Sample records for 64-slice multi-detector computed

  1. Serial changes of coronary atherosclerotic plaque: Assessment with 64-slice multi-detector computed tomography

    Kim, Eun Young; Kang, Doo Kyoung; Sun, Joo Sung; Choi, So Yeon [Ajou University School of Medicine, Suwon (Korea, Republic of)


    Evaluate the progression of coronary atherosclerotic plaque during follow-up, and its association with cardiovascular risk factors. Fifty-six atherosclerotic patients with plaque were enrolled in this retrospective study. Patient's plaque was detected on repeat 64-slice multidetector CT scans with a mean interval of 25 ± 10 months changes in calcified and non-calcified plaque volumes and cardiovascular risk factors were assessed over time. Absolute and relative changes in plaque volume were compared, and the association between rapid progression and cardiovascular risk factors was determined. Diameter of the stenosis, length, calcified and non-calcified lesion plaque volumes increased significantly on follow-up CT. Absolute and relative annual changes in plaque volumes were significantly greater in non-calcified plaque (median, 22.7 mm{sup 3}, 90.4%) than in calcified plaque (median, 0.7 mm{sup 3}, 0%). Obesity, smoking, hypertension, hypercholesterolemia, and low high-density lipoprotein were significant predictors of progression of non-calcified plaque. Progression of calcified plaque was not associated with any cardiovascular risk factors. Coronary plaque volume increased significantly on follow-up CT. The rate of progression is related to non-calcified plaque than to calcified plaque. Cardiovascular risk factors are independently associated with the rapid progression of non-calcified plaque volume, but not associated with the progression of calcified plaque.

  2. CT angiography of pulmonary embolism using a 64 slice multi-detector scanner

    QIN Nai-shan; JIANG Xue-xiang; QIU Jian-xing; ZHU Ying; WANG Ji-chen


    Background Multi-detector computed tomography (MDCT) has already been the first line investigation method for diagnosis of pulmonary embolism (PE). Reducing the amount of contrast medium used during CT scanning could decrease the incidental rate of adverse reactions. Our study amied to evaluate the image quality of pulmonary arteries using 64 slice multi-detector CT with small volumes of contrast media injection.Methods Forty nonconsecutive patients without PE or other lung diseases were randomly assigned to two groups.Group A underwent CT scanning with 16×1.25 mm collimation and a 70 ml contrast injection, while group B had CT with 64×0.625 mm collimation and 20 ml of contrast injection. Two readers independently depicted the segmental and subsegmental pulmonary arteries. Reasons we could not analyze the pulmonary artery or that led to misdiagnosis of pulmonary embolism were evaluated, including the degree of contrast enhancement of the main pulmonary artery, and factors that caused misdiagnosis of PE (flow-related artifacts, partial volume artifact, beam-hardening artifacts and enhancement of pulmonary vein). The independent samples t-test, Mann-Whitney U test and Pearson chi-square test were applied.Results There were no significant differences in image quality of segmental and subsegmental arteries between the two groups. No significant difference was found for factors that made pulmonary arteries non-analyzable or in the misdiagnosis of PE, except the degree of contrast enhancement.Conclusion 64×0.625 mm collimation with 20 ml contrast injection could depict the pulmonary arteries well.

  3. Assessment of Coronary Stents by 64-slice Computed Tomography:In-stent Lumen Visibility and Patency

    Ling-yan Kong; Zheng-yu Jin; Shu-yang Zhang; Zhu-hua Zhang; Yi-ning Wang; Lan Song; Xiao-na Zhang; Yun-qing Zhang


    Objective To assess lumen visibility of coronary stents by 64-slice computed tomography(CT)coronary angiography,and determine the value of 64-slice CT in non-invasive detecting of in-stent restenosis after coronary artery stent implantation.Methods Totally,60 patients(54 males,aged 57.0±12.7 years)and 105 stents were investigated by 64-slice CT at a mean interval of 20.0±16.6 months after coronary stents implantation.Axial multi-planar reconstruction images of the stents and curved-planar reconstruction images through the median of the stents were reconstructed for evaluating stent image quality on a 5-point scale(1=excellent,5=nonassessable),and stent lumen diameter was detected.Conventional coronary angiography was performed in 18 patients,and 32 stents were evaluated.Results Image quality was good to excellent on average(score 1.71±0.76).Stent image quality score was correlated to heart rate(r=0.281,P<0.01)and stent diameter(r=0.480,P<0.001).All the stents were assessable in lumen visibility with an average visible lumen diameter percentage of 60.7% ±13.6% .Visible lumen diameter percentage was correlated to heart rate(r=-0.193,P<0.05),stent diameter (r=0.403,P<0.001),and stent image quality score(r=-0.500,P<0.001).Visible lumen diameter percentage also varied depending on the stent type.In comparison with the conventional coronary angiography,4 of 6 in-stent stenoses were correctly detected.The sensitivity and specificity for the detection of in-stent stenosis were 66.7% and 84.6% ,respectively.Conclusions Using a 64-slice CT,the stent lumen is partly visible in most of the stents.And 64-slice CT may be useful in the assessment of stent patency.

  4. Influence of cardiac hemodynamic parameters on coronary artery opacification with 64-slice computed tomography

    Husmann, Lars; Alkadhi, Hatem; Boehm, Thomas; Leschka, Sebastian; Desbiolles, Lotus; Marincek, Borut [University Hospital of Zurich, Department of Medical Radiology, Institute of Diagnostic Radiology, Zurich (Switzerland); Schepis, Tiziano; Koepfli, Pascal; Wildermuth, Simon [University Hospital of Zurich, Cardiovascular Center, Zurich (Switzerland); Kaufmann, Philipp A. [University Hospital of Zurich, Cardiovascular Center, Zurich (Switzerland); University of Zurich, Center for Integrative Human Physiology, Zurich (Switzerland)


    The purpose of this study was to evaluate the influence of ejection fraction (EF), stroke volume (SV), heart rate, and cardiac output (CO) on coronary artery opacification with 64-slice computed tomography (CT). Sixty patients underwent, retrospectively, electrocardiography-gated 64-slice CT coronary angiography. Left ventricular EF, SV, and CO were calculated with semi-automated software. Attenuation values were measured and contrast-to-noise ratios (CNRs) were calculated in the proximal right coronary artery (RCA) and left main artery (LMA). Mean EF during scanning was 61.5{+-}12.4%, SV was 63.2{+-}15.6 ml, heart rate was 62.5{+-}11.8 beats per minute (bpm), and CO was 3.88{+-}1.06 l/min. There was no significant correlation between the EF and heart rate and the attenuation and CNR in either coronary artery. A significant negative correlation was found in both arteries between SV and attenuation (RCA r=-0.26, P<0.05; LMA r=-0.34, P<0.01) and between SV and CNR (RCA r=-0.26, P<0.05; LMA r=-0.26, P<0.05). Similarly, a significant negative correlation was found between the CO and attenuation (RCA r=-0.42, P<0.05; LMA r=-0.56, P<0.001) and between the CO and CNR (RCA r=-0.39, P<0.05; LMA r=-0.44, P<0.001). The actual hemodynamic status of the patient influences the coronary artery opacification with 64-slice CT, in that vessel opacification decreases as SV and CO increase. (orig.)

  5. Influence of coronary calcification on the diagnostic accuracy of 64-slice computed tomography coronary angiography

    Abdulla, Jawdat; Pedersen, Kasper; Budoff, Matthew;


    To determine via meta-analysis the diagnostic accuracy of 64-slice computed tomography coronary angiography (CTA) for assessment of significant obstructive coronary artery stenosis at different coronary artery calcium score (CACS) levels. Data of 12,053 versus 5,890 segments, 906 versus 758...... arteries and 1,120 versus 514 patients in low versus high CACS subgroups from 19 eligible studies were compared. The per-patient prevalence of coronary artery disease was 48% versus 68%, respectively. Subgroups were stratified by different CACS thresholds ranging from 100 to 400. Meta-analyses of per......-patient data comparing overall low versus high CACS subgroups resulted in a sensitivity of 97.5 (95.5-99)% versus 97 (94.5-98.5)%, specificity of 85 (82-88)% versus 66.5 (58-74.5)%, diagnostic odds ratio of 153 (81-290) versus 40 (20-83), positive predictive value of 85 (82-87)% versus 86 (84-88)%, negative...

  6. Coronary artery stent geometry and in-stent contrast attenuation with 64-slice computed tomography

    Schepis, Tiziano; Koepfli, Pascal; Gaemperli, Oliver; Eberli, Franz R.; Luescher, Thomas F. [University Hospital Zurich, Cardiovascular Center, Zurich (Switzerland); Leschka, Sebastian; Desbiolles, Lotus; Husmann, Lars; Wildermuth, Simon; Marincek, Borut; Alkadhi, Hatem [University Hospital Zurich, Institute of Diagnostic Radiology, Zurich (Switzerland); Kaufmann, Philipp A. [University Hospital Zurich, Cardiovascular Center, Zurich (Switzerland); Zurich Center for Integrative Human Physiology, Zurich (Switzerland)


    We aimed at assessing stent geometry and in-stent contrast attenuation with 64-slice CT in patients with various coronary stents. Twenty-nine patients (mean age 60 {+-} 11 years; 24 men) with 50 stents underwent CT within 2 weeks after stent placement. Mean in-stent luminal diameter and reference vessel diameter proximal and distal to the stent were assessed with CT, and compared to quantitative coronary angiography (QCA). Stent length was also compared to the manufacturer's values. Images were reconstructed using a medium-smooth (B30f) and sharp (B46f) kernel. All 50 stents could be visualized with CT. Mean in-stent luminal diameter was systematically underestimated with CT compared to QCA (1.60 {+-} 0.39 mm versus 2.49 {+-} 0.45 mm; P < 0.0001), resulting in a modest correlation of QCA versus CT (r = 0.49; P < 0.0001). Stent length as given by the manufacturer was 18.2 {+-} 6.2 mm, correlating well with CT (18.5 {+-} 5.7 mm; r = 0.95; P < 0.0001) and QCA (17.4 {+-} 5.6 mm; r = 0.87; P < 0.0001). Proximal and distal reference vessel diameters were similar with CT and QCA (P = 0.06 and P = 0.03). B46f kernel images showed higher image noise (P < 0.05) and lower in-stent CT attenuation values (P < 0.001) than images reconstructed with the B30f kernel. 64-slice CT allows measurement of coronary artery in-stent density, and significantly underestimates the true in-stent diameter compared to QCA. (orig.)

  7. Acute stent thrombosis after bifurcation stenting with the crush technique visualized with 64-slice computed tomography

    Kristensen, T.S.; Engstrom, T.; Kofoed, Klaus Fuglsang


    Acute stent thrombosis remains a potential complication after stent implantation. With the introduction of electrocardiographic gated multidetector row computed tomography (MDCT), a new nonnvasive imaging modality has become available that may contribute to the detection of complications after...

  8. Beam hardening artifacts by dental implants: Comparison of cone-beam and 64-slice computed tomography scanners

    Farzad Esmaeili


    Full Text Available Background: Cone beam computed tomography (CBCT is an alternative to a computed tomography (CT scan, which is appropriate for a wide range of craniomaxillofacial indications. The long-term use of metallic materials in dentistry means that artifacts caused by metallic restorations in the oral cavity should be taken into account when utilizing CBCT and CT scanners. The aim of this study was to quantitatively compare the beam hardening artifacts produced by dental implants between CBCT and a 64-Slice CT scanner. Materials and Methods: In this descriptive study , an implant drilling model similar to the human mandible was used in the present study. The implants (Dentis were placed in the canine, premolar and molar areas. Three series of scans were provided from the implant areas using Somatom Sensation 64-slice and NewTom VGi (CBCT CT scanners. Identical images were evaluated by three radiologists. The artifacts in each image were determined based on pre-determined criteria. Kruskal-Wallis test was used to compare mean values; Mann-Whitney U test was used for two-by-two comparisons when there was a statistical significance ( P < 0.05. Results: The images of the two scanners had similar resolutions in axial sections ( P = 0.299. In coronal sections, there were significant differences in the resolutions of the images produced by the two scanners ( P < 0.001, with a higher resolution in the images produced by NewTom VGi scanner. On the whole, there were significant differences between the resolutions of the images produced by the two CT scanners ( P < 0.001, with higher resolution in the images produced by NewTom VGi scanner in comparison to those of Somatom Sensation. Conclusion: Given the high quality of the images produced by NewTom VGi and the lower costs in comparison to CT, the use of the images of this scanner in dental procedures is recommended, especially in patients with extensive restorations, multiple prostheses and previous implants.

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

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


    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).

  10. Case series of 64 slice computed tomography-computed tomographic angiography with 3D reconstruction to diagnose symptomatic cerebral aneurysms: new standard of care?

    Dietrich Jehle


    Full Text Available CT angiography (CTA has improved significantly over the past few years such that the reconstructed images of the cerebral arteries may now be equivalent to conventional digital angiography. The new technology of 64 slice multi-detector CTA can reconstruct detailed images that can reliably identify small cerebral aneurysms, even those <3mm. In addition, it is estimated that CT followed by lumbar puncture (LP misses up to 4% of symptomatic aneurysms. We present a series of cases that illustrates how CT followed by CTA may be replacing CT-LP as the standard of care in working up patients for symptomatic cerebral aneurysms and the importance of performing three dimensional (3D reconstructions. A series of seven cases of symptomatic cerebral aneurysms were identified that illustrate the sensitivity of CT-CTA versus CT-LP and the importance of 3D reconstruction in identifying these aneurysms. Surgical treatment was recommended for 6 of the 7 patients with aneurysms and strict hypertension control was recommended for the seventh patient. Some of these patients demonstrated subarachnoid hemorrhage on presentation while others had negative LPs. A number of these patients with negative LPs were clearly symptomatic from their aneurysms. At least one of these cerebral aneurysms was not apparent on CTA without 3D reconstruction. 3D reconstruction of CTA is crucial to adequately identify cerebral aneurysms. This case series helps reinforce the importance of 3D reconstruction. There is some data to suggest that 64 slice CT-CTA may be equivalent or superior to CT-LP in the detection of symptomatic cerebral aneurysms.

  11. Diagnostic performance of prospectively ECG triggered versus retrospectively ECG gated 64-slice computed tomography coronary angiography in a heterogeneous patient population

    Lehmkuhl, Lukas, E-mail: [University of Leipzig - Heart Center, Department of Diagnostic and Interventional Radiology, Struempellstrasse 39, D-04289 Leipzig (Germany); Herz, Franziska; Foldyna, Borek [University of Leipzig - Heart Center, Department of Diagnostic and Interventional Radiology, Struempellstrasse 39, D-04289 Leipzig (Germany); Nagel, Hans Dieter [Dr. HD Nagel - Science and Technology for Radiology, Buchholz (Germany); Grothoff, Matthias; Nitzsche, Stefan [University of Leipzig - Heart Center, Department of Diagnostic and Interventional Radiology, Struempellstrasse 39, D-04289 Leipzig (Germany); Thiele, Holger [University of Leipzig - Heart Center, Department for Cardiology (Germany); Mohr, Friedrich-Wilhelm [University of Leipzig - Heart Center, Department for Cardiovascular Surgery (Germany); Hindricks, Gerhard [University of Leipzig - Heart Center, Department for Cardiology (Germany); Gutberlet, Matthias [University of Leipzig - Heart Center, Department of Diagnostic and Interventional Radiology, Struempellstrasse 39, D-04289 Leipzig (Germany)


    Objective: To compare diagnostic performance and applicability of prospectively versus retrospectively gated 64-slice computed tomography coronary angiography (pro-CTCA vs. retro-CTCA) in a heterogeneous patient population compared to invasive coronary angiography. Methods: 77 patients referred to an ECG-gated-CT of the chest were retrospectively included. Pro-CTCA was applied, whenever possible, alternatively retro-CTCA was performed. All coronary artery segments {>=}1.5 mm were analysed and image quality was assessed. Results: In 39 patients retro-CTCA and in 38 patients pro-CTCA was applied, mean heart rate (HR) was 69.5 {+-} 9.1 min{sup -1} and 62.8 {+-} 5.9, respectively. For a stenosis {>=}50% segment-based (patient-based) analysis revealed a sensitivity, specificity, positive (PPV) and negative predictive value (NPV) of 97%, 98%, 71%, 100% (91%, 82%, 67%, 96%) using retro-CTCA and 94%, 97%, 75%, 99% (93%, 96%, 93%, 96%) using pro-CTCA. Sensitivity and NPV increased in the pro-CTCA group in patients with a HR < 65. Vessel-based analysis showed lower diagnostic performance for the right coronary artery (RCA) using pro-CTCA, which increased when HR < 65. Image quality did not differ significantly in both groups. Conclusions: Prospectively triggered CTCA in a heterogeneous patient group has a very high diagnostic accuracy and image quality, when used in HR {<=} 65. A low HR is of special importance for the evaluation of the RCA.

  12. 64层锥束CT扫描的优化系统%Optimization of System Design for 64-slice Cone Beam Computed Tomography

    谢强; Eugene Williams; Charlie Shaughnessy; 唐向阳


    The technology for x-ray computed tomography (CT) has experienced tremendous growth in recent years. Since the introduction of 4-slice helical scanners in 1998, rapid improvement has been made on CT scanners in terms of the volume coverage, spatial resolution, scan speed, and the number of slices. These advancements not only significantly impact clinical applications, but also bring huge challenges to the CT system design. Because of the complexity of the volumetric CT (VCT) system, various strategies have to be utilized in the design process. These methodologies include theoretical analysis, computer simulation for system performance prediction, bench-top experiments for analysis confirmation, automated image analysis tools for automatically evaluating image performance, and double-blind tests with human observers for parameter optimization. In this paper, we present some of the system design considerations and optimization processes for a 64-slice scanner. These design processes ensure the optimal performance of the cone beam CT scanner. Initial clinical feedback has demonstrated the effectiveness of our approach.%近年来X射线断层成像(CT)技术获得了突飞猛进的发展,自1998年推出4层螺旋CT后,CT扫描设备在容积覆盖,空间分辨率,扫描速度,切片数方面取得了长足进展.这不仅给医学应用带来了深远的影响,同时也给CT系统设计提出了巨大的挑战.容积CT(VCT)的设计过程引入了各种策略来战胜其复杂性.这些方法学包括:理论分析,系统性能预测的图像分析工具,各种基于专家背对背评价的参数优化.本文论述了64层CT系统设计中的一些考虑因素及优化过程.这些设计过程保证了锥束CT的优化性能.首批客户的应用反馈显示了我们设计实践的有效率性.

  13. Multi-dimensional visualization of coronary aberrancies using multi detector computed tomography

    van Ooijen, P; Dorgelo, J; Tukker, W; Willemsen, H; Oudkerk, M; Lewis, BS; Halon, DA; Flugelman, MY; Gensini, GF


    The purpose of this study was to evaluate the usefulness of three and four dimensional visualization of multi detector computed tomography datasets for the evaluation of coronary aberrancies. Multi detector computed tomography (MDCT) datasets were obtained in thirteen patients following a standard p

  14. Combined use of 64-slice computed tomography angiography and gated myocardial perfusion SPECT for the detection of functionally relevant coronary artery stenoses. First results in a clinical setting concerning patients with stable angina

    Hacker, M.; Hack, N.; Tiling, R. [Klinikum Grosshadern (Germany). Dept. of Nuclear Medicine; Jakobs, T.; Nikolaou, K.; Becker, C. [Klinikum Grosshadern (Germany). Dept. of Clinical Radiology; Ziegler, F. von; Knez, A. [Klinikum Grosshadern (Germany). Dept. of Cardiology; Koenig, A.; Klauss, V. [Medizinische Poliklinik-Innenstadt, Univ. of Munich (Germany). Dept. of Cardiology


    Aim: In patients with stable angina pectoris both morphological and functional information about the coronary artery tree should be present before revascularization therapy is performed. High accuracy was shown for spiral computed tomography (MDCT) angiography acquired with a 64-slice CT scanner compared to invasive coronary angiography (ICA) in detecting ''obstructive'' coronary artery disease (CAD). Gated myocardial SPECT (MPI) is an established method for the noninvasive assessment of functional significance of coronary stenoses. Aim of the study was to evaluate the combination of 64-slice CT angiography plus MPI in comparison to ICA plus MPI in the detection of hemodynamically relevant coronary artery stenoses in a clinical setting. Patients, methods: 30 patients (63 {+-} 10.8 years, 23 men) with stable angina (21 with suspected, 9 with known CAD) were investigated. MPI, 64-slice CT angiography and ICA were performed, reversible and fixed perfusion defects were allocated to determining lesions separately for MDCT angiography and ICA. The combination of MDCT angiography plus MPI was compared to the results of ICA plus MPI. Results: Sensitivity, specificity, negative and positive predictive value for the combination of MDCT angiography plus MPI was 85%, 97%, 98% and 79%, respectively, on a vessel-based and 93%, 87%, 93% and 88%, respectively, on a patient-based level. 19 coronary arteries with stenoses =50% in both ICA and MDCT angiography showed no ischemia in MPI. Conclusion: The combination of 64-slice CT angiography and gated myocardial SPECT enabled a comprehensive non-invasive view of the anatomical and functional status of the coronary artery tree. (orig.)

  15. 64层螺旋CT三维重建活体肝静脉的研究及临床意义%3D-reconstruction of hepatic vein by 64-Slice Spiral Computed Tomography and its significance

    杨新文; 王剑华; 周庭永; 吕发金; 洪永华


    目的:探讨64层螺旋CT应用于正常人活体体肝静脉研究的可行性,观察三维重建肝静脉的一般形态及走行规律.方法:153例正常受试者经肘正中静脉注射造影剂后,使用64层螺旋CT进行上腹部扫描,图像采集后经容积再现(volume rendering,VR)技术重建肝静脉.结果:重建图像清晰,可显示出6~8级血管及与周围组织间的关系.其中153例肝静脉的分型结果如下:①3分支型,占35.3%(54例);②中左共干型,占41.8%(64例);③中左合干型,占20.9%(32例);④中右共干型,占2.0%(3例).结论:64层螺旋CT可以作为研究活体肝静脉形态的有效手段,三维重建能更准确、全方位地显示肝静脉的正常解剖类型和发现变异,而且图像清晰,对于活体肝静脉的研究有较好的临床应用价值.%Objective: To explore the feasibility of 64-Slice spiral computed tomography (CT) on reconstructing hepatic vein according to its morphology and distribution. Methods: After injecting contrast materials through median cubital vein, 153 voluneers underwent contrast-enhanced CT angiography of epigastric zone utilizing 64-Slice spiral computed tomography. Images were collected and dealt with the technique of volume rendering (VR),and then hepatic vein were reconstructed into 3D-images. Results: On reconstructed images, the vessels of the 6th and the 8th level, and their surrounding structures can be identified.According to the reconstruction images of 153 eases, hepatic.vein can be divided as follow types: ①Trifurcate type with the pencentage of 35.3% (54eases): left, middle and right hepatic veins drained into the inferior vena eava separately; ②Common trunk type of middle and left veins, 41.8% (64 cases): right hepatic vein drained into the inferior vena cava, however, left and middle hepatic veins confluened before their draining into the inferior vena cava; ③Common trunk type of left and right hepatic vein, 20.9% (32eases): left and middle

  16. Value of 64-slices spiral computed tomography in the diagnosis of cavernous transformation of portal vein%64层螺旋CT对门静脉海绵样变性的诊断价值

    李金平; 赵德利; 王彦民; 李大庆; 李艳英; 姜慧杰


    目的 探讨64层螺旋CT在门静脉海绵样变性(CTPV)诊断中的价值.方法 对CT检查发现的CTPV患者22例,采用MPR、MIP、VR等图像后处理技术显示异常的门静脉及侧支血管情况.结果 22例CTPV 在CT平扫上显示门静脉结构不清,肝门区可见多发的结节状、条状软组织影.增强扫描显示6例动脉期肝实质灌注异常;门静脉期11例患者门静脉主干和(或)左右分支增粗,内可见充盈缺损,4例门静脉显示不清;2例门静脉主干和(或)左右分支在正常范围内;4例门静脉主干变细;1例门静脉主干受侵致管腔狭窄.胆管周围静脉丛(86.36%)、胆囊静脉(77.27%)及食管胃底静脉(77.27%)呈点状、细网状、簇状扩张.结论 64层螺旋CT能准确显示CTPV的部位、范围,立体地显示各曲张血管的走行及曲张程度,是检查CTPV的有效手段.%Objective To investigate the value of 64-slice spiral computed tomography in the diagnosis of cavemous transformation of portal vein (CTPV). Methods A 64-slices spiral CT scanner was used to perform plain and three-phase contrast enhanced abdominal scanning in 22 patients with CTPV. Image post-processing techniques,including MPR,MIP and VR,were applied to depict the abnormal portal vein and its collateral vessels.Results The portal vein was not clearly seen on plain in 22 cases,while multiple soft tissue nodules and strips were found in the porta hepatis region. On dynamic enhanced scans,abnormal hepatic perfusion during arterial phase in 6 cases was demonstrated. On portal vein phase images the main trunk of portal vein and/or its left and right branches were dilated with filling defects in 11 cases. Inconspicuous portal veins were demonstrated. The main trunk of portal vein looked thin in 4 cases. The main trunk of portal vein was lumen stenosis as a result of tumor-infiltrating in 1 case. Pericholedochal venous plexus (86.36%) , cystic vein (77.27%)and esophageal gastric veins (77.27

  17. Quantitativa analysis by 64-slice computed tomography in diagnosis of intermediate coronary artery stenosis%64排CT冠状动脉造影定量分析在冠状动脉临界病变中的价值

    施鸿毓; 陈晖; 仇兴标; 曲新凯; 方唯一


    目的 评价64排CT冠状动脉造影对临界病变定量分析的可行性.方法 入选2009年5月-2010年8月于上海交通大学附属胸科医院行64排CT冠状动脉造影检查提示为临界病变的91例患者,共205处病变.在2周内进行经皮冠状动脉造影及定量冠状动脉造影(QCA)分析.采用Bland-Altman分析和Pearson相关分析对比64排CT冠状动脉造影定量分析与QCA的结果.结果 64排CT冠状动脉造影检查示,病变参考直径为(3.1±0.4) mm,病变长度为(14.2±11.3)mm;狭窄程度为(57.8±0.7)%,与QCA测定的(58.2±13.9)%的差异无统计学意义(P=0.64).205个经64排CT冠状动脉造影定量分析示冠状动脉狭窄程度为40%~70%的病变中,QCA检查示27个病变(13.2%)的狭窄程度低于40%,43个病变(21.0%)高于70%,135个病变(65.9%)属于冠状动脉狭窄程度为40%~70%的临界病变.64排CT冠状动脉造影定量分析与QCA结果呈中度相关(r=0.599,P<0.001),但一致性较差(平均偏差为0.4%,95%一致性可信区间为-22.1%~22.9%).结论 64排CT冠状动脉造影对临界病变的诊断价值有限,其定量分析与QCA的一致性欠佳,目前临床实用价值有限.%Objective To evaluate the feasibility of quantitative analysis by 64-slice computed tomography (CT) in intermediate coronary artery lesions. Methods Totally 91 patients with 205 lesions were diagnosed as intermediate coronary artery stenosis by 64-slice CT from May 2009 to August 2010. Conventional percutaneous coronary angiography was performed within 2 weeks after CT scan. The results of 64-slice CT quantitative analysis and quantitive coronary angiography (OCA) were compared by Bland-Altman analysis and Pearson correlations. Results The average reference values of lesions were (3.1 ±0.4) mm in diameter and (14.2±11.3) mm in length by CT scan. Diameter stenosis was (57.8 + 0.7)% by CT quantification and (58.2 + 13.91)% by OCAi there was no significant difference

  18. 64层螺旋CT血管成像在脊髓血管介入术前评估中的价值%Value of 64-slice spiral computed tomography angiography in preoperative evaluation of spinal vascular intervention

    肖云华; 吕富荣; 吕发金; 孙向前; 彭冈力


    目的 探讨64层螺旋CT在脊髓血管介入术前评估中的价值.方法 选择17例胸腰段脊髓损伤患者行脊柱64层螺旋CT增强扫描,重建薄层图像,层厚0.625 mm,间隔0.625 mm,以DICOM格式传输到ADW4.2工作站,采用容积显示(volume rendering,VR)、最大密度投影(maximum intensity projection,MIP)及多平面重建(multi-planar reformat,MPR)等后处理技术进行三维重建,分析脊髓供血动脉的走行特征.结果 17例患者中有16例患者(94%)胸腰段均可见根髓动脉供血脊髓,其中1支(6%)自T4/5左侧椎间孔进入椎管,2支(12%)自T10/11左侧椎间孔进入椎管,1支(6%)自T11/12左侧椎间孔进入椎管,4支(24%)根髓动脉自L1/2左侧椎间孔进入椎管,2支(12%)自L2/3左侧椎间孔进入椎管,2支(12%)自T11/12右侧椎间孔进入椎管,2支(12%)自T12/L1右侧椎间孔进入椎管,2支(12%)自L2/3右侧椎间孔进入椎管,10例(59%)患者根髓动脉自左侧椎间孔进入椎管.另有1例(6%)患者行CT和DSA检查均未发现根髓动脉.结论 64层螺旋CT能准确直观反映脊髓供血动脉的开口位置、走行方向、管径大小及其与周围血管的空间关系,为脊髓血管介入术前提供丰富的评估信息.%Objective To investigate the value of 64-slice spiral computed tomography(CT)angiography in preoperative evaluation of spinal vascular intervention.Methods Seventeen patients with segmental injury of the spinal cord underwent the enhanced 64-slice CT scan of the spine.Thin-slice reconstruction was done,with the slice thickness of 0.625 mm and interval of 0.625 mm.The data were transferred to the work station ADW4.2 in DICM format.Image postprocessing technologies such as volume rendering(VR),maximum intensity projection(MIP)and multi-planar reformat(MPR)were used to conduct three-dimensional reconstruction and analyze the anatomical characteristics of radiculomedullary artery.Results Radiculomedullary artery could be found in the thoracolumbar segment of

  19. Multi-detector computed tomography imaging of large airway pathology:A pictorial review

    Tejeshwar Singh Jugpal; Anju Garg; Gulshan Rai Sethi; Mradul Kumar Daga; Jyoti Kumar


    The tracheobronchial tree is a musculo-cartilagenous framework which acts as a conduit to aerate the lungs and consequently the entire body. A large spectrum of pathological conditions can involve the trachea and bronchial airways. These may be congenital anomalies, infections, post-intubation airway injuries, foreign body aspiration or neoplasms involving the airway. Appropriate management of airway disease requires an early and accurate diagnosis. In this pictorial essay review, we will comprehensively describe the various airway pathologies and their imaging findings by multi-detector computed tomography.

  20. Identification of Cardiac and Aortic Injuries in Trauma with Multi-detector Computed Tomography.

    Shergill, Arvind K; Maraj, Tishan; Barszczyk, Mark S; Cheung, Helen; Singh, Navneet; Zavodni, Anna E


    Blunt and penetrating cardiovascular (CV) injuries are associated with a high morbidity and mortality. Rapid detection of these injuries in trauma is critical for patient survival. The advent of multi-detector computed tomography (MDCT) has led to increased detection of CV injuries during rapid comprehensive scanning of stabilized major trauma patients. MDCT has the ability to acquire images with a higher temporal and spatial resolution, as well as the capability to create multiplanar reformats. This pictorial review illustrates several common and life-threatening traumatic CV injuries from a regional trauma center.

  1. Identification of Cardiac and Aortic Injuries in Trauma with Multi-detector Computed Tomography

    Arvind K Shergill


    Full Text Available Blunt and penetrating cardiovascular (CV injuries are associated with a high morbidity and mortality. Rapid detection of these injuries in trauma is critical for patient survival. The advent of multi-detector computed tomography (MDCT has led to increased detection of CV injuries during rapid comprehensive scanning of stabilized major trauma patients. MDCT has the ability to acquire images with a higher temporal and spatial resolution, as well as the capability to create multiplanar reformats. This pictorial review illustrates several common and life-threatening traumatic CV injuries from a regional trauma center.

  2. Evaluation of morphologic characteristics of the aortic root with 64-slice spiral computed tomography%64层螺旋CT对主动脉根部形态结构的评价

    陈华; 黄新苗; 赵仙先; 曹江; 秦永文


    目的 研究主动脉根部及临近组织结构64层螺旋CT(MSCT)成像技术、影像解剖及其临床意义.方法 60例无明显主动脉、主动脉瓣膜疾病患者行MSCT检查,采用多平面重建(MPR)、容积再现(VR)及仿真内镜(VE)等方法重建并测量相关数据.结果 测得主动脉根部直径(22.79±3.31)mm,主动脉窦间距(33.43±3.34)mm,冠脉开口处直径(30.06±2.70) mm,升主动脉内径(30.39±3.42),窦底平面至窦顶平面距离(19.18±2.21) mm.左右冠状动脉开口距主动脉根部距离分别为(15.71±3.53) mm、(15.96±3.78) mm.结论 应用MSCT增强扫描可清楚显示主动脉开口大小、冠脉开口位置、有无发育畸形及与周边结构关系,为带瓣膜支架的设计与经皮主动脉瓣膜植入手术顺利施行提供影像学依据.%Objective To explore the imaging technique for demonstrating the aortic root and its neighbouring structures with 64-slice spiral computed tomography, and to discuss the morphologic characteristics of the aortic root as well as their clinical signif'icance. Methods Multislice spiral CT scanning was performed in sixty adult patients who had no obvious ascending aorta diseases or aortic valve abnormalities. Multi-plane reconstruction (MPR) . volume rendering (VR)and virtual endoscopy (VE)were employed to demonstrate the anatomy of the aortic root, while the relevant data concerning the aorta and coronary smus were also determined. The results were analyzed. Results The mean aortic diameter at aortic root was(22.79 ± 3.3l)mm. the mean distance between coronary sinuses was (33.43 ± 3.34) mm, and the mean coronary diameter at its orifice was (30.06 ± 2.70) mm. The measurements also included the inner diameter of middle ascending aorta(30.39 ± 3.42) mm , the distance between the bottom plane and top plane of the coronary sinus(19.18 ± 2.21) mm, the distance between left coronary orifice and aortic root( 15.71 ± 3.53) mm and the distance between right coronary

  3. Multi-detector Computed Tomography Angiography of the Hepatic Artery in Liver Transplant Recipients

    Boraschi, P.; Donati, F.; Cossu, M.C.; Gigoni, R.; Vignali, C.; Filipponi, F.; Bartolozzi, C.; Falaschi, F. [Pisa Univ. Hospital (Italy). 2nd Dept. of Radiology


    PURPOSE: To evaluate the ability of multi-detector row computed tomography angiography (CTA) in detecting hepatic artery complications in the follow-up of liver transplant patients, performing volume-rendering as reconstruction technique. MATERIAL AND METHODS: The anatomy of hepatic artery was studied in 27 liver transplant recipients with a four-row CT scanner using the following parameters: collimation, 1 mm; slice width, 1 mm; table feed, 6-8 mm/s; spiral reconstruction time, 0.5 s; reconstruction interval, 0.5 mm; mAs, 160; kVp, 120. Before the study, the patients received 1000 ml of water as oral contrast agent to produce negative contrast in the stomach and the small bowel. A non-ionic contrast medium was infused intravenously at a rate of 5 ml/s with a bolus tracking system. Volume-rendering of hepatic artery was performed with the 3D Virtuoso software. RESULTS: The celiac trunk, the hepatic artery, and the right and left hepatic arteries were successfully displayed in high detail in all patients. Side branches, including small collaterals, and hepatic artery anastomosis could also be readily visualized. Volume-rendered CTA detected six hepatic artery stenoses, two hepatic artery thromboses, and two intrahepatic pseudoaneurysms. In two cases, CT detected hepatic artery stenosis with a diameter reduction of less than 50%, while digital subtraction angiography showed a normal artery. CONCLUSION: Volume-rendered multi-detector CTA is a promising non-invasive technique, since it allows images of high quality to be generated with excellent anatomical visualization of the hepatic artery and its complications in liver transplant recipients.

  4. Clinical application of 64-slice spiral computed tomography perfusion imaging technology in kidney disease%64层CT灌注成像技术在肾脏疾病中的应用价值

    唐烨真; 杜涛明; 唐光才; 兰永树; 涂永波; 林伟


    Objective: To investigate the clinical application value of 64-slice spiral CT perfusion imaging in kidney diseases diagnosis. Methods: Totally 40 patients met the case criteria, 64-slice spiral CT was used for renal perfusion scan. To observe the sharp of TDC, to records and count BF、BV、MTT and PS of every group. Results: To the same client, the perfusion parameters, index of BF, BV and PS averages and standard deviations of both sides of the kidney had no significant difference (P>0. 05). The BF, BV, MTT and PS among group of renal tumor, cirrhosis, hypertension and control had statistical differences ( P <0. 05). Conclusion: CTPI technologies can evaluate renal function in many aspects, with a promising application prospect.%目的:探讨64层CT灌注扫描技术在肾脏疾病诊断中的临床应用价值.方法:对40例符合入选标准的受检者行双肾灌注扫描,观察TDC形态,记录各组血流量(blood flow,BF)、血容量(blood volume,BV)、平均通过时间(mean transit time,MTT)、表面渗透性(permeability surface,PS)值,并进行统计学分析.结果:同一受检者两侧肾脏BF、BV和PS等参数差异无统计学意义(P>0.05).肾脏肿瘤、肝硬化、高血压及正常组各组间BF、BV及PS差异均有统计学意义(P<0.05).结论:CT灌注成像能从多方面对肾功能进行评价,具有良好的应用前景.

  5. Recurrence of Takotsubo Cardiomyopathy: Role of Multi- Detector Computed Tomography Coronary Angiography

    Yaser Jenab


    Full Text Available Takotsubo cardiomyopathy (TCM, also known as stress-induced cardiomyopathy, is a clinical syndrome of transient left ventricular (LV apical wall motion abnormality with relative preservation of the basal heart segments in the absence of any significant atherosclerosis. Recurrence of this condition is rare. We report a postmenopausal woman, who experienced two episodes of TCM within 4 months following emotional and physical stress. In the first episode, she was admitted due to severe dyspnea, accompanied by sudden-onset, prolonged, burning chest pain and palpitation. Transthoracic echocardiography revealed akinesia of the LV, with the exception of the basal regions. Coronary angiography demonstrated no significant coronary artery disease, and follow-up echocardiography showed normalization of the LV wall motion abnormalities. In the second episode, she experienced similar symptoms and echocardiography revealed similar changes. Multi-detector computed tomography revealed normal coronary arteries. After 9 days, she was discharged in good condition; and at 3 months’ follow- up, she was symptom-free with normal echocardiography.

  6. Reverse Redistribution in Myocardial Perfusion Imaging: Revisited with 64-slice MDCT

    Lee, Min Kyung; Kim, Jeong Ho; Hwang, Kyung Hoon; Choi, In Suck; Choi, Soo Jin; Choe, Won Sick [Gachon University Gil Hospital, Incheon (Korea, Republic of); Yoon, Min Ki [Good Samaritan Hospital, Pohang (Korea, Republic of)


    The authors report myocardial perfusion imaging of a patient showing reverse redistribution (RR) and a 64-slice multidetector-row computed tomography (MDCT) with corresponding findings. The patient had subendocardial myocardial infarction (MI) with positive electrocardiogram (EMG) findings and elevated levels of cardiac isoenzymes. Experiencing this case emphasizes the importance of complementary correlation of a new diagnostic modality that helps us to understand the nature of RR.

  7. Scoliotic Change in Patients Having Undergone a Mastectomy: Analysis Using Multi-Detector Computed Tomography

    Kim, Moo Sang; Kim, Hye Won; Juhng, Seon Kwan; Choi, Si Sung [Dept. of Radiology, Wankwang University School of Medicine, Iksan (Korea, Republic of)


    To evaluate the relationship between the degree of scoliotic curvature and postoperative change of the chest wall among patients who underwent a unilateral mastectomy. Subjects were comprised of 56 women who underwent chest CT and a whole spine standing anteroposterior view (WSSAP). Cobb's angle and each side of the chest wall volume, including the breast, were measured with the WSSAP and a 3-D reconstructed multi-detector computed tomography (MDCT) image. A correlation analysis was performed between the scoliotic curvature and chest wall volume asymmetry. Directional correspondence between development of scoliosis and undergoing a mastectomy was analyzed. Furthermore, a survey on patient shoulder function was performed using a questionnaire and a correlation was performed between the results of the survey and the scoliotic curvature and chest wall volume asymmetry. The findings indicate that Cobb's angles were 4.4 degree {+-} 2.7 (Mean {+-} SD, range from 0.6 to 11.4). Differences in chest wall volume were 474.64 {+-} 276.36 cm{sup 3} (Mean {+-} SD, range from 78 to 1379). No statistical significance was noted between the degree of scoliotic curvature and chest wall volume asymmetry (p > 0.05). A cross-tabulation analysis of the direction between the scoliotic curvature and mastectomy was found to be statistically significant (p < 0.001). Also, there was a significant correlation between shoulder function assessment score and the degree of scoliotic curvature (p = 0.003), while no significant correlation between shoulder function assessment score and chest wall volume asymmetry (p 0.091) could be found. Scoliotic change had a tendency to be on the opposite side of the mastectomy and had no statistically significant relationship with the volume asymmetry. Thus, 3-D reconstructed MDCT images are helpful in differentiating selective volume differences.

  8. Imaging features of solid pseudopapillary tumor of the pancreas on multi-detector row computed tomography

    Deng-Bin Wang; Qing-Bing Wang; Wei-Min Chai; Ke-Min Chen; Xia-Xing Deng


    AIM:To retrospectively analyze the imaging features of solid-pseudopapillary tumors (SPTs) of the pancreas on multi-detector row computed tomography (MDCT) and define the imaging findings suggestive of malignant potential.METHODS: A total of 24 consecutive cases with surgically and pathologically confirmed SPTs of the pancreas underwent preoperative abdominal MDCT studies in our hospital. All axial CT images, CT angiographic images, and coronally and sagittally reformed images were obtained. The images were retrospectively reviewed at interactive picture archiving and communication system workstations. RESULTS: Of the 24 cases of SPTs, 11 cases (45.8%) occurred in the pancreatic head and seven (29.1%) in the tail. Eighteen were pathologically diagnosed as benign and six as malignant. MDCT diagnosis of SPTs was well correlated with the surgical and pathological results (Kappa = 0.6, P < 0.05). The size of SPTs ranged from 3 to 15 cm (mean, 5.8 cm). When the size of the tumor was greater than 6 cm (including 6cm), the possibilities of vascular (8 vs 1) and capsular invasion (9 vs 0) increased significantly ( P < 0.05). Two pathologically benign cases with vascular invasion and disrupted capsule on MDCT presented with local recurrence and hepatic metastases during follow-up about 1 year after the resection of the primary tumors.CONCLUSION: Vascular and capsular invasion with superimposed spread into the adjacent pancreatic parenchyma and nearby structures in SPTs of the pancreas can be accurately revealed by MDCTpreoperatively. These imaging findings are predictive of the malignant potential associated with the aggressive behavior of the tumor, even in the pathologically benign cases.




    Full Text Available BACKGROUND : With the change in the pace of life fast , faster , fastest being the motto of the present day , the incidence of trauma and the associated mortality and morbidities is on a continuous rise.Imaging plays a very important role in the management of these injuries in deciding which injuries , in trauma the final verdict of organ injury in abdomen is intra - ope rative findings. AIMS : In view of the above said we considered to study to determine diagnostic accuracy of MDCT (Multi - Detector Computed Tomography in detection of intra - abdominal solid organ injury in blunt abdominal trauma and to highlight the importance of MDCT in evaluation of blunt abdominal trauma. METHODS AND MATERIALS : This was a prospective study done between over a period of 2 years from between January 2011 to February 2013 on patients who presented with blun t abdominal trauma after excluding patients who were managed conservatively and normal on imaging , the data we compared had 32 patients and the analysis was as follows. RESULTS : Blunt abdominal trauma was common in males , the male to female ratio was 9:1 , road traffic accident is the most common mode of injury in blunt abdominal trauma with 60% of the patients in this mode of injury , single organ injury is 22 patients (76% spleen is the most commonly injured organ 15(47% patients having splenic injury , wi th grade 3 being the commonest splenic injury 8 out of the 15 patients had splenic injury bowel injury was the second common organ injured in blunt trauma abdomen. In this study computed tomography grading correlated well with intra - operative grading with a PPV of= 95.45 % (95% ci: 84.50 % to 99.31 % Asensitivityof 76.36 % (95% ci: 62.98 % to 86.76 % . CONCLUSION : Computed tomography is an important imaging technique for diagnosis of organ injuries in patients with abdominal trauma. It helps in grading of the type of injury and accordingly deciding the management of patient. It is a highly

  10. Sixty-four-multi-detector computed tomography diagnosis of coronary artery anomalies in 66 patients

    YANG Shan; ZENG Meng-su; ZHANG Zhi-yong; LING Zhi-qing; MA Jian-ying; CHEN Gang


    Background The abnormalities of coronary arteries, though rare and sometimes benign, may first present clinically as myocardial infarction or sudden death. Multi-detector computed tomography (MDCT) is a non-invasive test that is highly suitable for detecting these anomalies. The study aimed to review the 64-MDCT appearance of the coronary artery anomalies in 66 patients and to discuss the clinical importance of these anomalies.Methods In 6014 consecutive patients examined over 12 months by 64-MDCT for the study of coronary artery disease, 66 were diagnosed for coronary artery anomalies. All patients were symptomatic for one or more of the following diseases: chest pain, dyspnoea, palpitations, arrhythmia and myocardial infarction. Nine patients had undergone a coronary angiography. All the CT images were evaluated by two radiologists and one cardiologist. The right coronary artery (RCA) and the conus branch arising separately, myocardial bridging and duplication of arteries were not analysed in our study.Results The incidence of coronary artery anomalies found in our study group was 1.097%. In the selected patients, seven different types of coronary anomalies were found by 64-MDCT examination. The high takeoff, origin of the coronary artery from the opposite or noncoronary sinus with an anomalous course, and coronary artery fistula were the three common forms of anomalies (n=16, 18 and 16, respectively). Compared with the results of the coronary angiography, the number of the drainage sites of two coronary artery fistula was less in MDCT images (3 small sites in total). In all cases, coronary artery computed tomography angiography (CTA) technique was able to recognize the origin of the coronary artery, its three-dimensional course and its spatial relationship with the adjacent structures. Conventional coronary angiography in two cases, however, was unable to provide sufficient information for correct and complete diagnosis.Conclusions In conclusion, the study

  11. Anatomical variation of thyroid veins on contrast-enhanced multi-detector row computed tomography

    Tomita, Hayato, E-mail: [Department of Radiology, St. Marianna University School of Medicine, Yokohama City Seibu Hospital, 1197-1 Yasashicho, Asahi-ku, Yokohama, Kanagawa 241-0811 (Japan); Yamada, Takayuki; Murakami, Kenji; Hashimoto, Kazuki; Tazawa, Yoko; Kumano, Reiko [Department of Radiology, St. Marianna University School of Medicine, Yokohama City Seibu Hospital, 1197-1 Yasashicho, Asahi-ku, Yokohama, Kanagawa 241-0811 (Japan); Nakajima, Yasuo [Department of Radiology, St. Marianna University School of Medicine, 2-16-1 Sugao, Miyamae-ku, Kawasaki, Kanagawa 216-8511 (Japan)


    Highlights: • This is the first study to demonstrate the anatomy of thyroid veins on contrasted-enhanced MDCT. • Identifying the thyroid vein on MDCT prior to selective venous sampling of parathyroid hormone provides clinical information to interventional radiologist. • Detecting especially the inferior thyroid veins with individual variability in numbers, locations, and lengths may have an effect on SVS for HPT and decrease the difficulty and time of the procedure. - Abstract: Objective: The objective of this study was to clarify the anatomical variation of thyroid veins into the systemic vein using contrast-enhanced multi-detector row computed tomography (MDCT). Design and methods: : The subjects were 80 patients (34 males and 46 females; mean age, 50.1 years; age range, 15–92 years) with neck diseases who underwent MDCT. The number and location of inflow points of the thyroid veins into the systemic vein, and the length from the junction of bilateral brachiocephalic veins to the orifice of inferior thyroid vein were investigated by reviewing the axial and coronal images. Results: All superior thyroid veins were detected. Right and left middle thyroid veins were identified in 39 and 29 patients, respectively. Right inferior thyroid veins, left inferior thyroid veins, and common trunks were detected in 43, 46, and 39 patients, respectively; in five patients, two left thyroid veins were identified. All left inferior thyroid veins and 34 common trunks flowed into the innominate vein, while right ones had some variations in inflow sites. Mean lengths were 3.01 ± 1.30 cm (range, 0.5–6.19) and 2.04 ± 0.91 cm (0.5–4.4) in the left inferior thyroid vein and common trunk, and 1.96 ± 1.05 cm (0.81–4.8) and 1.65 ± 0.69 cm (0.63–2.94) in the right one flowing into the right internal jugular vein and the innominate vein, respectively. Conclusions: The numbers and orifices of thyroid veins were identified at high rates on contrast-enhanced MDCT. This

  12. Intensive-care unit lung infections: The role of imaging with special emphasis on multi-detector row computed tomography

    Romano, Luigia; Pinto, Antonio; Merola, Stefanella; Gagliardi, Nicola; Tortora, Giovanni [Department of Diagnostic Imaging, Cardarelli Hospital, Naples Italy-Via G. Merliani 31, 80127 Naples (Italy); Scaglione, Mariano [Department of Diagnostic Imaging, Cardarelli Hospital, Naples Italy-Via G. Merliani 31, 80127 Naples (Italy)], E-mail:


    Nosocomial pneumonia is the most frequent hospital-acquired infection. In mechanically ventilated patients admitted to an intensive-care unit as many as 7-41% may develop pneumonia. The role of imaging is to identify the presence, location and extent of pulmonary infection and the presence of complications. However, the poor resolution of bedside plain film frequently limits the value of radiography as an accurate diagnostic tool. To date, multi-detector row computed tomography with its excellent contrast resolution is the most sensitive modality for evaluating lung parenchyma infections.

  13. A new approach to the assessment of lumen visibility of coronary artery stent at various heart rates using 64-slice MDCT

    Groen, J.M.; Greuter, M.J.W.; Ooijen, P.M.A. van; Oudkerk, M. [University Medical Center Groningen, University of Groningen, Department of Radiology, Hanzeplein 1, P.O. Box 30001, Groningen (Netherlands)


    Coronary artery stent lumen visibility was assessed as a function of cardiac movement and temporal resolution with an automated objective method using an anthropomorphic moving heart phantom. Nine different coronary stents filled with contrast fluid and surrounded by fat were scanned using 64-slice multi-detector computed tomography (MDCT) at 50-100 beats/min with the moving heart phantom. Image quality was assessed by measuring in-stent CT attenuation and by a dedicated tool in the longitudinal and axial plane. Images were scored by CT attenuation and lumen visibility and compared with theoretical scoring to analyse the effect of multi-segment reconstruction (MSR). An average increase in CT attenuation of 144 {+-} 59 HU and average diminished lumen visibility of 29 {+-} 12% was observed at higher heart rates in both planes. A negative correlation between image quality and heart rate was non-significant for the majority of measurements (P > 0.06). No improvement of image quality was observed in using MSR. In conclusion, in-stent CT attenuation increases and lumen visibility decreases at increasing heart rate. Results obtained with the automated tool show similar behaviour compared with attenuation measurements. Cardiac movement during data acquisition causes approximately twice as much blurring compared with the influence of temporal resolution on image quality. (orig.)

  14. Mapping epicardial fat with multi-detector computed tomography to facilitate percutaneous transepicardial arrhythmia ablation

    Abbara, Suhny [Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, MA (United States)]. E-mail:; Desai, Jay C. [Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, MA (United States); Cury, Ricardo C. [Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, MA (United States); Butler, Javed [Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, MA (United States); Nieman, Koen [Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, MA (United States); Reddy, Vivek [Division of Cardiology, Massachusetts General Hospital, Harvard Medical School, Boston, MA (United States)


    A sizable portion of ventricular tachycardia circuits are epicardial, especially in patients with non-ischemic cardiomyopathy, e.g. Chagas disease. Thus there is a growing interest among the electrophysiologists in transepicardial mapping and myocardial ablation for treatment of arrhythmias. However, increased epicardial fat can be a significant hindrance in procedural success as it can mimic infarct during mapping and can also decrease the effectiveness of ablation. Quantitative knowledge of epicardial fat pre-procedure can potentially significantly facilitate the conduct and outcomes of these procedures. In this study we assessed the epicardial fat distribution and thickness in vivo in 59 patients who underwent multi-detector computed tomography (MDCT) for coronary artery assessment using a 16-slice scanner. Multiplanar reconstructions were obtained in the ventricular short axis at the basal, mid ventricular, and near the apex level, and in a four-chamber view. In the short axis slices, we measured epicardial fat diameter in nine segments, and in the four-chamber view, it was measured in five segments. In grooved segments the maximum fat thickness was recorded, while in non-grooved segments thickness at three equally spaced points were averaged. The results were as follows starting clockwise: superior inter-ventricular (IV) groove (all measurements are in mm, in basal, mid ventricular, and apical levels, respectively) (11.2, 8.6, 7.3), left ventricular (LV) superior lateral wall (1.0, 1.5, 1.7), LV inferior lateral wall (1.3, 2.2, 3.5), inferior IV groove (9.2, 6.5, 6.1), right ventricular (RV) diaphragmatic wall (1.4, 0.2, 1.0), acute margin (9.2, 7.3, 7.8), RV anterior free wall inferior (6.8, 4.0, 4.7), RV anterior free wall superior (6.5, 3.2, 3.1), RV superior wall (5.6, 2.7, 4.0), We measured the following four-chamber segments: LV apex (2.8 mm), left atrio-ventricular (AV) groove (12.7), right AV groove (14.8), RV apex (4.8), and anterior IV groove (7

  15. Coronary ostial involvement in acute aortic dissection: detection with 64-slice cardiac CT.

    Ryan, E Ronan


    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.

  16. Optimal image reconstruction intervals for non-invasive coronary angiography with 64-slice CT

    Leschka, Sebastian; Husmann, Lars; Desbiolles, Lotus M.; Boehm, Thomas; Marincek, Borut; Alkadhi, Hatem [University Hospital Zurich, Institute of Diagnostic Radiology, Zurich (Switzerland); Gaemperli, Oliver; Schepis, Tiziano; Koepfli, Pascal [University Hospital Zurich, Cardiovascular Center, Zurich (Switzerland); Kaufmann, Philipp A. [University Hospital Zurich, Cardiovascular Center, Zurich (Switzerland); University of Zurich, Center for Integrative Human Physiology, Zurich (Switzerland)


    The reconstruction intervals providing best image quality for non-invasive coronary angiography with 64-slice computed tomography (CT) were evaluated. Contrast-enhanced, retrospectively electrocardiography (ECG)-gated 64-slice CT coronary angiography was performed in 80 patients (47 male, 33 female; mean age 62.1{+-}10.6 years). Thirteen data sets were reconstructed in 5% increments from 20 to 80% of the R-R interval. Depending on the average heart rate during scanning, patients were grouped as <65 bpm (n=49) and {>=}65 bpm (n=31). Two blinded and independent readers assessed the image quality of each coronary segment with a diameter {>=}1.5 mm using the following scores: 1, no motion artifacts; 2, minor artifacts; 3, moderate artifacts; 4, severe artifacts; and 5, not evaluative. The average heart rate was 63.3{+-}13.1 bpm (range 38-102). Acceptable image quality (scores 1-3) was achieved in 99.1% of all coronary segments (1,162/1,172; mean image quality score 1.55{+-}0.77) in the best reconstruction interval. Best image quality was found at 60% and 65% of the R-R interval for all patients and for each heart rate subgroup, whereas motion artifacts occurred significantly more often (P<0.01) at other reconstruction intervals. At heart rates <65 bpm, acceptable image quality was found in all coronary segments at 60%. At heart rates {>=}65 bpm, the whole coronary artery tree could be visualized with acceptable image quality in 87% (27/31) of the patients at 60%, while ten segments in four patients were rated as non-diagnostic (scores 4-5) at any reconstruction interval. In conclusion, 64-slice CT coronary angiography provides best overall image quality in mid-diastole. At heart rates <65 bpm, diagnostic image quality of all coronary segments can be obtained at a single reconstruction interval of 60%. (orig.)

  17. Diagnostic value of 64-slice spiral computed tomography chest angiography triple examination in acute chest pain%64排螺旋CT血管成像胸部三联检查对急性胸痛的诊断价值

    齐晨晖; 范红燕; 史琼玉


    Objective To explore the clinical value of triple examination with 64-slice spiral CT chest angiography(CTA) in diagnosis of acute chest pain. Methods 80 patients with acute chest pain as study group underwent CTA. The examinations of coronary artery,pulmonary artery and aorta were done one time under ECG-gated. 50 patients received only 64-slice computed tomography coronary angiography, pulmonary angiography and aortic angiography as control group. The image quality of CTA in two groups was evaluated. Results The image quality of control group was better than that of study group, but there was of significant statistical difference between study group and the control group (χ =324. 4,P = 0. 00). There were no statistical difference between two groups and intragroup about the image quality of aorta, pulmonary artery including ascending aorta,aortic arch,descending aorta and the central pulmonary artery, peripheral pulmonary artery (P>0. 05) , the image quality of two groups was as the same as batter. Conclusion 64-slice spiral CT chest angiography triple examination can display aorta, pulmonary artery and coronary artery with good image quality, it has a important clinical value in differential diagnosis of the cause of acute chest pain.%目的 探讨64排螺旋CT血管成像(computed tomography angiography,CTA)胸部三联检查在急性胸痛诊断中的临床应用价值.方法 收集本院以急性胸痛为首发症状者80例为研究组,行64排螺旋CT胸部动脉成像,在心电门控下一次性完成主动脉、肺动脉及冠状动脉扫描;选择单纯行冠状动脉、肺动脉及主动脉CTA扫描者各50例为对照组,评价胸部CTA三联检查成像质量.结果 冠状动脉成像质量研究组与对照组比较有显著统计学差异(χ2=324.4,P=0.00),对照组优于研究组.主动脉和肺动脉成像质量在升主动脉、主动脉弓、降主动脉及中央肺动、外周肺动脉2组整体和组间比均无统计学差异(P>0.05),2

  18. Impact of 64-slice coronary CT on the management of patients presenting with acute chest pain: results of a prospective two-centre study

    Christiaens, Luc [Departement d' imagerie Cardiovasculaire, Assistance Publique- Hopitaux de Paris, Hopital Lariboisiere, Paris (France); CHU de Poitiers, Departement de Cardiologie, Poitiers (France); Duchat, Florent; Boudiaf, Mourad; Fargeaudou, Yann; Ledref, Olivier; Soyer, Philippe [Departement d' imagerie Cardiovasculaire, Assistance Publique- Hopitaux de Paris, Hopital Lariboisiere, Paris (France); Tasu, Jean-Pierre [CHU de Poitiers, Departement de Radiologie, Poitiers (France); Sirol, Marc [Departement d' imagerie Cardiovasculaire, Assistance Publique- Hopitaux de Paris, Hopital Lariboisiere, Paris (France); INSERM UFR U942, Insuffisance Cardiaque et Biomarqueurs, Universite Paris 7 - Denis Diderot, Hopital Lariboisiere, Paris (France); Universite Paris VII - Denis Diderot, Assistance Publique - Hopitaux de Paris, Service de Radiologie Vasculaire, Hopital Lariboisiere, Paris (France)


    Our two-centre prospective study evaluates the usefulness of 64-slice coronary computed tomography (CCT) to rule out significant coronary artery stenosis in patients admitted in emergency departments (ED) for acute coronary syndromes (ACS) with low-to-intermediate risk score. Patients (175) admitted for acute chest pain (ACP), unmodified electrocardiogram and first troponin measurement within normal ranges were included. A second troponin measurement and a 64-slice CCT within 24 h were performed. Major adverse cardiac events (MACE) were recorded during follow-up (6 months {+-} 2). 64-slice CCT was either normal or showed non-significant coronary stenosis in the majority of patients (78%). 64-slice CCT depicted significant stenosis (>50% diameter) in 22% of patient whereas initial clinical and biological evaluation was reassuring. For negative CCTs, elevated troponin at second measurement did not modify the strategy or treatment of patients. No MACEs were noted during follow up. In 12% of patients CCT identified unsuspected non-coronary abnormalities. Our study confirms 64-slice CCT utility to rule out significant coronary artery stenosis in 8/10 patients admitted in ED with ACP or ACS with low-to-intermediate risk score. Early discharge with a negative 64-slice CCT is associated with very low risk of cardiac events at 6 months. (orig.)

  19. 64-slice coronary computed tomography angiography using low tube voltage of 80 kV in subjects with normal body mass indices: comparative study using 120 kV

    Jun, Bo Ram; Yong, Hwan Seok; Kang, Eun-Young; Woo, Ok Hee; Choi, Eun Jung [Department of Radiology, Korea University Guro Hospital, Korea University College of Medicine, Seoul (Korea, Republic of)], E-mail:


    Background. The radiation dose of coronary computed tomography (CT) angiography (CCTA) is generally higher than that of CT scans of other parts of the body, and there is concern that the high radiation dose may result in increased cancer risk. Although various techniques have recently been introduced to lower the radiation dose of CCTA, there has been no direct comparison between protocols with 80 and 120 kV. Purpose. To assess the image quality and radiation dose of 80-kV electrocardiography (ECG)-gated CCTA in subjects with a normal body mass index (BMI), compared to 120-kV ECG-gated CCTA. Material and Methods. This retrospective study was approved by our local ethics board, and the requirement of written informed consent was waived. We analyzed the CCTA images of 100 subjects with BMIs <25 kg/m2. Fifty subjects underwent 120-kV CCTA, and the other 50 subjects underwent 80-kV CCTA. Two blinded observers independently evaluated the subjective image quality of the coronary arteries. The objective image quality (signal-to-noise ratio [SNR] and contrast-to-noise ratio [CNR]) and radiation dose were also measured in each group. Results. Although the objective image quality of the 80-kV protocol images was significantly poorer than that of 120-kV protocol images (mean SNR, 14.9 {+-} 4.7 vs. 19.8 {+-} 4.4, P < 0.0001; mean CNR, 15.2 {+-} 4.8 vs. 21.6 {+-} 4.7, P < 0.0001), there was no significant difference in the subjective image quality between the two groups (mean image score, 4.7 {+-} 1.1 vs. 4.5 {+-} 0.7 for radiologist 1, P 0.273; 5.0 {+-} 1.0 vs. 4.8 {+-} 1.0 for radiologist 2, P = 0.197). The radiation dose was reduced by 70% with the 80-kV protocol and by 88% with the 80-kV and ECG-based tube current modulation than with the 120-kV protocol (3.42 {+-} 1.16 and 2.9 {+-} 0.8 vs. 11.49 {+-} 3.62 mSv, P < 0.0001). Conclusion. The low tube voltage CCTA protocol using 80 kV allows significant reduction of the radiation dose without impairing the subjective image

  20. Elective vs non-elective radial artery grafts: comparing midterm results through 64-Slice computed tomography Enxertos de artéria radial eletivos vs emergência: comparando resultados em seguimento a médio prazo

    Roberto Rocha-e-Silva


    Full Text Available BACKGROUND: Left internal thoracic artery to left anterior descending artery (LITA-LADA grafting has become a fundamental part of the coronary artery bypass graft procedure (CABG. This grafting in turn has led to an increased use of other arterial conduits, of which the radial artery (RA is most popular. Whether RA grafting can be used in the emergency patient is controversial. METHODS: 47 patients with critical stenosis (>70% in all target vessels underwent CABG with LITA and RA grafts from 1996 to 2003. Patients were divided into elective (23 patients and non-elective groups (24 patients with LITA and RA grafts per patient being similar in both groups. Of these 47 patients, 5 died from non-cardiac complications and 12 were unavailable. Thus, 30 patients (71% of survivors were studied by multidetector computed tomography. A total of 36 LITA and 64 RA grafts were studied. RESULTS: The RA patency rate for elective and non-elective grafts were 82% (31/38 and 85% (22/26, respectively (p=0.75. The RA had a similar patency rate for all target vessels ranging from 73% to 100%. Only one patient had a redo CABG and 29 (97% are free from angina or re-intervention. LITA-LADA had a 92% (11/12 and 100% (10/10 patency rate for elective and non-elective groups, respectively (p=0.37. The sequential LITA-diagonal-LADA in the elective group had a 50% (03/06 patency rate, which was significantly lower than the 100% (08/08 patency rate of the non-elective group (p=0.02. CONCLUSION: Radial Artery grafts can be used in both elective and non-elective patients with excellent results.INTRODUÇÃO: A anastomose da artéria torácica interna esquerda com a artéria descendente anterior (ATIE-DA se tornou parte fundamental da cirurgia de revascularização do miocárdio (RM. Esta técnica levou ao aumento de utilização de outros enxertos arteriais, entre os quais, a artéria radial (AR é muito usasa. Na literatura há controvérsia se a AR pode ser usada em pacientes

  1. Diagnostic accuracy of non-invasive 64-slice CT coronary angiography in patients with stable angina pectoris

    Pugliese, Francesca; Krestin, Gabriel P. [Erasmus Medical Center, Department of Radiology, Rotterdam (Netherlands); Mollet, Nico R.A.; deFeyter, Pim J. [Erasmus Medical Center, Department of Radiology, Rotterdam (Netherlands); Erasmus Medical Center, Department of Cardiology, Rotterdam (Netherlands); Runza, Giuseppe [University of Palermo, Department of Radiology, Palermo (Italy); Azienda Ospedaliera di Parma, Department of Radiology, Parma (Italy); Mieghem, Carlos van; Meijboom, Willem B.; Baks, Timo [Erasmus Medical Center, Department of Cardiology, Rotterdam (Netherlands); Malagutti, Patrizia [Erasmus Medical Center, Department of Cardiology, Rotterdam (Netherlands); University of Ferrara, Department of Cardiology, Ferrara (Italy); Cademartiri, Filippo [Erasmus Medical Center, Department of Radiology, Rotterdam (Netherlands); Azienda Ospedaliera di Parma, Department of Radiology, Parma (Italy)


    Multislice computed tomography (CT) is an emerging technique for the non-invasive detection of coronary stenoses. While the diagnostic accuracy of 4-slice scanners was limited, 16-slice CT imagers showed promising results due to increased temporal and spatial resolution. These technical advances prompted us to evaluate the diagnostic performance of 64-slice CT coronary angiography in the detection of significant stenoses (defined as {>=} 50% luminal diameter reduction) versus invasive quantitative coronary angiography (QCA). Thirty-five patients with stable angina pectoris underwent CT coronary angiography performed with a 64-slice scanner (gantry rotation time 330 ms, individual detector width 0.6 mm) prior to conventional coronary angiography. Patients with heart rates >70 beats/min received 100 mg metoprolol orally. One hundred millilitres of contrast agent with an iodine concentration of 400 mgl/ml were injected at a rate of 5 ml/s into the antecubital vein. The CT scan was triggered with the bolus tracking technique. The sensitivity, specificity and the positive and negative predictive values of 64-slice CT were 99%, 96%, 78% and 99%, respectively, on a per-segment basis. The values obtained on a per-patient basis were 100%, 90%, 96% and 100%, respectively. When referral to catheterisation is questionable, CT coronary angiography may identify subjects with normal angiograms and consistently decrease the number of unnecessary invasive procedures. (orig.)

  2. Discordant findings of dimercaptosuccinic acid scintigraphy in children with multi-detector row computed tomography-proven acute pyelonephritis

    Jeongmin Lee


    Full Text Available Purpose : The diagnosis of acute pyelonephritis (APN is often difficult, as its clinical and biological manifestations are non-specific in children. If not treated quickly and adequately, however, APN may cause irreversible renal damage, possibly leading to hypertension and chronic renal failure. We were suspecting the diagnostic value of 99mTc-dimercaptosuccinic acid (DMSA scan by experiences and so compared the results of DMSA scan to those of multi-detector row computed tomography (MDCT. Methods : We retrospectively selected and analyzed 81 patients who were diagnosed as APN by MDCT during evaluation of their acute abdomen in emergency room and then received DMSA scan also for the diagnostic work-up of APN after admission. We evaluated the results of imaging studies and compared the diagnostic value of each method by age groups, &lt;2 years (n=45 and ?#242; years (n=36. Results : Among total 81 patients with MDCT-proven APN, DMSA scan was diagnostic only in 55 children (68%, while the remaining 26 children (32% showed false negative normal findings. These 26 patients were predominantly male and most of them, 19 (73.1% were &lt;2 years of age. Conclusion : DMSA scan holds obvious limitation compared to MDCT in depicting acute inflammatory lesions of kidney in children with APN, especially in early childhood less than 2 years of age. MDCT showed hidden lesions of APN, those were undetectable through DMSA scan in children.

  3. Acute gastrointestinal bleeding: detection of source and etiology with multi-detector-row CT

    Scheffel, Hans; Pfammatter, Thomas; Marincek, Borut; Alkadhi, Hatem [University Hospital Zurich, Institute of Diagnostic Radiology, Zurich (Switzerland); Wildi, Stefan [University Hospital Zurich, Department of Visceral and Transplant Surgery, Zurich (Switzerland); Bauerfeind, Peter [University Hospital Zurich, Division of Gastroenterology, Zurich (Switzerland)


    This study was conducted to determine the ability of multi-detector-row computed tomography (CT) to identify the source and etiology of acute gastrointestinal bleeding. Eighteen patients with acute upper (n = 10) and lower (n = 8) gastrointestinal bleeding underwent 4-detector-row CT (n = 6), 16-detector-row CT (n = 11), and 64-slice CT (n = 1) with an arterial and portal venous phase of contrast enhancement. Unenhanced scans were performed in nine patients. CT scans were reviewed to determine conspicuity of bleeding source, underlying etiology, and for potential causes of false-negative prospective interpretations. Bleeding sources were prospectively identified with CT in 15 (83%) patients, and three (17%) bleeding sources were visualized in retrospect, allowing the characterization of all sources of bleeding with CT. Contrast extravasation was demonstrated with CT in all 11 patients with severe bleeding, but only in 1 of 7 patients with mild bleeding. The etiology could not be identified on unenhanced CT scans in any patient, whereas arterial-phase and portal venous-phase CT depicted etiology in 15 (83%) patients. Underlying etiology was correctly identified in all eight patients with mild GI bleeding. Multi-detector-row CT enables the identification of bleeding source and precise etiology in patients with acute gastrointestinal bleeding. (orig.)

  4. Acute gastrointestinal bleeding: detection of source and etiology with multi-detector-row CT.

    Scheffel, Hans; Pfammatter, Thomas; Wildi, Stefan; Bauerfeind, Peter; Marincek, Borut; Alkadhi, Hatem


    This study was conducted to determine the ability of multi-detector-row computed tomography (CT) to identify the source and etiology of acute gastrointestinal bleeding. Eighteen patients with acute upper (n = 10) and lower (n = 8) gastrointestinal bleeding underwent 4-detector-row CT (n = 6), 16-detector-row CT (n = 11), and 64-slice CT (n = 1) with an arterial and portal venous phase of contrast enhancement. Unenhanced scans were performed in nine patients. CT scans were reviewed to determine conspicuity of bleeding source, underlying etiology, and for potential causes of false-negative prospective interpretations. Bleeding sources were prospectively identified with CT in 15 (83%) patients, and three (17%) bleeding sources were visualized in retrospect, allowing the characterization of all sources of bleeding with CT. Contrast extravasation was demonstrated with CT in all 11 patients with severe bleeding, but only in 1 of 7 patients with mild bleeding. The etiology could not be identified on unenhanced CT scans in any patient, whereas arterial-phase and portal venous-phase CT depicted etiology in 15 (83%) patients. Underlying etiology was correctly identified in all eight patients with mild GI bleeding. Multi-detector-row CT enables the identification of bleeding source and precise etiology in patients with acute gastrointestinal bleeding.

  5. Measurement of response of pulmonal tumors in 64-slice MDCT

    Sohns, Christian; Sossalla, Samuel (Dept. of Cardiology and Pneumology/Heart Center, Georg-August-Univ., Goettingen (Germany)), e-mail:; Mangelsdorf, Johanna; Obenauer, Silvia (Dept. of Radiology, Georg-August-Univ., Goettingen (Germany)); Konietschke, Frank (Dept. of Medical Statistics, Georg-August-Univ., Goettingen (Germany))


    Background: Advances in CT technology from single to multi-detector row CT (MDCT) permit a high resolution and volumetric presentation of pulmonary lesions. This implicates emerging measurement techniques that need to be contrasted with established methods. Purpose: To compare bidimensional, unidimensional, and volumetric methods for evaluation of treatment response in patients with lung lesions. Material and Methods: This study comprised 68 patients with pulmonary lesions who underwent a total of 276 64-MDCTs of chest at baseline and follow-up. RECIST and WHO criteria were used for unidimensional and bidimensional methods and region growing (RG) for volumetry. Patients were classified into four response categories. Respectively, two measurement techniques were contrasted and the kappa index was calculated. For intra-observer reproducibility the relative measurement error (RME) and kappa index with regard to agreement of response categories were evaluated. Results: Comparison of WHO und RECIST criteria achieves high correlation with kappa indices of 0.76 and 0.82. In particular, lesions with moderate increase of size in the range of 25-44% for bidimensional and 12-29% for unidimensional measurement result in different response categories when applying WHO and RECIST criteria. WHO criteria delivered PD more often than RECIST. kappa indices of 0.79 and 0.87 were attained in comparison of RECIST and RG, and 0.83 and 0.84 for WHO and RG. RME was 2.82% for RECIST, 7.53% for WHO, and 8.97% for RG. Intra-observer reproducibility was 95% for RECIST, 95% for WHO, and 96% for RG. Conclusion: The comparison of all methods resulted in no statistically significant differences. WHO criteria seemed to diverge the most, they declared several lesions prematurely as progression, and showed no benefit in comparison to RECIST. RG showed the best reproducibility, considered irregular lesions, was slightly superior to RECIST, and could be applied uniformly. Unidimensional measurement

  6. Criteria for establishing shielding of multi-detector computed tomography (MDCT) rooms.

    Verdun, F R; Aroua, A; Baechler, S; Schmidt, S; Trueb, P R; Bochud, F O


    The aim of this work is to compare two methods used for determining the proper shielding of computed tomography (CT) rooms while considering recent technological advances in CT scanners. The approaches of the German Institute for Standardisation and the US National Council on Radiation Protection and Measurements were compared and a series of radiation measurements were performed in several CT rooms at the Lausanne University Hospital. The following three-step procedure is proposed for assuring sufficient shielding of rooms hosting new CT units with spiral mode acquisition and various X-ray beam collimation widths: (1) calculate the ambient equivalent dose for a representative average weekly dose length product at the position where shielding is required; (2) from the maximum permissible weekly dose at the location of interest, calculate the transmission factor F that must be taken to ensure proper shielding and (3) convert the transmission factor into a thickness of lead shielding. A similar approach could be adopted to use when designing shielding for fluoroscopy rooms, where the basic quantity would be the dose area product instead of the load of current (milliampere-minute).

  7. Diagnostic performance of using effervescent powder for detection and grading of esophageal varices by multi-detector computed tomography

    Cansu, Aysegul, E-mail: [Department of Radiology, Karadeniz Technical University School of Medicine, Farabi Hospital, 61080 Trabzon (Turkey); Ahmetoglu, Ali; Kul, Sibel; Yukunc, Gokcen [Department of Radiology, Karadeniz Technical University School of Medicine, Farabi Hospital, 61080 Trabzon (Turkey); Fidan, Sami; Arslan, Mehmet [Department of Gastroenterology, Karadeniz Technical University School of Medicine, Farabi Hospital, 61080 Trabzon (Turkey); Topbas, Murat [Department of Public Health, Karadeniz Technical University School of Medicine, Farabi Hospital, 61080 Trabzon (Turkey)


    Purpose: To investigate the effect of using effervescent powder (EP) on the efficacy of multi-detector computed tomography (MDCT) in detection and grading of esophageal varices in cirrhotic patients by considering endoscopy as the gold standard. Materials and methods: Ninety-two cirrhotic patients undergoing biphasic liver MDCT followed by upper gastrointestinal endoscopy within 4 weeks of MDCT were prospectively evaluated. The patients were divided into two groups before MDCT. The first group (n = 50) received effervescent powder (EP) before and during MDCT procedure and the second group did not receive (n = 42). The presence, size and grade of the esophageal varices were evaluated. MDCT findings were compared with endoscopic results. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and accuracy of MDCT with EP and without EP were calculated and compared. Correlations between the grades of the varices for each group based on MDCT imaging and endoscopic grading were also evaluated. Results: The sensitivity, specificity, accuracy, PPV, and NPV of MDCT were 100%, 88%, 96%, 94%, and 100%, respectively, in the EP group, whereas they were 76%, 67%, 74%, 89%, and 43%, respectively, in the non-EP group. Correlations between the grades of the esophageal varices on MDCT and endoscopy were significant in both groups (r = 0.94, p < 0.001 for EP group and r = 0.70, p < 0.001 for non-EP group). Conclusion: During periodic CT scanning of cirrhotic patients, use of EP increases the success rate of MDCT for detection and grading of esophageal varices.

