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Sample records for 64-slice computed tomography

  1. 64-slice Computed Tomography Assessment of Coronary Artery Stents: a Phantom Study

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    Mahnken, A.H.; Muehlenbruch, G.; Seyfarth, T.; Flohr, T.; Stanzel, S.; Wildberger, J.E.; Guenther, R.W.; Kuettner, A. [Aachen Univ. of Technology (Germany). Dept. of Diagnostic Radiology

    2006-02-15

    Purpose: To compare the use of a new 64-slice computed tomography (CT) scanner with 16-slice CT in the visualization of coronary artery stent lumen. Material and Methods: Eight different coronary artery stents, each with a diameter of 3 mm, were placed in a static chest phantom. The phantom was positioned in the CT gantry at an angle of 0 deg and 45 deg towards the z-axis and examined with both a 64-slice and a 16-slice CT scanner. Effective slice thickness was 0.6 mm with 64-slice CT and 1 mm with 16-slice CT. A reconstruction increment of 0.3 mm was applied in both scanners. Image quality was assessed visually using a 5-point grading scale. Stent diameters were measured and compared using paired Wilcoxon tests. Results: Artificial lumen reduction was significantly less with 64-slice than with 16-slice CT. Average visible stent lumen was 53.4% using 64-slice CT and 47.5% with 16-slice MSCT. Most severe artifacts were seen in stents with radiopaque markers. Using 64-slice CT, image noise increased by approximately 30% due to thinner slice thickness. Conclusion: Improved spatial resolution of 64-slice CT resulted in superior assessment of coronary artery stent lumen compared to 16-slice CT. However, a relevant part of the stent lumen is still not assessable with multi-slice CT.

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

    DEFF Research Database (Denmark)

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

    2012-01-01

    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 arter...

  3. Contrast-enhanced 64-slice computed tomography in detection and evaluation of anomalous coronary arteries

    International Nuclear Information System (INIS)

    Anomalous coronary artery (ACA) has either an unusual origin or different anatomical course and is associated with sudden cardiac death. The absence or nonspecific symptoms of ACA make its diagnosis difficult. Mostly, ACA is diagnosed coincidentally during invasive coronary angiogram (ICA). A conventional computed tomography (CT) cannot provide detailed images of coronary arteries of the moving heart, but 64-slice CT, with its short acquisition time, can provide detailed anatomy of coronary arteries non-invasively. In this study, we assessed the validity of contrast-enhanced 64-slice CT in the evaluation of ACA. ICA was performed in 7,574 patients for the diagnosis or evaluation of occlusive coronary artery disease and detected coronary anomalies in 56 patients (0.7%). We then performed 64-slice CT in 53 patients out of the 56 patients with demonstrated or suspected coronary anomaly, showing the origin and the course of the ACA along with stenosis, except for one patient who could not be evaluated due to image distortion artifacts. Contrast-enhanced 64-slice CT was also performed in 374 patients with vague signs and symptoms, detecting coronary anomalies in 7 patients (1.2%). Thus, in the total of 59 patients undergone 64-slice CT, we were able to visualize the entire abnormal coronary tree with a high diagnostic image quality. This is the first study to demonstrate the utility of 64-slice CT in a large series of ACA. Contrast-enhanced 64-slice CT is superior to ICA to identify the presence and course of ACA and should be the first line diagnostic tool in the evaluation of ACA. (author)

  4. Diagnostic Accuracy of 64-Slice Multislice Computed Tomography in Assessment of Coronary Artery Bypass Grafts

    Directory of Open Access Journals (Sweden)

    A. Arjmand Shabestari

    2007-05-01

    Full Text Available Background and Objective: Nowadays 64-slice mul-tislice computed tomography (MSCT has gained a wide acceptance as a non-invasive diagnostic imaging modality in native coronary arteries. This study was performed to determine the diagnostic accuracy of 64-slice MSCT in assessment of coronary artery by-pass grafting (CABG patency. Materials and Methods: 73 patients underwent both coronary CT-angiography (CTA using 64-slice MSCT scanner and quantitative coronary angiography (QCA were studied. Arterial and venous CABG patency was graded as: a-normal, b-patent with non-significant (<50% diameter reduction stenosis, c-patent with significant (≥50% diameter reduction stenosis or d-totally occluded. The results of CTA and QCA were compared. Results: Totally, 236 CABG were assessed, including 49 arterial and 187 venous grafts. Sensitivity, specific-ity, positive predictive value (PPV and negative pre-dictive value (NPV in detecting normal patency of arterial grafts were 100%, 85%, 95% and 100%, re-spectively and those in finding normal patency of ve-nous grafts all were 100%. The above-mentioned fig-ures for non-significant stenosis were 67% (2 out of 3 patients, 100%, 100% and 98% in arterial and 95%, 100%, 100% and 99% in venous grafts, respectively. Regarding to the significant stenosis, the results were 67% (2 out of 3 patients, 100%, 100% and 98% in arterial and 100%, 99%, 94% and 100% in venous grafts, respectively. All of these numerals were meas-ured being 100% for total occlusion of both arterial and venous grafts. Conclusion: Diagnostic accuracy of 64-slice MSCT in detecting normal patency, non-significant stenosis, significant stenosis and total occlusion of arterial and particularly venous CABG is extremely high so that QCA may be eventually substituted by CTA in a near future.

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

    Institute of Scientific and Technical Information of China (English)

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

    2009-01-01

    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.

  6. Evaluation of the Optimal Image Reconstruction Interval for Coronary Artery Imaging Using 64-Slice Computed Tomography

    International Nuclear Information System (INIS)

    Background: Cardiac computed tomography (CT) has become an established complement in cardiac imaging. Thus, optimized image quality is diagnostically crucial. Purpose: To prospectively evaluate whether, by using 64-slice CT, a specific reconstruction interval can be identified providing best image quality for all coronary artery segments and each individual coronary artery. Material and Methods: 311 coronary segments of 14 men and seven women were analyzed using 64-slice CT. Data reconstruction was performed in 5% increments from 5-100% of the R-R interval. Four experienced observers independently evaluated image quality of the coronary arteries according to the AHA classification. A three-point ranking scale was applied: 1, very poor, no evaluation possible; 2, diagnostically sufficient quality; 3, highest image quality, no artifacts. Results: The best reconstruction point for all segments was found to be 65% of the R-R interval (mean value 2.4±0.5; P<0.05). On a per-artery basis, best image quality was again achieved at 65% of the R-R interval: RCA 2.2±0.4, LCA 2.4±0.5, LM 2.5±0.2, LAD 2.3±0.4, LCX 2.3±0.5. Conclusion: By using 64-slice CT, the need for adjusting the reconstruction point to each coronary segment might be overcome. Best image quality was achieved with image reconstruction at 65% of the R-R interval for all coronary segments as well as each coronary artery

  7. Digital medical technology based on 64-slice computed tomography in hepatic surgery

    Institute of Scientific and Technical Information of China (English)

    FANG Chi-hua; HUANG Yan-peng; CHEN Mian-ling; LU Chao-min; LI Xiao-feng; QIU Wen-feng

    2010-01-01

    Background With the rapid development of computer technology, digital medicine has become a new direction in surgery. The application of digital medicine in hepatic surgery is still at the early stage and less reported in the literature. The aim of this study was to apply digital medical technology in the context of hepatic surgery. Methods Data from 64-slice helical computed tomography of 17 patients, including 13 with hepatocellular carcinoma and 4 with hepatic hemangioma, were imported into independently developed medical image software program, segmentation and three-dimensional reconstruction were performed. The three-dimensional models were then processed with the FreeForm Modeling System. We used virtual surgical instruments to perform surgery on the models. Simulated surgeries included six hepatic segmentectomies, four left hemihepatectomies, three right hemihepatectomies for hepatocellular carcinoma, one hepatic segmentectomy, two stripping surgeries, and one irregular segmentectomy combined with stripping surgery for hemangioma. For resections involving more than three hepatic segments, total and residual functional hepatic volumes were measured before and after simulation surgery, and the resection ratio was calculated.Results The anatomy of the models was distinct and was used to localize lesions. We used virtual surgical instruments to perform simulated surgeries and used the models to optimize actual surgeries. We were able to minimize resection volume as well as surgical risk.Conclusions Digital medical technology is helpful in the diagnosis of hepatic disease and in optimizing surgical plans. Three-dimensional models can decrease surgical risk and help prevent postoperative hepatic failure.

