheim (Germany); Schoepf, U.J. [Medical University of South Carolina, Department of Radiology and Radiological Science, Charleston, SC (United States); Medical University of South Carolina, Division of Cardiology, Charleston, SC (United States)

    2009-08-15

    We evaluated an algorithm for automatic selection of the cardiac phase with the least motion for image reconstruction at coronary computed tomography (CT) angiography (CCTA). We analyzed data of 100 patients (49 female, mean age 59 years) who had undergone retrospectively ECG-gated CCTA. Two experienced observers visually identified the most suitable end-systolic and end-diastolic phases using a series of image reconstructions in 5% increments across the RR cycle. The same data were then reconstructed using an automatic phase finding algorithm based on a 4D weighting function of cardiac motion. On average, the algorithm determined the most suitable systolic reconstruction phase at 40.11{+-}6.29% RR compared with 40.07{+-}5.58% RR by the human observers (p=NS). The most suitable diastolic phase was found at 72.71{+-}7.37% RR by the automatic algorithm, compared with 76.43{+-}6.35% RR by the observers (p<0.05). No statistically significant difference was found between automatically and visually determined reconstruction phases regarding motion and stair-step artifacts in either systole or diastole (p>0.05). Thus, there appears to be no relevant difference between an automatic phase finding algorithm and visual selection by experienced observers for determining the phase with the least cardiac motion for CCTA image reconstruction. The use of automatic phase finding may therefore facilitate the performance of cardiac CT and reduce human error. (orig.)

  3. Spiral CT of Non-Graft Post Cardiac Surgery Complications: A Pictorial Essay

    Directory of Open Access Journals (Sweden)

    S. Shirani

    2010-06-01

    Full Text Available Spiral CT is a rapidly growing method for noninvasive visualization of post-operative complications, including post-operative complications in CABG (coronary artery bypass graft. In the recent years, several different, yet more efficient types have been introduced with progressive improvement in the diagnostic accuracy in the detection of post-operative complications. The introduction of 64-slice technology, which allows high resolution as well as reconstructed images, has resulted in further progress in the diagnostic process. This kind of diagnostic equipment will spread rapidly in the world. Although studies with large numbers of patients regarding spiral CT as a routine diagnostic method have not been reported, there is great need for it all over the world. In this article, we intend to review the spiral CT findings of non-graft complications in patients after cardiac surgery.

  4. Feasibility of epicardial adipose tissue quantification in non-ECG-gated low-radiation-dose CT: comparison with prospectively ECG-gated cardiac CT

    Energy Technology Data Exchange (ETDEWEB)

    Simon-Yarza, Isabel; Viteri-Ramirez, Guillermo; Saiz-Mendiguren, Ramon; Slon-Roblero, Pedro J.; Paramo, Maria [Dept. of Radiology, Clinica Univ. de Navarra, Pamplona (Spain); Bastarrika, Gorka [Dept. of Radiology, Clinica Univ. de Navarra, Pamplona (Spain); Cardiac Imaging Unit, Clinica Univ. de Navarra, Pamplona (Spain)], e-mail: bastarrika@unav.es

    2012-06-15

    Background: Epicardial adipose tissue (EAT) is an important indicator of cardiovascular risk. This parameter is generally assessed on ECG-gated computed tomography (CT) images. Purpose: To evaluate feasibility and reliability of EAT quantification on non-gated thoracic low-radiation-dose CT examinations with respect to prospectively ECG-gated cardiac CT acquisition. Material and Methods: Sixty consecutive asymptomatic smokers (47 men; mean age 64 {+-} 9.8 years) underwent low-dose CT of the chest and prospectively ECG-gated cardiac CT acquisitions (64-slice dual-source CT). The two examinations were reconstructed with the same range, field of view, slice thickness, and convolution algorithm. Two independent observers blindly quantified EAT volume using commercially available software. Data were compared with paired sample Student t-test, concordance correlation coefficients (CCC), and Bland-Altman plots. Results: No statistically significant difference was observed for EAT volume quantification with low-dose-CT (141.7 {+-} 58.3 mL) with respect to ECG-gated CT (142.7 {+-} 57.9 mL). Estimation of CCC showed almost perfect concordance between the two techniques for EAT-volume assessment (CCC, 0.99; mean difference, 0.98 {+-} 5.1 mL). Inter-observer agreement for EAT volume estimation was CCC: 0.96 for low-dose-CT examinations and 0.95 for ECG-gated CT. Conclusion: Non-gated low-dose CT allows quantifying EAT with almost the same concordance and reliability as using dedicated prospectively ECG-gated cardiac CT acquisition protocols.

  5. Cardiac CT angiography after coronary artery surgery in children using 64-slice CT scan

    Energy Technology Data Exchange (ETDEWEB)

    Marini, Davide; Agnoletti, Gabriella [Centre de Reference Malformations Cardiaques Congenitales Complexes-M3C, Universite Paris Descartes, UFR Necker-Enfants Malades, Paris (France); Brunelle, Francis [University Paris Descartes, UFR Necker-Enfants Malades, Department of Pediatric Radiology, APHP, Paris (France); Sidi, Daniel; Bonnet, Damien [Centre de Reference Malformations Cardiaques Congenitales Complexes-M3C, Universite Paris Descartes, UFR Necker-Enfants Malades, Paris (France); Ou, Phalla [Centre de Reference Malformations Cardiaques Congenitales Complexes-M3C, Universite Paris Descartes, UFR Necker-Enfants Malades, Paris (France); University Paris Descartes, UFR Necker-Enfants Malades, Department of Pediatric Radiology, APHP, Paris (France)], E-mail: phalla.ou@nck.aphp.fr

    2009-09-15

    Objective: The purpose of this study was to compare the diagnostic accuracy of 64-slice CT with that of invasive angiography in the detection of graft and/or coronary angioplasty stenosis in children who had undergone coronary artery surgery. Population and methods: Fifteen consecutive children (8 male and 7 female; age 9.2 {+-} 6.1 years) underwent 64-slice CT because of chest pain or ECG changes mean 4.8 {+-} 3.7 years after surgical coronary artery surgery; 10 patients had coronary angioplasty using a patch from the saphenous vein, four had mammary artery bypass, and one had saphenous vein bypass. Six main segments of the coronary arteries and all the bypass graft considered as a single segment were analyzed and compared with invasive angiography used as the reference standard. Results: CT correctly identified the four children with coronary angioplasty and mammary graft lesions that were confirmed by conventional angiography: one patient had a significant stenosis (>50% stenosis) at the mammary bypass graft anastomosis site; three other had non-significant stenosis (<50% stenosis) including a mild lesion of the saphenous vein patch in two patients and a mild lesion at the anastomosis site of the mammary bypass in one. All segments identified as normal by CT in the other 11 children were also found to be normal by conventional angiography. Conclusion: In centers expert in this technique, 64-slice CT scanning is a promising, rapid, and useful diagnostic technique for evaluating both coronary angioplasty and bypass graft lesions in children who had undergone coronary artery surge0008.

  6. Image registration and analysis for quantitative myocardial perfusion: application to dynamic circular cardiac CT

    Science.gov (United States)

    Isola, A. A.; Schmitt, H.; van Stevendaal, U.; Begemann, P. G.; Coulon, P.; Boussel, L.; Grass, M.

    2011-09-01

    Large area detector computed tomography systems with fast rotating gantries enable volumetric dynamic cardiac perfusion studies. Prospectively, ECG-triggered acquisitions limit the data acquisition to a predefined cardiac phase and thereby reduce x-ray dose and limit motion artefacts. Even in the case of highly accurate prospective triggering and stable heart rate, spatial misalignment of the cardiac volumes acquired and reconstructed per cardiac cycle may occur due to small motion pattern variations from cycle to cycle. These misalignments reduce the accuracy of the quantitative analysis of myocardial perfusion parameters on a per voxel basis. An image-based solution to this problem is elastic 3D image registration of dynamic volume sequences with variable contrast, as it is introduced in this contribution. After circular cone-beam CT reconstruction of cardiac volumes covering large areas of the myocardial tissue, the complete series is aligned with respect to a chosen reference volume. The results of the registration process and the perfusion analysis with and without registration are evaluated quantitatively in this paper. The spatial alignment leads to improved quantification of myocardial perfusion for three different pig data sets.

  7. Multidetector Computed Tomography in Acute Joint Fractures

    Energy Technology Data Exchange (ETDEWEB)

    Haapamaeki, V.V.; Kiuru, M.J.; Mustonen, A.O.; Koskinen, S.K. [Helsinki Univ. Central Hospital (Finland). Helsinki Medical Imaging Center

    2005-10-01

    Conventional radiography plays an essential diagnostic role in the primary evaluation of acute joint trauma. In complex fractures, however, computed tomography (CT) is an imaging modality often used second to radiography. As a result of technical breakthroughs in the field, multidetector CT (MDCT) allows faster imaging and better temporal, spatial, and contrast resolution compared with conventional single-slice spiral CT. MDCT with multiplanar reformation is helpful in disclosing fracture patterns, particularly in complex joint fractures, where they reveal occult fractures and show the exact number of fracture components and their degree of displacement.

  8. Survey regarding the clinical practice of cardiac CT in Germany. Indications, scanning technique and reporting

    Energy Technology Data Exchange (ETDEWEB)

    Maurer, Marc H.; Hamm, B.; Dewey, M. [Inst. fuer Radiologie, Charite - Universitaetsmedizin Berlin (Germany)

    2009-12-15

    Purpose: to obtain an overview of the current clinical practice of cardiac computed tomography (CT) in Germany. Materials and methods: a 30-item question-naire was mailed to 149 providers of cardiac CT in Germany. The items asked about indications, scanning technique and reporting, data storage, and cost of the examination. Results: overall 45 questionnaires could be analyzed (30%). The majority of centers (76%, 34 of 45 centers) used CT scanners of the latest generation (at least 64 rows). The most common appropriate indications were exclusion of coronary artery disease (91%, 41/45), coronary anomalies (80%, 36/45), and follow-up after coronary artery bypass grafting (53%, 24/45). Each center examined on average 243 {+-} 310 patients in 2007 and the number of centers performing cardiac CT increased significantly in 2007 (p = 0.035) compared with the preceding year. Most used sublingual nitroglycerin (84%, 38/45; median of 2 sprays = 0.8 mg) and/or a beta blocker (86%, 39/44; median of 5 mg IV, median heart rate threshold: 70 beats/min). Many providers used ECG-triggered tube current modulation (65%, 29/44) and/or adjusted the tube current to the body mass index or body weight (63%, 28/44). A median slice thickness of 0.75 mm with a 0.5 mm increment and a 20 cm field-of-view was most commonly used. Source images in orthogonal planes (96%, 43/45), curved MPRs (93%, 42/45), and thin-slice MIPs (69%, 31/45) were used most frequently for interpretation. Extracardiac structures were also evaluated by 84% of the centers (38/45). The mean examination time was 16.2 min and reporting took an average of 28.8 min. (orig.)

  9. Assessment of phase based dose modulation for improved dose efficiency in cardiac CT on an anthropomorphic motion phantom

    Science.gov (United States)

    Budde, Adam; Nilsen, Roy; Nett, Brian

    2014-03-01

    State of the art automatic exposure control modulates the tube current across view angle and Z based on patient anatomy for use in axial full scan reconstructions. Cardiac CT, however, uses a fundamentally different image reconstruction that applies a temporal weighting to reduce motion artifacts. This paper describes a phase based mA modulation that goes beyond axial and ECG modulation; it uses knowledge of the temporal view weighting applied within the reconstruction algorithm to improve dose efficiency in cardiac CT scanning. Using physical phantoms and synthetic noise emulation, we measure how knowledge of sinogram temporal weighting and the prescribed cardiac phase can be used to improve dose efficiency. First, we validated that a synthetic CT noise emulation method produced realistic image noise. Next, we used the CT noise emulation method to simulate mA modulation on scans of a physical anthropomorphic phantom where a motion profile corresponding to a heart rate of 60 beats per minute was used. The CT noise emulation method matched noise to lower dose scans across the image within 1.5% relative error. Using this noise emulation method to simulate modulating the mA while keeping the total dose constant, the image variance was reduced by an average of 11.9% on a scan with 50 msec padding, demonstrating improved dose efficiency. Radiation dose reduction in cardiac CT can be achieved while maintaining the same level of image noise through phase based dose modulation that incorporates knowledge of the cardiac reconstruction algorithm.

  10. Infant Cardiac CT Angiography with 64-Slice and 256-Slice CT: Comparison of Radiation Dose and Image Quality Using a Pediatric Phantom

    OpenAIRE

    Lee, Yi-Wei; Yang, Ching-Ching; Mok, Greta S. P.; Wu, Tung-Hsin

    2012-01-01

    Background The aims of this study were to investigate the image quality and radiation exposure of pediatric protocols for cardiac CT angiography (CTA) in infants under one year of age. Methodology/Principal Findings Cardiac CTA examinations were performed using an anthropomorphic phantom representing a 1-year-old child scanned with non-electrocardiogram-gated (NG), retrospectively electrocardiogram-gated helical (RGH) and prospectively electrocardiogram-gated axial (PGA) techniques in 64-slic...

  11. Feasibility of determining myocardial transient ischemic dilation from cardiac CT by automated stress/rest registration

    Science.gov (United States)

    Woo, Jonghye; Slomka, Piotr J.; Nakazato, Ryo; Tamarappoo, Balaji K.; Min, James K.; Germano, Guido; Berman, Daniel S.; Dey, Damini

    2012-02-01

    Transient ischemic dilation (TID) of the left ventricle measured by myocardial perfusion Single Photon Emission Computed Tomography (SPECT) and defined as a the ratio of stress myocardial blood volume to rest myocardial blood volume has been shown to be highly specific for detection of severe coronary artery disease. This work investigates automated quantification of TID from cardiac Computed Tomography (CT) perfusion images. To date, TID has not been computed from CT. Previous studies to compute TID have assumed accurate segmentation of the left ventricle and performed subsequent analysis of volume change mainly on static or less often on gated myocardial perfusion SPECT. This, however, may limit the accuracy of TID due to potential errors from segmentation, perfusion defects or volume measurement from both images. In this study, we propose to use registration methods to determine TID from cardiac CT scans where deformation field within the structure of interest is used to measure the local volume change between stress and rest. Promising results have been demonstrated with 7 datasets, showing the potential of this approach as a comparative method for measuring TID.

  12. Analysis of Heart Rate and Heart Rate Variation During Cardiac CT Examinations

    Science.gov (United States)

    Zhang, Jie; Fletcher, Joel G.; Harmsen, W. Scott; Araoz, Philip A.; Williamson, Eric E.; Primak, Andrew N.; McCollough, Cynthia H.