  8. Predictive value of multi-detector computed tomography for accurate diagnosis of serous cystadenoma: Radiologic-pathologic correlation

    Anjuli A Shah; Nisha I Sainani; Avinash Kambadakone Ramesh; Zarine K Shah; Vikram Deshpande; Peter F Hahn; Dushyant V Sahani


    AIM:To identify multi-detector computed tomography (MDCT) features mos t predi c t i ve of serous cystadenomas (SCAs),correlating with histopathology,and to study the impact of cyst size and MDCT technique on reader performance.METHODS:The MDCT scans of 164 patients with surgically verified pancreatic cystic lesions were reviewed by two readers to study the predictive value of various morphological features for establishing a diagnosis of SCAs.Accuracy in lesion characterization and reader confidence were correlated with lesion size (≤3 cm or ≥3 cm) and scanning protocols (dedicated vs routine).RESULTS:28/164 cysts (mean size,39 mm;range,8-92 mm) were diagnosed as SCA on pathology.The MDCT features predictive of diagnosis of SCA were microcystic appearance (22/28,78.6%),surface lobulations (25/28,89.3%) and central scar (9/28,32.4%).Stepwise logistic regression analysis showed that only microcystic appearance was significant for CT diagnosis of SCA (P=0.0001).The sensitivity,specificity and PPV of central scar and of combined microcystic appearance and lobulations were 32.4%/100%/100% and 68%/100%/100%,respectively.The reader confidence was higher for lesions>3 cm (P=0.02) and for MDCT scans performed using thin collimation (1.25-2.5 mm) compared to routine 5 mm collimation exams (P>0.05).CONCLUSION:Central scar on MDCT is diagnostic of SCA but is seen in only one third of SCAs.Microcystic morphology is the most significant CT feature in diagnosis of SCA.A combination of microcystic appearance and surface lobulations offers accuracy comparable to central scar with higher sensitivity.

  9. Imaging features of intraductal papillary mucinous neoplasms of the pancreas in multi-detector row computed tomography

    Ling Tan; Ya-E Zhao; Deng-Bin Wang; Qing-Bing Wang; Jing Hu; Ke-Min Chen; Xia-Xing Deng


    AIM:To retrospectively evaluate the imaging features of pancreatic intraductal papillary mucinous neoplasms (IPMNs) in multi-detector row computed tomography (MDCT).METHODS:A total of 20 patients with pathologicallyconfirmed intraductal papillary mucinous neoplasms (IPMNs) were included in this study.Axial MDCT images combined with CT angiography (CTA) and multiplanar volume reformations (MPVR) or curved reformations (CR) were preoperatively acquired.Two radiologists (Tan L and Wang DB) reviewed all the images in consensus using an interactive picture archiving and communication system.The disputes in readings were resolved through consultation with a third experienced radiologist (Chen KM).Finally,the findings and diagnoses were compared with the pathologic results.RESULTS:The pathological study revealed 12 malignant IPMNs and eight benign IPMNs.The diameters of the cystic lesions and main pancreatic ducts (MPDs) were significantly larger in malignant IPMNs compared with those of the benign IPMNs (P<0.05).The combinedtype IPMNs had a higher rate of malignancy than the other two types of IPMNs (P<0.05).Tumors with mural nodules and thick septa had a significantly higher incidence of malignancy than tumors without these features (P<0.05).Communication of side-branch IPMNs with the MPD was present in nine cases at pathologic examination.Seven of them were identified from CTA and MPVR or CR images.From comparison with the pathological diagnosis,the sensitivity,specificity,and accuracy of MDCT in characterizing the malignancy of IPMN of the pancreas were determined to be 100%,87.5% and 95%,respectively.CONCLUSION:MDCT with CTA and MPVR or CR techniques can elucidate the imaging features of IPMNs and help predict the malignancy of these tumors.

  10. 64排螺旋CT检测冠状动脉病变与同型半胱氨酸水平的相关性研究%Correlation between 64-slice spiral computed tomography coronary angiography and homocystein in coronary artery disease

    刘丽; 贺延; 王松涛; 吕俊刚


    目的 探讨64排螺旋CT(MSCT)检测冠状动脉病变与同型半胱氨酸水平的相关性.方法 入选研究对象87例,均未接受叶酸和(或)维生素B12等治疗,分为急性冠状动脉综合征(ACS)组33例、稳定型心绞痛(SAP)组29例和正常对照组25例,均行冠状动脉MSCT成像检查,根据CT值进一步将ACS和SAP患者分为易损斑块组26例,混合斑块组19例,钙化斑块组17例;对所有研究对象检测血清同型半胱氨酸(Hcy)浓度.结果 3组间血清Hcy浓度按ACS组(16.44±5.48) μmol/L、SAP组(13.06±5.80) μmol/L、正常对照组(9.94±4.23) μmol/L顺序递减(均P<0.01);易损斑块组和混合斑块组血清Hcy浓度均高于钙化斑块组,为(16.50±5.24) μmol/L、(15.51±6.24) μmol/L vs(11.63±5.21) μmol/L(均P<0.01);ACS组与SAP组斑块构成比不同(x2=7.628,P<0.05);ACS组易损斑块检出率(42.4%)高于SAP组(17.2%),ACS组钙化斑块检出率(18.2%)低于SAP组(48.3%)(均P<0.05);斑块的不同性质与血清Hcy浓度间存在相关关系(rs=0.467,P<0.01).结论 冠状动脉MSCT联合血清Hcy化验检查可作为诊断冠心病并预测其严重程度的无创方法在临床上得以应用.%Objective To explore the correlation between 64-slice spiral computed tomography ( MSCT) coronary angiography and homocystein( Hey) in coronary artery disease. Methods Eighty-seven patients were divided into three groups:coronary artery syndrome (ACS) group 33 cases, stable angina pectoris(SAP) group 29 cases and healthy control group 25 cases. No one had received drug therapy with folic acid and/or vitamin B12. All patients underwent 64-slice spiral computed tomography angiography to distinguish the different quality of coronary plaques. According to the CT scale, all coronary artery disease patients were divided into vulnerable plaque group, mix plaque group and hard plaque group. Blood samples were taken to measure Hey level in all patients. Results Mean Hey level of ACS

  11. Comparison of aortic annulus diameter measurement between multi-detector computed tomography and echocardiography: a meta-analysis.

    Ruifang Zhang

    Full Text Available BACKGROUND AND PURPOSE: Accurate measurement of aortic annulus diameter is crucial for choosing suitable prosthetic size for transcatheter aortic valve implantation (TAVI. Several imaging methods are available for the measurement, but significant variability between different modalities has been observed. The purpose of this study was to systematically compare the measurements of aortic annulus diameter between multi-detector computed tomography (MDCT, transthoracic echocardiography (TTE, and transesophegeal echocardiography (TEE. METHODS: PubMed and EMBASE databases between January 2000 and January 2012 were searched. We extracted data from eligible studies evaluating the aortic annulus diameter by MDCT and echocardiography (TTE, TEE, or both. We performed a random-effects meta-analysis to calculate the weighted mean differences of aortic annulus diameter measurement between MDCT, TTE, and TEE. RESULTS: A total of 10 eligible studies involving 581 subjects with aortic valve stenosis were included. Aortic annulus diameter measured on coronal view by MDCT (25.3±0.52 mm was respectively larger than that measured on sagittal view by MDCT (22.7±0.37 mm, TTE (22.6±0.28 mm, and TEE (23.1±0.32 mm. The weighted mean difference of aortic annulus diameter between coronal view by MDCT and TTE these two methods was 2.97 mm, followed by the weighted mean difference of 2.53 mm between coronal view and sagittal view by MDCT, and the mean difference of 1.74 mm between coronal view on MDCT and TEE (P<0.0001 for all. The weighted mean difference of aortic annulus diameter measurement between TEE and TTE was significant but somewhat small (0.45 mm, P = 0.007. CONCLUSION: Aortic annulus diameter measured on coronal view by MDCT was robustly and significantly larger than that obtained on sagittal view by MDCT, TTE, or TEE. Such variability of aortic annulus diameter measurement by different imaging modalities cannot be ignored when developing optimal

  12. Clinical investigation of coronary artery calcification detected by 64-slice spiral computed tomography in diagnosis of coronary heart disease%64层螺旋CT量化冠状动脉钙化在冠心病中的诊断价值

    苏瑞瑛; 肖文良; 申艳霞; 田帅


    目的 探讨64层螺旋CT(64-slice spiral computed tomography,64SCT)量化冠状动脉钙化(coronary artery calcification,CAC)对诊断冠心病(coronary heart disease,CHD)的价值.方法 对56例临床诊断及可疑冠心病患者,进行64SCT冠脉成像及其钙化的量化分析,并同期进行选择性经皮冠状动脉造影(coronary angiography,CAG)检查,CAG采用经典插管法,冠状动脉钙化积分(coronary artery calcification score,CACS)采用Agatston方法完成,64SCT结果与CAG结果做双盲对照研究;根据CAG结果将患者分为冠心病组34例(冠状动脉至少有1支血管狭窄≥50%)和非冠心病组22例;进一步将224支血管按狭窄程度分为A组(狭窄<50%)、B组(狭窄50%~75%)和C组(狭窄>75%),记录其CACS分别进行统计分析;按照年龄分为<60岁组和≥60岁组,分别分析CAC率和CACS与年龄的关系.结果 64SCT冠状动脉三维成像对冠状动脉钙化显示清晰,对冠状动脉各分支显示良好,冠心病组的CACS与非冠心病组比较,差异有统计学意义(P<0.01),且A组与B、C组比较CACS差异有统计学意义(P<0.01),但B组、C组两组之间CACS差异无统计学意义(P>0.05);随着年龄的增长,CAC率和CACS逐渐增高,<60岁组与≥60岁组CAC率和CACS比较差异有统计学意义(P<0.01);<60岁组冠心病患者CAC率和CACS明显高于非冠心病组(P<0.05),≥60岁组冠心病患者CAC率与非冠心病组比较差异无统计学意义(P>0.05),但CACS差异有统计学意义(P<0.01).结论 应用64SCT量化冠状动脉钙化,可以对可疑冠心病患者提供早期诊断依据,CACS与相应血管管腔狭窄的对照分析显示,CACS与冠状动脉狭窄程度之间有一定关系;年龄对CAC有影响.

  13. Application of 64 slice spiral CT in evaluating the patency of coronary artery after stent implantation

    Yong-Shu Gao; Xing-Can Ma


    Objective:To explore the feasibility and effectiveness of 64 slice spiral CT in evaluating the patency of coronary artery after stent implantation.Methods:The 64 slice spiral CT image data of 125 patients after coronary artery stent implantation were collected, meanwhile, the image data of 25 patients underwent coronary angiography were also collected. The feasibility and accuracy of 64 slice spiral CT coronary artery stent imaging were comparatively analyzed. Results: The 64 slice spiral CT imaging quality with a stent diameter greater than 3.00 mm was significantly superior to that with a diameter of 2.25-3.00 mm. The CT imaging quality in the left main coronary artery and anterior descending artery was significantly higher than that in the left circumflex coronary artery. The CT imaging quality in the left main coronary artery was significantly higher than that in the right coronary artery. The CT reconstruction imaging quality in the drug coating stent was significantly superior to that in the bare metal stent. The sensitivity of 64 slice spiral CT was 100.00%, and the accuracy was 100.00%. In detecting the coronary artery with occlusion and stenosis (stent stenosis greater than 50%), the sensitivity was 90.00%, the false negative rate was 10.00%, and the positive predicative value was 100.00%.Conclusions:The effect of 64 slice spiral CT coronary imaging in evaluating the patency of coronary artery after stent implantation is highly consistent with that by coronary angiography, with a simple operation, less risk, and low cost, and thus, it can be completely taken as the imaging method in evaluating the patency of coronary artery after stent implantation.

  14. Endovascular treatment of thoracic aortic diseases: Follow-up and complications with multi-detector computed tomography angiography

    Iezzi, Roberto [Department of Radiology, University ' G. D' Annunzio' , Chieti (Italy)], E-mail:; Cotroneo, Antonio Raffaele; Marano, Riccardo; Filippone, Antonella; Storto, Maria Luigia [Department of Radiology, University ' G. D' Annunzio' , Chieti (Italy)


    Endovascular procedures with placement of stent-graft has become an accepted alternative to traditional open surgery for treatment of descending thoracic aortic aneurysms, ulcers, post-traumatic rupture, or complications of type-B dissection, due to significant reduction in perioperative mortality, rate of complications and length of hospitalization. Moreover, increasing operator experience and continuous advances in stent-graft technology are making treatment of a wider range of cases possible with redefinition of guidelines for endovascular stent-graft. The feasibility of endovascular stent-graft is mainly dependent on anatomic factors which represent the important predictors of the success of this procedure as well as on strictly follow-up in order to obtain early detection and treatment of eventual complications. Multi-detector CT-angiography is a fast, safe, and minimally invasive imaging technique that represents the standard of reference in the follow-up of patients who have undergone endovascular stent-graft, as it is effective and specific in the detection of procedure-correlated complications. The purpose of this article is to give a brief review of those techniques most commonly used for endovascular treatment of thoracic aortic diseases together with a more detailed description of post-procedural complications and their appearance on multi-detector CT-angiography.

  15. Evaluation of temporal windows for coronary artery bypass graft imaging with 64-slice CT

    Desbiolles, Lotus; Leschka, Sebastian; Scheffel, Hans; Husmann, Lars; Garzoli, Elisabeth; Marincek, Borut; Alkadhi, Hatem [University Hospital Zurich, Institute of Diagnostic Radiology, Zurich (Switzerland); Plass, Andre [University Hospital Zurich, Clinic for Cardiovascular Surgery, Zurich (Switzerland); Gaemperli, Oliver [University Hospital Zurich, Cardiovascular Center, Zurich (Switzerland); Kaufmann, Philipp A. [University Hospital Zurich, Cardiovascular Center, Zurich (Switzerland); University of Zurich, Center for Integrative Human Physiology, Zurich (Switzerland)


    Temporal windows providing the best image quality of different segments and types of coronary artery bypass grafts (CABGs) with 64-slice computed tomography (CT) were evaluated in an experimental set-up. Sixty-four-slice CT with a rotation time of 330 ms was performed in 25 patients (four female; mean age 59.9 years). A total of 84 CABGs (62 individual and 22 sequential grafts) were evaluated, including 28 internal mammary artery (33.3%), one radial artery with sequential grafting (2.4%), and 54 saphenous vein grafts (64.3%). Ten data sets were reconstructed in 10% increments of the RR-interval. Each graft was separated into segments (proximal and distal anastomosis, and body), and CABG types were grouped according to target arteries. Two readers independently assessed image quality of each CABG segment in each temporal window. Diagnostic image quality was found with good inter-observer agreement (kappa=0.62) in 98.5% (202/205) of all graft segments. Image quality was significantly better for saphenous vein grafts versus arterial grafts (P<0.001) and for distal anastomosis to the right coronary compared with other target coronary arteries (P<0.05). Overall, best image quality was found at 60%. Image quality of proximal segments did not significantly vary with the temporal window, whereas for all other segments image quality was significantly better at 60% compared with other temporal windows (P<0.05). Sixty-four-slice CT provides best image quality of various segments and types of CABG at 60% of the RR-interval. (orig.)

  16. Angiotomografía computada multicorte 64 en patología de la arteria aorta The 64 multi detector row computed tomography in aortic patology diagnostic

    Diego Haberman


    Full Text Available La angiotomografía computada representa una metodología diagnóstica de gran utilidad que ha cobrado mayor importancia con los nuevos avances tecnológicos. La tomografía computada multicorte con 64 hileras de detectores nos brinda la posibilidad de estudiar con gran precisión y enorme detalle estructuras cada vez más pequeñas, ofreciendo una nueva perspectiva en el diagnóstico de la patología aórtica.The angio computed tomography represents a great utility diagnostic method that has reached greater importance with its technological new developments. The 64 multi detector row computed tomography allows the evaluation with great precision and detail of very small structures, offering a new perspective in aortic patology diagnostic.

  17. Visualisation of passive middle ear implants by cone beam and multi-detector computed tomography: a comparative in vitro study

    Nguyen, T.D.; Koesling, S. [University of Halle-Wittenberg, Department of Radiology, Halle Saale (Germany); Mlynski, R. [Head and Neck Surgery ' ' Otto Koerner' ' , Department of Otorhinolaryngology, Rostock (Germany); Plontke, S.K. [University of Halle-Wittenberg, Department of Otorhinolaryngology, Head and Neck Surgery, Halle Saale (Germany)


    Modern passive middle ear titanium prostheses are filigree structures, resulting in poorer depiction on CT compared to prostheses used in the past. We compared the visibility of newer prostheses on cone beam CT (CBCT) to multi-detector CT (MDCT) with standard and lower dose in vitro, and analysed image noise and metal artefacts. Six different titanium middle ear prostheses (three partial and one total ossicular replacement prostheses, two stapes prostheses) were implanted twice in formalin-fixed head specimens - first correctly and then with displacement. Imaging was performed using standard CBCT and MDCT as well as MDCT with lower dose (36 single imaging investigations). Images were analysed with knowledge of the used types of middle ear prostheses, but blinded with respect to the positioning in the specific case. On all images the type of prostheses and their positions could be clearly recognized. Their identifiability including their details was rated as statistically significantly higher for all CBCT investigations than for MDCT. MDCT with lower dose showed the worst results. No statistical differences were found in image noise and metal artefacts. If available, CBCT should be preferred over MDCT in diagnostic evaluation of passive middle ear prostheses. (orig.)

  18. Adolescent Kawasaki disease: usefulness of 64-slice CT coronary angiography for follow-up investigation

    Carbone, Iacopo; Cannata, David; Algeri, Emanuela; Galea, Nicola; Napoli, Alessandro; Catalano, Carlo; Passariello, Roberto; Francone, Marco [Sapienza University of Rome, Department of Radiological, Onchological and Anatomopathological Sciences, Policlinico Umberto I, Rome (Italy); De Zorzi, Andrea [Bambino Gesu Hospital, Cardiology Division, Rome (Italy); Bosco, Giovanna; D' Agostino, Rita [Sapienza University of Rome, Unit of Paediatric Cardiology, Policlinico Umberto I, Rome (Italy); Menezes, Leon [University College of London, Institute of Nuclear Medicine, London (United Kingdom)


    Kawasaki disease (KD) is a systemic vasculitis that mainly affects coronary arteries in children, and requires regular follow-up from the time of diagnosis. To evaluate the feasibility of 64-slice CT angiography (CTA) for follow-up of patients with KD using previously performed invasive catheter coronary angiography (CCA) as reference standard. The study group comprised 12 patients (age 17.6 {+-} 2.9 years, mean{+-}SD) with a diagnosis of KD and a previously performed CCA (interval, 32.6 {+-} 13.5 months) who underwent 64-slice cardiac CTA. The quality of the images for establishing the presence of coronary abnormalities was determined by two observers. The CTA findings were compared with those from the prior CCA. Adequate image quality was obtained in all patients. Mean effective dose for CTA was 6.56 {+-} 0.95 mSv. CTA allowed accurate identification, characterization and measurement of all coronary aneurysms (n = 32), stenoses (n = 3) and occlusions (n = 9) previously demonstrated by CCA. One patient with disease progression went on to have percutaneous coronary intervention. Coronary lesions were reliably evaluated by 64-slice CTA in the follow-up of compliant patients with KD, reducing the need for repeated diagnostic invasive CCA. Hence, in an adequately selected patient population, the role of CCA could be limited almost only to therapeutic procedures. (orig.)

  19. The evaluation of the cardiac and small airway changes in pectus excavatum of children with 64-slice computed tomography%64层螺旋CT对儿童漏斗胸的心脏及小气道改变的评价

    赵磊磊; 何玲; 陈欣; 陈建蓉; 刘代松


    Objective:Through the retrospective research of cardiac rotation and small airway changes in pectus excavatum, we investigate the effect of the degree of sternal depression on them and the value of the 64-slice CT. Methods: 64-slice CT and three-dimensional reconstruction features of pectus excavatum proved clinically 183 cases between 2009 and 2011 were retrospectively reviewed. Measured the Haller index,cardiac rotation angle on axial CT images of the chest,researched the small airway changes on MPR lung-window. Haller index was used as standard to classify the cases to three grades,analysed differences between the three grades on cardiac angle,small airway changes,and investigated the effect of the degree of sternal depression on them. Results:183 cases were classified into three grades: mid-grade: 54 cases(2. 86 + 0. 31) , middle-grade: 22cases(3. 36 + 0. 10) ,high-grade: 107case(4. 61 ± 1. 27). The three grades were significant different(P<0. 05). The cardiac rotation angle of the three grades were 55. 52° ± 8. 76°,57. 38° ± 5. 03°,65. 93° ± 7. 67°,there were significant difference among them (P<0. 05). 60 cases had small airway changes,the morbidity of the three grades were 22. 22%(12/54) ,22. 73%(5/22) ,40. 19%(43/107), there were significant difference among the three grades(P<0. 05). 53 cases among them had lobus pulrnonis sinister small airway changes. Conclusion:The 64-slice CT is a better tool for revealing chest deformity,cardiac rotation and small airway changes of pectus excavatum. As the degree of chest deformity increase, the cardiac rotation angle, morbidities of small airway changes increases,the three exist positive correclation.%目的:通过CT观察儿童漏斗胸心脏形态及小气道改变,探讨胸廓畸形程度对心脏形态、小气道改变的影响及64层螺旋CT的价值.方法:搜集2009~2011年临床确诊漏斗胸并行胸部64层螺旋CT三维重建检查的患儿183例,测量胸廓的Haller指数、心脏旋转

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

    Haraldsdottir, Sigurdis, E-mail: [Boston Medical Center, 72 East Concord Street (Evans 124), Boston, MA, 02118 (United States); Gudnason, Thorarinn, E-mail: [Landspitali University Hospital, Hringbraut, 101 Reykjavik (Iceland); Sigurdsson, Axel F., E-mail: [Landspitali University Hospital, Hringbraut, 101 Reykjavik (Iceland); Gudjonsdottir, Jonina, E-mail: [Rontgen Domus Medica, Egilsgata 3, 101 Reykjavik (Iceland); Lehman, Sam J., E-mail: [Massachusetts General Hospital, 165 Cambridge Street, Suite 400, Boston, MA 02114 (United States); Eyjolfsson, Kristjan, E-mail: [Landspitali University Hospital, Hringbraut, 101 Reykjavik (Iceland); Scheving, Sigurpall S., E-mail: [Landspitali University Hospital, Hringbraut, 101 Reykjavik (Iceland); Gibson, C. Michael, E-mail: [Beth Israel Deaconess Medical Center, 330 Brookline Avenue, Boston, MA 02115 (United States); Hoffmann, Udo, E-mail: [Massachusetts General Hospital, 165 Cambridge Street, Suite 400, Boston, MA 02114 (United States); Jonsdottir, Birna, E-mail: [Rontgen Domus Medica, Egilsgata 3, 101 Reykjavik (Iceland); Andersen, Karl, E-mail: [Landspitali University Hospital, Hringbraut, 101 Reykjavik (Iceland)


    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.

  1. Comparative evaluation of 64-slice CT angiography and digital subtraction angiography in assessing the cervicocranial vasculature

    Randolf Klingebiel


    Full Text Available Randolf Klingebiel1, Max Kentenich3, Hans-Christian Bauknecht3, Florian Masuhr2, Eberhard Siebert1, Markus Busch2, Georg Bohner11Department of Neuroradiology, 2Department of Neurology, 3Department of Radiology, Charité Universitary Medicine Berlin, GermanyBackground: Noninvasive 64-slice computed tomography angiography (64-MSCTA closely approximates conventional catheter angiography (DSA in terms of detail resolution. Objective: Retrospective evaluation of cervicocranial (cc 64-MSCTA in comparison with DSA in patients with presumptive cc vascular disorders.Material and methods: Twenty-four 64-MSCTA studies (32 mm detector width, slice thickness 0.5 mm, 120 kv, 150 mAs, pitch 0.75 of patients with presumptive cc vascular pathology (13 men, 11 women, mean age 38.3 ± 11.3 yrs, range 19–54 yrs were assessed in comparison with DSA studies without abnormal findings in age-matched patients (11 men, 13 women, mean age 39.7 ± 11.9 yrs, range 18–54 yrs. Study readings were performed in a blinded manner by two neuroradiologists with respect to image quality and assessibility of various cc vascular segments by using a five-point scale. Radiation exposure was calculated for 64-MSCTA.Results: Each reader assessed 384/528 different vessel segments (64-MSCTA/DSA. Superior image quality was attributed to DSA with respect to the C1 ICA–C6 ICA, A3 ACA, and P3 PCA segments as well the AICA and SCA. 64-MSCTA was scored superior for C7 ICA and V4 VA segments. A significantly increased number of nonassessable V2- and V3 VA segments in DSA studies was noted. The effective dose for 64-MSCTA amounted to 2.2 mSv.Conclusions: 64-MSCTA provides near-equivalent diagnostic information of the cc vasculature as compared with DSA. According to our results, DSA should be considered primarily when peripheral vessels (A3/P3 or ICA segments close to the skull base (C2-5 are of interest, such as in primary angiitis or stenoocclusive ICA disease, respectively.Keywords: CT

  2. Clinical application of 64-slice spiral CT in the diagnosis of the Tetralogy of Fallot

    Wang Ximing [Tianjin Medical University, Tianjin City (China) and Shandong Medical Imaging Research Institute, Jinan City, Shandong Province 250021 (China)], E-mail:; Wu Lebin [Shandong Medical Imaging Research Institute, Jinan City, Shandong Province 250021 (China); Sun Cong [Shandong Medical Imaging Research Institute, Jinan City, Shandong Province 250021 (China); Shandong University Medical College, Shandong Jinan 250012 (China); Liu Cheng [Shandong Medical Imaging Research Institute, Jinan City, Shandong Province 250021 (China); Chao, Bao-Ting [Shandong University Medical College, Shandong Jinan 250012 (China); Han Bo [Shandong Provincial Hospital Pediatric Department, Shandong, Jinan 250021 (China); Zhang Yunting [Tianjin Medical University, General Hospital MR Department, Tianjin City (China); Chen Haisong [Shandong Medical Imaging Research Institute, Jinan City, Shandong Province 250021 (China); Shandong University Medical College, Shandong Jinan 250012 (China); Li Zhenjia [Shandong Medical Imaging Research Institute, Jinan City, Shandong Province 250021 (China)


    Objective: To explore the clinical application of 64-slice spiral CT in the diagnosis of the Tetralogy of Fallot. Methods: Eighteen patients with diagnosed Tetralogy of Fallot underwent cardiac CT angiography with 64-slice CT (CTA). Two- and three-dimensional images were used for diagnosing in all cases by means of MPR (coronal, sagital and oblique), cMPR, MIP and VRT. Results: All patients had ventricular septal defect, pulmonary stenosis and hypertrophy of right ventricle. The morphologic features of Tetralogy of Fallot were equal to echocardiography. Patent ductus arteriosus (PDA) were detected on eight patients. Main coronary artery branches and partial sub-branches were visualized in all patients. Abnormal coronary arteries were found in seven cases: both left and right main coronary artery arising from the right aortic sinus one case, right main coronary artery and circumflex (CX) arising from the right aortic sinus one case, left anterior descending (LAD) and CX arising from left aortic sinus directly one case, left and right coronary artery arising from back and front of the aortic sinus, respectively, three cases. Pulmonary artery branch stenosis was found in 12 cases and branch pulmonary artery dilation noticed in 1 case. Double superior vena cava was also found in one case. According to the surgery the diagnostic accuracy of CT and Echocardiography was 95.45 and 83.33%, respectively. Conclusion: Two- and three-dimensional 64-slice CTA not only show the overall anatomical structure of the heart, but also show coronary and pulmonary arteries. With these results, evaluation of coronary anomalies and pulmonary artery stenosis with 64-MSCT is extremely valuable for planning the operative procedure on the patients with Tetralogy of Fallot.

  3. Cardiac CT angiography after coronary artery surgery in children using 64-slice CT scan

    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:


    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.

  4. Diagnostic value of 64-slice spiral CT angiography in the diagnosis of multiple intracranial aneurysms: a report of 25 cases

    Hong-sheng WANG


    Full Text Available Objective  To evaluate the diagnostic value of 64-slice spiral CT angiography (CTA in multiple intracranial aneurysms (MIA. Methods  Twenty-five patients (9 males and 16 females, aged from 17 to 68 years with suspected MIA underwent 64-slice spiral CTA with slice thickness of 0.625mm. The data of all patients were reconstructed with multiplanar reconstruction (MPR, 3-dimensional shade surface display (3-SSD, volume rendering (VR and maximum intensity projection (MIP. The clinical diagnostic value was evaluated with the results of surgery or interventional embolization therapy. Results  A total of 61 aneurysms were detected by 64-slice spiral CTA in 25 patients, among them 17 patients were with 2 aneurysms, 6 patients with 3 aneurysms, 1 patient with 4 aneurysms and 1 patient with 5 aneurysms. The 64-slice spiral CTA could not only clearly demonstrate MIA, but also the size, neck, axis point and parent artery of each aneurysm, and the spatial relationship between aneurysm and the adjacent vessels and bone structures. Twenty-one patients underwent microsurgery and four underwent embolization, the location, size and shape of aneurysm and its spatial relationship with adjacent structures were in accordance with the findings of 64-slice spiral CTA. Conclusion  The 64-slice spiral CTA could be used as the first choice in the diagnosis of MIA for its high accuracy, and may be an important adjunct to digital subtraction angiography (DSA in MIA treatment.

  5. Multi-detector computed tomography is equivalent to trans-oesophageal echocardiography for the assessment of the aortic annulus before transcatheter aortic valve implantation

    Rixe, Johannes; Schmitt, Joern; Neumann, Thomas; Hamm, Christian W.; Rolf, Andreas [Kerckhoff Heart and Thorax Center, Department of Cardiology, Bad Nauheim (Germany); University Hospital of Giessen and Marburg, Site Giessen, Department of Internal Medicine I (Cardiology, Angiology), Giessen (Germany); Schuhbaeck, Annika; Nef, Holger M.; Achenbach, Stephan [University Hospital of Giessen and Marburg, Site Giessen, Department of Internal Medicine I (Cardiology, Angiology), Giessen (Germany); Liebetrau, Christoph; Moellmann, Helge; Szardien, Sebastian; Brandt, Roland [Kerckhoff Heart and Thorax Center, Department of Cardiology, Bad Nauheim (Germany); Schneider, Christian; Krombach, Gabriele [University Hospital of Giessen and Marburg, Department of Radiology, Giessen (Germany)


    In transcatheter aortic valve implantation (TAVI), assessment of the aortic annulus is mandatory. We sought to investigate the correlation between trans-oesophageal echocardiography (TEE) and multi-detector computed tomography (MDCT) for annulus diameter assessment before TAVI. A total of 122 patients (67 male, mean age 84 {+-} 6 years) underwent MDCT and TEE for TAVI planning. In TEE annulus diameters were obtained in a long-axis view at diastole. MDCT data were evaluated using MPR images, and corresponding projections were adjusted for MDCT and TEE. Patients were classified by the predominant localisation of aortic valve calcifications, and annulus diameters between TEE and MDCT were correlated. Additionally, the eccentricity of the aortic annulus was calculated. Mean eccentricity of the aortic annulus determined by MDCT was 0.34 {+-} 0.17, with no difference according to valve calcification. Regarding the aortic annulus diameter, the mean values measured were 24.3 {+-} 2.1 mm in MDCT and 24.0 {+-} 2.5 mm in TEE (P < 0.0001 for agreement). Independent of the pattern of aortic valve calcification, close correlation is found between CT and TEE measurements of the aortic annulus diameter. In addition, CT demonstrates the non-circular shape of the aortic annulus. (orig.)

  6. Correctness of multi-detector-row computed tomography for diagnosing mechanical prosthetic heart valve disorders using operative findings as a gold standard

    Tsai, I.Chen [Taichung Veterans General Hospital, Department of Radiology, Taichung (China); Institute of Clinical Medicine and Faculty of Medicine, National Yang-Ming University, Taipei (China); Lin, Yung-Kai; Chang, Yen; Wang, Chung-Chi; Hsieh, Shih-Rong; Wei, Hao-Ji; Tsai, Hung-Wen [Taichung Veterans General Hospital, Section of Cardiovascular Surgery, Cardiovascular Center, Taichung (China); Fu, Yun-Ching; Jan, Sheng-Ling [Institute of Clinical Medicine and Faculty of Medicine, National Yang-Ming University, Taipei (China); Taichung Veterans General Hospital, Section of Pediatric Cardiology, Department of Pediatrics, Taichung (China); Wang, Kuo-Yang [Taichung Veterans General Hospital, Section of General Cardiology, Cardiovascular Center, Taichung (China); Chung-Shan Medical University, Department of Medicine, Taichung (China); Chen, Min-Chi; Chen, Clayton Chi-Chang [Taichung Veterans General Hospital, Department of Radiology, Taichung (China); Central Taiwan University of Science and Technology, Department of Radiological Technology, Taichung (China)


    The purpose was to compare the findings of multi-detector computed tomography (MDCT) in prosthetic valve disorders using the operative findings as a gold standard. In a 3-year period, we prospectively enrolled 25 patients with 31 prosthetic heart valves. MDCT and transthoracic echocardiography (TTE) were done to evaluate pannus formation, prosthetic valve dysfunction, suture loosening (paravalvular leak) and pseudoaneurysm formation. Patients indicated for surgery received an operation within 1 week. The MDCT findings were compared with the operative findings. One patient with a Bjoerk-Shiley valve could not be evaluated by MDCT due to a severe beam-hardening artifact; thus, the exclusion rate for MDCT was 3.2% (1/31). Prosthetic valve disorders were suspected in 12 patients by either MDCT or TTE. Six patients received an operation that included three redo aortic valve replacements, two redo mitral replacements and one Amplatzer ductal occluder occlusion of a mitral paravalvular leak. The concordance of MDCT for diagnosing and localizing prosthetic valve disorders and the surgical findings was 100%. Except for images impaired by severe beam-hardening artifacts, MDCT provides excellent delineation of prosthetic valve disorders. (orig.)

  7. Comparison of MDCTA (16-slice multi-detector row computed tomography arthrography) and MRA (magnetic resonance arthrography) for detecting labral lesions of the shoulder

    Choi, Seung A; Cha, Jang Gyu; Hong, Hyun Sook; Choi, Deuk Lin; Park, Jai Soung; Lee, Hae Kyung; Kim, Dae Ho [Soonchunhyang University Bucheon Hospital, Bucheon (Korea, Republic of)


    To compare the accuracy of 16-slice multi-detector row computed tomographic arthrography (MDCTA) and magnetic resonance arthrography (MRA) for making the diagnosis and classification of labroligamentous injuries. This study is a prospective series that used MRA and MDCTA to examine 23 patients who complained of shoulder instability. Two radiologists independently analyzed the MRA and MDCTA. The sensitivity, specificity, accuracy, positive and negative predictive values were calculated from the arthrograms and the arthroscopic findings. The images of MDCTA and MRA corresponded with the findings on arthroscopy. Both imaging modalities had the same sensitivity for detecting Bankart lesions (n = 10, 90%) and posterior labral tears (n = 2, 50%) on McNemar test ({rho} = 1.00). For superior labrum anterior-to-posterior (SLAP) lesions, 6 MRA cases and 4 MDCTA cases corresponded with the arthroscopic findings. The difference between the sensitivities of MDCTA (66.7%) and MRA (100%) was not significant ({rho} 0.09). We suggest that the sensitivity of diagnosing labral lesions that induce shoulder instability is similar for MDCTA and MRA. MDCTA is effective for diagnosing and evaluating shoulder instability.

  8. Role of multiphasic multi-detector computed tomography (MDCT in the diagnosis and staging of solid neoplastic renal masses

    Manal H. Wahba


    Conclusion: Multiphase multislice computed tomography combined with CT angiography and CT urography have a major role in solid renal neoplastic masses’ diagnosis, characterization and differentiating benign and malignant tumors.

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

    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:


    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.

  10. Diagnostic Accuracy of 64-Slice MDCT Coronary Angiography for the Assessment of Coronary Artery Disease in Korean Patients with Type 2 Diabetes

    Jun Sung Moon


    Full Text Available BackgroundA 64-slice multidetector computed tomography (MDCT is well known to be a useful noninvasive form of angiography for the general population, but not for certain patients with diabetes. The aim of this study was to investigate the diagnostic accuracy and usefulness of 64-slice MDCT coronary angiography for detecting coronary artery disease in Korean patients with type 2 diabetes mellitus (T2DM.MethodsA total of 240 patients were included, 74 of whom had type 2 diabetes (M:F=40:33; 41.8±9.5 years. We compared significant coronary stenosis (>50% luminal narrowing in MDCT with invasive coronary angiography (ICA by segment, artery, and patient. We also evaluated the influence of obesity and coronary calcium score on MDCT accuracy.ResultsOf the 4,064 coronary segments studied, 4,062 segments (T2DM=1,109 were assessed quantitatively by both MDCT and ICA, and 706 segments (T2DM=226 were detected as a significant lesion by ICA in all patients. Sensitivity, specificity, as well as positive and negative predictive values for the presence of significant stenosis in T2DM were: by segment, 89.4%, 96.4%, 85.8%, and 97.4%, respectively; by artery (n=222, 95.1%, 92.9%, 94.4%, and 93.8%, respectively; by patients (n=74, 98.4%, 100.0%, 98.4%, and 90.0%, respectively. Regardless of presence of diabetes, there was no significant difference in diagnostic accuracy. Obesity (≥25 kg/m2 and coronary calcium score did not also affect the diagnostic accuracy of MDCT.ConclusionThe 64-slice MDCT coronary angiography was found to have similar diagnostic accuracy with ICA, regardless of diabetes. These results suggest MDCT may be helpful to reduce unnecessary invasive studies for patients with diabetes.

  11. Calculation of the Scattered Radiation Profile in 64 Slice CT Scanners Using Experimental Measurement

    Afshin Akbarzadeh


    Full Text Available Introduction: One of the most important parameters in x-ray CT imaging is the noise induced by detected scattered radiation. The detected scattered radiation is completely dependent on the scanner geometry as well as size, shape and material of the scanned object. The magnitude and spatial distribution of the scattered radiation in x-ray CT should be quantified for development of robust scatter correction techniques. Empirical methods based on blocking the primary photons in a small region are not able to extract scatter in all elements of the detector array while the scatter profile is required for a scatter correction procedure. In this study, we measured scatter profiles in 64 slice CT scanners using a new experimental measurement. Material and Methods: To measure the scatter profile, a lead block array was inserted under the collimator and the phantom was exposed at the isocenter. The raw data file, which contained detector array readouts, was transferred to a PC and was read using a dedicated GUI running under MatLab 7.5. The scatter profile was extracted by interpolating the shadowed area. Results: The scatter and SPR profiles were measured. Increasing the tube voltage from 80 to 140 kVp resulted in an 80% fall off in SPR for a water phantom (d=210 mm and 86% for a polypropylene phantom (d = 350 mm. Increasing the air gap to 20.9 cm caused a 30% decrease in SPR. Conclusion: In this study, we presented a novel approach for measurement of scattered radiation distribution and SPR in a CT scanner with 64-slice capability using a lead block array. The method can also be used on other multi-slice CT scanners. The proposed technique can accurately estimate scatter profiles. It is relatively straightforward, easy to use, and can be used for any related measurement.

  12. Data acquisition for experiments with multi-detector arrays

    A Chatterjee; Sushil Kamerkar; A K Jethra; S Padmini; M P Diwakar; S S Pande; M D Ghodgaonkar


    Experiments with multi-detector arrays have special requirements and place higher demands on computer data acquisition systems. In this contribution we discuss data acquisition systems with special emphasis on multi-detector arrays and in particular we describe a new data acquisition system, AMPS which we have developed recently which is in regular use in experiments at the Pelletron Laboratory, Mumbai. This includes the in-house development of a dedicated crate controller, PC interface card and software.

  13. Relevant incidental findings at abdominal multi-detector contrast-enhanced computed tomography:A collateral screening?

    Luca; Maria; Sconfienza; Giovanni; Mauri; Claudia; Muzzupappa; Alessandro; Poloni; Michele; Bandirali; Anastassia; Esseridou; Stefania; Tritella; Francesco; Secchi; Giovanni; Di; Leo; Francesco; Sardanelli


    AIM: To investigate the prevalence of relevant incidental findings(RIFs) detected during routine abdominal contrast-enhanced computed tomography(Ce CT).METHODS: We retrospectively evaluated the reports of a consecutive series of abdominal Ce CT studies performed between January and May 2013. For each report, patients’ age and sex, admission as inpatient or outpatient, clinical suspicion as indicated by the requesting physician, availability of a previous abdominal examination, and name of the reporting radiologist were recorded. Based on the clinical suspicion, the presence and features of any RIFs(if needing additional workup) was noted.RESULTS: One thousand forty abdominal Ce CT were performed in 949 patients(528 males, mean age 66 ±14 years). No significant difference was found between inpatients and outpatients age and sex distribution(P > 0.472). RIFs were found in 195/1040(18.8%) Ce CT [inpatients = 108/470(23.0%); outpatients = 87/570(15.2%); P = 0.002]. RIFs were found in 30/440(6.8%) Ce CT with a previous exam and in 165/600(27.5%) without a previous exam(P < 0.001). Radiologists’ distribution between inpatients or outpatients was significantly different(P < 0.001). RIFs prevalence increased with aging, except for a peak in 40-49 year group. Most involved organs were kidneys, gallbladder, and lungs.CONCLUSION: A RIF is detected in 1/5 patients undergoing abdominal Ce CT. Risk of overdiagnosis should be taken into account.

  14. Multi-detector row computed tomography of the heart: does a multi-segment reconstruction algorithm improve left ventricular volume measurements?

    Juergens, Kai Uwe; Maintz, David; Heimes, Britta; Fallenberg, Eva Maria; Heindel, Walter; Fischbach, Roman [University of Muenster, Department of Clinical Radiology, Muenster (Germany); Grude, Matthias [University of Muenster, Department of Cardiology and Angiology, Muenster (Germany); Boese, Jan M. [Siemens Medical Solutions, Forchheim (Germany)


    A multi-segment cardiac image reconstruction algorithm in multi-detector row computed tomography (MDCT) was evaluated regarding temporal resolution and determination of left ventricular (LV) volumes and global LV function. MDCT and cine magnetic resonance (CMR) imaging were performed in 12 patients with known or suspected coronary artery disease. Patients gave informed written consent for the MDCT and the CMR exam. MDCT data were reconstructed using the standard adaptive cardiac volume (ACV) algorithm as well as a multi-segment algorithm utilizing data from three, five and seven rotations. LV end-diastolic (LV-EDV) and end-systolic volumes and ejection fraction (LV-EF) were determined from short-axis image reformations and compared to CMR data. Mean temporal resolution achieved was 192{+-}24 ms using the ACV algorithm and improved significantly utilizing the three, five and seven data segments to 139{+-}12, 113{+-}13 and 96{+-}11 ms (P<0.001 for each). Mean LV-EDV was without significant differences using the ACV algorithm, the multi-segment approach and CMR imaging. Despite improved temporal resolution with multi-segment image reconstruction, end-systolic volumes were less accurately measured (mean differences 3.9{+-}11.8 ml to 8.1{+-}13.9 ml), resulting in a consistent underestimation of LV-EF by 2.3-5.4% in comparison to CMR imaging (Bland-Altman analysis). Multi-segment image reconstruction improves temporal resolution compared to the standard ACV algorithm, but this does not result in a benefit for determination of LV volume and function. (orig.)

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

    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


    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.

  16. Feasibility and accuracy of coronary imaging in elderly patients using the 64-row multi-detector computed tomography: a correlation study with conventional coronary angiography

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


    Background Elderly patients generally have higher occurrence of coronary calcification, increased heart rate and difficulty with prolonged breath-holding. The aim of our study was to investigate the feasibility and accuracy of using 64-row multi-detector computed tomography (MDCT) in the assessment of coronary artery stenoses in elderly patients. Methods One hundred and fifty two patients with suspected or known coronary artery disease were divided into 4 groups according to their age (Group A: 40-49 years,n=34; Group B: 50-59 years, n=57; Group C: 60-69 years, n=48; Group D: 70 years and above; n=13). Coronary CT angiography (CTA) using a 64-row MDCT was performed and the findings were compared with that of conventional coronary angiography (CCA).Using axial images, multi-planar reconstructions (MPR) and maximum intensity projections (MIP), coronary segments of lumen diameter = 1.5mm were analyzed for the presence of significant stenosis (= 50% ). Results Percentages of poor image quality from coronary CTA preventing reliable correlations with CCA were 21%, 14%, 19% and 62% in Groups A to D respectively. Patients in Group D had significantly higher calcium scores compared with the other groups (P<0.001). In patients where CTA images were of acceptable quality, percentages of accurate correlations with CCA were 89.8%, 93.4%, 86.6% and 78.0% for Groups A to D respectively.There were no significant difference in serum creatinine, heart rate and contrast volume between the 4 groups. Conclusions The 64-row MDCT coronary angiography was less accurate and feasible for patients aged 70 years or above due to heavy coronary calcification and inability to perform a satisfactory breath-hold. However, a high diagnostic accuracy with the MDCT is possible in patients aged less than 70 years.

  17. Pulmonary arterial hypertension in children: diagnosis using ratio of main pulmonary artery to ascending aorta diameter as determined by multi-detector computed tomography

    Caro-Dominguez, Pablo; Manson, David E. [University of Toronto, Department of Diagnostic Imaging, The Hospital for Sick Children, Department of Medical Imaging, Toronto, ON (Canada); Compton, Gregory [University of Toronto, Department of Diagnostic Imaging, The Hospital for Sick Children, Department of Medical Imaging, Toronto, ON (Canada); Epworth Hospital, Epworth Medical Imaging, Richmond, VIC (Australia); Humpl, Tilman [University of Toronto, Division of Cardiology, Department of Pediatrics, The Hospital for Sick Children, Toronto, ON (Canada)


    The ratio of the transverse diameter of the main pulmonary artery (MPA) to ascending aorta as determined at multi-detector CT is a tool that can be used to assess the pulmonary arterial size in cases of pulmonary arterial hypertension in children. To establish a ratio of MPA to ascending aorta diameter using multi-detector CT imaging suggestive of pulmonary arterial hypertension in children. We hypothesize that a defined ratio of MPA to ascending aorta is identifiable on multi-detector CT and that higher ratios can be used to reliably diagnose the presence of pulmonary arterial hypertension in children. We calculated the multi-detector CT ratio of MPA to ascending aorta diameter in 44 children with documented pulmonary arterial hypertension by right heart catheterization and in 44 age- and gender-matched control children with no predisposing factors for pulmonary arterial hypertension. We compared this multi-detector-CT-determined ratio with the MPA pressure in the study group, as well as with the ratio of MPA to ascending aorta in the control group. A threshold ratio value was calculated to accurately identify children with pulmonary arterial hypertension. Children with documented primary pulmonary arterial hypertension have a significantly higher ratio of MPA to ascending aorta (1.46) than children without pulmonary arterial hypertension (1.11). A ratio of 1.3 carries a positive likelihood of 34 and a positive predictive value of 97% for the diagnosis of pulmonary arterial hypertension. The pulmonary arteries were larger in children with pulmonary arterial hypertension than in a control group of normal children. A CT-measured ratio of MPA to ascending aorta of 1.3 should raise the suspicion of pulmonary arterial hypertension in children. (orig.)

  18. Coronary 64-slice CT angiography predicts outcome in patients with known or suspected coronary artery disease

    Gaemperli, Oliver; Valenta, Ines; Schepis, Tiziano [University Hospital Zurich NUK C 32, Cardiovascular Center, Zurich (Switzerland); Husmann, Lars; Scheffel, Hans; Desbiolles, Lotus; Leschka, Sebastian; Alkadhi, Hatem [University Hospital Zurich, Institute of Diagnostic Radiology, Zurich (Switzerland); Kaufmann, Philipp A. [University Hospital Zurich NUK C 32, Cardiovascular Center, Zurich (Switzerland); University of Zurich, Zurich Center for Integrative Human Physiology (ZIHP), Zurich (Switzerland)


    The aim of this study was to assess the prognostic value of 64-slice CT angiography (CTA) in patients with known or suspected coronary artery disease (CAD). Sixty-four-slice coronary CTA was performed in 220 patients [mean age 63 {+-} 11 years, 77 (35%) female] with known or suspected CAD. CTA images were analyzed with regard to the presence and number of coronary lesions. Patients were followed-up for the occurrence of the following clinical endpoints: death, nonfatal myocardial infarction, unstable angina, and coronary revascularization. During a mean follow-up of 14 {+-} 4 months, 59 patients (27%) reached at least one of the predefined clinical endpoints. Patients with abnormal coronary arteries on CTA (i.e., presence of coronary plaques) had a 1st-year event rate of 34%, whereas in patients with normal coronary arteries no events occurred (event rate, 0%, p < 0.001). Similarly, obstructive lesions ({>=}50% luminal narrowing) on CTA were associated with a high first-year event rate (59%) compared to patients without stenoses (3%, p < 0.001). The presence of obstructive lesions was a significant independent predictor of an adverse cardiac outcome. Sixty-four-slice CTA predicts cardiac events in patients with known or suspected CAD. Conversely, patients with normal coronary arteries on CTA have an excellent mid-term prognosis. (orig.)

  19. Detection of non-ST-elevation myocardial infarction and unstable angina in the acute setting: meta-analysis of diagnostic performance of multi-detector computed tomographic angiography

    Sarno Giovanna


    Full Text Available Abstract Background Multi-detector computed tomography angiography (MDCTA has been increasingly used in the evaluation of the coronary arteries. The purpose of this study was to review the literature on the diagnostic performance of MDCTA in the acute setting, for the detection of non-ST-elevation myocardial infarction (NSTEMI and unstable angina pectoris (UAP. Methods A Pubmed and manual search of the literature published between January 2000 and June 2007 was performed. Studies were included that compared MDCTA with clinical outcome and/or CA in patients with acute chest pain, presenting at the emergency department. More specifically, studies that only included patients with initially negative cardiac enzymes suspected of having NSTEMI or UAP were included. Summary estimates of diagnostic odds ratio (DOR, sensitivity and specificity, negative (NLR and positive likelihood ratio (PLR were calculated on a patient basis. Random-effects models and summary receiver operating curve (SROC analysis were used to assess the diagnostic performance of MDCTA with 4 detectors or more. The proportion of non assessable scans (NAP on MDCTA was also evaluated. In addition, the influence of study characteristics of each study on diagnostic performance and NAP was investigated with multivariable logistic regression. Results Nine studies totalling 566 patients, were included in the meta-analysis: one randomised trial and eight prospective cohort studies. Five studies on 64-detector MDCTA and 4 studies on MDCTA with less than 64 detectors were included (32 detectors n = 1, 16 detectors n = 2, 16 and 4 detectors n = 1. Pooled DOR was 131.81 (95%CI, 50.90–341.31. The pooled sensitivity and specificity were 0.95 (95%CI, 0.90–0.98 and 0.90 (95%CI, 0.87–0.93. The pooled NLR and PLR were 0.12 (95%CI, 0.06–0.21 and 8,60 (95%CI, 5.03–14,69. The results of the logistic regressions showed that none of the investigated variables had influence on the diagnostic

  20. Magnetic resonance imaging and multi-detector computed tomography assessment of extracellular compartment in ischemic and non-ischemic myocardial pathologies

    Maythem; Saeed; Steven; W; Hetts; Robert; Jablonowski; Mark; W; Wilson


    Myocardial pathologies are major causes of morbidity and mortality worldwide. Early detection of loss of cellular integrity and expansion in extracellular volume(ECV) in myocardium is critical to initiate effective treatment. The three compartments in healthy myocardium are: intravascular(approximately 10% of tissue volume), interstitium(approximately 15%) and intracellular(approximately 75%). Myocardial cells, fibroblasts and vascular endothelial/smooth muscle cells represent intracellular compartment and the main proteins in the interstitium are types Ⅰ/Ⅲ collagens. Microscopic studies have shown that expansion of ECV is an important feature of diffuse physiologic fibrosis(e.g., aging and obesity) and pathologic fibrosis [heart failure, aortic valve disease, hypertrophic cardiomyopathy, myocarditis, dilated cardiomyopathy, amyloidosis, congenital heart disease, aortic stenosis, restrictive cardiomyopathy(hypereosinophilic and idiopathic types), arrythmogenic right ventricular dysplasia and hypertension]. This review addresses recent advances in measuring of ECV in ischemic and non-ischemic myocardial pathologies. Magnetic resonance imaging(MRI) has the ability to characterize tissue proton relaxation times(T1, T2, and T2*). Proton relaxation times reflect the physical and chemical environments of water protons in myocardium. Delayed contrast enhanced-MRI(DE-MRI) and multi-detector computed tomography(DE-MDCT) demonstrated hyper-enhanced infarct, hypo-enhanced microvascular obstruction zone and moderately enhanced peri-infarct zone, but are limited for visualizing diffuse fibrosis and patchy microinfarct despite the increase in ECV. ECV can be measured on equilibrium contrast enhanced MRI/MDCT and MRI longitudinal relaxation time mapping. Equilibrium contrast enhanced MRI/MDCT and MRI T1 mapping is currently used, but at a lower scale, as an alternative to invasive sub-endomyocardial biopsies to eliminate the need for anesthesia, coronary catheterization and

  1. Advanced NSCLC First Pass Perfusion at 64-slice CT: Reproducibility of Volume-based Quantitative Measurement

    Jie HU


    Full Text Available Background and objective The aim of this study is to explore the reproducibility of volume-based quantitative measurement of non-small cell lung cancer (NSCLC perfusion at 64-slice CT. Methods Fourteen patients with proved advanced NSCLC were enrolled in this dynamic first pass volume-based CT perfusion (CTP study (8×5 mm collimation, and they underwent the second scan within 24 h. According to the longest diameters, those patients were classified to ≤3 cm and >3 cm groups, and each group had 7 patients. Intraclass correlation coefficient (ICC and Bland-Altman statistics were used to evaluate the reproducibility of CTP imaging. Results In both groups of advanced NSCLC, the reproducibility with BF, BV, and PS values were good (ICC >0.75 for all, but mean transit time (MTT values. For advanced NSCLC (≤3 cm, repeatability coefficient (RC values with blood flow (BF, blood volume (BV, MTT and permeability surface area product (PS values were 56%, 45%, 114%, and 78%, respectively, and the 95% change intervals of RC were -39%-53%, -29%-62%, -83%-145%, and -57%-98%, respectively. For advanced NSCLC (>3 cm, those values were 46%, 30%, 59%, and 33%, respectively, and the 95% change intervals of RC were -48%-45%, -33%-26%, -54%-64%, and -18%-48%. Conclusion There is greater reproducibility of tumor size >3 cm than that of ≤3 cm. BF and BV could be addressed for reliable clinical application in antiangiogenesis therapeutic monitoring with advanced NSCLC patients.

  2. Radiation dose and cancer risk from pediatric CT examinations on 64-slice CT: A phantom study

    Feng Shiting [Department of Radiology, The First Affiliated Hospital, Sun Yat-Sen University, Guangzhou (China); Law, Martin Wai-Ming [Department of Clinical Oncology, Queen Mary Hospital (Hong Kong); Huang Bingsheng [Department of Diagnostic Radiology, University of Hong Kong (Hong Kong); Ng, Sherry [Department of Clinical Oncology, Queen Mary Hospital (Hong Kong); Li Ziping; Meng Quanfei [Department of Radiology, The First Affiliated Hospital, Sun Yat-Sen University, Guangzhou (China); Khong, Pek-Lan, E-mail: [Department of Diagnostic Radiology, University of Hong Kong (Hong Kong)


    Objective: To measure the radiation dose from CT scans in an anthropomorphic phantom using a 64-slice MDCT, and to estimate the associated cancer risk. Materials and methods: Organ doses were measured with a 5-year-old phantom and thermoluminescent dosimeters. Four protocols; head CT, thorax CT, abdomen CT and pelvis CT were studied. Cancer risks, in the form of lifetime attributable risk (LAR) of cancer incidence, were estimated by linear extrapolation using the organ radiation doses and the LAR data. Results: The effective doses for head, thorax, abdomen and pelvis CT, were 0.7 mSv, 3.5 mSv, 3.0 mSv, 1.3 mSv respectively. The organs with the highest dose were; for head CT, salivary gland (22.33 mGy); for thorax CT, breast (7.89 mGy); for abdomen CT, colon (6.62 mGy); for pelvis CT, bladder (4.28 mGy). The corresponding LARs for boys and girls were 0.015-0.053% and 0.034-0.155% respectively. The organs with highest LARs were; for head CT, thyroid gland (0.003% for boys, 0.015% for girls); for thorax CT, lung for boys (0.014%) and breast for girls (0.069%); for abdomen CT, colon for boys (0.017%) and lung for girls (0.016%); for pelvis CT, bladder for both boys and girls (0.008%). Conclusion: The effective doses from these common pediatric CT examinations ranged from 0.7 mSv to 3.5 mSv and the associated lifetime cancer risks were found to be up to 0.16%, with some organs of higher radiosensitivity including breast, thyroid gland, colon and lungs.

  3. Accessory left atrial diverticulae: contractile properties depicted with 64-slice cine-cardiac CT.

    Killeen, Ronan P


    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.

  4. Investigation of acute lower gastrointestinal bleeding with 16- and 64-slice multidetector CT.

    Lee, S; Welman, C J; Ramsay, D


    We evaluated the usefulness of 16- and 64-slice multidetector CT (MDCT) in the detection of a bleeding site in acute lower gastrointestinal tract (GIT) haemorrhage by conducting a retrospective study of cases of presumed acute lower GIT haemorrhage imaged with CT in two teaching hospitals in an 11-month period. The patients underwent contrast enhanced CT using either a 16 or 64 MDCT. No oral contrast was used. One hundred milliliters of non-ionic intravenous contrast agent was injected at 4.5 mL/s, followed by a 60 mL saline flush at 4 mL/s through a dual head injector. Images were acquired in arterial phase with or without non-contrast and portal phase imaging with 16 x 1.5 mm or 64 x 0.625 mm collimation. Active bleeding was diagnosed by the presence of iodinated contrast extravasation into the bowel lumen on arterial phase images with attenuation greater than and distinct from the normal mucosal enhancement or focal pooling of increased attenuation contrast material within a bowel segment on portal-venous images. Further management and final diagnosis was recorded. Fourteen patients and 15 studies were reviewed. CT detected and localized a presumed bleeding site or potential causative pathology in 12 (80%) of the patients. Seven of these were supported by other investigations or surgery, while five were not demonstrated by other modalities. Eight patients had mesenteric angiography, of which only four corroborated the site of bleeding. CT did not detect the bleeding site in three patients, of which two required further investigation and definitive treatment. We propose that MDCT serves a useful role as the initial rapid investigation to triage patients presenting with lower GIT bleeding for further investigation and management.

  5. Diagnostic accuracy of 64 slice multidetector coronary computed tomographic angiography in left ventricular systolic dysfunction

    Danny Lee


    Conclusion: Sixty-four slice multidetector CCTA is a very sensitive and fairly specific noninvasive diagnostic procedure for detecting coronary stenosis in patients with chest pain regardless of LV systolic function at presentation.

  6. Multi-detector computed tomography radiation doses in the follow-up of paediatric neurosurgery patients in KwaZulu-Natal: A dosimetric audit

    Christopher T. Sikwila


    Full Text Available Background: Multi-detector computed tomography (MDCT is the preferred modality for follow-up of paediatric neurosurgery patients. Serial imaging, however, has the disadvantage of an ionising radiation burden, which may be mitigated using the ‘as low as reasonably achievable’ (ALARA principle. Objectives: The primary objectives were to determine the radiation dose exposure in paediatric patients subjected to MDCT imaging following neurosurgery and to compare these values with references in current literature. Our secondary objective was to assess the relationship between radiation dose and clinical scenario. Method: Retrospective descriptive data were collected from all paediatric postsurgical patients (n = 169 between the ages of 0 and 12 years who had their first followed-up scan in the year 2010 and were followed up for six months or less. Dose-length product (DLP and current-time product were collected from the picture archiving and communication system. Demographic data including radiology reports were collected from the hospital information system. The effective doses (ED were calculated from the corresponding DLP using age-adjusted conversion factors. For purposes of comparison with other studies, median dosimetric values were calculated and the children were grouped into three age ranges, namely younger than 3 years, 3–7 years and 8–12 years old. Results: The highest median radiation doses were noted in patients being followed-up for intracranial abscesses (1183 mGy cm in the 8–12 year age group, most of whom were female. The lowest radiation doses were for intracranial shunt follow-ups (447 mGy cm. Median values for DLP, ED and current-time product (mAs were comparable to reference doses in all three age groups. However, our study showed a much broader distribution of values with higher upper limits relative to reference values. Indications for follow-up included shunts (n = 110; 65%, intracranial abscess (n = 31; 18%, subdural

  7. Usefulness of 64-slice MDCT for follow-up of young children with coronary artery aneurysm due to Kawasaki disease: Initial experience

    Peng Yun [Imaging Center, Beijing Children' s Hospital Affiliated to Capital Medical University, 56, Nanlishi Road, Xicheng District, Beijing 100045 (China)], E-mail:; Zeng Jinjin [Imaging Center, Beijing Children' s Hospital Affiliated to Capital Medical University, 56, Nanlishi Road, Xicheng District, Beijing 100045 (China); Du Zhongdong [Pediatric Cardiovascular Department, Beijing Children' s Hospital Affiliated to Capital Medical University, 56, Nanlishi Road, Xicheng District, Beijing 100045 (China); Sun Guoqiang [Imaging Center, Beijing Children' s Hospital Affiliated to Capital Medical University, 56, Nanlishi Road, Xicheng District, Beijing 100045 (China); Guo Huling [Pediatric Cardiovascular Department, Beijing Children' s Hospital Affiliated to Capital Medical University, 56, Nanlishi Road, Xicheng District, Beijing 100045 (China)


    To evaluate the initial application and value of 64-slice multidetector computed tomography as an alternative diagnostic modality in the follow-up of young children with coronary artery aneurysm due to Kawasaki disease. Twelve boys (mean age 5.1 years, range 1.8-7.8 years) for follow-up (time range from 1.1 to 5.1 years) of known Kawasaki disease and coronary artery aneurysm underwent 64-slice MDCT ECG-gated coronary angiography. All data were acquired without breath holding. Two pediatric radiologists independently assessed image quality and the diameter of all coronary segments were measured for each patient. The number, position, shape and size of each coronary artery aneurysm were observed and compared with those of ECHO performed previously. A total of 118/156 segments permitted visualization with diagnostic image quality, the CT measurements showed good inter-observer and intra-observer reliability, coefficients were 0.93 and 0.88, respectively. A total of 30 coronary artery aneurysms were identified with measured mean of 7.5 {+-} 3.8 mm in diameter, and of 12.4 {+-} 9.1 mm in longitudinal lengths.10 tumors were small, 8 tumors were medium and 12 tumors were giant aneurysm. The affected segments included LM7/12(58.3%), 9/12(75%) of LAD1, 4/12(33.3%) of LAD2, 2/12(16.7%) of LCX1; 6/12(50%) of RCA1, 9/12(75%) of RCA2 and 4/12(33.3%) of RCA3, including affected two segments in 9 tumors and three segments in 1 tumor. Calcifications were found in 5 aneurysms and 3/5 with thrombosis; six stenotic segments were found. ECHO failed to detect 8 tumors with 2/8 in LAD, 1/8 in LCX and 5/8 in RCA, and those included 4 small aneurysms. The use of 64-slice MDCT angiography proved valuable for monitoring young children with Kawasaki disease. However, further study is necessary to specify the sensitivity and specificity of MDCT in the follow-up.

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

    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)


    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.

  9. Diagnostic Value of 64-Slice Dual-Source CT Coronary Angiography in Patients with Atrial Fibrillation: Comparison with Invasive Coronary Angiography

    Zhang, Jian Jun; Liu, Tie; Feng, Yue; Wu, Wei Feng; Mou, Cai Yun; Zhai, Li Hao [Zhejiang Hospital, Hangzhou (China)


    We wanted to evaluate the image quality and diagnostic value of 64-slice dual-source computed tomography (DSCT) coronary angiography in patients with atrial fibrillation (Afib). The coronary arteries of 22 Afib patients seen on DSCT were classified into 15 segments and the imaging quality (excellent, good, moderate and poor) and significant stenoses ({>=} 50%) were evaluated by two radiologists who were blinded to the conventional coronary angiography (CAG) results. The sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) for detecting important coronary artery stenosis were calculated. McNemar test was used to determine any significant difference between DSCT and CAG, and Cohen's Kappa statistics were calculated for the intermodality and interobserver agreement. The mean heart rate was 89 {+-} 8.3 bpm (range: 80-118 bpm). A range from 250 msec to 300 msec within the RR interval was the optimal reconstruction interval for the patients with Afib. The respective overall sensitivity, specificity, PPV and NPV values were 74%, 97%, 81% and 96% for reader 1 and 72%, 98%, 85% and 96% for reader 2. No significant difference between DSCT and CAG was found for detecting a significant stenosis (reader 1, p = 1.0; reader 2, p = 0.727). Cohen's Kappa statistics demonstrated good intermodality and interobserver agreement. 64-slice DSCT coronary angiography provides good image quality in patients with atrial fibrillation without the need for controlling the heart rate. DSCT can be used for ruling out significant stenosis in patients with atrial fibrillation with its high NPV for detecting in important stenosis.

  10. The utility of multi-detector computed tomography in the diagnosis of malignant pleural effusion in the patients with ovarian cancer

    Kim, Kyung Won [Department of Radiology and Institute of Radiation Medicine, Seoul National University College of Medicine, Seoul (Korea, Republic of); Choi, Hyuck Jae, E-mail: [Department of Radiology, Asan Medical Center, University of Ulsan, Seoul (Korea, Republic of); Kang, Sokbom; Park, Sang-Yoon; Jung, Dae Chul [Research Institute and Hospital, National Cancer Center (Korea, Republic of); Cho, Jeong Yeon [Department of Radiology and Institute of Radiation Medicine, Seoul National University College of Medicine, Seoul (Korea, Republic of); Cho, Kyung-Sik [Department of Radiology, Asan Medical Center, University of Ulsan, Seoul (Korea, Republic of); Kim, Seung Hyup [Department of Radiology and Institute of Radiation Medicine, Seoul National University College of Medicine, Seoul (Korea, Republic of)


    Purpose: The purpose of this study was to retrospectively assess possible clinical predictors of malignant pleural effusion in patients with ovarian cancer. Materials and methods: This review was performed on 38 ovarian cancer patients that showed pleural effusion in a CT scan and who underwent thoracocentesis before treatment. CT scans were obtained using a 4-channel multi-detector CT scanner. Fisher's exact test was used to determine the probability of malignant pleural effusion as a function of; amount of ascites, lymph node enlargement, amount of pleural effusion, pleural nodules, and pleural thickening. Results: Sixteen (42.1%) of the 38 patients had malignant pleural effusion and malignant pleural effusion amounts were greater than those with nonmalignant effusion. Pleural nodules were more frequently found in the malignant pleural effusion group (eight [50%] patients) than in the nonmalignant group (zero [0%] patient) (p < 0.001). Supradiaphragmatic lymph node enlargement (with short axis diameter 1 cm or more) was more frequent in malignant group (12 [75%] patients) than in the nonmalignant group (two [9.1%] patients) (p < 0.001). Conclusion: The probability of malignant pleural effusion in patients with ovarian cancer was found to be correlated with the amount of pleural effusion, the presence of pleural nodules, and supradiaphragmatic lymph node enlargement.

  11. Evaluation of MRI-based Polymer Gel Dosimetry for Measurement of CT Dose Index (CTDI on 64 slices CT Scanners

    Leaila Karimi-Afshar


    Full Text Available Introduction: Computed tomography (CT has numerous applications in clinical procedures but its main problem is its high radiation dose to the patients compared to other imaging modalities using x-ray. CT delivers approximately high doses to the nearby tissues due to the scattering effect, fan beam (beam divergence and limited collimator efficiency. The radiation dose from multi-slice scanners is greater than the single-slice scanners and since multi-slice scanners increasingly employ a wide beam, 100 mm ion chambers currently used in measuring the CTDI100, are not capable of accurately measuring the total dose profile of the slice width. Therefore, the CT dose is underestimated by using them. The purpose of this study is to measure the Computed Tomography Dose Index (CTDI of a GE multi-slice CT scanner (64-slice using polymer gel dosimetry based on MRI imaging (MRPD. CTDI is the sum of point doses along the central axis and estimates the average patient dose during CT scanning. Materials and Methods: For measuring CTDI, after designing and fabricating the phantom and preparing the MAGIC gel, MRI imaging using a 1.5 T Siemens MRI scanner was performed with the imaging parameters of ST = 2 mm, NEX = 1, TE = 20-640 ms and TR = 2000 ms. CTDI was measured with a 100 mm ion chamber (CTDI100 and also the MAGIC gel with MRPD method for 10 mm and 40 mm CT scan nominal widths. Results: Following the measurement of the CTDI100 for 10 mm and 40 mm nominal slice widths of the multi-slice scanner using both ion chamber and MAGIC gel, the results showed that the ion chamber underestimates CTDI100 by 28.71% and 14.03% compared to gel for 10 mm and 40 mm respectively. Discussion and Conclusion: It was concluded from this study that gel dosimeters have the capability to measure CTDI in wide beams of multi-slice CT scanners whereas 100 mm standard ion chamber due to its limited length is not reliable even for a 10 mm beam width. In addition, due to the 3

  12. Ascending aorta measurements as assessed by ECG-gated multi-detector computed tomography: a pilot study to establish normative values for transcatheter therapies

    Lu, Tri-Linh C.; Rizzo, Elena [University Hospital Lausanne (CHUV), Department of Radiology, Lausanne (Switzerland); Huber, Christoph H.; Segesser, Ludwig K. von [University Hospital Lausanne (CHUV), Department of Cardiovascular Surgery, Lausanne (Switzerland); Dehmeshki, Jashmid [Kingston University, Digital Imaging Research Centre, Faculty of Computing, Information Systems and Mathematics, London (United Kingdom); Qanadli, Salah D. [University Hospital Lausanne (CHUV), Department of Radiology, Lausanne (Switzerland)]|[BH-07, Centre Hospitalier Universitaire Vaudois, Service de Radiodiagnostic et de Radiologie interventionnelle, Lausanne (Switzerland)


    The aim of this study was to provide an insight into normative values of the ascending aorta in regards to novel endovascular procedures using ECG-gated multi-detector CT angiography. Seventy-seven adult patients without ascending aortic abnormalities were evaluated. Measurements at relevant levels of the aortic root and ascending aorta were obtained. Diameter variations of the ascending aorta during cardiac cycle were also considered. Mean diameters (mm) were as follows: LV outflow tract 20.3{+-}3.4, coronary sinus 34.2{+-}4.1, sino-tubular junction 29.7{+-}3.4 and mid ascending aorta 32.7{+-}3.8 with coefficients of variation (CV) ranging from 12 to 17%. Mean distances (mm) were: from the plane passing through the proximal insertions of the aortic valve cusps to the right brachio-cephalic artery (BCA) 92.6{+-}11.8, from the plane passing through the proximal insertions of the aortic valve cusps to the proximal coronary ostium 12.1{+-}3.7, and between both coronary ostia 7.2{+-}3.1, minimal arc of the ascending aorta from left coronary ostium to right BCA 52.9{+-}9.5, and the fibrous continuity between the aortic valve and the anterior leaflet of the mitral valve 14.6{+-}3.3, CV 13-43%. Mean aortic valve area was 582.0{+-}131.9 mm{sup 2}. The variation of the antero-posterior and transverse diameters of the ascending aorta during the cardiac cycle were 8.4% and 7.3%, respectively. Results showed large inter-individual variations in diameters and distances but with limited intra-individual variations during the cardiac cycle. A personalized approach for planning endovascular devices must be considered. (orig.)

  13. Non-invasive assessment of coronary artery bypass graft with retrospectively ECG-gated four-row multi-detector spiral computed tomography

    Marano, Riccardo; Storto, Maria Luigia; Maddestra, Nicola; Bonomo, Lorenzo [Department of Clinical Sciences and Bioimaging, Section of Radiology, University ' ' G. d' Annunzio' ' , Ospedale ' ' SS. Annunziata' ' , Via dei Vestini, 66100, Chieti (Italy)


    The purpose of this study was to assess the accuracy of four-row multi-detector CT (MDCT) in the evaluation of coronary artery bypass graft (CABG) in patients with at least a left internal mammary artery (LIMA) grafted to the left anterior descending artery (LAD), because of the conduit of choice in bypass surgery and the greater difficulty of evaluation with non-invasive diagnostic tools. Included in the study were 57 patients with a total of 122 grafts (95 arterial and 27 venous) who underwent MDCT (4 x 2.5-mm detector-collimation, 3-mm slice width, 1.5-mm reconstruction increment) with retrospective ECG gating. Twelve patients (21%) with high heart rates were given beta-blockers in order to obtain a heart rate {<=}70 bpm in all patients. The ECG-synchronized axial images, reconstructed in the mid-diastole, MPR, MIP and 3D-VR images were independently and blindly assessed by two radiologists for graft patency and presence of high grade stenosis. Conventional angiography was the standard of reference. MDCT correctly classified 92/94 patent grafts and 26/28 occluded grafts (sensitivity/specificity 93%/97.8%); sensitivity and specificity of MDCT for assessment of arterial grafts were 100 and 98.7% (77/78 patent grafts and 17/17 occluded grafts). Image quality was considered adequate for assessment of significant stenoses in 62/92 (67%) patent grafts, with a significant differences between LIMA and non-LIMA conduits (44/57 vs. 18/65; P=0.002), according to the coronary vessel area supplied (anterior>lateral>posterior-inferior wall; P=0.002). In the remaining 30 patent grafts (33%), the assessment of stenoses was hampered by surgical clips, calcifications and motion artifacts. Sensitivity and specificity of MDCT for detection of significant graft stenoses were 80 and 96%, respectively. Inter-observer agreement was good (K=0.73). MDCT seems to be a valuable diagnostic tool for non-invasive assessment of patency of both venous and arterial grafts. An accurate evaluation

  14. Optimal scanning protocols of 64-slice CT angiography in coronary artery stents: An in vitro phantom study

    Almutairi, Abdulrahman Marzouq [Discipline of Medical Imaging, Department of Imaging and Applied Physics, Curtin University of Technology, Perth, Western Australia (Australia); Sun Zhonghua [Discipline of Medical Imaging, Department of Imaging and Applied Physics, Curtin University of Technology, Perth, Western Australia (Australia)], E-mail:; Ng, Curtise [Discipline of Medical Imaging, Department of Imaging and Applied Physics, Curtin University of Technology, Perth, Western Australia (Australia); Al-Safran, Zakariya A.; Al-Mulla, Abeer A.; Al-Jamaan, Abdulaziz I. [Department of Medical Imaging, King Fahad Specialist Hospital, Dammam (Saudi Arabia)


    Purpose: The purpose of the study was to investigate the optimal scanning protocol of 64-slice CT angiography for assessment of coronary artery stents based on a phantom study. Materials and methods: Coronary stents with a diameter of 2.5 mm was implanted in thin plastic tubes with an inner diameter of 3.0 mm to simulate a coronary artery. The tubes were filled with iodinated contrast medium diluted to 178 HU, closed at both ends and positioned in a plastic container filled with vegetable oil (-70 to -100 HU). A series of scans were performed with a 64-slice CT scanner with the following protocols: section thickness: 0.67 mm, 1.0 mm, 1.5 mm, 2.0 mm, pitch value: 0.2, 0.3, 0.5 and reconstruction interval of 50% overlap of the section thickness. 2D axial and multiplanar reformatted images were generated to assess the visibility of stent lumen, while virtual intravascular endoscopy (VIE) was reconstructed to evaluate the artery wall and stent surface. Results: Our results showed that a scanning protocol of 1.0 mm slice thickness with a pitch of 0.3 produced acceptable images with best demonstration of the intrastent lumen and stent surface with minimal image noise or artifacts. In contrast, submillimeter scans with 0.67 mm resulted in moderate artifacts which affected visualization of the coronary lumen, in addition to the increased noise. When the section thickness increased to 1.5 mm and 2.0 mm, visualization of the artery wall and stent surface was compromised, although the intrastent lumen was still visible. Conclusion: Our in vitro study suggested that a scanning protocol of 1.0 mm section thickness with pitch of 0.3 is the optimal protocol for evaluation of coronary artery stents as it allows generation of acceptable images with better visualization of stent lumen, stent surface and coronary artery wall.