  8. Radiation dose reduction by using 100-kV tube voltage in cardiac 64-slice computed tomography: A comparative study

    International Nuclear Information System (INIS)

    Objective: To evaluate a 100-kilovoltage (kV) tube voltage protocol regarding radiation dose and image quality, in comparison with the standard 120 kV setting in cardiac computed tomography angiography (CCTA). Methods: 103 patients undergoing retrospective ECG-gated helical 64-slice CCTA were enrolled (100 kV group: 51 patients; 120 kV group: 52 patients). Inclusion criteria were: (1) BMI 2; (2) weight 25 kg/m2). Conclusions: The 100 kV protocol significantly reduces the radiation dose in CCTA in patients with a low BMI 2 and a low calcium load while maintaining high image quality and the advantages of helical scan algorithm.

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

    DEFF Research Database (Denmark)

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

    2008-01-01

    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 co...... complex interventional procedures. We present a case where CT angiography was performed just prior to the clinical presentation of acute stent thrombosis in a 55-year-old male who was treated with the crush technique in a bifurcation lesion Udgivelsesdato: 2008/7...

  10. 64 slice-coronary computed tomography sensitivity and specificity in the evaluation of coronary artery bypass graft stenosis: A meta-analysis.

    Science.gov (United States)

    Barbero, Umberto; Iannaccone, Mario; d'Ascenzo, Fabrizio; Barbero, Cristina; Mohamed, Abdirashid; Annone, Umberto; Benedetto, Sara; Celentani, Dario; Gagliardi, Marco; Moretti, Claudio; Gaita, Fiorenzo

    2016-08-01

    A non-invasive approach to define grafts patency and stenosis in the follow-up of coronary artery bypass graft (CABG) patients may be an interesting alternative to coronary angiography. 64-slice-coronary computed tomography is nowadays a diffused non-invasive method that permits an accurate evaluation of coronary stenosis, due to a high temporal and spatial resolution. However, its sensitivity and specificity in CABG evaluation has to be clearly defined, since published studies used different protocols and scanners. We collected all studies investigating patients with stable symptoms and previous CABG and reporting the comparison between diagnostic performances of invasive coronary angiography and 64-slice-coronary computed tomography. As a result, sensitivity and specificity of 64-slice-coronary computed tomography for CABG occlusion were 0.99 (95% CI 0.97-1.00) and 0.99 (95% CI: 0.99-1.00) with an area under the curve (AUC) of 0.99. 64-slice-coronary computed tomography sensitivity and specificity for the presence of any CABG stenosis >50% were 0.98 (95% CI: 0.97-0.99) and 0.98 (95% CI: 0.96-0.98), while AUC was 0.99. At meta-regression, neither the age nor the time from graft implantation had effect on sensitivity and specificity of 64-slice-coronary computed tomography detection of significant CABG stenosis or occlusion. In conclusion 64-slice-coronary computed tomography confirmed its high sensitivity and specificity in CABG stenosis or occlusion evaluation. PMID:27140337

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

    International Nuclear Information System (INIS)

    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 mm3, 90.4%) than in calcified plaque (median, 0.7 mm3, 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.

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

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

    2013-12-15

    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.

  13. High-resolution ex vivo imaging of coronary artery stents using 64-slice computed tomography - initial experience

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    Rist, Carsten; Nikolaou, Konstantin; Wintersperger, Bernd J.; Reiser, Maximilian F.; Becker, Christoph R. [Ludwig-Maximilians University, Department of Clinical Radiology, Munich (Germany); Flohr, Thomas [Siemens Medical Solutions, CT Division, Forchheim (Germany)

    2006-07-15

    The aim of the study was to evaluate the potential of new-generation multi-slice computed tomography (CT) scanner technology for the delineation of coronary artery stents in an ex vivo setting. Nine stents of various diameters (seven stents 3 mm, two stents 2.5 mm) were implanted into the coronary arteries of ex vivo porcine hearts and filled with a mixture of an iodine-containing contrast agent. Specimens were scanned with a 16-slice CT (16SCT) machine; (Somatom Sensation 16, Siemens Medical Solutions), slice thickness 0.75 mm, and a 64-slice CT (64SCT, Somatom Sensation 64), slice-thickness 0.6 mm. Stent diameters as well as contrast densities were measured, on both the 16SCT and 64SCT images. No significant differences of CT densities were observed between the 16SCT and 64SCT images outside the stent lumen: 265{+-}25HU and 254{+-}16HU (P=0.33), respectively. CT densities derived from the 64SCT images and 16SCT images within the stent lumen were 367{+-}36HU versus 402{+-}28HU, P<0.05, respectively. Inner and outer stent diameters as measured from 16SCT and 64SCT images were 2.68{+-}0.08 mm versus 2.81{+-}0.07 mm and 3.29{+-}0.06 mm versus 3.18{+-}0.07 mm (P<0.05), respectively. The new 64SCT scanner proved to be superior in the ex vivo assessment of coronary artery stents to the conventional 16SCT machine. Increased spatial resolution allows for improved assessment of the coronary artery stent lumen. (orig.)

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

    Science.gov (United States)

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

    2010-04-30

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

  15. Analysis of shielding calculation methods for 16- and 64-slice computed tomography facilities

    Energy Technology Data Exchange (ETDEWEB)

    Moreno, C; Cenizo, E; Bodineau, C; Mateo, B; Ortega, E M, E-mail: c_morenosaiz@yahoo.e [Servicio de RadiofIsica Hospitalaria, Hospital Regional Universitario Carlos Haya, Malaga (Spain)

    2010-09-15

    The new multislice computed tomography (CT) machines require some new methods of shielding calculation, which need to be analysed. NCRP Report No. 147 proposes three shielding calculation methods based on the following dosimetric parameters: weighted CT dose index for the peripheral axis (CTDI{sub w,per}), dose-length product (DLP) and isodose maps. A survey of these three methods has been carried out. For this analysis, we have used measured values of the dosimetric quantities involved and also those provided by the manufacturer, making a comparison between the results obtained. The barrier thicknesses when setting up two different multislice CT instruments, a Philips Brilliance 16 or a Philips Brilliance 64, in the same room, are also compared. Shielding calculation from isodose maps provides more reliable results than the other two methods, since it is the only method that takes the actual scattered radiation distribution into account. It is concluded therefore that the most suitable method for calculating the barrier thicknesses of the CT facility is the one based on isodose maps. This study also shows that for different multislice CT machines the barrier thicknesses do not necessarily become bigger as the number of slices increases, because of the great dependence on technique used in CT protocols for different anatomical regions.

  16. The influence of heart rate, slice thickness, and calcification density on calcium scores using 64-slice multidetector computed tomography - A systematic phantom study

    NARCIS (Netherlands)

    Groen, Jaap M.; Greuter, Marcel J.; Schmidt, Bernhard; Suess, Christoph; Vliegenthart, Rozemarijn; Oudkerk, Matthis

    2007-01-01

    Objective: The purpose of this study was to investigate the influence of heart rate, slice thickness, and calcification density on absolute value and variability of calcium score using 64-slice multidetector computed tomography (MDCT). Methods and Materials: Three artificial arteries containing each

  17. Diagnostic accuracy of 64-slice computed tomography coronary angiography for the detection of in-stent restenosis: A meta-analysis

    NARCIS (Netherlands)

    N. Carrabba (Nazario); J.D. Schuijf (Joanne); F.R. de Graaf (Fleur); G. Parodi (Guido); E. Maffei (Erica); R. Valenti (Renato); A. Palumbo (Alessandro); A.C. Weustink (Annick); N.R.A. Mollet (Nico); G. Accetta (Gabriele); F. Cademartiri (Filippo); D. Antoniucci (David); J.J. Bax (Jeroen)

    2010-01-01

    textabstractBackground: We sought to evaluate the diagnostic accuracy of 64-slice multi-detector row computed tomography (MDCT) compared with invasive coronary angiography for in-stent restenosis (ISR) detection. Methods: MEDLINE, Cochrane library, and BioMed Central database searches were performed

  18. Prognostic value of absence or presence of coronary artery disease determined by 64-slice computed tomography coronary angiography A systematic review and meta-analysis

    DEFF Research Database (Denmark)

    Abdulla, Jawdat; Asferg, Camilla Lundegaard; Kofoed, Klaus Fuglsang

    2011-01-01

    To determine via a meta-analysis the prognostic value of 64-slice computed tomography angiography (CTA) by quantifying risk of major adverse cardiac events (MACE) in different patient groups classified according to CT angiographic findings. A systematic literature search and meta-analyses was con...