    2009-01-01

    Rationale and Objectives We sought to examine heart rate and heart rate variability during cardiac computed tomography (CT). Materials and Methods Ninety patients (59.0 ± 13.5 years) underwent coronary CT angiography (CTA), with 52 patients also undergoing coronary artery calcium scanning (CAC). Forty-two patients with heart rate greater than 70 bpm were pretreated with oral β-blockers (in five patients, use of β-blocker was not known). Sixty-four patients were given sublingual nitroglycerin. Mean heart rate and percentage of beats outside a ±5 bpm region about the mean were compared between baseline (free breathing), prescan hyperventilation, and scan acquisition (breath-hold). Results Mean scan acquisition time was 13.1 ± 1.5 seconds for CAC scanning and 14.2 ± 2.9 seconds for coronary CTA. Mean heart rate during scan acquisition was significantly lower than at baseline (CAC 58.2 ± 8.5 bpm; CTA 59.2 ± 8.8 bpm; baseline 62.8 ± 8.9 bpm; P .05). Conclusions Breath-holding during cardiac CT scan acquisition significantly lowers the mean heart rate by approximately 4 bpm, but heart rate variability is the same or less compared with normal breathing. PMID:18078905

  13. Influence of technical parameters on epicardial fat volume quantification at cardiac CT

    Energy Technology Data Exchange (ETDEWEB)

    Bucher, Andreas M. [Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Department of Diagnostic and Interventional Radiology, Clinic of the Goethe University, Frankfurt (Germany); Joseph Schoepf, U., E-mail: schoepf@musc.edu [Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Division of Cardiology, Department of Medicine, Medical University of South Carolina, Charleston, SC (United States); Krazinski, Aleksander W.; Silverman, Justin; Spearman, James V. [Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); De Cecco, Carlo N. [Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Department of Radiological Sciences, Oncology and Pathology, University of Rome “Sapienza” – Polo Pontino, Latina (Italy); Meinel, Felix G. [Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Institute for Clinical Radiology, Ludwig-Maximilians-University Hospital, Munich (Germany); Vogl, Thomas J. [Department of Diagnostic and Interventional Radiology, Clinic of the Goethe University, Frankfurt (Germany); Geyer, Lucas L. [Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Institute for Clinical Radiology, Ludwig-Maximilians-University Hospital, Munich (Germany)

    2015-06-15

    Highlights: • Upper threshold levels and contrast enhancement influence epicardial fat volumetry. • Cardiac cycle does not significantly influence epicardial fat volumetry. • Adjustments of upper threshold can lead to comparable volumetry results. - Abstract: Objectives: To systematically analyze the influence of technical parameters on quantification of epicardial fat volume (EATV) at cardiac CT. Methods: 153 routine cardiac CT data sets were analyzed using three-dimensional pericardial border delineation. Three image series were reconstructed per patient: (a) CTA{sub D}: coronary CT angiography (CTA), diastolic phase; (b) CTA{sub S}: coronary CTA, systolic phase; (c) CaSc{sub D}: non-contrast CT, diastolic phase. EATV was calculated using three different upper thresholds (−15HU, −30HU, −45HU). Repeated measures ANOVA, Spearman's rho, and Bland Altman plots were used. Results: Mean EATV differed between all three image series at a −30HU threshold (CTA{sub D} 87.2 ± 38.5 ml, CTA{sub S} 90.9 ± 37.7 ml, CaSc{sub D} 130.7 ± 49.5 ml, P < 0.001). EATV of diastolic and systolic CTA reconstructions did not differ significantly (P = 0.225). Mean EATV for contrast enhanced CTA at a −15HU threshold (CTA{sub D15} 102.4 ± 43.6 ml, CTA{sub S15} 105.3 ± 42.3 ml) could be approximated most closely by non-contrast CT at −45HU threshold (CaSc{sub D45} 105.3 ± 40.8 ml). The correlation was excellent: CTA{sub S15}–CTA{sub D15}, rho = 0.943; CTA{sub D15}–CaSc{sub D45}, rho = 0.905; CTA{sub S15}–CaSc{sub D45}, rho = 0.924; each P < 0.001). Bias values from Bland Altman Analysis were: CTA{sub S15}–CTA{sub D15}, 4.9%; CTA{sub D15}–CaSc{sub D45}, −4.3%; CTA{sub S15}–CaSc{sub D45}, 0.6%. Conclusions: Measured EATV can differ substantially between contrast enhanced and non-contrast CT studies, which can be reconciled by threshold modification. Heart cycle phase does not significantly influence EATV measurements.

  14. Automatic intrinsic cardiac and respiratory gating from cone-beam CT scans of the thorax region

    Science.gov (United States)

    Hahn, Andreas; Sauppe, Sebastian; Lell, Michael; Kachelrieß, Marc

    2016-03-01

    We present a new algorithm that allows for raw data-based automated cardiac and respiratory intrinsic gating in cone-beam CT scans. It can be summarized in three steps: First, a median filter is applied to an initially reconstructed volume. The forward projection of this volume contains less motion information and is subtracted from the original projections. This results in new raw data that contain only moving and not static anatomy like bones, that would otherwise impede the cardiac or respiratory signal acquisition. All further steps are applied to these modified raw data. Second, the raw data are cropped to a region of interest (ROI). The ROI in the raw data is determined by the forward projection of a binary volume of interest (VOI) that includes the diaphragm for respiratory gating and most of the edge of the heart for cardiac gating. Third, the mean gray value in this ROI is calculated for every projection and the respiratory/cardiac signal is acquired using a bandpass filter. Steps two and three are carried out simultaneously for 64 or 1440 overlapping VOI inside the body for the respiratory or cardiac signal respectively. The signals acquired from each ROI are compared and the most consistent one is chosen as the desired cardiac or respiratory motion signal. Consistency is assessed by the standard deviation of the time between two maxima. The robustness and efficiency of the method is evaluated using simulated and measured patient data by computing the standard deviation of the mean signal difference between the ground truth and the intrinsic signal.

  15. Accessory left atrial diverticulae: contractile properties depicted with 64-slice cine-cardiac CT.

    LENUS (Irish Health Repository)

    Killeen, Ronan P

    2012-02-01

    To assess the contractility of accessory left atrial appendages (LAAs) using multiphasic cardiac CT. We retrospectively analyzed the presence, location, size and contractile properties of accessory LAAs using multiphasic cardiac 64-slice CT in 102 consecutive patients (63 males, 39 females, mean age 57). Multiplanar reformats were used to create image planes in axial oblique, sagittal oblique and coronal oblique planes. For all appendages with an orifice diameter >or= 10 mm, axial and sagittal diameters and appendage volumes were recorded in atrial diastole and systole. Regression analysis was performed to assess which imaging appearances best predicted accessory appendage contractility. Twenty-three (23%) patients demonstrated an accessory LAA, all identified along the anterior LA wall. Dimensions for axial oblique (AOD) and sagittal oblique (SOD) diameters and sagittal oblique length (SOL) were 6.3-19, 3.4-20 and 5-21 mm, respectively. All appendages (>or=10 mm) demonstrated significant contraction during atrial systole (greatest diameter reduction was AOD [3.8 mm, 27%]). Significant correlations were noted between AOD-contraction and AOD (R = 0.57, P < 0.05) and SOD-contraction and AOD, SOD and SOL (R = 0.6, P < 0.05). Mean diverticulum volume in atrial diastole was 468.4 +\\/- 493 mm(3) and in systole was 171.2 +\\/- 122 mm(3), indicating a mean change in volume of 297.2 +\\/- 390 mm(3), P < 0.0001. Stepwise multiple regression analysis revealed SOL to be the strongest independent predictor of appendage contractility (R(2) = 0.86, P < 0.0001) followed by SOD (R(2) = 0.91, P < 0.0001). Accessory LAAs show significant contractile properties on cardiac CT. Those accessory LAAs with a large sagittal height or depth should be evaluated for contractile properties, and if present should be examined for ectopic activity during electrophysiological studies.

  16. Radiation Dose to the Thyroid and Gonads in Patients Undergoing Cardiac CT Angiography

    International Nuclear Information System (INIS)

    The present data show a global increase in the rate of cardiovascular disease. Cardiac CT angiography has developed as a fast and non-invasive cardiac imaging modality following the introduction of multi-slice computed tomogaraphy. The aim of this study was to measure the radiation dose to the thyroid and pelvis regions in patients undergoing cardiac CT angiography using the Care Dose 4D method of 64-slice scanner. Eighty-one patients (41 males and 40 females) who were diagnosed with suspected coronary artery disease and were referred to Golestan Hospital, Imaging Department were recruited. Inclusion criteria were based on the protocol of multi-slice CT coronary angiography. The radiation dose to the thyroid and pelvis regions was measured using thermo luminescent dosimeters (TLDs). The mean radiation dose to the thyroid in male and female subjects was 0.32 mSv and 0.41 mSv, respectively (P = 0.032) (total mean, 0.36 mSv). The mean radiation dose to the pelvis in male and female subjects was 81 μSv and 112 μSv, respectively (P = 0.026) (total mean, 96.5 μSv), The total mean radiation dose to the thyroid and gonads was 0.36 mSv, and 96.5 μSv, respectively for the subjects. These values were high for one organ in a single study. Gender can affect the radiation dose to the thyroid and gonads. This can be attributed to the anatomical characteristic differences of the male and female subjects

  17. Improving best-phase image quality in cardiac CT by motion correction with MAM optimization

    International Nuclear Information System (INIS)

    Purpose: Research in image reconstruction for cardiac CT aims at using motion correction algorithms to improve the image quality of the coronary arteries. The key to those algorithms is motion estimation, which is currently based on 3-D/3-D registration to align the structures of interest in images acquired in multiple heart phases. The need for an extended scan data range covering several heart phases is critical in terms of radiation dose to the patient and limits the clinical potential of the method. Furthermore, literature reports only slight quality improvements of the motion corrected images when compared to the most quiet phase (best-phase) that was actually used for motion estimation. In this paper a motion estimation algorithm is proposed which does not require an extended scan range but works with a short scan data interval, and which markedly improves the best-phase image quality. Methods: Motion estimation is based on the definition of motion artifact metrics (MAM) to quantify motion artifacts in a 3-D reconstructed image volume. The authors use two different MAMs, entropy, and positivity. By adjusting the motion field parameters, the MAM of the resulting motion-compensated reconstruction is optimized using a gradient descent procedure. In this way motion artifacts are minimized. For a fast and practical implementation, only analytical methods are used for motion estimation and compensation. Both the MAM-optimization and a 3-D/3-D registration-based motion estimation algorithm were investigated by means of a computer-simulated vessel with a cardiac motion profile. Image quality was evaluated using normalized cross-correlation (NCC) with the ground truth template and root-mean-square deviation (RMSD). Four coronary CT angiography patient cases were reconstructed to evaluate the clinical performance of the proposed method. Results: For the MAM-approach, the best-phase image quality could be improved for all investigated heart phases, with a maximum

  18. Improving best-phase image quality in cardiac CT by motion correction with MAM optimization

    Energy Technology Data Exchange (ETDEWEB)

    Rohkohl, Christopher; Bruder, Herbert; Stierstorfer, Karl [Siemens AG, Healthcare Sector, Siemensstrasse 1, 91301 Forchheim (Germany); Flohr, Thomas [Siemens AG, Healthcare Sector, Siemensstrasse 1, 91301 Forchheim (Germany); Institute of Diagnostic Radiology, Eberhard Karls University, Hoppe-Seyler-Str. 3, 72076 Tuebingen (Germany)

    2013-03-15

    Purpose: Research in image reconstruction for cardiac CT aims at using motion correction algorithms to improve the image quality of the coronary arteries. The key to those algorithms is motion estimation, which is currently based on 3-D/3-D registration to align the structures of interest in images acquired in multiple heart phases. The need for an extended scan data range covering several heart phases is critical in terms of radiation dose to the patient and limits the clinical potential of the method. Furthermore, literature reports only slight quality improvements of the motion corrected images when compared to the most quiet phase (best-phase) that was actually used for motion estimation. In this paper a motion estimation algorithm is proposed which does not require an extended scan range but works with a short scan data interval, and which markedly improves the best-phase image quality. Methods: Motion estimation is based on the definition of motion artifact metrics (MAM) to quantify motion artifacts in a 3-D reconstructed image volume. The authors use two different MAMs, entropy, and positivity. By adjusting the motion field parameters, the MAM of the resulting motion-compensated reconstruction is optimized using a gradient descent procedure. In this way motion artifacts are minimized. For a fast and practical implementation, only analytical methods are used for motion estimation and compensation. Both the MAM-optimization and a 3-D/3-D registration-based motion estimation algorithm were investigated by means of a computer-simulated vessel with a cardiac motion profile. Image quality was evaluated using normalized cross-correlation (NCC) with the ground truth template and root-mean-square deviation (RMSD). Four coronary CT angiography patient cases were reconstructed to evaluate the clinical performance of the proposed method. Results: For the MAM-approach, the best-phase image quality could be improved for all investigated heart phases, with a maximum

  19. The effects of gantry tilt on breast dose and image noise in cardiac CT

    Energy Technology Data Exchange (ETDEWEB)

    Hoppe, Michael E.; Gandhi, Diksha; Schmidt, Taly Gilat [Department of Biomedical Engineering, Marquette University, Milwaukee, Wisconsin 53233 (United States); Stevens, Grant M. [GE Healthcare, Waukesha, Wisconsin 53188 (United States); Foley, W. Dennis [Department of Radiology, Medical College of Wisconsin, Froedtert Memorial Lutheran Hospital, Milwaukee, Wisconsin 53226 (United States)

    2013-12-15

    Purpose: This study investigated the effects of tilted-gantry acquisition on image noise and glandular breast dose in females during cardiac computed tomography (CT) scans. Reducing the dose to glandular breast tissue is important due to its high radiosensitivity and limited diagnostic significance in cardiac CT scans.Methods: Tilted-gantry acquisition was investigated through computer simulations and experimental measurements. Upon IRB approval, eight voxelized phantoms were constructed from previously acquired cardiac CT datasets. Monte Carlo simulations quantified the dose deposited in glandular breast tissue over a range of tilt angles. The effects of tilted-gantry acquisition on breast dose were measured on a clinical CT scanner (CT750HD, GE Healthcare) using an anthropomorphic phantom with MOSFET dosimeters in the breast regions. In both simulations and experiments, scans were performed at gantry tilt angles of 0°–30°, in 5° increments. The percent change in breast dose was calculated relative to the nontilted scan for all tilt angles. The percent change in noise standard deviation due to gantry tilt was calculated in all reconstructed simulated and experimental images.Results: Tilting the gantry reduced the breast dose in all simulated and experimental phantoms, with generally greater dose reduction at increased gantry tilts. For example, at 30° gantry tilt, the dosimeters located in the superior, middle, and inferior breast regions measured dose reductions of 74%, 61%, and 9%, respectively. The simulations estimated 0%–30% total breast dose reduction across the eight phantoms and range of tilt angles. However, tilted-gantry acquisition also increased the noise standard deviation in the simulated phantoms by 2%–50% due to increased pathlength through the iodine-filled heart. The experimental phantom, which did not contain iodine in the blood, demonstrated decreased breast dose and decreased noise at all gantry tilt angles.Conclusions: Tilting the

  20. 64排螺旋CT灌注成像对前列腺癌的诊断价值研究%Study on Diagnostic Value of 64 - multidetector Spiral CT Perfusion Imaging in Prostate Carcinoma

    Institute of Scientific and Technical Information of China (English)

    殷少龙; 许庆森; 赵春龙; 武迎军; 冯庆韬

    2012-01-01

    目的 探讨64排螺旋CT灌注成像对前列腺癌(PCa)的诊断价值. 方法 选择2006年8月-2010年5月张家口市第一医院确诊的前列腺癌患者62例,另选择正常前列腺15例为对照组.两组均行64排螺旋CT灌注成像技术检查,对比两组灌注参数之间的差异. 结果 对照组正常前列腺中央带和周围带的CT灌注参数比较,中央带明显高于周围带(P<0.05).正常对照组(周围带)和PCa组的CT灌注参数比较,PCa组的BF、BV、PS明显高于对照组(周围带)(P<0.05),MTT、TTP值明显小于对照组(周围带)(P<0.05).对照组TDC曲线呈缓升-平台型,PCa组TDC曲线呈速升-缓降型. 结论 64排螺旋CT灌注成像对PCa具有重要的诊断价值,其中BF、PS、TTP对PCa的评价意义最大,能更准确反映肿瘤的血管生成,可以作为临床诊断PCa的有效普查方法.%Objective To explore the value of 54 - multidetector spiral CT perfusion imaging in diagnosis of prostate carcinoma (PCa). Methods Sixty- two patients with PCa confirmed by the First Hospital of Zhangjiakou City from August 2006 to May 2010 were selected as PCa group, and another 15 healthy individuals were served as the control group. 64 - multidetector spiral CT perfusion imaging was performed on all objects of the study. The differences in the perfusion parameters of the two groups, including mean blood flow (BF), blood volume (BV), time to peak (TTP), mean transit time (MTT), capillary permeability - surface (PS), time-density curve (TDC) were documented and compared. Results In the control group, the perfusion parameters of the central zone were significantly higher than those in the peripheral zone (P < 0.05). Compared with the perfusion parameters of the peripheral zone of the control group, BF, BV and PS of Pca group were significantly higher than those in the control group (P<0.05), while TTP and MTT were significantly less than those in the control group (P< 0.05). Time - density curve of the

  1. 3D cardiac motion reconstruction from CT data and tagged MRI.