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

    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)


    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.)

  16. Accuracy of 64-slice CT angiography for the detection of functionally relevant coronary stenoses as assessed with myocardial perfusion SPECT

    Gaemperli, Oliver; Schepis, Tiziano; Koepfli, Pascal; Valenta, Ines; Soyka, Jan [University Hospital Zurich NUK C 40, Nuclear Cardiology, Cardiovascular Center, Zurich (Switzerland); Leschka, Sebastian; Desbiolles, Lotus; Husmann, Lars; Alkadhi, Hatem [University Hospital Zurich, Institute of Diagnostic Radiology, Zurich (Switzerland); Kaufmann, Philipp A. [University Hospital Zurich NUK C 40, Nuclear Cardiology, Cardiovascular Center, Zurich (Switzerland); University of Zurich, Zurich Center for Integrative Human Physiology (CIHP), Zurich (Switzerland)


    CT angiography (CTA) offers a valuable alternative for the diagnosis of CAD but its value in the detection of functionally relevant coronary stenoses remains uncertain. We prospectively compared the accuracy of 64-slice CTA with that of myocardial perfusion imaging (MPI) using {sup 99m}Tc-tetrofosmin-SPECT as the gold standard for the detection of functionally relevant coronary artery disease (CAD). MPI and 64-slice CT were performed in 100 consecutive patients. CTA lesions were analysed quantitatively and area stenoses {>=}50% and {>=}75% were compared with the MPI findings. In 23 patients, MPI perfusion defects were found (12 reversible, 13 fixed). A total of 399 coronary arteries and 1,386 segments was analysed. Eighty-four segments (6.1%) in 23 coronary arteries (5.8%) of nine patients (9.0%) were excluded owing to insufficient image quality. In the remaining 1,302 segments, quantitative CTA revealed stenoses {>=}50% in 57 of 376 coronary arteries (15.2%) and stenoses {>=}75% in 32 (8.5%) coronary arteries. Using a cut-off at {>=}75% area stenosis, CTA yielded the following sensitivity, specificity, negative (NPV) and positive predictive value (PPV), and accuracy for the detection of any (fixed and reversible) MPI defect: by patient, 75%, 90%, 93%, 68% and 87%, respectively; by artery, 76%, 95%, 99%, 50% and 94%, respectively. Sixty-four-slice CTA is a reliable tool to rule out functionally relevant CAD in a non-selected population with an intermediate pretest likelihood of disease. However, an abnormal CTA is a poor predictor of ischaemia. (orig.)

  17. Acute subarachnoid hemorrhage: using 64-slice multidetector CT angiography to ''triage'' patients' treatment

    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)


    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.)

  18. Doses of Coronary Study in 64 Channel Multi-Detector Computed Tomography : Reduced Radiation Dose According to Varity of Examnination Protocols

    Kim, Moon Chan [Dept. of Diagnostic Radiology, Samsung Medical Center, Seoul (Korea, Republic of)


    To compare radiation dose for coronary CT angiography (CTA) obtained with 6 examination protocols such as a retrospectively ECG gated helical scan, a prospectively ECG gated sequential scan, low kVp technique, and cardiac dose modulation technique. Coronary CTA was performed by using 6 current clinical protocols to evaluate effective dose and organ dose in primary beam area with anthropomorphic female phantom and glass dosimetric system in 64 channel multi-detector CT. After acquiring topograms of frontal and lateral projection with 80 kVp and 10 mA, main coronary scan was done with 0.35 sec tube rotation time, 40 mm collimation (0.625 mm x 64 ea), small scan field of view (32 cm diameter), 105 mm scan length. Heart beat rate of phantom was maintained 60 bpm in ECG gating. In constant mAs technique 120 kVp, 600 mA was used, and 100 kVp for low kVp technique. In a retrospectively ECG gated helical CT technique 0.22 pitch was used, peak mA (600 mA) was adopted in range of 40-80% of R-R interval and 120 mA (80% reduction) in others with cardiac dose modulation. And 210 mAs was used without cardiac dose modulation. In a prospectively ECG gated sequential CT technique data were acquired at 75% R-R interval (middle diastolic phase in cardiac cycle), and 120 msec additional padding of the tube-on time was used. For effective dose calculation region specific conversion factor of dose length product in thorax was used, which was recommended by EUR 16262. The mean effective dose for conventional coronary CTA without cardiac dose modulation in a retrospectively ECG gated helical scan was 17.8 mSv, and mean organ dose of heart was 103.8 mGy. With low kVp and cardiac dose modulation the mean effective dose showed 54.5% reduction, and heart dose showed 52.3% reduction, compared with that of conventional coronary CTA. And at the sequential scan(SnapShot pulse mode) under prospective ECG gating the mean effective dose was 4.9 mSv, this represents an 72.5% reduction compared with

  19. Image Quality and Radiation Dose for Prospectively Triggered Coronary CT Angiography: 128-Slice Single-Source CT versus First-Generation 64-Slice Dual-Source CT

    Gu, Jin; Shi, He-Shui; Han, Ping; Yu, Jie; Ma, Gui-Na; Wu, Sheng


    This study sought to compare the image quality and radiation dose of coronary computed tomography angiography (CCTA) from prospectively triggered 128-slice CT (128-MSCT) versus dual-source 64-slice CT (DSCT). The study was approved by the Medical Ethics Committee at Tongji Medical College of Huazhong University of Science and Technology. Eighty consecutive patients with stable heart rates lower than 70 bpm were enrolled. Forty patients were scanned with 128-MSCT, and the other 40 patients were scanned with DSCT. Two radiologists independently assessed the image quality in segments (diameter >1 mm) according to a three-point scale (1: excellent; 2: moderate; 3: insufficient). The CCTA radiation dose was calculated. Eighty patients with 526 segments in the 128-MSCT group and 544 segments in the DSCT group were evaluated. The image quality 1, 2 and 3 scores were 91.6%, 6.9% and 1.5%, respectively, for the 128-MSCT group and 97.6%, 1.7% and 0.7%, respectively, for the DSCT group, and there was a statistically significant inter-group difference (P ≤ 0.001). The effective doses were 3.0 mSv in the 128-MSCT group and 4.5 mSv in the DSCT group (P ≤ 0.001). Compared with DSCT, CCTA with prospectively triggered 128-MSCT had adequate image quality and a 33.3% lower radiation dose.

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

    Martos, R


    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.

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

    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)


    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


    Biplab Debbarma


    Full Text Available Acute pancreatitis is an acute, mainly diffuse, inflammatory process of the pancreas. Computed Tomography (CT scan is the modality of choice for diagnosis of acute pancreatitis. But non-availability of Computed Tomography (CT scan in all health facilities made detection of acute pancreatitis is problemsome. OBJECTIVES 1. To assess the diagnostic accuracy of Biochemical Markers and Trans-Abdominal Ultrasonography in comparison to Multidetector Computed Tomography in diagnosis of acute pancreatitis. 2. To compare the findings of Trans-Abdominal Ultrasonography with Multidetector Computed Tomography. MATERIALS AND METHODS 100 clinically suspected for acute pancreatitis patients were tested for abnormal biochemical markers, followed by examined by USG and then by MDCT in Radiodiagnosis Department of AGMC and GBP Hospital and findings were compared. Sensitivity, specificity, positive predictive value and negative predictive value were calculated. RESULTS The sensitivity and specificity of trans-abdominal ultrasonography was calculated as 75% (CI 64.06% - 84.01% and 100% (CI 83.16%-100%. CONCLUSION USG had similar sensitivity, but higher specificity value than serum markers (Amylase and Lipase.

  3. Optimization of the imaging quality of 64-slice CT acquisition protocol using Taguchi analysis: A phantom study.

    Pan, Lung Fa; Erdene, Erdenetsetseg; Chen, Chun Chi; Pan, Lung Kwang


    In this study, the phantom imaging quality of 64-slice CT acquisition protocol was quantitatively evaluated using Taguchi. The phantom acrylic line group was designed and assembled with multiple layers of solid water plate in order to imitate the adult abdomen, and scanned with Philips brilliance CT in order to simulate a clinical examination. According to the Taguchi L8(2(7)) orthogonal array, four major factors of the acquisition protocol were optimized, including (A) CT slice thickness, (B) the image reconstruction filter type, (C) the spiral CT pitch, and (D) the matrix size. The reconstructed line group phantom image was counted by four radiologists for three discrete rounds in order to obtain the averages and standard deviations of the line counts and the corresponding signal to noise ratios (S/N). The quantified S/N values were analyzed and the optimal combination of the four factor settings was determined to be comprised of (A) a 1-mm thickness, (B) a sharp filter type, (C) a 1.172 spiral CT pitch, and (D) a 1024×1024 matrix size. The dominant factors included the (A) filter type and the cross interaction between the filter type and CT slice thickness (A×B). The minor factors were determined to be (C) the spiral CT pitch and (D) the matrix size since neither was capable of yielding a 95% confidence level in the ANOVA test.

  4. Body physique and heart rate variability determine the occurrence of stair-step artefacts in 64-slice CT coronary angiography with prospective ECG-triggering.

    Husmann, Lars; Herzog, Bernhard A; Burkhard, Nina; Tatsugami, Fuminari; Valenta, Ines; Gaemperli, Oliver; Wyss, Christophe A; Landmesser, Ulf; Kaufmann, Philipp A


    The purpose of this study was to describe and characterize the frequency and extent of stair-step artefacts in computed tomography coronary angiography (CTCA) with prospective electrocardiogram (ECG)-triggering and to identify their determinants. One hundred and forty three consecutive patients (55 women, mean age 57 +/- 13 years) underwent 64-slice CTCA using prospective ECG-triggering. Occurrence of stair-step artefacts in CTCA of the thoracic wall and the coronary arteries was determined and maximum offset was measured. If stair-step artefacts occurred in both cases, a difference between thoracic wall and coronary artery offset of 0.6 mm or greater was attributed to additional motion of the heart. Mean effective radiation dose was 2.1 +/- 0.7 mSv (range 1.0-3.5 mSv). Eighty-nine patients (62%) had stair-step artefacts in CTCA of the coronary arteries (mean offset of 1.7 +/- 1.1 mm), while only 77 patients had thoracic wall stair-step artefacts (mean offset of 1.0 +/- 0.3 mm; significantly different, P < 0.001). Stair-step artefacts in CTCA of the thoracic wall were determined by BMI and weight (P < 0.01), while artefacts in CTCA of the coronary arteries were associated with heart rate variability (P < 0.05). Stair-step artefacts in CTCA with prospective ECG-triggering are determined by (a) motion of the entire patient during table travel, particularly in large patients and (b) by motion of the heart, particularly when heart rates are variable.

  5. Instrumentation for multi-detector arrays

    R K Bhowmik


    The new generation of detector arrays require complex instrumentation and data acquisition system to ensure increased reliability of operation, high degree of integration, software control and faster data handling capability. The main features of some of the existing multi-detector arrays like MSU 4 array, Gammasphere and Eurogam are summarized. The instrumentation for the proposed INGA array in India is discussed.

  6. Giant Choledochal Cyst Mimicking Massive Gallbladder Hydrops in an Adult Patient: Multi Detector Computed Tomography and Magnetic Resonance Imaging Findings Correlated to Gross and Histopathological Findings

    Joon-Il Choi


    Full Text Available Choledochal cysts are uncommon congenital anomalies of the biliary tree, commonly presenting in infancy, generally in the 1 st year of life. Presentation in adult life is less common, accounting for 20% of cases. A 19-year-old female patient presented to the Emergency Department with severe abdominal distension, a palpable abdominal mass, mild jaundice and low grade fever. Ultrasound, computed tomography (CT and magnetic resonance imaging of the abdomen showed a massive septated cystic lesion filling the entire abdomen with a significant mass effect on surrounding structures. Origin of the lesion was unclear and diagnosis included a giant mesenteric or duplication cyst, massive gallbladder with hydrops, biliary cystadenoma and giant choledochal cyst, among others. Final diagnosis was a Type IA choledochal cyst with massive asymmetric cystic dilatation of the extra-hepatic segments of the left hepatic duct with asymmetric dilatation of the right hepatic duct. Patient had an uneventful recovery after resection of the entire extrahepatic cyst and Roux-en-Y hepaticojejunostomy at the level of the hilum. In this article, we correlate CT and MRI findings to gross and histopathological findings of this giant Todani′s Type IA choledochal cyst.

  7. Quantification of normative ranges and baseline predictors of aortoventricular interface dimensions using multi-detector computed tomographic imaging in patients without aortic valve disease

    Gooley, Robert P., E-mail: [MonashHeart, Monash Health, Melbourne 3168 (Australia); Monash Cardiovascular Research Centre, Department of Medicine (MMC), Monash University, Melbourne 3168 (Australia); Cameron, James D., E-mail: [MonashHeart, Monash Health, Melbourne 3168 (Australia); Monash Cardiovascular Research Centre, Department of Medicine (MMC), Monash University, Melbourne 3168 (Australia); Soon, Jennifer, E-mail: [MonashHeart, Monash Health, Melbourne 3168 (Australia); Monash Cardiovascular Research Centre, Department of Medicine (MMC), Monash University, Melbourne 3168 (Australia); Loi, Duncan, E-mail: [Monash Cardiovascular Research Centre, Department of Medicine (MMC), Monash University, Melbourne 3168 (Australia); Chitale, Gauri, E-mail: [Monash Cardiovascular Research Centre, Department of Medicine (MMC), Monash University, Melbourne 3168 (Australia); Syeda, Rifath, E-mail: [Monash Cardiovascular Research Centre, Department of Medicine (MMC), Monash University, Melbourne 3168 (Australia); Meredith, Ian T., E-mail: [MonashHeart, Monash Health, Melbourne 3168 (Australia); Monash Cardiovascular Research Centre, Department of Medicine (MMC), Monash University, Melbourne 3168 (Australia)


    Highlights: • MDCT imaging of the aortoventricular interface is increasingly common. • We present normative ranges for aortoventricular interface dimensions. • Such techniques and ranges should be used to standardise reporting and research. - Abstract: Background: Multidetector computed tomographic (MDCT) assessment of the aortoventricular interface has gained increased importance with the advent of minimally invasive treatment modalities for aortic and mitral valve disease. This has included a standardised technique of identifying a plane through the nadir of each coronary cusp, the basal plane, and taking further measurements in relation to this plane. Despite this there is no published data defining normal ranges for these aortoventricular metrics in a healthy cohort. This study seeks to quantify normative ranges for MDCT derived aortoventricular dimensions and evaluate baseline demographic and anthropomorphic associates of these measurements in a normal cohort. Methods: 250 consecutive patients undergoing MDCT coronary angiography were included. Aortoventricular dimensions at multiple levels of the aortoventricular interface were assessed and normative ranges quantified. Multivariate linear regression was performed to identify baseline predictors of each metric. Results: The mean age was 59 ± 12 years. The basal plane was eccentric (EI = 0.22 ± 0.06) while the left ventricular outflow tract was more eccentric (EI = 0.32 ±0.06), with no correlation to gender, age or hypertension. Male gender, height and body mass index were consistent independent predictors of larger aortoventricular dimensions at all anatomical levels, while age was predictive of supra-annular measurements. Conclusions: Male gender, height and BMI are independent predictors of all aortoventricular dimensions while age predicts only supra-annular dimensions. Use of defined metrics such as the basal plane and formation of normative ranges for these metrics allows reference for clinical

  8. Downstream resource utilization following hybrid cardiac imaging with an integrated cadmium-zinc-telluride/64-slice CT device

    Fiechter, Michael; Kaufmann, Philipp A. [University Hospital Zurich, Department of Radiology, Cardiac Imaging, Zurich (Switzerland); University of Zurich, Zurich Center for Integrative Human Physiology (ZIHP), Zurich (Switzerland); Ghadri, Jelena R.; Wolfrum, Mathias; Kuest, Silke M.; Pazhenkottil, Aju P.; Nkoulou, Rene N.; Herzog, Bernhard A.; Gebhard, Catherine; Fuchs, Tobias A.; Gaemperli, Oliver [University Hospital Zurich, Department of Radiology, Cardiac Imaging, Zurich (Switzerland)


    Low yield of invasive coronary angiography and unnecessary coronary interventions have been identified as key cost drivers in cardiology for evaluation of coronary artery disease (CAD). This has fuelled the search for noninvasive techniques providing comprehensive functional and anatomical information on coronary lesions. We have evaluated the impact of implementation of a novel hybrid cadmium-zinc-telluride (CZT)/64-slice CT camera into the daily clinical routine on downstream resource utilization. Sixty-two patients with known or suspected CAD were referred for same-day single-session hybrid evaluation with CZT myocardial perfusion imaging (MPI) and coronary CT angiography (CCTA). Hybrid MPI/CCTA images from the integrated CZT/CT camera served for decision-making towards conservative versus invasive management. Based on the hybrid images patients were classified into those with and those without matched findings. Matched findings were defined as the combination of MPI defect with a stenosis by CCTA in the coronary artery subtending the respective territory. All patients with normal MPI and CCTA as well as those with isolated MPI or CCTA finding or combined but unmatched findings were categorized as ''no match''. All 23 patients with a matched finding underwent invasive coronary angiography and 21 (91%) were revascularized. Of the 39 patients with no match, 5 (13%, p < 0.001 vs matched) underwent catheterization and 3 (8%, p < 0.001 vs matched) were revascularized. Cardiac hybrid imaging in CAD evaluation has a profound impact on patient management and may contribute to optimal downstream resource utilization. (orig.)

  9. 东软64层CT整机研制及关键技术研发%Neusoft 64-slice CT Scanner Development with Key Technology

    马建华; 张华; 边兆英; 李双学; 赵大哲; 陈武凡


    目的:64层C T整机研制与关键技术研发。方法:按照产、学、研、医联合方式,通过原始与系统创新,攻克系统平台技术、数据采集技术、低剂量成像伪影校正及噪声抑制技术、图像重建及优化技术等多项64层C T关键技术。结果:成功研制出中国首台具有完全自主知识产权的64层CT整机,其性能指标达到国际同类产品先进水平,产品通过CCC、SFDA,CE、FDA、CB、CSA等认证。结论:东软集团的64层CT已正式进入医用CT高端市场。%Objective:developing 64-slice CT scanner with key technology research.Methods: under industry-university-research-medicine cooperation pattern, through the original and system innovation, we conquer many 64-slice CT key technologies, including system platform technology, data acquisition technology, low-dose imaging artifacts correction and noise suppression technology, image reconstruction and optimization technology and so on.Results: The developed ifrst 64-slice CT scanner of China contains ful independent intelectual property rights with international advanced levels and geting the CCC, SFDA, CE, FDA, CB, CSA certiifcations, etc.Conclusion: Neusoft 64-slice CT scanner has formaly entered the medical CT high-end market.

  10. Double Chooz Improved Multi-Detector Measurements

    CERN. Geneva


    The Double Chooz experiment (DC) is a reactor neutrino oscillation experiment running at Chooz nuclear power plant (2 reactors) in France. In 2011, DC first reported indication of non-zero θ13 with the far detector (FD) located at the maximum of oscillation effects (i.e. disappearance), thus challenging the CHOOZ non-observation limit. A robust observation of θ13 followed in 2012 by the Daya Bay experiments with multiple detector configurations. Since 2015 DC runs in a multi-detector configuration making thus the impact of several otherwise dominating systematics reduce strongly. DC’s unique almost "iso-flux" site, allows the near detector (ND) to become a direct accurate non-oscillation reference to the FD. Our first multi-detector results at MORIOND-2016 showed an intriguing deviation of θ13 with respect to the world average. We will address this issue in this seminar. The combined "reactor-θ13" measurement is expected to ...

  11. Quantitative evaluation of benign meningioma and hemangiopericytoma with peritumoral brain edema by 64-slice CT perfusion imaging

    REN Guang; CHEN Shuang; WANG Yin; ZHU Rui-jiang; GENG Dao-ying; FENG Xiao-yuan


    Background Hemangiopericytomas (HPCs) have a relentless tendency for local recurrence and metastases,differentiating between benign meningiomas and HPCs before surgery is important for both treatment planning and the prognosis appraisal.The purpose of this study was to evaluate the correlations between CT perfusion parameters and microvessel density (MVD) in extra-axial tumors and the possible role of CT perfusion imaging in preoperatively differentiating benign meningiomas and HPCs.Methods Seventeen patients with benign meningiomas and peritumoral edema, 12 patients with HPCs and peritumoral edema underwent 64-slice CT perfusion imaging pre-operation.Perfusion was calculated using the Patlak method.The quantitative parameters, include cerebral blood volume (CBV), permeability surface (PS) of parenchyma, peritumoral edema among benign meningiomas and HPCs were compared respectively.CBV and PS in parenchyma, peritumoral edema of benign meningiomas and HPCs were also compared to that of the contrallateral normal white matter respectively.The correlations between CBV, PS of tumoral parenchyma and MVD were examined.Results The value of CBV and PS in parenchyma of HPCs were significantly higher than that of benign meningiomas (P<0.05), while the values of CBV and PS in peritumoral edema of benign meningiomas and HPCs were not significantly different (P >0.05).MVD in parenchyma of HPCs were significantly higher than that of benign meningiomas (P<0.05).There were positive correlations between CBV and MVD (r=0.648, P<0.05), PS and MVD (r=0.541, P<0.05) respectively.Furthermore, the value of CBV and PS in parenchyma of benign meningiomas and HPCs were significantly higher than that of contrallateral normal white matter (P<0.05), the value of CBV in peritumoral edema of benign meningiomas and HPCs were significantly lower than that of contrallateral normal white matter (P<0.05), while the value of PS in peritumoral edema of benign meningiomas and HPCs were not

  12. Interobserver agreement in fusion status assessment after instrumental desis of the lower lumbar spine using 64-slice multidetector computed tomography

    Laoutliev, Borislav; Havsteen, Inger; Bech, Birthe Højlund;


    Persistent lower back pain after instrumental posterolateral desis may arise from incomplete fusion. We investigate the impact of experience on interobserver agreement in fusion estimation.......Persistent lower back pain after instrumental posterolateral desis may arise from incomplete fusion. We investigate the impact of experience on interobserver agreement in fusion estimation....

  13. 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.

    Cui, Y; Huang, M; Zheng, J; Li, J; Liu, H; Liang, C


    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.

  14. New Progress of Post 64 Slice CT for Coronary Artery%后64排螺旋CT冠脉检查新进展

    赵义芹; 祖德贵; 曾庆玉


    64排CT冠状动脉成像已成为冠脉病变诊断及筛查的重要无创性检查,但心律不齐、心动过速、钙化支架伪影仍影响其冠脉成像质量以及辐射剂量过高。本文总结了后64排CT如双源CT、Brilliance ICT、宝石CT、320排CT在上述检查中取得的进展和仍然存在的不足,表明后64排CT的辐射剂量均有所减低,双源CT、Brilliance ICT随着时间分辨率的提高基本上解决了心动过速的问题,320排CT根本上解决了心律不齐的问题,并对后64排螺旋CT冠脉检查的发展前景进行讨论。%64-slice CT coronary artery imaging has gradually become the important noninvasive test of diagnosis and screening for coronary artery disorder,whose quality is still limited by cardiac arrhythmia,tachycardia,calcification and stents,and it has excessive radiation dose.The paper sums up the progress and disadvantage of post 64 Slice CT such as dual CT,Brilliance ICT,Gemstone CT,and 320 slice CT,shows the radiation dose has been cut down,indicates that tachycardia is settled essentially in Dual CT and Brilliance ICT with the improvement of temporal resolution and cardiac arrhythmia is resolved radically in 320 slice CT,at last,discusses the investigative foreground of post 64 Slice CT for coronary artery.

  15. Acute chest pain in emergency room. Preliminary findings with 40-64-slice CT ECG-gated of the whole chest.

    Coche, E


    ECG-gated MDCT of the entire chest represents the latest technical advance in the diagnostic work-up of atypical chest pain. The authors report their preliminary experience with the use of 40 and 64-slice CT in the emergency room and recommend to study only patients with moderate likelihood of coronary artery disease. ECG-gated MDCT of the entire chest will be preferentially performed on 64-slice MDCT rather than 40-slice MDCT because it enable to reduce the scan time (18 seconds versus 28 seconds acquisition time), the volume of contrast medium (82 mL + 15 mL versus 97 mL + 15 mL of highly concentrated contrast agent for a patient of 70 kgs) and radiation exposure (17 mSv versus 19 mSv). Approximately 1500 to 2000 of images are produced and need to be analysed on a dedicated workstation by a radiologist expert in cardiac and thoracic disorders. At the present time, only a few studies exist in the literature showing some promising results but further large clinical studies are needed before to implement such sophisticated protocol in emergency room.

  16. Low-dose ECG-gated 64-slices helical CT angiography of the chest: evaluation of image quality in 105 patients

    D' Agostino, A.G.; Remy-Jardin, M.; Khalil, C.; Remy, J. [University Center of Lille, Department of Thoracic Imaging, Hospital Calmette, Lille (France); Delannoy-Deken, V.; Duhamel, A. [University of Lille, Department of Medical Statistics, Lille (France); Flohr, T. [Siemens Medical, Research and Development Department, CT Division, Forchheim (Germany)


    interpolation artefacts was significantly linked to a low heart rate in affected patients. The overall image quality of CT scans was rated as diagnostic in 94 patients (89.5%) while 11 examinations (10.5%) were found to be partially nondiagnostic owing to the cyclic presence of severe interpolation artefacts, which can be compensated for by additional reconstructions at a different temporal window. In these cases, interpolation artefacts could have been avoided by reducing the pitch from 0.3 to 0.2 at the expense of increased patient dose. Low-dose ECG-gated CT angiograms of the chest can be obtained in routine clinical practice with 64-slice CT technology without altering the diagnostic value of CT scans. (orig.)

  17. 64层螺旋CT尿路成像技术在泌尿系疾病中的临床应用%Clinical application of 64-slice spiral CT urography in patients with urologic diseases



    目的 探讨64层螺旋CT尿路成像技术(CTU)对泌尿系统疾病的诊断价值.比较CT尿路成像技术和静脉肾盂造影(IVP)检查诊断泌尿系统疾病的准确率.方法 总结2年来泌尿系疾病患者217例完整的临床资料,其中输尿管和肾结石87例,输尿管和肾盂肿瘤66例,膀胱肿瘤35例,肾盂源性囊肿和肾盂旁囊肿13例,肾盂输尿管连接处畸形9例,双侧巨输尿管症7例.全部进行64层螺旋CT尿路成像检查,对影像学资料进行回顾性分析.结果 217例患者中CTU和IVP检查诊断准确率分别为98.2%(213/217)、65.4%(142/217).CTU、IVP检查所用时间分别为(19.1±2.9)、(65.3±24.8)min,两者比较差异有统计学意义(P<0.05).结论 CTU可多角度观察病变局部情况,且扫描时间更短,图像分辨率更高.此检查在诊断泌尿系统疾病准确率、了解病变周围组织情况以及对梗阻远端尿路显示率方面明显优于IVP,可应用于绝大多数的泌尿系统疾病患者中.%Objective To investigate the diagnostic value of 64-slice spiral CT urography(CTU) on patients with diseases of urinary system,and compare the diagnostic accuracy of computed tomography urography(CTU) and conventional intravenous pyelography (IVP)in diagnosis of urologic disease.Methods Two hundred and seventeen patients with urinary tract diseases who presented complete clinical data over the past 2 years were reviewed.There were 87 cases of ureterolithiasis and nephrolithiasis,66 cases of cancer in ureter and pelvis,35 cases of cancer in bladder,13 cases of parapelvic cyst and pyelogenic cyst,9 cases of ureteropelvic junction obstruction(UPJO),7 cases of megaloureter.All of the cases underwent 64-slice CT urography,and the images were analyzed retrospectively.Results The accuracy of diagnosis was 98.2% (213/217) in CTU group and 65.4% (142/217) in IVP group.The examination time was (19.1 ± 2.9) rmin in CTU group and (65.3 ± 24.8) min in IVU group.There were

  18. Effect of Heart Rate and Body Mass Index on the Interscan and Interobserver Variability of Coronary Artery Calcium Scoring at Prospective ECG-Triggered 64-Slice CT

    Horiguchi, Jun; Kiguchi, Masao; Fujioka, Chikako [Hiroshima University Hospital, Hiroshima (Japan); Matsuura, Noriaki; Yamamoto, Hideya; Kitagawa, Toshiro; Ito, Katsuhide [Hiroshima University, Hiroshima (Japan)


    To test the effects of heart rate, body mass index (BMI) and noise level on interscan and interobserver variability of coronary artery calcium (CAC) scoring on a prospective electrocardiogram (ECG)-triggered 64-slice CT. One hundred and ten patients (76 patients with CAC) were scanned twice on prospective ECG-triggered scans. The scan parameters included 120 kV, 82 mAs, a 2.5 mm thickness, and an acquisition center at 45% of the RR interval. The interscan and interobserver variability on the CAC scores (Agatston, volume, and mass) was calculated. The factors affecting the variability were determined by plotting it against heart rate, BMI, and noise level (defined as the standard deviation: SD). The estimated effective dose was 1.5 {+-} 0.2 mSv. The mean heart rate was 63 {+-} 12 bpm (range, 44-101 bpm). The patient BMIs were 24.5 {+-} 4.5 kg/m{sup 2} (range, 15.5-42.3 kg/m2). The mean and median interscan variabilities were 11% and 6%, respectively by volume, and 11% and 6%, respectively, by mass. Moreover, the mean and median of the algorithms were lower than the Agatston algorithm (16% and 9%, respectively). The mean and median interobserver variability was 10% and 4%, respectively (average of algorithms). The mean noise levels were 15 {+-} 4 Hounsfield unit (HU) (range, 8-25 HU). The interscan and interobserver variability was not correlated with heart rate, BMI, or noise level. The interscan and interobserver variability of CAC on a prospective ECG-triggered 64-slice CT with high image quality and 45% of RR acquisition is not significantly affected by heart rate, BMI, or noise level. The volume or mass algorithms show reduced interscan variability compared to the Agatston scoring (p < 0.05)

  19. Evaluation of organ doses and specific k effective dose of 64-slice CT thorax examination using an adult anthropomorphic phantom

    Hashim, S.; Karim, M. K. A.; Bakar, K. A.; Sabarudin, A.; Chin, A. W.; Saripan, M. I.; Bradley, D. A.


    The magnitude of radiation dose in computed tomography (CT) depends on the scan acquisition parameters, investigated herein using an anthropomorphic phantom (RANDO®) and thermoluminescence dosimeters (TLD). Specific interest was in the organ doses resulting from CT thorax examination, the specific k coefficient for effective dose estimation for particular protocols also being determined. For measurement of doses representing five main organs (thyroid, lung, liver, esophagus and skin), TLD-100 (LiF:Mg, Ti) were inserted into selected holes in a phantom slab. Five CT thorax protocols were investigated, one routine (R1) and four that were modified protocols (R2 to R5). Organ doses were ranked from greatest to least, found to lie in the order: thyroid>skin>lung>liver>breast. The greatest dose, for thyroid at 25 mGy, was that in use of R1 while the lowest, at 8.8 mGy, was in breast tissue using R3. Effective dose (E) was estimated using three standard methods: the International Commission on Radiological Protection (ICRP)-103 recommendation (E103), the computational phantom CT-EXPO (E(CTEXPO)) method, and the dose-length product (DLP) based approach. E103 k factors were constant for all protocols, ~8% less than that of the universal k factor. Due to inconsistency in tube potential and pitch factor the k factors from CTEXPO were found to vary between 0.015 and 0.010 for protocols R3 and R5. With considerable variation between scan acquisition parameters and organ doses, optimization of practice is necessary in order to reduce patient organ dose.

  20. Preliminary Reports on the Accuracy of Coronary CT-Angiography Using 64-slice Multi-slice Spiral CT (MSCT in Iran

    "A. Arjmand Shabestari


    Full Text Available Introduction & Background: Coronary artery disease (CAD is the leading cause of death in many western countries. Its prevalence and incidence among Irani-ans particularly in the urban areas are increasing. Ac-cording to the newest Tehran annual mortality re-port, the most common cause of death in Tehran is cardiovascular disease. Diagnostic gold standard in CAD is fluoroscopic coronary angiography (FCA us-ing catheterization. Nevertheless, it is an invasive method and in recent years, some non-invasive or less-invasive imaging modalities such as MRI and CT scans have been used to investigate CAD. One of the most attractive new methods in this regard is Coro-nary CT-Angiography (CCTA, which has gained considerable attention. Multi-slice spiral CT (MSCT scanners with simultaneous acquisition of multiple (up to 64 slices in less than half a second of gantry rotation time (in our study, 0.33 second, have be-come available, resulting in minimally-invasive coro-nary artery imaging. The purpose of this study is to determine the diagnostic accuracy of a new 64-slice MSCT scanner in the diagnosis of coronary artery and/or bypass grafts occlusion or hemodynamically significant stenosis. Parients & Methods: This investigation is underway in patients undergoing elective FCA. A 64-channel per rotation MSCT scanner (Somatom Sensation 64, Siemens Medical Systems, Forchheim, Germany, with 0.6 mm collimation, 0.33 second gantry rotation time and 120 KVp was used to perform CCTA. Ap-proximately 70-90 mL of a nonionic contrast medium was injected intravenously. All coronary artery seg-ments, according to American Heart Association (AHA classification & nomenclature system were analyzed. Patients who had undergone previous coronary artery bypass grafts (CABGs, or used coro-nary stents were enrolled in the study, as well. MSCT scans were carried out within 10 days of catheteriza-tion, and the most dramatically stenotic lesions were analyzed in CCTA by a semi

  1. Bicuspid aortic valves: Diagnostic accuracy of standard axial 64-slice chest CT compared to aortic valve image plane ECG-gated cardiac CT

    Murphy, David J., E-mail: [Department of Radiology, St Vincent' s University Hospital, Elm Park, Dublin 4 (Ireland); McEvoy, Sinead H., E-mail: [Department of Radiology, St Vincent' s University Hospital, Elm Park, Dublin 4 (Ireland); Iyengar, Sri, E-mail: [Department of Radiology, Plymouth Hospitals NHS Trust, Plymouth Devon PL6 8DH (United Kingdom); Feuchtner, Gudrun, E-mail: [Department of Radiology, Innsbruck Medical University, Anichstr. 35, A-6020 Innsbruck (Austria); Cury, Ricardo C., E-mail: [Department of Radiology, Baptist Cardiac and Vascular Institute, 8900 North Kendall Drive, Miami, FL 33176 (United States); Roobottom, Carl, E-mail: [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: [Institute for Diagnostic and Interventional Radiology, University Hospital Zurich, Raemistrasse 100, CH-8091 Zurich (Switzerland); Alkadhi, Hatem, E-mail: [Institute for Diagnostic and Interventional Radiology, University Hospital Zurich, Raemistrasse 100, CH-8091 Zurich (Switzerland); Dodd, Jonathan D., E-mail: [Department of Radiology, St Vincent' s University Hospital, Elm Park, Dublin 4 (Ireland)


    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

  2. 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

    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)


    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.)

  3. Safety and efficacy of a drug regimen to control heart rate during 64-slice ECG-gated coronary CTA in children

    Rigsby, Cynthia K.; Nicholas, Angela C. [Children' s Memorial Hospital, Department of Medical Imaging, 2300 Children' s Plaza, Box 9, Chicago, IL (United States); deFreitas, R.A. [Children' s Memorial Hospital, Department of Pediatrics, Chicago, IL (United States); Leidecker, Christianne [Siemens Medical Solutions, Malvern, PA (United States); Johanek, Andrew J. [Children' s Memorial Hospital, Department of Medical Imaging, 2300 Children' s Plaza, Box 9, Chicago, IL (United States); Provena St. Joseph Medical Center, Department of Radiology, Joliet, IL (United States); Anley, Peter [Children' s Memorial Hospital, Pharmacy Department, Chicago (United States); Wang, Deli [Children' s Memorial Hospital, Biostatistical Research Department, Chicago, IL (United States); Uejima, Tetsu [Children' s Memorial Hospital, Department of Anesthesiology, Chicago, IL (United States)


    The adult practice for ECG-gated single-source 64-slice coronary CTA (CCTA) includes administering beta-blockers to reduce heart rate. There are limited data on this process in children. To evaluate the safety and efficacy of a drug regimen to decrease heart rate before performing CCTA in children. IV remifentanil and esmolol infusion were chosen to decrease heart rate in 41 children (mean age 6.5 years) while they were under general anesthesia (GA) for CCTA. Drug doses, changes in heart rate and procedural complications were recorded. CCTA image quality was graded on a scale of 1 to 5. The relationships between image quality and heart rate and image quality and age were evaluated. Patient effective radiation doses were calculated. Heart rates were lowered utilizing esmolol (4 children), remifentanil (2 children) or both (35 children); 26 children received nitroglycerin for coronary vasodilation. The mean decrease in heart rate was 26%. There were no major complications. The average image-quality score was 4.4. Higher heart rates were associated with worse image quality (r = 0.67, P < 0.0001). Older age was associated with better image quality (r = 0.66, P < 0.0001). Effective radiation doses were 0.7 to 7.0 mSv. Heart rate reduction for pediatric CCTA can be safely and effectively achieved while yielding high-quality images. (orig.)

  4. Evaluation of coronal artery stent with 64-slice MDCT high definition scan mode: a comparison with conventional 64-slice MDCT%64层CT高清模式扫描对冠状动脉支架的评估价值——与传统64层CT的对照研究

    郭小超; 邱建星; 蒋学祥; 王霄英


    Objective:To evaluate the improvement of display capability of coronary artery stent on High Definition CT (HDCT) with HI RES scan mode compared with conventional 64 slice CT. Methods: Thirty six patients (from Oct. 2010 to Dec. 2010) underwent coronary CT angiography using conventional 64 slice CT and 23 patients (from Mar. 2011 to Apr 2011) using HDCT (Discovery CT750 HD) were recruited in this study. All the patients had prior coronary stenting (73 stents for 64 slice CT;41 stents for HDCT). Seven patients of 23 (15 stents) had previous coronary artery imaging with conventional 64 slice CT. The image quality of stents was analyzed in three grades. All the images were interpreted in dependently by two experienced radiologists. Image quality,measured diameter of the stents were recorded for statistics. Im age noise and radiation dose of two CT scans were also analyzed. Results:Compared with the conventional CT,the ratios of grade 1 stent images and accessable images were higher using HDCT. The average measured diameter of stents was higher (19.9%) by using HDCT than by conventional 64 slice CT 0 = 4. 405 ,P = 0. 001). There was significant difference in ima ging quality of stents between the two CT scans (Z=-2. 830,P = 0. 005). The image noise and CTDIvol had no significant difference between the two CT scans (P>0. 05). The mean effective dose of HDCT and conventional 64 slice CT were 10. 54mSv and 13. 27mSv respectively (P = 0. 016). Conclusion:Compared with the conventional 64 slice CT,HDCT coro nary angiography with HI RES scan mode can improve the image quality of coronary stents and display the in stent lumen well with lower radiation dose.%目的:通过与传统64层CT比较,评价64层CT高清采集模式显示冠状动脉支架的价值.方法:回顾性搜集2010年10月-2010年12月于我院接受传统64层螺旋CT冠状动脉成像检查的冠状动脉支架置入术后患者36例(共73枚支架),以及2011年3月-2011年4月接受64层CT高清模式

  5. 64层螺旋CT冠状动脉成像影响因素分析%Analysis of Influential Factors of 64-slice Spiral CT Coronary Angiography



    目的 探讨64层螺旋CT冠状动脉成像的质量影响因素.方法 回顾性分析514例行64层螺旋CT冠状动脉成像的影像资料.结果 根据图像评价方法,本组优321例,占62.5%;良138例,26.8%;差55例,占10.7%,认定为检查失败.127例ECG前瞻式门控扫描检查失败21例,占16.5%;387例回顾式门控扫描检查失败34例,占8.8%.检查时心率波动≤5/min 313例,7例失败,占2.2%;6~10/min 175例,23例检查失败,占13.1%;10~20/min 26例,25例检查失败,占96.2%.检查过程中37例屏气不好,32例检查失败,占86.5%;3例扫描过程中未能控制呛咳、呃逆,检查失败;53例冠状动脉搭桥术后复查者,1例因扫描范围不足而检查失败;3例过于肥胖,1例扫描参数过低而导致检查失败.结论 充分认识64层螺旋CT冠状动脉成像检查中影响成像质量的因素,争取患者最佳配合状态,方能获得更好的图像质量,提高诊断准确性.%Objective To discuss the influential factors of image quality of 64-slice spiral CT coronary angiography (CTCA). Methods The imaging data of 514 patients with coronary artery disease were retrospectively analyzed. Results According to image evaluation method, the results were excellent in 321 patients(62.5% ), good in 138 ( 26. 8% ) , and poor and regarded as failures in 55( 10.7% ). 127 patients underwent prospective electrocardiographic (ECG) gating, but failed in 21 patients (16.5%) ; 387 patients underwent retrospective ECG gating, and failed in 34 patients (8.8%). 313 patients had heart rate fluctuation ≤5 beats per minute( BPM), among whom, 7 (2.2%) failed in examination; 175 patients had heart rate from 6 BPM to 10 BPM, among whom, 23 (13.1%) failed in examination; 26 patients had heart rate from 10 BPM to 20 BPM,among whom, 25 failed in examination; 37 patients had poor breathholding, among whom, 32(86.5% )failed in examination.3 failed in examination due to incontrollable bucking and hiccup during the

  6. 64-Slice CT Angiography in Diagnosis of Congenital Heart Disease in Children%64排CTA在小儿先天性心脏病的应用

    时胜利; 陈志平; 冯东曚


    Objective To investigate the value of 64-slice CT angiography(CTA) and post-processing(reconstruction) technique in the diagnosis of children with congenital heart disease.Methods The clinical and CT data of children with congenital heart disease undergoing CT angiography from April 2010 to March 2012 in our hospital were analyzed to summarize the diagnosis method of post-processing(reconstruction) technique.Results All 73 patients with congenital heart disease were confirmed by CT angiography,in which 40 cases were with complex congenital heart disease,17 cases with atrial septal defect,43 cases with ventricular septal defect,7 cases with patent ductus arteriosus,5 cases with pulmonary artery stenosis,1 case with congenital atresia of pulmonary artery,22 cases with right ventricular outflow tract obstruction,3 cases with anomalous pulmonary venous connection,2 cases with aortic stenosis,4 cases with persistent left superior vena cava,3 cases with right aortic arch.As compared with ultrasonography and surgical outcomes,there was no obvious difference among them.Conclusion 64-slice CT angiography and post-processing reconstruction technique has significant practical value in diagnosis of children congenital heart disease.%目的 探讨64排CTA对小儿先天性心脏病的诊断价值及后处理重建方法.方法 收集整理郑州市儿童医院2010年4月-2012年3月期间经64排心脏CTA检查患儿的临床及CT资料并进行分析,总结小儿先天性心脏病64排CTA后处理诊断方法.结果 73例经64排CTA检查的先天性心脏病患儿均能明确诊断,其中复杂先心病40例,有房间隔缺损者17例,有室间隔缺损者43例,有动脉导管未闭者7例,有肺动脉狭窄者5例,先天性肺动脉闭锁1例,有右室流出道狭窄者22例,有肺静脉异位引流者3例,有主动脉狭窄者2例,永存左上腔静脉4例,右位主动脉弓3例.与彩超及手术结果比较差异无统计学意义.结论 小儿先天性心脏病的64

  7. Validation of a new cardiac image fusion software for three-dimensional integration of myocardial perfusion SPECT and stand-alone 64-slice CT angiography

    Gaemperli, Oliver; Schepis, Tiziano; Namdar, Mehdi; Valenta, Ines [University Hospital Zurich, Nuclear Cardiology, Cardiovascular Center, Zurich (Switzerland); Kalff, Victor [Alfred Hospital, Department of Nuclear Medicine, Melbourne (Australia); Stefani, Laurent [GE Healthcare Bio-Sciences, Buc Cedex (France); Desbiolles, Lotus; Leschka, Sebastian; Husmann, Lars; Alkadhi, Hatem [University Hospital Zurich, Institute of Diagnostic Radiology, Zurich (Switzerland); Kaufmann, Philipp A. [University Hospital Zurich, Nuclear Cardiology, Cardiovascular Center, Zurich (Switzerland); University of Zurich, Zurich Center for Integrative Human Physiology (ZIHP), Zurich (Switzerland)


    Combining the functional information of SPECT myocardial perfusion imaging (SPECT-MPI) and the morphological information of coronary CT angiography (CTA) may allow easier evaluation of the spatial relationship between coronary stenoses and perfusion defects. The aim of the present study was the validation of a novel software solution for three-dimensional (3D) image fusion of SPECT-MPI and CTA. SPECT-MPI with adenosine stress/rest {sup 99m}Tc-tetrofosmin was fused with 64-slice CTA in 15 consecutive patients with a single perfusion defect and a single significant coronary artery stenosis ({>=}50% diameter stenosis). 3D fused SPECT/CT images were analysed by two independent observers with regard to superposition of the stenosed vessel onto the myocardial perfusion defect. Interobserver variability was assessed by recording the X, Y, Z coordinates for the origin of the stenosed coronary artery and the centre of the perfusion defect and measuring the distance between the two landmarks. SPECT-MPI revealed a fixed defect in seven patients, a reversible defect in five patients and a mixed defect in three patients and CTA documented a significant stenosis in the respective subtending coronary artery. 3D fused SPECT/CT images showed a match of coronary lesion and perfusion defect in each patient and the fusion process took less than 15 min. Interobserver variability was excellent for landmark detection (r = 1.00 and r = 0.99, p < 0.0001) and very good for the 3D distance between the two landmarks (r = 0.94, p < 0.001). 3D SPECT/CT image fusion is feasible, reproducible and allows correct superposition of SPECT segments onto cardiac CT anatomy. (orig.)

  8. Current State and Progress of Coronary Angiography in Multi-slice Spiral Computed Tomography Imaging Techniques%多排螺旋CT在冠状动脉成像技术中的现状与进展

    胡斌; 徐文坚; 陈海松


    多层螺旋CT( mulil slice spiral CT,MSCT)技术的进步为无创性冠状动脉造影提供了广阔的前景,临床应用备受关注.特别是64层CT的出现,空间分辨率、时间分辨率大大提高,心电门控技术及三维后处理技术拓宽了CT在冠状动脉成像中的应用范围.本文阐述了CT在冠状动脉成像技术及影响因素,并对其现状及进展情况作综述.%Multi-detector row CT imaging techniques has great potential for development of noninvasive imaging of the coronary arteries. Coronary CT angiography in clinical utility field was paid highly attention to. Especially current computed tomography (64 slice CT) techniques combine high speed and spatial resolution with electrocardiography synchronization and three-dimensional post processing technology, the scope of coronary CT angiography was widen. This review article will describe the coronary angiography technology of multi-detector row CT and the factors as they relate to the current and future role of coronary CT angiography.

  9. Clinical application value of 64 slice spiral CT in the diagnosis of upper gastrointestinal bleeding%64层螺旋CT在上消化道出血诊断中的临床应用价值分析

    王振栋; 马淑华; 黎叶芳; 袁珠


    Objective:To explore the clinical application value of 64 slice spiral CT in the diagnosis of upper gastrointestinal bleeding.Methods:70 patients with upper gastrointestinal bleeding were selected.They were given x-ray barium meal examination and 64 slice spiral CT examination.We compared the test results of two kinds.Results:The detection rate of 64 slice spiral CT was 100%,and the detection rate of X-ray was 95.71%(P<0.05).The consistent rate of CT diagnosis of bleeding was 100%,which was significantly better than 85.71% of X-ray(P<0.05).Conclusion:The clinical application value of 64 slice spiral CT in the diagnosis of upper gastrointestinal bleeding was significant.%目的:探讨64层螺旋CT在上消化道出血诊断中的临床应用价值。方法:收治上消化道出血患者70例,均接受 X 线钡餐检查和64层螺旋 CT检查,比较两种检查结果。结果:64层螺旋 CT检出率100%,X 线检出率95.71%(P<0.05)。CT诊断出血原因相符率100%,显著优于X线的85.71%(P<0.05)。结论:64层螺旋CT在上消化道出血诊断中的临床应用价值显著。

  10. Volumetric evaluation of dual-energy perfusion CT by the presence of intrapulmonary clots using a 64-slice dual-source CT

    Okada, Munemasa; Nakashima, Yoshiteru; Kunihiro, Yoshie; Nakao, Sei; Matsunaga, Naofumi [Dept. of Radiology, Yamaguchi Univ. Graduate School of Medicine, Yamaguchi (Japan)], e-mail:; Morikage, Noriyasu [Medical Bioregulation Dept. of Organ Regulatory Surgery, Yamaguchi Univ. Graduate School of Medicine, Yamaguchi (Japan); Sano, Yuichi [Dept. of Radiology, Yamaguchi Univ. Hospital, Yamaguchi (Japan); Suga, Kazuyoshi [Dept. of Radiology, St Hills Hospital, Yamaguchi (Japan)


    Background: Dual-energy perfusion CT (DE{sub p}CT) directly represents the iodine distribution in lung parenchyma and low perfusion areas caused by intrapulmonary clots (IPCs) are visualized as low attenuation areas. Purpose: To evaluate if volumetric evaluation of DE{sub p}CT can be used as a predictor of right heart strain by the presence of IPCs. Material and Methods: One hundred and ninety-six patients suspected of having acute pulmonary embolism (PE) underwent DE{sub p}CT using a 64-slice dual-source CT. DE{sub p}CT images were three-dimensionally reconstructed with four threshold ranges: 1-120 HU (V{sub 120}), 1-15 HU (V{sub 15}), 1-10 HU (V{sub 10}), and 1-5 HU (V{sub 5}). Each relative ratio per V{sub 120} was expressed as the %V{sub 15}, %V{sub 10}, and %V{sub 5}. Volumetric data-sets were compared with D-dimer, pulmonary arterial (PA) pressure, right ventricular (RV) diameter, RV/left ventricular (RV/LV) diameter ratio, PA diameter, and PA/aorta (PA/Ao) diameter ratio. The areas under the ROC curves (AUCs) were examined for their relationship to the presence of IPCs. This study was approved by the local ethics committee. Results: PA pressure and D-dimer were significantly higher in the patients who had IPCs. In the patients with IPCs, V{sub 15}, V{sub 10}, V{sub 5}, %V{sub 15}, %V{sub 10}, and %V{sub 5} were also significantly higher than those without IPC (P = 0.001). %V{sub 5} had a better correlation with D-dimer (r = 0.30, P < 0.001) and RV/LV diameter ratio (r = 0.27, P < 0.001), and showed a higher AUC (0.73) than the other CT measurements. Conclusion: The volumetric evaluation by DE{sub p}CT had a correlation with D-dimer and RV/LV diameter ratio, and the relative ratio of volumetric CT measurements with a lower attenuation threshold might be recommended for the analysis of acute PE.

  11. High concentration (400 mgI/mL) versus low concentration (320 mgI/mL) iodinated contrast media in multi detector computed tomography of the liver: A randomized, single centre, non-inferiority study

    Rengo, Marco, E-mail: [Department of Radiological Sciences, Oncology and Pathology, University of Rome ' SAPIENZA' , Polo Pontino, I.C.O.T., Via Franco Faggiana 34, 04100 Latina (Italy); Caruso, Damiano, E-mail: [Department of Radiological Sciences, Oncology and Pathology, University of Rome ' SAPIENZA' , Polo Pontino, I.C.O.T., Via Franco Faggiana 34, 04100 Latina (Italy); De Cecco, Carlo N., E-mail: [Department of Radiological Sciences, Oncology and Pathology, University of Rome ' SAPIENZA' , Polo Pontino, I.C.O.T., Via Franco Faggiana 34, 04100 Latina (Italy); Lucchesi, Paola, E-mail: [Department of Radiological Sciences, Oncology and Pathology, University of Rome ' SAPIENZA' , Polo Pontino, I.C.O.T., Via Franco Faggiana 34, 04100 Latina (Italy); Bellini, Davide, E-mail: [Department of Radiological Sciences, Oncology and Pathology, University of Rome ' SAPIENZA' , Polo Pontino, I.C.O.T., Via Franco Faggiana 34, 04100 Latina (Italy); Maceroni, Marco Maria, E-mail: [Department of Radiological Sciences, Oncology and Pathology, University of Rome ' SAPIENZA' , Polo Pontino, I.C.O.T., Via Franco Faggiana 34, 04100 Latina (Italy); Ferrari, Riccardo, E-mail: [Department of Radiological Sciences, San Giovanni Hospital, Via dell' Amba Aradam 9, 00184 Rome (Italy); Paolantonio, Pasquale, E-mail: [Department of Radiological Sciences, San Giovanni Hospital, Via dell' Amba Aradam 9, 00184 Rome (Italy); and others


    Objectives: To compare vascular and parenchymal contrast enhancement in multidetector computed tomography of the liver using two contrast media with different iodine concentration (Iodixanol 320 mgI/mL and Iomeprol 400 mgI/mL) and similar viscosity, using fixed total iodine volume (40 gI) and iodine delivery rate (1.6 gI/s). Methods: 110 patients were prospectively randomized into two groups. Group A received 125 mL of Iodixanol 320 and group B 100 mL of Iomeprol 400. Attenuation values were measured at the level of the aorta, portal vein and liver parenchyma on unenhanced, arterial, portal and equilibrium phases. A non inferiority test was performed on the differences between the two groups. An independent reader evaluated image quality. Results: The equivalence of the two CM was demonstrated in all measurements. Higher, but not statistically significant, attenuation values were obtained with Iomeprol 400 in the aorta during the arterial phase (305.3 HU versus 288.4 HU; P = 0.32) and with Iodixanol 320 in the liver parenchyma, during both portal (59.8 HU versus 65.5 HU; P = 0.78) and equilibrium (40.4 HU versus 41.8 HU; P = 0.55) phases. Conclusions: Iodixanol 320 and Iomeprol 400 injected at the same iodine delivery rate (1.6 gI/s) and total iodine load (40 gI) did not provide statistically significant differences in liver parenchymal and vascular contrast enhancement.

  12. Diagnostic value of 64-slice spiral CT on fatty liver combining with nodular diseases of the liver%64排螺旋CT在脂肪肝合并肝脏结节性疾病中的诊断价值

    张志强; 李孟云


    Objective To evaluate the diagnostic value of 64-slice spiral computed tomography (CT) on fatty liver combining with nodular diseases of the liver. Methods From January 2013 to August 2014,78 patients suffered from fatty liver with nodular diseases of the liver who were visited our hospital for treatment were selected as research ob-jects.All patients were performed with conventional ultrasound and 64-slice spiral CT examination.The images were read by two senior radiological doctors,which were compared and analyzed by pathological outcomes by percutaneous liver puncture biopsy guided by surgery or ultrasound.The sensitivity,specificity,positive predictive value,negative pre-dictive value and accuracy of conventional ultrasound and 64-slice spiral CT were compared. Results Among 78 pa-tients,there were 86 foci,of which 27 cases were in benign accounting for 34.62% (32 foci for 37.21%) and the rest 51 cases belonged to malignant lesions accounting for 65.38% (54 foci for 62.79%).The sensitivity,specificity,positive pre-dictive value,negative predictive value and accuracy of conventional ultrasound on fatty liver combining with nodular diseases of the liver was 76.5%,59.3%,78.0%,57.1%,70.5%,respectively,and the rates by 64-slice spiral CT was 92.2%, 92.6%,95.9%,86.2%,and 92.3% accordingly.The indexes examined by 64-slice spiral CT were much higher than those by conventional ultrasound (P<0.05 or P<0.01). Conclusion Application of 64-slice spiral CT obtains a higher sensitiv-ity,specificity,and accuracy on treating fatty liver combining with nodular diseases of the liver,which is worthy of expan-sion in clinic.%目的:探讨64排螺旋CT在脂肪肝合并肝脏结节性疾病诊断中的价值。方法选取2013年1月~2014年8月因脂肪肝合并肝脏结节性疾病在本院就诊的78例患者为研究对象。所有病例均行常规超声和64排螺旋CT检查,由2名高年资影像科医生阅片,与外科手术或者超声引导下的经皮肝脏穿刺

  13. Diagnostic value of 64-slice CT examination and multi-planar reconstruction of carpal fractures%64层螺旋CT及多平面重建对腕骨骨折的诊断价值

    王聚宝; 奚甘平; 张建福


    To investigate the value of 64-slice CT examination and multi -planar reconstruction technique in the diagno-sis of carpal fractures .Methods:A retrospective analysis of 31 patients imaging data with carpal fracture diagnosed by 64-slice CT exam-ination and multi-planar reconstruction , by comparing with conventional X -ray radiography examination .Results:31 patients in routine X-ray examination revealed 19 carpal fractures , CT and multi-planar reconstruction examination revealed 39 .There was significant difference ( P <0.05) for carpal fracture detection between the two examination .Conclusion:Compared to the conventional X -ray ex-amination, the 64-slice CT examination and multi -planar reconstruction might have important clinical significance in the diagnosis of carpal fractures .%目的:探讨64层螺旋CT及多平面重建技术在腕骨骨折诊断中的价值。方法:回顾分析31例经64层螺旋CT及多平面重建检查确诊腕骨骨折患者的影像学资料,并与常规X线摄影检查结果相对比。结果:31例患者中常规X线检查发现腕骨骨折19处,CT及多平面重建检查发现39处。两者对腕骨骨折的检出有明显差别(P<0.05)。结论:与常规X线检查相比较,64层螺旋CT及多平面重建对确诊腕骨骨折及骨折部位、类型的显示有重要的临床价值。

  14. Application of 64-slice spiral CT and post-processing technique in evaluation of Crohn's disease%64层螺旋CT检查及后处理技术在Crohn病中的应用

    沈永菊; 冷永新; 唐翠松; 汤光宇


    目的 探讨64层螺旋CT及各种后处理技术在Crohn病中的应用.方法 对32例Crohn病患者CT扫描图像进行回顾性分析,由两位资深放射科医师对原始图像进行VR、MIP、MPR后处理.结果 Crohn病的影像学表现为:(1)肠壁增厚;(2)肠壁强化;(3)肠系膜的异常改变;(4)并发症.结论 MSCT检查可清楚显示肠壁及肠腔外病变,可得到更多的解剖和血流灌注的信息,对Crohn病的诊断、判断疾病活动度及并发症有优越性.%Objective To assess the application of multiple post-processing technique of 64-slice spiral CT in diagnosis of Crohn's disease. Methods Thirty two patients with Crohn's disease confirmed by endoscopic and pathological examination underwent 64-slice spiral CT scan. The images were reconstructed with volume rendering, maximum intensity projection, multiplanar reconstruction by two senior radiologists. Results The CT features of Crohn's disease included intestinal wall thickening, enhancement of the intestinal wall, abnormal changes of the mesentery and the complicating disease. Conclusion The 64-Slice spiral CT scan provides more information of the anatomy and blood perfusion of the lesions, which has unique superiority in diagnosis of Crohn's disease and complications.

  15. Research of Multi Detectors of Neutron Spectrum in Mix Fields

    LI; Wei; CHEN; Jun; WANG; Zhi-qiang; LI; Chun-juan; LIU; Yi-na; LUO; Hai-long; ZHANG; Wei-hua


    This neutron spectrometer can be used to measure neutron spectrum and neutron equivalent dosimetry.The range of neutron spectrum is thermal-20 MeV,and the range of neutron equivalent dosimetry is 1μSv·h-1-4 mSv·h-1.The sensor head of the neutron spectrum of multi detectors in mix fields houses five gas-filled sensors and a photo-scintillator column.There are two boron tri-fluoride(BF3)and three hydrogen

  16. Hemodynamic study of hepatocellular car-cinoma nodules by multi-slice spiral computed tomographic perfusion



    Objective To analyze the 64-slice computed tomographic(CT) perfusion parameters of hepatocellular carcinoma(HCC) nodule so as to assess the diagnostic value of hemodynamic changes of HCC nodule by this perfusion

  17. Diagnostic Value of 64-slice CTA in Detection of Intracranial Aneurysm in Patients with SAH and Comparison of the CTA Results with 2D-DSA and Intraoperative Findings

    Elif Ergun


    Full Text Available Objective: To prospectively evaluate the diagnostic value of 64-slice CTA in detecting intracranial aneurysms and to compare it with 2D-DSA and/or intra-operative findings.Material and Methods: 37 cases with SAH according to unenhanced cranial CT were included in the study. A 64-slice CTA was performed to all cases immediately after the nonenhanced cranial CT. DSA was performed in 24-48 hours following CTA. CT images were reviewed by two radiologists experienced in CT vascular imaging. The DSA reader was the angiographer who performed the DSA. The results of the CTA were compared with the DSA results and/or intraoperative findings in order to determine the diagnostic efficacy of CTA in detecting intracranial aneurysms. Results: Sensitivity, specificity, positive predictive value, negative predictive value and accuracy of CTA in detecting aneurysms were 92.8%, 83.3%, 96.2%, 71.4% and 91.2% respectively. The diagnostic value of CTA in detecting intracranial aneurysms was found to be equal to DSA by Mcnemar test. Conclusion: CTA is invaluable in detecting intracranial aneurysms. It may be used as a first line modality in SAH, and DSA may be reserved for patients with negative or equivocal CTA results.

  18. 64排螺旋CT重建技术在急性阑尾炎诊断中的应用价值%application of 64-Slice Spiral CT Reconstruction Technique in diagnosis of acute appendicitis

    任春慧; 冯华; 梁爽; 曲世巍


    Objective To investigate the effectiveness of 64-slice spiral CT reconstruction technique in diagnosis of acute appendicitis. Methods Retrospective analysis of 64-slice spiral CT scan images was performed on 60 patients who underwent abdominal 64-slice spiral CT scans and were confirmed through clinical pathology as acute appendicitis sufferers. After multi-planar and curve reconstruction of all the images in the workstation, observation and analysis of appendicitis were made on the size, morphology and surrounding changes. Results Among 60 patients with acute appendicitis, 21 cases were found acute simple appendicitis, 32 superlative appendicitis, 5 appendiceal abscess, 2 appendiceal perforation. Two kinds of features - direct and indirect features could be gained from 64-slice spiral CT findings. Direct features include thickened and enlarged appendicitis(diameter> 6 mm), thickened wall of the appendicitis, appendicitis calculus. Indirect features included inflammation, abscess or inflammatory mass around the appendicitis, free intraperitoneal gas and swelling local lymph nodes. Conclusion Acute appendicitis had typical features in its CT iamges. Application of 64-slice spiral CT reconstruction techniques could have a better reveal of appendicitis and its surrounding circumstances, which significantly improved the diagnosis of appendicitis and was of great application value.%  目的探讨64排螺旋CT重建技术在急性阑尾炎诊断中的应用价值。方法对60例经临床病理证实的急性阑尾炎患者的64排螺旋CT扫描资料进行回顾性分析,所有患者行全腹部64排螺旋平扫,所得图像在工作站进行多平面及曲面重建,对阑尾的大小、形态及周围改变进行观察分析。结果60例资料中,急性单纯性阑尾炎21例、化脓性阑尾炎32例、阑尾脓肿5例、阑尾穿孔2例。64排螺旋CT直接征象为阑尾增粗、增大(直径>6 mm),阑尾壁增厚,阑尾结石;间接征象

  19. Diagnostic Significance of Lumbar Spine Bone Metastases by 64 Slice Spiral CT and Whole Body Bone Imaging%64层螺旋CT与全身骨显像对腰椎骨转移瘤的诊断意义



    目的:探讨64层螺旋CT与99Tcm-MDP全身骨显像对腰椎骨转移瘤的诊断意义。方法回顾性分析临床确诊腰椎骨转移瘤且资料完整的住院诊治27例患者49处腰椎骨转移瘤,总结分析27例患者的64层螺旋CT与99Tcm-MDP全身骨显像检查结果。比较两种检查结果的灵敏度及特异性。结果经64层螺旋CT检查示,27例患者有41处腰椎锥体破坏;经99Tcm-MDP全身骨显像检查示,23例患者有31处腰椎椎体放射性异常浓集,27例患者发现椎体外多发放射性异常浓集。64层螺旋CT检查的灵敏度为83.6%,特异性为98.6%;99Tcm-MDP全身骨显像检查的灵敏度为63.2%,特异性为96.7%。经64层螺旋CT检查示,有17例明确诊断为腰椎转移瘤,10例可疑为腰椎转移瘤;经99Tcm-MDP全身骨显像检查示,有20例明确诊断为腰椎转移瘤,7例可疑为腰椎转移瘤。结论64层螺旋CT对腰椎骨转移瘤的诊断较99Tcm-MDP全身骨显像具有更高的灵敏度,但多数患者经99Tcm-MDP全身骨显像可获得较为明确的诊断。%Objective To investigate the diagnostic significance of lumbar spine bone metastases by 64 slice spiral CT and 99Tcm-MDP whole body bone imaging. Methods 27 cases of lumbar spine bone metastases with 49 places by clinical diagnosis and with complete hospitalization data were retrospectively analyzed, and the examination results of 27 cases with 64 slice spiral CT and 99Tcm-MDP whole body bone imaging were summarized and analyzed. The sensitivity and specificity of two kinds of examination results were compared. Results The examination result of 64 slice spiral CT showed that 41 vertebrae were damaged in 27 patients, the sensitivity was 83.6%, 17 cases of lumbar spine bone metastases were confirmed by 64 slice spiral CT, 10 patients were suspected. The examination result of 99Tcm-MDP whole body bone imaging showed that 31 vertebrae had radioactive anomaly concentration in 27 patients, the

  20. Can contrast-enhanced multi-detector computed tomography replace transesophageal echocardiography for the detection of thrombogenic milieu and thrombi in the left atrial appendage. A prospective study with 124 patients; Kann die kontrastmittelverstaerkte Mehrzeilen-Computertomografie die transoesophageale Echokardiografie bei der Detektion von thrombogenem Milieu und Vorhofohrthromben ersetzen? Eine prospektive Studie mit 124 Patienten

    Homsi, R.; Luetkens, J.A.; Schild, H.H.; Naehle, C.P. [Bonn Univ. (Germany). Dept. of Radiology; Nath, B. [SHG-KLliniken Voelklingen (Germany). Dept. of Medicine I - Cardiology; Schwab, J.O. [Bonn Univ. (Germany). Dept. of Medicine I - Cardiology


    To assess the diagnostic value of contrast-enhanced multi-detector computed tomography (MD-CT) for identifying patients with left atrial appendage (LAA) thrombus or circulatory stasis. 124 patients with a history of atrial fibrillation and/or cerebral ischemia (83 men, mean age 58.6 ± 12.4 years) and with a clinical indication for MD-CT of the heart and for transesophageal echocardiography (TEE) were included in the study. LAA thrombus or thrombogenic milieu was visually identified in TEE and MD-CT. In addition, MD-CT was analyzed quantitatively measuring the Hounsfield units (HU) of the left atrium (LA), the LAA and the ascending aorta (AA), and calculating the HU ratios LAA/AA (HU [LAA/AA]) und LAA/LA (HU [LAA/LA]). Sensitivity, specificity, negative predictive value (NPV) and positive predictive value (PPV) were calculated. The prevalence of a thrombus or thrombogenic milieu as assessed by TEE was 21.8 %. The HU ratio was lower in patients with thrombus or thrombogenic milieu (HU [LAA/AA]: 0.590 ± 0.248 vs. 0.909 ± 0.141; p < 0.001 und HU [LAA/LA] 0.689 ± 0.366 vs. 1.082 ± 0.228; p < 0.001). For the diagnosis of thrombus or a thrombogenic milieu, visual analysis yielded a sensitivity of 81.5 %, a specificity of 96.9 %, a PPV of 87.5 % and a NPV of 95.2 %. By combining visual and quantitative analysis with one criterion being positive, the specificity decreased to 91.8 %, the sensitivity to 77.8 %, the PPV to 72.4 %, and the NPV to 94.9 %. Visual analysis of the LAA in the evaluation of thrombus or thrombogenic milieu yields a high NPV of 95.1 % and may especially be useful to rule out LAA thrombi in patients with contraindications for TEE. Additional calculation of HU ratios did not improve the diagnostic performance of MD-CT.

  1. 低剂量对比剂在64排螺旋CT主动脉成像中的探讨%Exploration on the use of low dose contrast medium in 64-slice CT imaging of the aorta

    付传明; 徐官珍; 陈伦刚; 徐霖; 龚晓虹; 邹建华; 陈杰


    .01 ). The blood pressure and heart rate were not significantly different in both groups. Conclusions In diagnosis of the aorta by 64 -slice spiral computed tomography, the dosage of contrast medium should be provided individually according to different weight index meanwhile clear images can be obtained to meet with the diagnosis requirement and the potential risk of contrast-induced nephropathy can be lowered.%目的探讨64排螺旋CT不同体重注射不同对比剂量在胸腹主动脉血管成像的中应用.方法临床可疑主动脉病变患者,知情同意后分A、B两组.A组20例:体重在60kg以上注射60ml时比剂+40ml生理盐水、B组20例:体重在60kg以下按1ml/kg对比注射+适量的生理盐水;两组均采用相同注射速率和浓度行对比剂浓度实时监控触发扫描,测量升主动脉、胸7(T7)及腰2(L2)水平降主动脉、主动脉分叉处CT值及血管横截面直径,并在扫描前测量患者的体重、身高、血压、心率.由两位影像诊断高级职称医师对重组主动脉及分支血管显示进行评价,并对血管强化程度、血管横截面直径、体重、身高、血压、心率数据进行统计学分析.结果两组在升主动脉、胸7(T7)及腰2(L2)水平降主动脉、主动脉分叉等处的平均CT值分别为:331.10Hu、342.52Hu、308.71Hu、299.75Hu和337.10Hu、325.59Hu、322.06Hu、308.34Hu,血管横截面平均直径为:37.40mm、25.12mm、17.91mm、15.50mm和35.20mm、23.08mm、12.37mm、11.80mm,体重为:72.50kg、49.50kg,身高为:175.70cm、150.50cm.血压为:130/78mmHg、124/78mmHg,心率76.5次/分、74.6次/分;两组间各点的平均CT值强化不具有统计学意义(p>0.05),重组血管清晰度及显示血管分支也无差异,各点的血管横截面平均直径具有统计学意义(P0.05).结论 64层螺旋CT行主动脉MSCTA检查时,个性化因人而异不同体重注射不同对比剂量可获得良好的CTA图像,并满足诊断要求,为临床提供可靠的诊断依据,还降低了CIN潜在的风险.

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

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


    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.)

  3. 64层螺旋CT血管成像在自发性蛛网膜下腔出血中的应用价值%Application value of 64 slice spiral CT angiography in spontaneous subarachnoid hemorrhage



    目的:总结、探讨64层螺旋CT血管成像在自发性蛛网膜下腔出血诊断中的应用价值。方法:收治自发性蛛网膜下腔出血患者110例,给予64层螺旋CT扫描及数字减影血管造影,再以容积再现、曲面重组、最大密度投影、多平面重组等方法处理。结果:110例 ASH 患者均经过 DSA、手术证实。动脉瘤及脑血管畸形105例,检出率95.45%,CTA 诊断符合率达100.00%。结论:64层螺旋 CT 血管成像在自发性蛛网膜下腔出血诊断中应用价值极高,可为临床疾病诊断、治疗提供有效依据。%Objective:To summarize and discuss the value of 64 slice spiral CT angiography in the diagnosis of spontaneous subarachnoid hemorrhage.Methods:110 patients with spontaneous subarachnoid hemorrhage were selected.64 slice spiral CT scanning and digital subtraction angiography were given,and then the volume rendering,surface reconstruction,maximum density projection,multi planar reconstruction and other methods were given.Results:110 cases of ASH were confirmed by DSA and operation.aneurysm and cerebral vascular malformation were 105 cases,the detection rate was 95.45% ,and the rate of CTA diagnosis was 100%.Conclusion:64 slice spiral CT angiography in the diagnosis of spontaneous subarachnoid hemorrhage is very high value.It can provide an effective basis for clinical diagnosis and treatment.

  4. Evaluation of coronary calcifications with 64-slice CT - variability of the scores and the influence of the reconstruction interval; Bestimmung des koronaren Kalzium-Scores mittels 64-Zeilen-CT - Variabilitaet der Scores und Einfluss des Rekonstruktionszeitpunktes

    Weininger, M.; Ritter, C.O.; Beer, M.; Hahn, D.; Beissert, M. [Inst. fuer Roentgendiagnostik, Universitaetsklinikum Wuerzburg (Germany)


    Purpose: To evaluate the variability of coronary calcium scores depending on the image reconstruction interval using a 64-slice CT scanner. Materials and Methods: 30 patients (18 male, 12 female; mean age 57 {+-} 9 yrs; mean heart rate 66 {+-} 10 bpm) underwent coronary calcium scoring using a 64-slice CT scanner (Somatom Sensation 64, Siemens Medical Solutions, Erlangen) and a standardized scanning protocol. Oral {beta}-blockers were administered to 12 patients with a baseline heart rate > 70 bpm. Images were reconstructed in 10 % increments from 10 - 100 % of the RR interval. Two blinded experienced observers independently calculated Agatston (AS), calcium mass (MS) and volume scores (VS) for every reconstructed image series. The results were compared to similar studies for 16-slice CT scanners. Results: The mean values and mean coefficients of variation among all patients were as follows: AS, 397 {+-} 829, 109 % MS, 88 {+-} 225, 154 % VS, 335 {+-} 669, 100 %. Regarding the reconstruction intervals, the mean coefficients of variation were as follows: 107 % (AS), 97 % (VS), 116 % (MS). No specific image reconstruction interval with statistically significant lower variability for each score could be identified. High inter-observer agreement was achieved (K = 0.98). With statistical significance (p < 0.05) 10/30 patients (pts) were able to be allocated to more than one risk group (RG): 6 pts = 2 RG; 3 pts = 3 RG; 1 pts = 4 RG. The scores for 5/30 patients were zero for at least one reconstruction interval, but further reconstructions revealed calcifications. The number of patients assignable to different risk groups was significantly lower compared to published data using a 16-slice scanner (p < 0.05). Conclusion: Coronary calcium scores determined using a 64-slice scanner display a wide range of variability depending on the image reconstruction interval as already described for 16-slice CT scanners. However, compared to previous studies, our data indicate that this

  5. 64排螺旋 CT 支气管动脉成像对咯血的诊断意义%Diagnostic significance of bronchial artery imaging by 64-slice spiral CT for hemoptysis

    舒圣捷; 赵雁鸣; 刘白鹭; 赵德利; 贾广生; 张黎黎; 王非; 王海波; 张海涛


    Objective To discuss the diagnostic value of bronchial and non-bronchial artery system by 64-slice CT bronchial artety imaging in patients with hemoptysis as the main symptom of lung disease .Methods 64-slice CT bronchial artery imaging was performed in 28 patients with hemoptysis .The resulting CT images were analysed to identify position of the bronchial and non-bronchial systemic artery .Results Bronchial arteries were shown in the CT images as follows, 43 bronchial arteries were identified on the right side and 46 on the left side; normal origin of bronchial artery accounted for 46%of the total .Twenty-three arteries of all the arter-ies originated in the non-bronchial arterial system were located on the right , and 41 on the left side .Conclusion 64-slice CT bronchial artety imaging can not only determine the location of the bronchial and non-bronchial systemic artery , but also confirm the reason of the disease with hemoptysis as the main symptom .Then, it may lay the foundation for further clinical treatment .%目的:探讨支气管和非支气管动脉系统的64排CT支气管动脉成像对以咯血为主要症状的肺部疾病的诊断价值。方法对28例咯血患者进行64排CT支气管动脉成像。分析所得的CT图像以确定支气管和非支气管系统的动脉的位置。结果 CT可见支气管动脉情况为右侧43支,左侧46支;正常起源的支气管动脉占总数的46%;起源于非支气管动脉系统的动脉中有23支位于右侧,41支位于左侧。结论64排CT支气管动脉成像不仅可以确定支气管动脉及非支气管动脉系统的血管位置,还可以明确以咯血为主要症状的疾病的病因,为临床进一步治疗奠定基础。

  6. Toroid cavity/coil NMR multi-detector

    Gerald, II, Rex E.; Meadows, Alexander D.; Gregar, Joseph S.; Rathke, Jerome W.