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

    Directory of Open Access Journals (Sweden)

    Farzad Esmaeili

    2013-01-01

    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.

  20. Assessment of right ventricular function for patients with rheumatic mitral stenosis by 64-slice multi-detector row computed tomography: comparison with magnetic resonance imaging

    Institute of Scientific and Technical Information of China (English)

    ZHANG Xiao-chun; YANG Zhi-gang; GUO Yin-kun; ZHANG Rui-ming; WANG Jian; ZHOU Dai-quan; CHENG Lin; CHEN Lin

    2012-01-01

    Background Right ventricular (RV) dysfunction ensues due to rheumatic mitral stenosis (RMS).The evaluation of RV function is clinically important for the diagnosis,treatment,and follow-up for patients with different degrees of RMS.Thepurpose of this study was to determine whether the 64-slice multi-detector row computed tomography (64-slice MDCT)can assess the RV function in RMS with high accuracy and reproducibility when compared to MR imaging (MRI).Methods Right ventricular end-diastolic and end-systolic volumes (RV-EDV and RV-ESV),stroke volume (RV-SV),ejection fraction (RV-EF),cardiac output (RV-CO),and wall mass (RV-Mass) were measured with dedicated cardiac analysis software on 64-slice MDCT and compared with values measured with MRI in 43 consecutive patients with RMS.Agreement between MRI and 64-MDCT results were compared with Bland and Altman analysis and linear regression analysis.Repeated measurements were performed to determine intraobserver and interobserver variability.Results No significant differences were revealed in calculated RV function parameters between the two methods.RV-EDV,RV-ESV,RV-SV,RV-EF,RV-CO,and RV-Mass by 64-slice MDCT were similar to those by MRI (P>0.05).There were good correlations (r=0.98,0.97,0.96,0.96,0.95 and 0.77,respectively) and close agreement (bias=-0.2 ml,-1.0ml,0.8 ml,0.5%,26.1 ml,and 0.5 g,respectively,P>0.05).The variability in 64-slice MDCT measurements was similar to that in MRI values.Conclusion ECG-gated 64-slice MDCT could assess the RV function in RMS with high accuracy and reproducibility when compared to MRI.

  1. The role of 64-slice multi-detector computed tomography in the detection of subclinical atherosclerosis of the coronary artery.

    Science.gov (United States)

    Jeong, Hae Chang; Ahn, Youngkeun; Ko, Jum Suk; Lee, Min Goo; Sim, Doo Sun; Park, Keun Ho; Yoon, Nam Sik; Youn, Hyun Ju; Hong, Young Joon; Kim, Kye Hun; Park, Hyung Wook; Kim, Ju Han; Kim, Yun-Hyeon; Jeong, Myung Ho; Cho, Jeong Gwan; Park, Jong Chun; Kang, Jung Chaee

    2010-12-01

    Multi-detector computed tomography (MDCT) has been used for detecting or excluding coronary atherosclerotic stenosis in symptomatic patients. However, the role of MDCT for routine medical examination in asymptomatic, high-risk patients has not been established. We therefore conducted the present study to test the hypothesis that MDCT could be a valuable method for detecting subclinical coronary artery stenosis in asymptomatic patients. An observational, retrospective, single-centre study was conducted with a cohort of 1,529 patients (mean age, 56.4 ± 8.3 years; 1,353 males) who had undergone MDCT as part of their general medical checkups from November 2005 to April 2008. The patients who had a past history of coronary artery disease, typical chest pain, or evidence of myocardial ischemia were excluded. During clinical follow up of these patients, the incidence of subclinical coronary stenosis and the usefulness of MDCT for routine medical examination in asymptomatic patients were investigated. Of the 1,529 enrolled patients, 42.3% had hypertension, 13.5% had diabetes mellitus, 7.7% had hyperlipidemia, and 40.4% were current smokers. Abnormal MDCT findings were noted in 560 (36.6%) patients, who were classified into two groups. One group had the presence coronary calcium with a luminal diameter stenosis of the coronary artery of bridge, and 23 patients (1.5%) presented with significant stenosis. The patients with significant stenosis underwent percutaneous coronary intervention (PCI) with stent implantation. Major adverse cardiac events occurred in only 2 patients who had been treated with PCI during a mean follow-up period of 387 ± 253 days. The incidence of significant subclinical coronary stenosis as detected by MDCT in a general medical check-up was 3.4%, and the false-positive rate of MDCT for detecting significant coronary artery stenosis was 55.8% (29/52). 64-Slice MDCT can be a useful tool for noninvasive evaluation of coronary arteries in

  2. 64-slice spiral computed tomography of the coronary arteries: dose reduction using an optimized imaging protocol including individual weight-adaptation of voltage and current-time product

    International Nuclear Information System (INIS)

    Radiation dose and image quality were compared between a standard protocol (40 patients, group A) and a weight-adapted protocol of voltage and current-time product (44 patients, group B) using 64-slice coronary multidetector computed tomography (MDCT). Effective dose estimate was lower by 37% in all patients of group B (9.2±2.5 mSv) compared with group A (14.6±2.3 mSv, P<0.0001). Group B patients with a small body mass index (BMI) benefited most with a dose reduction of 53% (6.7±1.5 mSv in group B versus 14.1±1.8 mSv in group A, P < 0.0001). Moderate reductions of 32% and 20% were achieved for patients with a medium and large BMI, respectively. Reduction in radiation dose did not affect the image quality as assessed by image noise, signal-to-noise ratios, and number of coronary segments with good diagnostic image quality. Individual weight-adaptation of voltage and current-time product significantly reduces the radiation dose without loss of image quality. (orig.)

  3. 64层锥束CT扫描的优化系统%Optimization of System Design for 64-slice Cone Beam Computed Tomography

    Institute of Scientific and Technical Information of China (English)

    谢强; Eugene Williams; Charlie Shaughnessy; 唐向阳

    2005-01-01

    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.

  4. 肋软骨骨折的64层螺旋CT诊断价值分析%Diagnostic value analysis of 64-slice spiral computed tomography in Costal Cartilage Fractures

    Institute of Scientific and Technical Information of China (English)

    周超; 李凤英; 汪云超

    2012-01-01

    Objective To discuss the value of 64-slice spiral CT in diagnosing costal cartilage fracture so as to improve the level of imaging diagnosis. Method Three-dimensional images of 64-slice computed tomography in 28 patients with fracture in costal cartilage were analyzed,and compared with chest plain film and axial CT images. Results In 28 patients, 33 costal cartilage fractures were found with three-dimensional images of 64-slice computed tomography; 23 patients with X-ray, 9 patients with axial CT images did not show costal cartilage fracture.Conclusion Three-dimensional images of 64-slice computed tomography were better than plain film and CT axial scans in costal cartilage fracture, it may be considered as the best imaging method in detecting the costal cartilage fracture.%目的 探讨64层螺旋CT在肋软骨骨折诊断中的价值,提高诊断水平.方法 回顾性分析28例肋软骨骨折患者的64层螺旋CT三维重组图像,并与X线平片CT直接扫描横断位图像对照.结果 28例患者中64层螺旋CT三维重组图像发现肋软骨骨折33处,23例X线平片、9例CT直接横断位图像未显示.结论 64层螺旋CT对肋软骨骨折的显示优于普通X线平片及常规CT胸部横断位图像,可望成为检测肋软骨骨折的最佳影像学检查手段.