    Science.gov (United States)

    Wang, Xiaoxu; Mihalef, Viorel; Qian, Zhen; Voros, Szilard; Metaxas, Dimitris

    2012-01-01

    In this paper we present a novel method for left ventricle (LV) endocardium motion reconstruction using high resolution CT data and tagged MRI. High resolution CT data provide anatomic details on the LV endocardial surface, such as the papillary muscle and trabeculae carneae. Tagged MRI provides better time resolution. The combination of these two imaging techniques can give us better understanding on left ventricle motion. The high resolution CT images are segmented with mean shift method and generate the LV endocardium mesh. The meshless deformable model built with high resolution endocardium surface from CT data fit to the tagged MRI of the same phase. 3D deformation of the myocardium is computed with the Lagrangian dynamics and local Laplacian deformation. The segmented inner surface of left ventricle is compared with the heart inner surface picture and show high agreement. The papillary muscles are attached to the inner surface with roots. The free wall of the left ventricle inner surface is covered with trabeculae carneae. The deformation of the heart wall and the papillary muscle in the first half of the cardiac cycle is presented. The motion reconstruction results are very close to the live heart video. PMID:23366825

  2. Assessing Cardiac Injury in Mice With Dual Energy-MicroCT, 4D-MicroCT, and MicroSPECT Imaging After Partial Heart Irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Chang-Lung; Min, Hooney [Department of Radiation Oncology, Duke University Medical Center, Durham, North Carolina (United States); Befera, Nicholas; Clark, Darin; Qi, Yi [Center for In Vivo Microscopy, Department of Radiology, Duke University Medical Center, Durham, North Carolina (United States); Das, Shiva [Department of Radiation Oncology, Duke University Medical Center, Durham, North Carolina (United States); Johnson, G. Allan; Badea, Cristian T. [Center for In Vivo Microscopy, Department of Radiology, Duke University Medical Center, Durham, North Carolina (United States); Kirsch, David G., E-mail: david.kirsch@duke.edu [Department of Radiation Oncology, Duke University Medical Center, Durham, North Carolina (United States); Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, North Carolina (United States)

    2014-03-01

    Purpose: To develop a mouse model of cardiac injury after partial heart irradiation (PHI) and to test whether dual energy (DE)-microCT and 4-dimensional (4D)-microCT can be used to assess cardiac injury after PHI to complement myocardial perfusion imaging using micro-single photon emission computed tomography (SPECT). Methods and Materials: To study cardiac injury from tangent field irradiation in mice, we used a small-field biological irradiator to deliver a single dose of 12 Gy x-rays to approximately one-third of the left ventricle (LV) of Tie2Cre; p53{sup FL/+} and Tie2Cre; p53{sup FL/−} mice, where 1 or both alleles of p53 are deleted in endothelial cells. Four and 8 weeks after irradiation, mice were injected with gold and iodinated nanoparticle-based contrast agents, and imaged with DE-microCT and 4D-microCT to evaluate myocardial vascular permeability and cardiac function, respectively. Additionally, the same mice were imaged with microSPECT to assess myocardial perfusion. Results: After PHI with tangent fields, DE-microCT scans showed a time-dependent increase in accumulation of gold nanoparticles (AuNp) in the myocardium of Tie2Cre; p53{sup FL/−} mice. In Tie2Cre; p53{sup FL/−} mice, extravasation of AuNp was observed within the irradiated LV, whereas in the myocardium of Tie2Cre; p53{sup FL/+} mice, AuNp were restricted to blood vessels. In addition, data from DE-microCT and microSPECT showed a linear correlation (R{sup 2} = 0.97) between the fraction of the LV that accumulated AuNp and the fraction of LV with a perfusion defect. Furthermore, 4D-microCT scans demonstrated that PHI caused a markedly decreased ejection fraction, and higher end-diastolic and end-systolic volumes, to develop in Tie2Cre; p53{sup FL/−} mice, which were associated with compensatory cardiac hypertrophy of the heart that was not irradiated. Conclusions: Our results show that DE-microCT and 4D-microCT with nanoparticle-based contrast agents are novel imaging approaches

  3. Assessing Cardiac Injury in Mice With Dual Energy-MicroCT, 4D-MicroCT, and MicroSPECT Imaging After Partial Heart Irradiation

    International Nuclear Information System (INIS)

    Purpose: To develop a mouse model of cardiac injury after partial heart irradiation (PHI) and to test whether dual energy (DE)-microCT and 4-dimensional (4D)-microCT can be used to assess cardiac injury after PHI to complement myocardial perfusion imaging using micro-single photon emission computed tomography (SPECT). Methods and Materials: To study cardiac injury from tangent field irradiation in mice, we used a small-field biological irradiator to deliver a single dose of 12 Gy x-rays to approximately one-third of the left ventricle (LV) of Tie2Cre; p53FL/+ and Tie2Cre; p53FL/− mice, where 1 or both alleles of p53 are deleted in endothelial cells. Four and 8 weeks after irradiation, mice were injected with gold and iodinated nanoparticle-based contrast agents, and imaged with DE-microCT and 4D-microCT to evaluate myocardial vascular permeability and cardiac function, respectively. Additionally, the same mice were imaged with microSPECT to assess myocardial perfusion. Results: After PHI with tangent fields, DE-microCT scans showed a time-dependent increase in accumulation of gold nanoparticles (AuNp) in the myocardium of Tie2Cre; p53FL/− mice. In Tie2Cre; p53FL/− mice, extravasation of AuNp was observed within the irradiated LV, whereas in the myocardium of Tie2Cre; p53FL/+ mice, AuNp were restricted to blood vessels. In addition, data from DE-microCT and microSPECT showed a linear correlation (R2 = 0.97) between the fraction of the LV that accumulated AuNp and the fraction of LV with a perfusion defect. Furthermore, 4D-microCT scans demonstrated that PHI caused a markedly decreased ejection fraction, and higher end-diastolic and end-systolic volumes, to develop in Tie2Cre; p53FL/− mice, which were associated with compensatory cardiac hypertrophy of the heart that was not irradiated. Conclusions: Our results show that DE-microCT and 4D-microCT with nanoparticle-based contrast agents are novel imaging approaches complementary to microSPECT for

  4. Temporal resolution and motion artifacts in single-source and dual-source cardiac CT

    Energy Technology Data Exchange (ETDEWEB)

    Schoendube, Harald; Allmendinger, Thomas; Stierstorfer, Karl; Bruder, Herbert; Flohr, Thomas [Siemens AG, Healthcare Sector, Computed Tomography, 91301 Forchheim (Germany)

    2013-03-15

    Purpose: The temporal resolution of a given image in cardiac computed tomography (CT) has so far mostly been determined from the amount of CT data employed for the reconstruction of that image. The purpose of this paper is to examine the applicability of such measures to the newly introduced modality of dual-source CT as well as to methods aiming to provide improved temporal resolution by means of an advanced image reconstruction algorithm. Methods: To provide a solid base for the examinations described in this paper, an extensive review of temporal resolution in conventional single-source CT is given first. Two different measures for assessing temporal resolution with respect to the amount of data involved are introduced, namely, either taking the full width at half maximum of the respective data weighting function (FWHM-TR) or the total width of the weighting function (total TR) as a base of the assessment. Image reconstruction using both a direct fan-beam filtered backprojection with Parker weighting as well as using a parallel-beam rebinning step are considered. The theory of assessing temporal resolution by means of the data involved is then extended to dual-source CT. Finally, three different advanced iterative reconstruction methods that all use the same input data are compared with respect to the resulting motion artifact level. For brevity and simplicity, the examinations are limited to two-dimensional data acquisition and reconstruction. However, all results and conclusions presented in this paper are also directly applicable to both circular and helical cone-beam CT. Results: While the concept of total TR can directly be applied to dual-source CT, the definition of the FWHM of a weighting function needs to be slightly extended to be applicable to this modality. The three different advanced iterative reconstruction methods examined in this paper result in significantly different images with respect to their motion artifact level, despite exactly the same

  5. High-concentration contrast media in neurological multidetector-row CT applications: implications for improved patient management in neurology and neurosurgery

    Energy Technology Data Exchange (ETDEWEB)

    Schramm, Peter [University of Heidelberg Medical Center, Department of Neuroradiology, Heidelberg (Germany)

    2007-07-15

    Dynamic CT scanning after intravenous injection of iodine contrast medium (CM) was proposed in the very early days of CT. The goal was to characterize tissue by extracting information from the temporal course of enhancement. In the early 1980s, modeling algorithms were already described in the literature for the quantitative calculation of cerebral blood flow (CBF). However, cerebral applications suffered from the insufficient temporal resolution available at that time and the central nervous system was already seen primarily as an MRI domain. The renaissance of dynamic CT in neurological applications came in the middle of the 1990s with the introduction of thrombolytic therapy in acute stroke. With CT being the primary imaging modality, getting additional hemodynamic information from the same device without having to move the patient appeared attractive. Multimodal CT protocols allow a comprehensive diagnosis of the emergency stroke patient in less than 15 minutes by combining nonenhanced CT (NECT), perfusion CT (PCT) and CT angiography (CTA). Dynamic PCT can also render important information in patients with intraaxial brain tumors, allowing differentiation not only between lymphoma and glioma but also between low-grade and high-grade glioma by quantifying local cerebral blood volume (CBV) and permeability of the blood-brain barrier (BBB). Hoever, even if a shorter imaging time permits a reduction in volume of CM, adequate total iodine levels must be preserved for dynamic CT applications. Increased concentrations of iodine are therefore helpful to obtain adequate total iodine levels for imaging. (orig.)

  6. A dual tracer (68)Ga-DOTANOC PET/CT and (18)F-FDG PET/CT pilot study for detection of cardiac sarcoidosis

    DEFF Research Database (Denmark)

    Gormsen, Lars C; Haraldsen, Ate; Kramer, Stine;

    2016-01-01

    BACKGROUND: Cardiac sarcoidosis (CS) is a potentially fatal condition lacking a single test with acceptable diagnostic accuracy. (18)F-FDG PET/CT has emerged as a promising imaging modality, but is challenged by physiological myocardial glucose uptake. An alternative tracer, (68)Ga-DOTANOC, binds...

  7. Children's (Pediatric) CT (Computed Tomography)

    Medline Plus

    Full Text Available ... top of page What are the benefits vs. risks? Benefits Using a multidetector CT unit to examine ... CT scans should have no immediate side effects. Risks The risk of serious allergic reaction to contrast ...

  8. Myocardial Extracellular Volume Fraction with Dual-Energy Equilibrium Contrast-enhanced Cardiac CT in Nonischemic Cardiomyopathy: A Prospective Comparison with Cardiac MR Imaging.

    Science.gov (United States)

    Lee, Hye-Jeong; Im, Dong Jin; Youn, Jong-Chan; Chang, Suyon; Suh, Young Joo; Hong, Yoo Jin; Kim, Young Jin; Hur, Jin; Choi, Byoung Wook

    2016-07-01

    Purpose To evaluate the feasibility of equilibrium contrast material-enhanced dual-energy cardiac computed tomography (CT) to determine extracellular volume fraction (ECV) in nonischemic cardiomyopathy (CMP) compared with magnetic resonance (MR) imaging. Materials and Methods This study was approved by the institutional review board; informed consent was obtained. Seven healthy subjects and 23 patients (six with hypertrophic CMP, nine with dilated CMP, four with amyloidosis, and four with sarcoidosis) (mean age ± standard deviation, 57.33 years ± 14.82; 19 male participants [63.3%]) were prospectively enrolled. Twelve minutes after contrast material injection (1.8 mL/kg at 3 mL/sec), dual-energy cardiac CT was performed. ECV was measured by two observers independently. Hematocrit levels were compared between healthy subjects and patients with the Mann-Whitney U test. In per-subject analysis, interobserver agreement for CT was assessed with the intraclass correlation coefficient (ICC), and intertest agreement between MR imaging and CT was assessed with Bland-Altman analysis. In per-segment analysis, Student t tests in the linear mixed model were used to compare ECV on CT images between healthy subjects and patients. Results Hematocrit level was 43.44% ± 1.80 for healthy subjects and 41.23% ± 5.61 for patients with MR imaging (P = .16) and 43.50% ± 1.92 for healthy subjects and 41.35% ± 5.92 for patients with CT (P = .15). For observer 1 in per-subject analysis, ECV was 34.18% ± 8.98 for MR imaging and 34.48% ± 8.97 for CT. For observer 2, myocardial ECV was 34.42% ± 9.03 for MR imaging and 33.98% ± 9.05 for CT. Interobserver agreement for ECV at CT was excellent (ICC = 0.987). Bland-Altman analysis between MR imaging and CT showed a small bias (-0.06%), with 95% limits of agreement of -1.19 and 1.79. Compared with healthy subjects, patients with hypertrophic CMP, dilated CMP, amyloidosis, and sarcoidosis had significantly higher myocardial ECV at dual

  9. Improving Low-dose Cardiac CT Images based on 3D Sparse Representation

    Science.gov (United States)

    Shi, Luyao; Hu, Yining; Chen, Yang; Yin, Xindao; Shu, Huazhong; Luo, Limin; Coatrieux, Jean-Louis

    2016-03-01

    Cardiac computed tomography (CCT) is a reliable and accurate tool for diagnosis of coronary artery diseases and is also frequently used in surgery guidance. Low-dose scans should be considered in order to alleviate the harm to patients caused by X-ray radiation. However, low dose CT (LDCT) images tend to be degraded by quantum noise and streak artifacts. In order to improve the cardiac LDCT image quality, a 3D sparse representation-based processing (3D SR) is proposed by exploiting the sparsity and regularity of 3D anatomical features in CCT. The proposed method was evaluated by a clinical study of 14 patients. The performance of the proposed method was compared to the 2D spares representation-based processing (2D SR) and the state-of-the-art noise reduction algorithm BM4D. The visual assessment, quantitative assessment and qualitative assessment results show that the proposed approach can lead to effective noise/artifact suppression and detail preservation. Compared to the other two tested methods, 3D SR method can obtain results with image quality most close to the reference standard dose CT (SDCT) images.

  10. Performance of automated software in the assessment of segmental left ventricular function in cardiac CT: Comparison with cardiac magnetic resonance

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Rui [Medical University of South Carolina, Department of Radiology and Radiological Science, Charleston, SC (United States); Capital Medical University, Department of Radiology, Beijing Anzhen Hospital, Beijing (China); Meinel, Felix G. [Medical University of South Carolina, Department of Radiology and Radiological Science, Charleston, SC (United States); Ludwig-Maximilians-University Hospital, Institute for Clinical Radiology, Munich (Germany); Schoepf, U.J. [Medical University of South Carolina, Department of Radiology and Radiological Science, Charleston, SC (United States); Medical University of South Carolina, Division of Cardiology, Department of Medicine, Charleston, SC (United States); Canstein, Christian [Siemens Medical Solutions USA, Malvern, PA (United States); Spearman, James V. [Medical University of South Carolina, Department of Radiology and Radiological Science, Charleston, SC (United States); De Cecco, Carlo N. [Medical University of South Carolina, Department of Radiology and Radiological Science, Charleston, SC (United States); University of Rome ' ' Sapienza' ' , Departments of Radiological Sciences, Oncology and Pathology, Latina (Italy)

    2015-12-15

    To evaluate the accuracy, reliability and time saving potential of a novel cardiac CT (CCT)-based, automated software for the assessment of segmental left ventricular function compared to visual and manual quantitative assessment of CCT and cardiac magnetic resonance (CMR). Forty-seven patients with suspected or known coronary artery disease (CAD) were enrolled in the study. Wall thickening was calculated. Segmental LV wall motion was automatically calculated and shown as a colour-coded polar map. Processing time for each method was recorded. Mean wall thickness in both systolic and diastolic phases on polar map, CCT, and CMR was 9.2 ± 0.1 mm and 14.9 ± 0.2 mm, 8.9 ± 0.1 mm and 14.5 ± 0.1 mm, 8.3 ± 0.1 mm and 13.6 ± 0.1 mm, respectively. Mean wall thickening was 68.4 ± 1.5 %, 64.8 ± 1.4 % and 67.1 ± 1.4 %, respectively. Agreement for the assessment of LV wall motion between CCT, CMR and polar maps was good. Bland-Altman plots and ICC indicated good agreement between CCT, CMR and automated polar maps of the diastolic and systolic segmental wall thickness and thickening. The processing time using polar map was significantly decreased compared with CCT and CMR. Automated evaluation of segmental LV function with polar maps provides similar measurements to manual CCT and CMR evaluation, albeit with substantially reduced analysis time. (orig.)