    An analytical device for rapid, non-invasive nuclear magnetic resonance (NMR) spectroscopy of multiple samples using a single spectrometer is provided. A modified toroid cavity/coil detector (TCD), and methods for conducting the simultaneous acquisition of NMR data for multiple samples including a protocol for testing NMR multi-detectors are provided. One embodiment includes a plurality of LC resonant circuits including spatially separated toroid coil inductors, each toroid coil inductor enveloping its corresponding sample volume, and tuned to resonate at a predefined frequency using a variable capacitor. The toroid coil is formed into a loop, where both ends of the toroid coil are brought into coincidence. Another embodiment includes multiple micro Helmholtz coils arranged on a circular perimeter concentric with a central conductor of the toroid cavity.

  7. Enhanced security for multi-detector quantum random number generators

    Marangon, Davide G.; Vallone, Giuseppe; Zanforlin, Ugo; Villoresi, Paolo


    Quantum random number generators (QRNG) represent an advanced solution for randomness generation, which is essential in every cryptographic application. In this context, integrated arrays of single-photon detectors have promising applications as QRNGs based on the spatial detection of photons. For the employment of QRNGs in cryptography, it is necessary to have efficient methods to evaluate the so-called quantum min-entropy that corresponds to the amount of the true extractable quantum randomness from the QRNG. Here, we present an efficient method that allows the estimation of the quantum min-entropy for a multi-detector QRNG. In particular, we consider a scenario in which an attacker can control the efficiency of the detectors and knows the emitted number of photons. Eventually, we apply the method to a QRNG with 103 detectors.

  8. 64排容积CT扫描在严重多发伤快速评估中的应用%Clinical application of 64-slice spiral CT scanning in fast evaluation of severe multiple trauma

    熊坤林; 龚水根; 李然; 曹红元; 张伟国


    Objective To discuss clinical value of 64-slice spiral CT scanning in fast evaluation of severe multiple trauma.Methods A retrospective study was carried out on data of 72 multiple trauma patients diagnosed with systemic 64-slice spiral CT scanning in our hospital from January 2006 to June 2008.Of all,28 patients with traffic injuries,24 with falling injuries,10 with blunt injuries,6 with stab injuries and 4 with explosive injuries.Results There were 72 multiple trauma patients with mean scanning time of 10.2 seconds.The CT scanning showed both craniocerebral and thoracic injuries in 30 patients,brain injuries in 16,thoracoabdominal injuries plus pelvic injuries in 10,extremity and brain injuries in 14 and systemic soft tissue injuries in 2.Isotropic characteristics and postprocessing function of 64-slice spiral CT scanning could accurately diagnose and evaluate injury severity of multiple trauma.Conclusions 64-slice spiral CT scanning is a fast and effective method for fast evaluating injury severity of multiple trauma,for it can not only shorten checking time,reduce movements of the patients and relieve the pain of the patients,but also can avoid defects induced by respiratory movement and provide fairly integrated imaging materials by its isotropic characteristics and pestprecessing function.%目的 探讨64排容积CT扫描在严重多发伤快速评估中的临床价值.方法 回顾性分析我院2006年1月-2008年6月收治的72例严重多发伤患者.致伤原因:交通伤28例,坠落伤24例,钝器伤10例,刀刺伤6例,爆炸伤4例.根据患者当时受伤情况及可疑损伤部位均及时行全身64排容积CT扫描.结果 本组72例严重多发伤患者中,头、胸部均有损伤30例,头部损伤16例,胸腹盆部均有损伤10例,四肢及头部损伤14例,全身软组织损伤2例.平均扫描耗时约10.2 s.64排容积CT各向同性特点和强大的后处理功能使其能准确地对组织器官的损伤情况及损伤程度进行

  9. 64层螺旋CT在消化道穿孔的诊断价值%The Value of 64 Slice Spiral CT in the Diagnosis of Digestive Tract Perforation

    孙晓霞; 郭强强; 兰国宾; 路凯; 李宝栋; 郭福庆


    Objective:To investigate the value of 64-slice spiral CT in the diagnosis of digestive tract perforation.Method:A retrospective analysis was conducted in imaging information of 76 cases confirmed by surgery in patients with digestive tract perforation.Result:In the 76 patients,the main CT signs were peritoneal effusion,free gas,surrounding cellulites or peritonitis change around the perforation and gastrointestinal wall thickening. Preoperative diagnostic accuracy was 92.0%. The correct localization rate was 81.2%.Conclusion:64 slice spiral CT in gastrointestinal perforation can timely,accurate diagnosis. It also has high value in judging the digestive tract perforation location.%目的:探讨64层螺旋CT在消化道穿孔诊断中的价值。方法:回顾性分析76例经手术证实的消化道穿孔患者的影像资料。结果:76例患者中,CT主要征象为腹腔积液、游离气体、穿孔处周围蜂窝组织炎或腹膜炎改变、胃肠壁增厚,术前正确诊断穿孔92.0%,定位正确诊断81.2%。结论:64层螺旋CT用于消化道穿孔中能够及时、准确地作出诊断,在判断消化道穿孔位置具有较高的价值。

  10. Clinical Application of Multi-Planar Reconstruction with 64-slice Spiral CT on Protrusion of Spondylolisthesis%64层螺旋CTMPR重组对腰椎滑脱的临床应用

    刘兆芹; 钱学江


    Objective To investigate the value of multi-planar reconstruction(MPR) with 64-slice spiral CT for disease of spondylolisthesis.Methods MPRimages of 100 cases with spondylolisthesis were compared at random.Results MPR images could show not the graduation of spondylolisthesis,and could demonstrate isthmicspondy lolisthesis(ISS) or degenerative lumbar spondylolisthesis,but also could show the changes of peripheral soft tissue,the facet degeneration,and soft tissue structure.Conclusion 64-slices CT MPR images has more advantages in demonstrating the reason of spondylolisthesis,and can supply the reliable information for clinical doctors,is helpful for clinical doctors to choose the appropriate therapeutic schedule.[Chinese Medical Equipment Journal,2011 ,32(4 ) : 75-76]%目的:探讨64层螺旋CT多平面重组(MPR)对腰椎滑脱的临床应用价值.方法:随机抽取100例腰椎滑脱患者的CT MPR重建图像资料.结果:MPR不仅能够显示腰椎滑脱的分度,辨别是峡部型(真性)或是退变型滑脱(假性),并且能够显示合并的腰椎间盘膨出、小关节退变及周围软组织结构改变.结论:64层螺旋CT MPR图像,有利于全面、直观地显示腰椎滑脱的原因,并且能够为临床医生提供可靠信息,有助于临床医生选择合适的治疗方案.

  11. Experimental assessment of the influence of beam hardening filters on image quality and patient dose in volumetric 64-slice X-ray CT scanners

    Ay, Mohammad Reza; Mehranian, Abolfazi; Maleki, Asghar; Ghadiri, Hossien; Ghafarian, Pardis; Zaidi, Habib


    Beam hardening filters have long been employed in X-ray Computed Tomography (CT) to preferentially absorb soft and low-energy X-rays having no or little contribution to image formation, thus allowing the reduction of patient dose and beam hardening artefacts. In this work, we studied the influence o

  12. The One-step Imaging Study of Acute Chest Pain Trilogy by 64 Slice Spiral CT%急性胸痛三联症64层螺旋CT“一站式成像”的研究

    李欣; 孙吉林; 戴国华; 付英杰; 李志远; 柳溪


    [Abstract] Objective To investigate the image quality and ability of one-time unified examination of the 64-slice spiral CT(MSCT)in showing coronary artery, pulmonary artery and aorta. Materials and Methods 60 patients with acute chest pain received unified examination of coronary artery .pulmonary artery, aorta with 64-slice MSCT using ECG-gated function respectively. The coronary artery,pulmonary artery and aorta were imaged by using a variety of reconstruction techniques compare to 50 cases with pure 64-slice MSCT coronary angiography ,30 cases with pulmonary artery imaging and 20 cases with aortic imaging. The results from the above examinations were analyzed to evaluate whether or not the quality of the images could meet the need of the clinical diagnosis. Results The average scan time of one step examination was(8.0 ± 1.5)S,and the dose of contrast medium injected was 100 ml,and the injection flow rate of 4.0 -4.5 ml/s. There was significant difference between the chest pain group and the control group in the images of the coronary artery (P 0.05;P=0.44, >0.05;P =0.068, >0.05).The image quality of the chest pain group was as good as the one of the control group. There was significant difference between two groups and intragroup in the images of the central, peripheral and whole pulmonary artery in chest pain group and the control group (P<0.01 ;P<0.01 ;P<0.01).The image quality of the chest pain group was better than the one of the control group. Conclusion The one-step examination of coronary artery .pulmonary artery,aorta by 64-slice MSCT can be finished within 10 seconds. The image quality of aorta, pulmonary artery is excellent. There is no significant difference between the image quality of the single aorta imaging and the unified examination of the MSCT,of which image quality is better than that of single pulmonary artery MSCT. The image of the coronary artery in one time unified examination is good,can meet the needs of the clinical diagnosis,but is

  13. Diagnostic Value of 64-slice CT Perfusion Imaging in Prostate Cancer and Benign Prostatic Hyperplasia%64排CT灌注成像对前列腺癌与良性前列腺增生的诊断价值

    常泰; 戴娜


    [目的]探讨前列腺64排CT灌注成像的可行性及对前列腺癌与良性前列腺增生(BPH)的诊断价值.[方法]选择经手术或穿刺病理证实的前列腺癌患者28例(A组)和BPH患者35例(B组),所有患者均行前列腺64排CT灌注扫描,比较两组灌注参数:血流量 (BF)、血容量(BV)、峰值(PE)、达峰时间(TTP)、表面通透性(PS).[结果]A组BF、BV、PE分别为(0.492±0.115) mL/(100 g·min),(0.146±0.019) mL/100 g,(33.4±5.1) HU均显著小于BPH组(1.712±0.095) mL/(100 g·min),(0.276±0.031) mL/100 g,(56.7±6.7) HU(P<0.05),TTP、PS分别为(54.2±5.6)S和(54.8±6.9)mL/(100 g·min)均显著大于BPH组(26.4±4.6)S和(20.1±4.8)mL/(100 g·min) (P<0.05).[结论]前列腺64排CT灌注成像方法可行,灌注数据获得简单快捷,能够在一定程度上反映出前列腺血流灌注变化;前列腺64排CT灌注成像能定量地提供前列腺血流信息,可无创性地辅助诊断前列腺癌和BPH.%[Objective] To explore the feasibility and diagnostic value of 64-clice CT perfusion imaging in prostate cancer(PC) and benign prostatic hyperplasia(BPH). [Methods] Twenty-eight PC patients (group A) and thirty-five BPH patients (group B) confirmed by surgery or pathology were selected. All patients were performed by 64-slice CT perfusion of prostate. The perfusion parameters such as blood flow(BF) , blood volume (BV) , peak enhancement (PE) , time to peak (TTP) and permeability surface(PS) were compared between two groups. [Results] BF, BV and PE in group A were 0. 492 ± 0. 115 mL/(100g · min),(0. 146 ± 0. 019) mL/100g and (33. 4 ± 5. 1)HU respectively, which were significantly lower than those in group B[(1. 712 ± 0.095) mL/(100 g · min),(0. 276 ± 0. 031) mL/100 g and (56. 7 ± 6. 7) HU] ( P <0. 05). TTP and PS in group A were 54. 2 ± 5. 6S and 54. 8 ± 6. 9ml/(100g · min) respectively, which were significantly higher than those in group B[(26. 4 ± 4. 6)s and (20. 1 ± 4. 8) mL/(100g · min)]( P <0. 05

  14. The analysis of diagnostic value of 64-slice spiral CT in acute mesenteric vascular embolism%64层螺旋CT对急性肠系膜血管栓塞的诊断价值分析

    张浩亮; 杜海; 武轶非; 张凤翔


    目的 探讨64层螺旋CT血管造影对急性肠系膜血管栓塞(AMI)的诊断价值.方法 回顾性分析经64层螺旋CT全腹平扫加多期动态增强扫描诊断的15例AMI.其中,肠系膜上动脉栓塞3例(完全栓塞1例,不完全栓塞2例),肠系膜上静脉栓塞12例.结果 15例AMI直接征象:动脉期显示肠系膜上动脉完全或部分充盈缺损,可诊断为肠系膜上动脉完全或部分栓塞(3例).静脉期显示肠系膜上静脉完全或部分充盈缺损,可诊断为肠系膜上静脉完全或部分栓塞(12例);间接征象“缆绳征”12例,肠系膜水肿10例,肠管壁增厚12例,肠管扩张、积液8例,肠壁强化减弱7例,其中2例可见节段性未强化区,腹水6例,肾前筋膜增厚4例,肠壁积气2例.平扫肠系膜上动脉或上静脉高密度征7例(静脉栓塞6例,动脉栓塞1例),肠系膜上静脉栓塞累及门静脉、脾静脉6例,其中4例在增强扫描时,可见肝脏异常低灌注区.结论 64层螺旋CT平扫加多期动态增强扫描对急性肠系膜血管栓塞的诊断及时准确,应作为临床怀疑肠系膜血管疾病首选检查方法,值得推广应用.%Objective To explore the diagnostic value of 64-slice spiral CT in acute mesenteric vascular embolism. Methods We retrospectively analyzed the images of 15 AMI by multiphase dynamic contrast-enhanced 64-slice spiral CT, 3 superior mesenteric artery embolization (1 completely embolization, 2 incompletely embolization), and 12 superior mesenteric vein embolization. Results The direct signs: superior mesenteric artery was full or partial filling defect in arterial phase, and superior mesenteric vein was full or partial filling defect in vein phase. Indirect sign: there were 12 cases of "stranding sign", 10 cases of mesenteric edema, 8 cases of bowel expansion and effusion, and 6 cases with ascites, 7 cases of high density for the blood vessel by CT plain scan (6 in superior mesenteric vein embolization, 1 in superior mesenteric

  15. The application value of 64-slice spiral CT in the diagnosis of occult rib fracture%64层螺旋CT在隐匿性肋骨骨折诊断中的应用价值

    迟宝权; 刘亚静; 康洁


    Objective To evaluate the diagnostic value of 64-slice spiral CT and post-reconstruction technique in the diagnosis of occult rib fracture. Methods 42 patients with suspected chest trauma and occult rib fracture were examined by 64-slice spiral CT scan. All the original images were transferred to workstation to be post-processed to obtain volume rendering ( VR ) , maximum intensity projection ( MIP), multiplanar reformation (MPR) ,curved planar reformation(CPR) images in order to reveal occult rib fractures clearly. The abilities in displaying occult rib fractures were compared among VR, MIP, MPR, and CPR. Results The comprehensive application of various reconstruction techniques could show clearly the different parts and different types of occult rib fractures. The CPR reconstruction was the best one of them in displaying occult rib fractures,as compared with MPR and VR. A total of 59 parts of occult rib fracture were diagnosed in 42 patients with chest trauma. Conclusion The 64-slice spiral CT and post-reconstruction technique to treat the images can show clearly occult rib fracture, and can meet the positioning and qualitative analysis for occult fracture ribs,so which is the preferred method for detecting occult rib fracture.%目的 探讨64层螺旋CT及其后重建技术在隐匿性肋骨骨折诊断中的临床应用价值.方法 对42例胸部外伤考虑隐匿性肋骨骨折患者,进行64层螺旋CT平扫,将所得原始数据经工作站进行图像后处理,获得容积再现(VR),最大密度投影(MIP),多平面重组(MPR)、曲面重建(CPR)图像.并比较各种重建图像对隐匿性骨折的显示能力.结果 综合运用各种后重建技术,可清晰显示不同部位、不同类型肋骨隐匿性骨折.重建以CPR技术显示效果最佳,MPR、VR次之.42例胸部外伤患者共确诊59处肋骨隐匿性骨折.结论 64层螺旋CT及其后重建技术图像显示清晰,满足对肋骨隐匿性骨折进行定位、定性分析,是肋骨隐匿性骨折检查首选方法.

  16. 64层螺旋CT对寰椎椎动脉沟环综合征的诊断价值%The diagnostic value of 64-slice spiral CT on atlas vertebral artery sulcus ring syndrome

    路明; 陈穹; 汪茂文; 王钢; 陈小昕; 虞鲲


    目的 探讨64层螺旋CT对寰椎椎动脉沟环综合征的诊断价值.方法 收集因常规颈椎正侧位X线检查发现的寰椎椎动脉沟环患者48例,进行64层螺旋CT容积扫描后,进行容积重建和多平面重建,多方位显示寰椎结构形态及寰枢关节间隙,并探讨其与临床症状之间的关系.结果 48例寰椎椎动脉沟环患者中,右侧完整环型24例,孔径(6.59±0.50)mm,左侧完整环型36例,孔径(6.19±0.49)mm,右侧不完整环型24例,左侧不完整环型12例.30例诊断为寰椎椎动脉沟环综合征,均有寰枢关节不稳及不同程度头颈转动性眩晕症状.结论 64层螺旋CT能清晰显示寰椎后弓桥的解剖结构和测量寰椎椎动脉沟环的孔径,结合对枕颈失稳的判断,对寰椎椎动脉沟环综合征具有重要的诊断价值.%Objective To explore the diagnostic value of 64-slice spiral CT on atlas vertebral artery sulcus ring syndrome.Methods The 48 atlas vertebral artery sulcus ring patients who were found by conventional anterior posterior and lateral X-ray film were collected.The 64-slice spiral CT volume scan and following volume restitution(V R)and multiplanar reconstruction(MPR)were underwent,and multi-directional structural morphology was displayed.Their relationship with clinical features were analyzed.Results Among 48 cases of atlas vertebral artery sulcus ring,24 cases were shown with right complete bridge[pore size(6.59±0.50)mm],36 cases with left complete bridge[pore size(6.19±0.49)mm],24 cases with right incomplete bridge and 12 cases with left incomplete bridge.Thirty cases were diagnosed as atlas vertebral artery sulcus ring syndrome,and all had the atlantoaxial joint asymmetry and vertigo of different degree when head and neck rotated.Conclusions The 64-slice spiral CT can clearly display the anatomical features of posterior bridge of atlas and measure the pore size of atlas vertebral artery sulcus ring,and it has important diagnostic value for atlas

  17. 门静脉系统血栓的64层螺旋CT诊断价值%The Diagnostic Value of Thrombus in Portal Vein on 64-slice Spiral CT

    韩新巍; 周朋利; 郑颖; 丁鹏绪; 路慧彬; 司江涛


    Objective To study the 64-slice spiral CT feature of the thrombus in portal vein. Materials and Methoils Noocontrast-enhanced CT and contrast enhanced CT were performed in all 15 patients. MIP,VR and MPR were used for three dimensional reconstruction. The features of the throw.bus in portal vein were analyzed. Results In 15 cases, 13 cases(83%) occurred in trunk vein,6 cases in right branch,7 cases in left branch,3 cases in splenic vein,9 cases in superior mesenterie vein. Yerdel Grade:Grade Ⅰ1 case,Grade Ⅱ10 cases, Grade Ⅲ 3 cases,GradelV 1 case. 10 cases showed high-dense in thrombus ,3 cases appeared low-dense. 12 cases presented partial filling defect, which is described as stripe and bundles in contrasted vein. All the involved vein had smooth and successive wall and had no appeared nodes protrude out at portal vein period. All the cases with thrombus showed typical track sign or line augmentation sign in involved vein wall. 12 cases displayed collateral circulation in esophag-ogastricand splenic vein, and 4 cases displayed pericholecystic and pericholedochal collateral branches. No case visualized A-P shunt. Conclusion 64-slice spiral CT can display the location, feature and cumulative branch of the thrombus in portal vein distinctly and stereoscopically. 64-slice spiral CT is very important modality for the thrombus in portal vein.%目的 探讨门静脉系统血栓(portal vein thrombosis,PVT)的64层螺旋CT表现特征.资料与方法 15例PVT行64层螺旋CT平扫和双期增强扫描,采用最大密度投影(MIP)、容积再现(VR)及多平面重组(MPR)观察其影像学特征.结果 15例中,血栓发生于门静脉(PV)主干13例,右支6例,左支7例,脾静脉(SV)3例,肠系膜上静脉(SMV)9例,其中血栓同时累及PV主干和SMV 8例,同时累及PV左右支、主干和SMV 4例,累及PV主干和右支6例,累及PV主干和左支6例,累及SV和SMV 2例,PV主干、SV、SMV三岔口处血栓1例.Yerdel分级:Ⅰ级1例,Ⅱ级10例,Ⅲ级3

  18. Comprehensive Application of 64-slice Spiral CT Scan Techniques on Diagnosis Value of Nodular Goiter%64排CT的综合运用对诊断结节性甲状腺肿价值探讨

    肖继伟; 王晓燕; 胡道予


    目的:探讨64排螺旋CT扫描技术的综合运用对结节性甲状腺肿的诊断及鉴别诊断方面的价值。方法:选择41例经过病理证实的结节性甲状腺肿,甲状腺肿瘤及其他结节性甲状腺疾病若干,全部行64排螺旋CT平扫及动态增强扫描加后续重建,观察病灶的大小、形态、密度、边缘、强化特点及有无侵犯和转移等,总结和归纳病灶的影像学表象及特征。结果:结节性甲状腺肿、甲状腺肿瘤及其他结节性甲状腺疾病在CT影像上的表现可能少部分有所重叠,但大多数趋于不同,且有一定规律可循。结论:基于64排CT扫描技术的综合运用可在很大程度上掌握结节性甲状腺肿及相似疾病的表象及特征,对结节性甲状腺肿诊断及鉴别诊断具有重要意义。%Objective:To discuss the comprehensive application of 64-slice spiral CT scan techniques on the diagnosis value of nodular goiter and its differential diagnostic value. Methods:41 cases of nodular goiter,thyroid tumors and other nodular thyroid diseases,which had been verified by pathology,were selected to conduct 64-slice spiral CT scan and dynamic contrast-enhanced scan plus follow-up reconstruction. With observing the size,shape,density,edge,enhancing char-acteristics of the lesion as well as its infringement and metastasis,imaging characteristics of the le-sion were concluded. Results:The imaging manifestations of nodular goiter,thyroid tumors and oth-er nodular thyroid diseases overlap only in small portion on CT,but mostly they are different. Con-clusion:The comprehensive application of 64-slice spiral CT scan techniques can considerably di-agnose the representations and characteristics of nodular goiter and similar diseases,which is signifi-cant to the diagnosis and differential diagnosis of nodular goiter.

  19. Assessment of perigastric veins anatomy using 64-slice spiral CT angiography with image fusion%64层螺旋CT血管成像及融合技术评价胃周静脉

    李雪华; 孙灿辉; 冯仕庭; 彭振鹏; 何裕隆; 韩方海; 李子平; 孟悛非


    To evaluate the efficacy and clinical value of 64-slice spiral CTA with image fusion on the anatomy of perigastric veins. Methods Totally 53 patients underwent abdominal 64-slice spiral CT examination. CTA of perigastric veins, arteries and stomach were reconstructed, and the images were fused with VR technique. The inflow and courses of perigastric veins were observed, as well as the spatial relationship among the perigastric veins, arteries and stomach on CTA. Moreover, the accuracy, sensitivity and specificity of preoperative CTA were detected with surgical findings as standard in 26 patients who underwent gastrectomy. Results In 53 patients, the display rate of the right gastroepiploic vein was 100% (53/53), 90. 57% (48/53) of the left gastric vein, 73. 58% (39/53) of the right gastric vein, 50. 94% (27/53) of the posterior gastric vein, 94. 34% (50/53) of the short gastric vein, 92. 45% (49/53) of the left gastroepiploic vein, and 71. 70% (38/53) of the gastrocolic trunk. The accuracy of preoperative CTA correctly identifying perigastric veins was 92. 31%—100%, the sensitivity was 90. 91%—100%, and the specificity was 100%. Conclusion 64-slice spiral CTA can clearly display perigastric veins and show the relationship among the stomach and perigastric arteries in the living body with the fused image.%目的 探讨64层螺旋CTA及融合技术对胃周静脉的显示能力和临床应用价值.方法 对53例患者行腹部64层螺旋CT扫描.采用VR技术分别重建胃周静脉、动脉和胃,并将其融合,观察胃周静脉的汇入点、走行及其与胃周动脉、胃的空间关系.将26例接受手术治疗患者的术前CTA资料与术中所见进行对比,评价64层螺旋CTA显示胃周静脉的准确率、敏感度及特异度.结果 胃网膜右静脉的显示率为100%(53/53),胃左静脉为90.57%(48/53),胃右静脉为73.58%(39/53)、胃后静脉为50.94%(27/53)、胃短静脉为94.34%(50/53)、胃网膜左静脉为92.45%(49

  20. 精益六西格玛法对64排CT检查流程的优化研究%Optimizing Study of 64 Slices CT Examination Workflow with Lean Six Sigma

    郝光远; 陈军; 魏从全; 许诗丽; 王丽; 刘文婷; 孔雀


    Objective: To study the process of 64-slices detectors CT examination in patients by the implement of Lean Six Sigma methods: In order to reduce the patients' invalid waiting time so as to raise the patient's flux. Methods Five-step method in Lean Six Sigma management system was performed and implemented. According to such segments as the time of registration, waiting for CT examination, CT examination, films printing, films collecting, CT image interpretation, taking diagnostic report, 160 patients were randomly selected to analyze the times of each segment to find the key factor of resulting in extending the whole CT examination time. Refining methods to aim directly at the factors of resulting in the whole CT examination time were prolonged were proposed to improve the conventional CT examination process. And these methods were retained to be modified and optimized to increase the performed CT scan's patients in each segment. Then, another 160 patients were randomly selected to be compared with the fore 160 patients for the total time of CT examination after the refining methods were performed. Results: The average invalid waiting time of the patients were dropped from 88.50 min to 52.30 rain with statistically difference (P〈 0.01). The Six Sigma value (Z value) was increased from -0.54 to 5.12. Conclusion: The implementing of Lean Six Sigma in the 64-slices CT examination process can shorten the patient's invalid waiting time significantly and improve the patient's flux of single 64-slices CT scanner in each work-day.%目的:运用精益六西格玛方法研究64排CT检查流程,减少患者无效等待时间,提高单台64排CT检查患者的流通量。方法:运用和实施精益六西格玛管理体系5步法,按登记时间、检查前时间、检查时间、打印时间、收片时间、报告时间、取片时间,随机抽取160名患者分析其各阶段时间,找出致患者侯检时间延长的关键因素;对传统检查流程中导致等

  1. 64层VCT首过期灌注成像对肺部结节的诊断价值%First pass phase of perfusion imaging with 64-slice VCT in diagnosis of pulmonary nodules

    舒圣捷; 黄晗; 刘白鹭; 王非; 赵雁鸣; 申秀芬


    Objective: To evaluate the diagnostic ability of first pass phase of perfusion imaging with 64-slice VCT between benign and malignant pulmonary nodules. Methods; A total of 108 patients with pulmonary nodules underwent perfusion scan with 64 slice spiral CT scanner. The parameters of CT perfusion. Including blood volume (BV), blood flow (BF). Mean transit time (MTT). Permeability surface (PS). And time-density curve (TDC). Were analyzed. The CT perfusion and enhanced parameters were compared with vascular endothelial growth factor (VEGF) expression by immunohis-tochemistry. Results: These parameter values in pulmonary malignancy nodules were highter than those in pulmonary benign nodules. The TDC appeared different for malignant and benign nodules. Conclusion: Perfusion CT can provide quantitative information about blood flow perfusion of nodules and it is meaningful to the diagnosis and differential diagnosis of pulmonary nodules.%目的:探讨首过期的64层VCT肺灌注成像对肺部结节的诊断意义.方法:对108例肺结节患者进行CT灌注扫描,测定肺结节的时间-密度曲线(TDC)、血容积(BV)、血流量(BF)、平均通过时间(MTT)和表面通透性(PS)的数值,并测量肺结节增强前的CT值、增强值和结节-动脉增强值之比(S/A).标定结节的血管内皮生长因子(VEGF),评价肺结节CT灌注和增强指数与VEGF表达的相关性.结果:肺癌的灌注指数高于肺良性结节.良、恶性结节的TDC形态不同.结论:CT肺灌注成像可定量的评价肺结节的血流灌注特点,对肺部结节有较大的诊断及鉴别诊断意义.

  2. 64排容积CT后处理技术对输尿管梗阻的诊断%64-slice volume CT post-processing techniques for the diagnosis of ureteral obstruction

    万书友; 侯明杰; 杜灵艳


    Objective To investigate the diagnostic value of post-processing technique for ureteral obstruction. Methods All cases were confirmed by surgery or clinical data. 64-slice volume CT (VCT) was performed in 90 cases with ureteral obstruction. The volume data of all patients were reconstructed with 3D reconstruction techniques in-cluding multiple planar reformation (MPR), and volume rendering technique (VR), and curved planar reformation (CPR). Results Among the 90 cases,there were 78 cases of ureteral calculus, 4 ureteral and bladder carcinomas, 2 congenital malformations,and 1 inflammatory stenosis. Conclusion 64-slice VCT and post-processing technique have unique advantage for the etiology and level diagnosis of ureteral obstruction ,which have important significance for clinical treatment programs.%目的:探讨64排螺旋CT后处理技术对输尿管梗阻的诊断价值。方法选取我院2010年6至2013年6月间90例经临床确诊输尿管梗阻病例,所有病例均行64排容积CT扫描并进行多平面重建(multipla-nar reformatting,MPR)、容积重建(volume rendering technique,VR)、曲面重建(curved planar reformation,CPR)等处理。结果90例输尿管梗阻中78例由于输尿管结石所致,邻近器官压迫5例,输尿管癌或膀胱癌4例,先天畸形2例,输尿管炎1例。结论64排容积CT平扫及多种后处理技术对输尿管梗阻病因及定位诊断具有很高的临床应用价值,对临床治疗方案的选择具有重要指导意义。

  3. Study of Relationship Between 64-slice CT Features and Chronic Rhino Sinusitis in Children with Adenoid Hypertrophy%儿童腺样体肥大的CT表现与慢性鼻-鼻窦炎的关系

    王乐秋; 张瑞迪; 隋萍萍; 马秀凤; 李丽娟


    Objective To study the relationship between 64-slice CT features and chronic rhino sinusitis in children with adenoid hypertrophy. Methods The noses of 125 children with adenoid hypertrophy were scanned by 64-slice CT. The relationship between incidence of chronic rhino sinusitis and the volume of adenoid measured by CT was analyzed statistically. Results Mild adenoid hypertrophy (A/N 0.05). While the moderate or severe hypertrophy is (A/N ≥ 0.61) more likely to cause chronic rhino sinusitis. There is positive correlation between the hypertrophy degree and the incidence of chronic rhino sinusitis(P<0.05). Conclusion The CT features of adenoid hypertrophy is closely related to chronic rhino sinusitis. It is of great significance to treat adenoid hypertrophy timely for the prevention of chronic rhino sinusitis.%目的 探讨腺样体肥大儿童中慢性鼻-鼻窦炎发病情况与其CT表现的关系.方法 对125例腺样体肥大的儿童行常规鼻部64排CT检查,统计分析慢性鼻-鼻窦炎的发生率与CT测量腺样体体积的关系.结果 腺样体轻度肥大(A/N<0.6)与慢性鼻-鼻窦炎发病与否无关(P >0.05).腺样体中重度肥大(A/N≥0.61)的患儿更易合并慢性鼻-鼻窦炎,且呈正相关关系(P <0.05).即随着腺样体肥大程度的增加,慢性鼻-鼻窦炎发病率亦增加.结论 儿童腺样体肥大CT表现与慢性鼻-鼻窦炎密切相关,及时治疗腺样体肥大对预防及治疗慢性鼻-鼻窦炎具有十分重要的意义.

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

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


    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.

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

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


    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 by somatostatin-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.

  6. 64-slice spiral CT diagnosis of juxtapapillary diverticulum of duodenum%64层螺旋CT在十二指肠乳头旁憩室中的诊断

    陈穹; 王钢; 汪茂文; 钱春锋; 姚强; 路明; 汤友英


    目的 探讨64层螺旋CT在十二指肠乳头旁憩室(JDD)中的诊断价值.方法 回顾分析经64层螺旋CT扫描发现并经消化道造影或内窥镜逆行性胆胰管造影(ERCP)证实的JDD 34例,通过后处理软件进行多平面重建(MPR)、容积再现(VR),显示其与胆总管下端的关系,并结合临床进行分析.结果 34例JDD,共发现乳头上型19例,乳头缘型10例,乳头水平外侧缘型1例,乳头下型4例.34例JDD合并胆总管结石7例,胆总管下端炎性狭窄11例,胆囊结石7例,急性胆囊炎4例,慢性胆囊炎17例,合并急性胰腺炎1例,慢性胰腺炎2例,合并肝内胆管小结石3例.结论 64层螺旋CT强大的后处理功能,不仅使JDD的检出率明显提高,更可显示其与十二指肠乳头的关系,可对临床胆系疾病的发病原因提供有益的帮助.%Objective To explore the value of 64-slice spiral CT in the diagnosis of juxtapapillary diverticulum of duodenum (JDD). Methods CT data in 34 cases of JDD confirmed by gastrointestinal radiography or endoscopic retrograde cholangiopancre-atography(ERCP) were retrospectively analysed. The relationship between the diverticulum and distal common bile duct was showed with multiplanar reconstruction!MPR) and volume rendering ( VR) by post-processing software. Results Among 34 cases, there were 19 cases of papillary-superior, 10 cases of nipple-margin, 1 case of the lateral opposite of the papillary-margin and 4 cases of papillary-inferior. In 34 cases ,there were 7 cases in combination with common bile duct stones, 11 cases of distal common bile duct inflammatory stricture,7 cases of cholelithiasis, 4 cases of acute cholecystitis, 17 cases of chronic cholecystitis, 1 case of acute pancreatitis, 2 cases of chronic pancreatitis and 3 cases of intrahepatic bile duct calculus correspondingly. Conclusion 64-slice spiral CT post-processing technology can not only improve the detecting rate of JDD significantly, but also can display the relationship

  7. 不同临床分期肾细胞癌的多层螺旋 CT 灌注研究%Study on value of 64 slice spiral CT perfusion in different clinical stages of renal cell carcinoma

    张颖颖; 董莹; 王义云


    Objective To evaluate the clinical value 64 slice spiral CT perfusion imaging in diagnosis for differ‐ent stages of renal cell carcinoma .Methods The clinical data of 41 patients with renal cell carcinoma from January 2011 to October 2013 were analyzed retrospectively .Using the pathological examination results as gold standard , blood flow perfusion after treatment ,blood volume(BV) ,peak enhancement (PEI) ,time to peak (TTP) ,mean transit time (MTT) and permeability surface (PS) were compared in differen stages ,evaluation index of CT in diagnosis for renal cell carcinoma staging were calculated .Results There were significant difference on perfusion ,BV ,PEI ,MTT , PS parameters between early and advanced renal cell carcinoma (P0 .05) .The sensitivity ,specificity ,misdiagnosis rate ,missed diagnosis rate and Youden index of renal CT perfusion imaging were 86 .36% ,89 .47% ,10 .53% ,13 .64% ,1 .758 and 0 .758 respetively .Conclusion There is high accuracy of 64 slice spiral CT perfusion imaging in diagnosis for different stages of renal cell carcinoma , which is worthy of application and promotion .%目的:探讨利用64排螺旋C T灌注成像技术对不同分期肾细胞癌进行诊断的临床价值及方法。方法回顾性分析莱芜市人民医院2011年1月至2013年10月收治的41例肾细胞癌患者的临床资料,以病理学检查结果作为临床分期的金标准,比较不同分期肾细胞癌的CT灌注成像经灌注软件包处理后的血流量(Perfusion),血容量(BV),峰值强化(PEI),达峰时间(TTP),平均通过时间(MTT),表面通透性(PS)指标的差异,同时计算CT诊断肾细胞癌分期的诊断学评价指标。结果早期肾细胞癌和晚期肾细胞癌的Perfusion、BV、PEI、M T T、PS参数比较,差异有统计学意义(P<0.05),而TTP参数比较差异无统计学意义(P>0.05)。采用CT 灌注成像技术诊断肾细胞癌分期的灵敏度为86.36

  8. 64排螺旋CT仿真结肠镜在结肠癌诊断中的应用%Clinical application of 64-slice spiral CT virtual colonoscopy in diagnosis of colonic carcinoma



    目的 探讨64排螺旋CT仿真结肠镜(CT virtual colonoscopy,CTVC)及其二维三维重建在结肠占位的CT表现及临床应用.方法 回顾分析52例行64排螺旋CT双体位结肠扫描的结肠癌病例,所有患者均进行结肠充气仰卧位及俯卧位增强扫描,其中20例增加了左或右侧位三期扫描,将MSCT扫描原始数据传送至ADW4.4工作站采用CT仿真结肠镜(CTVC)、多平面重建(MPR)、表面遮盖显示(SSD)、透明重建显示(Raysum)4种方法进行结肠重建处理,对病灶的形态、大小、密度、结肠壁受损的程度、范围以及结肠外情况、淋巴结转移情况进行综合分析,做出准确判断.结果 结肠、直肠癌52例,全部病例均经过手术及纤维结肠镜检查活检病理证实.结论 MSCT仿真结肠镜可显示结肠占位病变的形态、大小及肠壁、肠周侵犯情况,多体位扫描能使病变肠管扩张充分,更好地显示病灶的细节,提高病变检出的敏感性,为临床选择合理的治疗提供有价值的依据,是诊断结肠占位的一种有效检查方法.%Objective To investigate the CT manifestations and diagnostic value of 64 - slice spiral CT virtual colonoscopy (CTVC) and its 2D/3D - reslruction in colonic neoplasms. Methods 64 - slice spiral CT scan of colon was performed in 52 patients, Spiral CT enhancing scan was performed in both the supine and prone positions after appropriately distended by introduction of air and water, and triple - phase spiral CT enhanced scan were additionally performed in 20 of 52 cases, and the data of MSCT were transferred to ADW4.4 workstation for colon reconstruction image post processing including CT virtual colonoscopy (CTVC) , multiple planar reconstruction (MPR) , shaded surface display (SSD) and Raysum display. The MSCT findings of the shape, size and density of lesions, the injury extent and range of colonic wall and extracolon, and lymph node metastasis were analyzed and estimated. Results Totally 52

  9. 64排CT用于创伤性颅脑损伤诊断中的价值%Value of Applying 64-slice CT to Diagnosis of Traumatic Brain Injury



    Objective To research and analyze the value of applying 64-slice CT to diagnosis of traumatic brain injury. Methods 100 patients with traumatic brain injury were selected as main survey samples randomly. All patients received CT examination when they were admitted to the hospital. The patients with negative examination result received CT reexamination in 1 day. If the examination results were negative, the patients needed to receive CT examination for the third day. CT image features of 100 patients were analyzed carefully, and were divided into three types according to the actual characteristics of CT image. The condition of different injury classiifcations was analyzed. Results The sensitivity of the patients for the admission to hospital (30~180 minute), in one day and in 2~3 day was 69.00%, 73.00%and 100.00%. The light, medium and severe brain injury had different prognostic effect. The severer the injury, the higher disability rate and fatality rate, which had evident statistical signiifcance, P<0.05. Conclusion 64-slice CT achieves evident effect for diagnosing brain injury.%目的:研究分析64排CT用于创伤性颅脑损伤诊断中的价值。方法随机选取创伤性颅脑损伤患者100例作为主要的调查样本,在患者入院时均接受CT检查,对于检查结果为阴性的患者,在1天之内完成CT复查;若其检查结果还是阴性的患者,则需要在第2-3天之内第三天接受CT检查。对100例患者的CT影像特点进行缜密分析,严格按照CT影像的实际特点完成轻、中、重三型划分,对不同损伤分型影响预后的情况进行针对分析。结果刚刚入院时候(30~180分钟)、1天之内、2~3天内患者的灵敏度分别为69.00%、73.00%、100.00%。轻型、中型以及重型颅脑损伤存在不同的预后效果,即损伤越严重就会有越高的致残率以及致死率,具有明显的统计学意义,P<0.05。结论64排CT在诊断颅脑损伤优势的过程中可以取得非常明显的效果。

  10. Moyamoya Disease:Diagnostic Value of 64-slice Spiral CT Angiography%烟雾病64层螺旋CT血管成像的诊断价值

    李杨; 杨峰; 余河


    目的:探讨烟雾病64层螺旋CT血管成像(MSCTA)的表现,评价其临床诊断价值.方法:收集行64层螺旋CT平扫及血管成像检查并临床确诊的烟雾病患者27例,在ADW4.3工作站上对原始图像做二维及三维处理:容积再现(VR)、最大密度投影( MIP)、剪影后容积再现、多平面重组(MPR)及曲面重组(CPR),总结烟雾病的64层螺旋CT血管成像特点.结果:27例双侧颈内动脉远段、大脑前动脉及中动脉近端狭窄、闭塞20例,单侧大脑中动脉闭塞5例,双侧大脑前动脉并大脑中动脉狭窄、闭塞2例,5例双侧大脑后动脉代偿性增粗;3例合并基底动脉动脉瘤,2例合并大脑后动脉动脉瘤;27例均可见周围紊乱血管影,相应血管及其分支粗大、增多、迂曲延长.VR图像有利于显示狭窄闭塞段与周围骨性结构空间关系,但在显示评价脑底增生小血管和侧支血管方面不及MIP和MPR.结论:64层螺旋CT血管成像(MSCTA)可以清晰的显示烟雾病血管改变特点及周围侧支血管网,检查方法简单、快捷、无创伤,容积再现及剪影后容积再现可以直观显示病变周围空间结构关系,可作为诊断烟雾病的首选诊断方法.%Objective To explore the 64-slice spiral CT angiography (MSCTA) findings and clinical value for diagnosis of moyamoya disease. Methods Seventeen patients with moyamoya disease underwent routine CT scanning and MSCT angiography. All the patients were confirmed by DSA. The angiograms obtained were processed on the ADW4.3 workstation to perform volume rending(VR) , maximum intensity projection (MIP) and multiplanar Volume refomration (MPR) and curved planar reformatting( CPR). Results In all cases MSCTA showed the stenosis or obstruction of arteria carotis interna( ICA) or proximum of Wills circle, abnormal vessel network in brain basal part, including stenosis of bilateral ICA and anterior cerebral artery and middle cerebral artery(20 cases) ,one side middle

  11. Low dose scanning of 64 slice spiral CT in the diagnosis of pneumothorax in neonates%64层螺旋CT低剂量扫描在新生儿气胸诊断中的应用

    武军; 李彦杰


    目的:探讨64层螺旋CT低剂量扫描在新生儿气胸诊断中的应用,分析新生儿气胸的CT表现特点,以提高对新生儿气胸的认识及CT的诊断水平。方法用64层螺旋CT对23例临床可疑新生儿气胸进行低电压、低电流和增大螺距进行扫描,并对图像进行分析。结果患儿有不同类型的CT表现,如外侧肺气胸、内侧纵隔旁气胸、膈面附近及胸前部气胸等。结论新生儿肺气胸有一定的临床CT特征,对及时发现新生儿气胸,对临床诊断并及时处理有重要意义。%Objective Application of low dose of 64 row spiral CT scanning in the diagnosis of pneumothorax in neonatal pneumothorax, analysis CT charac-teristics, in order to improve the diagnostic level of understanding and CT on neonatal pneumothorax. Methods Twenty-three patients with clinically suspected of pneumothorax in neonates of low voltage, low current and increasing pitch were scanned by 64 slice spiral CT. And the image analysis. Results Patients with CT showed different types, such as lateral lung chest,medial mediastinum side pneumothorax, diaphrag-matic surface and near the front of pneumothorax. Conclusion Neonatal lung chest clinic and CT features, the timely detection of pneumothorax in neonates, for clinical diagnosis and timely treatment is meaningful.

  12. 肺癌特异血管征象的64层CT首过期灌注增强表达%Expressing the specific vessels signs in lung cancer by 64-slice spiral CT in first phase perfusion imaging *

    苏冠琴; 薄晓庆; 杨署; 孙国鹏; 柴军; 周苛; 高阿枚; 段呼兵; 董秀萍


    Objective To investigate the specific vessels signs in lung cancer by 64-slice spiral CT in first phase perfusion ima-ging so as to get more reasonable time about CT angiography .Methods Among the 47 cases ,there were 38 cases of central and 9 cases of peripheral primary lung cancer underwent 64-slice spiral CT in first phase perfusion imaging :one scan was obtained every 1 seconds during 8-38 seconds with 8 section × I without scanning interval after injection .Precontrast and postcontrast attenuation on every leisions was recorded ,to calculate the peak height(PH) and peak height time by time density curves TDC of pulmonary le-sions to aorta ,those reflect the the tumor feeding artery Imaging about lesions of lung cancer and inflammation .observed and calcu-lated the display rate and display time of lesions of lung cancer and inflammation .means of t test was used for statistics .Results a-bout the peak heights of in pulmonary artery and aorta phese ,statistically significant differences were found between inflammation and lung cancer(P0 .05) . about the peak heights time in aorta phase ,no statistically significant differences were found among three groups (P>0 .05) .The tumor vascularity were discoved in lesions in patients with lung cancer (44/47 cases ,93 .62% );The erosion narrow pulmonary ar-tery were discoved in central lung cancer (37/38 cases ,97 .37% ) ,in peripheral lung cancer(6/9 cases 66 .67% );no abnormal pulmo-nary artery were discoved only in 4 patients with lung cancer .Both tumor vascularity and abnormal pulmonary artery were most dis-plaied in 18-31s in CT angiography .Conclusion 64-slice spiral CT in first phase dynamic perfusion imaging can order completely show the specific vessels signs in lung cancer and reflect the tumor feeding artery Imaging of lung cancer .Analysising those benefi-ted to select reasonably the time of CT angiography and Improve the rate of lung cancer diagnosis .%目的分析64层C T首过期灌注增强对肺癌特

  13. Cirrhosis:CT grading with 64-slice spiral CT perfusion imaging%肝硬化CT分级的64层螺旋CT灌注成像分析

    陈勇; 郝凯; 尚英杰; 石俊英; 杨文魁


    目的 探讨肝硬化CT分级的临床价值.方法 对17例健康正常志愿者、54例肝硬化患者行CT灌注扫描,测量其血流量(BF)、血容量(BV)、肝动脉分数(HAF)、对比剂平均通过时间(MTT)、血管表面通透性(PS),对获得的相应灌注图进行肝硬化分级分析.结果 CT分级肝硬化程度越重,BF、BV越小,MTT、HAF、PS、肝动脉灌注量(HAP)越大.HAF、HAP在正常肝与轻、中、重度肝硬化之间有明显差异,HAF在中、重度肝硬化组明显增高.HAP在重度肝硬化组明显增高,PS、MTT在各组之间没有统计学意义.结论 通过肝脏的CT灌注研究,进一步证明了肝硬化CT分级确实与肝脏的灌注有一定关系,对临床肝硬化评估有一定价值.%Objective To evaluate the clinical value in grading of liver cirrhosis with 64-slice spiral CT perfusion imaging. Methods 17 healthy volunteers and 54 patients with liver cirrhosis underwent liver CT perfusion scanning. The blood flow(BF) , blood vol-ume(BV) , hepatic arterial fraction( HAF) , contrast agent mean transit time(MTT) and vascular permeability surface) PS) were measured on CT perfusion maps. Results CT perfusion imaging showed that the serious of cirrhosis,the lower of perfusion values of BF and BV,the higher of MTT,HAF,PS and hepatic arterial perfusionf HAP). There were significant differences between the normal liver and mild,moderate and severe cirrhosis in HAF and HAP,and HAF in moderate and severe cirrhosis of the liver was significantly increased. HAP in severe liver cirrhosis was significantly higher, PS, MTT between groups was not statistically significant. Conclusion By liver CT perfusion imaging study shows that the CT grading of cirrhosis is of certain relativity with liver perfusion, which is of significant value in evaluating cirrhosis clinically.

  14. Comparative Study in the Diagnosis of Intracranial Aneurysms with 64 Slice CTA-and 3D DSA%64层CTA-MIP、CTA-VR与3D-DSA对颅内动脉瘤诊断价值的对比研究



    目的 对比评价64层螺旋CT最大密度投影(CTA-MIP),CTA容积再现(CTA-VR)与三维数字血管造影(3D-DSA)对颅内动脉瘤(CA)的诊断价值.资料与方法 回顾性分析32例经手术及DSA确诊的CA 64层CT血管成像资料,并与DSA进行对照.结果 32例共40个动脉瘤,CTA-MIP发现35个动脉瘤,CTA-VR发现37个动脉瘤,3D-DSA发现39个动脉瘤.40个动脉瘤中11个位于后交通动脉,16个位于大脑中动脉,4个位于基底动脉,1个位于椎动脉,2个位于大脑前动脉,3个位于大脑后动脉,3个位于颈内动脉.3 D-DSA与CTA比较,差异无统计学意义.结论 在CA影像学诊断上,CTA-MIP、CTA-VR和3D-DSA各有优势,CTA可作为外科治疗或介入治疗的筛选方法.%Objective To evaluate the role of 64 slice computed tomography angiography maximum intensity projection (CTA,MIP) , computed tomography angiography volume rendering (CTA,VR) and 3 dimensional digital subtraction angiogtaphy(3D-DSA) ) in the diagnosis of intracranial aneurysms. Materials and Methods The CT and DSA imaging findings of 32 patients with aneurysms were retrospectively analyzed and compared. Results 40 aneurysms in 32 patients were found by DSA and/or operation. 35 aneurysms were found by CTA MIP. 37 aneurysms were found by CTA VR. 39 aneurysms were found by DSA. 11 aneurysms were at posterior communicating artery, 16 aneurysms at middle cerebral artery, 4 aneurysms at basilar artery, 1 aneurysms at vertebary artery, 2 aneurysms at anterior cerebral artery, 3 aneurysms at posterior cerebral artery, 3 aneurysms at internal carotid artery. There was no significant difference in detecting aneurysms between CTA and 3D DSA. Conclusion CTA MIP, CTA VR and 3D-DSA examination have their own advantage in diagnosis of intracranial aneurysms. CTA can be used as the method in screening intracranial aneurysms for surgery and interventional therapy.


    曾勇; 吴垦; 黎学刚


    [目的]进行64层螺旋CT灌注成像研究,探讨该技术在乳腺疾病诊断中的应用前景.[方法]选择于2008年5月~2009年5月期间临床检查或钼靶检查怀疑有乳腺疾病的61例女性患者行CT灌注扫描.按照病理将其分为3组:增生病组(n= 14)、纤维腺瘤组(n=19)和乳腺癌组(n=20),并将所有患者对侧乳腺定为正常组(n=61).进行灌注序列body perfusion扫描及Perfusion 3体部灌注软件处理,计算感兴趣区的血流动力学参数血流量(BF)、平均通过时间、血容量(BV)(MTT)和表面通透性(PS),统计分析不同组间的测量值.[结果]与乳腺癌组比较,正常组BF、BV及PS的差异均有统计学意义(P<0.05),MTT的差异无统计学意义(P>0.05);正常乳腺组与纤维腺瘤组、增生病组比较,BF及BV的差异均有统计学意义(P<0.05),MTT及PS的差异均无统计学意义(P>0.05);乳腺癌组与纤维腺瘤组比较,其BF、PS的差异有统计学意义(P<0.05),BV及MTT的差异无统计学意义(P>0.05);乳腺癌组与增生病组比较,其BF、BV及PS的差异均有统计学意义(P<0.05),MTT的差异无统计学意义(P>0.05);增生病组与纤维腺瘤组比较,其BF、BV、MTT及PS的差异均无统计学意义(P>0.05).正常组与乳腺癌组分别呈低灌注、高灌注状态,纤维腺瘤组及增生病组均呈较高灌注状态.[结论]64层螺旋CT作为先进的影像检查技术,其灌注成像能从血流动力学和影像学角度为各类乳腺疾病的进行较为准确的诊断.%[Objective] To study and evaluate multi-slice spiral CT perfusion imaging in the diagnosis of breast diseases the effect and value. [Methods] 61 patients through clinical examination or mammography of women with suspected breast disease patients with 64-slice spiral CT perfusion imaging. The pathology types were divided into three groups: hyperplasia group (n = 14), fibroadenoma group (n - 19) and breast cancer group (n = 20), and conlralaterai

  16. 64排螺旋CT多种后处理技术在肋骨骨折诊断中的应用%Application of Various Post Processing Techniques of 64 Slice Spiral CT in the Diagnosis of Rib Fractures



    目的:探讨64排螺旋CT多种后处理技术对肋骨骨折的诊断价值。方法以本院2014年2月-2016年2月就诊的疑似肋骨骨折75例胸部外伤患者为研究对象,均行X线平片、多层螺旋CT轴位、容积再现(VR)、多平面重建(MPR)等后处理技术检查,比较不同影像学方法对肋骨骨折、骨折数量检出情况。结果临床、影像学检查及复查确诊肋骨骨折165处,CT轴位、CT后处理技术对肋骨骨折例数检出率分别为96.00%、98.67%,较X线平片的80.00%差异有统计学意义(P<0.05)。CT后处理技术对肋骨骨折数量检出率为99.39%,较X线平片、CT轴位的71.52%、78.79%差异有统计学意义(P<0.05)。漏诊情况:X线平片漏诊41处,其中以肋软骨附近漏诊最多,占58.54%;CT轴位漏诊24处,其中肋软骨附近、腋段肋骨漏诊各5处;CT后处理技术未漏诊,可疑骨折数1处。结论64排螺旋CT后处理技术对肋骨骨折、骨折数量检出率高,漏诊率低,能有效弥补X线平片、CT轴位不足。%Objective To investigate the value of various post processing techniques of 64 slice spiral CT in the diagnosis of rib fractures. Methods 75 cases of patients with thoracic trauma and suspected rib fractures who were treated in our hospital between February 2014 and February 2016 were selected as study subjects. All of them were examined by X-ray plain film, multi-slice spiral axial CT, volume rendering (VR), multi planar reconstruction (MPR) and other post-processing techniques. The situation of different imaging methods in the detection of rib fractures and number of fractures was compared. Results 165 rib fractures were diagnosed by clinical, imaging examination and reexamination. The detection rates of axial CT and CT post processing techniques in number of cases with rib fractures were 96.00%and 98.67%, respectively. Compared with X-ray plain film (80.00%), the difference was significant (P<0.05). The

  17. MSCT血管成像对肝移植受体术前血管结构的评价%The evalution of the vascular structure of preoperative liver transplantation recipients using 64-slice spiral CT angiography

    李妙玲; 刘雯雁; 袁会军; 强永乾; 孙兴旺; 赵婷婷


    Objective To evaluate the clinical significance of 64-slice spiral CT angiography for vascular structures of preoperative liver transplantation recipients. Methods Tri-phase enhanced CT scan were performed in 32 cases, All cases were post-processing with maximum intensity projection(MIP) , volume rendering(VR) ,and all reformation images with axial images were analyzed. Results In all 32 cases, 1 case with absence of celiac artery, 3 cases with stenosis of celiac artery caused by plaque, 12 cases with dilated splenic artery, 2 cases with splenic artery aneurysm, 7 cases with variation of hepatic artery. 3 cases with extrahepatic portal vein thrombosis, 2 cases with intrahepatic portal vein thrombosis, 1 case with thrombosis in superior mesenteric vein, 1 case with muti-ple thrombosis in portal vein and superior mesenteric vein. In all 32 cases, 25 cases with good images of hepatic vein, 14 cases with standard hepatic vein, 11 cases with common drainage of the middle and the left hepatic vein into the inferior vena cava, and 1 case with inferior hepatic vein respectively,? Cases with poor images. In all 32 cases,30 cases with normal inferior vena cava, 1 case with embolism in inferior vena cava and 1 case with embolism near the right atrium. In all 32 cases, 24 cases received liver transplantation successfully, the other 8 cases had the contraindications of liver transplantation and gave up operation,of 8 cases, 3 cases with total diameter of cancer nodules were more than 8 cm,l case with mutiple thrombosis, 4 cases with extrohepatic metastasis(including 1 case with total diameter of cancer nodules were more than 8 cm) , 1 case with Michels MD had narrowing hepatic artery and the diameter was less than 3 mm separately. Conclusion 64-slice spiral CT tri-phase angiography could overall evaluate structural changes of the hepatic vessels and choose the cases suitable for surgery,it has an important value for surgery program.%目的 探讨64排螺旋CT血管成像对肝

  18. 64层CT脑灌注联合CTA在早期缺血性脑血管病中的应用%Application of perfusion and CTA by 64 slice CT in early ischemia cerebral infarction

    李培秀; 都日娜; 丁俊丽; 张强


    目的 探讨64层螺旋CT脑灌注加CT血管成像技术在早期脑梗死的应用价值.方法 分析总结108例发病在6h内临床可疑脑梗死,其中105例进行CT平扫、CT脑灌注和CTA,部分复查CTP的住院患者资料,并对影像资料做统计学分析.结果 CT平扫7例脑实质密度轻微减低、脑沟变浅(6.6%),CT脑灌注83例显示与临床症状对应区域血流灌注异常(79.1%),与对侧比较CBF下降、CBV下降或正常、TTP延长.22例CT灌注未见异常(20.9%).CT血管成像显示53支动脉(39例)有不同密度斑块及管腔狭窄,3例检查未成功.结论 CT脑灌注加CTA成像技术可以快速、准确确定缺血半暗带及病变血管,对早期缺血性脑血管脑的诊断和指导治疗有重要的临床应用价值.%Objective To discuss the application of cerebral perfusion and CT blood vessel imaging technique by 64-slice CT in diagnosis of cerebral infarction in its early phase. Methods To analyze and summarize the data of 108 patients who were suspected of the ischemic infarction in 6 hours. 105 among the patients were examined by CT scanning, CT perfusion and CTA. Some of those patients needed the examination by CTP again. All data were analyzed statistically. Results CT scanning showed a slight reduction in the density of brain parenchyma in 7 cases, with brain shallow groove(6. 6%) and CT perfusion showed blood perfusion abnormal corresponding to clinical symptom region in 83 cases (79. 1%). Compared with the contra-lateral, CBF were decreased and CBV were decreased or normal while TTP was extend. 22 cases of CT perfusion showed regular!20. 9%). CT blood vessel imaging showed that 53 arteries of 39 patients had spots and the pipes were narrow. 3 cases were not successful. Conclusion Cerebral perfusion and CTA imaging technique by CT can quickly and exactly definite ischemia and pathology blood vessel, which is of great clinical importance for diagnosing and curing brain ischemia in its early phase.

  19. 64排螺旋CT对先天性主动脉缩窄诊断的临床应用价值%Clinical Application of 64-slice Spiral CT Angiography in Diagnosing the Congenital Coarctation of Aorta

    王小红; 亓波


    Objective To evaluate the clinical diagnostic valie of 64-slice spiral CT angiography (CTA )in coarctation of aorta (CoA).M ethods 154 caseswith coarciation of the aorta(47 women and 107 men;mean age3 .3 years;age range 20 days-60 years) were diagnosed by by 64-slfce spiral CT angiDgraphy (CTA ) and translhoracic echocardiography (TTE ) ,and 77 of than were treated by operation .Results In the operative 77 cases ,17 m issed by TTE and no case missed by CTA .The definite diagnosis rate of TTE was 77 .9% ,and the definite diagnosis rate of CTA was 100% .Among 154 cases,44 cases (28 .6% ) were staple aortic coarctation , 95 cases(61.7% )were pediatric pcmpfex portic coarctation and 15 cases(9 .7% ) were atypicalpomplex portic coarctation .therewere significant differences bete een year of three types CoA ( P<0 .001) .The m ean stenotic ratio (the diam eterof the ooarctatbn to thatofthe proxinalnomalsegnentof the aortic ooarctation )R = 0 .29+0 .13 .Conclusion MDCT examhation is able to clearly display type,scope,extent and can plicated m alform ations ,can provide in portent infem ation for the diagnosis and teatn ent of aortic ooaictetian.%目的 评价64排螺旋CT(MDCT)在主动脉缩窄临床诊断中的价值.方法 154例主动脉缩窄患者,男性107例,女性47例,年龄20天-60岁,平均3.3岁,均采用64排螺旋CT血管成像扫描和经胸心脏超声检查.结果 77例经手术证实CoA病例中,超声心动图检查55例明确诊断,5例诊断可疑,17例漏诊,准确率为77.9%(60/77),MDCT均明确诊断,准确率为100%(77/77).154例主动脉缩窄患者中,单纯型44例(28.6%),复杂婴儿型95例(61.7%),复杂不典型型15例(9.7%);其中局限性缩窄91例(59.1%),管性缩窄63例(40.9%),3种类型的CoA在年龄分布上存在着显著性差异(K-W统计值为22.9,P<0.001).MDCT测量最窄处内径与主肺动脉水平升主动脉内径比值R为0.29±0.13.结论 CTA能够全面显示主动脉缩窄的类型、范围程度及伴随畸形,能

  20. Bent Si monochromator—multi-detector neutron diffractometer installed at B4 super-mirror thermal guide tube in KUR

    Achiwa, N.; Kawano, S.; Hino, M.; Mikula, P.; Ono, M.; Fukunaga, T.


    A new multi-detector neutron diffractometer has been installed at B4 thermal supermirror neutron guide in KUR, using a new bent Si monochromator developed by Mikula et al. and Ono et al.. Here we report resolutions of powder diffraction patterns by the multi-detector neutron diffractometer, which mainly depend on a radius of sample. Bragg diffraction optics by bent perfect crystal shows improvement of resolution without loss of luminosity and the multi- detector on the same 2 θ arm can gain the intensity without loosing resolution.

  1. Study of statistical properties of hybrid statistic in coherent multi-detector CBC Search

    Haris, K


    In this article, we revisit the problem of coherent multi-detector search of gravitational wave from compact binary coalescence with Neutron stars and Black Holes using advanced interferometers like LIGO-Virgo. Based on the loss of optimal multi-detector signal-to-noise ratio (SNR), we construct a hybrid statistic as a best of maximum-likelihood-ratio(MLR) statistic tuned for face-on and face-off binaries. The statistical properties of the hybrid statistic is studied. The performance of this hybrid statistic is compared with that of the coherent MLR statistic for generic inclination angles. Owing to the single synthetic data stream, the hybrid statistic gives low false alarms compared to the multi-detector MLR statistic and small fractional loss in the optimum SNR for a large range of binary inclinations. We have demonstrated that for a LIGO-Virgo network and binary inclination, \\epsilon 110 deg., the hybrid statistic captures more than 98% of network optimum matched filter SNR with low false alarm rate. The...

  2. Noninvasive coronary angiography using 64-slice spiral computed tomography in an unselected patient collective: Effect of heart rate, heart rate variability and coronary calcifications on image quality and diagnostic accuracy

    Brodoefel, H. [Department of Diagnostic Radiology, Eberhard-Karls-University, Hoppe-Seyler-Str. 3, 72076 Tuebingen (Germany)], E-mail:; Reimann, A. [Department of Diagnostic Radiology, Eberhard-Karls-University, Hoppe-Seyler-Str. 3, 72076 Tuebingen (Germany); Burgstahler, C. [Department of Cardiology, Eberhard-Karls-University, Otfried-Mueller-Str. 10, 72076 Tuebingen (Germany); Schumacher, F. [Department of Diagnostic Radiology, Eberhard-Karls-University, Hoppe-Seyler-Str. 3, 72076 Tuebingen (Germany); Herberts, T. [Department of Medical Biometry, Westbahnhofstr. 55, 72070 Tuebingen (Germany); Tsiflikas, I. [Department of Diagnostic Radiology, Eberhard-Karls-University, Hoppe-Seyler-Str. 3, 72076 Tuebingen (Germany); Schroeder, S. [Department of Cardiology, Eberhard-Karls-University, Otfried-Mueller-Str. 10, 72076 Tuebingen (Germany); Claussen, C.D.; Kopp, A.F.; Heuschmid, M. [Department of Diagnostic Radiology, Eberhard-Karls-University, Hoppe-Seyler-Str. 3, 72076 Tuebingen (Germany)


    Objective: The aim of this study was to assess the impact of heart rate, heart rate variability and calcification on image quality and diagnostic accuracy in an unselected patient collective. Subjects and methods: One hundred and two consecutive patients with known or suspected coronary artery disease underwent both 64-MSCT and invasive coronary angiography. Image quality (IQ) was assessed by independent observers using a 4-point scale from excellent (1) to non-diagnostic (4). Accuracy of MSCT regarding detection or exclusion of significant stenosis (>50%) was evaluated on a per segment basis in a modified AHA 13-segment model. Effects of heart rate, heart rate variability, calcification and body mass index (BMI) on IQ and accuracy were evaluated by multivariate regression. IQ and accuracy were further analysed in subgroups of significant predictor variables and simple regression performed to calculate thresholds for adequate IQ. Results: Mean heart rate was 68.2 {+-} 13.3 bpm, mean heart rate variability 11.5 {+-} 16.0 beats per CT-examination (bpct) and median Agatston score 226.5. Average IQ score was 2 {+-} 0.6 whilst diagnostic quality was obtained in 89% of segments. Overall sensitivity, specificity, PPV or NPV was 91.2%, 99.2%, 95.3% or 98.3%. According to multivariate regression, overall IQ was significantly related to heart rate and calcification (P = 0.0038; P < 0.0001). The effect of heart rate variability was limited to IQ of RCA segments (P = 0.018); BMI was not related to IQ (P = 0.52). Calcification was the only predictor variable with significant effect on the number of non-diagnostic segments (P < 0.0001). In a multivariate regression, calcification was also the single factor with impact on diagnostic accuracy (P = 0.0049). Conclusion: Whilst heart rate, heart rate variability and calcification all show an inverse correlation to IQ, severe calcium burden remains the single factor with translation of such effect into decrease of diagnostic accuracy.

  3. 64层螺旋CT腹部扫描参数优化的个体化选择%Optimization of individualized abdominal scan protocol with 64-slice CT scanner

    胡敏霞; 赵心明; 宋俊峰; 周纯武


    目的 探讨64层螺旋CT腹部扫描参数优化的个体化选择.方法 回顾性分析2010年9月至11月期间,3个月内因临床诊断或治疗需要行2次腹部CT平扫检查的连续患者100例资料.首次检查采用管电流274有效mAs(eff.mAs),第2次检查采用207 eff.mAs,分析评价2次检查的图像质量.记录受检者身高、体质量、体质量指数(BMI)、上腹部最大横径、上腹部前后径、上腹部平均最大径.3名阅片者对腹主动脉、门静脉主干、肝脏、脾脏、胆囊、胰腺、肾皮质、肾髓质等8个主要器官进行图像主观噪声评价,对肝门、胰腺、肾上极3个主要层面进行诊断接受率评价.采用散点图及Pearson相关分析显示各指标与腹主动脉噪声值(SD值)的线性关系,通过多因素线性回归分析评价各指标与腹主动脉SD值的相关性,利用最相关的指标指导腹部CT个性化参数扫描.结果 100例受试者体质量为(64.3±11.0) kg,BMI为(23.7±3.3)kg/m2,上腹最大横径为(29.8±2.3)cm,上腹前后径为(23.1±2.9)cm,上腹平均最大径为(26.5±2.5)cm,分别与主动脉SD值(11.7±3.0)呈中度或高度相关(r值分别为0.744、0.689、0.813、0.781、0.789,P值均<0.01),身高为(164.6±7.5)cm,与主动脉SD值基本不相关(r=0.292,P<0.01).上腹部最大横径与肝门层面腹主动脉SD值最相关且两者的线性关系具有统计学意义(Beta=0.487,P<0.01).上腹最大横径在27~32 cm范围内其肝门层面诊断接受率评价与上腹最大横径<27 cm或者>32 cm差异具有统计学意义(P值均<0.05).结论 管电流207 eff.mAs适用于上腹最大横径在27~32 cm范围内的受检者.%Objective To explore an individualized abdominal scan protocol with a 64-slice CT scanner.Methods From Sep.2010 to Nov.2010,one hundred consecutive patients,who underwent twice non-contrast-enhanced abdominal CT scans within 3 months,were enrolled in this study.For each patient,the tube current of 274 eff

  4. [Computed tomography of the heart

    Kristensen, T.S.; Kofoed, K.F.; der, Recke P. von;


    Noninvasive evaluation of the coronary arteries by multi-detector row computed tomography is a promising new alternative to conventional invasive coronary angiography. This article describes the technical background, methods, limitations and clinical applications and reviews current literature...

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

    Yahaba, Misuzu, E-mail:; Kawata, Naoko, E-mail:; Iesato, Ken, E-mail:; Matsuura, Yukiko, E-mail:; Sugiura, Toshihiko, E-mail:; Kasai, Hajime, E-mail:; Sakurai, Yoriko, E-mail:; Terada, Jiro, E-mail:; Sakao, Seiichiro, E-mail:; Tada, Yuji, E-mail:; Tanabe, Nobuhiro, E-mail:; Tatsumi, Koichiro, E-mail:


    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.

  6. Double Chooz: optimizing the sensitivity to {theta}{sub 13} with a multi-detector setup

    Novella, P. [CIEMAT, Av. Complutense 22, 28040 Madrid (Spain)


    The best upper limit to the neutrino mixing angle {theta}{sub 13} is set by the CHOOZ experiment. The eventual measurement of {theta}{sub 13} in reactor neutrino experiments relies on a reduction of the CHOOZ systematics of about 1 order of magnitude, along with a major increase of the luminosity. Provided that enough statistics are achieved, fighting the systematics becomes the key towards {theta}{sub 13}. The Double Chooz experiment engages this fight with a multi-detector set up.

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

    Vande Berg, Bruno; Malghem, Jacques; Maldague, Baudouin; Lecouvet, Frederic


    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.

  8. Control electronics for a multi-laser/multi-detector scanning system

    Kennedy, W.


    The Mars Rover Laser Scanning system uses a precision laser pointing mechanism, a photodetector array, and the concept of triangulation to perform three dimensional scene analysis. The system is used for real time terrain sensing and vision. The Multi-Laser/Multi-Detector laser scanning system is controlled by a digital device called the ML/MD controller. A next generation laser scanning system, based on the Level 2 controller, is microprocessor based. The new controller capabilities far exceed those of the ML/MD device. The first draft circuit details and general software structure are presented.

  9. Pitfalls in detection of acute gastrointestinal bleeding with multi-detector row helical CT.

    Stuber, T; Hoffmann, M H K; Stuber, G; Klass, O; Feuerlein, S; Aschoff, A J


    Contrast-enhanced multi-detector row helical CT angiography is establishing itself as an accurate, rapid, and non-invasive diagnostic modality in patients with acute gastrointestinal bleeding. On arterial phase MDCT images ongoing hemorrhage can be revealed as an area of active extravasation of contrast material within the bowel lumen. This pictorial essay gives a short overview of current diagnostic modalities in assessing acute GI tract bleeding, typical MDCT findings, and depicts potential pitfalls in the detection of acute GI bleeding with MDCT.

  10. Novel wearable and wireless ring-type pulse oximeter with multi-detectors.

    Huang, Cheng-Yang; Chan, Ming-Che; Chen, Chien-Yue; Lin, Bor-Shyh


    The pulse oximeter is a popular instrument to monitor the arterial oxygen saturation (SPO2). Although a fingertip-type pulse oximeter is the mainstream one on the market at present, it is still inconvenient for long-term monitoring, in particular, with respect to motion. Therefore, the development of a wearable pulse oximeter, such as a finger base-type pulse oximeter, can effectively solve the above issue. However, the tissue structure of the finger base is complex, and there is lack of detailed information on the effect of the light source and detector placement on measuring SPO2. In this study, the practicability of a ring-type pulse oximeter with a multi-detector was investigated by optical human tissue simulation. The optimal design of a ring-type pulse oximeter that can provide the best efficiency of measuring SPO2 was discussed. The efficiency of ring-type pulse oximeters with a single detector and a multi-detector was also discussed. Finally, a wearable and wireless ring-type pulse oximeter was also implemented to validate the simulation results and was compared with the commercial fingertip-type pulse oximeter.

  11. Novel Wearable and Wireless Ring-Type Pulse Oximeter with Multi-Detectors

    Cheng-Yang Huang


    Full Text Available The pulse oximeter is a popular instrument to monitor the arterial oxygen saturation (SPO2. Although a fingertip-type pulse oximeter is the mainstream one on the market at present, it is still inconvenient for long-term monitoring, in particular, with respect to motion. Therefore, the development of a wearable pulse oximeter, such as a finger base-type pulse oximeter, can effectively solve the above issue. However, the tissue structure of the finger base is complex, and there is lack of detailed information on the effect of the light source and detector placement on measuring SPO2. In this study, the practicability of a ring-type pulse oximeter with a multi-detector was investigated by optical human tissue simulation. The optimal design of a ring-type pulse oximeter that can provide the best efficiency of measuring SPO2 was discussed. The efficiency of ring-type pulse oximeters with a single detector and a multi-detector was also discussed. Finally, a wearable and wireless ring-type pulse oximeter was also implemented to validate the simulation results and was compared with the commercial fingertip-type pulse oximeter.

  12. The Analysis of Blood Flow Dynamics About 64-slice Spiral CT Perfusion Imaging for Primary Liver Cancer%原发性肝癌患者64层螺旋CT灌注成像血流动力学分析



    目的:探讨原发性肝癌患者64层螺旋CT灌注成像血流动力学的表现。方法收集2012年8月~2013年7月来我院就诊的确诊为原发性肝癌的患者46例并将其作为观察组,选取2012年8月~2013年7月来我院进行健康体检的健康对象46例并将其作为对照组,血液流动力学表现采用64层螺旋CT灌注成像观察,检测并比较两组患者肝动脉灌注量、肝门静脉灌注量、总肝灌注量、肝动脉灌注指数。结果观察组肝动脉灌注量、肝动脉灌注指数高于对照组,肝门静脉灌注量、总肝灌注量低于对照组,两组差异有统计学意义(P<0.05)。结论原发性肝癌患者采用64层螺旋CT灌注成像诊断血液流动力学表现较为显著,具有较高的诊断价值。%Objective To Einvestigate the blood flow dynamics about 64-slice spiral CT perfusion imaging for primary liver cancer. Methods 46 patients with primary liver cancer diagnosed in our hospital were collected from August 2012 to July 2013 and taken as the observation group, 46 cases of health object for physical examination in our hospital were selected at the same time as the control group, observed the blood lfow dynamics performance used by 64-slice spiral CT perfusion imaging, the two groups were measured and compared about hepatic arterial perfusion, hepatic portal vein perfusion, total liver perfusion, hepatic perfusion index. Results Hepatic arterial perfusion, hepatic perfusion index of observation group were higher, the hepatic portal vein perfusion, total hepatic perfusion were lower than the control group, the difference was statistically significant (P<0.05). Conclusions Primary liver cancer patients use 64-slice spiral CT perfusion imaging in the diagnosis of blood lfow dynamics performance is more signiifcant, with high diagnostic value.