  5. Comparing culprit lesions in ST-segment elevation and non-ST-segment elevation acute coronary syndrome with 64-slice multidetector computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Huang, W.-C. [School of Medicine, National Yang-Ming University, Taipei, Taiwan (China); Cardiovascular Medical Center, Kaohsiung Veterans General Hospital, No. 386, Dar-Chung First Road, Kaohsiung, Taiwan (China)], E-mail: w.c.huang@yahoo.com.tw; Liu, C.-P. [School of Medicine, National Yang-Ming University, Taipei, Taiwan (China); Cardiovascular Medical Center, Kaohsiung Veterans General Hospital, No. 386, Dar-Chung First Road, Kaohsiung, Taiwan (China)], E-mail: cpliu@isca.vghks.gov.tw; Wu, M.-T. [School of Medicine, National Yang-Ming University, Taipei, Taiwan (China); Department of Radiology, Kaohsiung Veterans General Hospital, No. 386, Dar-Chung First Road, Kaohsiung, Taiwan (China)], E-mail: wu.mingting@gmail.com; Mar, G.-Y. [Cardiovascular Medical Center, Kaohsiung Veterans General Hospital, No. 386, Dar-Chung First Road, Kaohsiung, Taiwan (China)], E-mail: gymar@isca.vghks.gov.tw; Lin, S.-K. [Cardiovascular Medical Center, Kaohsiung Veterans General Hospital, No. 386, Dar-Chung First Road, Kaohsiung, Taiwan (China)], E-mail: skyii89@yahoo.com.tw; Hsiao, S.-H. [Cardiovascular Medical Center, Kaohsiung Veterans General Hospital, No. 386, Dar-Chung First Road, Kaohsiung, Taiwan (China)], E-mail: a841120@ms3.hinet.net; Lin, S.-L. [School of Medicine, National Yang-Ming University, Taipei, Taiwan (China); Cardiovascular Medical Center, Kaohsiung Veterans General Hospital, No. 386, Dar-Chung First Road, Kaohsiung, Taiwan (China)], E-mail: sllin@isca.vghks.gov.tw; Chiou, K.-R. [School of Medicine, National Yang-Ming University, Taipei, Taiwan (China); Cardiovascular Medical Center, Kaohsiung Veterans General Hospital, No. 386, Dar-Chung First Road, Kaohsiung, Taiwan (China)], E-mail: krchiou@isca.vghks.gov.tw

    2010-01-15

    Background: Classifying acute coronary syndrome (ACS) as ST elevation ACS (STE-ACS) or non-ST elevation ACS (NSTE-ACS) is critical for clinical prognosis and therapeutic decision-making. Assessing the differences in composition and configuration of culprit lesions between STE-ACS and NSTE-ACS can clarify their pathophysiologic differences. Objective: This study focused on evaluating the ability of 64-slice multidetector computed tomography (MDCT) to investigate these differences in culprit lesions in patients with STE-ACS and NSTE-ACS. Methods: Of 161 ACS cases admitted, 120 who fit study criteria underwent MDCT and conventional coronary angiography. The following MDCT data were analyzed: calcium volume, Agatston calcium scores, plaque area, plaque burden, remodeling index, and plaque density. Results: The MDCT angiography had a good correlation with conventional coronary angiography regarding the stenotic severity of culprit lesions (r = 0.86, p < 0.001). The STE-ACS culprit lesions (n = 54) had significantly higher luminal area stenosis (78.6 {+-} 21.2% vs. 66.7 {+-} 23.9%, p = 0.006), larger plaque burden (0.91 {+-} 0.10 vs. 0.84 {+-} 0.12, p = 0.007) and remodeling index (1.28 {+-} 0.34 vs. 1.16 {+-} 0.22, p = 0.021) than those with NSTE-ACS (n = 66). The percentage of expanding remodeling index (remodeling index >1.05) was significantly higher in the STE-ACS group (81.5% vs. 63.6%, p = 0.031). The patients with STE-ACS had significantly lower MDCT density of culprit lesions than patients with NSTE-ACS (25.8 {+-} 13.9 HU vs. 43.5 {+-} 19.1 HU, p < 0.001). Conclusions: Sixty-four-slice MDCT can accurately evaluate the stenotic severity and composition of culprit lesions in selected patients with either STE-ACS or NSTE-ACS. Culprit lesions in NSTE-ACS patients had significantly lower luminal area stenosis, plaque burden, remodeling index and higher MDCT density, which possibly reflect differences in the composition of vulnerable culprit plaques and thrombi.

  6. Assessment of Grafts and Coronary Arteries with 64-slice Computer Tomography(CT) Angiography after Coronary Artery Bypass Surgery - our experiences

    OpenAIRE

    Veljanovska, Lidija; Sokolov, V.; Milev, Ivan; Idrizi, Spend; Mitrev, Zan

    2008-01-01

    The use of 64 slice CT (GE Light-Speed VCT) in evaluation of pathway and patency of the grafts, distal anastomosis and native vascular net in patients (pts) after coronary artery bypass grafting (CABG).

  7. Non-invasive Detection of Aortic and Coronary Atherosclerosis in Homozygous Familial Hypercholesterolemia by 64 Slice Multi-detector Row Computed Tomography Angiography

    Science.gov (United States)

    Homozygous familial hypercholesterolemia (HoFH) is a rare disorder characterized by the early onset of atherosclerosis, often at the ostia of coronary arteries. In this study we document for the first time that aortic and coronary atherosclerosis can be detected using 64 slice multiple detector-row ...

  8. Non-invasive detection of aortic and coronary atherosclerosis in homozygous familial hypercholesterolemia by 64 slice multi-detector row computed tomography angiography

    Science.gov (United States)

    Homozygous familial hypercholesterolemia (HoFH) is a rare disorder characterized by the early onset of atherosclerosis, often at the ostia of coronary arteries. In this study we document for the first time that aortic and coronary atherosclerosis can be detected using 64 slice multiple detector row ...

  9. Coronary calcium score as gatekeeper for 64-slice computed tomography coronary angiography in patients with chest pain: per-segment and per-patient analysis

    Energy Technology Data Exchange (ETDEWEB)

    Palumbo, Anselmo Alessandro; Cademartiri, Filippo [Azienda Ospedaliero-Universitaria di Parma, Non-Invasive Cardiovascular Imaging, Department of Radiology and Cardiology, Parma (Italy); Erasmus Medical Center, Department of Radiology and Cardiology, Rotterdam (Netherlands); Maffei, Erica; Martini, Chiara [Azienda Ospedaliero-Universitaria di Parma, Non-Invasive Cardiovascular Imaging, Department of Radiology and Cardiology, Parma (Italy); Tarantini, Giuseppe [University of Padua, Department of Cardiology, Padua (Italy); Di Tanna, Gian Luca; Berti, Elena; Grilli, Roberto [Regional Health Agency, Regione Emilia Romagna, Bologna (Italy); Casolo, Giancarlo [Ospedale Versilia, Department of Cardiology, Viareggio (Italy); Brambilla, Valerio [Don Gnocchi ONLUS, Cardiovascular Rehabilitation Unit, Parma (Italy); Cerrato, Marcella; Rotondo, Antonio [University of Naples, Department of Radiology, Naples (Italy); Weustink, Annick C.; Mollet, Nico R.A. [Erasmus Medical Center, Department of Radiology and Cardiology, Rotterdam (Netherlands)

    2009-09-15

    We sought to investigate the performance of 64-slice CT in symptomatic patients with different coronary calcium scores. Two hundred patients undergoing 64-slice CT coronary angiography for suspected coronary artery disease were enrolled into five groups based on Agatston calcium score using the Mayo Clinic risk stratification: group 1: score 0, group 2: score 1-10, group 3: score 11-100, group 4: score 101-400, and group 5: score > 401. Diagnostic accuracy for the detection of significant ({>=}50% lumen reduction) coronary artery stenosis was assessed on a per-segment and per-patient base using quantitative coronary angiography as the gold standard. For groups 1 through 5, sensitivity was 97, 96, 91, 90, 92%, and specificity was 99, 98, 96, 88, 90%, respectively, on a per-segment basis. On a per-patient basis, the best diagnostic performance was obtained in group 1 (sensitivity 100% and specificity 100%) and group 5 (sensitivity 95% and specificity 100%). Progressively higher coronary calcium levels affect diagnostic accuracy of CT coronary angiography, decreasing sensitivity and specificity on a per-segment base. On a per-patient base, the best results in terms of diagnostic accuracy were obtained in the populations with very low and very high cardiovascular risk. (orig.)