  11. Multi-slice and dual-source CT in cardiac imaging. Principles - protocols - indications - outlook. 2. ed.

    Energy Technology Data Exchange (ETDEWEB)

    Ohnesorge, B.M. [Siemens Medical Solutions Group China, Beijing (China); Flohr, T.G. [Siemens Medical Solutions, Forchheim (Germany). Div. CT Physics and Applications Development; Becker, C.R.; Reiser, M.F. [Muenchen Univ. Klinikum Grosshadern (Germany). Dept. of Clinical Radiology; Knez, A [Muenchen Univ. Klinikum Grosshadern (Germany). Section Head Imaging

    2007-07-01

    Cardiac diseases, and in particular coronary artery disease, are the leading cause of death and morbidity in industrialized countries. The development of non-invasive imaging techniques for the heart and the coronary arteries has been considered a key element in improving patient care. A breakthrough in cardiac imaging using CT occurred in 1998, with the introduction of multi-slice computed tomography (CT). Since then, amazing advances in performance have taken place with scanners that acquire up to 64 slices per rotation. This book discusses the state-of-the-art developments in multi-slice CT for cardiac imaging as well as those that can be anticipated in the future. It serves as a comprehensive work that covers all aspects of this technology, from the technical fundamentals and image evaluation all the way to clinical indications and protocol recommendations. This fully reworked second edition draws on the most recent clinical experience obtained with 16- and 64-slice CT scanners by world-leading experts from Europe and the United States. It also includes 'hands-on' experience in the form of 10 representative clinical case studies, which are included on the accompanying CD. As a further highlight, the latest results of the very recently introduced dual-source CT, which may soon represent the CT technology of choice for cardiac applications, are presented. This book will not only convince the reader that multi-slice cardiac CT has arrived in clinical practice, it will also make a significant contribution to the education of radiologists, cardiologists, technologists, and physicists-whether newcomers, experienced users, or researchers. (orig.)

  12. Surface based cardiac and respiratory motion extraction for pulmonary structures from multi-phase CT

    Science.gov (United States)

    von Berg, Jens; Barschdorf, Hans; Blaffert, Thomas; Kabus, Sven; Lorenz, Cristian

    2007-03-01

    During medical imaging and therapeutic interventions, pulmonary structures are in general subject to cardiac and respiratory motion. This motion leads potentially to artefacts and blurring in the resulting image material and to uncertainties during interventions. This paper presents a new automatic approach for surface based motion tracking of pulmonary structures and reports on the results for cardiac and respiratory induced motion. The method applies an active shape approach to ad-hoc generated surface representations of the pulmonary structures for phase to phase surface tracking. Input of the method are multi-phase CT data, either cardiac or respiratory gated. The iso-surface representing the transition between air or lung parenchyma to soft tissue, is triangulated for a selected phase p 0. An active shape procedure is initialised in the image of phase p I using the generated surface in p 0. The used internal energy term penalizes shape deformation as compared to p 0. The process is iterated for all phases p i to p i+1 of the complete cycle. Since the mesh topology is the same for all phases, the vertices of the triangular mesh can be treated as pseudo-landmarks defining tissue trajectories. A dense motion field is interpolated. The motion field was especially designed to estimate the error margins for radiotherapy. In the case of respiratory motion extraction, a validation on ten biphasic thorax CT images (2.5mm slice distance) was performed with expert landmarks placed at vessel bifurcations. The mean error on landmark position was below 2.6mm. We further applied the method to ECG gated images and estimated the influence of the heart beat on lung tissue displacement.

  13. Estudio del oído con TC Multidetector de 64 canales 64 - Detector CT findings in the study of the ear

    Directory of Open Access Journals (Sweden)

    María Lourdes Mallo

    2010-12-01

    Full Text Available El oído es una estructura anatómica compleja. Su estudio y comprensión resultan un reto diario para el radiólogo, siendo la tomografía computada una herramienta esencial para su estudio. La tomografía computada convencional con cortes finos en planos axiales y coronales permite una buena visualización de las diferentes estructuras. Sin embargo, se necesitan tiempos prolongados para su realización y posicionamientos incómodos o intolerables para muchos pacientes. Además la visualización de algunas de sus estructuras es limitada. La tomografía axial computada multidetector de 64 canales a nuestro medio permite optimizar el estudio de la compleja y pequeña anatomía del oído. La realización de adquisiciones volumétricas con cortes de 0,5 mm, con reconstrucciones multiplanares en los tres planos básicos, en planos curvos y reconstrucciones tridimensionales, hacen posible la visualización detallada de las estructuras en escasos segundos y en condiciones cómodas para el paciente. Nuestro propósito en este artículo es demostrar la utilidad de las reconstrucciones, particularmente en planos oblicuos, para identificar y analizar los diferentes reparos anatómicos del oído y alcanzar la visualización óptima de la anatomía relevante del hueso temporal.The ear is a complex anatomic structure. Its study and understanding represent a constant challenge for the radiologist. As a consequence the computed tomography becomes an essential tool for its examination. Conventional tomographic examination with both axial and coronal reconstruction of the image allows a satisfactory visualization of the different structures. However, the study requires long periods of time for its acquisition and uncomfortable or intolerable positions for the patients. Moreover, the characterization of some structures of the ear becomes limited. Sixty-four slice multidetector computed tomography allows the optimal study of the small and complex ear anatomy

  14. Novel phase-based noise reduction strategy for quantification of left ventricular function and mass assessment by cardiac CT: Comparison with cardiac magnetic resonance

    Energy Technology Data Exchange (ETDEWEB)

    Wai, Bryan, E-mail: bwai@partners.org [Cardiac MR PET CT Program, Division of Cardiology and Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts (United States); Thai, Wai-ee [Cardiac MR PET CT Program, Division of Cardiology and Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts (United States); Brown, Heather [Qi Imaging, Redwood City, California (United States); Truong, Quynh A. [Cardiac MR PET CT Program, Division of Cardiology and Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts (United States)

    2013-08-15

    Background: Tube current modulation in retrospective ECG gated cardiac computed tomography (CT) results in increased image noise and may reduce the accuracy of left ventricular (LV) ejection fraction (EF) and mass assessment. Objective: To examine the effects of a novel CT phase-based noise reduction (NR) algorithm on LV EF and mass quantification as compared to cardiac magnetic resonance (CMR). Methods: In 40 subjects, we compared the LV EF and mass between CT and CMR. In a subset of 24 subjects with tube current modulated CT, the effect of phase-based noise reduction strategies on contrast-to-noise ratio (CNR) and the assessment of LV EF and mass was compared to CMR. Results: There was excellent correlation between CT and CMR for EF (r = 0.94) and mass (r = 0.97). As compared to CMR, the limits of agreement improved with increasing strength of NR strategy. There was a systematic underestimation of LV mass by CT compared to CMR with no NR (−10.3 ± 10.1 g) and low NR (−10.3 ± 12.5 g), but was attenuated with high NR (−0.5 ± 8.3 g). Studies without NR had lower CNR compared to low and high NR at both the ES phase and ED phase (all p < 0.01). Conclusions: A high NR strategy on tube current modulated functional cardiac CT improves correlation of EF compared to CMR and reduces variability of EF and mass evaluation by increasing the CNR. In an effort to reduce radiation dose with tube current modulation, this strategy provides better image quality when LV function and mass quantification is needed.

  15. Novel phase-based noise reduction strategy for quantification of left ventricular function and mass assessment by cardiac CT: Comparison with cardiac magnetic resonance

    International Nuclear Information System (INIS)

    Background: Tube current modulation in retrospective ECG gated cardiac computed tomography (CT) results in increased image noise and may reduce the accuracy of left ventricular (LV) ejection fraction (EF) and mass assessment. Objective: To examine the effects of a novel CT phase-based noise reduction (NR) algorithm on LV EF and mass quantification as compared to cardiac magnetic resonance (CMR). Methods: In 40 subjects, we compared the LV EF and mass between CT and CMR. In a subset of 24 subjects with tube current modulated CT, the effect of phase-based noise reduction strategies on contrast-to-noise ratio (CNR) and the assessment of LV EF and mass was compared to CMR. Results: There was excellent correlation between CT and CMR for EF (r = 0.94) and mass (r = 0.97). As compared to CMR, the limits of agreement improved with increasing strength of NR strategy. There was a systematic underestimation of LV mass by CT compared to CMR with no NR (−10.3 ± 10.1 g) and low NR (−10.3 ± 12.5 g), but was attenuated with high NR (−0.5 ± 8.3 g). Studies without NR had lower CNR compared to low and high NR at both the ES phase and ED phase (all p < 0.01). Conclusions: A high NR strategy on tube current modulated functional cardiac CT improves correlation of EF compared to CMR and reduces variability of EF and mass evaluation by increasing the CNR. In an effort to reduce radiation dose with tube current modulation, this strategy provides better image quality when LV function and mass quantification is needed

  16. Automatic cable artifact removal for cardiac C-arm CT imaging

    Science.gov (United States)

    Haase, C.; Schäfer, D.; Kim, M.; Chen, S. J.; Carroll, J.; Eshuis, P.; Dössel, O.; Grass, M.

    2014-03-01

    Cardiac C-arm computed tomography (CT) imaging using interventional C-arm systems can be applied in various areas of interventional cardiology ranging from structural heart disease and electrophysiology interventions to valve procedures in hybrid operating rooms. In contrast to conventional CT systems, the reconstruction field of view (FOV) of C-arm systems is limited to a region of interest in cone-beam (along the patient axis) and fan-beam (in the transaxial plane) direction. Hence, highly X-ray opaque objects (e.g. cables from the interventional setup) outside the reconstruction field of view, yield streak artifacts in the reconstruction volume. To decrease the impact of these streaks a cable tracking approach on the 2D projection sequences with subsequent interpolation is applied. The proposed approach uses the fact that the projected position of objects outside the reconstruction volume depends strongly on the projection perspective. By tracking candidate points over multiple projections only objects outside the reconstruction volume are segmented in the projections. The method is quantitatively evaluated based on 30 simulated CT data sets. The 3D root mean square deviation to a reference image could be reduced for all cases by an average of 50 % (min 16 %, max 76 %). Image quality improvement is shown for clinical whole heart data sets acquired on an interventional C-arm system.

  17. Renal safety in pediatric imaging: randomized, double-blind phase IV clinical trial of iobitridol 300 versus iodixanol 270 in multidetector CT

    International Nuclear Information System (INIS)

    It is debated whether iso-osmolar and low-osmolar contrast media are associated with different incidences of contrast medium-induced nephropathy (CIN) in patients with renal insufficiency. To compare the incidence of CIN in children undergoing contrast-enhanced multidetector computer tomography (MDCT) with intravenous injection of low-osmolar (iobitridol, Xenetix registered 300) or an iso-osmolar (iodixanol, Visipaque registered 270) iodinated contrast medium. One hundred forty-six children with normal renal function were included in this multicenter trial and underwent contrast-enhanced MDCT. The primary endpoint was the relative change in creatinine clearance from 48 h pre- to 72 h postcontrast medium administration using a noninferiority analysis in the intent-to-treat (ITT, n = 128) and per protocol (n = 68) populations. Secondary endpoints were incidence of CIN, global image quality, diagnostic efficacy and clinical safety. In the ITT population, the noninferiority of iobitridol over iodixanol was demonstrated. CIN incidence was 4.8% (three cases) with iobitridol and 10.6% (seven cases) with iodixanol (not significant). No statistically significant differences were observed for the secondary endpoints. Comparable satisfactory safety profiles were confirmed for both contrast media, with no significant difference in the incidence of CIN in children with normal renal function. (orig.)

  18. Dose reduction for cardiac CT using a registration-based approach

    International Nuclear Information System (INIS)

    Two reasons for the recent rise in radiation exposure from CT are increases in its clinical applicability and the desire to maintain high SNR while acquiring smaller voxels. To address this emerging dose problem, several strategies for reducing patient exposure have already been proposed. One method employed in cardiac imaging is ECG-driven modulation of the tube current between 100% at one time point in the cardiac cycle and a reduced fraction at the remaining phases. In this paper, we describe how images obtained during such acquisition can be used to reconstruct 4D data of consistent high quality throughout the cardiac cycle. In our approach, we assume that the mid-diastole (MD) phase is imaged with full dose. The MD image is then independently registered to lower dose images (lower SNR) at other frames, resulting in a set of transformations. Finally, the transformations are used to warp the MD frame through the cardiac cycle to generate the full 4D image. In addition, the transformations may be interpolated to increase the temporal sampling or to generate images at arbitrary time points. Our approach was validated using various data obtained with simulated and scanner-implemented dose modulation. We determined that as little as 10% of the total dose was required to reproduce full quality images with a 1 mm spatial error and an error in intensity values on the order of the image noise. Thus, our technique offers considerable dose reductions compared to standard imaging protocols, with minimal effects on the quality of the final data

  19. Split-bolus single-phase cardiac multidetector computed tomography for reliable detection of left atrial thrombus. Comparison to transesophageal echocardiography

    Energy Technology Data Exchange (ETDEWEB)

    Staab, W.; Zwaka, P.A.; Sohns, J.M.; Schwarz, A.; Lotz, J. [University Medical Center Goettingen Univ. (Germany). Inst. for Diagnostic and Interventional Radiology; Sohns, C.; Vollmann, D.; Zabel, M.; Hasenfuss, G. [Goettingen Univ. (Germany). Dept. of Cardiology and Pneumology; Schneider, S. [Goettingen Univ. (Germany). Dept. of Medical Statistics

    2014-11-15

    Evaluation of a new cardiac MDCT protocol using a split-bolus contrast injection protocol and single MDCT scan for reliable diagnosis of LA/LAA thrombi in comparison to TEE, optimizing radiation exposure and use of contrast agent. A total of 182 consecutive patients with drug refractory AF scheduled for PVI (62.6% male, mean age: 64.1 ± 10.2 years) underwent routine diagnostic work including TEE and cardiac MDCT for the evaluation of LA/LAA anatomy and thrombus formation between November 2010 and March 2012. Contrast media injection was split into a pre-bolus of 30 ml and main bolus of 70 ml iodinated contrast agent separated by a short time delay. In this study, split-bolus cardiac MDCT identified 14 of 182 patients with filling defects of the LA/LAA. In all of these 14 patients, abnormalities were found in TEE. All 5 of the 14 patients with thrombus formation in cardiac MDCT were confirmed by TEE. MDCT was 100% accurate for thrombus, with strong but not perfect overall results for SEC equivalent on MDCT.