  13. 起搏器置入患者640层与64层CT冠状动脉造影图像质量和伪影的比较%Comparative Study of Image Quality and the Artifact of Coronary Angiography between 640-slice and 64-slice CT in the Patients with Pacemaker

    王振; 丁忠祥; 王博业; 狄幸波; 袁建华; 徐健; 陈军法; 钟建国


    Objective To compare the image quality and artifact between 640 - slice and 64 - slice CT coronary angiography in the patients with pacemaker, and to evaluate the success rate and applicability of CT coronary angiography. Methods Twenty - four patients with pacemaker were divided into two groups. Group A ( 16 patient) underwent 640 - slice CT coronary angiography, and Group B ( 8 patient) underwent 64 - slice CT coronary angiography. Image quality and artifact of the fifteen coronary segments were assessed by two blinded observers. Radiation dosage and patient's common information were recorded. Data sets were analyzed using parametric and nonpara-metric statistical tests with the SPSS 13.0 software. Results There was no significant difference in body weight and body height between the two groups. Radiation exposure was significantly higher with 64 - slice CT than with 640 - slice CT ( 13. 8 ± 1. 53 mSv vs 9. 14 ± S.6S mSv; P<0.001) despite significantly higher heart rates in the 640 - slice CT group [61 ±4bpm ( beats per minute) vs 71 ±6bpm; P <0. 001 ] . The rate of available diagnostic images was greater for images obtained with 640 - slice CT than for images obtained with 64 -slice CT(99.06% vs93.27% ; P<0.05). Artifacts were the cause of coronary arteries that cannot be evaluated for coronary MSCT angiography. They were blurring artifact, stairstep artifact, streak artifact, missing data. There were significant differences in these artifacts between the two groups( continuity corrected^2 = 5.009,/* <0.05). Artifacts of group A were mild (94.3% ) , and artifacts of group B were severe artifacts (31.8% ). Conclusion 640 - slice and 64 - slice CT coronary angiography have excellent image quality in patients with pacemaker. 640 - slice CT provides significantly better diagnostic image quality and artifacts of little influence than those of 64 - slice CT, and it had more success rate and applicability of CT coronary angiography.%目的

  14. Performance comparison of multi-detector detection statistics in targeted compact binary coalescence GW search

    Haris, K


    Global network of advanced Interferometric gravitational wave (GW) detectors are expected to be on-line soon. Coherent observation of GW from a distant compact binary coalescence (CBC) with a network of interferometers located in different continents give crucial information about the source such as source location and polarization information. In this paper we compare different multi-detector network detection statistics for CBC search. In maximum likelihood ratio (MLR) based detection approaches, the likelihood ratio is optimized to obtain the best model parameters and the best likelihood ratio value is used as statistic to make decision on the presence of signal. However, an alternative Bayesian approach involves marginalization of the likelihood ratio over the parameters to obtain the average likelihood ratio. We obtain an analytical expression for the Bayesian statistic using the two effective synthetic data streams for targeted search of non-spinning compact binary systems with an uninformative prior on...

  15. Prognostic value of multi-detector computed tomography in asymptomatic aortic valve stenosis

    Larsen, Linnea Hornbech; Kofoed, Klaus Fuglsang; Carstensen, Helle Gervig;


    was defined as indication for aortic valve replacement (AVR) determined by the treating physician or sudden cardiac death. RESULTS: The mean age was 72 (8) years, 27% were women, mean AVA by TTE was 1.01 (0.30) cm(2). Median follow up time was 27 (IQR 19-44) months. Forty seven patients (41%) developed...... indication for AVR. No patients suffered a sudden cardiac death. AVA and aortic valve calcification were significant univariable predictors of AVR when measured by both TTE and MDCT, whereas left ventricular mass was only significant measured by MDCT. Significant coronary artery disease by MDCT tended...... to predict future indication for AVR, but this did not reach statistical significance (HR: 1.79 (95% CI 0.96-3.44), p=0.08). CONCLUSION: MDCT derived AVA can be of use as an alternative to TTE derived AVA in patients with asymptomatic AS to predict future clinical indication for AVR....

  16. Multi-detector computed tomography (MDCT findings of chemotherapy induced hepatic chan

    Sieza Samir Abd-Allah


    Results: Forty patients (32 females and 8 males had hepatic changes due to effect of chemotherapy. The most common CT finding was fatty liver. Hepatic fatty changes were detected in 36/40 patients. These fatty changes were diffuse, focal fatty and diffuse with fatty spare area. Four patients had capsular retraction: 1 patient with HD and 3 patients with metastatic cancer breast. Veno-occlusive disease and biliary sclerosis were not detected.

  17. Value of 64-slice spiral CT perfusion imaging in estimating the efficacy of transcatheter arterial chemoembolization for the treatment of hepatocellular carcinoma%64排螺旋CT灌注成像在肝细胞癌介入治疗前后的评估价值


    Objective To discuss the clinical value of 64-slice spiral CT perfusion imaging(CTPI) in estimating the efficacy of transcatheter arterial chemoembolization ( TACE ) for hepatocellular carcinoma (HCC).Methods Using 64-slice spiral CT(GE LightSpeed VCT XT),all CT plain scan and perfusion scan were performed in 30 patients with HCC 1-3 days before and 30-40 days after TACE .Using deconvolution through Infusion Software analysis , hepatic blood flow ( BF ) , blood volume ( BV ) , the mean transit time ( MTT) , hepatic arterial fraction ( HAF ) , permeability surface ( PS ) were caculated to evaluate HCC embolization hemodynamic status .Results After TACE,the tumor was totally filled with lipiodol in 12 cases and partially filled with lipiodol in 18 cases.BF,BV,MTT,HAF and PS perfusion maps showed that lack of blood perfusion was found in lipiodol-filling areas, but sparsely or insufficiently lipiodol-filled areas were hyperperfusion.BF,BV,HAF and PS of HCC after TACE were lower than those of HCC before TACE (P0.05 ) .Conclusions 64-slice spiral CT liver perfusion imaging can be used to monitor the blood supply changes in non -iodized oil deposits area non-invasively ,dynamically ,quantitatively ,which was very important in judging the tumor tissue survival and played an important role in response evaluation of HCC interventional therapy and guiding the follow -up treatment.%目的:探讨64排螺旋CT灌注成像(CTPI)在原发性肝细胞癌(HCC)肝动脉插管化疗栓塞( TACE )术前、后疗效的评估价值。方法选取30例HCC 患者,于TACE术前1~3 d、术后30~40 d应用GE LightSpeed VCT XT(64排128层螺旋CT)分别行全肝常规平扫及灌注扫描,运用灌注软件进行分析,计算肝血流量(BF)、血容量(BV)、平均通过时间(MTT)、肝动脉灌注指数(HAF)、毛细血管通透性( PS )等,统计分析相关参数,以评价 HCC 介入治疗前后的血流动力学状态。结果 TACE

  18. The Correlation Analysis of 64-slice Coronary CT Angiography: Effect of Average Heart rate, Heart Rate Range and Heart Rate Variability on Image Quality%平均心率、心率波动和心率变异性对64层螺旋CT冠脉成像质量的相关性分析

    朱玉春; 王建良; 吴志娟; 沈纪芳; 王伟伟; 刘丽华; 朱晟超; 张臻


    Objective The purpose of this study was to evaluate the effect of average heart rate,heart rate range and heart rate variability on the image quality with 64-slice spiral CT coronary angiography. Methods 200 patients underwent 64-slice coronary CT angiogra-phy ,which were suspected coronary artery diseases. Image quality was performed using five score method. The detailed analysis was performed to evaluate the relationship of average heart rate,heart rate range and heart rate variability on the image quality. Results 600 coronary angiography were analyzed in 200 patients. The average heart rate was 69.20 ± 8.80 beat per minute(heart rate rang , l~38bmp), with a variability of 8.50 ±6.75%. Image quality was sufficient for diagnosis for 94.3%(566/600)of arterial segment at the best reconstruction interval. A significan correlation (P<0.05) between overall image quality was found for average heart rate, heart rate range and heart rate variability. The lower average heart rate,the less heart rate range and variability, the better coronary image quality. Conclusion Coronary angiography with 64-slice spiral CT can provides best diagnostic image quality within a wide range of heart rates, and reducing average heart rate and heart rate variability in patients is beneficial in improving image quality.%目的 探讨平均心率、心率波动和心率变异性对64层螺旋CT冠脉造影成像质量的影响.方法 200例患者因怀疑存在冠心病进行64层螺旋CT冠状动脉造影检查,以5分法评定系统进行影像质量评价,着重分析平均心率、心率波动和心率变异性与冠状动脉图像质量的相关性.结果 200例患者,共纳入分析血管为600支,平均心率为69.20±8.80bmp,心率波动范围 1-38bmp,平均心率变异性8.50±6.75 %,共有94.3%(566/600)冠状动脉图像质量满足诊断需要.平均心率,心率波动和心率变异性与冠脉图像质量均有显著相关性.平均心率越慢,心率波动范围越小,心率

  19. 心率及其变异性对64层CT冠状动脉成像质量及辐射剂量的影响%Effects of heart rate and heart rate variability on image quality and radiation exposure of 64-slice coronary CT angiography

    贺敬红; 李健丁; 乔英; 张瑞平


    目的:评价心率及心率变异性对64层螺旋CT冠状动脉影像质量及辐射剂量的影响。方法共90例患者进行了64层螺旋CT冠状动脉成像,以4分评判方法进行图像质量评价,分析心率及心率变异性对冠状动脉的影像质量及辐射剂量的影响。结果90例患者,共360支血管纳入分析,其中97.5%可满足影像评价。平均心率为(67±10)次/min,平均心率变异性为(7.2±9.3)%,辐射剂量平均为(20.2±2.3)mSv。平均心率和心率变异性与冠状动脉影像质量均呈负相关(r值分别为:-0.651、-0.662,P值均<0.01),与辐射剂量无相关性。结论不同心率、心率变异性患者,图像质量差异较大,降低心率,减少心率变异性有助于提高64层冠状动脉的成像质量,对辐射剂量无显著影响。%Objective To assess the effect of heart rate and heart rate variability on image quality and patient dose with 64-slice sprial CT coronary angiography. Methods Ninty patients underwent 64-slice coronary CT angiog-raphy.Image quality was performed usding four-score method.The analysis was performed to evaluate the relationship of heart rate and heart rate variability on the image quality and radiation dose. Results Three hundreds and sixty coronary arteries were analyzed in 90 patients, 97.5%of the coronary segments was sufficient for diagnosing. The aver-age heart rate was (67 ±10) beat per minute,with a variability of (7.2 ±9.3)%.The mean effective dose was (20.2 ±2.3) mSv.Significant negative correlations were observed both between heart rate and image quality and between heart rate variability and image quality. The results showed that heart rate and heart rate variability had no significant effect on radiation dose. Conclusion The image quality was significantly different in patients with different heart rate and heart rate variability.Reducing average heart rate and heart rate variability in

  20. 64排螺旋CT诊断成人门静脉海绵样变性的影像学表现及价值%Imaging Findings and Value of 64-slice Spiral CT in Diagnosis of Cavernous Transformation of Portal Vein

    施健; 施小平; 王强; 王勤英


    目的 探讨利用64排螺旋CT动态增强扫描技术及多种血管重建方法诊断门静脉海绵样变性(Cavernous transformation of portal vein,CTPV)的价值和意义.方法 10例经手术、数字血管造影、超声诊断证实的门静脉海绵样变性病例,均行腹部平扫和动态增强扫描及血管后处理成像.结果 门静脉海绵样变性主要表现为门脉主干和(或)分支的阻塞,门脉走行区正常结构消失,出现大量向肝性及离肝性侧枝静脉.通过VR、MIP、MPR等血管成像技术能很好的显示门静脉栓塞、侧枝血管的重建与开放情况.结论 64排螺旋CT动态增强扫描及血管成像技术对诊断门静脉海绵样变性及侧枝血管的显示有较大优势和意义.%Objective To evaluate 64-slice spiral CT dynamic contrast-enhanced scanning combined with angiography reconstruction techniques in diagnosis of cavernous transformation of portal vein (CTPV). Methods 10 patients with CTPV conformed by surgery, digital angiography and ultrasound underwent plain and dynamic contrast enhanced CT. Multiple angiography reconstruction techniques were used to obtain vascular post-processing images. Results CTPV was primarily characteristic of the portal vein and (or) branch obstruction, loss of normal structure of portal vein region, presence of abundant venous collaterals through and out of liver. Volume rendering view (VR), maximum intensity projection (MIP) and multiplanar reconstruction (MPR) could distinctly display the portal vein embolization as well as reconstruction and opening situation of collateral vessels. Conclusion 64-slice spiral CT dynamic contrast-enhanced scanning combined with angiography reconstruction techniques is capable of making an accurate diagnosis of CTPV and providing more information for clinical therapy decisions.

  1. Use of 64-slice Spiral CT Angiography of Renal Vein Imaging in Evaluating Renal Vein Abnor-malities%64层3DMSCT在肾静脉异常中的应用价值

    侯伟伟; 王云华; 蒋中标; 郑凯


    【目的】探讨64层多排螺旋CT(MSCT)三维血管成像(3D MSCTA)在肾静脉中的诊断价值。【方法】收集拟行活体肾移植术供肾者96例,临床可疑胡桃夹综合征者5例,行64层3D M SC T A ,了解肾脏静脉血管起始、数目、分支走行及管径大小,进一步比较3D MSCTA各种图像后处理重建方法对肾静脉异常的显示效果。【结果】双肾静脉均为一支且其起源与走行正常者66例。肾静脉变异35例:包括2条右肾静脉者4例,3条右肾静脉者2例,主动脉后肾静脉者1例,肾静脉细小(考虑可疑胡桃夹综合征)者5例,性腺静脉和或腰静脉及左肾上腺静脉(左肾静脉常见属支)汇入左肾静脉主干者20例,2条左肾静脉者3例(2条肾静脉分别与腹主动脉前后分别汇入下腔静脉者1例;1条肾静脉汇入下腔静脉、一条肾静脉汇入半奇静脉者1例;1条肾静脉汇入下腔静脉、一条肾静脉汇入左髂总静脉者1例)。与手术所见完全一致者为99例,符合率为98%(99/101)。【结论】64层3D MSCTA结合适当的后处理重建方法可满意显示肾静脉正常解剖及变异情况,是评价各种肾静脉异常的准确、安全方法。%[Objective] To explore the use of 3‐dimensional 64‐slice Spiral computed tomography angiogra‐phy (3D MSCTA) in the diagnosis of renal veins .[Methods] A total of 96 cases of potential live renal donor and 5 cases of clinically diagnosed nut‐cracker sign (NCS) were examined by 64‐slice spiral computed tomo‐graphy angiography (CTA) .The origin ,number ,branch ,course and size of renal veins were observed .Fur‐ther comparisons were made for the capacities of deciphering renal vein abnormalities on all kinds of postpro‐cessing reconstruction images of 3D MSCT .[Results]Double renal vein with normal origins and courses were found in 66 cases .Among 35 cases of renal vein variation ,there were double right renal

  2. Synthetic streams in a Gravitational Wave inspiral search with a multi-detector network

    K, Haris


    Gravitational Wave Inspiral search with a global network of interferometers when carried in a phase coherent fashion would mimic an effective multi-detector network with synthetic streams constructed by the linear combination of the data from different detectors. For the first time, we demonstrate that the two synthetic data streams pertaining to the two polarizations of Gravitational Wave can be derived prior to the maximum-likelihood analysis in a most natural way using the technique of singular-value-decomposition applied to the network signal-to-noise ratio vector. We construct the network matched filters in combined network plus spectral space which capture both the synthetic streams. We further show that the network LLR is then sum of the LLR of each synthetic stream. The four extrinsic parameters are mapped to the two amplitudes and two phases. The maximization over these is a straightforward approach closely linked to the single detector approach. Towards the end, we connect all the previous works rel...

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

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


    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)

  4. Bronchial anatomy of left lung: a study of multi-detector row CT.

    Zhao, Xinya; Ju, Yuanrong; Liu, Cheng; Li, Jianfeng; Huang, Min; Sun, Jian; Wang, Tao


    Familiarity with prevailing pattern and variations in the bronchial tree is not only essential for the anatomist to explain bronchial variation in bronchial specimens, but also useful for guiding bronchoscopy and instructing pulmonary segmental resection. The purpose of this study was designed to demonstrate various branching patterns of left lung with 3D images, with special attention given to identify the major types at transverse thin-section CT. Two hundred and sixteen patients with routine thorax scans were enrolled. The images of bronchial tree, virtual bronchoscopy were reconstructed using post-processing technique of multi-detector row CT. We attempted to classify the segmental bronchi by interpreting the post-processing images, and identified them in transverse thin-section CT. Our results showed that the segmental bronchial ramifications of the left superior lobe were classified into three types mainly, i.e., common stem of apical and posterior segmental bronchi (64%, 138/216); trifurcation (23%, 50/216); common stem of apical and anterior segmental bronchi (10%, 22/216), and they could be identified at two typical sections of transverse thin-section CT. There were two major types in left basal segmental bronchi, i.e., bifurcation (75%, 163/216), trifurcation (18%, 39/216), and they could also be identified at two typical sections of transverse thin-section CT. In conclusion, our study have offered simplified branching patterns of bronchi and demonstrated various unusual bronchial branching patterns perfectly with 3D images, and have also revealed how to identify the main branching patterns in transverse thin-section CT.

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

    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


    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.

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

    Foley, P T; Ganeshan, A; Anthony, S; Uberoi, R


    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.

  7. Clinical application analysis of 64-slice CT coronary CTA dynamic volume rendering diagnosis of myocardial bridge & nbsp;of the anterior descending branch%64层螺旋CT冠状动脉CTA动态容积再现辅助诊断前降支心肌桥的临床应用分析



      Objective To explore the clinical value of 64-slice CT coronary CTA dynamic volume rendering images auxiliary diagnosis of myocardial bridge. Methods 96 patients underwent coronary CTA from January 2009 to the end of December 2012, with confirm of coronary angiography, were chosen. CT images are routinely reconstructed in the best phase period and in 0-90% phase period, an interval of 10%. Reconstruction data was sent to the workstation to get the MPR, the CPR, as well as dynamic volume rendering images. Images were analyzed by the two groups of doctors of medical imaging department to determine whether the presence of myocardial bridge of the left anterior descending artery based on static images, both static and dynamic volume images, respectively. Results 96 cases with myocardial bridge of the left anterior descending artery confirmed by coronary angiography, 83 cases were diagnosed by the static CTA image, 93 cases were diagnosed by both static and dynamic volume images. The sensitivity of two groups was 93.75% and 82.29%, specificity 99.68% and 99.57%, respectively. Conclusion The comprehensive analysis of the 64-slice spiral CT coronary CTA static and dynamic volume rendering images can improve the accuracy of the diagnosis of left anterior descending artery myocardial bridge.%  目的探索64层螺旋CT冠状动脉CTA动态容积再现图像辅助诊断心肌桥的临床应用价值。方法选择我院2009年1月-2012年12月行冠状动脉CTA检查并经冠脉造影证实的心肌桥96例,所有CT图像均进行常规best phase期相重建及0-90%、间隔10%的多期相重建,重建后的数据传送至工作站进行MPR、CPR重建以及动态容积再现处理。图像由两组医师分别根据静态图像、静态加动态容积再现图像判断是否存在前降支心肌桥,诊断结果分别统计,并进行统计学分析。结果经冠脉造影证实的前降支心肌桥患者96例中,静态CTA图像诊断肌桥83例,静

  8. Using the 64-slice Perfusion CT to Evaluate the Oxygen Tension(pO2) in the Rabbit VX2 Tumor Model: An Experimental Study%64层灌注CT评价兔VX2体部肿瘤模型氧分压的实验研究

    孙昌进; 肖明勇; 阴俊; 于金明; 郞锦义; 王光辉; 李超; 李涛; 罗云秀; 吕海波; 张德康; 李彦; 黄建鸣


    Objective: To investigate the role of the 64-slice perfusion CT in the evaluation of the oxygen tension ( pO2 ) in the rabbit VX2 tumor model. Methods: Forty-five rabbit VX2 brain tumor model established successfully were examined with 64-detector row CT. Tumor specimens were assessed for the oxygen tension ( pO2 ) , perfusion, blood volume ( BV) , peak enhancement intensity ( PEI) and time to peak (TTP) , and Pearson correlation coefficients were conducted to represent the relationships between the perfusion parameters and pO2 of the tumor. pO2was measured by oxygen-sensitive electrodes guided by perfusion CT images. Results: Mean values for perfusion,BV,PEI, TTP and pO2 of the 45 tumors were 27. 102 ± 26. 723ml/min, 22. 1 96 ± 13. 680ml/100g,43. 456 ±28.73 HU, 38.823 ±14.759 sec,and 15.981 ± 14.815mmHg, respectively. BV,PEI, TTP were not significant correlated with pO2 (r =0.271, 0. 253 、- 0. 18 , P > 0. 05 ) , whereas positively correlation was found between perfusion with pO2 ( r = 0. 673, P = 0. 00 ). Conclusion: The perfusion value from 64-slice spiral CT perfusion imaging might to have ability to evaluate the tumor pO2%目的:利用64层灌注CT评价兔VX2肿瘤模型氧分压并与氧微电极法对照.方法:对45只成功建模兔VX2脑瘤模型行灌注CT检查.测量脑瘤兴趣区灌注值(perfusion)、血容量(blood volume,BV)、达峰时间(time to peak TTP)、最大峰值(peak enhancement intensity,PEI).结果与该兴趣区氧微电极法测得氧分压(PO2)对照.结果:45例成功建模兔VX2脑瘤兴趣区灌注值范围为1.3 ml/min~127.0 ml/min,平均为27.102 ml/min±26.723 ml/min;BV为1.2 ml/100g~53.1ml/100g,平均为22.196 ml/100g±13.680ml/100g,PEI为8.7 HU~124.6HU,平均为43.456 HU±28.73 HU; TTP为8.2 sec~62.5 sec,平均为38.823 sec±14.759 sec;对应区域PO2为0.14 mmHg~46.70mmHg,平均为15.981 mmHg±14.815mmHg.灌注值与对应区域PO2相关系数为0.673,有统计学意义(P=0.00).BV

  9. Application of 64-slice CT for Dental Panoramic Imaging in Orthodontic Treatment of Maxillary and Mandibular Embedded Teeth%64层螺旋CT全景齿科成像技术在上、下颌骨埋伏牙矫形中的应用

    邓海平; 曹军; 李建胜


    Objective To explore the clinical value of 64-slice CT for dental panoramic imaging technology in orthodontic treatment of maxillary and mandibular embedded teeth. Methods Fifty patients with maxillary and mandibular embedded teeth underwent 64-slice spiral CT examination. By using Dentascan soft ware, multi-planar reconstruction (MPR), curved planar reconstruction (CPR), maximum intensity projection (MIP), volume rendering (VR) and shaded surface display (SSD) reconstruction, tooth section was observed from different angles and 3-D images were obtained to determine the shape of embedded teeth, labial side and palatine side location,the position of reconstruction window, eruption direction, incision direction, and their relationship with adjacent teeth. Results Among the 65 maxillary and mandibular embedded teeth of 50 patients, 38 impacted teeth were found in 38 patients and 27 embedded supernumerary teeth in 12 patients. Three-dimensional reconstruction of spiral CT images could accurately show the number of maxillary and mandibular embedded teeth,the shape of crowns and roots,labial side and palatine side location,eruption direction,and their anatomical relationship with adjacent teeth. Conclusion Multislice spiral CT for dental panoramic imaging technology is of great significance in di-agnosis of embedded teeth and can be clinically used as an effective examination for surgical treatment and orthodontic therapy of embedded teeth.%目的 探讨64层螺旋CT全景齿科成像技术在上、下颌骨埋伏牙矫形中的临床应用价值.方法 对50例上、下颌骨埋伏牙患者均行64层螺旋CT检查,并用Dentascan软件包及多平面重建(MPR)、曲面重建(CPR)、最大密度投影(MIP)、容积再现(VR)及表面遮盖成像(SSD)重建图像,从不同的角度观察牙体断面及三维立体图像,从而获得埋伏牙的牙体形态、唇腭侧位置、开窗的位置、萌出方向、切口方向及与其邻牙关系.结果 50例患者中,

  10. Determination of the weighted CT dose index in modern multi-detector CT scanners.

    Perisinakis, K; Damilakis, J; Tzedakis, A; Papadakis, A; Theocharopoulos, N; Gourtsoyiannis, N


    The aim of the present study was to (a) evaluate the underestimation in the value of the free-in-air (CTDI(air)) and the weighted CT dose index (CTDI(w)) determined with the standard 100 mm pencil chamber, i.e. the CTDI(100) concept, for the whole range of nominal radiation beam collimations selectable in a modern multi-slice CT scanner, (b) estimate the optimum length of the pencil-chamber and phantoms for accurate CTDI(w) measurements and (c) provide CTDI(w) values normalized to free-in-air CTDI for different tube-voltage, nominal radiation beam collimations and beam filtration values. The underestimation in the determination of CTDI(air) and CTDI(w) using the CTDI(100) concept was determined from measurements obtained with standard polymethyl-methacrylate (PMMA) phantoms and arrays of thermoluminescence dosimeters. The Monte Carlo N-Particle transport code was used to simulate standard CTDI measurements on a 16-slice CT scanner. The optimum pencil-chamber length for accurate determination of CTDI(w) was estimated as the minimum chamber length for which a further increase in length does not alter the value of the CTDI. CTDI(w)/CTDI(air) ratios were determined using Monte Carlo simulation and the optimum detector length for all selectable tube-voltage values and for three different values of beam filtration. To verify the Monte Carlo results, measured values of CTDI(w)/CTDI(air) ratios using the standard 100 mm pencil ionization chamber were compared with corresponding values calculated with Monte Carlo experiments. The underestimation in the determination of CTDI(air) using the 100 mm pencil chamber was less than 1% for all beam collimations. The underestimation in CTDI(w) was 15% and 27% for head and body phantoms, respectively. The optimum detector length for accurate CTDI(w) measurements was found to be 50 cm for the beam collimations commonly employed in modern multi-detector (MD) CT scanners. The ratio of CTDI(w)/CTDI(air) determined using the optimum

  11. 64排螺旋CT功能成像技术在兔急性肾损伤诊断中的价值%Value of 64-slice spiral CT functional imaging techniques for diagnosis of acute kidney injury in rabbits

    赵效新; 王新宇; 王文红; 李亚军; 孙浩然; 孟祥鹿; 顾程


    Objective To quantitatively assess renal hemodynamic changes in hypertensive acute kidney injury in rabbits induced by L-NAME using 64-slice spiral CT functional imaging techniques,and to explore the application of these techniques in evaluation of early kidney functional changes.Methods Fourteen female New Zealand white rabbits were randomly divided into normal control group (n=6)and L-NAME group (n=8).The control group was injected NaCl solution and the L-NAME group was injected the same amount of L-NAME solution to make hypertensive acute kidney injury model.64-slice spiral CT and SPECT were scanned af-ter injection.Blood samples were collected before and after injecting NaCl and L-NAME solution to detect serum creatinine (Cr).Cr level and CT perfusion parameters of the two groups were analyzed and compared with the pathology results.GFRCT detected by con-trast-enhanced CT and GFRSPECT detected by SPECT were analyzed by the rank correlation test.Results Renal blood volume,blood flow,permeability surface,time to peak,and peak value had statistically significant differences between the control and L-NAME group (P <0.05).GFRCT and GFRSPECT had obvious correlation.GFRCT of L-NAME group was obviously lower than that of the con-trol group.The kidneys of L-NAME group showed obviously injured under both light microscope and microscope.Conclusion 64-slice spiral CT functional imaging techniques can dynamically observe and quantitatively assess early hypertensive kidney dysfunc-tion,especially unilateral renal blood flow abnormalities.It is an effective examination in quantitatively assessing kidney function.%目的:利用64排螺旋 CT 功能成像技术定量分析 N-硝基-L-精氨酸甲酯(L-NAME)致兔高血压急性肾损伤后肾血流动力学变化,探讨该技术在评估早期肾功能损伤中的应用价值。方法将14只雌性新西兰大白兔随机分成正常对照组(n=6)和 L-NAME 组(n=8)。对照组注入氯化钠(NaCl)溶液,L-NAME

  12. The influence of heart rate,heart rate variability and electrocardiogram editing on image quality of 64-slice CT coronary angiography in patients with atrial fibrillation%心室率、心室率波动及心电编辑对心房颤动患者64层螺旋CT冠状动脉成像质量的影响

    杨琳; 张兆琪; 范占明; 徐超; 赵蕾; 晏子旭; 姜红


    Objective To prospectively evaluate the influence of average heart rate,heart rate variability and ECG editing on image quality of 64-slice CT coronary angiography(CTCA)in patients with atrial fibrillation(AF).Methods Fifty patients who were diagnosed with AF underwent respective ECG-gating 64-slice CTCA Image quality(good,moderate,poor)were evaluated on vessel segment level pre-and post ECG editing.Chi-square test was performed to compare the image quality in patients with various average heart rate,heart rate variability,and pre-and post ECC editing.Pearson correlation analysis was performed to test the relationship between the image quality and average heart rate and heart rate variability.Sensitivity,specificity,positive predictive value(PPV)and negative predictive value(NPV)were calculated by using the conventional angiography as the standard reference.Results The average heart rate of the fifty AF patients was(89±23)beat/min,with variability of(18.2±6.1)beat/min.Finally,24(3.4%)segments were considered to have poor image quality in 6(12.0%)patients.Image quality decreased significantly(P<0.05)at the average heart rate of over 100 beats per minute(11 segments)or the standard deviation of heart rate of over 24 beats per minute(11 segments).There was significant correlation between the mean heart rate and the image quality for all segments,the RCA,and distal section of coronary artery(r=0.50,0.55,0.53,0.49,0.42,0.44;P<0.05).Heart rate variability was also significant correlated with the image quality.There was significant difference on image quality pre-and post ECG editing(P=0.013).The respective overall sensitivity,specificity,NPV,PPV values were 100%(6/6),93.2%(41/44),100%(41/41),and 66.7%(6/9).Conclusion ECG editing can improve the success rate and the image quality of 64-slice CTCA effectively in patients with AF within a certain range of average heart rates and heart rate variability.%目的 探讨不同心室率、心室

  13. 下肢动脉闭塞性疾病64层CT血管成像中腘动脉小剂量对比剂试验的意义%64-slice CT angiography in lower extremity peripheral arterial occlusive disease: clinical value of test injection at popliteal arteries

    舒政; 邓小飞; 葛琛瑾; 孙凤; 邹银鸽; 孟文斌


    Objective To investigate the clinical value of the test injection at popliteal arteries on 64-slice CTA in lower extremity peripheral arterial occlusive disease (PAOD). Methods Twenty-eight patients with PAOD referred for 64-slice CTA were enrolled consecutively in the study. Test injection was performed at bilateral popliteal arteries (the level of knee joints) and the clinic value of the peak value and the time to peak was analyzed. The relationship between the time to peak and the peak value was evaluated with Pearson test. The time to peak was used for programming of the CT angiographic acquisitions with fast scanning mode. The quality of visualization of each arterial segment was determined independently by two radiologists. Results Fifty-four (96%, 54/56) time-attenuation curves were obtained in 28 patients. The wide interindividual variation in the peak value and the time to peak was observed in 52 curves of 26 patients with range of 60-178 HU,21-46 s and an average of (135±28) HU,(31±6) s, respectively. The difference in the peak value and the time to peak between bilateral popliteal arteries was also observed with range of 10-80 HU and an average of (32±18) HU in 19 patients,with range of 1-12 s and an average of (5±3) s in 21 patients. There was negative relationship between the peak value and the time to peak (r=-0.526, P<0.01). The CTA images were of good (598 segments) or medium quality (12 segments) in 99% segments (610/616). Conclusions The test injection at popliteal arteries was useful for 64-slice CTA in the patients with PAOD, as it could accurately specify the delay time of CT angiographic acquisitions.%目的 探讨下肢动脉闭塞性疾病采用64层CT血管成像时,在腘动脉行小剂量对比剂试验的意义.方法 连续选取28例临床怀疑下肢动脉闭塞性疾病患者,应用64层CT在两侧腘动脉(膝关节层面)各设置一ROI进行小剂量对比剂试验,明确显示峰值及达峰时间者认为曲线获取成功.

  14. Tracheobronchial tumor:evaluation by using 64-slice spiral CT with multiplanar and three-dimensional reconstructions%64层螺旋CT三维重建在气管主支气管肿瘤诊断中的应用

    张蕴; 荐志洁; 赵婷婷; 石志红; 朱柏


    Objective To evaluate the roles of 64-slice spiral CT with multiplanar and three-dimensional reconstructions in the di-agnosis of tracheobronchial tumor. Methods 39 cases were undergone CT scan for chest using TOSHIBA Aquilion 64 or PHILIPS Brilliance 64 system. The post-processing techniques included volume rendering (VR), virtual bronchoscopy( VB) , multiplanar re-construction (MPR) , minimum intensity projection(MinIP) in Vitrea 2 workstation. The CT manifestations were analyzed, and compared with the results of the operation and bronchoscopy. Results The tumor located in trachea in 9 cases, right main bronchus in 15 cases, left main bronchus in 13 cases. The tumors were in large airway widely in 2 cases. All of cases showed the filling defect in airway. The degree of lumen stenosis was the first grade in 1 case, the second grade in 0 case, the third grade in 14 cases, the forth grade in 24 cases. The thickening of the walls of the trachea or bronchus in 14 cases, both thickening of the walls and extralu-minal extensions in 23 cases, there was not any thickening of the walls in 2 cases. The edge of the tumor showed smooth in 2 cases, irregular in 37 cases. Benign tumor was in 3 cases, including benign mesenchymoma, leiomyoma, and pleomorphic adenoma in 1 case,respectively. Malignant tumor was in 36 cases, including small cell carcinoma in 8 cases, adenocarcinoma in 1 case, squamous cell carcinoma in 25 cases, mucoepidermoid carcinoma in 1 case, papillary thyroid cancer in 1 case. The diagnostic accuracy was 97. 44% using of 64-slice spiral CT with multiplanar and three-dimensional reconstructions. Conclusion 64-slice spiral CT with multiplanar and three-dimensional reconstructions is a valuable method in the diagnosis and the differential diagnosis of the tracheobronchial benign and malignant tumors, stent planning and follow-up.%目的 探讨64层螺旋CT三维重建在气管、主支气管肿瘤诊断中的应用价值.方法 39例均接受64层螺旋CT胸部

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

    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)


    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.)

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

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


    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.

  17. 扫描方式对64层螺旋CT头颅 CTA图像质量和辐射剂量影响的研究%Comparison study of image quality and radiation dose between helical and axial CT angiography of the head with 64-slice helical CT

    戴贵东; 肖正远; 兰永树; 粱卡丽


    目的:探讨64层螺旋CT扫描方式对头颅CTA图像质量和辐射剂量的影响.方法:采用GE Lightspeed VCT 对100例需要行头颅CTA检查的患者进行对比研究,50例行螺旋扫描,另50例行轴层扫描.两组数据经过VR、MIP、去骨VR和多平面重组等方法后处理,然后由3组医师通过5分评价法对CTA图像质量进行主观评价,取其均值纳入统计学分析;记录每组扫描的容积剂量指数(CTDIvol)和剂量长度乘积(DLP).对两组数据进行两独立样本t检验.结果:轴向扫描图像质量评分是(4.66±0.42)分、螺旋扫描CTA的成像质量评分(4.67±0.38)分;两组数据差异无统计学意义(P>0.05).轴向扫描、螺旋扫描的CTDIvol分别是45.71和54.18mGy; DLP分别是731.43和954.68mGy·cm.两组间差异有统计学意义(P<0.05),轴层扫描方式辐射剂量更低.结论:64层CT头颅CTA轴扫可以显著降低辐射剂量而不降低图像质量,在临床运用中值得关注.%Objective: To compare the difference in image quality and radiation dose between helical and axial CT angiography of the head with 64 slices helical CT. Methods:100 patients with suspected or confirmed cerebrovascular disease in our hospital,were divided into two groups to accept CTA examination :helical scanning group (50 cases) and axial scan ning group (50 cases). Except the parameter of scanning method,each group was examined with the same scan parameters and equipment. 80ml contrast medium was injected (via a cubital vein) by 4. 3ml/s and followed by 35ml normal sodium at the same speed. The cerebral vessels were imaged by these postprocessing methods: maximum intensity projection (MIP) volume rendering (VR) ,and "Auto Select" technique. Three group of doctors evaluated the image quality by means of 5 point scoring subjective evaluation. The radiation dose report was auto generated, trie average value ol volume CT dose index (CTDIvol) and dose length product (DLP) were taken into the sheet. All the data

  18. 周围型肺癌64层螺旋CT征象、病理分型与CCR7表达相关性研究%Studies on the correlation between the 64-slice CT features, pathologic classifications and expression of CCR7 in peripheral lung cancer

    赵胜祥; 张琴; 陈朝晖


    Objective To explore the expression relationship between 64-slice CT features and the CCR7 (CC chemokine receptor 7) in peripheral lung cancer.Methods The data of 26 cases of peripheral lung cancer confirmed by operation and pathological classifications were clected.All patients had MSCT scan before operation,and without radiotherapy or chemotherapy.The expression of CCR7 was examined by means of SP immunohistochemical technology (Max Vision TM) in the 26 patients,and compared with the 64-slice CT features of lung cancer with the CCR7 immunohistochemical test results,data was analysed by SPSS 17.0 statistical software,the rate was compared with fisher exact method test,P <0.05 and the difference was statistically significant.Results ① The expression of CCR7 in the adenocarcinoma with positive expression rate was 75.0% (15/20),and in squamous cell carcinoma the positive expression rate was 33.3% (2/6),in the peripheral lung cancer,P <0.05,the difference was statistically significant; ② The expression of CCR7 in the cancer size of ≤3.0 cm the positive expression rate was 75.0% (15/20),and in the cancer size of > 3.0 cm the positive expression rate was 33.3% (2/6),P <0.05,the difference was statistically significant; ③ It was not associated between the expression of CCR7 and CT signs of the tumor deep lobulation,spiculate protuberance,vacuole sign,pleural indentation,spiculation,mediastinal lymph node metastasis,(P >0.05).Conclusion The positive expression of peripheral lung cancer of CCR7 is related to pathologic type,not associated with the diagnostic CT features.%目的 探讨周围型肺癌CT征象与CCR7(CC chemokine receptor 7,CC类趋化因子受体7)表达的关系.方法 收集资料完整并经手术、病理证实的周围型肺癌26例.全部患者术前均行64层螺旋CT平扫及增强扫描,术前未进行放射治疗或化疗.应用免疫组织化学染色(MaxVisionTM二步法)检测26例周围型肺癌中CCR7的表达水

  19. 64-slice spiral CTA in evaluation on the changes of hepatic vessels and the portosystemic collateral circulation in liver cirrhosis%64排螺旋CT血管造影评价肝硬化血管改变及侧支循环

    李妙玲; 赵婷婷; 袁会军; 孙兴旺; 强永乾


    Objective To investigate the changes of hepatic vessels and the portosystemic collateral circulation in patients with liver cirrhosis with 64-slices spiral CTA. Methods Tri-phase enhanced CT scan of whole hepatic region were performed in 168 patients with liver cirrhosis (liver cirrhosis group) and 120 patients without liver cirrhosis (control group). All images were post processed with MIP and VR, and were compared between the two groups. Results The difference between the two groups were statistically significant (P<0. 01) in showing hepatic artery, portal vein and hepatic vein of different grades, except in showing 1 st grade of portal vein and hepatic vein (P=0. 51, 0. 08). In liver cirrhosis group, dilated trunk of hepatic artery and portal vein were observed in 85 patients, narrowing and tortuosity of vessels were observed in 98 patients, carcinoma thrombus formation and spongy degeneration in portal vein were detected in 9 and 8 patients, respectively, while continuous enhancement of hepatic artery and portal vein were noticed in 55 and 57 patients, respectively. In the control group, dilated trunk of hepatic artery and portal vein were observed in 3 patients, narrowing and tortuosity of vessels were observed in 2 patients, continuous enhancement of hepatic artery and portal vein were noticed in 4 and 3 patients, respectively. Totally 258 portosystemic collateral circulations were found in liver cirrhosis group, including 196 esophagogastric varices (196/258, 75. 97%), whereas only 2 retroperitoneal shunts were found in control group. Conclusion 64- slices spiral CT tri-phase angiography is a safe, convenient and reliable method to display the changes of hepatic vessels and the form of portosystemic collateral circulation, especially esophagogastric varices in patients with liver cirrhosis.%目的 探讨MSCTA评价肝硬化肝脏血管的异常改变及侧支循环形成的价值.方法 对168例肝硬化患者(肝硬化组)及120例无肝硬化的患者(

  20. 螺旋64排 CT 灌注成像对局灶结节性良恶性增生的鉴别诊断价值%The identification effect of HCC and hepatic focal nodular hyperplasia of 64-slice spiral CT

    耿欣; 肖世骞; 曹毅; 李健; 周鑫


    目的:探讨常规超声(US)检查与64层螺旋 CT(CT)检查在肝癌及肝脏局灶性结节增生临床诊断中应用价值。方法2013年1月至2015年1月对84例经肝细胞穿刺活检或术后病理组织检查确诊为肝脏局灶性病灶分别行 US 检查及 CT 检查,分析两种诊断方法准确率,病灶大小数目及患者在 US 及 CT 中的影像学特征。结果US 在诊断肝脏良性病变中的符合率与 CT 相当(P >0.05),而在肝癌诊断中 CT 组诊断准确率显著高于 US 组(P <0.05)。CT 组在直径≤1cm 微小肿瘤诊断中的符合率大于 US 组(P <0.05)。与肝炎型假瘤、肝局灶性增生结节、肝血管瘤患者相比,原发性肝癌、转移性肝癌患者 CT 始消时间及持续时间更长(P <0.05)。结论与 US 相比,CT 对肝癌的诊断率更加准确,更尽早分辨出恶性病灶及微小病灶。且不同性质的肝脏局灶性病灶在 CT 中表现出不同的增强方式,能有效鉴别不同种类的肝脏局灶性病灶。%Objective To investigate the examination application value of hepatic focal nodular hyperplasia of routine ultrasound (US)examination and 64-slice CT (CT)of liver cancer and clinical diagnostics.Methods 84 patients with liver cell or a pathological tissue biopsy diagnosed as focal liver lesions were underwented with US examination and CT examination from June 2013 to June 2015.The diagnostic methods,focus the size and number of patients in the US and imaging features of CT of two groups were analyzed.Results The benign liver lesions fairly consistent rate of US and CT were no different(P > 0.05),while the HCC diagnosis diagnostic accuracy of CT group was significantly higher than the US group(P <0.05).The rate in tumor diagnosis≤ 1cm small diameter of CT Group was greater than US group (P <0.05).Hepatitis type pseudotumor,liver focal nodular hyperplasia,hepatic hemangioma compared with pa-tients with primary liver

  1. The Value of 64-slice Spiral CT with 3D Transparency Reconstruction in the Diagnosis of Inner ear Malformation:Analysis of 32 Cases%64排CT三维透明化重组在内耳畸形诊断中的应用

    王丹; 曹绍东; 申宝忠; 张同; 白荣杰; 王可铮; 徐艳


    目的 探讨三维透明化重组在内耳畸形诊断中的应用价值,为先天性内耳疾病提供准确的影像诊断和临床治疗信息.资料与方法 回顾32耳内耳畸形的64排高分辨率CT(HRCT)容积数据,行三维透明化重组处理,按内耳畸形分类总结三维透明化重组方法及影像表现.结果 32耳的三维透明化容积再现(VR)图像结合透明化多平面重组(MPR)图像均能很好揭示内耳畸形病变部位及程度,内耳病变整体显示方面及蜗窗、前庭窗、半规管等细节病变显示中透明化VR像及透明化MPR像明显优于轴位像及普通MPR像;在耳蜗内部结构的显示中,透明化MPR、轴位像及普通MPR像优于透明化VR像.32耳先天内耳发育畸形有以下几种:耳蜗未发育(2耳);共同腔畸形(4耳);不完全分隔Ⅰ型(2耳,2例患者对侧耳均为共同腔畸形);不完全分隔Ⅱ型(即Mondini型)(16耳,多合并前庭、半规管及前庭导水管畸形);单纯前庭-半规管畸形(2耳);单纯前庭导水管扩大(6耳).结论 三维透明化个性重组能准确}半价内耳先天性疾病的类型和程度,为临床治疗提供重要的参考依据.%Objective To investigate the role of 3D transparency reconstruction in displaying the inner ear malformation. Materials and Methods Thirty-two cases of inner ear malformation were analyzed retrospectively. The data of 64 slice HRCT were processed using 3D transparency reconstruction. The imaging findings were summarized according to the categorization of the disease. Results The malformations included cochlear aplasia(2 ears), Common cavity deformity (4 ears), incomplete partition Ⅰ (2 ears ), incomplete partition Ⅱ ( Mondini deformity ) ( 16 ears), vestibular and semicircular canal malformations(3 ears) and vestibular aqueduct dilate(6 ears). The site and degree of inner ear malformation were displayed clearly by 3D transparent reconstruction imaging and MPR transparent imaging. Transparent MPR and VR

  2. 造影剂注射速率对64层螺旋CT冠状动脉血管成像质量的影响%Effect of contrast injection rates on immaging quality of coronary angiography taken by 64-slice spiral CT

    沈栋; 潘昌杰


    目的 研究造影剂注射速率对64层螺旋CT冠状动脉血管成像质量的影响.方法 120 例冠状动脉血管造影患者随机均分成三组,分别用4.5、5或5.5ml/s的速率注射等量造影剂.应用64层螺旋CT进行扫描;采用团注实验测定延迟时间;分别在左冠发出层面横断面图像选择感兴趣区测量升、降主动脉衰减值(HU),利用多平面重建技术(MPR)于离出口约1cm处的正交横断面图像测量心脏血管(左主干、前降支、回旋支及右冠状动脉)的衰减值.结果 升、降主动脉及心脏血管三组间对比衰减均有统计学意义(P<0.01).心脏血管对比衰减与体重(r=-0.722)、体重指数(BMI)(r=-0.599)明显相关(P<0.05).以5ml/s速率注射造影剂获得的图像质量优于其它两组(P<0.01).结论 在心脏CT血管造影(CTA)中在扫描条件及造影剂的碘浓度一致情况下,以5ml/s注射速率给予造影剂可以获得良好的血管增强效果.%Objective To study the effect of contrast injection rates on immaging quality of coronary angiography taken by 64-slice spiral CT (64-MSCT). Methods A total of 120 patients undergoing coronary angiography was equally randomized to 3 groups, in which the contrast injection was performed at the flow rates of 4. 5, 5, and 5. 5 ml/s, respectively. The 64-MSCT scanner and scanning protocols were the same for each group. The scanning delay of CT was determined with a bolus test technique. The attenuation in Hounsfield units(HU) achieved after each injection rate was determined at regions of interest(ROIs) placed at the 1 cm origin of coronary arteries measured by multiplanar reconstructions (MPR), which included the left main artery (LMA), left anterior descending artery(LAD), left circumfiex artery(LCX) and right coronary artery(RCA). All data were analyzed with one way ANOVA. The quality of the coronary artery images was evaluated and compared. Results The mean attenuation achieved at each aortic site was

  3. 后置滤过器对64排螺旋CT冠状动脉成像质量影响的CATPHAN模型研究%Effect of various post-processing filters on image quality of 64-slice CT coronary angiography by using a Catphan phantom

    Syed Shareef Fahad; 宦坚; 张伟; 龚建平; 乔方; 朱建兵; 陈光强


    Objective To evaluate the effect of various post-processing filters on image quality of 64-Slice CT coronary angiography. Methods Catphan 600 underwent cardiac scans by using GE LightSpeed VCT. The scan techniques undergone at 120 kV, 600 mA, speed of 0. 35 s per 360° rotation, pitch of 0. 20, slice thickness of 625 mm. Cardiac images were reconstructed by using filters of Cl ( UC1) , C2 (UC2), C3 (UC3 ) and were constracted without filter ( NUC) to create four image sets from the same scanning. Image noises were measured, and CNR, SNR, MTF were calculated for the four sets. Difference was examined by using one-way analysis of variance. Results Significant difference was found in terms of SD,CNR,SNR, MTF 50% (P 0.05). MTF 10% was significantly lower for UC3 than fhat for the other three sets (P<0.05). Conclusion Different post-processing filters should be selected according to the clinical requirements, because of their different effect on SD,CNR,SNR and MTF.%目的 探讨不同后置滤过器对64排螺旋CT冠状动脉成像(CTCA)质量的影响.方法 使用GE LightSpeed VCT机,采用120 kV,600 mA,0.35s/360°,层厚0.625 mm,pitch 0.2对Catphan 600模型进行扫描.采像后对原始图像分别进行不使用后置滤过器和使用后置滤过器C1、C2、C3重建,得到4组图像(NUC组、UC1组、UC2组和UC3组).测量图像噪声(SD),计算对比噪声比(CNR)、信噪比(SNR)、调制传输函数(MTF).统计分析采用单因素方差分析.结果 NUC组、UC1组、UC2组和UC3组的SD、CNR、SNR及MTF 50%差异均有高度统计学意义(均P<0.001),NUC组、UC1组和UC2组的MTF 10%差异无统计学意义(均P>0.05);UC3组与其余3组的MTF 10%差异有高度统计学意义(均P<0.01).结论 不同后置滤过器对CTCA图像SD、CNR、SNR和MTF的影响不同,可根据不同临床需要适当选择.

  4. Multi-detector CT and 3D imaging in a multi-vendor PACS environment

    van Ooijen, PMA; Witkamp, R; Oudkerk, M; Lemke, HU; Inamura, K; Doi, K; Vannier, MW; Farman, AG; Reiber, JHC


    Introduction of new hard- and software techniques like Multi-Dectector Computed Tomography (MDCT) and 3D imaging has put new demands on the Picture Archiving and Communications System (PACS) environment within the radiology department. The daily use of these new techniques requires a good integratio

  5. Infections of the neck leading to descending necrotizing mediastinitis: Role of multi-detector row computed tomography

    Pinto, Antonio [Department of Diagnostic Imaging, A. Cardarelli Hospital, 80131 Naples (Italy)], E-mail:; Scaglione, Mariano; Scuderi, Maria Giuseppina; Tortora, Giovanni; Daniele, Stefania; Romano, Luigia [Department of Diagnostic Imaging, A. Cardarelli Hospital, 80131 Naples (Italy)


    Descending necrotizing mediastinitis is an acute, polymicrobial infection of the mediastinum, originating from odontogenic, oropharyngeal and cervical infections. Anatomical continuity of the fascial spaces between the neck and the mediastinum leads to an occasional mediastinal extension of deep neck infection as a serious sequela. An understanding of the anatomy of the deep spaces of the neck and familiarity with the imaging findings in descending necrotizing mediastinitis may allow rapid diagnosis and treatment of this rare and life-threatening complication of deep neck space infection. In this article, we discuss the current role of radiology in diagnosing descending necrotizing mediastinitis, in determining the level of infection and the pathways of spread of infections from the neck to the mediastinum and in planning a successful treatment.

  6. Quantification of aortic distensibility in abdominal aortic aneurysm using ECG-gated multi-detector computed tomography

    Ganten, Maria-Katharina [Deutsches Krebsforschungszentrum, Department of Radiology, Medical Physics in Radiology, Heidelberg (Germany); Ruprecht-Karls-University of Heidelberg, Department of Diagnostic Radiology, Heidelberg (Germany); Krautter, Ute; Tengg-Kobligk, Hendrik von; Delorme, Stefan; Kauczor, Hans-Ulrich [Deutsches Krebsforschungszentrum, Department of Radiology, Medical Physics in Radiology, Heidelberg (Germany); Boeckler, Dittmar; Schumacher, Hardy [Ruprecht-Karls-University of Heidelberg, Department of Vascular and Endovascular Surgery, Heidelberg (Germany); Stiller, Wolfram; Bock, Michael [Deutsches Krebsforschungszentrum, Department of Medical Physics in Radiology, Medical Physics in Radiology, Heidelberg (Germany); Kauffmann, Guenter W. [Ruprecht-Karls-University of Heidelberg, Department of Diagnostic Radiology, Heidelberg (Germany)


    To detect distensibility changes that might be an indicator for an increased risk of rupture, cross-sectional area changes of abdominal aortic aneurysms (AAA) have been determined using ECG-gated CT. Distensibility measurements of the aorta were performed in 67 patients with AAA. Time-resolved images were acquired with a four detector-row CT system using a modified CT-angiography protocol. Pulsatility-related cross-sectional area changes were calculated above and at AAA level by semiautomatic segmentation; distensibility values were obtained using additional systemic blood pressure measurements. Values were compared for small Oe< 5 cm (n=44) and large Oe> 5 cm (n = 23) aneurysms. The aorta could be segmented successfully in all patients. Upstream AAA distensibility D was significantly higher than at AAA level for both groups: means above AAA (at AAA) D{sub above} = (1.3 {+-}0.8) .10 {sup -5} Pa {sup -1} (D{sub AAA} = (0.6 {+-}0.5) .10 {sup -5} Pa {sup -1}) t-test p{sub D}<0.0001. Differences of the distensibility between smaller and larger aneurysms were not found to be significant. Distensibility can be measured non-invasively with ECG-gated CT. The reduction of distensibility within aneurysms compared to normal proximal aorta is subtle; the lack of difference between both small and large aneurysms suggests that this reduction occurs early in the aneurysm's development. Hence, reduced distensibility might be a predictive parameter in patients with high risk of aortic disease. (orig.)

  7. Diagnostic accuracy of triple-contrast multi-detector computed tomography for detection of penetrating gastrointestinal injury: a prospective study

    Saksobhavivat, Nitima [Faculty of Medicine Ramathibodi Hospital, Mahidol University, Department of Diagnostic and Therapeutic Radiology, Ratchathewi, Bangkok (Thailand); Shanmuganathan, Kathirkamanathan; Boscak, Alexis R.; Sliker, Clint W.; Bodanapally, Uttam K.; Archer-Arroyo, Krystal; Miller, Lisa A.; Fleiter, Thorsten R.; Alexander, Melvin T.; Mirvis, Stuart E. [University of Maryland School of Medicine, Department of Diagnostic Radiology and Nuclear Medicine, Baltimore, MD (United States); Stein, Deborah M.; Scalea, Thomas M. [University of Maryland School of Medicine, R. Adams Cowley Shock Trauma Center, Baltimore, MD (United States)


    Neither the performance of CT in diagnosing penetrating gastrointestinal injury nor its ability to discriminate patients requiring either observation or surgery has been determined. This was a prospective, single-institutional observational study of patients with penetrating injury to the torso who underwent CT. Based on CT signs, reviewers determined the presence of a gastrointestinal injury and the need for surgery or observation. The primary outcome measures were operative findings and clinical follow-up. CT results were compared with the primary outcome measures. Of one hundred and seventy-one patients (72 gunshot wounds, 99 stab wounds; age range, 18-57 years; median age, 28 years) with penetrating torso trauma who underwent CT, 45 % were followed by an operation and 55 % by clinical follow up. Thirty-five patients had a gastrointestinal injury at surgery. The sensitivity, specificity, and accuracy of CT for diagnosing a gastrointestinal injury for all patients were each 91 %, and for predicting the need for surgery, they were 94 %, 93 %, 93 %, respectively. Among the 3 % of patients who failed observation, 1 % had a gastrointestinal injury. CT is a useful technique to diagnose gastrointestinal injury following penetrating torso injury. CT can help discriminate patients requiring observation or surgery. (orig.)

  8. Lung cancer perfusion at multi-detector row CT: reproducibility of whole tumor quantitative measurements.

    Ng, Quan-Sing; Goh, Vicky; Fichte, Heinz; Klotz, Ernst; Fernie, Pat; Saunders, Michele I; Hoskin, Peter J; Padhani, Anwar R


    Institutional review board approval and informed consent were obtained for this study. The aim of the study was to prospectively assess, in patients with lung cancer, the reproducibility of a quantitative whole tumor perfusion computed tomographic (CT) technique. Paired CT studies were performed in 10 patients (eight men, two women; mean age, 66 years) with lung cancer. Whole tumor permeability and blood volume were measured, and reproducibility was evaluated by using Bland-Altman statistics. Coefficient of variation of 9.49% for permeability and 26.31% for blood volume and inter- and intraobserver variability ranging between 3.30% and 6.34% indicate reliable assessment with this whole tumor technique.

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

    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)


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

    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)


    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.)

  11. Multi-Detector row CT urography on a 16-row CT scanner in the evaluation of urothelial tumors

    Tsili, A.C. [University Hospital of Ioannina, Department of Clinical Radiology, Ioannina (Greece); University of Ioannina, Medical School, Ioannina (Greece); Efremidis, S.C.; Tsampoulas, C. [University Hospital of Ioannina, Department of Clinical Radiology, Ioannina (Greece); Kalef-Ezra, J. [University Hospital of Ioannina, Department of Medical Physics, Ioannina (Greece); Giannakis, D.; Sofikitis, N. [University Hospital of Ioannina, Department of Urology, Ioannina (Greece); Alamanos, Y. [University Hospital of Ioannina, Department of Hygiene and Public Health, Ioannina (Greece)


    The purpose of this study was to assess the role of multi-detector row CT urography (MDCTU), on a 16-row CT scanner in the evaluation of patients with painless hematuria, with emphasis placed in the detection of urothelial tumors. We retrospectively reviewed the MDCT urographies of 75 patients, referred for painless hematuria. The CT protocol included unenhanced images, obtained with a detector configuration of 16 x 1.5 mm and pitch of 1.2, nephrographic and excretory-phase images, obtained with a detector collimation of 16 x 0.75 mm and pitch of 1.2. Axial and coronal reformatted images were evaluated. Three-dimensional reformation of the excretory-phase images was performed using the volume-rendering technique. The standard of reference included clinical and imaging follow-up, cystoscopic, surgical and histologic findings. In 55 (73%) of 75 patients, the cause of hematuria was identified on MDCTU; the most common cause was urothelial cancer, including seven tumors with a diameter equal or smaller than 0.5 cm in diameter. Sixteen-row MDCTU provided satisfactory results in the investigation of patients with painless hematuria. The main advantage of the technique is its ability to detect uroepithelial malignancies. (orig.)

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

    Jaeckle, T; Stuber, G; Hoffmann, M H K; Jeltsch, M; Schmitz, B L; Aschoff, A J


    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.

  13. The evaluation of 64-slice spiral CT perfusion to hepatic fibrosis of dog model and the correlation research with pathologic and VEGF change%犬肝纤维化64排螺旋CT全肝灌注成像及与病理对照、VEGF表达的相关研究

    胡跃群; 章雅琴; 李丛蕊; 骆雷; 容鹏飞; 王维


    目的 利用64排螺旋CT全肝灌注模式成像测定中华田园犬肝纤维化模型的相关灌注参数并与病理对照来反映肝纤维化程度,分析其与VEGF表达水平的相关性.方法 采用腹腔注射50%四氯化碳油溶液辅以高脂饮食,建立犬肝纤维化模型,定期行64排螺旋CT全肝灌注成像及肝穿活检.根据病理分期分析各组CT灌注参数,并与VEGF表达水平作对照研究.结果 成功获得各期肝纤维化模型.对照组HAP(28.25 ±2.19) ml/(min·100 g),PVP( 53.53±10.71) ml/( min ·100 g),TLP(81.78±18.56) ml/(min·100 g);随肝纤维化程度加重,PVP、TLP持续性下降(P<0.05),HAP总体略呈上升趋势.PVP值、TLP值与肝纤维化程度呈负相关(P<0.01);VEGF表达水平随着肝纤维化程度的加重而明显增高(P<0.05).结论 腹腔注射四氯化碳油溶液辅以高脂饮食可以成功模拟人类从肝细胞变性、肝纤维化至肝硬化的全过程.64排螺旋CT全肝灌注成像克服了以往灌注成像的不足,且能反映肝纤维化各期的血流动力学变化趋势,VEGF可能在慢性肝病所致肝纤维化过程中起重要作用.%Objective To measure the perfusion parameters of liver fibrosis of dog model with 64-slice spiral CT,and compare with positive control to reflect the degree of liver fibrosis,and analyze the correlation with VEGF values.Methods Liver fibrosis was induced in dogs by intraperitoneal injection of CC14 and high fat diet.CT perfusion scan and liver biopsies were performed.The perfusion parameters were measured according to the liver fibrosis models,and the correlation with VEGF values was analyzed.Results The animals in experimental group were successfully induced different degree of liver fibrosis.In normal group,the hepatic artery perfusion,portal vein perfusion and total hepatic blood flow were (28.25 ±2.19)ml/(min · 100 g),(53.53 ± 10.71)ml/(min · 100 g) and (81.78 ± 18.56) ml/(min · 100 g).The PVP and TLP values of the

  14. Application of ECG editing soltware in coronary angiography using 64-slice CT in arrythmia patients%心电编辑软件在64层螺旋CT心律失常患者冠状动脉成像中的初步应用

    姚红霞; 张国富; 张鹏; 崔二峰; 杨鹏午


    目的:探讨64层螺旋CT冠状动脉成像心电编辑功能对于改善心律失常或心电图信号不明原因故障中冠脉成像质量的作用.方法:搜集30例在检查前已知心律失常或仅在检查过程中出现心律失常或检查过程中出现同步记录的心电图信号部分缺失的64层螺旋CT冠状动脉成像资料,使用心电图编辑功能,比较编辑前后重建的冠状动脉图像质量.结果:对于低心率(<70次/分)的房性早搏(扫描过程中出现一次),心电编辑软件可以有效改善其冠脉图像质量,编辑前后可评估率差异有统计学意义(P<0.05);对于房室传导阻滞、心电信号缺失冠脉图像质量可以有限度地改善,对房颤改善不明显.对于高心率(≥70次/分)的房性早搏(扫描过程中出现一次)、房室传导阻滞,心电编辑软件均可有限度地改善,对房颤改善不明显,编辑前后可评估率差异无统计学意义(P>0.05).对心率不同的两组心律失常,低心率组图像质量可评估率(74.74%)高于高心率组(66.07%),心电编辑软件均可改善两组图像质量,但两组间比较差异无统计学意义.对于窦性心律不齐,心率波动幅度越大,冠脉图像不可评估率越大,两组心电编辑后图像质量均得到明显改善,差异有统计学意义(P<0.05).结论:在检查前或检查过程中出现的心律失常或者不明原因出现心电信号的异常,使用心电编辑功能,能提高冠脉成像质量.%Objective : To investigate the value of ECG editing software in improving the image quality of coronary an giography with 64-slice spiral CT (MSCTCA) in patients having arrhythmia or unidentified synchronous ECG error. Methods : MSCTCA materials of 30 patients with previously known arrhythmia/arrhythmia merely occurred during MSCT CA/unidentified ECG mechanic error happened during examination were included in this study. Using ECG editing soft ware,the image quality of MSCTCA before and after

  15. The value of volume doubling time in diagnosis of solitry pulmonary nodules by 64-slice spiral CT%容积倍增时间在64层螺旋CT诊断孤立性肺结节中的价值

    安彩霞; 王云生; 杨丽娟; 桑俊文; 张文莉; 王哲; 贺进军; 张凤艳; 刘静


    目的 探讨容积倍增时间( DTV)在64层螺旋CT诊断孤立性肺结节(SPN)中的价值.方法 初次胸部CT检查后,于第一个月末及第三个月末行2次以上随访的SPN患者46例,分别采用普通平扫横断面测量直径及LungCARE软件测定体积,计算所有结节的直径倍增时间(DTD)和DTV,比较两种测量方法对恶性肺结节的诊断价值;并用Mann-Whitney U非参数检验方法评价DTV在恶性SPN不同复查时期及不同病例类型之间的差异.结果 经临床和病理证实,46例SPN患者中,恶性肺结节29例(包括18例腺癌和11例鳞癌)、良性肺结节17例.DTV法与DTD法在恶性SPN诊断中的灵敏度、特异度、阳性预测率、阴性预测率和Youden指数分别为93.10%、94.11%、96.42%、88.89%和0.87 vs.79.31%、70.59%、82.14%、66.67%和0.50,DTV法的诊断价值显著优于DTD法(x2=10.211,P< 0.05).腺癌与鳞癌患者第一个月末与第三个月末的DTV比较,差异无统计学意义(U=0.127和U=0.066,P均>0.05).第一个月末及第三个月末,腺癌患者恶性肺结节的DTV显著大于鳞癌患者(U=-3.193和U=-2.810,P均<0.01).结论 DTV法在64层螺旋CT诊断SPN中的效能优于DTD法.DTV可作为观察指标,评估不同性质SPN的生长特征,为肺结节的早期随访及定性诊断提供帮助.%Objective To discuss the value of volume doubling time (DTV) in diagnosis of solitry pulmonary nodules (SPN) by 64-slice spiral CT.Methods There were 46 cases which were underwent repeated follow-up CT at the first month and at the third month after the initial chest CT.We evaluated the value of DTV calculated by LungCARE volumetry software and diameter doubling time (DTD) calculated by diameter method in the diagnosis of SPN.We compared the difference of DTV in different kinds of SPN and in different follow-up periods by Mann-Whitney U test.Results Twenty-nine malignant nodules and seventeen benign nodules were confirmed in forty-six SPN cases

  16. Three dimensional reconstruction of the liver and the abdominal blood vessels based on the 64-slice spiral CT data%64排螺旋CT扫描数据的肝脏及腹腔血管三维重建的研究

    朱新勇; 方驰华; 焦培峰; 全显跃; 唐海亮; 鲍苏苏; 钟世镇


    目的 探讨利用64排螺旋CT扫描数据进行肝脏及其内部管道和腹腔血管的计算机辅助三维重建的准确性及临床意义.方法 利用64排螺旋CT薄层扫描正常人肝脏二维图像数据集,采用自主研发的医学图像处理系统对二维图像数据进行肝脏及其肝内管道、腹腔血管系统三维可视化重建,并对重建肝脏模型的体积与肝脏实际体积以及重建门静脉与64排螺旋CT后处理工作站采用容积再现法重建的门静脉进行对比研究.结果 肝动脉、门静脉和肝静脉系统三维效果逼真,立体感强,可任意角度旋转、观察;能够显示肝内各主要管道系统的空间位置关系,并准确地反映肝脏实际体积及肝内管道系统的真实情况.通过调节肝脏的透明度可同时显示肝脏和肝内动静脉、门静脉分支和腹腔动脉系统.计算机重建后的门静脉与螺旋CT后处理工作站容积再现法重建的门静脉完全一致.结论 计算机辅助的三维肝脏及其管道和腹腔血管系统能准确反映人体的真实结构,为肝脏的虚拟手术设计提供了可靠和真实的虚拟器官和血管系统.%Objective To explore the accuracy and practical significance of the 3-dimensional (3D) reconstruction of the liver and the abdominal blood vessels based on the data of 64-slice spiral computerized tomography (64S-SCT). Methods The 2D images of the liver and the abdominal blood vessels were collected after TLC-scanning with 64S-SCT. The 3D images of the liver, hepatic internal duct system and the abdominal blood vessels were reconstructed by the medical image processing system. The volume of the 3D reconstructed liver was compared with that of the actual liver measured by the 64S-SCT, and the portal vein of the reconstructed liver model was compared with that reconstructed by the Mxview workstation based on the 64S-SCT data. Results The 3D models of the liver, hepatic internal duct system and abdominal blood

  17. Morphometric evaluation of subaxial cervical spine using multi-detector computerized tomography (MD-CT) scan: the consideration for cervical pedicle screws fixation

    Chanplakorn, Pongsthorn; Kraiwattanapong, Chaiwat; Aroonjarattham, Kitti; Leelapattana, Pittavat; Keorochana, Gun; Jaovisidha, Suphaneewan; Wajanavisit, Wiwat


    Background Cervical pedicle screw (CPS) insertion is a technically demanding procedure. The quantitative understanding of cervical pedicle morphology, especially the narrowest part of cervical pedicle or isthmus, would minimize the risk of catastrophic damage to surrounding neurovascular structures and improve surgical outcome. The aim of this study was to investigate morphology and quantify cortical thickness of the cervical isthmus by using Multi-detector Computerized Tomography (MD-CT) sca...

  18. Multi-detector CT: review of its use in acute GI haemorrhage

    Anthony, S.; Milburn, S. [Department of Radiology, John Radcliffe Hospital, Oxford (United Kingdom); Uberoi, R. [Department of Radiology, John Radcliffe Hospital, Oxford (United Kingdom)], E-mail:


    The advent of multi-section computed tomography (CT) technology allows the non-invasive assessment of the arterial tree. Using current software, it is now possible to produce high-quality, angiographic-like images that can be used to plan and guide therapeutic procedures. One such clinical situation is the assessment of patients with acute gastrointestinal (GI) haemorrhage. Multi-section CT has a number of advantages over conventional angiography in this situation. The simplicity and non-invasive nature of the technique compared with conventional angiography make CT angiography possible in situations where conventional angiography is not available. Movement artefact from respiration and peristalsis is a common problem in the interpretation of conventional angiography; this is essentially abolished with rapid acquisition times and the use of multi-planar images to remove overlying bowel loops. Cross-sectional imaging with the ability for multi-planar reconstruction allows the accurate anatomical localization of the bleeding site, as well as an assessment of the underlying pathology: this can be used to plan therapy (embolization or surgery). The aim of this paper is to review the current use of CT in the investigation of patients with GI haemorrhage, illustrated with images from our Institution. For patients in whom GI endoscopy has failed to establish a diagnosis, we propose multi-section CT angiography as the initial imaging investigation in acute GI haemorrhage.

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

    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)


    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 (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.)

  20. Contribution to data acquisition software of Eurogram and Diamant multi detectors in an Unix/VXWorks environment; Contribution aux logiciels d`acquisition de donnees des multidetecteurs Eurogam et Diamant dans un environnement reparti Unix/VXWorks

    Diarra, C.


    Questions on nuclear matter, need to have new performant equipments. Eurogram is a 4 PI gamma radiations multi detector and a precious tool in gamma spectroscopy, but it is necessary to use a charged particles detector and in this aim Diamant is an Eurogram partner. These two multi detectors needed special software data acquisition systems. The whole of acquisition control and management is based on sun stations with unix system. 56 figs., 64 refs.

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

    Chung, Gi Chung; Han, Won Jeong; Kim, Eun Kyung [Department of Oral and Maxillofacial Radiology, School of Dentistry, Dankook University, Cheonan (Korea, Republic of)


    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 {mu}Sv (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.

  2. β受体阻滞剂对健康成人64层螺旋 CT冠状动脉造影左心室功能的影响%The effects of propranolol on the left ventricular function by 64-slice multi-slice computed tomography

    张春红; 刘军; 梁立华; 彭述平


    目的:研究64层螺旋 CT(64SCT)冠状动脉造影,β受体阻滞剂对健康成人左心室功能的影响。方法收集行64SCT 冠状动脉造影(64SCTA)检查未发现冠状动脉狭窄的被试178例,其中89例检查前未服用β受体阻滞剂(普萘洛尔),另外89例年龄和性别相匹配的患者(检查前心率>70次/min)服用β受体阻滞剂调整心率。记录用药前后心率(HR)、收缩压(SBP)和舒张压(DBP)及普萘洛尔剂量。测定左心功能指标:舒张末期容积(EDV)、收缩末期容积(ESV)、射血分数(EF)。未服用和服用普萘洛尔组左心功能结果应用配对 t 检验进行统计分析。结果未服用和服用普萘洛尔两组间的 SBP 和 DBP 的差异无统计学意义[分别为(124±14)mmHg 和(121±13)mmHg,t =1.04, P >0.05;(81±9)mmHg 和(79±10)mmHg,t=1.44,P>0.05;(1 mmHg =0.133 pKa)]。EDV 两组之间差异无统计学意义[分别为(127.5±16.4)ml 和(129.8±15.1)ml,t =-1.22,P >0.05],而 ESV和 EF 在这两组之间的差异有统计学意义[分别为(44.7±12.3)ml 和(47.3±13.4)ml,t =2.47,P <0.05;(65.1±8.4)%和(62.0±7.8)%,t =2.39,P<0.05];服用普萘洛尔组 ESV 不同程度的增加,而 EF 下降。结论64SCTA 应用β受体阻滞剂,可致 ESV 增加,EF 降低,而 SBP、DBP 和 EDV 的差异无统计学意义。%Objective To investigate the effects of propranolol on the left ventricular (LV)function by CT coronary angiography.Methods One hundred and seventy-eight subjects without coronary artery stenosis were examined by 64SCT coronary angiography (64SCTA).Eight-nine subjects did not take propranolol while another eight-nine age-and gender-matched subjects whose heart rates above 70 beats were chosen to take propranolol.The heart rate,systolic blood pressure (SBP),and diastolic blood pressure (DBP)before and after the administration of propranolol and the dosage of propranolol were recorded.The left ventricular function was calculated by parameters of end-diastolic volume(EDV),end systolic volume (ESV)and ejection fraction (EF).The paired-t test was used to compare the left ventricular function between the two groups (no taking and taking propranolol).Results There were no significant differences in the SBP and DBP between the groups without and with propranolol medication [(124 ±14)mmHg and (81 ±9)mmHg;(121 ±1 3)mmHg and (79 ±10)mmHg,respectively)].The EDV showed no significant differences between the two groups,but the ESV and EF showed significant differences between the two groups[(44.7 ±1 2.3)mL and (47.3 ±1 3.4)mL;(65.1 ±8.4)% and (62.0 ±7.8)%,respectively)]. Conclusions Taking propranolol increases ESV and decreases EF,while the SBP,DBP and EDV don′t change.

  3. 腹腔神经节的多层螺旋CT表现%Multi-Detector CT Findings of Celiac Ganglia

    王梅; 张龙江; 路莉; 卢光明


    Objective To study the multi-detector CT findings of celiac ganglia. Materials and Methods Abdominal non-enhanced and enhanced multi-detector CT data of 133 subjects with normal findings were retrospectively reviewed. The location, morphologic feature, and size of the celiac ganglia were recorded and measured. Results Left celiac ganglia were showed in 124 subjects, not showed in 9 subjects, while right celiac ganglia were showed in 115 subjects and not showed in 18 subjects. There were no statistical difference for the display of celiac ganglia between left and right side (93. 2% vs 86. 5% , x2 = 3. 339, P = 0. 068 ) . Celiac ganglia were identified at the level between the origins of celiac and superior mesenteric arteries. The left ganglia was located between the left adrenal gland and diaphragm, and the right were identified posteromedial to the inferior vena cava and the inside of the right adrenal gland. They were thread-like (74. 5% , 178/239) or lobulated (25. 5% , 61/239). The mean long-axis dimensions of the left and right were (26. 1 ± 12.3) mm, (29. 5 ± 9. 2 ) mm, the left celiac ganglia were smaller than the right (t = - 4. 208,P < 0.001) . The mean short-axis dimensions of the left and right ganglia were (4. 1 ±1.0) mm, (3.1±0. 9) mm,the left celiac ganglia were larger than the right (t = 13. 635, P <0. 001). Conclusion Multi-detector CT can show the location, size, morphologic feature of the celiac ganglia. The left celiac ganglia had higher display rate than right but without statistical difference.%目的 探讨腹腔神经节多层螺旋CT(MDCT)的表现.资料与方法 回顾分析133例上腹部CT平扫和增强扫描无异常患者的CT资料,记录和测量腹腔神经节的位置、形态及大小.结果 左侧腹腔神经节124例显示,9例显示不清;右侧115例显示,18例显示不清,两侧显示率的差异无统计学意义(左侧,93.2%;右侧,86.5%;x2=3.339,P=0.068).双侧腹腔神经节位于腹腔干

  4. Advanced Gastric Cancer: Differentiation of Borrmann Type IV versus Borrmann Type III by Two-Phased Dynamic Multi-Detector Row CT with Use of the Water Filling Method

    Kim, Dae Jung; Yu, Jeong Sik; Lee, Sang Min; Kim, Joo Hee; Chung, Jae Joon; Kim, Ki Whang [Dept. of Radiology, Yonsei University College of Medicine, Gangnam Severance Hospital, Seoul (Korea, Republic of); Kang, Hae Youn [CHA Bundang Medical Center, CHA University, Seongnam (Korea, Republic of)


    To characterize Borrmann type IV from Borrmann type III advanced gastric cancer (AGC) by two-phased multi-detector row computed tomography (MDCT) using the water filling method. A total of 143 patients (pathologically confirmed Borrmann type III and IV - 100 and 43 patients), who underwent preoperative MDCT, were enrolled. Two radiologists, retrospectively and independently, determined tumor enhancement pattern using a 5-grade scale without clinical information. A weighted kappa test was applied for interobserver variability. The score of tumor enhancement pattern correlated with Borrmann type as determined by Spearman's correlation coefficient. The accuracy of differentiation of Borrmann type using MDCT was determined by receiver operating characteristic curves. Interobserver agreement (weighted kappa = 0.683) was substantial. The tumor enhancement pattern score showed a significant correlation with Borrmann type (reviewer 1, r = 0.591, p < 0.001; reviewer 2, r = 0.616, p < 0.001). The accuracy for differentiation of Borrmann type on MDCT was 0.86 (p < 0.001) in both reviewers. The sensitivity and specificity of the diagnosis of Borrmann type IV were 79% and 82% in reviewer 1, and 88% and 78% in reviewer 2, respectively. Dual-phased MDCT using the water filling method can differentiate between Borrmann type IV and III AGC with high accuracy.