  10. Myocardial bridging of the right coronary artery inside the right atrial myocardium identified by ECG-gated 64-slice multidetector computed tomography angiography.

    Science.gov (United States)

    Chen, Chien-Cheng; Chen, Huan-Wu; Fu, Chen-Ju; Lin, Fen-Chiung; Wen, Ming-Shien; Liu, Yuan-Chang

    2010-01-01

    A myocardial bridge (MB) is defined as an intramyocardial course of a major epicardial coronary artery, and it is mainly confined to the left ventricle and the left anterior descending coronary artery. There are rare reports of right coronary MB seen during angiographic examination. Herein, we present a 49 year-old man with right coronary artery MB without luminal narrowing in the diastolic and systolic phases of electrocardiography-gated computed tomography images. The value of multi-detector computed tomography for the detection of anatomical variants in the cardiovascular system is further discussed. PMID:20438676

  11. Comparison of determinations of left atrial volume by the biplane area-length and Simpson's methods using 64-slice computed tomography

    International Nuclear Information System (INIS)

    There is increasing evidence that left atrial (LA) size is an important predictor of adverse cardiovascular outcomes such as atrial fibrillation, stroke, and congestive heart failure. The aim of this study was to determine whether there is a difference in results of quantification of LA volume by the area-length and Simpson's methods using multislice computed tomography (MSCT). The study population consisted of 51 patients with sinus rhythm (sinus group) and 20 patients with atrial fibrillation (af group) clinically indicated for MSCT angiography for evaluation of coronary arteries. Maximum LA volume, obtained at end-systole from the phase immediately preceding mitral valve opening, was measured using the area-length and Simpson's methods. In the sinus group, the mean LA volumes, indexed to body surface area, were 48.4±17.9 ml/m2 with the area-length method and 48.3±17.0 ml/m2 with the Simpson's method. In the af group, the mean indexed LA volumes with the area-length method and the Simposon's method were 91.5±47.5 ml/m2 and 90.3±45.9 ml/m2, respectively. LA volumes calculated by the area-length method exhibited a strong linear relationship and agreement with those calculated using Simpson's method in both the groups (sinus group: r=0.99, P<0.0001, af group: r=0.99, P<0.0001). The area-length method is a simple and reproducible means of assessment of LA volume. Standardization of LA volume assessment using MSCT is important for serial follow-up and meaningful communication of results of testing among institutions and physicians. (author)

  12. 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

    Institute of Scientific and Technical Information of China (English)

    施鸿毓; 陈晖; 仇兴标; 曲新凯; 方唯一

    2012-01-01

    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

  13. 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

    Institute of Scientific and Technical Information of China (English)

    肖云华; 吕富荣; 吕发金; 孙向前; 彭冈力

    2011-01-01

    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

  14. 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

    Institute of Scientific and Technical Information of China (English)

    陈华; 黄新苗; 赵仙先; 曹江; 秦永文

    2011-01-01

    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

  15. 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

    Institute of Scientific and Technical Information of China (English)

    唐烨真; 杜涛明; 唐光才; 兰永树; 涂永波; 林伟

    2013-01-01

    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.

  16. 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

    International Nuclear Information System (INIS)

    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 quality in subjects with

  17. 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

    Directory of Open Access Journals (Sweden)

    Roberto Rocha-e-Silva

    2007-01-01

    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

  18. 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

    Institute of Scientific and Technical Information of China (English)

    刘丽; 贺延; 王松涛; 吕俊刚

    2012-01-01

    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

  19. 2型糖尿病患者冠状动脉粥样硬化与视网膜病变的关系%Relationship Between Retinopathy and Coronary Atherosclerosis Determined by Coronary 64-Slice Multidetector Computed Tomography Angiography in Type 2 Diabetes

    Institute of Scientific and Technical Information of China (English)

    魏富春; 戎健; 陈玉群; 干雪梅; 于长青; 陈静; 杨沛; 陈金华

    2013-01-01

    Aim To evaluate the relationship between diabetic retinopathy (DR) and subclinical coronary atherosclerosis (CAs) on coronary 64-slice multidetector computed tomography angiography (MDCT) in individuals with type 2 diabetes mellitus.Methods From July 2007 to December 2009,114 and 124 type 2 diabetic patients with and without CAs were enrolled.They received fundus photochromy,coronary 64-slice multidetector computed tomography angiography,physical examination,and measurement of fasting plasma glucose (FPG),glycosylated haemoglobin (HbAlc),plasma lipid profile,estimated glomerular filtration rate (eGFR) and urinary albumin excretion rate (UAER).Then the analysis of the relationship among the detection and measurement outcomes were conducted.Results Diabetic patients with CAs had a higher prevalence of DR than those without CAs (67.5% vs 33.1%,P < 0.001).After adjustment for the traditional risk factors for cardiovascular disease,CAs was independently associated with DR (OR =5.0,95% CI 2.6~ 9.8).There was significant difference in the prevalence of CAs by the number of CAs vessels among patients without DR (NDR),those with pre-proliferative retinopathy (pre-PDR) and those with proliferative retinopathy (PDR) (P <0.01).The prevalences for CAs,the prevalences of CAs ≥3 vessels involved by plaque,and proportions of vessels with significant coronary plaque and of involved vessels in all detected coronary arteries were significantly increased with the presence and severity of DR (NDR vs Pre-PDR,Pre-PDR vs PDR,P < 0.01 for each).Conclusions The severity and extent of CAs were significantly increased with the incidence and progression of DR,and much of CAs and DR could be still multifactoral with common pathway.%目的 采用64层螺旋CT血管造影(MDCT),探讨2型糖尿病患者冠状动脉粥样硬化(CAs)与糖尿病视网膜病变(DR)的关系.方法 诊断为CAs的2型糖尿病患者114例,无CAs的患者124例,受试者均进行眼底彩色照相

  20. Calcium scoring using 64-slice MDCT, dual source CT and EBT : a comparative phantom study

    NARCIS (Netherlands)

    Groen, Jaap M.; Greuter, Marcel J. W.; Vliegenthart, R.; Suess, C.; Schmidt, B.; Zijlstra, F.; Oudkerk, M.

    2008-01-01

    Purpose Assessment of calcium scoring (Ca-scoring) on a 64-slice multi-detector computed tomography (MDCT) scanner, a dual-source computed tomography (DSCT) scanner and an electron beam tomography (EBT) scanner with a moving cardiac phantom as a function of heart rate, slice thickness and calcium de

  1. Calcium scoring using 64-slice MDCT, dual source CT and EBT: a comparative phantom study

    OpenAIRE

    Groen, Jaap M.; Greuter, Marcel J. W.; Vliegenthart, R.; Suess, C.; Schmidt, B.; Zijlstra, F.; Oudkerk, M.

    2007-01-01

    Purpose Assessment of calcium scoring (Ca-scoring) on a 64-slice multi-detector computed tomography (MDCT) scanner, a dual-source computed tomography (DSCT) scanner and an electron beam tomography (EBT) scanner with a moving cardiac phantom as a function of heart rate, slice thickness and calcium density. Methods and materials Three artificial arteries with inserted calcifications of different sizes and densities were scanned at rest (0 beats per minute) and at 50–110 beats per minute (bpm) w...