  20. A registration based approach for 4D cardiac micro-CT using combined prospective and retrospective gating

    Science.gov (United States)

    Badea, Cristian T.; Schreibmann, Eduard; Fox, Tim

    2008-01-01

    Recent advances in murine cardiac studies with three-dimensional cone beam micro-computed tomography (CT) have used either prospective or retrospective gating technique. While prospective gating ensures the best image quality and the highest resolution, it involves longer sampling times and higher radiation dose. Sampling is faster and the radiation dose can be reduced with retrospective gating but the image quality is affected by the limited number of projections with an irregular angular distribution which complicate the reconstruction process, causing significant streaking artifacts. This work involves both prospective and retrospective gating in sampling. Deformable registration is used between a high quality image set acquired with prospective gating with the multiple data sets during the cardiac cycle obtained using retrospective gating. Tests were conducted on a four-dimensional (4D) cardiac mouse phantom and after optimization, the method was applied to in vivo cardiac micro-CT data. Results indicate that, by using our method, the sampling time can be reduced by a factor of 2.5 and the radiation dose can be reduced 35% compared to the prospective sampling while the image quality can be maintained. In conclusion, we proposed a novel solution to 4D cine cardiac micro-CT based on a combined prospective with retrospective gating in sampling and deformable registration post reconstruction that mixed the advantages of both strategies. PMID:18491508

  1. Bicuspid aortic valves: Diagnostic accuracy of standard axial 64-slice chest CT compared to aortic valve image plane ECG-gated cardiac CT

    International Nuclear Information System (INIS)

    Objectives: To assess the diagnostic accuracy of standard axial 64-slice chest CT compared to aortic valve image plane ECG-gated cardiac CT for bicuspid aortic valves. Materials and methods: The standard axial chest CT scans of 20 patients with known bicuspid aortic valves were blindly, randomly analyzed for (i) the appearance of the valve cusps, (ii) the largest aortic sinus area, (iii) the longest aortic cusp length, (iv) the thickest aortic valve cusp and (v) valve calcification. A second blinded reader independently analyzed the appearance of the valve cusps. Forty-two age- and sex-matched patients with known tricuspid aortic valves were used as controls. Retrospectively ECG-gated cardiac CT multiphase reconstructions of the aortic valve were used as the gold-standard. Results: Fourteen (21%) scans were scored as unevaluable (7 bicuspid, 7 tricuspid). Of the remainder, there were 13 evaluable bicuspid valves, ten of which showed an aortic valve line sign, while the remaining three showed a normal Mercedes-Benz appearance owing to fused valve cusps. The 35 evaluable tricuspid aortic valves all showed a normal Mercedes-Benz appearance (P = 0.001). Kappa analysis = 0.62 indicating good interobserver agreement for the aortic valve cusp appearance. Aortic sinus areas, aortic cusp lengths and aortic cusp thicknesses of ≥3.8 cm2, 3.2 cm and 1.6 mm respectively on standard axial chest CT best distinguished bicuspid from tricuspid aortic valves (P < 0.0001 for all). Of evaluable scans, the sensitivity, specificity, positive and negative predictive values of standard axial chest CT in diagnosing bicuspid aortic valves was 77% (CI 0.54–1.0), 100%, 100% and 70% respectively. Conclusion: The aortic valve is evaluable in approximately 80% of standard chest 64-slice CT scans. Bicuspid aortic valves may be diagnosed on evaluable scans with good diagnostic accuracy. An aortic valve line sign, enlarged aortic sinuses and elongated, thickened valve cusps are specific CT

  2. Multidetector computed tomography pulmonary angiography in childhood acute pulmonary embolism

    Energy Technology Data Exchange (ETDEWEB)

    Tang, Chun Xiang; Zhang, Long Jiang; Lu, Guang Ming [Medical School of Nanjing University, Department of Medical Imaging, Jinling Hospital, Nanjing, Jiangsu (China); Schoepf, U.J. [Medical School of Nanjing University, Department of Medical Imaging, Jinling Hospital, Nanjing, Jiangsu (China); Medical University of South Carolina, Department of Radiology and Radiological Science, Charleston, SC (United States); Medical University of South Carolina, Department of Pediatrics, Charleston, SC (United States); Chowdhury, Shahryar M. [Medical University of South Carolina, Department of Pediatrics, Charleston, SC (United States); Fox, Mary A. [Medical University of South Carolina, Department of Radiology and Radiological Science, Charleston, SC (United States)

    2015-09-15

    Pulmonary embolism is a life-threatening condition affecting people of all ages. Multidetector row CT pulmonary angiography has improved the imaging of pulmonary embolism in both adults and children and is now regarded as the routine modality for detection of pulmonary embolism. Advanced CT pulmonary angiography techniques developed in recent years, such as dual-energy CT, have been applied as a one-stop modality for pulmonary embolism diagnosis in children, as they can simultaneously provide anatomical and functional information. We discuss CT pulmonary angiography techniques, common and uncommon findings of pulmonary embolism in both conventional and dual-energy CT pulmonary angiography, and radiation dose considerations. (orig.)

  3. Low radiation dose imaging of myocardial perfusion and coronary angiography with a hybrid PET/CT scanner

    OpenAIRE

    Kajander, S; Ukkonen, H; Sipilä, H.; Teräs, M.; Knuuti, J

    2009-01-01

    Objectives: To test the image quality and feasibility of a sequential low radiation dose protocol for hybrid cardiac PET/CT angiography (CTA). Background: Multidetector computed tomography (MDCT) is a non-invasive method for coronary angiography. The negative predictive value of MDCT is high but perfusion imaging has a role in detecting functional significance of coronary lesions. This has encouraged combining these techniques. However, radiation dose is of concern. We report our first experi...

  4. Improvement of the temporal resolution of cardiac CT reconstruction algorithms using an optimized filtering step

    Energy Technology Data Exchange (ETDEWEB)

    Roux, S. [Universite Joseph Fourier, TIMC-IMAG, In3S, Faculte de Medecine, 38 - Grenoble (France)]|[CEA Grenoble, Lab. d' Electronique et de Technologie de l' Informatique (LETI), 38 (France); Desbat, L. [Universite Joseph Fourier, UMR CNRS 5525, 38 - Grenoble (France); Koenig, A.; Grangeat, P. [CEA Grenoble, Lab. d' Electronique et de Technologie de l' Informatique (LETI), 38 (France)

    2005-07-01

    In this paper we study a property of the filtering step of multi-cycle reconstruction algorithm used in the field of cardiac CT. We show that the common filtering step procedure is not optimal in the case of divergent geometry and decrease slightly the temporal resolution. We propose to use the filtering procedure related to the work of Noo at al ( F.Noo, M. Defrise, R. Clakdoyle, and H. Kudo. Image reconstruction from fan-beam projections on less than a short-scan. Phys. Med.Biol., 47:2525-2546, July 2002)and show that this alternative allows to reach the optimal temporal resolution with the same computational effort. (N.C.)

  5. Current role of cardiac and extra-cardiac pathologies in clinically indicated cardiac computed tomography with emphasis on status before pulmonary vein isolation

    Energy Technology Data Exchange (ETDEWEB)

    Sohns, J.M.; Lotz, J. [Goettingen University Medical Center (Germany). Inst. for Diagnostic and Interventional Radiology; German Center for Cardiovascular Research (DZHK), Goettingen (Germany); Menke, J.; Staab, W.; Fasshauer, M.; Kowallick, J.T.; Zwaka, P.A.; Schwarz, A. [Goettingen University Medical Center (Germany). Inst. for Diagnostic and Interventional Radiology; Spiro, J. [Koeln University Hospital (Germany). Radiology; Bergau, L.; Unterberg-Buchwald, C. [Goettingen University Medical Center (Germany). Cardiology and Pneumology

    2014-09-15

    Purpose: The aim of this study was to assess the incidence of cardiac and significant extra-cardiac findings in clinical computed tomography of the heart in patients with atrial fibrillation before pulmonary vein isolation (PVI). Materials and Methods: 224 patients (64 ± 10 years; male 63%) with atrial fibrillation were examined by cardiac 64-slice multidetector CT before PVI. Extra-cardiac findings were classified as 'significant' if they were recommended to additional diagnostics or therapy, and otherwise as 'non-significant'. Additionally, cardiac findings were documented in detail. Results: A total of 724 cardiac findings were identified in 203 patients (91% of patients). Additionally, a total of 619 extra-cardiac findings were identified in 179 patients (80% of patients). Among these extra-cardiac findings 196 (32%) were 'significant', and 423 (68%) were 'non-significant'. In 2 patients (1%) a previously unknown malignancy was detected (esophageal cancer and lung cancer, local stage, no metastasis). 203 additional imaging diagnostics followed to clarify the 'significant' findings (124 additional CT, costs 38,314.69 US dollars). Overall, there were 3.2 cardiac and 2.8 extra-cardiac findings per patient. Extra-cardiac findings appear significantly more frequently in patients over 60 years old, in smokers and in patients with a history of cardiac findings (p < 0.05). Conclusion: Cardiac CT scans before PVI should be screened for extracardiac incidental findings that could have important clinical implications for each patient. (orig.)

  6. Multi-detector thoracic CT findings in cerebro-costo-mandibular syndrome: rib gaps and failure of costo-vertebral separation

    Energy Technology Data Exchange (ETDEWEB)

    Watson, Tom Anthony; Arthurs, Owen John; Calder, Alistair Duncan [Great Ormond Street Hospital for Children NHS Foundation Trust, Department of Radiology, London (United Kingdom); Muthialu, Nagarajan [Great Ormond Street Hospital for Children NHS Foundation Trust, Department of Cardiothoracic surgery, London (United Kingdom)

    2014-02-15

    Cerebro-costo-mandibular syndrome (CCMS) describes a triad of mandibular hypoplasia, brain dysfunction and posterior rib defects (''rib gaps''). We present the CT imaging for a 2-year-old girl with CCMS that highlights the rib gap defects and shows absent transverse processes with abnormal fusion of the ribs directly to the vertebral bodies. We argue that this is likely to relate to abnormal lateral sclerotome development in embryology, with the failure of normal costo-vertebral junctions compounding impaired thoracic function. The case also highlights the use of CT for specific indications in skeletal dysplasia. (orig.)

  7. A framework of whole heart extracellular volume fraction estimation for low dose cardiac CT images

    Science.gov (United States)

    Chen, Xinjian; Summers, Ronald M.; Nacif, Marcelo Souto; Liu, Songtao; Bluemke, David A.; Yao, Jianhua

    2012-02-01

    Cardiac magnetic resonance imaging (CMRI) has been well validated and allows quantification of myocardial fibrosis in comparison to overall mass of the myocardium. Unfortunately, CMRI is relatively expensive and is contraindicated in patients with intracardiac devices. Cardiac CT (CCT) is widely available and has been validated for detection of scar and myocardial stress/rest perfusion. In this paper, we sought to evaluate the potential of low dose CCT for the measurement of myocardial whole heart extracellular volume (ECV) fraction. A novel framework was proposed for CCT whole heart ECV estimation, which consists of three main steps. First, a shape constrained graph cut (GC) method was proposed for myocardium and blood pool segmentation for post-contrast image. Second, the symmetric Demons deformable registrations method was applied to register pre-contrast to post-contrast images. Finally, the whole heart ECV value was computed. The proposed method was tested on 7 clinical low dose CCT datasets with pre-contrast and post-contrast images. The preliminary results demonstrated the feasibility and efficiency of the proposed method.

  8. Beam hardening and motion artifacts in cardiac CT: evaluation and iterative correction method

    Science.gov (United States)

    Shen, Zeyang; Lee, Okkyun; Taguchi, Katsuyuki

    2016-03-01

    For myocardial perfusion CT exams, beam hardening (BH) artifacts may degrade the accuracy of myocardial perfusion defect detection. Meanwhile, cardiac motion may make BH process inconsistent, which makes conventional BH correction (BHC) methods ineffective. The aims of this study were to assess the severity of BH artifacts and motion artifacts and propose a projection-based iterative BHC method which has a potential to handle the motion-induced inconsistency better than conventional methods. In this study, four sets of forward projection data were first acquired using both cylindrical phantoms and cardiac images as objects: (1) with monochromatic x-rays without motion; (2) with polychromatic x-rays without motion; (3) with monochromatic x-rays with motion; and (4) with polychromatic x-rays with motion. From each dataset, images were reconstructed using filtered back projection; for datasets 2 and 4, one of the following BHC methods was also performed: (A) no BHC; (B) BHC that concerns water only; and (C) BHC that takes both water and iodine into account, which is an iterative method we developed in this work. Biases of images were quantified by the mean absolute difference (MAD). The MAD of images with BH artifacts alone (dataset 2, without BHC) was comparable or larger than that of images with motion artifacts alone (dataset 3): In the study of cardiac image, BH artifacts account for over 80% of the total artifacts. The use of BHC was effective: with dataset 4, MAD values were 170 HU with no BHC, 54 HU with water BHC, and 42 HU with the proposed BHC. Qualitative improvements in image quality were also noticeable in reconstructed images.

  9. Anatomical-based partial volume correction for low-dose dedicated cardiac SPECT/CT

    Science.gov (United States)

    Liu, Hui; Chan, Chung; Grobshtein, Yariv; Ma, Tianyu; Liu, Yaqiang; Wang, Shi; Stacy, Mitchel R.; Sinusas, Albert J.; Liu, Chi

    2015-09-01

    Due to the limited spatial resolution, partial volume effect has been a major degrading factor on quantitative accuracy in emission tomography systems. This study aims to investigate the performance of several anatomical-based partial volume correction (PVC) methods for a dedicated cardiac SPECT/CT system (GE Discovery NM/CT 570c) with focused field-of-view over a clinically relevant range of high and low count levels for two different radiotracer distributions. These PVC methods include perturbation geometry transfer matrix (pGTM), pGTM followed by multi-target correction (MTC), pGTM with known concentration in blood pool, the former followed by MTC and our newly proposed methods, which perform the MTC method iteratively, where the mean values in all regions are estimated and updated by the MTC-corrected images each time in the iterative process. The NCAT phantom was simulated for cardiovascular imaging with 99mTc-tetrofosmin, a myocardial perfusion agent, and 99mTc-red blood cell (RBC), a pure intravascular imaging agent. Images were acquired at six different count levels to investigate the performance of PVC methods in both high and low count levels for low-dose applications. We performed two large animal in vivo cardiac imaging experiments following injection of 99mTc-RBC for evaluation of intramyocardial blood volume (IMBV). The simulation results showed our proposed iterative methods provide superior performance than other existing PVC methods in terms of image quality, quantitative accuracy, and reproducibility (standard deviation), particularly for low-count data. The iterative approaches are robust for both 99mTc-tetrofosmin perfusion imaging and 99mTc-RBC imaging of IMBV and blood pool activity even at low count levels. The animal study results indicated the effectiveness of PVC to correct the overestimation of IMBV due to blood pool contamination. In conclusion, the iterative PVC methods can achieve more accurate quantification, particularly for low

  10. Cardiac motion correction based on partial angle reconstructed images in x-ray CT

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Seungeon; Chang, Yongjin; Ra, Jong Beom, E-mail: jbra@kaist.ac.kr [Department of Electrical Engineering, KAIST, Daejeon 305-701 (Korea, Republic of)

    2015-05-15

    Purpose: Cardiac x-ray CT imaging is still challenging due to heart motion, which cannot be ignored even with the current rotation speed of the equipment. In response, many algorithms have been developed to compensate remaining motion artifacts by estimating the motion using projection data or reconstructed images. In these algorithms, accurate motion estimation is critical to the compensated image quality. In addition, since the scan range is directly related to the radiation dose, it is preferable to minimize the scan range in motion estimation. In this paper, the authors propose a novel motion estimation and compensation algorithm using a sinogram with a rotation angle of less than 360°. The algorithm estimates the motion of the whole heart area using two opposite 3D partial angle reconstructed (PAR) images and compensates the motion in the reconstruction process. Methods: A CT system scans the thoracic area including the heart over an angular range of 180° + α + β, where α and β denote the detector fan angle and an additional partial angle, respectively. The obtained cone-beam projection data are converted into cone-parallel geometry via row-wise fan-to-parallel rebinning. Two conjugate 3D PAR images, whose center projection angles are separated by 180°, are then reconstructed with an angular range of β, which is considerably smaller than a short scan range of 180° + α. Although these images include limited view angle artifacts that disturb accurate motion estimation, they have considerably better temporal resolution than a short scan image. Hence, after preprocessing these artifacts, the authors estimate a motion model during a half rotation for a whole field of view via nonrigid registration between the images. Finally, motion-compensated image reconstruction is performed at a target phase by incorporating the estimated motion model. The target phase is selected as that corresponding to a view angle that is orthogonal to the center view angles of

  11. Multiplanar reformat and volume rendering of a multidetector CT scan for path planning a fluoroscopic procedure on Gasserian ganglion block - a preliminary report

    Energy Technology Data Exchange (ETDEWEB)

    Horiguchi, Jun; Ishifuro, Minoru; Fukuda, Hiroshi; Akiyama, Yuji; Ito, Katsuhide

    2005-02-01

    In the treatment of trigeminal neuralgia, Gasserian block under fluoroscopical guidance may be difficult because of anatomic variability, and difficulty in identification of the foramen ovale. We introduce how to use three-dimensional CT in the preprocedural planning. We determine the skull-rotation angle in which the foramen ovale is best visualized, the relationship (distance, angle) between the virtual puncture point and anatomical landmarks, and the distance between the virtual puncture point and the foramen.