  5. Gamma multi-detectors and nuclear structure studies: search for superdeformed structures in {sup 147}Gd and {sup 144}Gd isotopes using Crystal Castle; simulation calculations for EUROGAM multi-detector definition; Multidetecteurs gamma et etudes de structure nucleaire: recherche avec le Chateau de Cristal de structures superdeformees dans les isotopes {sup 147}Gd et {sup 144}Gd; calculs de simulation pour la definition du multidetecteur EUROGAM

    France, G. de


    Computer simulations have been used for the calculation of the new generation of 4 {pi}{gamma} multi-detectors (Castle Crystal) of EUROGAM system (phase I and II). Two superdeformed bands (I and II), comprising 16 and 13 transitions respectively, have been described for {sup 147}Gd nucleus during the {sup 122}Sn({sup 30}Si,5n) fusion-evaporation reaction in a 155 MeV bombardment energy. Dynamic inertia momentum similarities and gamma transition energy similarities have been observed between band I and {sup 148}Gd nucleus and between band II and {sup 146}Gd nucleus, respectively. These similarities can be related to a pseudo-spin symmetry. Calculations suggest the existence of an octupolar susceptibility in this mass region. {sup 144}Gd nucleus has been studied using {sup 120}Sn({sup 29}Si,5n) fusion-evaporation reaction in a 155 MeV bombardment energy and using {sup 100}Mo({sup 48}Ti,4n) reactions in a 200 MeV bombardment energy. {gamma}-{gamma} coincidences have revealed the existence of a 58 keV width valley in the matrix representation compatible with theoretical predictions. In spite of the evidence for about ten transitions during these experiments, no superdeformed structure has been demonstrated for {sup 144}Gd nucleus. (J.S.). 87 refs., 57 figs., 41 tabs.

  6. Value of multi-detector CT angiography in Takayasu arteritis%多排螺旋CT对多发性大动脉炎的诊断价值

    陈海雄; 胡秋根; 李景雷


    目的 探讨多排螺旋CT(MDCT)在多发性大动脉炎中的诊断价值。方法 回顾性分析32 例经临床确诊为大动脉炎患者的MDCT 资料及实验室检查,图像后处理方法包括多平面重建(MPR)、曲面重建(CPR)、最大密度投影(MIP)、容积再现(VR),实验室检查主要包括红细胞沉降率(ESR)和C 反应蛋白(CRP)。结果 按照Lupi-Herrea 分类法,Ⅰ型10 例,Ⅱ型9 例,Ⅲ型8 例,Ⅳ型5 例;共累及血管134 支,狭窄- 阻塞型112 支;扩张型8 支;混合型14 支。受累血管管壁最大厚度范围为1.3~8.6 mm(平均3.65±1.58),活动期管壁最大厚度约2.7~8.6 mm(平均5.24±1.59),明显大于非活动期1.3~6.0 mm (平均2.93±0.92)(P<0.05)。增强扫描活动期管壁强化8 例(80.0%),非活动期管壁轻度强化2 例(9.0%),非活动期管壁钙化 7 例(31.8%)。结论 MDCT 能准确判断多发性大动脉炎的分型、分期及病变范围,可作为其首选检查方法。%ObjectiveTo investigate the clinical value of multi-detector computed tomography(MDCT)in the diagnosis of Takayasu's arteritis.Methods MDCT, erythrocyte sedimentation rate(ESR)and C-reactive protein(CRP)levels of 32 patients with Takayasu’s arteritis were analyzed retrospectively. Image processing included multi-planar reformation(MPR), maximum intensity projection (MIP), and volume rendering reconstruction(VR).Results The patients were classified Lupi-Herrea type I(10), type II(9), type III(8) and type IV(5). Of 134 abnormal vessels, 112 were stenotic or occlusive, 8 were dilated and 14 were mixed. The vessel wall thickness was 1.3-8.6 mm(average 3.65±1.58 mm)with significantly(P<0.05)thicker walls in the active phase(2.7-8.6 mm)than that in the resting phase(1.3-6.0 mm). There was heterogeneous contrast enhancement of the vessel walls in the active phase(80.0%), mild enhancement(9.0%)and calcification (31.8%)in the resting

  7. Calcium score of small coronary calcifications on multidetector computed tomography

    Groen, J M; Kofoed, K F; Zacho, M;


    Multi detector computed tomography (MDCT) underestimates the coronary calcium score as compared to electron beam tomography (EBT). Therefore clinical risk stratification based on MDCT calcium scoring may be inaccurate. The aim of this study was to assess the feasibility of a new phantom which ena...

  8. Distant metastases and synchronous second primary tumors in patients with newly diagnosed oropharyngeal and hypopharyngeal carcinomas: evaluation of {sup 18}F-FDG PET and extended-field multi-detector row CT

    Ng, Shu-Hang; Ko, Sheung-Fat; Chin, Shu-Chyn [Chang Gung University, Department of Molecular Imaging Center and Diagnostic Radiology, Chang Gung Memorial Hospital, Linkou Medical Center, Taoyuan (China); Chan, Sheng-Chieh; Yen, Tzu-Chen [Chang Gung University, Department of Nuclear Medicine, Chang Gung Memorial Hospital, Linkou Medical Center, Taoyuan (China); Liao, Chun-Ta; Huang, Shiang-Fu [Chang Gung University, Department of Otorhinolaryngology, Chang Gung Memorial Hospital, Taoyuan (China); Chang, Joseph Tung-Chieh; Lin, Chin-Yu. [Chang Gung Memorial Hospital and Chang Gung University, Department of Radiation Oncology, Taoyuan (China); Wang, Hung-Ming [Chang Gung University, Department of Medical Oncology, Chang Gung Memorial Hospital, Taoyuan (China)


    Patients with oropharyngeal or hypopharyngeal squamous cell carcinoma (SCC) have a high risk of having distant metastases or second primary tumors. We prospectively evaluate the clinical usefulness of {sup 18}F-fluoro-2-deoxyglucose positron emission tomography ({sup 18}F-FDG PET), extended-field multi-detector computed tomography (MDCT), and their side-by-side visual correlation for the detection of distant malignancies in these two tumors at presentation. A total of 160 patients with SCC of the oropharynx (n = 74) or hypopharynx (n=86) underwent {sup 18}F-FDG PET and extended-field MDCT to detect distant metastases or second primary tumors. Suspected lesions were investigated by means of biopsy, clinical, or imaging follow-up. Twenty-six (16.3%) of our 160 patients were found to have distant malignancy. Diagnostic yields of {sup 18}F-FDG PET and MDCT were 12.5% and 8.1%, respectively. The sensitivity of {sup 18}F-FDG PET for detection of distant malignancies was 1.5-fold higher than that of MDCT (76.9% vs. 50.0%, P=0.039), while its specificity was slightly lower (94.0% vs. 97.8%, P=0.125). Side-by-side visual correlation of MDCT and {sup 18}F-FDG PET improved the sensitivity and specificity up to 80.8% and 98.5%, respectively, leading to alteration of treatment in 13.1% of patients. A significant difference in survival rates between its positive and negative results was observed. {sup 18}F-FDG PET and extended-field MDCT had acceptable diagnostic yields for detection of distant malignancies in untreated oropharyngeal and hypopharyngeal SCC. {sup 18}F-FDG PET was 1.5-fold more sensitive than MDCT, but had more false-positive findings. Their visual correlation improved the diagnostic accuracy, treatment planning, and prognosis prediction. (orig.)

  9. The measurement of position of retromandibular vein with multi-detector row helical CTA in relation to the mandibular angle plasty.%下颌角手术相关颌后静脉走行的CTA研究

    王燕; 华泽权; 刘文元; 李树华


    目的:应用CTA(血管造影术)影像测量颌后静脉与下颌角手术相关解剖,为避免手术中损伤颌后静脉提供指导.方法:选择30名正常成人下颌角及周围血管CTA扫描图像,应用ADW4.2图像处理软件测量颌后静脉距下颌角处颌骨各边缘的三维解剖位置.结果:颌后静脉距下颌角点的距离为(11.26±2.34) mm;在下颌角点上10 mm处距下颌骨后缘为(8.18±2.12) mm;在下颌角点上20 mm处距下颌骨后缘为(6.38±2.12) mm;在下颌角点上30 mm处距下颌骨后缘为(3.18±2.12) mm,在下颌角点上40 mm处距下颌骨后缘为(2.18±1.16) mm.结论:在下颌骨后缘手术时位置越高颌后静脉距下颌骨越近,手术越容易损伤颌后静脉;参照测量获得的解剖数据在下颌角成型手术中能避免损伤面前静脉及颌后静脉.%Objective: The aim of this study was to investigate the position and course of retromandibular vein using multi-detector row helical computed tomographic angiography (CTA)imaging and to relate the findings to performing the mandibular angle ptasty. Method: thirty of adulty human were selected for multi-detector row helical CTA measurement and ADW4.2 software analysis, according with a distance from the retromandibular vein to mandibular 10 mm urper the mandibular angletat 20 mm urper the mandibular angle,at 30 mm urper the mandibular angle, and at 40 mm urper the mandibular angle, retromandibular vein was examined. Result: the distance from the retromandibular vein to the mandibular angle is(11.26±2.34) 10 mm urper the mandibular angle is (8.18±2.12) 20 mm urper the mandibular angle is (6.38±2.12)mm,at 30 mm urper the mandibular angle is (3.18±2.12)mm,at 40 mm urper the mandibular angle is (2.18± 1.16)mm.Conclusion:The study is to provide further understanding of the retromandibular vein anatomy in relation to the design of the mandibuler angle plasty and to create clinical safety guidelines in order to avoid damaging

  10. Multi-Detector CT Findings of the Normal Appendix in Children: Evaluation of the Position, Diameter, and Presence or Absence of Intraluminal Gas

    Park, Woon Ju; Kim, Jong Chul [Dept. of Radiology, Chungnam National University College of Medicine, Daejeon (Korea, Republic of)


    To assess the usefulness of multi-detector CT (MDCT) with multiplanar reformations (MPR) for the evaluation of the position, diameter and presence or absence of intraluminal gas in the normal appendix in children. From 2007 to 2010, we retrospectively analyzed the MDCT images of normal appendices in 133 children, and evaluated the position, diameter, and presence or absence of intraluminal gas in the appendix. Among the 133 appendices, type I (postileal and medial paracecal position) was found in 64 children, type II (subcecal position) in 22, type III (retrocecal and retrocolic/laterocolic position) in 15, type IV (preileal and medial colic position) in 16, and type V (lower pelvic position) in 16 children. The mean diameter was 5.8 mm {+-} 1.2 (SD) (range; 3.2-8.7 mm). There was a high correlation between the appendiceal diameter and age (p = 0.000).There was no statistically significant difference in the appendiceal diameter between boys and girls (p = 0.470). Intraluminal gas was found in 115 appendices and there was no statistically significant correlation between the appendiceal diameter and intraluminal gas (p = 0.502). The MDCT with MPR was useful for the evaluation of the normal appendices in children. The procedure may be useful for the diagnosis of equivocal or unusual appendicitis in children.

  11. Comparison of ventilation/perfusion scintigraphy and multi-detector computerized tomography in diagnosis of asymptomatic pulmonary embolism after deep vein thrombosis

    Eflatun Yücedağ


    Full Text Available Objective: Pulmonary thromboembolism (PTE named due to migration of clots formed in systemic venous system to pulmonary vascular bed is a serious clinical table. After acute DVT, asymptomatic PTE is seen about 40-60% and this situation can not be discovered because of silent clinical course. In this study, we aimed to compare sensivity and spesifity of multi detector computerized tomography (MDCT, which is used extensively in recent years, with ventilation-perfusion (V/P scintigraphy which is used formerly for diagnosis of asymptomatic PTE developed after acute lower extremity DVT. Methods: The study was carried out 25 patients who were admitted to our clinic and treated for lower extremity acute DVT. Pregnants, and cases with recurrent DVT, presence of symptomatic PTE during admission, thrombosis extending to vena cava, and history of passed PTE were excluded from the study. DVTs in patients were diagnosed by color doppler, and confirmed by D-dimer test. After patients’s admission, V/P scintigraphy and MDCT were used to detects asymptomatic PTE at 1st and 8 th day of the admission. Results: D-dimer was measured as higher in 24 of 25 patients with asemptomatic PTE. Ten patients were diagnosed by MDCT. Development of asymptomatic PTE related to acute DVT was determined as 40%. Conclusion: In terms of diagnostic value, MDCT was found more useful than V/P scintigraphy.

  12. Sixty-four-slice computed tomography in surgical strategy of portal vein cavernous transformation

    Ming-Man Zhang; Cong-Lun Pu; Ying-Cun Li; Chun-Bao Guo


    AIM:To investigate the role of 64-slice computed tomography (CT) in portal vein cavernous transformation to determine surgical strategy.METHODS:The site of lesions and extent of collateral circulation in 12 pediatric cases of cavernous transformation of the portal vein with surgical treatment were analyzed.RESULTS:Eleven of 12 children had esophageal vari-ces and were treated with lower esophageal and gastric devascularization and splenectomy,and the other case was only treated with splenectomy.There were eight cases with spontaneous spleen/stomach-renal shunt,four with Retzius vein opening,which was reserved during surgery.Three cases of lesions involving the intrahepatic portal vein (PV) were treated with livingdonor liver transplantation.One patient died from PV thrombosis after liver transplantation,and the rest had no significant complications.CONCLUSION:The PV,its branches and collateral circulation were clearly seen by 64-slice spiral CT angi-ography,which helped with preoperative surgical planning.

  13. Pulmonary Findings on Computed Tomography in Asymptomatic Total Joint Arthroplasty Patients.

    Vigdorchik, Jonathan M; Riesgo, Aldo M; Lincoln, Denis; Markel, David C


    An increase in the diagnosis of pulmonary embolus (PE) in the early postoperative period has been attributed to the use of multidetector 64-slice computed tomographic (CT) scans. It was suspected that this finding was the result of marrow or fat emboli that are commonly associated with arthroplasty rather than a true venous thromboembolic phenomenon. The purpose of this study was to determine the baseline pulmonary findings in asymptomatic patients after total joint arthroplasty (TJA). Over a 1-year period, an institutional review board-approved prospective study of 20 asymptomatic patients using a multidetector 64-slice CT scanner was performed. Overall, 15 TKAs and 5 total hip arthroplasties were included for analysis. All of the CT scans were negative for PE. There were no signs of microemboli or fat emboli on any scan. No patient went on to develop a PE at 2 years postoperatively. Despite the fact that emboli are created during TJA, if emboli are seen on a CT scan postoperatively, they should be assumed to be real events with clinical sequelae. If pulmonary symptoms develop postoperatively, they should not simply be assumed to be the result of fat or marrow embolism.

  14. Enhancement patterns of pancreatic adenocarcinoma on conventional dynamic multi-detector row CT: Correlation with angiogenesis and fibrosis

    Yuki Hattori; Toshifumi Gabata; Osamu Matsui; Kentaro Mochizuki; Hirohisa Kitagawa; Masato Kayahara; Tetsuo Ohta; Yasuni Nakanuma


    AIM: To evaluate retrospectively the correlation between enhancement patterns on dynamic computed tomography (CT) and angiogenesis and fibrosis in pancreatic adenocarcinoma.METHODS: Twenty-three patients with pancreatic adenocarcinoma underwent dynamic CT and tumor resection. In addition to the absolute and relative enhanced value that was calculated by subtracting the attenuation value on pre-contrast from those on contrast-enhanced CT in each phase, we defined one parameter, "tumor-aorta enhancement ratio", which was calculated by dividing enhancement of pancreatic cancer by enhancement of abdominal aorta in each phase. These enhancement patterns were correlated with the level of vascular endothelial growth factor (VEGF), microvessel density (MVD), and extent of fibrosis.RESULTS: The absolute enhanced value in the arterial phase correlated with the level of VEGF and MVD (P = 0.047, P = 0.001). The relative enhanced value in arterial phase and tumor-aorta enhancement ratio (arterial) correlated with MVD (P = 0.003, P = 0.022). Tumor-aorta enhancement ratio (arterial) correlated negatively with the extent of fibrosis (P = 0.004). The tumors with greater MVD and higher expression of VEGF tended to show high enhancement in the arterial dominant phase. On the other hand, the tumors with a larger amount of fibrosis showed a negative correlation with the grade of enhancement during the arterial phase.CONCLUSION: Enhancement patterns on dynamic CT correlated with angiogenesis and may be modified by the extent of fibrosis.

  15. Liver tumour segmentation using contrast-enhanced multi-detector CT data: performance benchmarking of three semiautomated methods

    Zhou, Jia-Yin [National University of Singapore, Department of Diagnostic Radiology, Yong Loo Lin School of Medicine, Singapore (Singapore); Agency for Science, Technology and Research, Institute for Infocomm Research, Singapore (Singapore); Wong, Damon W.K.; Tian, Qi; Xiong, Wei; Liu, Jimmy J. [Agency for Science, Technology and Research, Institute for Infocomm Research, Singapore (Singapore); Ding, Feng; Venkatesh, Sudhakar K.; Qi, Ying-Yi [National University of Singapore, Department of Diagnostic Radiology, Yong Loo Lin School of Medicine, Singapore (Singapore); Leow, Wee-Kheng [National University of Singapore, School of Computing, Singapore (Singapore)


    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.)

  16. Transcatheter aortic valve implantation: role of multi-detector row computed tomography to evaluate prosthesis positioning and deployment in relation to valve function.

    Delgado, V.; Ng, A.C.; Veire, N.R. van de; Kley, F. van der; Schuijf, J.D.; Tops, L.F.; Weger, A. de; Tavilla, G.; Roos, A. de; Kroft, L.J.; Schalij, M.J.; Bax, J.J.


    AIMS: Aortic regurgitation after transcatheter aortic valve implantation (TAVI) is one of the most frequent complications. However, the underlying mechanisms of this complication remain unclear. The present evaluation studied the anatomic and morphological features of the aortic valve annulus that m

  17. Myocardial perfusion at rest in patients with Diabetes Mellitus Type 1 compared with healthy controls assessed with Multi Detector Computed Tomography

    Byrne, Christina; Jensen, Tonny; Hjortkjær, Henrik Øder;


    AIM: Type 1 diabetes mellitus (T1DM) is associated with an increased risk of ischemic heart disease (IHD). The relative contribution of structural and functional abnormalities of the coronary circulation determining clinically manifested IHD remains unknown. The aim of this study was to assess......AD-ratio) was 18% higher in T1DM patients than controls (0.13 vs. 0.11, psegments. In a multiple regression analysis including diabetes, sex, age, cardiovascular risk factors, heart rate, calcium score and coronary stenosis >50%, Myo...

  18. Comprehensive assessment of a post-coronary bypass graft patient with cardiovascular magnetic resonance imaging and multi-detector computed tomography

    Pairoj Rerkpattanapipat; Patcharee Paijitprapaporn; Suthipong Jongjirasiri; Jiraporn Laothamatas; Nithi Mahanonda


    Coronary bypass graft surgery (CABG) is a revascularization procedure which reduces myocardial ischemia and cardiovascular morbidity and mortality in selected patients; however, up to 40% of saphanous vein grafts may degenerate over 10 years. Although coronary angiography is the gold standard to detect graft patency and native vessel disease, sometimes it is difficult to locate the grafts resulting in increased exposure to radiation and contrast administration. This case highlights the utility of cardiac computerized tomography and magnetic resonance imaging to provide comprehensive noninvasive assessment in a patient post CABG.

  19. Evaluation to Obtain the Image According to the Spatial Domain Filtering of Various Convolution Kernels in the Multi-Detector Row Computed Tomography

    Lee, Hoo Min [Dept. of Radiologic Technology, Dongnam Health College, Suwon (Korea, Republic of); Yoo, Beong Gyu [Dept. of Radiologic Technology, Wonkwang Health Science College, Iksan (Korea, Republic of); Kweon, Dae Cheol [Dept. of Radiology, Seoul National University, Seoul (Korea, Republic of)


    Our objective was to evaluate the image of spatial domain filtering as an alternative to additional image reconstruction using different kernels in MDCT. Derived from thin collimated source images were generated using water phantom and abdomen B10(very smooth), B20(smooth), B30(medium smooth), B40 (medium), B50(medium sharp), B60(sharp), B70(very sharp) and B80(ultra sharp) kernels. MTF and spatial resolution measured with various convolution kernels. Quantitative CT attenuation coefficient and noise measurements provided comparable HU(Hounsfield) units in this respect. CT attenuation coefficient(mean HU) values in the water were values in the water were 1.1{approx}1.8 HU, air(-998{approx}-1000 HU) and noise in the water(5.4{approx}44.8 HU), air(3.6{approx}31.4 HU). In the abdominal fat a CT attenuation coefficient(-2.2{approx}0.8 HU) and noise(10.1{approx}82.4 HU) was measured. In the abdominal was CT attenuation coefficient(53.3{approx}54.3 HU) and noise(10.4{approx}70.7 HU) in the muscle and in the liver parenchyma of CT attenuation coefficient(60.4{approx}62.2 HU) and noise (7.6{approx}63.8 HU) in the liver parenchyma. Image reconstructed with a convolution kernel led to an increase in noise, whereas the results for CT attenuation coefficient were comparable. Image scanned with a high convolution kernel(B80) led to an increase in noise, whereas the results for CT attenuation coefficient were comparable. Image medications of image sharpness and noise eliminate the need for reconstruction using different kernels in the future. Adjusting CT various kernels, which should be adjusted to take into account the kernels of the CT undergoing the examination, may control CT images increase the diagnostic accuracy.

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

    Andersen, Kjel [Institute of Diagnostic Radiology, University Hospital Duesseldorf (Germany)]. E-mail:; 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)


    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.

  1. National Survey of Radiation Dose and Image Quality in Adult CT Head Scans in Taiwan.

    Chung-Jung Lin

    Full Text Available The purpose of the present study was to evaluate the influence of different variables on radiation dose and image quality based on a national database.Taiwan's Ministry of Health and Welfare requested all radiology departments to complete a questionnaire for each of their CT scanners. Information gathered included all scanning parameters for CT head scans. For the present analysis, CT machines were divided into three subgroups: single slice CT (Group A; multi-detector CT (MDCT with 2-64 slices (Group B; and MDCT with more than 64 slices (Group C. Correlations between computed tomography dose index (CTDI and signal-to-noise ratio (SNR with cumulated tube rotation number (CTW(n and cumulated tube rotation time (CTW(s, and sub group analyses of CTDI and SNR across the three groups were performed.CTDI values demonstrated a weak correlation (r = 0.33 with CTW(n in Group A. SNR values demonstrated a weak negative correlation (r = -0.46 with CTW(n in Group C. MDCT with higher slice numbers used more tube potential resulting in higher effective doses. There were both significantly lower CTDI and SNR values in helical mode than in axial mode in Group B, but not Group C.CTW(n and CTW(s did not influence radiation output. Helical mode is more often used in MDCT and results in both lower CTDI and SNR compared to axial mode in MDCT with less than 64 slices.

  2. Multi-detector CT perfusion

    Ashraf M. Enite


    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.

  3. Study on motion artifacts in coronary arteries with an anthropomorphic moving heart phantom on an ECG-gated multidetector computed tomography unit

    Greuter, MJW; Dorgelo, J; Tukker, WGJ; Oudkerk, M


    Acquisition time plays a key role in the quality of cardiac multi-detector computed tomography (MDCT) and is directly related to the rotation time of the scanner. The purpose of this study is to examine the influence of heart rate and a multisector reconstruction algorithm on the image quality of co

  4. The Value of Multi-detector row CT in Gastroenteropathy and Application of Contrast Agents%MDCT在胃肠道检查中的价值及对比剂的应用

    鲁桂青; 陈克敏; 刘林祥


    胃肠道疾患在过去以传统的检查方法 (主要为消化道钡剂透视及纤维内窥镜)为主,随着多层螺旋CT(multi-detector row CT,MDCT)的快速发展以及各种不同腔内对比剂的研究与应用,CT对胃肠道的检查价值显著提高。

  5. Comparison between multi-detector row CT angiography and Doppler ultrasound on detecting carotid artery wall thickness%多层螺旋CT与Doppler超声对颈动脉壁层厚度的对比性研究

    赵刚; 查云飞; 王弘; 洪玮; 邱晓明; 王珍; 肖友梅


    Objective To explore the relationship and consistency between multi-detector row computed tomography angiography (MDCTA) and color Doppler ultrasound (CD-US) in measuring carotid artery wall thickness (CAWT) and intima-media thickness (IMT). Methods CAWT and IMT of 38 subjects were measured using MDCTA and CD-US, respectively. Linear correlation analysis was performed to analyze the correlation between the results from CAWT and IMT,and Bland-Altman statistics was employed to analyze the consistency between them. Results The IMT value measured by CD-US was (0.85+0.16) mm, and the CAWT value measured by MDCTA was (0.87.± 0.18) mm (P > 0.05), and there was a high degree of correlation between them (correlation coefficient was 0.958,P< 0.01). An excellent consistency between CAWT and IMT was found by Bland-Altman plot, with a bias of 0.026 mm and the limit of consistency from -0.023 to 0.075. Conclusions There were significant correlation and consistency between MDCTA and CD-US in detecting CAWT and IMT. As a more objective and comprehensive new method, MDCTA can replace CD-US in the evaluation of early carotid atherosclerosis.%目的:探讨多层螺旋CT血管造影(MDCTA)和彩色多普勒超声(CD-US)在检测颈总动脉壁厚度(CAWT)和颈总动脉内膜-中层厚度(IMT)中的相关性和一致性.方法:应用MDCTA和CD-US分别对38例受试者颈总动脉的CAWT和IMT进行检测,用Pearson直线相关分析比较CAWT和IMT的相关性,用Bland-Altman分析比较两者的一致性.结果:MDCTA测量的颈总动脉CAWT为(0.87±0.18)mm,CD-US测量的颈总动脉IMT为(0.85±0.16)mm,两者比较无统计学差异,有高度相关性,相关系数为0.958,P<0.01,Bland-Altman分析两者间存在良好一致性,偏倚为0.026 mm,一致性界限为-0.023 ~ 0.075.结论:MDCTA和CD-US在检测颈总动脉CAWT和IMT时存在良好的相关性和一致性,MDCTA可以替代CD-US,作为一种评价颈动脉早期粥样硬化的更加客观全面的新方法.

  6. Retrospectively ECG-gated multi-detector row CT of the chest: does ECG-gating improve three-dimensional visualization of the bronchial tree?

    Schertler, T.; Wildermuth, S.; Willmann, J.K.; Crook, D.W.; Marincek, B.; Boehm, T. [Dept. Medical Radiology, Inst. of Diagnostic Radiology, Univ. Hospital Zurich (Switzerland)


    Purpose: To determine the impact of retrospectively ECG-gated multi-detector row CT (MDCT) on three-dimensional (3D) visualization of the bronchial tree and virtual bronchoscopy (VB) as compared to non-ECG-gated data acquisition. Materials and Methods: Contrast-enhanced retrospectively ECG-gated and non-ECG-gated MDCT of the chest was performed in 25 consecutive patients referred for assessment of coronary artery bypass grafts and pathology of the ascending aorta. ECG-gated MDCT data were reconstructed in diastole using an absolute reverse delay of -400 msec in all patients. In 10 patients additional reconstructions at -200 msec, -300 msec, and -500 msec prior to the R-wave were performed. Shaded surface display (SSD) and virtual bronchoscopy (VB) for visualization of the bronchial segments was performed with ECG-gated and non-ECG-gated MDCT data. The visualization of the bronchial tree underwent blinded scoring. Effective radiation dose and signal-to-noise ratio (SNR) for both techniques were compared. Results: There was no significant difference in visualizing single bronchial segments using ECG-gated compared to non-ECG-gated MDCT data. However, the total sum of scores for all bronchial segments visualized with non-ECG-gated MDCT was significantly higher compared to ECG-gated MDCT (P<0.05). The summary scores for visualization of bronchial segments for different diastolic reconstructions did not differ significantly. The effective radiation dose and the SNR were significantly higher with the ECG-gated acquisition technique (P<0.05). Conclusion: The bronchial tree is significantly better visualized when using non-ECG-gated MDCT compared to ECG-gated MDCT. Additionally, non-ECG-gated techniques require less radiation exposure. Thus, the current retrospective ECG-gating technique does not provide any additional benefit for 3D visualization of the bronchial tree and VB. (orig.) [German] Ziel: Untersuchung des Einflusses der retrospektiven EKG-Synchronisierung auf

  7. Study of superdeformation in {sup 151,152}Tb isotopes using Eurogam multi-detector; Etude de la superdeformation dans les isotopes {sup 151,152}Tb a l`aide du multidetecteur Eurogam

    Kharraja, E.B.


    The aim of this work is the study of {sup 151}Tb and {sup 152}Tb nuclei submitted to increasing speeds using the EUROGAM (phase I) multi-detector. The production of high angular momentum excited nuclei is obtained during {sup 130}Te({sup 27}Al,xn) fusion-evaporation reaction with a 154 MeV bombardment energy. For {sup 151}Tb nucleus, the diagram of high spin normal deformation levels is first determined to allow the analysis of bonds between SD structures and normally deformed states. In addition to the two SD bands already described for {sup 151}Tb nucleus, 8 new SD bands are described (6 for {sup 151}Tb nucleus and 2 for {sup 152}Tb nucleus) using triple and quadruple events analysis. The SD structure analysis gives important informations about nuclear superdeformation in this mass region, in particular about SD bands de-excitation, intrinsic configuration in the second potential well, and gamma transition energy degeneration between twin SD bands. A detailed description of EUROGAM 4{pi}{gamma} multi-detector (phase I and II), which comprises 42 Ge detectors with Compton suppression, is given. (J.S.). 98 refs., 100 figs., 22 tabs.

  8. Diagnostic yield and complications of transthoracic computed tomography-guided biopsies

    Vagn-Hansen, Chris Aksel; Pedersen, Malene Roland Vils; Rafaelsen, Søren Rafael


    INTRODUCTION: The widespread use of computed tomography (CT) improves detection of pulmonary lesions, which are not only detected at an increased rate but also at a smaller size. CT-guided lung biopsies are now more frequently used than fluoroscopy-guided lung biopsies. The main aim of the present...... paper was to investigate the outcome and complications of the biopsies. METHODS: We retrospectively collected the results and information from 520 CT-guided thorax biopsies. All biopsies were performed with CT-guided “beam-through” technique, using a 64-slice CT scanner. RESULTS: In 86% of the biopsies......, the tissue material was found to be sufficient. In 32% of the biopsies, a complication arose, mostly pneumothorax (30%), but chest drainage was needed in only 15% of the 520 cases. Patients with more than ten cigarette pack-years had a complication risk that was twice as high at that of patients with fewer...


    M. Kasemann

    Overview In autumn the main focus was to process and handle CRAFT data and to perform the Summer08 MC production. The operational aspects were well covered by regular Computing Shifts, experts on duty and Computing Run Coordination. At the Computing Resource Board (CRB) in October a model to account for service work at Tier 2s was approved. The computing resources for 2009 were reviewed for presentation at the C-RRB. The quarterly resource monitoring is continuing. Facilities/Infrastructure operations Operations during CRAFT data taking ran fine. This proved to be a very valuable experience for T0 workflows and operations. The transfers of custodial data to most T1s went smoothly. A first round of reprocessing started at the Tier-1 centers end of November; it will take about two weeks. The Computing Shifts procedure was tested full scale during this period and proved to be very efficient: 30 Computing Shifts Persons (CSP) and 10 Computing Resources Coordinators (CRC). The shift program for the shut down w...


    M. Kasemann

    Overview During the past three months activities were focused on data operations, testing and re-enforcing shift and operational procedures for data production and transfer, MC production and on user support. Planning of the computing resources in view of the new LHC calendar in ongoing. Two new task forces were created for supporting the integration work: Site Commissioning, which develops tools helping distributed sites to monitor job and data workflows, and Analysis Support, collecting the user experience and feedback during analysis activities and developing tools to increase efficiency. The development plan for DMWM for 2009/2011 was developed at the beginning of the year, based on the requirements from the Physics, Computing and Offline groups (see Offline section). The Computing management meeting at FermiLab on February 19th and 20th was an excellent opportunity discussing the impact and for addressing issues and solutions to the main challenges facing CMS computing. The lack of manpower is particul...


    I. Fisk


    Introduction CMS distributed computing system performed well during the 2011 start-up. The events in 2011 have more pile-up and are more complex than last year; this results in longer reconstruction times and harder events to simulate. Significant increases in computing capacity were delivered in April for all computing tiers, and the utilisation and load is close to the planning predictions. All computing centre tiers performed their expected functionalities. Heavy-Ion Programme The CMS Heavy-Ion Programme had a very strong showing at the Quark Matter conference. A large number of analyses were shown. The dedicated heavy-ion reconstruction facility at the Vanderbilt Tier-2 is still involved in some commissioning activities, but is available for processing and analysis. Facilities and Infrastructure Operations Facility and Infrastructure operations have been active with operations and several important deployment tasks. Facilities participated in the testing and deployment of WMAgent and WorkQueue+Request...


    P. McBride

    The Computing Project is preparing for a busy year where the primary emphasis of the project moves towards steady operations. Following the very successful completion of Computing Software and Analysis challenge, CSA06, last fall, we have reorganized and established four groups in computing area: Commissioning, User Support, Facility/Infrastructure Operations and Data Operations. These groups work closely together with groups from the Offline Project in planning for data processing and operations. Monte Carlo production has continued since CSA06, with about 30M events produced each month to be used for HLT studies and physics validation. Monte Carlo production will continue throughout the year in the preparation of large samples for physics and detector studies ramping to 50 M events/month for CSA07. Commissioning of the full CMS computing system is a major goal for 2007. Site monitoring is an important commissioning component and work is ongoing to devise CMS specific tests to be included in Service Availa...


    I. Fisk


    Computing activity had ramped down after the completion of the reprocessing of the 2012 data and parked data, but is increasing with new simulation samples for analysis and upgrade studies. Much of the Computing effort is currently involved in activities to improve the computing system in preparation for 2015. Operations Office Since the beginning of 2013, the Computing Operations team successfully re-processed the 2012 data in record time, not only by using opportunistic resources like the San Diego Supercomputer Center which was accessible, to re-process the primary datasets HTMHT and MultiJet in Run2012D much earlier than planned. The Heavy-Ion data-taking period was successfully concluded in February collecting almost 500 T. Figure 3: Number of events per month (data) In LS1, our emphasis is to increase efficiency and flexibility of the infrastructure and operation. Computing Operations is working on separating disk and tape at the Tier-1 sites and the full implementation of the xrootd federation ...

  14. Computer

    Atkinson, Paul


    The pixelated rectangle we spend most of our day staring at in silence is not the television as many long feared, but the computer-the ubiquitous portal of work and personal lives. At this point, the computer is almost so common we don't notice it in our view. It's difficult to envision that not that long ago it was a gigantic, room-sized structure only to be accessed by a few inspiring as much awe and respect as fear and mystery. Now that the machine has decreased in size and increased in popular use, the computer has become a prosaic appliance, little-more noted than a toaster. These dramati


    I. Fisk


    Introduction It has been a very active quarter in Computing with interesting progress in all areas. The activity level at the computing facilities, driven by both organised processing from data operations and user analysis, has been steadily increasing. The large-scale production of simulated events that has been progressing throughout the fall is wrapping-up and reprocessing with pile-up will continue. A large reprocessing of all the proton-proton data has just been released and another will follow shortly. The number of analysis jobs by users each day, that was already hitting the computing model expectations at the time of ICHEP, is now 33% higher. We are expecting a busy holiday break to ensure samples are ready in time for the winter conferences. Heavy Ion An activity that is still in progress is computing for the heavy-ion program. The heavy-ion events are collected without zero suppression, so the event size is much large at roughly 11 MB per event of RAW. The central collisions are more complex and...


    M. Kasemann P. McBride Edited by M-C. Sawley with contributions from: P. Kreuzer D. Bonacorsi S. Belforte F. Wuerthwein L. Bauerdick K. Lassila-Perini M-C. Sawley

    Introduction More than seventy CMS collaborators attended the Computing and Offline Workshop in San Diego, California, April 20-24th to discuss the state of readiness of software and computing for collisions. Focus and priority were given to preparations for data taking and providing room for ample dialog between groups involved in Commissioning, Data Operations, Analysis and MC Production. Throughout the workshop, aspects of software, operating procedures and issues addressing all parts of the computing model were discussed. Plans for the CMS participation in STEP’09, the combined scale testing for all four experiments due in June 2009, were refined. The article in CMS Times by Frank Wuerthwein gave a good recap of the highly collaborative atmosphere of the workshop. Many thanks to UCSD and to the organizers for taking care of this workshop, which resulted in a long list of action items and was definitely a success. A considerable amount of effort and care is invested in the estimate of the comput...

  17. Multi-scale analysis of lung computed tomography images

    Gori, I; Fantacci, M E; Preite Martinez, A; Retico, A; De Mitri, I; Donadio, S; Fulcheri, C


    A computer-aided detection (CAD) system for the identification of lung internal nodules in low-dose multi-detector helical Computed Tomography (CT) images was developed in the framework of the MAGIC-5 project. The three modules of our lung CAD system, a segmentation algorithm for lung internal region identification, a multi-scale dot-enhancement filter for nodule candidate selection and a multi-scale neural technique for false positive finding reduction, are described. The results obtained on a dataset of low-dose and thin-slice CT scans are shown in terms of free response receiver operating characteristic (FROC) curves and discussed.


    I. Fisk


    Introduction It has been a very active quarter in Computing with interesting progress in all areas. The activity level at the computing facilities, driven by both organised processing from data operations and user analysis, has been steadily increasing. The large-scale production of simulated events that has been progressing throughout the fall is wrapping-up and reprocessing with pile-up will continue. A large reprocessing of all the proton-proton data has just been released and another will follow shortly. The number of analysis jobs by users each day, that was already hitting the computing model expectations at the time of ICHEP, is now 33% higher. We are expecting a busy holiday break to ensure samples are ready in time for the winter conferences. Heavy Ion The Tier 0 infrastructure was able to repack and promptly reconstruct heavy-ion collision data. Two copies were made of the data at CERN using a large CASTOR disk pool, and the core physics sample was replicated ...


    M. Kasemann

    Introduction More than seventy CMS collaborators attended the Computing and Offline Workshop in San Diego, California, April 20-24th to discuss the state of readiness of software and computing for collisions. Focus and priority were given to preparations for data taking and providing room for ample dialog between groups involved in Commissioning, Data Operations, Analysis and MC Production. Throughout the workshop, aspects of software, operating procedures and issues addressing all parts of the computing model were discussed. Plans for the CMS participation in STEP’09, the combined scale testing for all four experiments due in June 2009, were refined. The article in CMS Times by Frank Wuerthwein gave a good recap of the highly collaborative atmosphere of the workshop. Many thanks to UCSD and to the organizers for taking care of this workshop, which resulted in a long list of action items and was definitely a success. A considerable amount of effort and care is invested in the estimate of the co...


    I. Fisk


    Introduction Computing continued with a high level of activity over the winter in preparation for conferences and the start of the 2012 run. 2012 brings new challenges with a new energy, more complex events, and the need to make the best use of the available time before the Long Shutdown. We expect to be resource constrained on all tiers of the computing system in 2012 and are working to ensure the high-priority goals of CMS are not impacted. Heavy ions After a successful 2011 heavy-ion run, the programme is moving to analysis. During the run, the CAF resources were well used for prompt analysis. Since then in 2012 on average 200 job slots have been used continuously at Vanderbilt for analysis workflows. Operations Office As of 2012, the Computing Project emphasis has moved from commissioning to operation of the various systems. This is reflected in the new organisation structure where the Facilities and Data Operations tasks have been merged into a common Operations Office, which now covers everything ...


    M. Kasemann

    Introduction During the past six months, Computing participated in the STEP09 exercise, had a major involvement in the October exercise and has been working with CMS sites on improving open issues relevant for data taking. At the same time operations for MC production, real data reconstruction and re-reconstructions and data transfers at large scales were performed. STEP09 was successfully conducted in June as a joint exercise with ATLAS and the other experiments. It gave good indication about the readiness of the WLCG infrastructure with the two major LHC experiments stressing the reading, writing and processing of physics data. The October Exercise, in contrast, was conducted as an all-CMS exercise, where Physics, Computing and Offline worked on a common plan to exercise all steps to efficiently access and analyze data. As one of the major results, the CMS Tier-2s demonstrated to be fully capable for performing data analysis. In recent weeks, efforts were devoted to CMS Computing readiness. All th...


    P. McBride

    It has been a very active year for the computing project with strong contributions from members of the global community. The project has focused on site preparation and Monte Carlo production. The operations group has begun processing data from P5 as part of the global data commissioning. Improvements in transfer rates and site availability have been seen as computing sites across the globe prepare for large scale production and analysis as part of CSA07. Preparations for the upcoming Computing Software and Analysis Challenge CSA07 are progressing. Ian Fisk and Neil Geddes have been appointed as coordinators for the challenge. CSA07 will include production tests of the Tier-0 production system, reprocessing at the Tier-1 sites and Monte Carlo production at the Tier-2 sites. At the same time there will be a large analysis exercise at the Tier-2 centres. Pre-production simulation of the Monte Carlo events for the challenge is beginning. Scale tests of the Tier-0 will begin in mid-July and the challenge it...


    I. Fisk


    Introduction The first data taking period of November produced a first scientific paper, and this is a very satisfactory step for Computing. It also gave the invaluable opportunity to learn and debrief from this first, intense period, and make the necessary adaptations. The alarm procedures between different groups (DAQ, Physics, T0 processing, Alignment/calibration, T1 and T2 communications) have been reinforced. A major effort has also been invested into remodeling and optimizing operator tasks in all activities in Computing, in parallel with the recruitment of new Cat A operators. The teams are being completed and by mid year the new tasks will have been assigned. CRB (Computing Resource Board) The Board met twice since last CMS week. In December it reviewed the experience of the November data-taking period and could measure the positive improvements made for the site readiness. It also reviewed the policy under which Tier-2 are associated with Physics Groups. Such associations are decided twice per ye...


    M. Kasemann

    CCRC’08 challenges and CSA08 During the February campaign of the Common Computing readiness challenges (CCRC’08), the CMS computing team had achieved very good results. The link between the detector site and the Tier0 was tested by gradually increasing the number of parallel transfer streams well beyond the target. Tests covered the global robustness at the Tier0, processing a massive number of very large files and with a high writing speed to tapes.  Other tests covered the links between the different Tiers of the distributed infrastructure and the pre-staging and reprocessing capacity of the Tier1’s: response time, data transfer rate and success rate for Tape to Buffer staging of files kept exclusively on Tape were measured. In all cases, coordination with the sites was efficient and no serious problem was found. These successful preparations prepared the ground for the second phase of the CCRC’08 campaign, in May. The Computing Software and Analysis challen...

  5. Correlation of radiation dose and heart rate in dual-source computed tomography coronary angiography

    Laspas, Fotios; Roussakis, Arkadios; Kritikos, Nikolaos; Efthimiadou, Roxani; Kehagias, Dimitrios; Andreou, John (CT and MRI Dept., Hygeia Hospital, Athens (Greece)), e-mail:; Tsantioti, Dimitra (Statistician, Hygeia Hospital, Athens (Greece))


    Background: Computed tomography coronary angiography (CTCA) has been widely used since the introduction of 64-slice scanners and dual-source CT technology, but the relatively high radiation dose remains a major concern. Purpose: To evaluate the relationship between radiation exposure and heart rate (HR), in dual-source CTCA. Material and Methods: Data from 218 CTCA examinations, performed with a dual-source 64-slices scanner, were statistically evaluated. Effective radiation dose, expressed in mSv, was calculated as the product of the dose-length product (DLP) times a conversion coefficient for the chest (mSv = DLPx0.017). Heart rate range and mean heart rate, expressed in beats per minute (bpm) of each individual during CTCA, were also provided by the system. Statistical analysis of effective dose and heart rate data was performed by using Pearson correlation coefficient and two-sample t-test. Results: Mean HR and effective dose were found to have a borderline positive relationship. Individuals with a mean HR >65 bpm observed to receive a statistically significant higher effective dose as compared to those with a mean HR =65 bpm. Moreover, a strong correlation between effective dose and variability of HR of more than 20 bpm was observed. Conclusion: Dual-source CT scanners are considered to have the capability to provide diagnostic examinations even with high HR and arrhythmias. However, it is desirable to keep the mean heart rate below 65 bpm and heart rate fluctuation less than 20 bpm in order to reduce the radiation exposure


    I. Fisk


    Computing operation has been lower as the Run 1 samples are completing and smaller samples for upgrades and preparations are ramping up. Much of the computing activity is focusing on preparations for Run 2 and improvements in data access and flexibility of using resources. Operations Office Data processing was slow in the second half of 2013 with only the legacy re-reconstruction pass of 2011 data being processed at the sites.   Figure 1: MC production and processing was more in demand with a peak of over 750 Million GEN-SIM events in a single month.   Figure 2: The transfer system worked reliably and efficiently and transferred on average close to 520 TB per week with peaks at close to 1.2 PB.   Figure 3: The volume of data moved between CMS sites in the last six months   The tape utilisation was a focus for the operation teams with frequent deletion campaigns from deprecated 7 TeV MC GEN-SIM samples to INVALID datasets, which could be cleaned up...


    I. Fisk


      Introduction Computing activity has been running at a sustained, high rate as we collect data at high luminosity, process simulation, and begin to process the parked data. The system is functional, though a number of improvements are planned during LS1. Many of the changes will impact users, we hope only in positive ways. We are trying to improve the distributed analysis tools as well as the ability to access more data samples more transparently.  Operations Office Figure 2: Number of events per month, for 2012 Since the June CMS Week, Computing Operations teams successfully completed data re-reconstruction passes and finished the CMSSW_53X MC campaign with over three billion events available in AOD format. Recorded data was successfully processed in parallel, exceeding 1.2 billion raw physics events per month for the first time in October 2012 due to the increase in data-parking rate. In parallel, large efforts were dedicated to WMAgent development and integrati...


    Matthias Kasemann

    Overview The main focus during the summer was to handle data coming from the detector and to perform Monte Carlo production. The lessons learned during the CCRC and CSA08 challenges in May were addressed by dedicated PADA campaigns lead by the Integration team. Big improvements were achieved in the stability and reliability of the CMS Tier1 and Tier2 centres by regular and systematic follow-up of faults and errors with the help of the Savannah bug tracking system. In preparation for data taking the roles of a Computing Run Coordinator and regular computing shifts monitoring the services and infrastructure as well as interfacing to the data operations tasks are being defined. The shift plan until the end of 2008 is being put together. User support worked on documentation and organized several training sessions. The ECoM task force delivered the report on “Use Cases for Start-up of pp Data-Taking” with recommendations and a set of tests to be performed for trigger rates much higher than the ...


    M. Kasemann

    Introduction A large fraction of the effort was focused during the last period into the preparation and monitoring of the February tests of Common VO Computing Readiness Challenge 08. CCRC08 is being run by the WLCG collaboration in two phases, between the centres and all experiments. The February test is dedicated to functionality tests, while the May challenge will consist of running at all centres and with full workflows. For this first period, a number of functionality checks of the computing power, data repositories and archives as well as network links are planned. This will help assess the reliability of the systems under a variety of loads, and identifying possible bottlenecks. Many tests are scheduled together with other VOs, allowing the full scale stress test. The data rates (writing, accessing and transfer¬ring) are being checked under a variety of loads and operating conditions, as well as the reliability and transfer rates of the links between Tier-0 and Tier-1s. In addition, the capa...


    Contributions from I. Fisk


    Introduction The start of the 2012 run has been busy for Computing. We have reconstructed, archived, and served a larger sample of new data than in 2011, and we are in the process of producing an even larger new sample of simulations at 8 TeV. The running conditions and system performance are largely what was anticipated in the plan, thanks to the hard work and preparation of many people. Heavy ions Heavy Ions has been actively analysing data and preparing for conferences.  Operations Office Figure 6: Transfers from all sites in the last 90 days For ICHEP and the Upgrade efforts, we needed to produce and process record amounts of MC samples while supporting the very successful data-taking. This was a large burden, especially on the team members. Nevertheless the last three months were very successful and the total output was phenomenal, thanks to our dedicated site admins who keep the sites operational and the computing project members who spend countless hours nursing the...


    P. MacBride

    The Computing Software and Analysis Challenge CSA07 has been the main focus of the Computing Project for the past few months. Activities began over the summer with the preparation of the Monte Carlo data sets for the challenge and tests of the new production system at the Tier-0 at CERN. The pre-challenge Monte Carlo production was done in several steps: physics generation, detector simulation, digitization, conversion to RAW format and the samples were run through the High Level Trigger (HLT). The data was then merged into three "Soups": Chowder (ALPGEN), Stew (Filtered Pythia) and Gumbo (Pythia). The challenge officially started when the first Chowder events were reconstructed on the Tier-0 on October 3rd. The data operations teams were very busy during the the challenge period. The MC production teams continued with signal production and processing while the Tier-0 and Tier-1 teams worked on splitting the Soups into Primary Data Sets (PDS), reconstruction and skimming. The storage sys...



    Introduction Just two months after the “LHC First Physics” event of 30th March, the analysis of the O(200) million 7 TeV collision events in CMS accumulated during the first 60 days is well under way. The consistency of the CMS computing model has been confirmed during these first weeks of data taking. This model is based on a hierarchy of use-cases deployed between the different tiers and, in particular, the distribution of RECO data to T1s, who then serve data on request to T2s, along a topology known as “fat tree”. Indeed, during this period this model was further extended by almost full “mesh” commissioning, meaning that RECO data were shipped to T2s whenever possible, enabling additional physics analyses compared with the “fat tree” model. Computing activities at the CMS Analysis Facility (CAF) have been marked by a good time response for a load almost evenly shared between ALCA (Alignment and Calibration tasks - highest p...


    I. Fisk


    Introduction The Computing Team successfully completed the storage, initial processing, and distribution for analysis of proton-proton data in 2011. There are still a variety of activities ongoing to support winter conference activities and preparations for 2012. Heavy ions The heavy-ion run for 2011 started in early November and has already demonstrated good machine performance and success of some of the more advanced workflows planned for 2011. Data collection will continue until early December. Facilities and Infrastructure Operations Operational and deployment support for WMAgent and WorkQueue+Request Manager components, routinely used in production by Data Operations, are provided. The GlideInWMS and components installation are now deployed at CERN, which is added to the GlideInWMS factory placed in the US. There has been new operational collaboration between the CERN team and the UCSD GlideIn factory operators, covering each others time zones by monitoring/debugging pilot jobs sent from the facto...

  14. Left coronary to right ventricle fistula in a child: management strategy based on cardiac-gated 64-slice CT

    Marini, Davide; Agnoletti, Gabriella; Bonnet, Damien [University Rene Descartes-Paris V, Department of Paediatric Cardiology, Hopital Necker-Enfants Malades, AP-HP, Paris (France); Brunelle, Francis; Ou, Phalla [University Rene Descartes-Paris V, Department of Paediatric Radiology, Hopital Necker-Enfants Malades, AP-HP, Paris (France)


    Congenital coronary fistulae are a diagnostic challenge. A prerequisite for best management is accurate anatomical evaluation, traditionally provided by invasive catheter angiography. Multislice CT (MSCT) is an emerging noninvasive technique for coronary artery evaluation. We present a 3-year-old boy and highlight the clinical usefulness of new-generation MSCT to study coronary artery fistulae in children. Multiplanar and 3-D reconstruction offer invaluable information to plan the best therapeutic strategy in this setting. We provide evidence for the expanding clinical role of MSCT for coronary artery imaging in children. (orig.)


    M. Kasemann

    CMS relies on a well functioning, distributed computing infrastructure. The Site Availability Monitoring (SAM) and the Job Robot submission have been very instrumental for site commissioning in order to increase availability of more sites such that they are available to participate in CSA07 and are ready to be used for analysis. The commissioning process has been further developed, including "lessons learned" documentation via the CMS twiki. Recently the visualization, presentation and summarizing of SAM tests for sites has been redesigned, it is now developed by the central ARDA project of WLCG. Work to test the new gLite Workload Management System was performed; a 4 times increase in throughput with respect to LCG Resource Broker is observed. CMS has designed and launched a new-generation traffic load generator called "LoadTest" to commission and to keep exercised all data transfer routes in the CMS PhE-DEx topology. Since mid-February, a transfer volume of about 12 P...

  16. High-performance computing and networking as tools for accurate emission computed tomography reconstruction

    Passeri, A. [Dipartimento di Fisiopatologia Clinica - Sezione di Medicina Nucleare, Universita` di Firenze (Italy); Formiconi, A.R. [Dipartimento di Fisiopatologia Clinica - Sezione di Medicina Nucleare, Universita` di Firenze (Italy); De Cristofaro, M.T.E.R. [Dipartimento di Fisiopatologia Clinica - Sezione di Medicina Nucleare, Universita` di Firenze (Italy); Pupi, A. [Dipartimento di Fisiopatologia Clinica - Sezione di Medicina Nucleare, Universita` di Firenze (Italy); Meldolesi, U. [Dipartimento di Fisiopatologia Clinica - Sezione di Medicina Nucleare, Universita` di Firenze (Italy)


    It is well known that the quantitative potential of emission computed tomography (ECT) relies on the ability to compensate for resolution, attenuation and scatter effects. Reconstruction algorithms which are able to take these effects into account are highly demanding in terms of computing resources. The reported work aimed to investigate the use of a parallel high-performance computing platform for ECT reconstruction taking into account an accurate model of the acquisition of single-photon emission tomographic (SPET) data. An iterative algorithm with an accurate model of the variable system response was ported on the MIMD (Multiple Instruction Multiple Data) parallel architecture of a 64-node Cray T3D massively parallel computer. The system was organized to make it easily accessible even from low-cost PC-based workstations through standard TCP/IP networking. A complete brain study of 30 (64 x 64) slices could be reconstructed from a set of 90 (64 x 64) projections with ten iterations of the conjugate gradients algorithm in 9 s, corresponding to an actual speed-up factor of 135. This work demonstrated the possibility of exploiting remote high-performance computing and networking resources from hospital sites by means of low-cost workstations using standard communication protocols without particular problems for routine use. The achievable speed-up factors allow the assessment of the clinical benefit of advanced reconstruction techniques which require a heavy computational burden for the compensation effects such as variable spatial resolution, scatter and attenuation. The possibility of using the same software on the same hardware platform with data acquired in different laboratories with various kinds of SPET instrumentation is appealing for software quality control and for the evaluation of the clinical impact of the reconstruction methods. (orig.). With 4 figs., 1 tab.

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

    Belinato, W., E-mail: [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: [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)


    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. Deconvolution Methods for Multi-Detectors


    this nonuniqueness , consider the one- I dimensional example of the Introduction. Let p and p 2 be compact supported and strongly coprime, and let v 1...i, E connected and aE Lipschitz . Then E (or f[) has the Pompelu property if and only if there is no positive eigenvalue for the overdetermined

  19. Role of multi-detector computed tomography (MDCT in management of post percutaneous nephrolithotomy (PCNL bleeding [v1; ref status: indexed,

    Arvind P Ganpule


    Full Text Available Objective: To evaluate the role of multidetector computerized tomography (MDCT angiography in post percutaneous nephrolithotomy (PCNL bleed and compare findings with conventional angiography (CA. Material and methods: We conducted a retrospective analysis of patients who had post PCNL bleeding and subsequently underwent a MDCT angiography followed by CA. We reviewed eight patients, who presented between January 2009 and January 2013. We performed a MDCT angiography on a 16 slice GE bright speed CT scanner. All angiographies were done by using the Digital Subtraction Angiography Suite. The angioembolisation, if required, was conducted by an interventional nephrologist, specializing in therapeutic embolisation. Results: The mean age of the patients was 42±17 years. Mean time of post PCNL bleed presentation was 10.06±7.9 days. Five patients presented with aneurysm and three presented with an AV fistula with pseudoaneurysm. The right renal unit was involved in six cases and the left in two cases. The lower polar segmental artery was involved in six cases and the upper polar artery in two cases. The CA and MDCT findings matched in all cases and the MDCT helped the clinician to assess and embolise the appropriate arterial tree. Conclusion: MDCT is rapid, reproducible and noninvasive. MDCT angiography performed in the setting of post PCNL bleeding provides an accurate assessment of the site and nature of bleeding. The MDCT angiography matched the CA findings in all patients in the present study.

  20. 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

    奚彬; 盛伟华; 唐建伟; 黄松; 宋黎涛


    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

  1. Possibilities of differentiation of solitary focal liver lesions by computed tomography perfusion

    Irmina Sefić Pašić


    Full Text Available Aim To evaluate possibilities of computed tomography (CT perfusion in differentiation of solitary focal liver lesions based on their characteristic vascularization through perfusion parameters analysis. Methods Prospective study was conducted on 50 patients in the period 2009-2012. Patients were divided in two groups: benign and malignant lesions. The following CT perfusion parameters were analyzed: blood flow (BF, blood volume (BV, mean transit time (MTT, capillary permeability surface area product (PS, hepatic arterial fraction (HAF, and impulse residual function (IRF. During the study another perfusion parameter was analyzed: hepatic perfusion index (HPI. All patients were examined on Multidetector 64-slice CT machine (GE with application of perfusion protocol for liver with i.v. administration of contrast agent. Results In both groups an increase of vascularization and arterial blood flow was noticed, but there was no significant statistical difference between any of 6 analyzed parameters. Hepatic perfusion index values were increased in all lesions in comparison with normal liver parenchyma. Conclusion Computed tomography perfusion in our study did not allow differentiation of benign and malignant liver lesions based on analysis of functional perfusion parameters. Hepatic perfusion index should be investigated in further studies as a parameter for detection of possible presence of micro-metastases in visually homogeneous liver in cases with no lesions found during standard CT protocol

  2. Computed tomography imaging of early coronary artery lesions in stable individuals with multiple cardiovascular risk factors

    Xi Yang


    Full Text Available OBJECTIVES: To investigate the prevalence, extent, severity, and features of coronary artery lesions in stable patients with multiple cardiovascular risk factors. METHODS: Seventy-seven patients with more than 3 cardiovascular risk factors were suspected of having coronary artery disease. Patients with high-risk factors and 39 controls with no risk factors were enrolled in the study. The related risk factors included hypertension, impaired glucose tolerance, dyslipidemia, smoking history, and overweight. The characteristics of coronary lesions were identified and evaluated by 64-slice coronary computed tomography angiography. RESULTS: The incidence of coronary atherosclerosis was higher in the high-risk group than in the no-risk group. The involved branches of the coronary artery, the diffusivity of the lesion, the degree of stenosis, and the nature of the plaques were significantly more severe in the high-risk group compared with the no-risk group (all p < 0.05. CONCLUSION: Among stable individuals with high-risk factors, early coronary artery lesions are common and severe. Computed tomography has promising value for the early screening of coronary lesions.

  3. Diagnostic value of appendicolith in appendicitis with multi-detector CT%阑尾石多排螺旋CT征象诊断阑尾炎的价值

    戚乐; 向军益; 戴平丰; 丁建平


    Objective To investigate the diagnostic value of appendicolith in appendicitis with multi-detector CT. Methods MDCT findings of 87 cases of appendicitis and 55 cases of non-appendicitis confirmed by surgery and clinical follow-up were retrospectively analysed. The relationship between appendicolith and appendicitis was statistically analysed. Results The appendicolith sign in MDCT was positive in 43 cases(33 cases of appendicitis and 10 cases of non-appendicitis). The appendicolith sign was not of significant difference on CT images in differential diagnosis for appendicitis and non-appendicitis, including pathologically classified (P>0. 05). The accuracy was 54. 9% , the sensitivity was 37. 9% , and the specificity was 81. 8% in diagnosing appendicititis with appendicolith sign. Obstructive appendicolith sign in 12 cases (short diameter>5 mm, located in the appendix proximal) was more seen in appendicitis group,but could identify pathologically classified(P>0. 05). The extraluminal appendicolith sign in 5 cases was seen only in gangrenous appendicitis (P<0. 05). Conclusion Obstructive appendicolith sign is helpful in diagnosis of appendicitis, and extraluminal appendicolith sign has high specificity in diagnosis of gangrenous appendicitis.%目的 探讨阑尾石MDCT征象诊断阑尾炎的价值.方法 回顾分析经手术和临床随访证实的87例阑尾炎和55例非阑尾炎患者的MDCT影像表现.统计分析阑尾石征象与阑尾炎的关系.结果 阑尾石征象阳性43例(阑尾炎患者33例,非阑尾炎患者10例),诊断阑尾炎的准确性、敏感性和特异性分别为54.9%、37.9%和81.8%,在阑尾炎组和非阑尾炎组中出现的概率无显著差异性,亦不能鉴别阑尾炎的病理分型(P>0.05).12例梗阻性阑尾石征象(短径≥5 mm,位于阑尾近端)多见于阑尾炎组,但不能鉴别阑尾炎病理分型(P>0.05).5例腔外阑尾石征象仅见于坏疽性阑尾炎(P<0.05).结论 梗阻性阑尾石征象有助于

  4. 自发性腹腔干夹层的 MSCT 血管成像表现%Imaging manifestations of spontaneous celiac artery trunk dissection with multi-detector CT angiography

    宁辉; 张龙江


    Objective:To summarize the multi-detector CT angiography (MDCTA)manifestations of spontaneous ce-liac artery trunk dissection.Methods:The clinical and MDCTA manifestations of 14 patients with spontaneous celiac artery trunk dissection were retrospectively analyzed.Results:Of the 14 patients,10 patients (71.4%,10/14)had spontaneous ce-liac artery trunk dissection,4 patients (28.6%,4/14)had both celiac artery trunk and superior mesenteric artery dissec-tion.Intimal plaque,orifice of dissection,true and false lumen were displayed in all involved 14 celiac artery trunk and 4 su-perior mesenteric artery dissections.Three dissected arteries were associated with thrombosis,2 dissected arteries with mu-ral calcification,2 dissected arteries with adjacent hematoma,and 1 with splenic infarct.Of the 14 celiac artery trunk dissec-tion,6 associated with aneurymal protrusion,and all 4 superior mesenteric artery dissection had aneurysmal protrusion asso-ciated.Two patients had celiac artery Digital Subtraction Angiography performed,the manifestations were similar to that of MSCT angiography.Intra-stent thrombosis was found in one patient underwent stent implantation.Conclusion:MDCT angi-ography can detect the pathology of celiac artery trunk dissection sensitively,which might used as the first choice modality for the diagnosis and follow up of this disease entity.%目的:总结自发性腹腔干夹层的 MSCT 血管成像表现。方法:回顾性分析14例自发性腹腔干夹层患者的临床及 MSCT 血管成像表现。结果:14例患者中自发性腹腔干夹层10例(71.4%,10/14),腹腔干和肠系膜上动脉夹层4例(28.6%,4/14)。14条腹腔干血管和4条肠系膜上动脉夹层均显示了内膜片、破口及真假腔,3条血管夹层合并血栓,2条夹层血管合并钙化,2例患者合并周围血肿,1例合并脾梗死。14条腹腔干夹层中6条血管夹层伴有动脉瘤样突起,4条肠系膜上动脉夹层

  5. Value of multi-detector spiral CT angiography in the assessment of coronary artery elasticity%多层螺旋CT血管成像在冠状动脉弹性研究中的价值

    许开元; 肖丹丹; 何祥发; 贾艳莲; 高芳琴; 张雪林


    Objective To study the efficacy of multi-detector spiral CT angiography (CTA) for evaluating coronary artery elasticity. Methods CTA was performed on 133 patients from August 2010 to April 2013..Diameter changes of 412 segment of coronary arteries in the systolic and diastolic phases were measured by CTA and digital subtraction angiography (DSA)..Coronary artery elastic parameters and elasticity index (ERI) were analyzed and correlated with DSA results. Results The ERI was positively correlated with remodeling on DSA (P0) in 46 coronary artery segments,.no significant remodeling (ERI=0) in 32 segments,.and negative remodeling (ERI<0) in 71 segments. Conclusion Multi-slice CTA can reflect the elasticity of coronary vessel walls. Compared with the results of DSA , coronary artery elasticity index correlates with the remodeling of coronary artery plaques and allows assessment of plaque instability.%目的:评价多层螺旋CT血管成像在冠状动脉弹性重塑中的价值。方法选取2010年8月~2013年4月本院行冠状动脉 CT 血管成像检查及冠脉 DSA 检查患者资料共133例,通过测量冠状动脉412节段在收缩期、舒张期的动脉管径变化,并与DSA对照,分析冠状动脉斑块处血管弹性,计算冠状动脉弹性重塑指数,并分析冠状动脉弹性重塑指数与DSA结果的相关性。结果冠状动脉弹性重塑指数(ERI)与DSA结果呈正相关,(P<0.05, r=0.402)。斑块处冠状动脉弹性正性重塑(ERI>0)46节段,无明显重塑者(ERI=0)32节段,负性重塑者(ERI<0)71节段。结论多层螺旋 CT 血管成像可较好反映正常冠状动脉血管壁弹性。与冠状动脉DSA结果相比,斑块处冠状动脉弹性重塑指数可反映斑块处冠状动脉弹性重塑情况,评价斑块稳定性。

  6. Computed Tomography evaluation of maxillofacial injuries

    V Natraj Prasad


    Full Text Available Background & Objectives: The maxillofacial region, a complex anatomical structure, can be evaluated by conventional (plain films, Tomography, Multidetector Computed Tomography, Three-Dimensional Computed Tomography, Orthopantomogram and Magnetic Resonance Imaging. The study was conducted with objective of describing various forms of maxillofacial injuries, imaging features of different types of maxillofacial fractures and the advantage of using Three- Dimensional Computed Tomography reconstructed image. Materials & Methods: A hospital based cross-sectional study was conducted among 50 patients during April 2014 to September 2016 using Toshiba Aquilion Prime 160 slice Multi Detector Computed Tomography scanner.Results: The maxillofacial fractures were significantly higher in male population (88% than female population (12 %. Road traffic accidents were the most common cause of injury others being physical assault and fall from height. It was most common in 31-40 years (26% and 21-30 (24% years age group. Maxillary sinus was the commonest fracture (36% followed by nasal bone and zygomatic bone (30%, mandible and orbital bones (28%. Soft tissue swelling was the commonest associated finding. Three dimensional images (3 D compared to the axial scans missed some fractures. However, the extension of the complex fracture lines and degree of displacement were more accurately assessed. Complex fractures found were Le fort (6% and naso-orbito-ethmoid (4% fractures.Conclusion: The proper evaluation of complex anatomy of the facial bones requires Multidetector Computed Tomography which offers excellent spatial resolution enabling multiplanar reformations and three dimensional reconstructions for enhanced diagnostic accuracy and surgical planning.

  7. Coronary computer tomographic angiography for preoperative risk stratification in patients undergoing liver transplantation

    Jodocy, Daniel, E-mail: [Department of Internal Medicine III (Cardiology), Medical University of Innsbruck, Anichstraße 35, A-6020 Innsbruck (Austria); Abbrederis, Susanne, E-mail: [Department of Internal Medicine II (Gastroenterology and Hepatology), Medical University of Innsbruck, Anichstraße 35, A-6020 Innsbruck (Austria); Graziadei, Ivo W., E-mail: [Department of Internal Medicine II (Gastroenterology and Hepatology), Medical University of Innsbruck, Anichstraße 35, A-6020 Innsbruck (Austria); Vogel, Wolfgang, E-mail: [Department of Internal Medicine II (Gastroenterology and Hepatology), Medical University of Innsbruck, Anichstraße 35, A-6020 Innsbruck (Austria); Pachinger, Otmar, E-mail: [Department of Internal Medicine III (Cardiology), Medical University of Innsbruck, Anichstraße 35, A-6020 Innsbruck (Austria); Feuchtner, Gudrun M., E-mail: [Department of Radiology, Medical University of Innsbruck, Anichstraße 35, A-6020 Innsbruck (Austria); Jaschke, Werner, E-mail: [Department of Radiology, Medical University of Innsbruck, Anichstraße 35, A-6020 Innsbruck (Austria); Friedrich, Guy, E-mail: [Department of Internal Medicine III (Cardiology), Medical University of Innsbruck, Anichstraße 35, A-6020 Innsbruck (Austria)


    The assessment of the cardiovascular risk profile in patients with end-stage liver disease is essential prior to liver transplantation (LT) as cardiovascular diseases are major causes of morbidity and mortality in the posttransplant course. The aim of this study was to evaluate the accuracy of a 64-slice coronary computed tomographic angiography (CTA) and coronary calcium scoring (CCS) to predict the postoperative cardiovascular risk of patients assessed for LT. In this single center, observational study we included 54 consecutive patients who were assessed for LT and consequently transplanted. Twenty-four patients (44%) presented with a high CCS above 300 and/or a significant stenosis (>50% percent narrowing due to stenotic plaques) and were further referred to coronary angiography. Three of these patients had a more than 70% LAD stenosis with subsequent angioplasty (n = 1) or conservative therapy (n = 2). The other patients showed only diffuse CAD without significant stenosis. The remaining 30 patients with normal CTA findings were listed for LT without further tests. None of the 54 patients developed cardiovascular events peri- and postoperatively. This study indicated that CTA combined with CCS is a useful non-invasive imaging technique for pre-LT assessment of coronary artery disease and safe tool in the risk assessment of peri- and postoperative cardiovascular events in patients undergoing LT.

  8. Prevalence of extracardiac findings in the evaluation of ischemic heart disease by multidetector computed tomography

    Jeong-Hwan Cho; Jong-Seon Park; Dong-Gu Shin; Young-Jo Kim; Sang-Hee Lee; Yoon-Jung Choi; Ihn-Ho Cho


    Objective Multidector computed tomography (MDCT) is now commonly used for the evaluation of coronary artery disease. Because MDCT images include many non-cardiac organs and the patient population evaluated is highly susceptible to extracardiac diseases, this study was designed to evaluate the prevalence of extracardiac findings in the MDCT evaluation of ischemic heart disease. Methods From March 2007 to March 2008, a total of six-hundred twenty patients, who underwent 64-slice MDCT evaluations for chest pain, or dyspnea, were enrolled in this study. Cardiac and non-cardiac findings were comprehensively evaluated by a radiologist. Results Enrolled patients included 306 men (49.4%), with a mean age of 66 years. Significant coronary artery stenosis was found in 41.6%of the patients. A total of 158 extracardiac findings were observed in 110 (17.7%) patients. Commonly involved extracardiac organs were lung (36.7%), hepatobiliary system (21.5%), thyroid (19.6%), kidney (10.8%), spine (9.7%) and breast (0.6%). Of those 110 patients, 50 (45.5%) patients underwent further diagnostic investigations. Malignant disease was detected in three (2.7%) patients (lung cancer, pancreatic cancer, and thyroid cancer). Conclusions Extracardiac findings are frequently present and should be a concern in the MDCT evaluation of chest pain syndrome.

  9. Role of multidetector computed tomography (MDCT in patients with ovarian masses

    Mubarak F, Alam MS


    Full Text Available Fatima Mubarak, Muhammad Shahbaz Alam, Waseem Akhtar, Saima Hafeez, Noureen NizamuddinRadiology Department, Aga Khan University Hospital, Karachi, PakistanObjective: To evaluate the diagnostic accuracy of multidetector 64-slice computed tomography (MDCT in the diagnosis and differentiation of benign and malignant ovarian masses using histopathology and surgical findings as the gold standard.Material and methods: This study was conducted in Aga Khan University Hospital, Karachi, Pakistan. Data was reviewed retrospectively from 1 November 2008 to 12 December 2009. One hundred patients found to have ovarian masses on CT scan were included in the study. CT scan was performed in all these patients after administration of oral and IV contrast. Ovarian masses were classified as benign and malignant on scan findings. Imaging findings were compared with histopathologic results and surgical findings. Sensitivity, specificity, positive predictive value (PPV, negative predictive value (NPV, and diagnostic accuracy of MDCT were calculated.Results: MDCT was found to have 97% sensitivity, 91% specificity, and an accuracy of 96% in the differentiation of benign and malignant ovarian masses, while PPV and NPV were 97% and 91%, respectively.Conclusion: MDCT imaging offers a safe, accurate and noninvasive modality to differentiate between benign and malignant ovarian masses.Keywords: ovarian masses, surgery, MDCT

  10. Methods of selection in heavy ion collisions at Fermi energies and de-excitation modes with the INDRA multi-detector; Methodes de tri dans les collisions d'ions lourds aux energies de Fermi et modes de desexcitation avec le multidetecteur INDRA

    Lautesse, Ph


    The progress made in particle detection, particularly the design of multi-detectors, like INDRA, that cover a solid angle of almost 4{pi}, have given a new impetus to heavy ion collisions. These detectors are demanding for an efficient way of selecting events that have a common history or similar features, for instance the events representing the de-excitation of a unique emitter. The problem is to find the adequate variable on which the discrimination can be based. Different methods are proposed in this work, the common point is that they require efficient models to reproduce and analyse experimental data in order to apprehend the equation of state of nuclear matter. Most of these models are based on the numerically solving of the nuclear Boltzmann equation. The application to the Ni + Ni reaction with an energy ranging from a few A.MeV to more than 50 A.MeV illustrates this work. (A.C.)

  11. 急性胰腺炎64层螺旋CT灌注成像研究%Acute Pancreatitis: 64-slice Spiral CT Perfusion Imaging

    姜海峰; 郭顺林; 周怀琪; 王刚; 张安; 徐风


    目的 探讨64层螺旋CT灌注成像在急性胰腺炎诊断中的作用.方法 分别对胰腺正常者30例和急性胰腺炎患者28例行Siemens 64层螺旋CT胰腺灌注检查,采用Siemens Body Perfusion软件测量所有病例的胰头部、胰体尾部的CT灌注参数:血流量(blood flow,BF)、血流容积(blood volume,BV)、灌注起始时间(time to start,TTS)、达峰时间(time to peak,TTP)、渗透性(permeability,P)、patlak血流容积(patlak blood volume,pBV)的平均值, 并进行统计学分析.结果 Siemens灌注软件计算所得时间-密度曲线(density-time curve,TDC)符合数据分析要求.统计数据结果显示急性胰腺炎组胰头部和体尾部的BF、BV、 pBV明显低于正常胰腺组,而其渗透性高于正常胰腺组, 差异均有显著的统计学意义(P0.05);急性胰腺炎组、正常胰腺组各自的胰头部与胰体尾部之间各灌注参数 无统计学意义(P>0.05).结论 64层螺旋CT灌注成像能够反映急性胰腺炎的血流灌注改变,对其临床的早期诊断有重要的指导意义.

  12. Comparison of findings of spontaneous splenorenal shunt in color Doppler sonography with multislice CT scan (64 slices) in liver transplant candidates

    Bagheri, Mohammadhadi, E-mail: [Department of Radiology, Shiraz University of Medical Sciences, Namazi Hospital, Shiraz (Iran, Islamic Republic of); Hajati, Azadeh, E-mail: [Department of Radiology, Shiraz University of Medical Sciences, Namazi Hospital, Shiraz (Iran, Islamic Republic of); Hosseini, Mohammadkazem, E-mail: [Department of Radiology, Shiraz University of Medical Sciences, Namazi Hospital, Shiraz (Iran, Islamic Republic of); Ostad, Seyed Pouria, E-mail: [Department of Radiology, Shiraz University of Medical Sciences, Namazi Hospital, Shiraz (Iran, Islamic Republic of)


    Background: Liver transplantation is the only definite treatment for end stage liver disease and it has high costs for the medical system so decreasing its complication and increasing its effectiveness is crucial. One of the factors that affect liver transplantation is the presence of spontaneous splenorenal shunt. Its diagnosis is mainly overlooked in pre-liver transplant patients. Main modality for its diagnosis is multislice CT scan however this is more expensive than sonography. Also, it exposes the patients to ionizing radiation. Considering the advantages of color Doppler ultrasound, studies to determine the sensitivity and specificity for detection of spontaneous splenorenal shunt is essential. Materials and methods: In our study 70 cirrhotic patients who were referred by liver transplant surgeons for evaluation of abdomen by CT and sonograhy were assessed for presence of spontaneous splenorenal shunt, left adrenal varix and left renal vein diameter and velocity and sensitivity and specificity of both modalities were checked. Patients in whom left renal vein could not evaluated by sonography and patients with splenectomy and nutcracker syndrome were excluded. Results: In the point of 10 mm diameter of left renal vein in CT scan there was 78.6% sensitivity and 67.9% specificity for the presence of spontaneous splenorenal shunt. Left adrenal varix in CT had sensitivity of 71.4%, specificity of 100%, and positive predictive value of 100% and negative predictive value of 70% and varix below spleen in CT had sensitivity of 54.8%, specificity of 96.4%, and positive predictive value of 95.8% and negative predictive value of 58.7% for the presence of spontaneous splenorenal shunt. In the point of 8 mm diameter of left renal vein in sonography there was 66.7% sensitivity and 85.7% specificity for the presence of spontaneous splenorenal shunt. For the velocity of more than 35 cm/s of left renal vein in sonography there was 61.9% sensitivity and 82.1% specificity for the presence of spontaneous splenorenal shunt. Left adrenal varix in sonography had sensitivity of 45.2%, specificity of 96.4%, positive predictive value of 95% and negative predictive value of 54% for the presence of spontaneous splenorenal shunt. Conclusion: There was moderate agreement between CT scan and sonography for detection of spontaneous splenorenal shunt. CT scan is choice for detection of SSRS but sonography is somehow useful. It means that if sonograhy is positive it is sufficient, if negative, then CT should be performed. This is due to low sensitivity of sonography.