  2. Influence of heart rate on image quality of 64-slice spiral computed coronary angiography and optimization on reconstruction of phase window

    International Nuclear Information System (INIS)

    Objective: To evaluate the influence of heart rate on the image quality of 64-slice spiral computed coronary angiography (MSCTCA) and optimize the image reconstruction window. Methods: According to the heart rate, 86 patients were classified into 5 groups: group A, the heart rate ≤60 beat per minute(BMP); group B,61-70BMP, group C,71-80BMP, and group D>80BMP. The image quality of MSCTCA was scored 5 grades from 1-5 according to heart motion artifact. The influences of heart rate and reconstruction phase on the image quality of MSCTCA were evaluated. Results: Average heart rate was 64.4 ±10.1BMP. Diagnostic image quality (score>3) was attained in 277 of 344 segments at the best reconstruction interval. There was a significant corxelation between average heart rate and image quality, but there was no difference between relative delay (%) reconstruction and absolute delay (ms) reconstruction on the image quality. Conclusion: Reducing average heart rate is beneficial for improving the image quality. (authors)

  3. Bouveret’s Syndrome: 64-Slice CT Diagnosis and Surgical Management—A Case Report

    Directory of Open Access Journals (Sweden)

    Dinesh Sharma

    2012-01-01

    Full Text Available Gastric outlet obstruction caused by duodenal impaction of a large gallstone migrated through a cholecystoduodenal fistula has been referred to as Bouveret’s syndrome. We present a case of gallstone-induced duodenal obstruction in an elderly female patient, diagnosed on a 64-slice MDCT scanner. One-stage surgery, that is, stone removal and cholecystectomy, was performed resulting in relief of obstruction and complete cure. Clinical features, multidetector computed tomography (MDCT findings, and surgical management are discussed.

  4. Coronary artery dissection with rupture of aortic valve commissure following type A aortic dissection: the role of 64-slice MDCT.

    Science.gov (United States)

    Das, K M; Abdou, Sayed M; El-Menyar, Ayman; Ayman, El Menyar; Khulaifi, A A; Nabti, A L

    2008-01-01

    A rare case of bilateral coronary artery dissection with rupture of aortic valve commissure following type A aortic dissection is described. 64-slice multidetector computed tomography (MDCT) was able to demonstrate both this findings along with involvement of other neck vessels. TEE demonstrated the severity and mechanisms of aortic valve damage and assisted the surgeon in valve repair. MDCT has played an invaluable role in the diagnosis of the abnormal details of such life-threatening vascular complications. PMID:18384568

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

    Directory of Open Access Journals (Sweden)

    Alpa Bharati

    2012-01-01

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

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

    LENUS (Irish Health Repository)

    Ryan, E Ronan

    2012-02-01

    A 41-year-old man collapsed after lifting weights at a gym. Following admission to the emergency department, a 64-slice cardiac computed tomography (CT) revealed a Stanford Type A aortic dissection arising from a previous coarctation repair. Multiphasic reconstructions demonstrated an unstable, highly mobile aortic dissection flap that extended proximally to involve the right coronary artery ostium. Our case is an example of the application of electrocardiogram-gated cardiac CT in directly visualizing involvement of the coronary ostia in acute aortic dissection, which may influence surgical management.

  7. Influence of intra-coronary enhancement on diagnostic accuracy with 64-slice CT coronary angiography

    Energy Technology Data Exchange (ETDEWEB)

    Cademartiri, Filippo [Azienda Ospedaliero-Universitaria di Parma, Department of Radiology and Cardiology, Parma (Italy); Erasmus Medical Center, Department of Radiology and Cardiology, Rotterdam (Netherlands); Azienda Ospedaliero-Universitaria di Parma, Non-invasive Cardiovascular Imaging Unit, Department of Radiology, Parma (Italy); Maffei, Erica; Aldrovandi, Annachiara; Fusaro, Michele; Vignali, Luigi; Menozzi, Alberto [Azienda Ospedaliero-Universitaria di Parma, Department of Radiology and Cardiology, Parma (Italy); Palumbo, Anselmo A. [Azienda Ospedaliero-Universitaria di Parma, Department of Radiology and Cardiology, Parma (Italy); Erasmus Medical Center, Department of Radiology and Cardiology, Rotterdam (Netherlands); Malago, Roberto [University of Verona, Department of Radiology, Verona (Italy); La Grutta, Ludovico; Midiri, Massimo [University of Palermo, Department of Radiology, Palermo (Italy); Meiijboom, W.B.; Mollet, Nico R.A.; Krestin, Gabriel P. [Erasmus Medical Center, Department of Radiology and Cardiology, Rotterdam (Netherlands); Brambilla, Valerio; Coruzzi, Paolo [Don Gnocchi ONLUS, Cardiovascular Rehabilitation Unit, Parma (Italy); Kirchin, Miles A. [Bracco Imaging SpA, Worldwide Medical and Regulatory Affairs, Milan (Italy)

    2008-03-15

    We assessed the effect of intra-coronary attenuation on diagnostic accuracy using 64-slice computed tomography coronary angiography (CT-CA). We enrolled 170 patients with suspected coronary artery disease who underwent conventional coronary angiography (CA) and 64-slice CT-CA (100 ml of Iomeprol 400 mg I/ml at 4 ml/s). The study population was divided into two groups (85 patients each based on median attenuation of 326 HU) based on mean arterial attenuation; group 1 with low attenuation and group 2 with high attenuation. Diagnostic accuracy for the detection of significant coronary artery stenosis was determined for both groups using CA as reference standard. Overall, 163 significant stenoses were detected in 1,030 assessable coronary artery segments in group 1 compared with 160 significant stenoses in 1,020 assessable segments in group 2. The average intra-coronary attenuation was significantly (P < 0.05) higher for group 2 (388 {+-} 46 HU) compared with group 1 (291 {+-} 33 HU). The corresponding sensitivity and specificity values for detection of significant coronary artery stenosis were higher for group 2 (96.3% and 97.6%, respectively) than for group 1 (82.8% and 93.2%, respectively) and were more marked in distal coronary segments than in proximal segments. Higher intra-coronary attenuation on CT-CA results in greater diagnostic accuracy for detection of coronary artery stenosis. (orig.)

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

    DEFF Research Database (Denmark)

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

    2012-01-01

    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....

  9. Radiation Exposure of Ovarian Cancer Patients: Contribution of CT Examinations Performed on Different MDCT (16 and 64 Slices) Scanners and Image Quality Evaluation

    OpenAIRE

    Rizzo, S; D. Origgi; Brambilla, S.; Maria, F.; Foà, R; Raimondi, S; N. Colombo; Bellomi, M.

    2015-01-01

    Abstract The objective of this study is to compare radiation doses given to ovarian cancer patients by different computed tomographies (CTs) and to evaluate association between doses and subjective and objective image quality. CT examinations included were performed either on a 16-slice CT, equipped with automatic z-axis tube current modulation, or on a 64-slice CT, equipped with z-axis, xy-axis modulation, and adaptive statistical iterative algorithm (ASIR). Evaluation of dose included the f...

  10. 64-slice multidetector coronary CT angiography: in vitro evaluation of 68 different stents

    Energy Technology Data Exchange (ETDEWEB)

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

    2006-04-15

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

  11. Radiation exposure of ovarian cancer patients: contribution of CT examinations performed on different MDCT (16 and 64 slices) scanners and image quality evaluation: an observational study.