  12. Color-coded perfused blood volume imaging using multidetector CT: initial results of whole-brain perfusion analysis in acute cerebral ischemia

    Energy Technology Data Exchange (ETDEWEB)

    Kloska, Stephan P.; Fischer, Tobias; Fischbach, Roman; Heindel, Walter [University of Muenster, Department of Clinical Radiology, Muenster (Germany); Nabavi, Darius G.; Dittrich, Ralf; Ringelstein, E.B. [University of Muenster, Department of Neurology, Muenster (Germany); Ditt, Hendrik; Klotz, Ernst [Siemens AG, Medical Solutions, Forchheim (Germany)

    2007-09-15

    Computed tomography (CT) is still the primary imaging modality following acute stroke. To evaluate a prototype of software for the calculation of color-coded whole-brain perfused blood volume (PBV) images from CT angiography (CTA) and nonenhanced CT (NECT) scans, we studied 14 patients with suspected acute ischemia of the anterior cerebral circulation. PBV calculations were performed retrospectively. The detection rate of ischemic changes in the PBV images was compared with NECT. The volume of ischemic changes in PBV was correlated with the infarct volume on follow-up examination taking potential vessel recanalization into account. PBV demonstrated ischemic changes in 12/12 patients with proven infarction and was superior to NECT (8/12) in the detection of early ischemia. Moreover, PBV demonstrated the best correlation coefficient with the follow-up infarct volume (Pearson's R = 0.957; P = 0.003) for patients with proven recanalization of initially occluded cerebral arteries. In summary, PBV appears to be more accurate in the detection of early infarction compared to NECT and mainly visualizes the irreversibly damaged ischemic tissue. (orig.)

  13. The Incidence and Anatomy of Accessory Pudendal Arteries as Depicted on Multidetector-Row CT Angiography: Clinical Implications of Preoperative Evaluation for Laparoscopic and Robot-Assisted Radical Prostatectomy

    International Nuclear Information System (INIS)

    To help preserve accessory pudendal arteries (APAs) and to ensure optimal postoperative sexual function after a laparoscopic or robot-assisted radical prostatectomy, we have evaluated the incidence of APAs as detected on multidetector-row CT (MDCT) angiography and have provided a detailed anatomical description. The distribution of APAs was evaluated in 121 consecutive male patients between February 2006 and July 2007 who underwent 64- channel MDCT angiography of the lower extremities. We defined an APA as any artery located within the periprostatic region running parallel to the dorsal vascular complex. We also subclassified APAs into lateral and apical APAs. Two radiologists retrospectively evaluated the origin, course and number of APAs; the final APA subclassification based on MDCT angiography source data was determined by consensus. We identified 44 APAs in 36 of 121 patients (30%). Two distinct varieties of APAs were identified. Thirty-three APAs (75%) coursed near the anterolateral region of the prostatic apex, termed apical APAs. The remaining 11 APAs (25%) coursed along the lateral aspect of the prostate, termed lateral APAs. All APAs originated from the internal obturator artery and iliac artery or a branch of the iliac artery such as the inferior vesical artery. The majority of apical APAs arose from the internal obturator artery (84%). Seven patients (19%) had multiple APAs. APAs are more frequently detected by the use of MDCT angiography than as suggested by previous surgical studies. The identification of APAs on MDCT angiography may provide useful information for the surgical preservation of APAs during a laparoscopic or robot-assisted radical prostatectomy

  14. Low dose multi-detector CT of the chest (iLEAD Study): Visual ranking of different simulated mAs levels

    Energy Technology Data Exchange (ETDEWEB)

    Ley-Zaporozhan, Julia [Department of Diagnostic and Interventional Radiology, Ruprecht-Karls-University, Heidelberg (Germany); Department of Radiology (E010), German Cancer Research Center, Heidelberg (Germany)], E-mail: julia.leyzaporozhan@gmail.com; Ley, Sebastian [Department of Diagnostic and Interventional Radiology, Ruprecht-Karls-University, Heidelberg (Germany); Department of Radiology (E010), German Cancer Research Center, Heidelberg (Germany); Krummenauer, Frank [Clinical Epidemiology and Health Economy Unit, Carl Gustav Carus University Hospital, Dresden (Germany); Ohno, Yoshiharu [Department of Radiology, Kobe University Graduate School of Medicine, Kobe (Japan); Hatabu, Hiroto [Department of Radiology, Brigham and Women' s Hospital, Boston, MA (United States); Kauczor, Hans-Ulrich [Department of Diagnostic and Interventional Radiology, Ruprecht-Karls-University, Heidelberg (Germany)

    2010-02-15

    Purpose: Detailed evaluation of the lung parenchyma might be impaired by use of low dose CT as image noise increases and subsequently image quality decreases. The aim of our study was to determine the accuracy of visual perception of differences in image quality and noise at low dose chest CT. Materials and methods: Forty-four patients suffering from emphysema underwent CT (Aquilion-16, 120 kV, 150 mAs, 1 mm-collimation). Original raw data were used for simulation of 10 different mAs settings from 10 mAs to 100 mAs in 10 mAs increments. Three representative hard copy images (carina, 4 cm above, 5 cm below) were printed for evaluation of lung parenchyma (high-resolution kernel, lung window) and mediastinum (soft-kernel, soft tissue window). Ranking of expected low mAs level was performed for lung and soft tissue separately based on visual perception by three-blinded chest radiologist independently. Results were compared to the real simulated mAs. Results: The accuracy for correct ranking of the original 150 mAs scan was 89% for lung and 86% for soft tissue while it was 99% for the simulated 10 mAs for both windows. In comparison to the lowest mAs a significant error increase was found for the lung at 60-100 mAs (with error increase of 30-47%) for reader-I; 60-100 mAs for (33-64%) for reader-II and 70-100 mAs (38-57%) for reader-III. For the soft tissue: 60-150 mAs (with error increase of 28-63%) for reader-I; 50-100 mAs (35-56%) for reader-II and 50-90 mAs (35-40%) for reader-III. Conclusion: Simulated dose levels below 60 mAs (=42 mAs{sub eff}) were clearly differentiated from higher dose levels by all readers. Therefore, imaging doses could be lowered down to 60 mAs without a diagnostically relevant increase in noise impairing image quali0008.

  15. Image artefact propagation in motion estimation and reconstruction in interventional cardiac C-arm CT.

    Science.gov (United States)

    Müller, K; Maier, A K; Schwemmer, C; Lauritsch, G; De Buck, S; Wielandts, J-Y; Hornegger, J; Fahrig, R

    2014-06-21

    The acquisition of data for cardiac imaging using a C-arm computed tomography system requires several seconds and multiple heartbeats. Hence, incorporation of motion correction in the reconstruction step may improve the resulting image quality. Cardiac motion can be estimated by deformable three-dimensional (3D)/3D registration performed on initial 3D images of different heart phases. This motion information can be used for a motion-compensated reconstruction allowing the use of all acquired data for image reconstruction. However, the result of the registration procedure and hence the estimated deformations are influenced by the quality of the initial 3D images. In this paper, the sensitivity of the 3D/3D registration step to the image quality of the initial images is studied. Different reconstruction algorithms are evaluated for a recently proposed cardiac C-arm CT acquisition protocol. The initial 3D images are all based on retrospective electrocardiogram (ECG)-gated data. ECG-gating of data from a single C-arm rotation provides only a few projections per heart phase for image reconstruction. This view sparsity leads to prominent streak artefacts and a poor signal to noise ratio. Five different initial image reconstructions are evaluated: (1) cone beam filtered-backprojection (FDK), (2) cone beam filtered-backprojection and an additional bilateral filter (FFDK), (3) removal of the shadow of dense objects (catheter, pacing electrode, etc) before reconstruction with a cone beam filtered-backprojection (cathFDK), (4) removal of the shadow of dense objects before reconstruction with a cone beam filtered-backprojection and a bilateral filter (cathFFDK). The last method (5) is an iterative few-view reconstruction (FV), the prior image constrained compressed sensing combined with the improved total variation algorithm. All reconstructions are investigated with respect to the final motion-compensated reconstruction quality. The algorithms were tested on a mathematical

  16. CT of tracheal agenesis

    International Nuclear Information System (INIS)

    Tracheal agenesis is a rare and usually lethal anomaly. In the past, opaque contrast medium was injected via the esophagus to demonstrate the anatomy. To demonstrate the utility of helical and multidetector CT in delineating the aberrant anatomy in newborns with tracheal agenesis. Four newborns with tracheal agenesis were identified from three institutions. Imaging studies and medical records were reviewed. Each child was imaged with chest radiography. One child was imaged on a single-detector helical CT scanner and the other three on multidetector scanners. Helical and multidetector CT with 2D and 3D reconstructions clearly delineated the aberrant tracheobronchial and esophageal anatomy in each infant. Minimum intensity projection reformatted CT images were particularly helpful. One infant each had type I and type II tracheal agenesis. Two infants had type III tracheal agenesis. All four infants died. CT is a useful tool for delineating the aberrant anatomy of newborns with tracheal agenesis and thus helps in making rational clinical decisions. (orig.)

  17. CT of tracheal agenesis

    Energy Technology Data Exchange (ETDEWEB)

    Strouse, Peter J.; Hernandez, Ramiro J. [C.S. Mott Children' s Hospital, Department of Radiology, Ann Arbor, MI (United States); Newman, Beverley [Children' s Hospital of Pittsburgh, PA (United States). Department of Pediatric Radiology; Afshani, Ehsan [Children' s Hospital of Buffalo, NY (United States). Departments of Radiology and Pediatrics; Bommaraju, Mahesh [Women' s and Children' s Hospital of Buffalo, Division of Neonatology, University Pediatrics Associates, Buffalo, NY (United States)

    2006-09-15

    Tracheal agenesis is a rare and usually lethal anomaly. In the past, opaque contrast medium was injected via the esophagus to demonstrate the anatomy. To demonstrate the utility of helical and multidetector CT in delineating the aberrant anatomy in newborns with tracheal agenesis. Four newborns with tracheal agenesis were identified from three institutions. Imaging studies and medical records were reviewed. Each child was imaged with chest radiography. One child was imaged on a single-detector helical CT scanner and the other three on multidetector scanners. Helical and multidetector CT with 2D and 3D reconstructions clearly delineated the aberrant tracheobronchial and esophageal anatomy in each infant. Minimum intensity projection reformatted CT images were particularly helpful. One infant each had type I and type II tracheal agenesis. Two infants had type III tracheal agenesis. All four infants died. CT is a useful tool for delineating the aberrant anatomy of newborns with tracheal agenesis and thus helps in making rational clinical decisions. (orig.)

  18. The relevance of image quality indices for dose optimization in abdominal multi-detector row CT in children: experimental assessment with pediatric phantoms

    International Nuclear Information System (INIS)

    This study assessed and compared various image quality indices in order to manage the dose of pediatric abdominal MDCT protocols and to provide guidance on dose reduction. PMMA phantoms representing average body diameters at birth, 1 year, 5 years, 10 years and 15 years of age were scanned in a four-channel MDCT with a standard pediatric abdominal CT protocol. Image noise (SD, standard deviation of CT number), noise derivative (ND, derivative of the function of noise with respect to dose) and contrast-to-noise ratio (CNR) were measured. The 'relative' low-contrast detectability (rLCD) was introduced as a new quantity to adjust LCD to the various phantom diameters on the basis of the LCD1% assessed in a Catphan (registered) phantom and a constant central absorbed dose. The required variations of CTDIvol16 with respect to phantom size were analyzed in order to maintain each image quality index constant. The use of a fixed SD or CNR level leads to major dose ratios between extreme patient sizes (factor 22.7 to 44 for SD, 31.7 to 51.5 for CNR2.8%), whereas fixed ND and rLCD result in acceptable dose ratios ranging between factors of 2.9 and 3.9 between extreme phantom diameters. For a 5-9 mm rLCD1%, adjusted ND values range between -0.84 and -0.11 HU mGy-1. Our data provide guidance on dose reduction on the basis of patient dimensions and the required rLCD (e.g., to get a constant 7 mm rLCD1% for abdominal diameters of 10, 13, 16, 20 and 25 cm, tube current-time product should be adjusted in order to obtain CTDIvol16 values of 6.2, 7.2, 8.8, 11.6 and 17.7 mGy, respectively).

  19. Technical principles of dual source CT

    Energy Technology Data Exchange (ETDEWEB)

    Petersilka, Martin [Siemens Health Care, Forchheim (Germany)], E-mail: martin.petersilka@siemens.com; Bruder, Herbert; Krauss, Bernhard; Stierstorfer, Karl [Siemens Health Care, Forchheim (Germany); Flohr, Thomas G. [Siemens Health Care, Forchheim (Germany); Department of Diagnostic Radiology, Eberhard-Karls-Universitaet, Tuebingen (Germany)

    2008-12-15

    During the past years, multi-detector row CT (MDCT) has evolved into clinical practice with a rapid increase of the number of detector slices. Today's 64 slice CT systems allow whole-body examinations with sub-millimeter resolution in short scan times. As an alternative to adding even more detector slices, we describe the system concept and design of a CT scanner with two X-ray tubes and two detectors (mounted on a CT gantry with a mechanical offset of 90 deg.) that has the potential to overcome limitations of conventional MDCT systems, such as temporal resolution for cardiac imaging. A dual source CT (DSCT) scanner provides temporal resolution equivalent to a quarter of the gantry rotation time, independent of the patient's heart rate (83 ms at 0.33 s rotation time). In addition to the benefits for cardiac scanning, it allows to go beyond conventional CT imaging by obtaining dual energy information if the two tubes are operated at different voltages. Furthermore, we discuss how both acquisition systems can be used to add the power reserve of two X-ray tubes for long scan ranges and obese patients. Finally, future advances of DSCT are highlighted.

  20. Multislice Cardiac CT-Angiography; A Review on Accepted Indications and Potentials for Other Applications Regarding the Newest Development

    Directory of Open Access Journals (Sweden)

    M. Motevalli

    2007-05-01

    Full Text Available There were not any clear-cut criteria available for clinical use of cardiac CT-angiography (CCTA up to October 2006 in which the American College of Car-diology (ACC, American College of Radiology (ACR and six other medical institutions released a joint consensus on clinical indications of cardiac CT and MRI. A statement was released by the American Heart Association together with two other radiology and cardiology institutions in the same month on the same matter. An illustrated review will be presented on the newly accepted indications of cardiac CT, especially CCTA. Some prominent indications are as follow: 1. Evaluation of chest pain syndrome in patient with intermediate pretest probability of coronary artery disease (CAD when exercise test is not feasible. 2. Evaluation of acute chest pain in patient with in-termediate pretest probability of CAD and negative ECG and enzymes. 3. Uninterpretable or equivocal stress test (exercise, perfusion scan, or stress echo. 4. Evaluation of coronary arteries in patients with new onset heart failure. 5. Assessment of congenital coronary and cardiac anomalies. 6. Noninvasive coronary vein mapping prior to placement of biventricular pacemaker. 7. Noninvasive coronary arterial mapping, including internal mammary artery prior to repeat cardiac sur-gical revascularization. Some recent research indicated that CCTA is useful in some other specific situations too, like evaluating in-stent re-stenosis for stainless steel or cobalt stents more than 3mm in diameter and has also some roles in the evaluation of coronary bypass grafts, etc. Fi-nally, the newer progressions in the field of multislice CT are promising of even better performance which may widen the scope of its indications. Dual-source CT scanners have shown better performance com-pared with 64-slice CT scanners in the preliminary studies, namely slice-thickness of 0.25mm vs. 0.4mm, temporal resolution of 83ms vs.165ms, assessable segments of 98.6% vs. 97

  1. Banding and Step-Stair Artifacts on the Cardiac-CT Caused By Pseudo-Ectopic Beats

    OpenAIRE

    Singh, Amolak; Sethi, Yash; Watkins, Sonya; Youtsey, Angela; Thomas, Angie

    2009-01-01

    Step-stair and banding artifacts may result from irregular ventricular rhythm caused by atrial fibrillation or premature ectopic ventricular contractions. In the case reported here, severe banding and misalignment artifacts occurred due to electrocardiographic noise mimicking ectopic beats. Severe EKG noise or pseudo-ectopic beats may cause rare but serious artifacts during cardiac-CT acquisition. Vendor-provided software for correcting ectopic beats can be used to remove pseudo-ectopic beats...