  13. 64-slices spiral CT for detection of patent foramen ovale%64层螺旋CT对卵圆孔未闭的检测

    毛定飚; 滑炎卿; 吴昊; 葛虓俊; 唐平; 郑向鹏; 张国桢


    @@ 近年来国外文献报道卵圆孔未闭(patent foramen ovale,PFO)的存在与反常栓塞、缺血性脑卒中、偏头痛、潜水减压病等的发生密切相关,与冠状动脉旁路移植术及各种心、肺手术后不明原因的卒中或猝死也有关系[1-2].本研究通过对186例患者进行心电门控64层CT心脏成像探讨CT检测PFO的可行性.

  14. Assessment of Blood Flow in Hepatocellular Carcinoma: Correlations of Computed Tomography Perfusion Imaging and Circulating Angiogenic Factors

    Chen-Pin Chou


    Full Text Available Hepatocellular carcinoma (HCC is a highly vascular tumor through the process of angiogenesis. To evaluate more non-invasive techniques for assessment of blood flow (BF in HCC, this study examined the relationships between BF of HCC measured by computer tomography (CT perfusion imaging and four circulating angiogenic factors in HCC patients. Interleukin 6 (IL-6, interleukin 8 (IL-8, vascular endothelial growth factor (VEGF, and platelet derived growth factor (PDGF in plasma were measured using Bio-Plex multiplex immunoassay in 21 HCC patients and eight healthy controls. Circulating IL-6, IL-8 and VEGF showed higher concentrations in HCC patients than in controls (p < 0.05, and predicted HCC occurrence better than chance (p < 0.01. Twenty-one patients with HCC received 21-phase liver imaging using a 64-slice CT. Total BF, arterial BF, portal BF, arterial fraction (arterial BF/total BF of the HCC and surrounding liver parenchyma, and HCC-parenchyma ratio were measured using a dual-vessel model. After analyzing the correlations between BF in HCC and four circulating angiogenic factors, we found that the HCC-parenchyma ratio of arterial BF showed a significantly positive correlation with the level of circulating IL-8 (p < 0.05. This circulating biomarker, IL-8, provides a non-invasive tool for assessment of BF in HCC.

  15. Improvement of distension and mural visualization of bowel loops using neutral oral contrasts in abdominal computed tomography

    Jahanbakhsh; Hashemi; Yasmin; Davoudi; Mina; Taghavi; Masoud; Pezeshki; Rad; Amien; Mahajeri; Moghadam


    AIM: To assess and compare the image quality of 4% sorbitol and diluted iodine 2%(positive oral contrast agent) in abdomino-pelvic multi-detector computed tomography.METHODS: Two-hundred patients, referred to the Radiology Department of a central educational hospital for multi-detector row abdominal-pelvic computed tomography, were randomly divided into two groups: the first group received 1500 m L of 4% sorbitol solution as a neutral contrast agent, while in the second group 1500 m L of meglumin solution as a positive contrast agent was administered in a one-way randomized prospective study. The results were independently reviewed by two radiologists. Luminal distension and mural thickness and mucosal enhancement were compared between the two groups. Statistical analysis of the results was performed by Statistical Package for the Social Sciences software version 16 and the Mann-Whitney test at a confidence level of 95%. RESULTS: Use of neutral oral contrast agent significantly improved visualization of the small bowel wall thickness and mural appearance in comparison with administration of positive contrast agent(P < 0.01). In patients who received sorbitol, the small bowel showed better distention compared with those who received iodine solution as a positive contrast agent(P < 0.05). CONCLUSION: The results of the study demonstrated that oral administration of sorbitol solution allows better luminal distention and visualization of mural features than iodine solution as a positive contrast agent.

  16. Experimental study about the effect of different scan parameters and post-processing methods of multi-detector CT on metallic artifacts%多排螺旋 CT 不同扫描参数及图像后处理方式对金属伪影的影响

    储斌; 邹月芬; 王传兵


    目的:探讨多排螺旋 CT(MDCT)扫描参数及图像后处理方式对金属植入物伪影的影响,以期获得最佳方案减少金属伪影。方法制作钛合金钢板水模,将其置入 MDCT 下通过调节不同参数进行扫描(包括管电压、管电流、螺距、焦点),然后测定所得图像伪影面积大小并评价其相关性;对常规扫描参数下获得的15例椎体内固定术后患者图像进行后处理,分别使用常规方式和优化方式重建,包括多平面重建(MPR)、调节窗宽窗位及容积再现技术(VRT),然后评价图像质量。结果不同管电压、螺距、焦点下,伪影面积差异有统计学意义,随着管电压升高,伪影面积逐渐减小;随着螺距减小,伪影面积逐渐减小;使用小焦点扫描较大焦点伪影面积小;不同管电流下,伪影面积差异无统计学意义。图像后处理时骨窗重建选择软组织算法(Kernel B40f)、观察时选择窗位600 HU、窗宽2000 HU 及 VRT 三维重建可减少金属伪影。结论选择适当的 MDCT 扫描参数及图像后处理方式可以减少金属伪影,提高图像质量,有助于影像诊断。%Objective To explore the effect of multi-detector computed tomography (MDCT)scan parameters and imaging post-processing methods on metallic artifacts,so as to achieve the perfection in reduction of artifacts caused by metallic implants.Methods Water phantom with titanium alloy steel plate was scanned under MDCT with alternating scan parameters including tube voltage, tube current,pitch and focal spot.The areas of image artifacts were measured and correlated with the scan parameters.Another 1 5 postoperative patients with vertebral implantation scaned with the conventional scan parameters were also included in the study.Ima-ging post-processing including multi-planar reconstruction (MPR),window width and level adjustment,and volume rendering tech-nique (VRT)was performed by using optimized and

  17. Impact of sirolimus-eluting stent fractures without early cardiac events on long-term clinical outcomes: A multislice computed tomography study

    Ito, Tsuyoshi [Toyohashi Heart Center, Oyama-cho, Toyohashi (Japan); Nagoya City University Graduate School of Medical Sciences, Department of Cardio-Renal Medicine and Hypertension, Nagoya (Japan); Kimura, Masashi; Ehara, Mariko; Terashima, Mitsuyasu; Nasu, Kenya; Kinoshita, Yoshihisa; Habara, Maoto; Tsuchikane, Etsuo; Suzuki, Takahiko [Toyohashi Heart Center, Oyama-cho, Toyohashi (Japan)


    This study sought to evaluate the impact of sirolimus-eluting stent (SES) fractures on long-term clinical outcomes using multislice computed tomography (MSCT). In this study, 528 patients undergoing 6- to 18-month follow-up 64-slice MSCT after SES implantation without early clinical events were followed clinically (the median follow-up interval was 4.6 years). A CT-detected stent fracture was defined as a complete gap with Hounsfield units (HU) <300 at the site of separation. The major adverse cardiac events (MACEs), including cardiac death, stent thrombosis, and target lesion revascularisation, were compared according to the presence of stent fracture. Stent fractures were observed in 39 patients (7.4 %). MACEs were more common in patients with CT-detected stent fractures than in those without (46 % vs. 7 %, p < 0.01). Univariate Cox regression analysis indicated a significant relationship between MACE and stent fracture [hazard ratio (HR) 7.65; p < 0.01], age (HR 1.03; p = 0.04), stent length (HR 1.03; p < 0.01), diabetes mellitus (HR 1.77; p = 0.04), and chronic total occlusion (HR 2.54; p = 0.01). In the multivariate model, stent fracture (HR 5.36; p < 0.01) and age (HR 1.03; p = 0.04) remained significant predictors of MACE. An SES fracture detected by MSCT without early clinical events was associated with long-term clinical adverse events. (orig.)

  18. Intracranial arterial anatomy: evaluation by computed tomography angiography; Anatomia arterial intracraniana: avaliacao por angiotomografia computadorizada

    Regattieri, Neysa Aparecida Tinoco, E-mail: [Universidade Tecnologica Federal do Parana (UTFPR), Curitiba, PR (Brazil); Haetinger, Rainer Guilherme; Liberti, Edson Aparecido [Universidade de Sao Paulo (ICB III/USP), SP (Brazil). Inst. de Ciencias Biomedicas; Piske, Ronie Leo [Hospital Beneficencia Portuguesa de Sao Paulo, SP (Brazil)


    By many decades, the intracranial arteries study was realized exclusively by angiography through selective arterial catheterization. Nowadays, with the technologic evaluation of computerized tomography devices with multi detectors allowing acquisitions with even more thinner slices, higher speed and better resolution, it had appeared a new modality of investigation: the computed tomography angiography, less invasive and with minor morbidity than conventional arteriography. Many studies in the literature have been analyzing the sensibility of the new method for the detection of intracranial aneurysms and comparing them with the conventional arteriography. There is a necessity to recognize the normal intracranial arterial anatomy and its variations using images obtained from multiplanar reformations, in order to give important information for surgeries strategies, such as wall calcifications, aneurismatic neck position and relationships with surrounding anatomical structures. (author)

  19. Computer-aided detection of small bowel strictures in CT enterography

    Sainani, Nisha I.; Näppi, Janne J.; Sahani, Dushyant V.; Yoshida, Hiroyuki


    The workflow of CT enterography in an emergency setting could be improved significantly by computer-aided detection (CAD) of small bowel strictures to enable even non-expert radiologists to detect sites of obstruction rapidly. We developed a CAD scheme to detect strictures automatically from abdominal multi-detector CT enterography image data by use of multi-scale template matching and a blob detector method. A pilot study was performed on 15 patients with 22 surgically confirmed strictures to study the effect of the CAD scheme on observer performance. The 77% sensitivity of an inexperienced radiologist assisted by CAD was comparable with the 81% sensitivity of an unaided expert radiologist (p=0.07). The use of CAD reduced the reading time to identify strictures significantly (pmuscles, or vessels, and they were easy to dismiss. The results indicate that CAD could provide radiologists with a rapid and accurate interpretation of strictures to improve workflow in an emergency setting.

  20. The effects of computed tomography with iterative reconstruction on solid pulmonary nodule volume quantification.

    Martin J Willemink

    Full Text Available BACKGROUND: The objectives of this study were to evaluate the influence of iterative reconstruction (IR on pulmonary nodule volumetry with chest computed tomography (CT. METHODS: Twenty patients (12 women and 8 men, mean age 61.9, range 32-87 underwent evaluation of pulmonary nodules with a 64-slice CT-scanner. Data were reconstructed using filtered back projection (FBP and IR (Philips Healthcare, iDose(4-levels 2, 4 and 6 at similar radiation dose. Volumetric nodule measurements were performed with semi-automatic software on thin slice reconstructions. Only solid pulmonary nodules were measured, no additional selection criteria were used for the nature of nodules. For intra-observer and inter-observer variability, measurements were performed once by one observer and twice by another observer. Algorithms were compared using the concordance correlation-coefficient (pc and Friedman-test, and post-hoc analysis with the Wilcoxon-signed ranks-test with Bonferroni-correction (significance-level p<0.017. RESULTS: Seventy-eight nodules were present including 56 small nodules (volume<200 mm(3, diameter<8 mm and 22 large nodules (volume≥200 mm(3, diameter≥8 mm. No significant differences in measured pulmonary nodule volumes between FBP, iDose(4-levels 2, 4 and 6 were found in both small nodules and large nodules. FBP and iDose(4-levels 2, 4 and 6 were correlated with pc-values of 0.98 or higher for both small and large nodules. Pc-values of intra-observer and inter-observer variability were 0.98 or higher. CONCLUSIONS: Measurements of solid pulmonary nodule volume measured with standard-FBP were comparable with IR, regardless of the IR-level and no significant differences between measured volumes of both small and large solid nodules were found.

  1. Late enhanced computed tomography in Hypertrophic Cardiomyopathy enables accurate left-ventricular volumetry

    Langer, Christoph; Lutz, M.; Kuehl, C.; Frey, N. [Christian-Albrechts-Universitaet Kiel, Department of Cardiology, Angiology and Critical Care Medicine, University Medical Center Schleswig-Holstein (Germany); Partner Site Hamburg/Kiel/Luebeck, DZHK (German Centre for Cardiovascular Research), Kiel (Germany); Both, M.; Sattler, B.; Jansen, O; Schaefer, P. [Christian-Albrechts-Universitaet Kiel, Department of Diagnostic Radiology, University Medical Center Schleswig-Holstein (Germany); Harders, H.; Eden, M. [Christian-Albrechts-Universitaet Kiel, Department of Cardiology, Angiology and Critical Care Medicine, University Medical Center Schleswig-Holstein (Germany)


    Late enhancement (LE) multi-slice computed tomography (leMDCT) was introduced for the visualization of (intra-) myocardial fibrosis in Hypertrophic Cardiomyopathy (HCM). LE is associated with adverse cardiac events. This analysis focuses on leMDCT derived LV muscle mass (LV-MM) which may be related to LE resulting in LE proportion for potential risk stratification in HCM. N=26 HCM-patients underwent leMDCT (64-slice-CT) and cardiovascular magnetic resonance (CMR). In leMDCT iodine contrast (Iopromid, 350 mg/mL; 150mL) was injected 7 minutes before imaging. Reconstructed short cardiac axis views served for planimetry. The study group was divided into three groups of varying LV-contrast. LeMDCT was correlated with CMR. The mean age was 64.2 ± 14 years. The groups of varying contrast differed in weight and body mass index (p < 0.05). In the group with good LV-contrast assessment of LV-MM resulted in 147.4 ± 64.8 g in leMDCT vs. 147.1 ± 65.9 in CMR (p > 0.05). In the group with sufficient contrast LV-MM appeared with 172 ± 30.8 g in leMDCT vs. 165.9 ± 37.8 in CMR (p > 0.05). Overall intra-/inter-observer variability of semiautomatic assessment of LV-MM showed an accuracy of 0.9 ± 8.6 g and 0.8 ± 9.2 g in leMDCT. All leMDCT-measures correlated well with CMR (r > 0.9). LeMDCT primarily performed for LE-visualization in HCM allows for accurate LV-volumetry including LV-MM in > 90 % of the cases. (orig.)

  2. Simple area-based measurement for multidetector computed tomography to predict left ventricular size

    Schlett, Christopher L.; Kwait, Dylan C.; Mahabadi, Amir A.; Hoffmann, Udo [Massachusetts General Hospital, and Harvard Medical School, Cardiac MR PET CT Program, Boston, MA (United States); Bamberg, Fabian [Massachusetts General Hospital, and Harvard Medical School, Cardiac MR PET CT Program, Boston, MA (United States); University Hospitals Munich, and Ludwig Maximilians University, Department of Clinical Radiology, Munich (Germany); O' Donnell, Christopher J. [Lung and Blood Institute' s Framingham Heart Study, National Heart, Framingham (United States); Fox, Caroline S. [Lung and Blood Institute' s Framingham Heart Study, National Heart, Framingham (United States); Brigham and Women' s Hospital, and Harvard Medical School, Division of Endocrinology, Metabolism, and Diabetes, Department of Medicine, Boston, MA (United States)


    Measures of left ventricular (LV) mass and dimensions are independent predictors of morbidity and mortality. We determined whether an axial area-based method by computed tomography (CT) provides an accurate estimate of LV mass and volume. A total of 45 subjects (49% female, 56.0 {+-} 12 years) with a wide range of LV geometry underwent contrast-enhanced 64-slice CT. LV mass and volume were derived from 3D data. 2D images were analysed to determine LV area, the direct transverse cardiac diameter (dTCD) and the cardiothoracic ratio (CTR). Furthermore, feasibility was confirmed in 100 Framingham Offspring Cohort subjects. 2D measures of LV area, dTCD and CTR were 47.3 {+-} 8 cm{sup 2}, 14.7 {+-} 1.5 cm and 0.54 {+-} 0.05, respectively. 3D-derived LV volume (end-diastolic) and mass were 148.9 {+-} 45 cm{sup 3} and 124.2 {+-} 34 g, respectively. Excellent inter- and intra-observer agreement were shown for 2D LV area measurements (both intraclass correlation coefficients (ICC) = 0.99, p < 0.0001) and could be confirmed on non-contrast CT. The measured 2D LV area was highly correlated to LV volume, mass and size (r = 0.68; r = 0.73; r = 0.82; all p < 0.0001, respectively). On the other hand, CTR was not correlated to LV volume, mass, size or 2D LV area (all p > 0.27). Compared with traditionally used CTR, LV size can be accurately predicted based on a simple and highly reproducible axial LV area-based measurement. (orig.)

  3. Coronary computed tomography angiography: overview of technical aspects, current concepts, and perspectives

    Chartrand-Lefebvre, C.; Cadrin-Chenevert, A. [Univ. of Montreal Medical Centre, Radiology Dept., Montreal, Quebec (Canada)]. E-mail:; Bordeleau, E. [Univ. of Montreal Medical Centre, Radiology Dept., Montreal, Quebec (Canada); Hopital Laval, St. Foy, Quebec (Canada); Ugolini, P.; Ouellet, R. [Montreal Inst. of Cardiology, Montreal, Quebec (Canada); Sablayrolles, J.-L. [Centre Cardiologique du Nord, Paris (France); Prenovault, J. [Univ. of Montreal Medical Centre, Radiology Dept., Montreal, Quebec (Canada)


    Multidetector-row electrocardiogram (ECC)-gated cardiac computed tomography (CT) will probably be a major noninvasive imaging option in the near future. Recent developments indicate that this new technology is improving rapidly. This article presents an overview of the current concepts, perspectives, and technical capabilities in coronary CT angiography (CTA). We have reviewed the recent literature on the different applications of this technology; of particular note are the many studies that have demonstrated the high negative predictive value (NPV) of coronary CTA, when performed under optimal conditions, for significant stenoses in native coronary arteries. This new technology's level of performance allows it to be used to evaluate the presence of calcified plaques, coronary bypass graft patency, and the origin and course of congenital coronary anomalies. Despite a high NPV, the robustness of the technology is limited by arrhythmias, the requirement of low heart rates, and calcium-related artifacts. Sonic improvements are needed in the imaging of coronary stents, especially the smaller stents, and in the detection and characterization of noncalcified plaques. Further studies are needed to more precisely determine the role of CTA in various symptomatic and asymptomatic patient groups. Clinical testing of 64-slice scanners has recently begun. As the technology improves, so does the spatial and temporal resolution. To date, this is being achieved through the development of systems with an increased number of detectors and shorter gantry rotation time as well as the development of systems equipped with 2 X-ray tubes and the eventual development of flat-panel technology. Thus further improvement of image quality is expected. (author)

  4. MDCT定量评价腔内血栓形成的腹主动脉瘤瘤体弹性%Quantitative Assessment of Abdominal Aortic Aneurysm Sac Distensibility with Intraluminal Thrombus Using Multi-Detector CT

    李莉丽; 查云飞; 李亮; 彭宙峰; 陆雪松


    Objective To noninvasively and quantitatively evaluate the distensibility of abdominal aortic aneurysm sac(AAAs) with intraluminal thrombus using 64 MDCT.Methods 31 patients with AAAs underwent computed tomography angiography (CTA)examination.Time resolved images were acquired with the retrospective ECG-gated technology and section data acquisition mode.Scan data were reconstructed at 20 phases between 0% and 95% of the R-R intervals with an increment of 5%.All reconstructed images were analyzed using algorithm developed Matlab 7.5 (Version R2007b,the MathWorks,Natick,MA,USA).At different phases,AAA sac diameter,max and minimal area,distensibility values were calculated in the lumen and wall.Results Aneurysm sac diameter had not any correlation with distensibility(rwall =-0.315,rlumen =-0.251,Pwall,lumen > 0.05).Mean distensibility of Dlumen and Dwall were (1.15 ± 0.47) ×10-5Pa-1 and (0.95 ± 0.48) × 10-5 pa-1,respectively.A significant difference of distensibility between AAA wall and AAA lumen was proved (P < 0.05) also by use of the Wilcoxon test.Distensibility of the AAA wall was significantly lower than that of AAA lumen.Conclusion AAA distensibility is completely independent of the aneurysm size,and the distensibility of lumen is significantly higher than that of wall.Distensibility assessment could be a valuble method for the diagnosis and treatment for abdominal aortic aneurysm.%目的 探讨64排CT定量评价腔内血栓腹主动脉瘤瘤体弹性.方法 对31例含腔内血栓腹主动脉瘤患者采用回顾性心电门控技术和分段数据采集方式行腹主动脉64排螺旋CT血管成像.将获得的原始数据在0%~ 95% R-R间期,间隔5%分别重组图像,采用MATLAB 7.5软件行半自动图像分割方法,然后分别测量各期相内瘤体直径、最大和最小面积及弹性D值等指标在管腔及管壁方面的变化.结果 腹主动脉瘤瘤体最大直径与管壁、管腔弹性值间均

  5. Assessment of three root canal preparation techniques on root canal geometry using micro-computed tomography: In vitro study

    Shaikha M Al-Ali


    Full Text Available Aim: To assess the effects of three root canal preparation techniques on canal volume and surface area using three-dimensionally reconstructed root canals in extracted human maxillary molars. Materials and Methods: Thirty extracted Human Maxillary Molars having three separate roots and similar root shape were randomly selected from a pool of extracted teeth for this study and stored in normal saline solution until used. A computed tomography scanner (Philips Brilliance CT 64-slice was used to analyze root canals in extracted maxillary molars. Specimens were scanned before and after canals were prepared using stainless steel K-Files, Ni-Ti rotary ProTaper and rotary SafeSiders instruments. Differences in dentin volume removed, the surface area, the proportion of unchanged area and canal transportation were calculated using specially developed software. Results: Instrumentation of canals increased volume and surface area. Statistical analysis found a statistically significant difference among the 3 groups in total change in volume (P = 0.001 and total change in surface area (P = 0.13. Significant differences were found when testing both groups with group III (SafeSiders. Significant differences in change of volume were noted when grouping was made with respect to canal type (in MB and DB (P < 0.05. Conclusion: The current study used computed tomography, an innovative and non destructive technique, to illustrate changes in canal geometry. Overall, there were few statistically significant differences between the three instrumentation techniques used. SafeSiders stainless steel 40/0.02 instruments exhibit a greater cutting efficiency on dentin than K-Files and ProTaper. CT is a new and valuable tool to study root canal geometry and changes after preparation in great details. Further studies with 3D-techniques are required to fully understand the biomechanical aspects of root canal preparation.

  6. Prior image constrained image reconstruction in emerging computed tomography applications

    Brunner, Stephen T.

    Advances have been made in computed tomography (CT), especially in the past five years, by incorporating prior images into the image reconstruction process. In this dissertation, we investigate prior image constrained image reconstruction in three emerging CT applications: dual-energy CT, multi-energy photon-counting CT, and cone-beam CT in image-guided radiation therapy. First, we investigate the application of Prior Image Constrained Compressed Sensing (PICCS) in dual-energy CT, which has been called "one of the hottest research areas in CT." Phantom and animal studies are conducted using a state-of-the-art 64-slice GE Discovery 750 HD CT scanner to investigate the extent to which PICCS can enable radiation dose reduction in material density and virtual monochromatic imaging. Second, we extend the application of PICCS from dual-energy CT to multi-energy photon-counting CT, which has been called "one of the 12 topics in CT to be critical in the next decade." Numerical simulations are conducted to generate multiple energy bin images for a photon-counting CT acquisition and to investigate the extent to which PICCS can enable radiation dose efficiency improvement. Third, we investigate the performance of a newly proposed prior image constrained scatter correction technique to correct scatter-induced shading artifacts in cone-beam CT, which, when used in image-guided radiation therapy procedures, can assist in patient localization, and potentially, dose verification and adaptive radiation therapy. Phantom studies are conducted using a Varian 2100 EX system with an on-board imager to investigate the extent to which the prior image constrained scatter correction technique can mitigate scatter-induced shading artifacts in cone-beam CT. Results show that these prior image constrained image reconstruction techniques can reduce radiation dose in dual-energy CT by 50% in phantom and animal studies in material density and virtual monochromatic imaging, can lead to radiation

  7. Quantitative analysis of left ventricular strain using cardiac computed tomography

    Buss, Sebastian J., E-mail: [Department of Cardiology, University of Heidelberg, 69120 Heidelberg (Germany); Schulz, Felix; Mereles, Derliz [Department of Cardiology, University of Heidelberg, 69120 Heidelberg (Germany); Hosch, Waldemar [Department of Diagnostic and Interventional Radiology, University of Heidelberg, 69120 Heidelberg (Germany); Galuschky, Christian; Schummers, Georg; Stapf, Daniel [TomTec Imaging Systems GmbH, Munich (Germany); Hofmann, Nina; Giannitsis, Evangelos; Hardt, Stefan E. [Department of Cardiology, University of Heidelberg, 69120 Heidelberg (Germany); Kauczor, Hans-Ulrich [Department of Diagnostic and Interventional Radiology, University of Heidelberg, 69120 Heidelberg (Germany); Katus, Hugo A.; Korosoglou, Grigorios [Department of Cardiology, University of Heidelberg, 69120 Heidelberg (Germany)


    Objectives: To investigate whether cardiac computed tomography (CCT) can determine left ventricular (LV) radial, circumferential and longitudinal myocardial deformation in comparison to two-dimensional echocardiography in patients with congestive heart failure. Background: Echocardiography allows for accurate assessment of strain with high temporal resolution. A reduced strain is associated with a poor prognosis in cardiomyopathies. However, strain imaging is limited in patients with poor echogenic windows, so that, in selected cases, tomographic imaging techniques may be preferable for the evaluation of myocardial deformation. Methods: Consecutive patients (n = 27) with congestive heart failure who underwent a clinically indicated ECG-gated contrast-enhanced 64-slice dual-source CCT for the evaluation of the cardiac veins prior to cardiac resynchronization therapy (CRT) were included. All patients underwent additional echocardiography. LV radial, circumferential and longitudinal strain and strain rates were analyzed in identical midventricular short axis, 4-, 2- and 3-chamber views for both modalities using the same prototype software algorithm (feature tracking). Time for analysis was assessed for both modalities. Results: Close correlations were observed for both techniques regarding global strain (r = 0.93, r = 0.87 and r = 0.84 for radial, circumferential and longitudinal strain, respectively, p < 0.001 for all). Similar trends were observed for regional radial, longitudinal and circumferential strain (r = 0.88, r = 0.84 and r = 0.94, respectively, p < 0.001 for all). The number of non-diagnostic myocardial segments was significantly higher with echocardiography than with CCT (9.6% versus 1.9%, p < 0.001). In addition, the required time for complete quantitative strain analysis was significantly shorter for CCT compared to echocardiography (877 ± 119 s per patient versus 1105 ± 258 s per patient, p < 0.001). Conclusion: Quantitative assessment of LV strain

  8. Multi-detector CT in the paediatric urinary tract

    Damasio, M.B., E-mail: [Paediatric Radiology, Giannina Gaslini Institute, Genoa (Italy); Darge, K. [Department of Radiology, Children' s Hospital of Philadelphia, Philadelphia (United States); Riccabona, M. [Department of Radiology, Division of Paediatric Radiology, University Hospital Graz (Austria)


    The use of paediatric multi-slice CT (MSCT) is rapidly increasing worldwide. As technology advances its application in paediatric care is constantly expanding with an increasing need for radiation dose control and appropriate utilization. Recommendations on how and when to use CT for assessment of the paediatric urinary tract appear to be an important issue. Therefore the European Society of Paediatric Radiology (ESPR) uroradiology task force and European Society of Urogenital Radiology (ESUR) paediatric working groups created a proposal for performing renal CT in children that has recently been published. The objective of this paper is to discuss paediatric urinary tract CT (uro-CT) in more detail and depth. The specific aim is not only to offer general recommendations on clinical indications and optimization processes of paediatric CT examination, but also to address various childhood characteristics and phenomena that facilitate understanding the different approach and use of uro-CT in children compared to adults. According to ALARA principles, paediatric uro-CT should only be considered for selected indications provided high-level comprehensive US is not conclusive and alternative non-ionizing techniques such as MR are not available or appropriate. Optimization of paediatric uro-CT protocols (considering lower age-adapted kV and mAs) is mandatory, and the number of phases and acquisition series should be kept as few as possible.

  9. Multi-Detector Analysis System for Spent Nuclear Fuel Characterization

    Reber, Edward Lawrence; Aryaeinejad, Rahmat; Cole, Jerald Donald; Drigert, Mark William; Jewell, James Keith; Egger, Ann Elizabeth; Cordes, Gail Adele


    The Spent Nuclear Fuel (SNF) Non-Destructive Analysis (NDA) program at INEEL is developing a system to characterize SNF for fissile mass, radiation source term, and fissile isotopic content. The system is based on the integration of the Fission Assay Tomography System (FATS) and the Gamma-Neutron Analysis Technique (GNAT) developed under programs supported by the DOE Office of Non-proliferation and National Security. Both FATS and GNAT were developed as separate systems to provide information on the location of special nuclear material in weapons configuration (FATS role), and to measure isotopic ratios of fissile material to determine if the material was from a weapon (GNAT role). FATS is capable of not only determining the presence and location of fissile material but also the quantity of fissile material present to within 50%. GNAT determines the ratios of the fissile and fissionable material by coincidence methods that allow the two prompt (immediately) produced fission fragments to be identified. Therefore, from the combination of FATS and GNAT, MDAS is able to measure the fissile material, radiation source term, and fissile isotopics content.

  10. Enhanced security for multi-detector Quantum Random Number Generators

    Marangon, Davide G.; Vallone, Giuseppe; Zanforlin, Ugo; Villoresi, Paolo


    Quantum random number generators (QRNG) represent an advanced solution for randomness generation, essential in every cryptographic applications. In this context, integrated arrays of single photon detectors have promising applications as QRNGs based on the spatial detection of photons. For the employment of QRNGs in Cryptography, it is necessary to have efficient methods to evaluate the so called quantum min-entropy that corresponds to the amount of the true extractable quantum randomness fro...

  11. Automatic individualized contrast medium dosage during hepatic computed tomography by using computed tomography dose index volume (CTDI{sub vol})

    Svensson, Anders; Cederlund, Kerstin; Aspelin, Peter; Brismar, Torkel B. [Intervention and Technology at Karolinska Institutet, Department of Clinical Science, Division of Medical Imaging and Technology, Stockholm (Sweden); Karolinska University Hospital in Huddinge, Department of Radiology, Stockholm (Sweden); Bjoerk, Jonas [FoU-centrum Skaane Skaanes Universitetssjukhus i Lund, Lund (Sweden); Nyman, Ulf [University of Lund, Department of Diagnostic Radiology, Lasarettet Trelleborg, Trelleborg (Sweden)


    To compare hepatic parenchymal contrast media (CM) enhancement during multi-detector row computed tomography (MDCT) and its correlation with volume pitch-corrected computed tomography dose index (CTDI{sub vol}) and body weight (BW). One hundred patients referred for standard three-phase thoraco-abdominal MDCT examination were enrolled. BW was measured in the CT suite. Forty grams of iodine was administered intravenously (iodixanol 320 mg I/ml at 5 ml/s or iomeprol 400 mg I/ml at 4 ml/s) followed by a 50-ml saline flush. CTDI{sub vol} presented by the CT equipment during the parenchymal examination was recorded. The CM enhancement of the liver was defined as the attenuation HU of the liver parenchyma during the hepatic parenchymal phase minus the attenuation in the native phase. Liver parenchymal enhancement was negatively correlated to both CTDI{sub vol} (r = -0.60) and BW (r = -0.64), but the difference in correlation between those two was not significant. CTDI{sub vol} may replace BW when adjusting CM doses to body size. This makes it potentially feasible to automatically individualize CM dosage by CT. (orig.)

  12. Computed tomography for preoperative planning in minimal-invasive total hip arthroplasty: radiation exposure and cost analysis.

    Huppertz, Alexander; Radmer, Sebastian; Asbach, Patrick; Juran, Ralf; Schwenke, Carsten; Diederichs, Gerd; Hamm, Bernd; Sparmann, Martin


    Computed tomography (CT) was used for preoperative planning of minimal-invasive total hip arthroplasty (THA). 92 patients (50 males, 42 females, mean age 59.5 years) with a mean body-mass-index (BMI) of 26.5 kg/m(2) underwent 64-slice CT to depict the pelvis, the knee and the ankle in three independent acquisitions using combined x-, y-, and z-axis tube current modulation. Arthroplasty planning was performed using 3D-Hip Plan(®) (Symbios, Switzerland) and patient radiation dose exposure was determined. The effects of BMI, gender, and contralateral THA on the effective dose were evaluated by an analysis-of-variance. A process-cost-analysis from the hospital perspective was done. All CT examinations were of sufficient image quality for 3D-THA planning. A mean effective dose of 4.0 mSv (SD 0.9 mSv) modeled by the BMI (p<0.0001) was calculated. The presence of a contralateral THA (9/92 patients; p=0.15) and the difference between males and females were not significant (p=0.08). Personnel involved were the radiologist (4 min), the surgeon (16 min), the radiographer (12 min), and administrative personnel (4 min). A CT operation time of 11 min and direct per-patient costs of 52.80 € were recorded. Preoperative CT for THA was associated with a slight and justifiable increase of radiation exposure in comparison to conventional radiographs and low per-patient costs.

  13. Computed tomography for preoperative planning in minimal-invasive total hip arthroplasty: Radiation exposure and cost analysis

    Huppertz, Alexander, E-mail: [Imaging Science Institute Charite Berlin, Robert-Koch-Platz 7, D-10115 Berlin (Germany); Department of Radiology, Medical Physics, Charite-University Hospitals of Berlin, Chariteplatz 1, D-10117 Berlin (Germany); Radmer, Sebastian, E-mail: [Department of Orthopedic Surgery and Rheumatology, Immanuel-Krankenhaus, Koenigstr. 63, D-14109, Berlin (Germany); Asbach, Patrick, E-mail: [Department of Radiology, Medical Physics, Charite-University Hospitals of Berlin, Chariteplatz 1, D-10117 Berlin (Germany); Juran, Ralf, E-mail: [Department of Radiology, Medical Physics, Charite-University Hospitals of Berlin, Chariteplatz 1, D-10117 Berlin (Germany); Schwenke, Carsten, E-mail: [Biostatistician, Scossis Statistical Consulting, Zeltinger Str. 58G, D-13465 Berlin (Germany); Diederichs, Gerd, E-mail: [Department of Radiology, Medical Physics, Charite-University Hospitals of Berlin, Chariteplatz 1, D-10117 Berlin (Germany); Hamm, Bernd, E-mail: [Department of Radiology, Medical Physics, Charite-University Hospitals of Berlin, Chariteplatz 1, D-10117 Berlin (Germany); Sparmann, Martin, E-mail: [Department of Orthopedic Surgery and Rheumatology, Immanuel-Krankenhaus, Koenigstr. 63, D-14109, Berlin (Germany)


    Computed tomography (CT) was used for preoperative planning of minimal-invasive total hip arthroplasty (THA). 92 patients (50 males, 42 females, mean age 59.5 years) with a mean body-mass-index (BMI) of 26.5 kg/m{sup 2} underwent 64-slice CT to depict the pelvis, the knee and the ankle in three independent acquisitions using combined x-, y-, and z-axis tube current modulation. Arthroplasty planning was performed using 3D-Hip Plan (Symbios, Switzerland) and patient radiation dose exposure was determined. The effects of BMI, gender, and contralateral THA on the effective dose were evaluated by an analysis-of-variance. A process-cost-analysis from the hospital perspective was done. All CT examinations were of sufficient image quality for 3D-THA planning. A mean effective dose of 4.0 mSv (SD 0.9 mSv) modeled by the BMI (p < 0.0001) was calculated. The presence of a contralateral THA (9/92 patients; p = 0.15) and the difference between males and females were not significant (p = 0.08). Personnel involved were the radiologist (4 min), the surgeon (16 min), the radiographer (12 min), and administrative personnel (4 min). A CT operation time of 11 min and direct per-patient costs of 52.80 Euro were recorded. Preoperative CT for THA was associated with a slight and justifiable increase of radiation exposure in comparison to conventional radiographs and low per-patient costs.

  14. Quantification of mitral regurgitation on cardiac computed tomography: comparison with qualitative and quantitative echocardiographic parameters.

    Arnous, Samer


    PURPOSE: To assess whether cardiac computed tomographic angiography (CCTA) can quantify the severity of chronic mitral regurgitation (MR) compared to qualitative and quantitative echocardiographic parameters. MATERIALS AND METHODS: Cardiac computed tomographic angiography was performed in 23 patients (mean +\\/- SD age, 63 +\\/- 16 years; range, 24-86 years) with MR and 20 patients without MR (controls) as determined by transthoracic echocardiography. Multiphasic reconstructions (20 data sets reconstructed at 5% increments of the electrocardiographic gated R-R interval) were used to analyze the mitral valve. Using CCTA planimetry, 2 readers measured the regurgitant mitral orifice area (CCTA ROA) during systole. A qualitative echocardiographic assessment of severity of MR was made by visual assessment of the length of the regurgitant jet. Quantitative echocardiographic measurements included the vena contracta, proximal isovelocity surface area, regurgitant volume, and estimated regurgitant orifice (ERO). Comparisons were performed using the independent t test, and correlations were assessed using the Spearman rank test. RESULTS: All controls and the patients with MR were correctly identified by CCTA. For patients with mild, moderate, or severe MR, mean +\\/- SD EROs were 0.16 +\\/- 0.03, 0.31 +\\/- 0.08, and 0.52 +\\/- 0.03 cm(2) (P < 0.0001) compared with mean +\\/- SD CCTA ROAs 0.09 +\\/- 0.05, 0.30 +\\/- 0.04, and 0.97 +\\/- 0.26 cm(2) (P < 0.0001), respectively. When echocardiographic measurements were graded qualitatively as mild, moderate, or severe, strong correlations were seen with CCTA ROA (R = 0.89; P < 0.001). When echocardiographic measurements were graded quantitatively, the vena contracta and the ERO showed modest correlations with CCTA ROA (0.48 and 0.50; P < 0.05 for both). Neither the proximal isovelocity surface area nor the regurgitant volume demonstrated significant correlations with CCTA ROA. CONCLUSIONS: Single-source 64-slice CCTA provides a

  15. Comparison between MDCT and Grayscale IVUS in a Quantitative Analysis of Coronary Lumen in Segments with or without Atherosclerotic Plaques

    Falcão, João L. A. A.; Falcão, Breno A. A. [Heart Institute (InCor), University of São Paulo Medical School (USP), São Paulo, SP (Brazil); Gurudevan, Swaminatha V. [Cedars-Sinai Heart Institute, Los Angeles, California, USA (United States); Campos, Carlos M.; Silva, Expedito R.; Kalil-Filho, Roberto; Rochitte, Carlos E.; Shiozaki, Afonso A.; Coelho-Filho, Otavio R.; Lemos, Pedro A. [Heart Institute (InCor), University of São Paulo Medical School (USP), São Paulo, SP (Brazil)


    The diagnostic accuracy of 64-slice MDCT in comparison with IVUS has been poorly described and is mainly restricted to reports analyzing segments with documented atherosclerotic plaques. We compared 64-slice multidetector computed tomography (MDCT) with gray scale intravascular ultrasound (IVUS) for the evaluation of coronary lumen dimensions in the context of a comprehensive analysis, including segments with absent or mild disease. The 64-slice MDCT was performed within 72 h before the IVUS imaging, which was obtained for at least one coronary, regardless of the presence of luminal stenosis at angiography. A total of 21 patients were included, with 70 imaged vessels (total length 114.6 ± 38.3 mm per patient). A coronary plaque was diagnosed in segments with plaque burden > 40%. At patient, vessel, and segment levels, average lumen area, minimal lumen area, and minimal lumen diameter were highly correlated between IVUS and 64-slice MDCT (p < 0.01). However, 64-slice MDCT tended to underestimate the lumen size with a relatively wide dispersion of the differences. The comparison between 64-slice MDCT and IVUS lumen measurements was not substantially affected by the presence or absence of an underlying plaque. In addition, 64-slice MDCT showed good global accuracy for the detection of IVUS parameters associated with flow-limiting lesions. In a comprehensive, multi-territory, and whole-artery analysis, the assessment of coronary lumen by 64-slice MDCT compared with coronary IVUS showed a good overall diagnostic ability, regardless of the presence or absence of underlying atherosclerotic plaques.

  16. Quantification of Global Left Ventricular Function: Comparison of Multidetector Computed Tomography and Magnetic Resonance Imaging. A Meta-analysis and Review of the Current Literature

    Vleuten, P.A. van der; Willems, T.P.; Goette, M.J.; Tio, R.A.; Greuter, M.J.; Zijlstra, F.; Oudkerk, M. [Univ. Medical Centre Groningen (Netherlands). Depts. of Cardiology and Radiology


    Cardiac morbidity and mortality are closely related to cardiac volumes and global left ventricular (LV) function, expressed as left ventricular ejection fraction. Accurate assessment of these parameters is required for the prediction of prognosis in individual patients as well as in entire cohorts. The current standard of reference for left ventricular function is analysis by short-axis magnetic resonance imaging. In recent years, major extensive technological improvements have been achieved in computed tomography. The most marked development has been the introduction of the multidetector CT (MDCT), which has significantly improved temporal and spatial resolutions. In order to assess the current status of MDCT for analysis of LV function, the current available literature on this subject was reviewed. The data presented in this review indicate that the global left ventricular functional parameters measured by contemporary multi-detector row systems combined with adequate reconstruction algorithms and post-processing tools show a narrow diagnostic window and are interchangeable with those obtained by MRI.

  17. Detection of Small Hepatocellular Carcinoma with Multi- detector Row CT:Effect of Iodine Concentration of Contrast Material%多排螺旋CT增强扫描对比剂浓度对小肝癌检出率的影响



      目的:通过多排螺旋CT动脉期及门脉期增强扫描,以评估对比剂浓度对小肝癌(≤3cm)检出率的影响.方法:95例肝癌患者随机分为2组行多排螺旋CT肝脏平扫及动脉期、门脉期增强扫描,其中1组(48例)注射碘帕醇370mg I/ml(1.5ml/kg),另外1组(47例)注射碘帕醇300mg I/ml(1.85ml/kg),均于30秒注射完毕.扫描后图像由放射科医生阅片并与病理结果进行对比,统计分析2组≤3cm的肝癌病灶的诊断敏感性.结果:95例患者中共证实有259个肝癌病灶,其中101个≤3cm.对于≤3cm的病灶动脉期370mg I/ml组诊断敏感性高于300mg I/ml组,差别有统计学意义;在门脉期2组病人的诊断敏感性无显著性差异.结论:高浓密度对比剂在动脉期可提高小肝癌(≤3cm)的检出率.%  Objective:To evaluate the effect of iodine concentration of contrast material on detection of small hepatocellular carcinoma (SHCC) with multi-detector row CT by using arterial phase and portal venous phase enhanced scanning.Methods:Ninety-five patients with HCC were examined by hepatic plain CT and contrast-enhanced CT including arterial phase (AP) and hepatic parenchymal phase (HPP) scanning prospectively. Patients were randomized into two groups to receive Iopamidol 370 mg I/ml (48 patients) (1.5 ml/kg body weight) and 300 mg I/ml (47 patients) (1.85 ml/kg body weight) respectively with a fixed injection duration of 30 seconds. The images were interpreted by radiologists and the CT results were compared with the pathological results. The detection sensitivity for small tumors (≤3 cm) and iodine concentration groups were calculated and analyzed.Results:A total of 259 lesions were detected with 101 ≤3 cm in size. For AP, the sensitivity of Iopamidol 370 mg I/ml group was significantly higher than Iopamidol 300 mg I/ml. For HPP, there were no significant differences between groups. Conclusions:High iodine concentration contrast material

  18. 多排螺旋CT双动脉期增强扫描对比剂浓度对肝癌检出率的影响%Detection of Hepatocellular Carcinoma with Multi - detector Row CT by Using Double- arterial Phase Enhanced Scanning: Effect of Iodine Concentration of Contrast Material

    周建收; 宦怡; 景建梅


    目的:通过多排螺旋CT双动脉期及门脉期增强扫描,以评估对比剂浓度对肝癌检出率的影响.方法:95例肝癌患者随机分为两组行多排螺旋CT肝脏平扫及双动脉期、门脉期增强扫描,其中一组(48例)注射碘帕醇370 mgI/ml( 1.5 ml/kg),另外一组(47例)注射碘帕醇300 mgI/ml (1.85ml/kg),均于30 s注射完毕.扫描后图像由放射科医生阅片并与病理结果进行对比,统计分析两组患者> 2cm及≤2cm的肝癌病灶的诊断敏感性.结果:95例患者中共证实有259个肝癌病灶,其中87个≤2cm,172个>2cm.对于≤2cm的病灶及所有病灶动脉早期及晚期370 mgI/ml组诊断敏感性高于300 mgI/ml组,差别有统计学意义;在门脉期两组患者的诊断敏感性无显著性差异.结论:高浓密度对比剂在动脉早期、晚期可提高肝癌的检出率,特别是对于较小的肝癌病灶(≤2cm).%Purpose: To evaluate the effect of iodine concentration of contrast material on detection of hepatocellular carcinoma (HCC) with multi - detector row CT by using double - arterial phase and portal venous phase enhanced scanning. Methods: Ninety - five patients with HCC were examined by hepatic plain CT and contrast - enhanced CT including early arterial phase(EAP), late arterial phase (LAP) and hepatic parenchymal phase (HPP) scanning prospectively. Patients were randomized into two groups to receive Iopamidol 370 mgl/ml (48 patients, 1.5 ml/kg body weight) and 300 mg I/ml (47 patients, 1.85 ml/ kg body weight) respectively with a fixed injection duration of 30 seconds. The images were interpreted by radiologists and the CT results were compared with the pathological results. The detection sensitivity for tumors of two size categories (=£ 2 cm or > 2 cm) and iodine concentration groups were calculated and analyzed.Results: A total of 259 lesions were detected with 87 less than 2 cm in size and 172 larger than 2cm in size.For EAP and LAP, the sensitivity of Iopamidol 370

  19. Current role of cardiac and extra-cardiac pathologies in clinically indicated cardiac computed tomography with emphasis on status before pulmonary vein isolation

    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


    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.)

  20. Computer Music

    Cook, Perry R.

    This chapter covers algorithms, technologies, computer languages, and systems for computer music. Computer music involves the application of computers and other digital/electronic technologies to music composition, performance, theory, history, and the study of perception. The field combines digital signal processing, computational algorithms, computer languages, hardware and software systems, acoustics, psychoacoustics (low-level perception of sounds from the raw acoustic signal), and music cognition (higher-level perception of musical style, form, emotion, etc.).


    Lesley Ann Cala


    Full Text Available Development of multislice CT (MSCT scanners since 1998 has resulted in submillimetre thick slices being able to be acquired, without increasing the radiation dose to the patient. Although the incident x-ray beam is widened in the slice thickness direction (Z-direction, the emergent x-rays fall upon multiple rows of small detectors. This means data can be collected simultaneously for more than one slice per rotation of the x-ray tube. For example, the dose received by the patient will be the same for four thin slices of 2.5 mm, as for one slice of 10 mm thickness. A 64-slice MSCT can create 0.625 mm thick slices. This leads to high diagnostic value in the detection of small abnormalities in stroke patients and in the reconstruction of data from CT angiography (CTA of the brain.

  2. SU-E-I-28: Evaluating the Organ Dose From Computed Tomography Using Monte Carlo Calculations

    Ono, T; Araki, F [Faculty of Life Sciences, Kumamoto University, Kumamoto (Japan)


    Purpose: To evaluate organ doses from computed tomography (CT) using Monte Carlo (MC) calculations. Methods: A Philips Brilliance CT scanner (64 slice) was simulated using the GMctdospp (IMPS, Germany) based on the EGSnrc user code. The X-ray spectra and a bowtie filter for MC simulations were determined to coincide with measurements of half-value layer (HVL) and off-center ratio (OCR) profile in air. The MC dose was calibrated from absorbed dose measurements using a Farmer chamber and a cylindrical water phantom. The dose distribution from CT was calculated using patient CT images and organ doses were evaluated from dose volume histograms. Results: The HVLs of Al at 80, 100, and 120 kV were 6.3, 7.7, and 8.7 mm, respectively. The calculated HVLs agreed with measurements within 0.3%. The calculated and measured OCR profiles agreed within 3%. For adult head scans (CTDIvol) =51.4 mGy), mean doses for brain stem, eye, and eye lens were 23.2, 34.2, and 37.6 mGy, respectively. For pediatric head scans (CTDIvol =35.6 mGy), mean doses for brain stem, eye, and eye lens were 19.3, 24.5, and 26.8 mGy, respectively. For adult chest scans (CTDIvol=19.0 mGy), mean doses for lung, heart, and spinal cord were 21.1, 22.0, and 15.5 mGy, respectively. For adult abdominal scans (CTDIvol=14.4 mGy), the mean doses for kidney, liver, pancreas, spleen, and spinal cord were 17.4, 16.5, 16.8, 16.8, and 13.1 mGy, respectively. For pediatric abdominal scans (CTDIvol=6.76 mGy), mean doses for kidney, liver, pancreas, spleen, and spinal cord were 8.24, 8.90, 8.17, 8.31, and 6.73 mGy, respectively. In head scan, organ doses were considerably different from CTDIvol values. Conclusion: MC dose distributions calculated by using patient CT images are useful to evaluate organ doses absorbed to individual patients.

  3. Grid Computing


    A computing grid interconnects resources such as high performancecomputers, scientific databases, and computercontrolledscientific instruments of cooperating organizationseach of which is autonomous. It precedes and is quitedifferent from cloud computing, which provides computingresources by vendors to customers on demand. In this article,we describe the grid computing model and enumerate themajor differences between grid and cloud computing.

  4. Computer Virus



    If you work with a computer,it is certain that you can not avoid dealing, with at least one computer virus.But how much do you know about it? Well,actually,a computer virus is not a biological' one as causes illnesses to people.It is a kind of computer program

  5. Analog computing

    Ulmann, Bernd


    This book is a comprehensive introduction to analog computing. As most textbooks about this powerful computing paradigm date back to the 1960s and 1970s, it fills a void and forges a bridge from the early days of analog computing to future applications. The idea of analog computing is not new. In fact, this computing paradigm is nearly forgotten, although it offers a path to both high-speed and low-power computing, which are in even more demand now than they were back in the heyday of electronic analog computers.

  6. Computational composites

    Vallgårda, Anna K. A.; Redström, Johan


    Computational composite is introduced as a new type of composite material. Arguing that this is not just a metaphorical maneuver, we provide an analysis of computational technology as material in design, which shows how computers share important characteristics with other materials used in design...... and architecture. We argue that the notion of computational composites provides a precise understanding of the computer as material, and of how computations need to be combined with other materials to come to expression as material. Besides working as an analysis of computers from a designer’s point of view......, the notion of computational composites may also provide a link for computer science and human-computer interaction to an increasingly rapid development and use of new materials in design and architecture....

  7. Computational chemistry


    Computational chemistry has come of age. With significant strides in computer hardware and software over the last few decades, computational chemistry has achieved full partnership with theory and experiment as a tool for understanding and predicting the behavior of a broad range of chemical, physical, and biological phenomena. The Nobel Prize award to John Pople and Walter Kohn in 1998 highlighted the importance of these advances in computational chemistry. With massively parallel computers ...

  8. Effective dose estimates for cone beam computed tomography in interventional radiology

    Kwok, Y.M.; Irani, F.G.; Tay, K.H.; Yang, C.C.; Padre, C.G.; Tan, B.S. [Singapore General Hospital, Department of Diagnostic Radiology, Singapore (Singapore)


    To compare radiation doses in cone beam computed tomography (CBCT) with those of multi-detector computed tomography (MDCT) using manufacturers' standard protocols. Dose-levels in head and abdominal imaging were evaluated using a dosimetric phantom. Effective dose estimates were performed by placing thermoluminescent dosimeters in the phantom. Selected protocols for two CBCT systems and comparable protocols for one MDCT system were evaluated. Organ doses were measured and effective doses derived by applying the International Commission on Radiological Protection 2007 tissue weighting factors. Effective doses estimated for the head protocol were 4.4 and 5.4 mSv for the two CBCT systems respectively and 4.3 mSv for MDCT. Eye doses for one CBCT system and MDCT were comparable (173.6 and 148.4 mGy respectively) but significantly higher compared with the second CBCT (44.6 mGy). Two abdominal protocols were evaluated for each system; the effective doses estimated were 15.0 and 18.6 mSv, 25.4 and 37.0 mSv, and 9.8 and 13.5 mSv, respectively, for each of the CBCT and MDCT systems. The study demonstrated comparable dose-levels for CBCT and MDCT systems in head studies, but higher dose levels for CBCT in abdominal studies. There was a significant difference in eye doses observed between the CBCT systems. (orig.)

  9. Perfusion computed tomography for diffuse liver diseases; Perfusions-CT bei diffusen Lebererkrankungen

    Schmidt, S.A.; Juchems, M.S. [Universitaetsklinikum Ulm, Klinik fuer Diagnostische und Interventionelle Radiologie, Ulm (Germany)


    Perfusion computed tomography (CT) has its main application in the clinical routine diagnosis of neuroradiological problems. Polyphase multi-detector spiral computed tomography is primarily used in liver diagnostics. The use of perfusion CT is also possible for the diagnostics and differentiation of diffuse hepatic diseases. The differentiation between cirrhosis and cirrhosis-like parenchymal changes is possible. It also helps to detect early stages of malignant tumors. However, there are some negative aspects, particularly that of radiation exposure. This paper summarizes the technical basics and possible applications of perfusion CT in cases of diffuse liver disease and weighs up the advantages and disadvantages of the examinations. (orig.) [German] Die Perfusions-CT hat ihren hauptsaechlichen Stellenwert bislang in der klinischen Routinediagnostik bei neuroradiologische Fragestellungen. In der Leberdiagnostik kommt v. a. die mehrphasige Multidetektor-Spiral-CT-Untersuchung zum Einsatz. Die Anwendung der Perfusions-CT ist auch bei der Diagnostik und Differenzierung diffuser Lebererkrankungen moeglich. Die Unterscheidung zwischen einer Leberzirrhose und zirrhoseaehnlichen Parenchymveraenderungen ist mit der Perfusions-CT moeglich. Ebenso liefert sie einen wertvollen Beitrag zur Diagnostik bei der Frueherkennung entstehender maligner Herdbefunde. Diesen Vorteilen stehen jedoch auch einige negative Aspekte gegenueber, insbesondere die relativ hohe Strahlenexposition. Die vorliegende Arbeit soll einen Ueberblick ueber die technischen Grundlagen und die Anwendungsmoeglichkeiten der Perfusions-CT bei diffusen Lebererkrankungen geben sowie die Vor- und Nachteile der Untersuchung gegeneinander abwaegen. (orig.)

  10. Automated detection of lung nodules in low-dose computed tomography

    Cascio, D. [Dipt. di Fisica e Tecnologie Relative, Univ. di Palermo (Italy); Cheran, S.C. [Dipt. di Fisica, Univ. di Genova (Italy); Ist. Nazionale di Fisica Nucleare, Sezione di Torino (Italy); Chincarini, A. [Ist. Nazionale di Fisica Nucleare, Sezione di Genova (Italy); De Nunzio, G. [Dipt. di Scienza dei Materiali, Univ. di Lecce (Italy); Delogu, P.; Fantacci, M.E. [Dipt. di Fisica, Univ. di Pisa (Italy); Ist. Nazionale di Fisica Nucleare, Sezione di Pisa (Italy); Gargano, G. [Dipt. Interateneo di Fisica M. Merlin, Univ. di Bari (Italy); Ist. Nazionale di Fisica Nucleare, Sezione di Bari (Italy); Gori, I.; Retico, A. [Ist. Nazionale di Fisica Nucleare, Sezione di Pisa (Italy); Masala, G.L. [Struttura Dipartimentale di Matematica e Fisica, Univ. di Sassari (Italy); Ist. Nazionale di Fisica Nucleare, Sezione di Cagliari (Italy); Preite Martinez, A. [Centro Studi e Ricerche Enrico Fermi, Roma (Italy); Santoro, M. [Dipt. di Scienze Fisiche, Univ. di Napoli (Italy); Spinelli, C. [Unita Operativa Radiodiagnostica 2, Azienda Ospedaliera Universitaria Pisana, Pisa (Italy); Tarantino, T. [Divisione di Radiologia Diagnostica e Interventistica del Dipt. di Oncologia, Trapianti e Nuove Tecnologie in Medicina, Univ. di Pisa (Italy)


    A computer-aided detection (CAD) system for the identification of pulmonary nodules in low-dose multi-detector computed-tomography (CT) images has been developed in the framework of the MAGIC-5 Italian project. One of the main goals of this project is to build a distributed database of lung CT scans in order to enable automated image analysis through a data and cpu GRID infrastructure. The basic modules of our lung-CAD system, consisting in a 3D dot-enhancement filter for nodule detection and a neural classifier for false-positive finding reduction, are described. The system was designed and tested for both internal and sub-pleural nodules. The database used in this study consists of 17 low-dose CT scans reconstructed with thin slice thickness ({proportional_to}300 slices/scan). The preliminary results are shown in terms of the FROC analysis reporting a good sensitivity (85% range) for both internal and sub-pleural nodules at an acceptable level of false positive findings (1-9 FP/scan); the sensitivity value remains very high (75% range) even at 1-6 FP/scan. (orig.)

  11. Duality Computing in Quantum Computers

    LONG Gui-Lu; LIU Yang


    In this letter, we propose a duality computing mode, which resembles particle-wave duality property when a quantum system such as a quantum computer passes through a double-slit. In this mode, computing operations are not necessarily unitary. The duality mode provides a natural link between classical computing and quantum computing. In addition, the duality mode provides a new tool for quantum algorithm design.

  12. Computational manufacturing


    This paper presents a general framework for computational manufacturing. The methodology of computational manufacturing aims at integrating computational geometry, machining principle, sensor information fusion, optimization, computational intelligence and virtual prototyping to solve problems of the modeling, reasoning, control, planning and scheduling of manufacturing processes and systems. There are three typical problems in computational manufacturing, i.e., scheduling (time-domain), geometric reasoning (space-domain) and decision- making (interaction between time-domain and space-domain). Some theoretical fundamentals of computational manufacturing are also discussed.

  13. 进展期非小细胞肺癌的首过法CT灌注可重复性研究%Advanced NSCLC First Pass Perfusion at 64-slice CT: Reproducibility of Volume-based Quantitative Measurement

    单飞; 张志勇; 曾蒙苏; 胡洁; 白春学


    背景与目的 本研究旨在探讨进展期非小细胞肺癌(non-small cell lung cancer, NSCLC)首过法CT灌注(CT perfusion, CTP)的可重复性.方法 在本院行首过法CTP检查(8×5 mm层厚),且经病理证实的进展期NSCLC患者14例,肿瘤最大径≤3 cm及>3 cm各7例,均在24 h内行第二次CTP扫描.采用组内相关系数(intraclass correlationcoefficient, ICC)及Bland-Altman法评价CTP检查的可重复性.结果 两组进展期NSCLC的血流速度(blood flow, BF)、血容量(blood volume, BV)及表面通透性(permeability surface area product, PS)值的ICC均>0.75;对比剂的平均通过时间(mean transit time, MTT)的ICC均3 cm组的BF、BV、MTT及PS的RC及RC值95%变化区间依次为46%(-48%-45%)、30%(-33%-26%)、-59%(-54%-64%)、33%(-18%-48%).结论 去卷积法首过法CTP参数BF及BV可重复性较好,用于评价进展期NSCLC抗血管生成治疗疗效时,可根据肿瘤大小,应用不同的可重复性标准区别对待.

  14. Value of 64-slice spiral CT angiography in diagnosis of Takayasu's arteritis%64排螺旋CT血管成像在大动脉炎诊断中的价值

    徐崇明; 赵晓军


    目的 探讨64排螺旋CT血管成像(CTA)在大动脉炎临床诊断中的应用价值.方法 对临床拟诊大动脉炎的9例患者进行64排螺旋CT血管成像,图像后处理方法包括多平面重组(MPR)、最大密度投影(MIP)、容积再现(VR)、曲面重组(CPR)及血管分析,显示受累血管的部位、范围及程度.结果 64排螺旋CT血管成像清楚显示受累动脉不同程度的管壁增厚,管腔狭窄或闭塞,管腔狭窄具有向心性的特点,部分伴狭窄后扩张.后处理图像可以直观显示受累大血管及其分支血管的狭窄程度或闭塞情况以及侧支血管形成情况,依据Lupi-Herrea分类法包括I型5例,Ⅱ型1例,Ⅲ型3例,CT结果均与其临床表现相符.结论 64排CTA可清晰地显示大动脉炎累及主动脉及其分支的管壁变化,三维重建可更直观地显示病变的程度和范围,可以作为此病的首选影像学检查方法.

  15. Evaluation of coronary artery in-stent restenosis using 64-slice CT%64层螺旋CT评价冠状动脉支架内再狭窄的价值

    刘新; 李颖; 杨立; 赵锡海; 王新疆; 赵绍宏; 张玉霄; 蔡祖龙


    目的 评介64层螺旋CT诊断冠状动脉支架内再狭窄(ISR)的临床价值.方法 采用64层螺旋CT对14例冠状动脉支架置入术后的患者(共37个支架)进行CT冠状动脉成像(CTA).在CTA上,通过肉眼观察和测量支架内CT值两种方法诊断ISR.以冠状动脉造影(ISR≥50%)为标准,计算并比较两种方法诊断ISR的准确性.结果 37个支架中,CCA检出ISR(≥50%)11个,正常(包括ISR<50%)26个.与CCA对照,CTA肉眼观察法正确诊断ISR 2个,正常18个,CT值测量法则分别正确诊断ISR 3个,正常21个.两种方法诊断ISR的敏感性、特异性、阳性预测值和阴性预测值分别为18%、69%、20%、67%和27%、81%、38%、72%.两种方法各项准确性指标之间差异均无统计学意义(P>0.05).结论 64层螺旋CT诊断ISR十分困难,但对排除ISR有一定的作用.

  16. 64排VCT诊断心脏血管肉瘤1例并文献复习%64-slice CT Diagnosis of Cardiac Angiosarcoma:A Report and Literature Review

    潘元威; 高剑波; 周志刚; 郭华; 董军强


    @@ 原发性心脏恶性肿瘤临床上十分少见,易被误诊或延期诊断.本文结合CT引导下穿刺确诊心脏血管肉瘤1例,并复习相关文献,将心脏恶性肉瘤的影像学诊断作以下总结. 患者,男,29岁.以"咳嗽伴右侧胸痛,活动后心慌、气短、胸闷1 d"为主诉至当地医院,查心电图示:①广泛前壁T波改变.②R波V5振幅增高.心脏超声提示:心包及右心房实性占位,二尖瓣轻度脱垂.为求进一步诊治来本院,以"心脏占位"收入.

  17. Diagnosis of 64 Slice Spiral CT and MPR Techniques in Silico Tuberculosis%64排螺旋CT及MPR技术对肺尘埃沉着病合并肺结核的诊断



    目的:探讨64排螺旋CT及其MPR技术对肺尘埃沉着病合并肺结核的诊断价值。方法对50例肺尘埃沉着病患者进行胸部64排螺旋CT检查,得到胸部轴位(层厚1mm)及MPR图像,分析肺尘埃沉着病合并肺结核CT表现,对早期发现肺尘埃沉着病合并结核有重要价值。结果肺尘埃沉着病合并血行播散型肺结核1例,继发性肺结核48例,其中渗出浸润为主32例,占66%;干酪为主型6例,占12.5%;空洞为主型10例,占20.8%;肺尘埃沉着病合并结核性胸膜炎1例,占0.2%。结论64排螺旋CT及MPR技术对肺尘埃沉着病合并结核的诊断优势明显。MPR技术对胸部整体情况能多方位,直观,清晰和形象地显示,特别是晚期肺尘埃沉着病合并结核早期诊断提供较为可靠依据。%Objective  To explore the diagnostic value of 64 slice spiral CT and MPR technology combined with pulmonary tuberculosis of silicosis. Methods Chest 64 slice spiral CT examination of 50 cases of patients with silicosis, get the chest axis (thickness 1) and MPR image, analysis of silicosis complicated with tuberculosis CT manifestations of silicosis complicated with tuberculosis, early detection is of important value. Results  1 cases of silicosis complicated with hematogenous disseminated pulmonary tuberculosis,48 patients with secondary pulmonary tuberculosis, which exude inifltration in 32 cases, accounting for 66%; cheese based type in 6 cases, accounting for 12.5%; the main cavity type in 10 cases, accounting for 20.8%; 1 cases of silicosis complicated with tuberculosis pleurisy, accounted for 0.2%. Conclusion  Diagnostic advantage of conclusion 64 slice spiral CT and MPR technology on silicosis patients complicated with tuberculosis. MPR technology on the chest overall situation can be multi-dimensional, intuitive, clear and vivid display, especially to provide reliable evidences for early diagnosis of advanced silicosis patients complicated with tuberculosis.

  18. Low-dose Imaging Technology and Its Application under New 64-Slice CT Generation%后64排CT时代的低剂量成像技术和应用现状

    陈星; 张唯唯; 张华


    To keep radiation dose as low as reasonably low remains the most important and challenging strategy for the potential risk of cancer induction from CT scan. This paper reviews the latest techniques to effectively reduce the radiation dose and discuss the low dose management strategy for routine clinical applications.%维持CT扫描过程中的放射剂量在一个合理的低范围,从而减少致癌因素,是目前最重要和最具挑战性的课题.本文重点介绍了最新有效降低放射剂量的技术,以及讨论日常临床应用中有效低放射剂量的管理策略.

  19. 64-slice spiral CT and image post-processing technique in diagnosis of SAPHO syndrome%64排螺旋CT及其后处理技术对SAPHO综合征的诊断

    吕国义; 魏少奎; 杨实真; 李华中; 喻汉华


    目的 探讨64排螺旋CT及其后处理技术对SAPHO综合征的诊断.方法 观察分析5例SAPHO患者64排螺旋CT平扫及多平面重建、曲面重建、表面遮盖显示、容积再现图像.结果 5例SAPHO患者出现双侧锁骨近中段、第1肋骨近端及胸骨膨大,骨质增生硬化,胸-肋-锁关节面侵蚀、硬化、韧带骨化、关节间隙狭窄或骨性融合;3例患者胸椎、腰椎、颈椎表现为椎角骨质侵蚀硬化、椎间隙变窄、骨硬化、椎旁韧带骨化;2例患者发生单侧骶髂关节炎,骶髂关节髂骨面硬化,骶髂关节间隙变窄.结论 64排螺旋CT平扫及后处理技术可以良好地显示SAPHO患者胸肋锁骨区、脊柱及骶髂关节的骨炎、骨肥厚、滑膜炎的特征性改变,对SAPHO综合征诊断具有较高的应用价值.

  20. Computer Algebra.

    Pavelle, Richard; And Others


    Describes the nature and use of computer algebra and its applications to various physical sciences. Includes diagrams illustrating, among others, a computer algebra system and flow chart of operation of the Euclidean algorithm. (SK)

  1. Quantum computing

    Li, Shu-Shen; Long, Gui-lu; Bai, Feng-Shan; Feng, Song-Lin; Zheng, Hou-Zhi


    Quantum computing is a quickly growing research field. This article introduces the basic concepts of quantum computing, recent developments in quantum searching, and decoherence in a possible quantum dot realization.

  2. Computational dosimetry

    Siebert, B.R.L.; Thomas, R.H.


    The paper presents a definition of the term ``Computational Dosimetry`` that is interpreted as the sub-discipline of computational physics which is devoted to radiation metrology. It is shown that computational dosimetry is more than a mere collection of computational methods. Computational simulations directed at basic understanding and modelling are important tools provided by computational dosimetry, while another very important application is the support that it can give to the design, optimization and analysis of experiments. However, the primary task of computational dosimetry is to reduce the variance in the determination of absorbed dose (and its related quantities), for example in the disciplines of radiological protection and radiation therapy. In this paper emphasis is given to the discussion of potential pitfalls in the applications of computational dosimetry and recommendations are given for their avoidance. The need for comparison of calculated and experimental data whenever possible is strongly stressed.

  3. Contextual Computing

    Porzel, Robert


    This book uses the latest in knowledge representation and human-computer interaction to address the problem of contextual computing in artificial intelligence. It uses high-level context to solve some challenging problems in natural language understanding.

  4. Green Computing

    K. Shalini


    Full Text Available Green computing is all about using computers in a smarter and eco-friendly way. It is the environmentally responsible use of computers and related resources which includes the implementation of energy-efficient central processing units, servers and peripherals as well as reduced resource consumption and proper disposal of electronic waste .Computers certainly make up a large part of many people lives and traditionally are extremely damaging to the environment. Manufacturers of computer and its parts have been espousing the green cause to help protect environment from computers and electronic waste in any way.Research continues into key areas such as making the use of computers as energy-efficient as Possible, and designing algorithms and systems for efficiency-related computer technologies.

  5. Computable models

    Turner, Raymond


    Computational models can be found everywhere in present day science and engineering. In providing a logical framework and foundation for the specification and design of specification languages, Raymond Turner uses this framework to introduce and study computable models. In doing so he presents the first systematic attempt to provide computational models with a logical foundation. Computable models have wide-ranging applications from programming language semantics and specification languages, through to knowledge representation languages and formalism for natural language semantics. They are al

  6. Computing fundamentals introduction to computers

    Wempen, Faithe


    The absolute beginner's guide to learning basic computer skills Computing Fundamentals, Introduction to Computers gets you up to speed on basic computing skills, showing you everything you need to know to conquer entry-level computing courses. Written by a Microsoft Office Master Instructor, this useful guide walks you step-by-step through the most important concepts and skills you need to be proficient on the computer, using nontechnical, easy-to-understand language. You'll start at the very beginning, getting acquainted with the actual, physical machine, then progress through the most common

  7. Quantum Computing for Computer Architects

    Metodi, Tzvetan


    Quantum computers can (in theory) solve certain problems far faster than a classical computer running any known classical algorithm. While existing technologies for building quantum computers are in their infancy, it is not too early to consider their scalability and reliability in the context of the design of large-scale quantum computers. To architect such systems, one must understand what it takes to design and model a balanced, fault-tolerant quantum computer architecture. The goal of this lecture is to provide architectural abstractions for the design of a quantum computer and to explore

  8. Computational Composites

    Vallgårda, Anna K. A.

    of the new microprocessors and network technologies. However, the understanding of the computer represented within this program poses a challenge for the intentions of the program. The computer is understood as a multitude of invisible intelligent information devices which confines the computer as a tool...

  9. Distributed Computing.

    Ryland, Jane N.


    The microcomputer revolution, in which small and large computers have gained tremendously in capability, has created a distributed computing environment. This circumstance presents administrators with the opportunities and the dilemmas of choosing appropriate computing resources for each situation. (Author/MSE)

  10. Phenomenological Computation?

    Brier, Søren


    Open peer commentary on the article “Info-computational Constructivism and Cognition” by Gordana Dodig-Crnkovic. Upshot: The main problems with info-computationalism are: (1) Its basic concept of natural computing has neither been defined theoretically or implemented practically. (2. It cannot en...

  11. Computational Complexity

    J. A. Tenreiro Machado


    Full Text Available Complex systems (CS involve many elements that interact at different scales in time and space. The challenges in modeling CS led to the development of novel computational tools with applications in a wide range of scientific areas. The computational problems posed by CS exhibit intrinsic difficulties that are a major concern in Computational Complexity Theory. [...

  12. Computer Ease.

    Drenning, Susan; Getz, Lou


    Computer Ease is an intergenerational program designed to put an Ohio elementary school's computer lab, software library, staff, and students at the disposal of older adults desiring to become computer literate. Three 90-minute instructional sessions allow seniors to experience 1-to-1 high-tech instruction by enthusiastic, nonthreatening…

  13. Real-time three-dimensional echocardiographic left ventricular ejection fraction and volumes assessment: comparison with cardiac computed tomography; Comparacao entre a afericao da fracao de ejecao e dos volumes do ventriculo esquerdo, medidos com ecocardiografia tridimensional em tempo real e com tomografia computadorizada ultra-rapida

    Vieira, Marcelo L.C.; Nomura, Cesar H.; Tranchesi Junior, Bernardino; Oliveira, Wercules A. de; Naccarato, Gustavo; Serpa, Bruna S.; Cury, Alexandre; Passos, Rodrigo B.D.; Nobrega, Marcel V. da; Funari, Marcelo B.G.; Pfefermam, Abhaham; Makdisse, Marcia; Fischer, Claudio H.; Morhy, Samira S., E-mail: [Hospital Israelita Albert Einstein, Sao Paulo, SP (Brazil)


    Background and objective: Few studies addressed the comparison between real-time 3D echocardiography (RT3DE) and cardiac computed tomography (CCT) concerning left ventricular ejection fraction and volumes assessment. We sought to compare both techniques regarding left ventricle (LV) ejection fraction function and volumes analysis. Methods: we studied by RT3DE (Philips IE 33, And, MA, USA) and by CCT (Toshiba, 64-slice, Otawara, Japan) 41 consecutive patients (29 males, 58 ± 11 yrs). We analysed by both techniques LVEF, LVEDV, LVESV. RT3DE and CCT data were compared by coefficients of determination (r: Pearson), Bland and Altman test and linear regression, 95% CI. Results: RT3DE data: LVEF ranged from 56.7 to 78.9 % (65.3 + 5.7 ); LVEDV ranged from 49.6 to 178.2 (88 + 27.5) mL; LVESV from 11.4 to 78 ( 33.9 + 13.7) mL. CCT data: LVEF ranged from 53 to 86 % (67.3 + 7.9 ); LVEDV ranged from 51 to 186 (106.4 + 30.7) mL; LVESV from 7 to 72 ( 35.1 + 13.8) mL. Correlations relative to RT3DE and CCT were: LVEF (r: 0. 7877, p<0.0001, 95 % CI 0.6327 to 0.8853 ); LVEDV (r:0.7671, p<0.0001, 95 % CI 0.5974 to 0.8745); LVESV (r: 0.8121, p<0.0001, 95 % CI 0.6659 to 0.8957). Conclusions: it was observed adequate correlation between real-time 3D echocardiography and cardiac computed tomography concerning ejection fraction and volumes assessment. (author)

  14. Computer science

    Blum, Edward K


    Computer Science: The Hardware, Software and Heart of It focuses on the deeper aspects of the two recognized subdivisions of Computer Science, Software and Hardware. These subdivisions are shown to be closely interrelated as a result of the stored-program concept. Computer Science: The Hardware, Software and Heart of It includes certain classical theoretical computer science topics such as Unsolvability (e.g. the halting problem) and Undecidability (e.g. Godel's incompleteness theorem) that treat problems that exist under the Church-Turing thesis of computation. These problem topics explain in

  15. Human Computation

    CERN. Geneva


    What if people could play computer games and accomplish work without even realizing it? What if billions of people collaborated to solve important problems for humanity or generate training data for computers? My work aims at a general paradigm for doing exactly that: utilizing human processing power to solve computational problems in a distributed manner. In particular, I focus on harnessing human time and energy for addressing problems that computers cannot yet solve. Although computers have advanced dramatically in many respects over the last 50 years, they still do not possess the basic conceptual intelligence or perceptual capabilities...

  16. Computer Science Research: Computation Directorate

    Durst, M.J. (ed.); Grupe, K.F. (ed.)


    This report contains short papers in the following areas: large-scale scientific computation; parallel computing; general-purpose numerical algorithms; distributed operating systems and networks; knowledge-based systems; and technology information systems.

  17. Computer sciences

    Smith, Paul H.


    The Computer Science Program provides advanced concepts, techniques, system architectures, algorithms, and software for both space and aeronautics information sciences and computer systems. The overall goal is to provide the technical foundation within NASA for the advancement of computing technology in aerospace applications. The research program is improving the state of knowledge of fundamental aerospace computing principles and advancing computing technology in space applications such as software engineering and information extraction from data collected by scientific instruments in space. The program includes the development of special algorithms and techniques to exploit the computing power provided by high performance parallel processors and special purpose architectures. Research is being conducted in the fundamentals of data base logic and improvement techniques for producing reliable computing systems.