    Science.gov (United States)

    Rizzo, Stefania; Origgi, Daniela; Brambilla, Sarah; De Maria, Federica; Foà, Riccardo; Raimondi, Sara; Colombo, Nicoletta; Bellomi, Massimo

    2015-05-01

    The objective of this study is to compare radiation doses given to ovarian cancer patients by different computed tomographies (CTs) and to evaluate association between doses and subjective and objective image quality.CT examinations included were performed either on a 16-slice CT, equipped with automatic z-axis tube current modulation, or on a 64-slice CT, equipped with z-axis, xy-axis modulation, and adaptive statistical iterative algorithm (ASIR). Evaluation of dose included the following dose descriptors: volumetric CT dose index (CTDIvol), dose length product (DLP), and effective dose (E). Objective image noise was evaluated in abdominal aorta and liver. Subjective image quality was evaluated by assessment of image noise, spatial resolution and diagnostic acceptability.Mean and median CTDIvol, DLP, and E; correlation between CTDIvol and DLP and patients' weight; comparison of objective noise for the 2 scanners; association between dose descriptors and subjective image quality.The 64-slice CT delivered to patients 24.5% lower dose (P descriptors (CTDIvol, DLP, E) and weight (P descriptors and image noise for the 64-slice CT, and between dose descriptors and spatial resolution for the 16-slice CT.Current dose reduction systems may reduce radiation dose without significantly affecting image quality and diagnostic acceptability of CT exams. PMID:25929914

  12. 64-slice spiral CT in the diagnosis of Caroli disease

    International Nuclear Information System (INIS)

    Objective: To investigate the value of 64-slice spiral CT in the diagnosis of Caroli disease. Methods: 64-slice spiral CT of 15 patients with histologically proven Caroli disease was reviewed. Results: All cases were polycystic or multi-tubular hypodensities in the livers communicating with intrahepatic bile ducts. There was no contrast enhancement. The central dot sign was detected on 2 patients. Of 12 patients with type I disease, ancillary findings included multiple hemangiomas and small cysts in the liver (2), bile duct stones (4), pneumobilia (3), and cholangitis (1). Of the remaining 3 patients with type II disease, two had liver cirrhosis and the other cholangitis with periportal fibrosis. Conclusion: 64 slice spiral CT with multiplanar reconstruction allows clear depiction of cystic liver lesions and their relationship with intrahepatic bile ducts. It is valuable in the diagnosis of Caroli disease. (authors)

  13. Computed Tomography (CT) -- Sinuses

    Science.gov (United States)

    ... Physician Resources Professions Site Index A-Z Computed Tomography (CT) - Sinuses Computed tomography (CT) of the sinuses ... CT of the Sinuses? What is CT (Computed Tomography) of the Sinuses? Computed tomography, more commonly known ...

  14. Computed Tomography (CT) -- Sinuses

    Medline Plus

    Full Text Available ... Physician Resources Professions Site Index A-Z Computed Tomography (CT) - Sinuses Computed tomography (CT) of the sinuses ... CT of the Sinuses? What is CT (Computed Tomography) of the Sinuses? Computed tomography, more commonly known ...

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2010-11-15

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

  16. Measurement of scattered radiation in a volumetric 64-slice CT scanner using three experimental techniques

    Energy Technology Data Exchange (ETDEWEB)

    Akbarzadeh, A; Ay, M R; Sarkar, S [Department of Medical Physics and Biomedical Engineering, Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of); Ghadiri, H [Research Center for Science and Technology in Medicine, Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of); Zaidi, H [Division of Nuclear Medicine, Geneva University Hospital, CH-1211 Geneva (Switzerland)], E-mail: mohammadreza_ay@tums.ac.ir

    2010-04-21

    Compton scatter poses a significant threat to volumetric x-ray computed tomography, bringing cupping and streak artefacts thus impacting qualitative and quantitative imaging procedures. To perform appropriate scatter compensation, it is necessary to estimate the magnitude and spatial distribution of x-ray scatter. The aim of this study is to compare three experimental methods for measurement of the scattered radiation profile in a 64-slice CT scanner. The explored techniques involve the use of collimator shadow, a single blocker (a lead bar that suppresses the primary radiation) and an array blocker. The latter was recently proposed and validated by our group. The collimator shadow technique was used as reference for comparison since it established itself as the most accurate experimental procedure available today. The mean relative error of measurements in all tube voltages was 3.9 {+-} 5.5% (with a maximum value of 20%) for the single blocker method whereas it was 1.4 {+-} 1.1% (with a maximum value of 5%) for the proposed blocker array method. The calculated scatter-to-primary ratio (SPR) using the blocker array method for the tube voltages of 140 kVp and 80 kVp was 0.148 and 1.034, respectively. For a larger polypropylene phantom, the maximum SPR achieved was 0.803 and 6.458 at 140 kVp and 80 kVp, respectively. Although the three compared methods present a reasonable accuracy for calculation of the scattered profile in the region corresponding to the object, the collimator shadow method is by far the most accurate empirical technique. Nevertheless, the blocker array method is relatively straightforward for scatter estimation providing minor additional radiation exposure to the patient.

  17. Myocardial Bridging of the Right Coronary Artery inside the Right Atrial Myocardium Identified by ECG-gated 64-slice Multidetector Computed Tomography Angiography

    OpenAIRE

    Yung-Liang Wan; Ming-Shien Wen; Fen-Chiung Lin; Chen-Ju Fu; Huan-Wu Chen; Chien-Cheng Chen; Yuan-Chang Liu

    2010-01-01

    A myocardial bridge (MB) is defined as an intramyocardial course of a major epicardialcoronary artery, and it is mainly confined to the left ventricle and the left anterior descendingcoronary artery. There are rare reports of right coronary MB seen during angiographicexamination. Herein, we present a 49 year-old man with right coronary artery MB withoutluminal narrowing in the diastolic and systolic phases of electrocardiography-gated computedtomography images. The value of multi-detector com...

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

    Directory of Open Access Journals (Sweden)

    Randolf Klingebiel

    2008-08-01

    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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2015-08-15

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

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

    International Nuclear Information System (INIS)

    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.

  1. Computed Tomography (CT) -- Head

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    Full Text Available ... Physician Resources Professions Site Index A-Z Computed Tomography (CT) - Head Computed tomography (CT) of the head uses special x-ray ... What is CT Scanning of the Head? Computed tomography, more commonly known as a CT or CAT ...

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

    International Nuclear Information System (INIS)

    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.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2011-08-15

    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.

  4. Stress Computed Tomography Myocardial Perfusion Imaging: A New Topic in Cardiology.

    Science.gov (United States)

    Seitun, Sara; Castiglione Morelli, Margherita; Budaj, Irilda; Boccalini, Sara; Galletto Pregliasco, Athena; Valbusa, Alberto; Cademartiri, Filippo; Ferro, Carlo

    2016-02-01

    Since its introduction about 15 years ago, coronary computed tomography angiography has become today the most accurate clinical instrument for noninvasive assessment of coronary atherosclerosis. Important technical developments have led to a continuous stream of new clinical applications together with a significant reduction in radiation dose exposure. Latest generation computed tomography scanners (≥ 64 slices) allow the possibility of performing static or dynamic perfusion imaging during stress by using coronary vasodilator agents (adenosine, dipyridamole, or regadenoson), combining both functional and anatomical information in the same examination. In this article, the emerging role and state-of-the-art of myocardial computed tomography perfusion imaging are reviewed and are illustrated by clinical cases from our experience with a second-generation dual-source 128-slice scanner (Somatom Definition Flash, Siemens; Erlangen, Germany). Technical aspects, data analysis, diagnostic accuracy, radiation dose and future prospects are reviewed. PMID:26774540

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

    Institute of Scientific and Technical Information of China (English)

    Yong-Shu Gao; Xing-Can Ma

    2015-01-01

    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.

  6. Computed Tomography (CT) -- Head

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    Full Text Available ... Videos related to Computed Tomography (CT) - Head About this Site RadiologyInfo.org is produced by: Please note ... you can search the ACR-accredited facilities database . This website does not provide cost information. The costs ...

  7. Computed Tomography (CT) -- Sinuses

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    Full Text Available ... Images related to Computed Tomography (CT) - Sinuses About this Site RadiologyInfo.org is produced by: Please note ... you can search the ACR-accredited facilities database . This website does not provide cost information. The costs ...

  8. Computed Tomography (CT) -- Sinuses

    Medline Plus

    Full Text Available Toggle navigation Test/Treatment Patient Type Screening/Wellness Disease/Condition Safety En Español More Info Images/Videos News Physician Resources Professions Site Index A-Z Computed Tomography (CT) - Sinuses ...