  2. Bicuspid aortic valves: Diagnostic accuracy of standard axial 64-slice chest CT compared to aortic valve image plane ECG-gated cardiac CT

    Energy Technology Data Exchange (ETDEWEB)

    Murphy, David J., E-mail: david.murphy@st-vincents.ie [Department of Radiology, St Vincent' s University Hospital, Elm Park, Dublin 4 (Ireland); McEvoy, Sinead H., E-mail: s.mcevoy@st-vincents.ie [Department of Radiology, St Vincent' s University Hospital, Elm Park, Dublin 4 (Ireland); Iyengar, Sri, E-mail: sri.iyengar@nhs.net [Department of Radiology, Plymouth Hospitals NHS Trust, Plymouth Devon PL6 8DH (United Kingdom); Feuchtner, Gudrun, E-mail: Gudrun.Feuchtner@i-med.ac.at [Department of Radiology, Innsbruck Medical University, Anichstr. 35, A-6020 Innsbruck (Austria); Cury, Ricardo C., E-mail: r.cury@baptisthealth.net [Department of Radiology, Baptist Cardiac and Vascular Institute, 8900 North Kendall Drive, Miami, FL 33176 (United States); Roobottom, Carl, E-mail: carl.roobottom@nhs.net [Department of Radiology, Plymouth Hospitals NHS Trust, Plymouth Devon PL6 8DH (United Kingdom); Plymouth University Peninsula Schools of Medicine and Dentistry (United Kingdom); Baumueller, Stephan, E-mail: Hatem.Alkadhi@usz.ch [Institute for Diagnostic and Interventional Radiology, University Hospital Zurich, Raemistrasse 100, CH-8091 Zurich (Switzerland); Alkadhi, Hatem, E-mail: stephan.baumueller@usz.ch [Institute for Diagnostic and Interventional Radiology, University Hospital Zurich, Raemistrasse 100, CH-8091 Zurich (Switzerland); Dodd, Jonathan D., E-mail: jonniedodd@gmail.com [Department of Radiology, St Vincent' s University Hospital, Elm Park, Dublin 4 (Ireland)

    2014-08-15

    Objectives: To assess the diagnostic accuracy of standard axial 64-slice chest CT compared to aortic valve image plane ECG-gated cardiac CT for bicuspid aortic valves. Materials and methods: The standard axial chest CT scans of 20 patients with known bicuspid aortic valves were blindly, randomly analyzed for (i) the appearance of the valve cusps, (ii) the largest aortic sinus area, (iii) the longest aortic cusp length, (iv) the thickest aortic valve cusp and (v) valve calcification. A second blinded reader independently analyzed the appearance of the valve cusps. Forty-two age- and sex-matched patients with known tricuspid aortic valves were used as controls. Retrospectively ECG-gated cardiac CT multiphase reconstructions of the aortic valve were used as the gold-standard. Results: Fourteen (21%) scans were scored as unevaluable (7 bicuspid, 7 tricuspid). Of the remainder, there were 13 evaluable bicuspid valves, ten of which showed an aortic valve line sign, while the remaining three showed a normal Mercedes-Benz appearance owing to fused valve cusps. The 35 evaluable tricuspid aortic valves all showed a normal Mercedes-Benz appearance (P = 0.001). Kappa analysis = 0.62 indicating good interobserver agreement for the aortic valve cusp appearance. Aortic sinus areas, aortic cusp lengths and aortic cusp thicknesses of ≥3.8 cm{sup 2}, 3.2 cm and 1.6 mm respectively on standard axial chest CT best distinguished bicuspid from tricuspid aortic valves (P < 0.0001 for all). Of evaluable scans, the sensitivity, specificity, positive and negative predictive values of standard axial chest CT in diagnosing bicuspid aortic valves was 77% (CI 0.54–1.0), 100%, 100% and 70% respectively. Conclusion: The aortic valve is evaluable in approximately 80% of standard chest 64-slice CT scans. Bicuspid aortic valves may be diagnosed on evaluable scans with good diagnostic accuracy. An aortic valve line sign, enlarged aortic sinuses and elongated, thickened valve cusps are specific CT

  3. Investigation of saddle trajectories for cardiac CT imaging in cone-beam geometry

    Energy Technology Data Exchange (ETDEWEB)

    Pack, Jed D [Department of Radiology, University of Utah, Salt Lake City, UT 84112 (United States); Noo, Frederic [Department of Radiology, University of Utah, Salt Lake City, UT 84112 (United States); Kudo, H [Department of Computer Science, Graduate School of Systems and Information Engineering, University of Tsukuba (Japan)

    2004-06-07

    This paper investigates cone-beam tomography for a wide class of x-ray source trajectories called saddles. In particular, a mathematical analysis of the number of intersections between a saddle and an arbitrary plane is given. This analysis demonstrates that axially truncated cone-beam projections acquired along a saddle can be used for exact reconstruction at any point in a large volume. The reconstruction can be achieved either using a new algorithm presented herein or using a formula recently introduced by Katsevich (2003 Int. J. Math. Math. Sci. 21 1305-21). The shape of the reconstructed volume and the properties of saddles make saddles attractive for cardiac imaging. Three examples of saddles are presented with a discussion of implementation on devices similar to modern C-arm systems and multislice CT scanners. Reconstruction with one of these saddles has been tested using computer-simulated data, with and without truncation. The imaged phantom for the truncated data is a FORBILD head phantom (representing the heart) that has been modified and embedded inside the FORBILD thorax phantom. The non-truncated data were generated by excluding the thorax. The reconstructed images demonstrate the accuracy of the mathematical results.

  4. A direct comparison of the sensitivity of CT and MR cardiac perfusion using a myocardial perfusion phantom

    Science.gov (United States)

    Otton, James; Morton, Geraint; Schuster, Andreas; Bigalke, Boris; Marano, Riccardo; Olivotti, Luca; Nagel, Eike; Chiribiri, Amedeo

    2013-01-01

    Background Direct comparison of CT and magnetic resonance (MR) perfusion techniques has been limited and in vivo assessment is affected by physiological variability, timing of image acquisition, and parameter selection. Objective We precisely compared high-resolution k-t SENSE MR cardiac perfusion at 3 T with single-phase CT perfusion (CTP) under identical imaging conditions. Methods We used a customized MR imaging and CT compatible dynamic myocardial perfusion phantom to represent the human circulation. CT perfusion studies were performed with a Philips iCT (256 slice) CT, with isotropic resolution of 0.6 mm3. MR perfusion was performed with k-t SENSE acceleration at 3 T and spatial resolution of 1.2 × 1.2 × 10 mm. The image contrast between normal and underperfused myocardial compartments was quantified at various perfusion and photon energy settings. Noise estimates were based on published clinical data. Results Contrast by CTP highly depends on photon energy and also timing of imaging within the myocardial perfusion upslope. For an identical myocardial perfusion deficit, the native image contrast-to-noise ratio (CNR) generated by CT and MR are similar. If slice averaging is used, the CNR of a perfusion deficit is expected to be greater for CTP than MR perfusion (MRP). Perfect timing during single time point CTP imaging is difficult to achieve, and CNR by CT decreases by 24%–31% two seconds from the optimal imaging time point. Although single-phase CT perfusion offers higher spatial resolution, MRP allows multiple time point sampling and quantitative analysis. Conclusion The ability of CTP and current optimal MRP techniques to detect simulated myocardial perfusion deficits is similar. PMID:23622506

  5. Preoperative volume calculation of the hepatic venous draining areas with multi-detector row CT in adult living donor liver transplantation: impact on surgical procedure

    Energy Technology Data Exchange (ETDEWEB)

    Frericks, Bernd B.J. [Hanover Medical School, Departments of Radiology and Surgery, Hannover (Germany); University of Berlin, Department of Radiology, Berlin (Germany); Charite - University Medicine Berlin, Department of Radiology and Nuclear Medicine, Berlin (Germany); Kirchhoff, Timm D.; Shin, Hoen-Oh; Stamm, Georg; Merkesdal, Sonja; Abe, Takehiko; Galanski, Michael [Hanover Medical School, Departments of Radiology and Surgery, Hannover (Germany); Hanover Medical School, Department of Diagnostic Radiology, Hannover (Germany); Schenk, Andrea; Peitgen, Heinz-Otto [Hanover Medical School, Departments of Radiology and Surgery, Hannover (Germany); MeVis - Center for Medical Diagnostic Systems and Visualization, Bremen (Germany); Klempnauer, Juergen [Hanover Medical School, Departments of Radiology and Surgery, Hannover (Germany); Hanover Medical School, Department of Visceral- and Transplantation Surgery, Hannover (Germany); Nashan, Bjoern [Hanover Medical School, Departments of Radiology and Surgery, Hannover (Germany); Hanover Medical School, Department of Visceral- and Transplantation Surgery, Hannover (Germany); Dalhousie University, Multi Organ Transplant Program, Halifax, Nova Scotia (Canada)

    2006-12-15

    The purpose was to assess the volumes of the different hepatic territories and especially the drainage of the right paramedian sector in adult living donor liver transplantation (ALDLT). CT was performed in 40 potential donors of whom 28 underwent partial living donation. Data sets of all potential donors were postprocessed using dedicated software for segmentation, volumetric analysis and visualization of liver territories. During an initial period, volumes and shapes of liver parts were calculated based on the individual portal venous perfusion areas. After partial hepatic congestion occurring in three grafts, drainage territories with special regard to MHV tributaries from the right paramedian sector, and the IRHV were calculated additionally. Results were visualized three-dimensionally and compared to the intraoperative findings. Calculated graft volumes based on hepatic venous drainage and graft weights correlated significantly (r=0.86,P<0.001). Mean virtual graft volume was 930 ml and drained as follows: RHV: 680 ml, IRHV: 170 ml (n=11); segment 5 MHV tributaries: 100 ml (n=16); segment 8 MHV tributaries: 110 ml (n=20). When present, the mean aberrant venous drainage fraction of the right liver lobe was 28%. The evaluated protocol allowed a reliable calculation of the hepatic venous draining areas and led to a change in the hepatic venous reconstruction strategy at our institution. (orig.)

  6. Atherosclerotic plaque volume and composition in symptomatic carotid arteries assessed with multidetector CT angiography; relationship with severity of stenosis and cardiovascular risk factors

    International Nuclear Information System (INIS)

    The purpose of this study was to examine the volume and the composition of atherosclerotic plaque in symptomatic carotid arteries and to investigate the relationship between these plaque features and the severity of stenosis and the presence of cardiovascular risk factors. One hundred patients with cerebrovascular symptoms underwent CT angiography. We measured plaque volume (PV) and the relative contribution of plaque components (calcifications, fibrous tissue, and lipid) in the symptomatic artery. The contribution of different components was measured as the number of voxels within defined ranges of HU values (calcification >130 HU, fibrous tissue 60-130 HU, lipid core <60 HU). Fifty-seven patients had atherosclerotic plaque in the symptomatic carotid artery. The severity of stenosis and PV were moderately correlated. Age and smoking were independently related to PV. Patients with hypercholesterolemia had significantly less lipid and more calcium in their plaques than patients without hypercholesterolemia. Other cardiovascular risk factors were not significantly related to PV or plaque composition. Luminal stenosis of the carotid artery partly reflects the amount of atherosclerotic carotid disease. Plaque volume and plaque composition are associated with cardiovascular risk factors. (orig.)

  7. Atherosclerotic plaque volume and composition in symptomatic carotid arteries assessed with multidetector CT angiography; relationship with severity of stenosis and cardiovascular risk factors

    Energy Technology Data Exchange (ETDEWEB)

    Rozie, S.; Weert, T.T. de; Monye, C. de; Homburg, P.J.; Tanghe, H.L.J.; Lugt, A. van der [Erasmus MC, University Medical Center Rotterdam, Departments of Radiology, Rotterdam (Netherlands); Dippel, D.W.J. [Erasmus MC, University Medical Center Rotterdam, Department of Neurology, PO Box 2040, Rotterdam (Netherlands)

    2009-09-15

    The purpose of this study was to examine the volume and the composition of atherosclerotic plaque in symptomatic carotid arteries and to investigate the relationship between these plaque features and the severity of stenosis and the presence of cardiovascular risk factors. One hundred patients with cerebrovascular symptoms underwent CT angiography. We measured plaque volume (PV) and the relative contribution of plaque components (calcifications, fibrous tissue, and lipid) in the symptomatic artery. The contribution of different components was measured as the number of voxels within defined ranges of HU values (calcification >130 HU, fibrous tissue 60-130 HU, lipid core <60 HU). Fifty-seven patients had atherosclerotic plaque in the symptomatic carotid artery. The severity of stenosis and PV were moderately correlated. Age and smoking were independently related to PV. Patients with hypercholesterolemia had significantly less lipid and more calcium in their plaques than patients without hypercholesterolemia. Other cardiovascular risk factors were not significantly related to PV or plaque composition. Luminal stenosis of the carotid artery partly reflects the amount of atherosclerotic carotid disease. Plaque volume and plaque composition are associated with cardiovascular risk factors. (orig.)

  8. 多排螺旋CT 诊断小网膜囊病变的价值%Diagnostic value of multi-detector CT for abnormalities in lesser omental bursa

    Institute of Scientific and Technical Information of China (English)

    成峰; 吴凯宏; 李孝虎

    2011-01-01

    目的 探讨小网膜囊正常解剖及病变的多排螺旋CT(MDCT)表现,评价小网膜囊病变的CT 诊断价值.方法 对24 例小网膜囊病变进行上腹部CT 平扫及三期增强扫描检查,均经手术病理证实.结果 小网膜囊病变中:原发肿瘤6 例(神经鞘瘤2 例,平滑肌瘤1 例,血管瘤1 例,脂肪肉瘤1 例,淋巴瘤1 例),CT 表现为小网膜囊内边界清晰肿块.邻近脏器的良、恶性肿瘤8 例(胰头癌4 例,肝左叶肝细胞癌2 例,胃间质瘤2 例),CT 表现为小网膜囊肿块与邻近相应肿瘤边界不清.转移性肿瘤2 例.结核1 例,CT 表现多个病灶融合,内见钙化.积液(腹水漏出液、炎性渗出液、脓液、血液、胆汁、淋巴液)6 例;假性囊肿1 例;CT 均表现为小网膜囊内液性密度灶.结论 多排螺旋CT对小网膜囊病变具有重要的诊断价值.%Objective To investigate the normal CT anatomy and diagnostic value of CT for abnormalities of lesser omental bursa. Methods Twenty-four patients with 6 primary neoplasms (2 neurinomas, 1 leiomyoma, 1 cavernous hemangioma, 1 liposarcoma, 1 lymphoma), 8 local spread from adjacent benign or malignant neoplasms (4 carcinomas of head of pancreas, 2 left hepatic tumors, 2 gastrointestinal stromal tumors of the stomach), 2 metastatic tumors, 1 tuberculosis, 6 fluid collections (transudate ascites, inflammatory infiltrate, pus, blood, bile, lymph), lpseudocyst were enrolled in the study. All of the lesions were confirmed by operation and pathology. The pre- and post-contrast abdominal CT scans were reviewed. Results The borders of the 6 primary neoplasms were well-defined on CT whereas the 8 benign or malignant neoplasms originating from adjacent structures were contiguous with the primary tumors. CT showed multiple aggregated lesions on 2 patients with metastases and 1 patient with tuberculosis. The 6 fluid collections and lpseudocyst displayed fluid density within lesser omental bursa on CT. Conclusion CT is valuable in

  9. Children's (Pediatric) CT (Computed Tomography)

    Medline Plus

    Full Text Available ... over time. top of page What are the benefits vs. risks? Benefits Using a multidetector CT unit to examine children ... that will provide the needed diagnostic information. The benefit of an accurate diagnosis far outweighs the risk. ...

  10. Children's (Pediatric) CT (Computed Tomography)

    Medline Plus

    Full Text Available ... over time. top of page What are the benefits vs. risks? Benefits Using a multidetector CT unit to examine children ... the possible charges you will incur. Web page review process: This Web page is reviewed regularly by ...