  18. Computer Literacy: Teaching Computer Ethics.

    Troutner, Joanne


    Suggests learning activities for teaching computer ethics in three areas: (1) equal access; (2) computer crime; and (3) privacy. Topics include computer time, advertising, class enrollments, copyright law, sabotage ("worms"), the Privacy Act of 1974 and the Freedom of Information Act of 1966. (JM)

  19. Under-reporting of osteoporotic vertebral fractures on computed tomography

    Williams, Alexandra L. [Department of Radiology, Manchester Royal Infirmary, Oxford Road, Manchester (United Kingdom)], E-mail:; Al-Busaidi, Aisha [Department of Radiology, Manchester Royal Infirmary, Oxford Road, Manchester (United Kingdom)], E-mail:; Sparrow, Patrick J. [Department of Radiology, Manchester Royal Infirmary, Oxford Road, Manchester (United Kingdom)], E-mail:; Adams, Judith E. [Department of Radiology, Manchester Royal Infirmary, Oxford Road, Manchester (United Kingdom); Department of Clinical Radiology, Imaging Science and Biomedical Engineering, Stopford Building, , University of Manchester, Oxford Road, Manchester M13 9PT (United Kingdom)], E-mail:; Whitehouse, Richard W. [Department of Radiology, Manchester Royal Infirmary, Oxford Road, Manchester (United Kingdom)], E-mail:


    Purpose: Osteoporotic vertebral fractures are frequently asymptomatic. They are often not diagnosed clinically or radiologically. Despite this, prevalent osteoporotic vertebral fractures predict future osteoporotic fractures and are associated with increased mortality and morbidity. Appropriate management of osteoporosis can reduce future fracture risk. Fractures on lateral chest radiographs taken for other conditions are frequently overlooked by radiologists. Our aim was to assess the value of computed tomography (CT) in the diagnosis of vertebral fracture and identify the frequency with which significant fractures are missed. Materials and methods: The thoracic CT scans of 100 consecutive male and 100 consecutive female patients over 55 years were reviewed. CT images were acquired on General Electric Lightspeed multi-detector (MD) CT scanners (16 or 32 row) using 1.25 mm slice thickness. Midline sagittal images were reconstructed from the 3D volume images. The presence of moderate (25-40% height loss) or severe (>40% height loss) vertebral fractures between T1 and L1 was determined using an established semi-quantitative method and confirmed by morphological measurement. Results were compared with the formal CT report. Results: Scans of 192 patients were analysed (95 female; 97 male); mean age 70.1 years. Thirty-eight (19.8%) patients had one or more moderate to severe vertebral fractures. Only 5 (13%) were correctly reported as having osteoporotic fractures in the official report. The sensitivity of axial CT images to vertebral fracture was 0.35. Conclusion: Incidental osteoporotic vertebral fractures are under-reported on CT. The sensitivity of axial images in detecting these fractures is poor. Sagittal reformations are strongly recommended to improve the detection rate.

  20. Computer programming and computer systems

    Hassitt, Anthony


    Computer Programming and Computer Systems imparts a "reading knowledge? of computer systems.This book describes the aspects of machine-language programming, monitor systems, computer hardware, and advanced programming that every thorough programmer should be acquainted with. This text discusses the automatic electronic digital computers, symbolic language, Reverse Polish Notation, and Fortran into assembly language. The routine for reading blocked tapes, dimension statements in subroutines, general-purpose input routine, and efficient use of memory are also elaborated.This publication is inten

  1. Organic Computing

    Würtz, Rolf P


    Organic Computing is a research field emerging around the conviction that problems of organization in complex systems in computer science, telecommunications, neurobiology, molecular biology, ethology, and possibly even sociology can be tackled scientifically in a unified way. From the computer science point of view, the apparent ease in which living systems solve computationally difficult problems makes it inevitable to adopt strategies observed in nature for creating information processing machinery. In this book, the major ideas behind Organic Computing are delineated, together with a sparse sample of computational projects undertaken in this new field. Biological metaphors include evolution, neural networks, gene-regulatory networks, networks of brain modules, hormone system, insect swarms, and ant colonies. Applications are as diverse as system design, optimization, artificial growth, task allocation, clustering, routing, face recognition, and sign language understanding.

  2. Quantum Computing

    Steane, A M


    The subject of quantum computing brings together ideas from classical information theory, computer science, and quantum physics. This review aims to summarise not just quantum computing, but the whole subject of quantum information theory. It turns out that information theory and quantum mechanics fit together very well. In order to explain their relationship, the review begins with an introduction to classical information theory and computer science, including Shannon's theorem, error correcting codes, Turing machines and computational complexity. The principles of quantum mechanics are then outlined, and the EPR experiment described. The EPR-Bell correlations, and quantum entanglement in general, form the essential new ingredient which distinguishes quantum from classical information theory, and, arguably, quantum from classical physics. Basic quantum information ideas are described, including key distribution, teleportation, data compression, quantum error correction, the universal quantum computer and qua...

  3. Computer Virus


    Computer viruses are small software programs that are designed to spread from one computerto another and to interfere with computer operation.A virus might delete data on your computer,use your e-mail program to spread itself to othercomputers,or even erase everything on your hard disk.Viruses are most easily spread by attach-ments in e-mail messages or instant messaging messages.That is why it is essential that you never

  4. Fog computing

    Poplštein, Karel


    The purpose of this bachelor's thesis is to address fog computing technology, that emerged as a possible solution for the internet of things requirements and aims to lower latency and network bandwidth by moving a substantial part of computing operation to the network edge. The thesis identifies advantages as well as potential threats and analyses the possible solutions to these problems, proceeding to comparison of cloud and fog computing and specifying areas of use for both of them. Finally...

  5. Characterizing trabecular bone structure for assessing vertebral fracture risk on volumetric quantitative computed tomography

    Nagarajan, Mahesh B.; Checefsky, Walter A.; Abidin, Anas Z.; Tsai, Halley; Wang, Xixi; Hobbs, Susan K.; Bauer, Jan S.; Baum, Thomas; Wismüller, Axel


    While the proximal femur is preferred for measuring bone mineral density (BMD) in fracture risk estimation, the introduction of volumetric quantitative computed tomography has revealed stronger associations between BMD and spinal fracture status. In this study, we propose to capture properties of trabecular bone structure in spinal vertebrae with advanced second-order statistical features for purposes of fracture risk assessment. For this purpose, axial multi-detector CT (MDCT) images were acquired from 28 spinal vertebrae specimens using a whole-body 256-row CT scanner with a dedicated calibration phantom. A semi-automated method was used to annotate the trabecular compartment in the central vertebral slice with a circular region of interest (ROI) to exclude cortical bone; pixels within were converted to values indicative of BMD. Six second-order statistical features derived from gray-level co-occurrence matrices (GLCM) and the mean BMD within the ROI were then extracted and used in conjunction with a generalized radial basis functions (GRBF) neural network to predict the failure load of the specimens; true failure load was measured through biomechanical testing. Prediction performance was evaluated with a root-mean-square error (RMSE) metric. The best prediction performance was observed with GLCM feature `correlation' (RMSE = 1.02 ± 0.18), which significantly outperformed all other GLCM features (p GLCM feature correlation also significantly outperformed MDCTmeasured mean BMD (RMSE = 1.11 ± 0.17) (pGLCM-derived texture features.

  6. Scanning protocol optimization and dose evaluation in coronary stenosis using multi-slices computed tomography

    Huang, Yung-hui; Chen, Chia-lin; Sheu, Chin-yin; Lee, Jason J. S.


    Cardiovascular diseases are the most common incidence for premature death in developed countries. A major fraction is attributable to atherosclerotic coronary artery disease, which may result in sudden cardiac failure. A reduction of mortality caused by myocardial infarction may be achieved if coronary atherosclerosis can be detected and treated at an early stage before symptoms occur. Therefore, there is need for an effective tool that allows identification of patients at increased risk for future cardiac events. The current multi-detector CT has been widely used for detection and quantification of coronary calcifications as a sign of coronary atherosclerosis. The aim of this study is to optimize the diagnostic values and radiation exposure in coronary artery calcium-screening examination using multi-slice CT (MSCT) with different image scan protocols. The radiation exposure for all protocols is evaluated by using computed tomography dose index (CTDI) phantom measurements. We chose an optimal scanning protocol and evaluated patient radiation dose in the MSCT coronary artery screenings and preserved its expecting diagnostic accuracy. These changes make the MSCT have more operation flexibility and provide more diagnostic values in current practice.

  7. Biological computation

    Lamm, Ehud


    Introduction and Biological BackgroundBiological ComputationThe Influence of Biology on Mathematics-Historical ExamplesBiological IntroductionModels and Simulations Cellular Automata Biological BackgroundThe Game of Life General Definition of Cellular Automata One-Dimensional AutomataExamples of Cellular AutomataComparison with a Continuous Mathematical Model Computational UniversalitySelf-Replication Pseudo Code Evolutionary ComputationEvolutionary Biology and Evolutionary ComputationGenetic AlgorithmsExample ApplicationsAnalysis of the Behavior of Genetic AlgorithmsLamarckian Evolution Genet

  8. Computer Software.

    Kay, Alan


    Discusses the nature and development of computer software. Programing, programing languages, types of software (including dynamic spreadsheets), and software of the future are among the topics considered. (JN)

  9. Cloud Computing

    Mirashe, Shivaji P


    Computing as you know it is about to change, your applications and documents are going to move from the desktop into the cloud. I'm talking about cloud computing, where applications and files are hosted on a "cloud" consisting of thousands of computers and servers, all linked together and accessible via the Internet. With cloud computing, everything you do is now web based instead of being desktop based. You can access all your programs and documents from any computer that's connected to the Internet. How will cloud computing change the way you work? For one thing, you're no longer tied to a single computer. You can take your work anywhere because it's always accessible via the web. In addition, cloud computing facilitates group collaboration, as all group members can access the same programs and documents from wherever they happen to be located. Cloud computing might sound far-fetched, but chances are you're already using some cloud applications. If you're using a web-based email program, such as Gmail or Ho...

  10. 64-row multi-dector computed tomography coronary image from a center with early experience: first illustration of learning curve

    Sze Piaw CHIN; Tiong Kiam ONG; Wei Ling CHAN; Chee Khoon LIEW; M.Tobias Seyfarth; Fong Yean Yip ALAN; Houng Bang LIEW; Kui Hian SIM


    Background and objectives The recent joint ACCF/AHA clinical competence statement on cardiac imaging with multi-detector computed tomography recommended a minimum of 6 months training and 300 contrast examinations, of which the candidate must be directly involved in at least 100 studies. Whether this is adequate to become proficient in interpretation of coronary computed tomogsignificant coronary stenosis in a center with 1 year's experience using a 64-row scanner. Methods A total of 778 patients underwent contrast-enhanced CTA between January and December 2005. Out of these patients, 301 patients also underwent contrast-enhanced conventional coronary angiography (CCA). These patients were divided into 4 groups according to the time the examination was underwent. Group Q1: first quarter of the year (n=20), Group Q2: second quarter (n=128), Group Q3: third quarter (n=134), and Group Results The sensitivity, specificity, positive, and negative predictive values were Q1 - 64%, 89%, 49% and 94%, respectively; Q2 -79%, 96%, 74% and 97%, respectively; Q3 - 78%, 96%, 74%, 97%, respectively, and Q4 - 100% for all. Conclusions In a center with formal training and high caseload, our accuracy in CTA analysis reached a plateau after 6 months experience. Test-bolus protocols produce better image quality and can improve accuracy. New centers embarking on CTA will need to overcome an initial 6-month learning curve depending upon the caseload during which time they should consider correlation with CCA.

  11. Computational Sustainability

    Eaton, Eric; University of Pennsylvania; Gomes, Carla P.; Cornell University; Williams, Brian; Massachusetts Institute of Technology


    Computational sustainability problems, which exist in dynamic environments with high amounts of uncertainty, provide a variety of unique challenges to artificial intelligence research and the opportunity for significant impact upon our collective future. This editorial provides an overview of artificial intelligence for computational sustainability, and introduces this special issue of AI Magazine.

  12. Grid Computing

    Foster, Ian


    The term "Grid Computing" refers to the use, for computational purposes, of emerging distributed Grid infrastructures: that is, network and middleware services designed to provide on-demand and high-performance access to all important computational resources within an organization or community. Grid computing promises to enable both evolutionary and revolutionary changes in the practice of computational science and engineering based on new application modalities such as high-speed distributed analysis of large datasets, collaborative engineering and visualization, desktop access to computation via "science portals," rapid parameter studies and Monte Carlo simulations that use all available resources within an organization, and online analysis of data from scientific instruments. In this article, I examine the status of Grid computing circa 2000, briefly reviewing some relevant history, outlining major current Grid research and development activities, and pointing out likely directions for future work. I also present a number of case studies, selected to illustrate the potential of Grid computing in various areas of science.

  13. Computational Science

    K. Li


    @@ Computer science is the discipline that anchors the computer industry which has been improving processor performance, communication bandwidth and storage capacity on the so called "Moore's law" curve or at the rate of doubling every 18 to 24 months during the past decades.




    Full Text Available Since the first idea of using GPU to general purpose computing, things have evolved over the years and now there are several approaches to GPU programming. GPU computing practically began with the introduction of CUDA (Compute Unified Device Architecture by NVIDIA and Stream by AMD. These are APIs designed by the GPU vendors to be used together with the hardware that they provide. A new emerging standard, OpenCL (Open Computing Language tries to unify different GPU general computing API implementations and provides a framework for writing programs executed across heterogeneous platforms consisting of both CPUs and GPUs. OpenCL provides parallel computing using task-based and data-based parallelism. In this paper we will focus on the CUDA parallel computing architecture and programming model introduced by NVIDIA. We will present the benefits of the CUDA programming model. We will also compare the two main approaches, CUDA and AMD APP (STREAM and the new framwork, OpenCL that tries to unify the GPGPU computing models.

  15. Platform computing


    "Platform Computing releases first grid-enabled workload management solution for IBM eServer Intel and UNIX high performance computing clusters. This Out-of-the-box solution maximizes the performance and capability of applications on IBM HPC clusters" (1/2 page) .

  16. Granular Computing


    The basic ideas and principles of granular computing (GrC) have been studied explicitly or implicitly in many fields in isolation. With the recent renewed and fast growing interest, it is time to extract the commonality from a diversity of fields and to study systematically and formally the domain independent principles of granular computing in a unified model. A framework of granular computing can be established by applying its own principles. We examine such a framework from two perspectives,granular computing as structured thinking and structured problem solving. From the philosophical perspective or the conceptual level,granular computing focuses on structured thinking based on multiple levels of granularity. The implementation of such a philosophy in the application level deals with structured problem solving.

  17. Computational Streetscapes

    Paul M. Torrens


    Full Text Available Streetscapes have presented a long-standing interest in many fields. Recently, there has been a resurgence of attention on streetscape issues, catalyzed in large part by computing. Because of computing, there is more understanding, vistas, data, and analysis of and on streetscape phenomena than ever before. This diversity of lenses trained on streetscapes permits us to address long-standing questions, such as how people use information while mobile, how interactions with people and things occur on streets, how we might safeguard crowds, how we can design services to assist pedestrians, and how we could better support special populations as they traverse cities. Amid each of these avenues of inquiry, computing is facilitating new ways of posing these questions, particularly by expanding the scope of what-if exploration that is possible. With assistance from computing, consideration of streetscapes now reaches across scales, from the neurological interactions that form among place cells in the brain up to informatics that afford real-time views of activity over whole urban spaces. For some streetscape phenomena, computing allows us to build realistic but synthetic facsimiles in computation, which can function as artificial laboratories for testing ideas. In this paper, I review the domain science for studying streetscapes from vantages in physics, urban studies, animation and the visual arts, psychology, biology, and behavioral geography. I also review the computational developments shaping streetscape science, with particular emphasis on modeling and simulation as informed by data acquisition and generation, data models, path-planning heuristics, artificial intelligence for navigation and way-finding, timing, synthetic vision, steering routines, kinematics, and geometrical treatment of collision detection and avoidance. I also discuss the implications that the advances in computing streetscapes might have on emerging developments in cyber

  18. From macro-scale to micro-scale computational anatomy: a perspective on the next 20 years.

    Mori, Kensaku


    This paper gives our perspective on the next two decades of computational anatomy, which has made great strides in the recognition and understanding of human anatomy from conventional clinical images. The results from this field are now used in a variety of medical applications, including quantitative analysis of organ shapes, interventional assistance, surgical navigation, and population analysis. Several anatomical models have also been used in computational anatomy, and these mainly target millimeter-scale shapes. For example, liver-shape models are almost completely modeled at the millimeter scale, and shape variations are described at such scales. Most clinical 3D scanning devices have had just under 1 or 0.5 mm per voxel resolution for over 25 years, and this resolution has not changed drastically in that time. Although Z-axis (head-to-tail direction) resolution has been drastically improved by the introduction of multi-detector CT scanning devices, in-plane resolutions have not changed very much either. When we look at human anatomy, we can see different anatomical structures at different scales. For example, pulmonary blood vessels and lung lobes can be observed in millimeter-scale images. If we take 10-µm-scale images of a lung specimen, the alveoli and bronchiole regions can be located in them. Most work in millimeter-scale computational anatomy has been done by the medical-image analysis community. In the next two decades, we encourage our community to focus on micro-scale computational anatomy. In this perspective paper, we briefly review the achievements of computational anatomy and its impacts on clinical applications; furthermore, we show several possibilities from the viewpoint of microscopic computational anatomy by discussing experimental results from our recent research activities.

  19. Chromatin computation.

    Barbara Bryant

    Full Text Available In living cells, DNA is packaged along with protein and RNA into chromatin. Chemical modifications to nucleotides and histone proteins are added, removed and recognized by multi-functional molecular complexes. Here I define a new computational model, in which chromatin modifications are information units that can be written onto a one-dimensional string of nucleosomes, analogous to the symbols written onto cells of a Turing machine tape, and chromatin-modifying complexes are modeled as read-write rules that operate on a finite set of adjacent nucleosomes. I illustrate the use of this "chromatin computer" to solve an instance of the Hamiltonian path problem. I prove that chromatin computers are computationally universal--and therefore more powerful than the logic circuits often used to model transcription factor control of gene expression. Features of biological chromatin provide a rich instruction set for efficient computation of nontrivial algorithms in biological time scales. Modeling chromatin as a computer shifts how we think about chromatin function, suggests new approaches to medical intervention, and lays the groundwork for the engineering of a new class of biological computing machines.

  20. Computing methods

    Berezin, I S


    Computing Methods, Volume 2 is a five-chapter text that presents the numerical methods of solving sets of several mathematical equations. This volume includes computation sets of linear algebraic equations, high degree equations and transcendental equations, numerical methods of finding eigenvalues, and approximate methods of solving ordinary differential equations, partial differential equations and integral equations.The book is intended as a text-book for students in mechanical mathematical and physics-mathematical faculties specializing in computer mathematics and persons interested in the

  1. Cloud Computing

    Baun, Christian; Nimis, Jens; Tai, Stefan


    Cloud computing is a buzz-word in today's information technology (IT) that nobody can escape. But what is really behind it? There are many interpretations of this term, but no standardized or even uniform definition. Instead, as a result of the multi-faceted viewpoints and the diverse interests expressed by the various stakeholders, cloud computing is perceived as a rather fuzzy concept. With this book, the authors deliver an overview of cloud computing architecture, services, and applications. Their aim is to bring readers up to date on this technology and thus to provide a common basis for d

  2. Computer interfacing

    Dixey, Graham


    This book explains how computers interact with the world around them and therefore how to make them a useful tool. Topics covered include descriptions of all the components that make up a computer, principles of data exchange, interaction with peripherals, serial communication, input devices, recording methods, computer-controlled motors, and printers.In an informative and straightforward manner, Graham Dixey describes how to turn what might seem an incomprehensible 'black box' PC into a powerful and enjoyable tool that can help you in all areas of your work and leisure. With plenty of handy

  3. Computational physics

    Newman, Mark


    A complete introduction to the field of computational physics, with examples and exercises in the Python programming language. Computers play a central role in virtually every major physics discovery today, from astrophysics and particle physics to biophysics and condensed matter. This book explains the fundamentals of computational physics and describes in simple terms the techniques that every physicist should know, such as finite difference methods, numerical quadrature, and the fast Fourier transform. The book offers a complete introduction to the topic at the undergraduate level, and is also suitable for the advanced student or researcher who wants to learn the foundational elements of this important field.

  4. Computational Literacy

    Chongtay, Rocio; Robering, Klaus


    In recent years, there has been a growing interest in and recognition of the importance of Computational Literacy, a skill generally considered to be necessary for success in the 21st century. While much research has concentrated on requirements, tools, and teaching methodologies for the acquisit......In recent years, there has been a growing interest in and recognition of the importance of Computational Literacy, a skill generally considered to be necessary for success in the 21st century. While much research has concentrated on requirements, tools, and teaching methodologies...... for the acquisition of Computational Literacy at basic educational levels, focus on higher levels of education has been much less prominent. The present paper considers the case of courses for higher education programs within the Humanities. A model is proposed which conceives of Computational Literacy as a layered...

  5. Computing Religion

    Nielbo, Kristoffer Laigaard; Braxton, Donald M.; Upal, Afzal


    The computational approach has become an invaluable tool in many fields that are directly relevant to research in religious phenomena. Yet the use of computational tools is almost absent in the study of religion. Given that religion is a cluster of interrelated phenomena and that research...... concerning these phenomena should strive for multilevel analysis, this article argues that the computational approach offers new methodological and theoretical opportunities to the study of religion. We argue that the computational approach offers 1.) an intermediary step between any theoretical construct...... and its targeted empirical space and 2.) a new kind of data which allows the researcher to observe abstract constructs, estimate likely outcomes, and optimize empirical designs. Because sophisticated mulitilevel research is a collaborative project we also seek to introduce to scholars of religion some...


    Andrzej Augustynek


    Full Text Available In June 2006, over 12.6 million Polish users of the Web registered. On the average, each of them spent 21 hours and 37 minutes monthly browsing the Web. That is why the problems of the psychological aspects of computer utilization have become an urgent research subject. The results of research into the development of Polish information society carried out in AGH University of Science and Technology, under the leadership of Leslaw H. Haber, in the period from 2000 until present time, indicate the emergence dynamic changes in the ways of computer utilization and their circumstances. One of the interesting regularities has been the inverse proportional relation between the level of computer skills and the frequency of the Web utilization.It has been found that in 2005, compared to 2000, the following changes occurred:- A significant drop in the number of students who never used computers and the Web;- Remarkable increase in computer knowledge and skills (particularly pronounced in the case of first years student- Decreasing gap in computer skills between students of the first and the third year; between male and female students;- Declining popularity of computer games.It has been demonstrated also that the hazard of computer screen addiction was the highest in he case of unemployed youth outside school system. As much as 12% of this group of young people were addicted to computer. A lot of leisure time that these youths enjoyed inducted them to excessive utilization of the Web. Polish housewives are another population group in risk of addiction to the Web. The duration of long Web charts carried out by younger and younger youths has been another matter of concern. Since the phenomenon of computer addiction is relatively new, no specific therapy methods has been developed. In general, the applied therapy in relation to computer addition syndrome is similar to the techniques applied in the cases of alcohol or gambling addiction. Individual and group

  7. Thermoluminescent dosimetry in computed tomography

    Lara C, A.; Rivera M, T. [IPN, Centro de Investigacion en Ciencia Aplicada y Tecnologia Avanzada, Unidad Legaria, Av. Legaria 694, Col. Irrigacion, 11500 Ciudad de Mexico (Mexico); Osorio V, M. [ISSSTE, Centro Medico Nacional 20 de Noviembre, Felix Cuevas 540, Col. del Valle, 03100 Ciudad de Mexico (Mexico); Hernandez O, O., E-mail: [Hospital General de Mexico, Dr. Balmis 148, Col. Doctores, 06726 Ciudad de Mexico (Mexico)


    In this work we studied the dosimetry performed on CT scan in two different equipment, SOMATOM and Phillips, with 16 and 64 slice respectively. We used 51 pellets of lithium fluoride doped with magnesium and titanium (LiF: Mg, Ti) also knows as TLD-100 due to its physical properties and its easy of use, in this study, first analysis a batch of 56 pellets, but only 53 pellets were optimal for this study, cesium-137 was used as source irradiation, then proceeded to calibrate the batch with X-rays source, measuring the corresponding dose in a Farmers ionization chamber, then, we obtained a calibration curve, and we used as reference to calculation of the applied dose, finally designing ergonomic mesh, were it was deposited a TLD 100, placed in a regions of interest were made to each scan type. Once characterized our material proceeded to testing in 30 patients, which were irradiated with X-ray tube, whose operation was performed at 80, 120 kV with a current of 100, 300 and 400 m A according to scanning protocol. Overall we measured dose of 5 mGy to 53 mGy, these measurements reflect significant dose to can induced cancer, due previous reports published, that doses greater than 20 mGy there is a risk of developing cancer in the long term, but in practice when it assigned a medical diagnosis, there are no dose limits due to benefits patients, however, IAEA publish recommendations that allow us to carry out optimum handling of ionizing radiation, among these is the quality control of the tomography equipment that helps greatly reduce patient dose. (Author)

  8. Computational sustainability

    Kersting, Kristian; Morik, Katharina


    The book at hand gives an overview of the state of the art research in Computational Sustainability as well as case studies of different application scenarios. This covers topics such as renewable energy supply, energy storage and e-mobility, efficiency in data centers and networks, sustainable food and water supply, sustainable health, industrial production and quality, etc. The book describes computational methods and possible application scenarios.

  9. Quantum Computers


    efficient or less costly than their classical counterparts. A large-scale quantum computer is certainly an extremely ambi- tious goal, appearing to us...outperform the largest classical supercomputers in solving some specific problems important for data encryption. In the long term, another application...which the quantum computer depends, causing the quantum mechanically destructive process known as decoherence . Decoherence comes in several forms

  10. Computational chemistry

    Arnold, J. O.


    With the advent of supercomputers, modern computational chemistry algorithms and codes, a powerful tool was created to help fill NASA's continuing need for information on the properties of matter in hostile or unusual environments. Computational resources provided under the National Aerodynamics Simulator (NAS) program were a cornerstone for recent advancements in this field. Properties of gases, materials, and their interactions can be determined from solutions of the governing equations. In the case of gases, for example, radiative transition probabilites per particle, bond-dissociation energies, and rates of simple chemical reactions can be determined computationally as reliably as from experiment. The data are proving to be quite valuable in providing inputs to real-gas flow simulation codes used to compute aerothermodynamic loads on NASA's aeroassist orbital transfer vehicles and a host of problems related to the National Aerospace Plane Program. Although more approximate, similar solutions can be obtained for ensembles of atoms simulating small particles of materials with and without the presence of gases. Computational chemistry has application in studying catalysis, properties of polymers, all of interest to various NASA missions, including those previously mentioned. In addition to discussing these applications of computational chemistry within NASA, the governing equations and the need for supercomputers for their solution is outlined.

  11. CT冠状动脉成像对男性吸烟冠心病患者斑块量化特征的评价%Value of quantification of coronary artery disease in male smokers using cardiac computed tomographic angiography

    庞殿申; 迟华群; 张秀英; 王飞飞


    Objective:To explore the difference of quantification of coronary artery plaques between smokers and nonsmokers using cardiac computed tomographic angiography (CCTA). Methods:A total of 354 patients including 121 smokers and 233 controls who underwent 64-slice CCTA and confirmed to have coronary plaques were studied. Plaque area,plaque volume,plaque burden,remodeling and ratio of thickness and length were compared between the two groups. Results:There was no difference for age,diabetes mellitus rate,BMI,blood pressure and blood lipid between the two groups. Smokers group had higher plaque area(median:7.03 mm2 vs. 5.81 mm2),plaque volume(28.31 mm3 vs. 13.67 mm3),plaque burden(49.52% vs. 35.34%),remodel-ing index(1.29 vs. 1.08) and ratio of thickness and length(0.35 vs. 0.25). Conclusion:Plaque area,plaque volume,plaque bur-den,remodeling and ratio of thickness and length measured on 64-slice CCTA are higher in smokers than those in nonsmokers.%目的:探讨吸烟者和非吸烟者64排CT冠状动脉成像(coronary CT angiography,CCTA)斑块量化特征的区别。方法:拟诊冠心病行64排CCTA检查且证实有斑块者354例,比较吸烟组121例和非吸烟组233例的冠状动脉粥样硬化斑块的最大横截面积、体积、斑块负荷、重构指数和厚度长度比。结果:2组年龄、体质量指数、糖尿病、高血压、高血脂发病率差异均无统计学意义(均P>0.05)。吸烟组斑块的最大横截面积、体积、斑块负荷、重构指数、厚度长度比分别为(7.03±3.51)mm2、(28.31±14.03)mm3、(49.52±16.07)%、1.29±0.36、0.35±0.13,均显著高于非吸烟组的(5.81±2.43)mm2、(13.67±5.00)mm3、(35.34±10.12)%、1.08±0.27、0.25±0.15(均P<0.05)。结论:64排CT能够有效测量斑块,吸烟患者的斑块体积、面积及斑块负荷、重构指数、厚度长度比均显著大于非吸烟患者。

  12. Computational creativity

    López de Mántaras Badia, Ramon


    Full Text Available New technologies, and in particular artificial intelligence, are drastically changing the nature of creative processes. Computers are playing very significant roles in creative activities such as music, architecture, fine arts, and science. Indeed, the computer is already a canvas, a brush, a musical instrument, and so on. However, we believe that we must aim at more ambitious relations between computers and creativity. Rather than just seeing the computer as a tool to help human creators, we could see it as a creative entity in its own right. This view has triggered a new subfield of Artificial Intelligence called Computational Creativity. This article addresses the question of the possibility of achieving computational creativity through some examples of computer programs capable of replicating some aspects of creative behavior in the fields of music and science.Las nuevas tecnologías y en particular la Inteligencia Artificial están cambiando de forma importante la naturaleza del proceso creativo. Los ordenadores están jugando un papel muy significativo en actividades artísticas tales como la música, la arquitectura, las bellas artes y la ciencia. Efectivamente, el ordenador ya es el lienzo, el pincel, el instrumento musical, etc. Sin embargo creemos que debemos aspirar a relaciones más ambiciosas entre los ordenadores y la creatividad. En lugar de verlos solamente como herramientas de ayuda a la creación, los ordenadores podrían ser considerados agentes creativos. Este punto de vista ha dado lugar a un nuevo subcampo de la Inteligencia Artificial denominado Creatividad Computacional. En este artículo abordamos la cuestión de la posibilidad de alcanzar dicha creatividad computacional mediante algunos ejemplos de programas de ordenador capaces de replicar algunos aspectos relacionados con el comportamiento creativo en los ámbitos de la música y la ciencia.

  13. Quantum computers.

    Ladd, T D; Jelezko, F; Laflamme, R; Nakamura, Y; Monroe, C; O'Brien, J L


    Over the past several decades, quantum information science has emerged to seek answers to the question: can we gain some advantage by storing, transmitting and processing information encoded in systems that exhibit unique quantum properties? Today it is understood that the answer is yes, and many research groups around the world are working towards the highly ambitious technological goal of building a quantum computer, which would dramatically improve computational power for particular tasks. A number of physical systems, spanning much of modern physics, are being developed for quantum computation. However, it remains unclear which technology, if any, will ultimately prove successful. Here we describe the latest developments for each of the leading approaches and explain the major challenges for the future.

  14. Cloud Computing

    Krogh, Simon


    The second half of the 20th century has been characterized by an explosive development in information technology (Maney, Hamm, & O'Brien, 2011). Processing power, storage capacity and network bandwidth have increased exponentially, resulting in new possibilities and shifting IT paradigms. In step...... with technological changes, the paradigmatic pendulum has swung between increased centralization on one side and a focus on distributed computing that pushes IT power out to end users on the other. With the introduction of outsourcing and cloud computing, centralization in large data centers is again dominating...... the IT scene. In line with the views presented by Nicolas Carr in 2003 (Carr, 2003), it is a popular assumption that cloud computing will be the next utility (like water, electricity and gas) (Buyya, Yeo, Venugopal, Broberg, & Brandic, 2009). However, this assumption disregards the fact that most IT production...

  15. Computational mechanics

    Raboin, P J


    The Computational Mechanics thrust area is a vital and growing facet of the Mechanical Engineering Department at Lawrence Livermore National Laboratory (LLNL). This work supports the development of computational analysis tools in the areas of structural mechanics and heat transfer. Over 75 analysts depend on thrust area-supported software running on a variety of computing platforms to meet the demands of LLNL programs. Interactions with the Department of Defense (DOD) High Performance Computing and Modernization Program and the Defense Special Weapons Agency are of special importance as they support our ParaDyn project in its development of new parallel capabilities for DYNA3D. Working with DOD customers has been invaluable to driving this technology in directions mutually beneficial to the Department of Energy. Other projects associated with the Computational Mechanics thrust area include work with the Partnership for a New Generation Vehicle (PNGV) for ''Springback Predictability'' and with the Federal Aviation Administration (FAA) for the ''Development of Methodologies for Evaluating Containment and Mitigation of Uncontained Engine Debris.'' In this report for FY-97, there are five articles detailing three code development activities and two projects that synthesized new code capabilities with new analytic research in damage/failure and biomechanics. The article this year are: (1) Energy- and Momentum-Conserving Rigid-Body Contact for NIKE3D and DYNA3D; (2) Computational Modeling of Prosthetics: A New Approach to Implant Design; (3) Characterization of Laser-Induced Mechanical Failure Damage of Optical Components; (4) Parallel Algorithm Research for Solid Mechanics Applications Using Finite Element Analysis; and (5) An Accurate One-Step Elasto-Plasticity Algorithm for Shell Elements in DYNA3D.

  16. Computational engineering


    The book presents state-of-the-art works in computational engineering. Focus is on mathematical modeling, numerical simulation, experimental validation and visualization in engineering sciences. In particular, the following topics are presented: constitutive models and their implementation into finite element codes, numerical models in nonlinear elasto-dynamics including seismic excitations, multiphase models in structural engineering and multiscale models of materials systems, sensitivity and reliability analysis of engineering structures, the application of scientific computing in urban water management and hydraulic engineering, and the application of genetic algorithms for the registration of laser scanner point clouds.

  17. Computer busses

    Buchanan, William


    As more and more equipment is interface or'bus' driven, either by the use of controllers or directly from PCs, the question of which bus to use is becoming increasingly important both in industry and in the office. 'Computer Busses' has been designed to help choose the best type of bus for the particular application.There are several books which cover individual busses, but none which provide a complete guide to computer busses. The author provides a basic theory of busses and draws examples and applications from real bus case studies. Busses are analysed using from a top-down approach, helpin

  18. Reconfigurable Computing

    Cardoso, Joao MP


    As the complexity of modern embedded systems increases, it becomes less practical to design monolithic processing platforms. As a result, reconfigurable computing is being adopted widely for more flexible design. Reconfigurable Computers offer the spatial parallelism and fine-grained customizability of application-specific circuits with the postfabrication programmability of software. To make the most of this unique combination of performance and flexibility, designers need to be aware of both hardware and software issues. FPGA users must think not only about the gates needed to perform a comp


    Evgeniy K. Khenner


    Abstract. The aim of the research is to draw attention of the educational community to the phenomenon of computational thinking which actively discussed in the last decade in the foreign scientific and educational literature, to substantiate of its importance, practical utility and the right on affirmation in Russian education.Methods. The research is based on the analysis of foreign studies of the phenomenon of computational thinking and the ways of its formation in the process of education;...

  20. Computer immunology.

    Forrest, Stephanie; Beauchemin, Catherine


    This review describes a body of work on computational immune systems that behave analogously to the natural immune system. These artificial immune systems (AIS) simulate the behavior of the natural immune system and in some cases have been used to solve practical engineering problems such as computer security. AIS have several strengths that can complement wet lab immunology. It is easier to conduct simulation experiments and to vary experimental conditions, for example, to rule out hypotheses; it is easier to isolate a single mechanism to test hypotheses about how it functions; agent-based models of the immune system can integrate data from several different experiments into a single in silico experimental system.

  1. Distributed computing

    Van Renesse, R


    This series will start with an introduction to distributed computing systems. Distributed computing paradigms will be presented followed by a discussion on how several important contemporary distributed operating systems use these paradigms. Topics will include processing paradigms, storage paradigms, scalability and robustness. Throughout the course everything will be illustrated by modern distributed systems notably the Amoeba distributed operating system of the Free University in Amsterdam and the Plan 9 operating system of AT&T Bell Laboratories. Plan 9 is partly designed and implemented by Ken Thompson, the main person behind the successful UNIX operating system.

  2. Computational Artifacts

    Schmidt, Kjeld; Bansler, Jørgen P.


    The key concern of CSCW research is that of understanding computing technologies in the social context of their use, that is, as integral features of our practices and our lives, and to think of their design and implementation under that perspective. However, the question of the nature of that wh...... of that which is actually integrated in our practices is often discussed in confusing ways, if at all. The article aims to try to clarify the issue and in doing so revisits and reconsiders the notion of ‘computational artifact’....

  3. Computer viruses

    Denning, Peter J.


    The worm, Trojan horse, bacterium, and virus are destructive programs that attack information stored in a computer's memory. Virus programs, which propagate by incorporating copies of themselves into other programs, are a growing menace in the late-1980s world of unprotected, networked workstations and personal computers. Limited immunity is offered by memory protection hardware, digitally authenticated object programs,and antibody programs that kill specific viruses. Additional immunity can be gained from the practice of digital hygiene, primarily the refusal to use software from untrusted sources. Full immunity requires attention in a social dimension, the accountability of programmers.

  4. Computer systems

    Olsen, Lola


    In addition to the discussions, Ocean Climate Data Workshop hosts gave participants an opportunity to hear about, see, and test for themselves some of the latest computer tools now available for those studying climate change and the oceans. Six speakers described computer systems and their functions. The introductory talks were followed by demonstrations to small groups of participants and some opportunities for participants to get hands-on experience. After this familiarization period, attendees were invited to return during the course of the Workshop and have one-on-one discussions and further hands-on experience with these systems. Brief summaries or abstracts of introductory presentations are addressed.

  5. Cloud Computing

    Antonopoulos, Nick


    Cloud computing has recently emerged as a subject of substantial industrial and academic interest, though its meaning and scope is hotly debated. For some researchers, clouds are a natural evolution towards the full commercialisation of grid systems, while others dismiss the term as a mere re-branding of existing pay-per-use technologies. From either perspective, 'cloud' is now the label of choice for accountable pay-per-use access to third party applications and computational resources on a massive scale. Clouds support patterns of less predictable resource use for applications and services a

  6. Computer security

    Gollmann, Dieter


    A completely up-to-date resource on computer security Assuming no previous experience in the field of computer security, this must-have book walks you through the many essential aspects of this vast topic, from the newest advances in software and technology to the most recent information on Web applications security. This new edition includes sections on Windows NT, CORBA, and Java and discusses cross-site scripting and JavaScript hacking as well as SQL injection. Serving as a helpful introduction, this self-study guide is a wonderful starting point for examining the variety of competing sec

  7. Riemannian computing in computer vision

    Srivastava, Anuj


    This book presents a comprehensive treatise on Riemannian geometric computations and related statistical inferences in several computer vision problems. This edited volume includes chapter contributions from leading figures in the field of computer vision who are applying Riemannian geometric approaches in problems such as face recognition, activity recognition, object detection, biomedical image analysis, and structure-from-motion. Some of the mathematical entities that necessitate a geometric analysis include rotation matrices (e.g. in modeling camera motion), stick figures (e.g. for activity recognition), subspace comparisons (e.g. in face recognition), symmetric positive-definite matrices (e.g. in diffusion tensor imaging), and function-spaces (e.g. in studying shapes of closed contours).   ·         Illustrates Riemannian computing theory on applications in computer vision, machine learning, and robotics ·         Emphasis on algorithmic advances that will allow re-application in other...

  8. Investigation of the role of computed tomography as an adjunct to autopsy in the evaluation of stillbirth.


    INTRODUCTION: The number of parents agreeing to autopsy following stillbirth is declining, which has undermined clinicians\\' ability to assess causes of intrauterine death and can impact counselling regarding recurrence. Post-mortem radiological imaging is a potential alternative method of investigating perinatal loss. The aim of this study was to assess the role of multi-detector computed tomography (MDCT) in the investigation of stillbirth. STUDY DESIGN: Following ethical approval and written consent, parents were offered MDCT of the stillborn infant. MDCT was performed with 3D reconstruction, and images were analysed for image quality, anthropomorphic measurements and pathologic findings. Body part and organ-specific measurements were performed; including head, chest and abdominal circumferences, and muscle and liver mass was also measured. Findings were correlated with obstetric history, post-mortem skeletal survey (plain radiography), and formal autopsy. RESULTS: Fourteen third-trimester stillborn infants were scanned. Image quality was moderate to excellent for most body structures. CT was better than plain radiography for imaging skeletal structures and large solid organs and demonstrated a range of pathologies including renal vein thrombosis, mesenteric calcification and skeletal hyperostosis that were not seen on plain radiographs. MDCT did not overlook autopsy findings and provided some additional information. CONCLUSION: This study confirms the feasibility of MDCT in the investigation of third trimester stillbirth. MDCT image quality is acceptable and the examination can demonstrate a range of anatomic and pathologic findings. Initially, its value may be as an important adjunct to conventional autopsy.

  9. Computational trigonometry

    Gustafson, K. [Univ. of Colorado, Boulder, CO (United States)


    By means of the author`s earlier theory of antieigenvalues and antieigenvectors, a new computational approach to iterative methods is presented. This enables an explicit trigonometric understanding of iterative convergence and provides new insights into the sharpness of error bounds. Direct applications to Gradient descent, Conjugate gradient, GCR(k), Orthomin, CGN, GMRES, CGS, and other matrix iterative schemes will be given.

  10. Computational Logistics

    This book constitutes the refereed proceedings of the 4th International Conference on Computational Logistics, ICCL 2013, held in Copenhagen, Denmark, in September 2013. The 19 papers presented in this volume were carefully reviewed and selected for inclusion in the book. They are organized...... in topical sections named: maritime shipping, road transport, vehicle routing problems, aviation applications, and logistics and supply chain management....

  11. Computational Logistics

    Pacino, Dario; Voss, Stefan; Jensen, Rune Møller


    This book constitutes the refereed proceedings of the 4th International Conference on Computational Logistics, ICCL 2013, held in Copenhagen, Denmark, in September 2013. The 19 papers presented in this volume were carefully reviewed and selected for inclusion in the book. They are organized...... in topical sections named: maritime shipping, road transport, vehicle routing problems, aviation applications, and logistics and supply chain management....

  12. Computational Finance

    Rasmussen, Lykke

    One of the major challenges in todays post-crisis finance environment is calculating the sensitivities of complex products for hedging and risk management. Historically, these derivatives have been determined using bump-and-revalue, but due to the increasing magnitude of these computations does...

  13. Computational biology

    Hartmann, Lars Røeboe; Jones, Neil; Simonsen, Jakob Grue


    Computation via biological devices has been the subject of close scrutiny since von Neumann’s early work some 60 years ago. In spite of the many relevant works in this field, the notion of programming biological devices seems to be, at best, ill-defined. While many devices are claimed or proved t...

  14. Computational Logistics

    Jensen, Rune Møller; Pacino, Dario; Voß, Stefan


    This book constitutes the refereed proceedings of the 4th International Conference on Computational Logistics, ICCL 2013, held in Copenhagen, Denmark, in September 2013. The 19 papers presented in this volume were carefully reviewed and selected for inclusion in the book. They are organized...

  15. Computing News

    McCubbin, N


    We are still five years from the first LHC data, so we have plenty of time to get the computing into shape, don't we? Well, yes and no: there is time, but there's an awful lot to do! The recently-completed CERN Review of LHC Computing gives the flavour of the LHC computing challenge. The hardware scale for each of the LHC experiments is millions of 'SpecInt95' (SI95) units of cpu power and tens of PetaBytes of data storage. PCs today are about 20-30SI95, and expected to be about 100 SI95 by 2005, so it's a lot of PCs. This hardware will be distributed across several 'Regional Centres' of various sizes, connected by high-speed networks. How to realise this in an orderly and timely fashion is now being discussed in earnest by CERN, Funding Agencies, and the LHC experiments. Mixed in with this is, of course, the GRID concept...but that's a topic for another day! Of course hardware, networks and the GRID constitute just one part of the computing. Most of the ATLAS effort is spent on software development. What we ...

  16. [Grid computing

    Wolinsky, H


    "Turn on a water spigot, and it's like tapping a bottomless barrel of water. Ditto for electricity: Flip the switch, and the supply is endless. But computing is another matter. Even with the Internet revolution enabling us to connect in new ways, we are still limited to self-contained systems running locally stored software, limited by corporate, institutional and geographic boundaries" (1 page).

  17. Radiological Protection in Cone Beam Computed Tomography (CBCT). ICRP Publication 129.

    Rehani, M M; Gupta, R; Bartling, S; Sharp, G C; Pauwels, R; Berris, T; Boone, J M


    The objective of this publication is to provide guidance on radiological protection in the new technology of cone beam computed tomography (CBCT). Publications 87 and 102 dealt with patient dose management in computed tomography (CT) and multi-detector CT. The new applications of CBCT and the associated radiological protection issues are substantially different from those of conventional CT. The perception that CBCT involves lower doses was only true in initial applications. CBCT is now used widely by specialists who have little or no training in radiological protection. This publication provides recommendations on radiation dose management directed at different stakeholders, and covers principles of radiological protection, training, and quality assurance aspects. Advice on appropriate use of CBCT needs to be made widely available. Advice on optimisation of protection when using CBCT equipment needs to be strengthened, particularly with respect to the use of newer features of the equipment. Manufacturers should standardise radiation dose displays on CBCT equipment to assist users in optimisation of protection and comparisons of performance. Additional challenges to radiological protection are introduced when CBCT-capable equipment is used for both fluoroscopy and tomography during the same procedure. Standardised methods need to be established for tracking and reporting of patient radiation doses from these procedures. The recommendations provided in this publication may evolve in the future as CBCT equipment and applications evolve. As with previous ICRP publications, the Commission hopes that imaging professionals, medical physicists, and manufacturers will use the guidelines and recommendations provided in this publication for implementation of the Commission's principle of optimisation of protection of patients and medical workers, with the objective of keeping exposures as low as reasonably achievable, taking into account economic and societal factors, and

  18. Computable Frames in Computable Banach Spaces

    S.K. Kaushik


    Full Text Available We develop some parts of the frame theory in Banach spaces from the point of view of Computable Analysis. We define computable M-basis and use it to construct a computable Banach space of scalar valued sequences. Computable Xd frames and computable Banach frames are also defined and computable versions of sufficient conditions for their existence are obtained.

  19. Assessment of radiation exposure on a dual-source computed tomography-scanner performing coronary computed tomography-angiography

    Kirchhoff, S., E-mail: sonja.kirchhoff@med.uni-muenchen.d [Institute of Clinical Radiology, University Hospital Munich - Grosshadern, Ludwig Maximilians-Universitaet Muenchen, Klinikum Grosshadern, Marchioninistrasse 15, 81377 Munich (Germany); Herzog, P., E-mail: peter.herzog@med.uni-muenchen.d [Institute of Clinical Radiology, University Hospital Munich - Grosshadern, Ludwig Maximilians-Universitaet Muenchen, Klinikum Grosshadern, Marchioninistrasse 15, 81377 Munich (Germany); Johnson, T., E-mail: Thorsten.johnson@med.uni-muenchen.d [Institute of Clinical Radiology, University Hospital Munich - Grosshadern, Ludwig Maximilians-Universitaet Muenchen, Klinikum Grosshadern, Marchioninistrasse 15, 81377 Munich (Germany); Boehm, H., E-mail: holger.boehm@med.uni-muenchen.d [Institute of Clinical Radiology, University Hospital Munich - Grosshadern, Ludwig Maximilians-Universitaet Muenchen, Klinikum Grosshadern, Marchioninistrasse 15, 81377 Munich (Germany); Nikolaou, K., E-mail: konstantin.nikolaou@med.uni-muenchen.d [Institute of Clinical Radiology, University Hospital Munich - Grosshadern, Ludwig Maximilians-Universitaet Muenchen, Klinikum Grosshadern, Marchioninistrasse 15, 81377 Munich (Germany); Reiser, M.F., E-mail: maximilian.reiser@med.uni-muenchen.d [Institute of Clinical Radiology, University Hospital Munich - Grosshadern, Ludwig Maximilians-Universitaet Muenchen, Klinikum Grosshadern, Marchioninistrasse 15, 81377 Munich (Germany); Becker, C.H., E-mail: christoph.becker@med.uni-muenchen.d [Institute of Clinical Radiology, University Hospital Munich - Grosshadern, Ludwig Maximilians-Universitaet Muenchen, Klinikum Grosshadern, Marchioninistrasse 15, 81377 Munich (Germany)


    Objective: The radiation exposure of a dual-source-64-channel multi-detector-computed-tomography-scanner (Somatom-Defintion, Siemens, Germany) was assessed in a phantom-study performing coronary-CT-angiography (CTCA) in comparison to patients' data randomly selected from routine scanning. Methods: 240 CT-acquisitions of a computed tomography dose index (CTDI)-phantom (PTW, Freiburg, Germany) were performed using a synthetically generated Electrocardiography (ECG)-signal with variable heart rates (30-180 beats per minute (bpm)). 120 measurements were acquired using continuous tube-output; 120 measurements were performed using ECG-synchronized tube-modulation. The pulsing window was set at minimum duration at 65% of the cardiac cycle between 30 and 75 bpm. From 90-180 bpm the pulsing window was set at 30-70% of the cardiac cycle. Automated pitch adaptation was always used. A comparison between phantom CTDI and two patient groups' CTDI corresponding to the two pulsing groups was performed. Results: Without ECG-tube-modulation CDTI-values were affected by heart-rate-changes resulting in 85.7 mGray (mGy) at 30 and 45 bpm, 65.5 mGy/60 bpm, 54.7 mGy/75 bpm, 46.5 mGy/90 bpm, 34.2 mGy/120 bpm, 27.0 mGy/150 bpm and 22.1 mGy/180 bpm equal to effective doses between 14.5 mSievert (mSv) at 30/45 bpm and 3.6 mSv at 180 bpm. Using ECG-tube-modulation these CTDI-values resulted: 32.6 mGy/30 bpm, 36.6 mGy/45 bpm, 31.4 mGy/60 bpm, 26.8 mGy/75 bpm, 23.7 mGy/90 bpm, 19.4 mGy/120 bpm, 17.2 mGy/150 bpm and 15.6 mGy/180 bpm equal to effective doses between 5.5 mSv at 30 bpm and 2.6 mSv at 180 bpm. Significant CTDI-differences were found between patients with lower/moderate and higher heart rates in comparison to the phantom CTDI-results. Conclusions: Dual source CTCA is particularly dose efficient at high heart rates when automated pitch adaptation, especially in combination with ECG-based tube-modulation is used. However in clinical routine scanning for patients with higher

  20. Computational Combustion

    Westbrook, C K; Mizobuchi, Y; Poinsot, T J; Smith, P J; Warnatz, J


    Progress in the field of computational combustion over the past 50 years is reviewed. Particular attention is given to those classes of models that are common to most system modeling efforts, including fluid dynamics, chemical kinetics, liquid sprays, and turbulent flame models. The developments in combustion modeling are placed into the time-dependent context of the accompanying exponential growth in computer capabilities and Moore's Law. Superimposed on this steady growth, the occasional sudden advances in modeling capabilities are identified and their impacts are discussed. Integration of submodels into system models for spark ignition, diesel and homogeneous charge, compression ignition engines, surface and catalytic combustion, pulse combustion, and detonations are described. Finally, the current state of combustion modeling is illustrated by descriptions of a very large jet lifted 3D turbulent hydrogen flame with direct numerical simulation and 3D large eddy simulations of practical gas burner combustion devices.

  1. Computational Electromagnetics

    Rylander, Thomas; Bondeson, Anders


    Computational Electromagnetics is a young and growing discipline, expanding as a result of the steadily increasing demand for software for the design and analysis of electrical devices. This book introduces three of the most popular numerical methods for simulating electromagnetic fields: the finite difference method, the finite element method and the method of moments. In particular it focuses on how these methods are used to obtain valid approximations to the solutions of Maxwell's equations, using, for example, "staggered grids" and "edge elements." The main goal of the book is to make the reader aware of different sources of errors in numerical computations, and also to provide the tools for assessing the accuracy of numerical methods and their solutions. To reach this goal, convergence analysis, extrapolation, von Neumann stability analysis, and dispersion analysis are introduced and used frequently throughout the book. Another major goal of the book is to provide students with enough practical understan...

  2. Computational Physics

    Thijssen, Jos


    1. Introduction; 2. Quantum scattering with a spherically symmetric potential; 3. The variational method for the Schrödinger equation; 4. The Hartree-Fock method; 5. Density functional theory; 6. Solving the Schrödinger equation in periodic solids; 7. Classical equilibrium statistical mechanics; 8. Molecular dynamics simulations; 9. Quantum molecular dynamics; 10. The Monte Carlo method; 11. Transfer matrix and diagonalisation of spin chains; 12. Quantum Monte Carlo methods; 13. The infinite element method for partial differential equations; 14. The lattice Boltzmann method for fluid dynamics; 15. Computational methods for lattice field theories; 16. High performance computing and parallelism; Appendix A. Numerical methods; Appendix B. Random number generators; References; Index.

  3. Everything Computes

    Bill; Hofmann


    Dear American Professor, I am a student in Beijing. At the beginning of last semester, we fourroommates gathered some 10,000 yuan (a big sum here. approximately 1150USD ) and bought a computer, which is our joint-property. Since the computercame into our room, it was used round the clock except the time we were havingc1asses. So even at midnight, when I woke up from the dream, I could still see

  4. Computer Game


    Using NASA studies of advanced lunar exploration and colonization, KDT Industries, Inc. and Wesson International have developed MOONBASE, a computer game. The player, or team commander, must build and operate a lunar base using NASA technology. He has 10 years to explore the surface, select a site and assemble structures brought from Earth into an efficient base. The game was introduced in 1991 by Texas Space Grant Consortium.

  5. Computational Electromagnetics


    a collaboration between Caltech’s postdoctoral associate N. Albin and OB) have shown that, for a variety of reasons, the first-order...KZK approximation", Nathan Albin , Oscar P. Bruno, Theresa Y. Cheung and Robin O. Cleveland, preprint, (2011) "A Spectral FC Solver for the Compressible...Navier-Stokes Equations in General Domains I: Explicit time-stepping" Nathan Albin and Oscar P. Bruno, To appear in Journal of Computational Physics

  6. Computer vision

    Gennery, D.; Cunningham, R.; Saund, E.; High, J.; Ruoff, C.


    The field of computer vision is surveyed and assessed, key research issues are identified, and possibilities for a future vision system are discussed. The problems of descriptions of two and three dimensional worlds are discussed. The representation of such features as texture, edges, curves, and corners are detailed. Recognition methods are described in which cross correlation coefficients are maximized or numerical values for a set of features are measured. Object tracking is discussed in terms of the robust matching algorithms that must be devised. Stereo vision, camera control and calibration, and the hardware and systems architecture are discussed.

  7. Customizable computing

    Chen, Yu-Ting; Gill, Michael; Reinman, Glenn; Xiao, Bingjun


    Since the end of Dennard scaling in the early 2000s, improving the energy efficiency of computation has been the main concern of the research community and industry. The large energy efficiency gap between general-purpose processors and application-specific integrated circuits (ASICs) motivates the exploration of customizable architectures, where one can adapt the architecture to the workload. In this Synthesis lecture, we present an overview and introduction of the recent developments on energy-efficient customizable architectures, including customizable cores and accelerators, on-chip memory

  8. Computational crystallization.

    Altan, Irem; Charbonneau, Patrick; Snell, Edward H


    Crystallization is a key step in macromolecular structure determination by crystallography. While a robust theoretical treatment of the process is available, due to the complexity of the system, the experimental process is still largely one of trial and error. In this article, efforts in the field are discussed together with a theoretical underpinning using a solubility phase diagram. Prior knowledge has been used to develop tools that computationally predict the crystallization outcome and define mutational approaches that enhance the likelihood of crystallization. For the most part these tools are based on binary outcomes (crystal or no crystal), and the full information contained in an assembly of crystallization screening experiments is lost. The potential of this additional information is illustrated by examples where new biological knowledge can be obtained and where a target can be sub-categorized to predict which class of reagents provides the crystallization driving force. Computational analysis of crystallization requires complete and correctly formatted data. While massive crystallization screening efforts are under way, the data available from many of these studies are sparse. The potential for this data and the steps needed to realize this potential are discussed.

  9. Tensor computations in computer algebra systems

    Korolkova, A V; Sevastyanov, L A


    This paper considers three types of tensor computations. On their basis, we attempt to formulate criteria that must be satisfied by a computer algebra system dealing with tensors. We briefly overview the current state of tensor computations in different computer algebra systems. The tensor computations are illustrated with appropriate examples implemented in specific systems: Cadabra and Maxima.

  10. Brain computer

    Sarah N. Abdulkader


    Full Text Available Brain computer interface technology represents a highly growing field of research with application systems. Its contributions in medical fields range from prevention to neuronal rehabilitation for serious injuries. Mind reading and remote communication have their unique fingerprint in numerous fields such as educational, self-regulation, production, marketing, security as well as games and entertainment. It creates a mutual understanding between users and the surrounding systems. This paper shows the application areas that could benefit from brain waves in facilitating or achieving their goals. We also discuss major usability and technical challenges that face brain signals utilization in various components of BCI system. Different solutions that aim to limit and decrease their effects have also been reviewed.

  11. Multiparty Computations

    Dziembowski, Stefan

    papers [1,2]. In [1] we assume that the adversary can corrupt any set from a given adversary structure. In this setting we study a problem of doing efficient VSS and MPC given an access to a secret sharing scheme (SS). For all adversary structures where VSS is possible at all, we show that, up...... an impossibility result indicating that a similar equivalence does not hold for Multiparty Computation (MPC): we show that even if protocols are given black-box access for free to an idealized secret sharing scheme secure for the access structure in question, it is not possible to handle all relevant access...... adversary structure. We propose new VSS and MPC protocols that are substantially more efficient than the ones previously known. Another contribution of [2] is an attack against a Weak Secret Sharing Protocol (WSS) of [3]. The attack exploits the fact that the adversary is adaptive. We present this attack...

  12. Social Computing

    CERN. Geneva


    The past decade has witnessed a momentous transformation in the way people interact with each other. Content is now co-produced, shared, classified, and rated by millions of people, while attention has become the ephemeral and valuable resource that everyone seeks to acquire. This talk will describe how social attention determines the production and consumption of content within both the scientific community and social media, how its dynamics can be used to predict the future and the role that social media plays in setting the public agenda. About the speaker Bernardo Huberman is a Senior HP Fellow and Director of the Social Computing Lab at Hewlett Packard Laboratories. He received his Ph.D. in Physics from the University of Pennsylvania, and is currently a Consulting Professor in the Department of Applied Physics at Stanford University. He originally worked in condensed matter physics, ranging from superionic conductors to two-dimensional superfluids, and made contributions to the theory of critical p...

  13. Computer Tree

    Onur AĞAOĞLU


    Full Text Available It is crucial that gifted and talented students should be supported by different educational methods for their interests and skills. The science and arts centres (gifted centres provide the Supportive Education Program for these students with an interdisciplinary perspective. In line with the program, an ICT lesson entitled “Computer Tree” serves for identifying learner readiness levels, and defining the basic conceptual framework. A language teacher also contributes to the process, since it caters for the creative function of the basic linguistic skills. The teaching technique is applied for 9-11 aged student level. The lesson introduces an evaluation process including basic information, skills, and interests of the target group. Furthermore, it includes an observation process by way of peer assessment. The lesson is considered to be a good sample of planning for any subject, for the unpredicted convergence of visual and technical abilities with linguistic abilities.

  14. computer networks

    N. U. Ahmed


    Full Text Available In this paper, we construct a new dynamic model for the Token Bucket (TB algorithm used in computer networks and use systems approach for its analysis. This model is then augmented by adding a dynamic model for a multiplexor at an access node where the TB exercises a policing function. In the model, traffic policing, multiplexing and network utilization are formally defined. Based on the model, we study such issues as (quality of service QoS, traffic sizing and network dimensioning. Also we propose an algorithm using feedback control to improve QoS and network utilization. Applying MPEG video traces as the input traffic to the model, we verify the usefulness and effectiveness of our model.

  15. Computational micromechanics

    Ortiz, M.


    Selected issues in computational micromechanics are reviewed, with particular emphasis on multiple-scale problems and micromechanical models of material behavior. Examples considered include: the bridging of atomistic and continuum scales, with application to nanoindentation and the brittle-to-ductile transition; the development of dislocation-based constitutive relations for pure metallic crystals and intermetallic compounds, with applications to fracture of single crystals and bicrystals; the simulation of non-planar three-dimensional crack growth at the microscale, with application to mixed mode I III effective behavior and crack trapping and bridging in fiber-reinforced composites; and the direct micromechanical simulation of fragmentation of brittle solids and subsequent flow of the comminuted phase.

  16. Quantitative assessment of early experimental diabetes in rats using dynamic contrast-enhanced computed tomography

    Murase, Kenya [Department of Medical Physics and Engineering, Division of Medical Technology and Science, Faculty of Health Science, Graduate School of Medicine, Osaka University, 1-7 Yamadaoka, Suita, Osaka 565-0871 (Japan)], E-mail:; Kitamura, Akihiro; Tachibana, Atsushi; Kusakabe, Yoshinori; Matsuura, Risa; Miyazaki, Shohei [Department of Medical Physics and Engineering, Division of Medical Technology and Science, Faculty of Health Science, Graduate School of Medicine, Osaka University, 1-7 Yamadaoka, Suita, Osaka 565-0871 (Japan)


    Purpose: To quantitatively assess the time course of changes of the renal volume and function in the early phase of streptozotocin (STZ)-induced diabetes in rats using dynamic contrast-enhanced computed tomography (DCE-CT). Methods: The DCE-CT studies were performed in 24 male Sprague-Dawley rats (n = 6 for control and n = 18 for STZ-treated group) on days 0, 4, 7, 11, and 14 using a multi-detector row CT. The rats of an STZ-treated group were given intraperitoneally 65 mg/kg body weight of STZ on day 0, and were divided into two groups based on the blood glucose concentration on day 4 being less than 300 mg/dL [STZ-treated group (L), n = 8] or greater than 300 mg/dL [STZ-treated group (G), n = 10]. The contrast clearance per unit renal volume (K{sub 1}) was estimated from the DCE-CT data using the Patlak model. The renal volume (V{sub CT}) was calculated by manually delineating the kidney on the contrast-enhanced CT image. The contrast clearance of the entire kidney (K) was obtained by K{sub 1} x V{sub CT}. Results: V{sub CT} in the STZ-treated group was significantly enlarged on day 4 compared to that on day 0 and continued until day 14. Although there were no significant changes in the time course of K{sub 1} in all groups, K in the STZ-treated groups (L) and (G) significantly increased on days 7 and 4, respectively, and continued until day 14, suggesting that hyperfiltration occurs in parallel with renal volume enlargement. Conclusion: The present method appears useful for quantitatively evaluating the time course of STZ-induced diabetes in rats, because it allows repeated and simultaneous evaluation of renal morphology and function.

  17. The role of multidetector computed tomography in evaluation of small bowel obstructions

    Mehmet Fatih İnci


    Full Text Available Objective: The purpose of the study was to evaluate therole and additional diagnostic contribution of multi-detectorcomputed tomography (MDCT in patients with acuteabdominal pain caused by small bowel obstruction.Materials and methods: A total of 48 patients who admittedto our hospital with acute abdominal pain and underwentMDCT on suspicion of intestinal obstruction and hadabdominal surgery between January 2012 and October2012 were included to our study. MDCT images were interpretedby two experienced radiologist retrospectively.All clinical data and surgery notes also were evaluated.Patients had surgery due to penetrating or blunt abdominalinjury were excluded.Results: Of these 48 patients, 26 (54.1% were male and22 (45.9% were female. Patients’ ages ranged 25 to 71and mean age was 52±5.4 years. The causes of intestinalobstruction of patients were adhesions for 12 (46.1% patients,tumors for 7 (26.9% patients, external hernias for5 (19.2% patients, internal hernia for 1 (3.9% patient andintussusception for 1 (3.9% patient. A total concordancebetween the MDCT findings and definitive diagnosis wasfound in 26 of 23 cases and the sensitivity and specifityof MDCT in the diagnosis of small bowel obstruction werefound to be 88.5% and 90%, respectively.Conclusion: MDCT is a fast, effective and reliable imagingmethod for preoperative diagnosing small bowel obstructioncauses acute abdominal pain with the advantagesof MDCT such as multi-planar and three-dimensionalreformatted imaging.Key words: Acute abdominal pain, multi-detector computed tomography, small bowel obstruction

  18. Fibromuscular dysplasia in living renal donors: Still a challenge to computed tomographic angiography

    Blondin, D., E-mail: blondin@med.uni-duesseldorf.d [Institute of Radiology, University Hospital Duesseldorf, Moorenstr. 5, D-40225 Duesseldorf (Germany); Lanzman, R.; Schellhammer, F. [Institute of Radiology, University Hospital Duesseldorf, Moorenstr. 5, D-40225 Duesseldorf (Germany); Oels, M. [Department of Nephrology (Germany); Grotemeyer, D. [Department of Vascular Surgery and Renal Transplantation (Germany); Baldus, S.E. [Institute of Pathology (Germany); Rump, L.C. [Department of Nephrology (Germany); Sandmann, W. [Department of Vascular Surgery and Renal Transplantation (Germany); Voiculescu, A. [Department of Nephrology (Germany)


    Background: Computed tomographic angiography has become the standard evaluating method of potential living renal donors in most centers. Although incidence of fibromuscular dysplasia is low (3.5-6%), this pathology may be relevant for success of renal transplantation. The incidence of FMD in our population of LRD and reliability of CTA for detecting vascular pathology were the aims of this study. Materials and methods: 101 living renal donors, examined between 7/2004 and 9/2008 by CTA, were included in a retrospective evaluation. The examinations were carried out using a 64 Multi-detector CT (Siemens Medical Solutions, Erlangen). The presence or absence of the characteristic signs of fibromuscular dysplasia, as 'string-of-beads' appearance, focal stenosis or aneurysms, were assessed and graded from mild (=1) to severe (=3). Furthermore, vascular anatomy and arterial stenosis were investigated in this study. Retrospective analysis of CTA and ultrasound were compared with operative and histological reports. Results: Four cases of fibromuscular dysplasia (incidence 3.9%) in 101 renal donors were diagnosed by transplanting surgeons and histopathology, respectively. Three cases could be detected by CTA. In one donor even retrospective analysis of CTA was negative. Ten accessory arteries, 14 venous anomalies and 12 renal arteries stenosis due to atherosclerosis were diagnosed by CTA and could be confirmed by the operative report. Conclusion: CTA is sufficient for detection of hemodynamic relevant stenosis and vascular anatomy. Only one patient with a mild form of FMD was under estimated. Therefore, if the CTA shows slightest irregularities which are not typical for atherosclerotic lesions, further diagnostic work up by DSA might still be necessary.

  19. Quantitative image analysis for the detection of motion artefacts in coronary artery computed tomography

    Kristanto, Wisnumurti; van Ooijen, Peter M.; Dikkers, Riksta; Greuter, Marcel J.; Zijlstra, Felix; Oudkerk, Matthijs


    Multi detector-row CT (MDCT), the current preferred method for coronary artery disease assessment, is still affected by motion artefacts. To rule out motion artefacts, qualitative image analysis is usually performed. Our study aimed to develop a quantitative image analysis for motion artefacts detec

  20. High-resolution computed tomography in patients with atypical 'cardiac' chest pain: a study investigating patients at 10-year cardiovascular risks defined by the Framingham and PROCAM scores

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


    Background and objective Atypical 'cardiac' chest pain (ACCP) is not usually caused by myocardial ischaemia. Current noninvasive investigations for these symptoms are not yet as accurate as invasive coronary angiography. The latest 64-row multi-detector computed tomography (MDCT) technology is non-invasive, has high specificity and negative predictive values for the detection of significant coronary disease. Our aim was to investigate if this modality can provide more information in the assessment of outpatients with ACCP in addition to established cardiovascular risk scores. Methods Seventy consecutive patients presenting to the outpatient clinic with ACCP underwent 64-row MDCT scan of the coronary arteries. They were categorized into low, medium or high risk groups based upon the Framingham and PROCAM scores. We defined a clinically abnormal MDCT scan as coronary stenosis =50% or calcium score >400 Agatston. Results Fifty-three (75.7%) patients did not have clinically abnormal scans. Framingham score classified 43 patients as low-risk while PROCAM classified 59 patients as low-risk. MDCT scans were abnormal for 18.6% and 22.0% of the respective low-risk group of patients. For patients with medium-to-high risk, 33.3% and 36.4% of Framingham and PROCAM patient groups respectively had abnormal MDCT scans. Conclusion MDCT adds valuable information in the assessment of patients with ACCP by identifying a significant proportion of patients categorized as low-risk to have underlying significant coronary stenosis and coronary calcification by established cardiovascular risk scores.

  1. Gender disparities in the association between epicardial adipose tissue volume and coronary atherosclerosis: A 3-dimensional cardiac computed tomography imaging study in Japanese subjects

    Dagvasumberel Munkhbaatar


    Full Text Available Abstract Background Growing evidence suggests that epicardial adipose tissue (EAT may contribute to the development of coronary artery disease (CAD. In this study, we explored gender disparities in EAT volume (EATV and its impact on coronary atherosclerosis. Methods The study population consisted of 90 consecutive subjects (age: 63 ± 12 years; men: 47, women: 43 who underwent 256-slice multi-detector computed tomography (MDCT coronary angiography. EATV was measured as the sum of cross-sectional epicardial fat area on CT images, from the lower surface of the left pulmonary artery origin to the apex. Subjects were segregated into the CAD group (coronary luminal narrowing > 50% and non-CAD group. Results EATV/body surface area (BSA was higher among men in the CAD group than in the non-CAD group (62 ± 13 vs. 33 ± 10 cm3/m2, p 3/m2, not significant. Multivariate logistic analysis showed that EATV/BSA was the single predictor for >50% coronary luminal narrowing in men (p Conclusions Increased EATV is strongly associated with coronary atherosclerosis in men.

  2. Computed Tomography (CT) -- Sinuses

    ... News Physician Resources Professions Site Index A-Z Computed Tomography (CT) - Sinuses Computed tomography (CT) of the ... of CT of the Sinuses? What is CT (Computed Tomography) of the Sinuses? Computed tomography, more commonly ...

  3. Study of Quantum Computing

    Prashant Anil Patil


    Full Text Available This paper gives the detailed information about Quantum computer, and difference between quantum computer and traditional computers, the basis of Quantum computers which are slightly similar but still different from traditional computer. Many research groups are working towards the highly technological goal of building a quantum computer, which would dramatically improve computational power for particular tasks. Quantum computer is very much use full for computation purpose in field of Science and Research. Large amount of data and information will be computed, processing, storing, retrieving, transmitting and displaying information in less time with that much of accuracy which is not provided by traditional computers.

  4. Analog and hybrid computing

    Hyndman, D E


    Analog and Hybrid Computing focuses on the operations of analog and hybrid computers. The book first outlines the history of computing devices that influenced the creation of analog and digital computers. The types of problems to be solved on computers, computing systems, and digital computers are discussed. The text looks at the theory and operation of electronic analog computers, including linear and non-linear computing units and use of analog computers as operational amplifiers. The monograph examines the preparation of problems to be deciphered on computers. Flow diagrams, methods of ampl

  5. Computing handbook computer science and software engineering

    Gonzalez, Teofilo; Tucker, Allen


    Overview of Computer Science Structure and Organization of Computing Peter J. DenningComputational Thinking Valerie BarrAlgorithms and Complexity Data Structures Mark WeissBasic Techniques for Design and Analysis of Algorithms Edward ReingoldGraph and Network Algorithms Samir Khuller and Balaji RaghavachariComputational Geometry Marc van KreveldComplexity Theory Eric Allender, Michael Loui, and Kenneth ReganFormal Models and Computability Tao Jiang, Ming Li, and Bala


    Saumya Ranjan


    Full Text Available Computed tomography, CT scan of Paranasal Sinuses (PNS is the gold standard test in diagnosing sinonasal abnormalities, which has the advantage of being able to show fine anatomic detail in serial tomographic sections, eliminating the gross volume averaging inherent in plain films. AIM To have surveillance of sinonasal abnormalities, from computed tomography CT scan of PNS, in the hospital in one year. MATERIAL AND METHODS Symptomatic patients pertaining to nose and paranasal sinuses were subjected to non-contrast CT scan of PNS by a GE Multi-detector CT scan with 0.6mm slices, for the diagnoses of sinonasal abnormalities from CT scan findings. RESULTS Of 339 patients, the primary radiological diagnoses were 66 Deviated Nasal Septum (DNS, 54 maxillary sinusitis, 47 ethmoid sinusitis, 44 Inferior Turbinate Hypertrophy (ITH, 35 maxillary sinus-mucosal hypertrophy, 28 frontal sinusitis, 20 ethmoidal polyp, 14 antrochoanal polyp, 12 nasal mass, 9 nasopharyngeal mass, 5 concha bullosa, 3 pan-sinusitis and 2 sphenoid sinusitis. There were 190 male and 149 female patients, diagnosed to have cited sinonasal diseases. The age distribution of diseases was: 57 in ≤ 14 years (Paediatric, 155 in 15-39 years (Adults and 127 in the age group of ≥ 40 years (Elderly; 86 cases of sinusitis were associated with anatomical variants, among which deviated nasal septum and inferior turbinate hypertrophy were accountable for 31 cases each. CONCLUSION Deviated Nasal Septum (DNS was the most frequently encountered condition in 19.5% of the total 339 patients. Among the patients of DNS, ITH was the most frequent co-existent abnormality. Maxillary sinusitis was the commonest sinus infection. Deviated nasal septum and inferior turbinate hypertrophy were most common anatomical variants seen in cases of sinusitis. CT scan of PNS is an indispensable diagnostic tool, which assisted in planning and advocating appropriate treatment modalities for sinonasal abnormalities.

  7. 16-Detector row computed tomographic coronary angiography in patients undergoing evaluation for aortic valve replacement: comparison with catheter angiography

    Manghat, N.E.; Morgan-Hughes, G.J.; Broadley, A.J.; Undy, M.B.; Wright, D.; Marshall, A.J.; Roobottom, C.A


    Aim: To evaluate the diagnostic accuracy of 16-detector row computed tomography (CT) in assessing haemodynamically significant coronary artery stenoses in patients under evaluation for aortic stenosis pre-aortic valve replacement. Subjects and methods: Forty consecutive patients under evaluation for severe aortic stenosis and listed for cardiac catheterization before potential aortic valve replacement underwent coronary artery calcium (CAC) scoring and retrospective electrocardiogram (ECG)-gated multi-detector row computed tomographic coronary angiography (MDCTA) using a GE Lightspeed 16-detector row CT within 1 month of invasive coronary angiography (ICA) for comparative purposes. All 13 major coronary artery segments of the American Heart Association model were evaluated for the presence of {>=}50% stenosis and compared to the reference standard. Data were analysed on a segment-by-segment basis and also in 'whole patient' terms. Results: A total of 412/450 segments from 35 patients were suitable for analysis. The overall accuracy of MDCTA for detection of segments with {>=}50% stenosis was high, with a sensitivity of 81.3%, specificity 95.0%, positive predictive value (PPV) 57.8%, and negative predictive value (NPV) 98.4%. On a 'whole-patient' basis, 100% (19/19) of patients with significant coronary disease were correctly identified and there were no false-negatives. Excluding patients with CAC >1000 from the analysis improved the accuracy of MDCTA to: sensitivity 90%, specificity 98.1%, PPV 60%, NPV 99.7%. Conclusion: Non-invasive 16-detector row MDCTA accurately excludes significant coronary disease in patients with severe aortic stenosis undergoing evaluation before aortic valve replacement and in whom ICA can therefore be avoided. Its segment-by-segment accuracy is improved further if CAC > 1000 is used as a gatekeeper to MDCTA.

  8. Computing with functionals—computability theory or computer science?

    Normann, Dag


    We review some of the history of the computability theory of functionals of higher types, and we will demonstrate how contributions from logic and theoretical computer science have shaped this still active subject.