  11. Automatic selection of optimal cardiac-phase in coronary CT angiography. Its clinical usefulness for patients with atrial fibrillation

    International Nuclear Information System (INIS)

    The optimal cardiac phases for coronary CT angiography (CTA) are end-systole and mid-diastole, in which cardiac movement is slow. In conventional methods, these cardiac phases are determined by visual selection. We have compared the images in the optimal cardiac phases that were selected by the conventional method and cardiac-phase search software (Phase Navi), and examined the clinical usefulness of Phase Navi in patients with atrial fibrillation. The subjects were 38 patients (regular rhythm: 20, atrial fibrillation: 18). The continuity scores of patients with regular rhythm (Phase Navi, conventional methods) were 2.4±0.3-2.5±0.3 in end-systole and 2.4±0.5-2.4±0.4 in mid-diastole. The scores of patients with atrial fibrillation (Phase Navi, conventional methods) were 2.3±0.4-2.3±0.4 in end-systole, and 2.2±0.5-2.1±0.6 in mid-diastole. Because the continuity scores of the optimal images from Phase Navi were similar to those from the conventional method, Phase Navi had clinical usefulness in patients with atrial fibrillation. (author)

  12. A knowledge-based method for reducing attenuation artefacts caused by cardiac appliances in myocardial PET/CT

    Energy Technology Data Exchange (ETDEWEB)

    Hamill, James J [Siemens Medical Solutions, Molecular Imaging, 810 Innovation Dr., Knoxville, TN (United States); Brunken, Richard C [Department of Molecular and Functional Imaging, Cleveland Clinic Foundation, 9500 Euclid Ave., Cleveland, OH (United States); Bybel, Bohdan [Department of Molecular and Functional Imaging, Cleveland Clinic Foundation, 9500 Euclid Ave., Cleveland, OH (United States); DiFilippo, Frank P [Department of Molecular and Functional Imaging, Cleveland Clinic Foundation, 9500 Euclid Ave., Cleveland, OH (United States); Faul, David D [Siemens Medical Solutions, Molecular Imaging, 810 Innovation Dr., Knoxville, TN (United States)

    2006-06-07

    Attenuation artefacts due to implanted cardiac defibrillator leads have previously been shown to adversely impact cardiac PET/CT imaging. In this study, the severity of the problem is characterized, and an image-based method is described which reduces the resulting artefact in PET. Automatic implantable cardioverter defibrillator (AICD) leads cause a moving-metal artefact in the CT sections from which the PET attenuation correction factors (ACFs) are derived. Fluoroscopic cine images were measured to demonstrate that the defibrillator's highly attenuating distal shocking coil moves rhythmically across distances on the order of 1 cm. Rhythmic motion of this magnitude was created in a phantom with a moving defibrillator lead. A CT study of the phantom showed that the artefact contained regions of incorrect, very high CT values and adjacent regions of incorrect, very low CT values. The study also showed that motion made the artefact more severe. A knowledge-based metal artefact reduction method (MAR) is described that reduces the magnitude of the error in the CT images, without use of the corrupted sinograms. The method modifies the corrupted image through a sequence of artefact detection procedures, morphological operations, adjustments of CT values and three-dimensional filtering. The method treats bone the same as metal. The artefact reduction method is shown to run in a few seconds, and is validated by applying it to a series of phantom studies in which reconstructed PET tracer distribution values are wrong by as much as 60% in regions near the CT artefact when MAR is not applied, but the errors are reduced to about 10% of expected values when MAR is applied. MAR changes PET image values by a few per cent in regions not close to the artefact. The changes can be larger in the vicinity of bone. In patient studies, the PET reconstruction without MAR sometimes results in anomalously high values in the infero-septal wall. Clinical performance of MAR is assessed by

  13. Coronary artery assessment by multidetector computed tomography in patients with prosthetic heart valves

    NARCIS (Netherlands)

    Habets, Jesse; van den Brink, Renee B. A.; Uijlings, Ruben; Spijkerboer, Anje M.; Mali, Willem P. Th. M.; Chamuleau, Steven A. J.; Budde, Ricardo P. J.

    2012-01-01

    Objectives Patients with prosthetic heart valves may require assessment for coronary artery disease. We assessed whether valve artefacts hamper coronary artery assessment by multidetector CT. Methods ECG-gated or -triggered CT angiograms were selected from our PACS archive based on the presence of p

  14. A novel method for incorporating respiratory-matched attenuation correction in the motion correction of cardiac PET-CT studies

    Science.gov (United States)

    McQuaid, Sarah J.; Lambrou, Tryphon; Hutton, Brian F.

    2011-05-01

    Mismatches between PET and CT datasets due to respiratory effects can lead to artefactual perfusion defects. To overcome this, we have proposed a method of aligning a single CT with each frame of a gated PET study in a semi-automatic manner, incorporating a statistical shape model of the diaphragm and a rigid registration of the heart. This ensures that the structures that could influence the appearance of the reconstructed cardiac activity are correctly matched between emission and transmission datasets. When tested on two patient studies, it was found in both cases that attenuation correction using the proposed technique resulted in PET images that were closer to the gold standard of attenuation correction with a gated CT, compared with scenarios where only heart matching was considered (and not the diaphragm) or where no transformation was performed (i.e. where a single CT frame was used to attenuation-correct all PET frames). These preliminary results suggest that diaphragm matching between PET and CT improves the quantitative accuracy of reconstructed PET images and that the proposed method of using a statistical shape model to describe the diaphragm shape and motion, in combination with a rigid registration to determine respiratory-induced heart motion, is a feasible method of achieving this.

  15. Correlation of CT-based regional cardiac function (SQUEEZ) with myocardial strain calculated from tagged MRI: an experimental study.

    Science.gov (United States)

    Pourmorteza, Amir; Chen, Marcus Y; van der Pals, Jesper; Arai, Andrew E; McVeigh, Elliot R

    2016-05-01

    The objective of this study was to investigate the correlation between local myocardial function estimates from CT and myocardial strain from tagged MRI in the same heart. Accurate detection of regional myocardial dysfunction can be an important finding in the diagnosis of functionally significant coronary artery disease. Tagged MRI is currently a reference standard for noninvasive regional myocardial function analysis; however, it has practical drawbacks. We have developed a CT imaging protocol and automated image analysis algorithm for estimating regional cardiac function from a few heartbeats. This method tracks the motion of the left ventricular (LV) endocardial surface to produce local function maps: we call the method Stretch Quantification of Endocardial Engraved Zones (SQUEEZ). Myocardial infarction was created by ligation of the left anterior descending coronary artery for 2 h followed by reperfusion in canine models. Tagged and cine MRI scans were performed during the reperfusion phase and first-pass contrast enhanced CT scans were acquired. The average delay between the CT and MRI scans was myocardial strain (Ecc) was calculated from the tagged MRI data. The agreement between peak systolic Ecc and SQUEEZ was investigated in 162 segments in the 9 hearts. Linear regression and Bland-Altman analysis was used to assess the correlation between the two metrics of local LV function. The results show good agreement between SQUEEZ and Ecc: (r = 0.71, slope = 0.78, p function. The good agreement between the estimates of local myocardial function obtained from CT SQUEEZ and tagged MRI provides encouragement to investigate the use of SQUEEZ for measuring regional cardiac function at a low clinical dose in humans.

  16. The Comparative Study of Multidetector Spiral CT Reconstruction and Endoscope in Diagnosing Polyp Intestinal%MDCT多平面重组技术诊断肠息肉与内镜对比分析

    Institute of Scientific and Technical Information of China (English)

    罗敏; 殷磊; 马明平; 范建中; 杜瑞宾

    2011-01-01

    目的 探讨多排螺旋CT(MDCT)对肠息肉的显示情况及良恶性诊断正确性.资料与方法 经病理证实的33例(按解剖部位共54例)肠息肉患者均行内镜及MDCT平扫和双期增强扫描,回顾性分析并比较两种检查对不同部位肠息肉的检出情况和MDCT对肠息肉良恶性的诊断情况.结果 MDCT共检出肠息肉54例,其中小肠3例(均位于空肠),结肠38例(升结肠回盲部6例,横结肠4例,降结肠9例,乙状结肠19例),直肠13例.CT拟诊良性46例,恶性8例,病理证实5例恶变,恶性诊断正确率为62.5%(5/8).内镜共检出48例,3例胃癌术后吻合口远端空肠小息肉均漏诊,1例回盲部小息肉、2例直肠远端小息肉均漏诊.结论 MDCT多平面重组图像结合双期增强薄层轴位图像能准确检出不同解剖部位的肠息肉,对肠息肉的检出优于内镜;对预测息肉有无恶变及随访复查有重要的临床价值.%Objective To investigate the value of multidetector Spiral CT(MDCT) in diagnosing polyp intestinal. Materials and Methods 33 cases with polyp intestinal(54 cases by anatomic site)proved by pathology received endoscope and plain and two-phase enhanced MDCT scan. Detection of polyp intestinal and diagnostic accuracy of benign or malignant by two examinations were analyzed and compared respectively. Results Among 54 cases with polyp intestinal detected by MDCT, there were 3 cases with polyp intestinal in small intestine( all in jejunum) ;38 cases in colon(6 in ascending colon and junction,4 in transverse colon,9 in descending colon, 19 in sigmoid colon) ;13 cases in rectum. There were 46 cases with polyp intestinal were benign and 8 cases were malignant by MDCT, while 5 were confirmed by pathology, the diagnostic accuracy of malignant was 62.5%. 48 cases were detected by endoscope,3 cases with small jejunum polyp in distal end of stoma after gastric carcinoma were missed, 1 case with small polyp in ileocecal junction and 2 cases with small polyp

  17. Hereditary haemorrhagic telangiectasia: study of hepatic vascular alterations with multi-detector row helical CT and reconstruction programs; Telangiectasia emorragica ereditaria: TC multidetettore multifasica e programmi di ricostruzione nello studio delle alterazioni vascolari epatiche

    Energy Technology Data Exchange (ETDEWEB)

    Memeo, Maurizio; Stabile Ianora, Amato Antonio; Scaldapane, Arnaldo; Rotondo, Antonio; Angelelli, Giuseppe [Policlinico Universitario, Bari (Italy). DiMIMP Sezione di Diagnostica per Immagini; Suppressa, Patrizia; Cirulli, Anna; Sabba' , Carlo [Policlinico Universitario, Bari (Italy). Centro Interdipartimentale per lo studio dell' HHT

    2005-02-01

    Purpose: To evaluate hepatic alterations in patients affected by Hereditary Haemorrhagic Telangiectasia (HHT) by using multidetector row helical CT (MDCT) and new reconstruction programs. Materials and methods: An MDCT multiphasic study of the liver was performed in 105 consecutive patients: 89 considered to be affected by HHT and 16 with suspicion of disease alone. The scan delay was determined by using a test bolus of contrast material. The CT examination was performed with a triphasic technique (double arterial phase and portal venous phase). multiplanar and angiographic reconstructions were then obtained, and the images checked for the presence of shunts, hepatic perfusion disorders, vascular lesions (telangiectasis and large confluent vascular masses), indirect signs of portal hypertension, and anatomical vascular variants. Results: Hepatic vascular alterations were found in 78/105 cases (67/89) patients affected by HHT and 11/16 patients with clinical suspicion alone). Therefore HHT diagnosis was excluded in 5 patients. 78/100 (78%) patients with HHT had intrahepatic vascular alterations: arterioportal shunts in 40/78 (51.2%) arteriosystemic shunts in 16/78 (20.5%) and both shunt types in 22/78 (28.3%). Intraparenchymal perfusion disorders were found in 46/78 (58.9%) patients. Telangiectasis were recognised in 50/78 (64.1%) patients. Large confluent vascular masses (LCVMs) were identified in 20/78 (25.6%) patients. indirect signs of portal hypertension were found in 46/78 (58.9%) cases. Variant hepatic arterial anatomy was present in 38/100 cases (38%). Conclusions: Multiphasic MDCT and the new reconstruction programs enable the identification and characterisation of the complex vascular alterations typical of HHT. [Italian] Scopo: Valutare le alterazioni epatiche nei pazienti affetti da Telangiectasia Emorraica Ereditaria (TEE) utilizzando una TC multidetettore (TCMD) ed in nuovi programmi di ricostruzione. Materiale e metodi: E' stato eseguito uno

  18. Low radiation dose non-contrast cardiac CT: is it of value in the evaluation of mechanical aortic valve

    Energy Technology Data Exchange (ETDEWEB)

    Bazeed, Mohamed Fayez (Dept. of Diagnostic Radiology, Faculty of Medicine, Mansoura Univ. (Egypt)), email: m_bazeed@yahoo.com; Moselhy, Mohamed Saleh (Cardiology Dept. Faculty of Medicine, Suez Canal Univ. (Egypt)); Rezk, Ahmad Ibrahim (Dept. of Cardiac Surgery, Faculty of Medicine, Aim Shams Univ. (Egypt)); Al-Murayeh, Mushabab Ayedh (Dept. of Cardiac Services, Armed Forces Hospitals Southern Region (Saudi Arabia))

    2012-05-15

    Background: Prosthetic bileaflet mechanical valve function has been traditionally evaluated using echocardiography and fluoroscopy. Multidetector computed tomography (MDCT) is a novel technique for cardiac evaluation. Purpose: To evaluate bileaflet mechanical aortic valves using a low-milliampere (mA), non-contrast MDCT protocol with a limited scan range. Material and Methods: Forty patients with a bileaflet mechanical aortic valve were evaluated using a non-contrast, low-mA, ECG-gated 64 MDCT protocol with a limited scan range. MDCT findings of opening and closing valve angles were correlated to fluoroscopy and echocardiography. Also, the valve visibility was evaluated on MDCT and fluoroscopy according to a 3-point grading scale. Results: The visualization score with the MDCT was significantly superior to the fluoroscopy (3 vs. 2.7). A strong correlation was noted between the opening (r = 0.82) and closing (r = 0.96) valve angles with MDCT and fluoroscopy without a statistically significant difference (P = 0.31 and 0.16, respectively). The mean effective radiation dose of the suggested protocol was 4 +- 0.5 mSv. Five valves were evaluated using transesophageal echocardiography because the valves were difficult to evaluate with transthoracic echocardiography, and all of these valves were evaluated optimally with MDCT. A high-pressure gradient was noted in nine valves, and the MDCT showed that seven of these valves inadequately opened, and two valves opened well, which resulted in patient valve mismatch. Incomplete valve closure was noted in five valves, and the echocardiography showed significant transvalvular regurgitation in all five valves. Conclusion: MDCT can provide a precise measurement of valve function and can potentially evaluate high-pressure gradients and transvalvular regurgitation

  19. Venous thromboembolic disease. CT evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Goodman, L. R. [Medical College of Wisconsin, Pulmonary Medicine and Intensive Care, Dept. of Diagnostic Radiology, Milwaukee, WI (United States)

    2001-12-01

    Helical and multidetector CT has proven to be a valuable imaging modality for both pulmonary embolism and deep venous thrombosis. This paper will review the sensitivity and specificity of CT and discuss diagnostic algorithms utilizing CT and more established imaging technologies.

  20. Quantification of myocardial delayed enhancement and wall thickness in hypertrophic cardiomyopathy: Multidetector computed tomography versus magnetic resonance imaging

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Lei [Department of Radiology, Beijing Anzhen Hospital, Capital Medical University, No. 2 Anzhen Rd Beijing (China); Ma, Xiaohai, E-mail: maxi8238@gmail.com [Department of Radiology, Beijing Anzhen Hospital, Capital Medical University, No. 2 Anzhen Rd Beijing (China); Feuchtner, Gudrun Maria [Department of Radiology II, Innsbruck Medical University, Innsbruck (Austria); Zhang, Chen; Fan, Zhanming [Department of Radiology, Beijing Anzhen Hospital, Capital Medical University, No. 2 Anzhen Rd Beijing (China)

    2014-10-15

    Objectives: To evaluate the accuracy of multidetector computed tomography (MDCT) in assessing myocardial delayed enhancement and left ventricle wall thickness in hypertrophic cardiomyopathy (HCM) compared with cardiac magnetic resonance (CMR) as the reference standard. Materials and methods: Eighty consecutive patients (59 male; 53.2 ± 13.0 years) were examined with MDCT, followed by CMR 1 day later. Cardiac CT angiography and a delayed CT were performed. CMR was performed according to a standardized protocol. Left ventricle wall thickness and positions of myocardial delayed enhancement were identified in both CMR and CT images according to the American Heart Association left ventricle 17-segment model. Myocardial delayed enhancement was characterized as “dense” (areas with clear defined borders) or “diffuse” and then quantified using both techniques. Results: Left ventricle wall thickness determined by MDCT was significantly correlated with CMR (R = 0.88, P < 0.01). Compared with CMR, MDCT accurately diagnosed 74 of 78 (94.9%) patients and 1243 of 1326 (93.7%) segments. For dense myocardial delayed enhancement, MDCT significantly correlated with CMR (R = 0.88, P < 0.01) and slightly underestimated myocardial delayed enhancement (mean, −3.85%; lower and upper limits of agreement, −13.40% and 5.70%, respectively). Conclusions: MDCT provides reliable quantification of myocardial delayed enhancement and evaluation of left ventricle wall thickness and has a good correlation with CMR in patients with HCM when a comprehensive cardiac CT protocol is used and can be applied for intervention planning.