  9. Computed Tomography (CT) -- Head

    Medline Plus

    Full Text Available Toggle navigation Test/Treatment Patient Type Screening/Wellness Disease/Condition Safety En Español More Info Images/Videos News Physician Resources Professions Site Index A-Z Computed Tomography (CT) - Head ...

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

    Energy Technology Data Exchange (ETDEWEB)

    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)

    2007-07-15

    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.)

  11. 64-slice CT imaging in a case of total anomalous pulmonary venous circulation

    International Nuclear Information System (INIS)

    For long, catheter angiography has been the investigation of choice for the diagnosis of congenital anomalies of the heart such as total anomalous pulmonary venous circulation (TAPVC). In the last few years, MRI and multislice CT scan have also been introduced for this purpose. We report a case where 64-slice CT scan was found very useful in the evaluation of TAPVC

  12. Neutron Computed Tomography

    International Nuclear Information System (INIS)

    Computed tomography is a non-destructive testing method which can visualize cross-section of materials based on their nuclear characteristics. In the previous work, X-ray was used as its radiation media. The aim of this experiment was to improve the computed tomography technique using neutron beam. For reconstructing the cross-section image of materials, a filtered back projection was used. Result indicated that a minimum hole shown was 3 mm in diameter using a black and white presentation. While using eight colour levels, a hole of 2 mm in diameter could be seen clearly. It is expected that neutron computed tomography can improve the results of non-destructive testing. (author). 5 refs., 6 figs

  13. Optimizing 64-slice spiral CT angiography in lower extremity arterial disease with individualized injection protocol

    International Nuclear Information System (INIS)

    Objective: To explore the optimal protocol of the 64-slice spiral CT angiography (CTA) in lower extremity arterial disease. Methods: Forty -eight patients with clinically suspected lower extremity arterial disease underwent GE LightSpeed VCT using individual and traditional injection protocols. The clinical value of CTA was evaluated using DSA as the standard reference. Results: Satisfactory images were obtained from 47 of 48 cases. Images fulfilling clinical diagnostic requirements after appropriate post -procession on workstation were obtained from 1 case. The image quality of the group with the individualized injection protocol was significantly superior to that of the group with the traditional image protocol. The sensitivity and specificity of CTA in detecting middle-grade and severe arterial stenosis were 86.1% and 86.6%, respectively. Conclusion: 64-slice spiral CT angiography is a reliable method for evaluating the lower extremity arterial disease, and is a more ideal method if using individualized injection protocol. (authors)

  14. The Measurement of Opening Angle and Orifice Area of a Bileaflet Mechanical Valve Using Multidetector Computed Tomography

    OpenAIRE

    Lee, Dong-Hyeon; Youn, Ho-Joong; Shim, Sung-Bo; Lee, Sun-Hee; Jung, Jung-Im; Jung, Seung-Eun; Choi, Yun-Seok; Park, Chul-Soo; Oh, Yong-Seog; Chung, Wook-Sung; Kim, Jae-Hyung

    2009-01-01

    Background and Objectives The aim of this study was to assess mechanical valve function using 64-slice multidetector computed tomography (MDCT). Subjects and Methods In 20 patients (mean age, 50±12 years; male-to-female ratio, 10:10), 30 St. Jude bileaflet mechanical valves (15 aortic and 15 mitral valves) were evaluated using MDCT. We selected images vertical and parallel to the mechanical valve. The valve orifice area (OA) and valve length were determined by manual tracing and the opening a...

  15. Chest computed tomography

    DEFF Research Database (Denmark)

    Loeve, Martine; Krestin, Gabriel P.; Rosenfeld, Margaret;

    2013-01-01

    are not suitable to study CF lung disease in young children. Chest computed tomography (CT) holds great promise for use as a sensitive surrogate endpoint in CF. A large body of evidence has been produced to validate the use of chest CT as primary endpoint to study CF lung disease. However, before chest CT can...

  16. Computed Tomography (CT) -- Sinuses

    Medline Plus

    Full Text Available ... Computed tomography (CT) of the sinuses uses special x-ray equipment to evaluate the paranasal sinus cavities – hollow, ... is a diagnostic medical test that, like traditional x-rays, produces multiple images or pictures of the inside ...

  17. Computed Tomography (CT) -- Head

    Medline Plus

    Full Text Available ... Computed tomography (CT) of the head uses special x-ray equipment to help assess head injuries, severe headaches, ... is a diagnostic medical test that, like traditional x-rays, produces multiple images or pictures of the inside ...

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

    Energy Technology Data Exchange (ETDEWEB)

    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)

    2011-09-15

    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. Children's (Pediatric) CT (Computed Tomography)

    Medline Plus

    Full Text Available ... Site Index A-Z Children's (Pediatric) CT (Computed Tomography) Pediatric computed tomography (CT) is a fast, painless exam that uses ... of Children's CT? What is Children's CT? Computed tomography, more commonly known as a CT or CAT ...

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

    Institute of Scientific and Technical Information of China (English)

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

    2011-01-01

    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.

  1. Diagnostic value of 64-slice CT angiography in coronary artery disease: A systematic review

    International Nuclear Information System (INIS)

    Purpose: To perform a systematic review of the diagnostic value of 64-multislice CT (MSCT) angiography in the detection of coronary artery disease (CAD) when compared to conventional coronary angiography. Materials and methods: A search of PUBMED and MEDLINE databases for English literature was performed. Only studies with at least 10 patients comparing 64-slice MSCT angiography with conventional coronary angiography in the detection of CAD were included. Diagnostic value of MSCT angiography compared to coronary angiography was compared and analysed at segment-, vessel- and patient-based assessment. Results: Fifteen studies met selection criteria and were included for analysis. Pooled sensitivity, specificity, positive predictive value and negative predictive value as well as 95% confidence interval (CI) were 97% (94 and 99%), 88% (79 and 97%), 94% (91 and 97%), and 95% (90 and 99%) for patient-based assessment; 92% (85 and 99%), 92% (85 and 99%), 78% (66 and 91%) and 98% (96 and 99%) for vessel-based assessment; 90% (85 and 94%), 96% (95 and 97%), 75%(68 and 82%) and 98% (98 and 99%) for segment-based assessment, respectively. No significant difference was found in the diagnostic accuracy of 64-slice CT in the detection of CAD when comparison was performed either among four main coronary arteries, or between proximal and middle or distal segments (p > 0.05). Conclusion: Our results showed that 64-slice CT angiography has a high-diagnostic value in the detection of CAD. Severe coronary artery calcification seems to be the major factor affecting the visualisation and assessment

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

    Energy Technology Data Exchange (ETDEWEB)

    Marini, Davide; Agnoletti, Gabriella [Centre de Reference Malformations Cardiaques Congenitales Complexes-M3C, Universite Paris Descartes, UFR Necker-Enfants Malades, Paris (France); Brunelle, Francis [University Paris Descartes, UFR Necker-Enfants Malades, Department of Pediatric Radiology, APHP, Paris (France); Sidi, Daniel; Bonnet, Damien [Centre de Reference Malformations Cardiaques Congenitales Complexes-M3C, Universite Paris Descartes, UFR Necker-Enfants Malades, Paris (France); Ou, Phalla [Centre de Reference Malformations Cardiaques Congenitales Complexes-M3C, Universite Paris Descartes, UFR Necker-Enfants Malades, Paris (France); University Paris Descartes, UFR Necker-Enfants Malades, Department of Pediatric Radiology, APHP, Paris (France)], E-mail: phalla.ou@nck.aphp.fr

    2009-09-15

    Objective: The purpose of this study was to compare the diagnostic accuracy of 64-slice CT with that of invasive angiography in the detection of graft and/or coronary angioplasty stenosis in children who had undergone coronary artery surgery. Population and methods: Fifteen consecutive children (8 male and 7 female; age 9.2 {+-} 6.1 years) underwent 64-slice CT because of chest pain or ECG changes mean 4.8 {+-} 3.7 years after surgical coronary artery surgery; 10 patients had coronary angioplasty using a patch from the saphenous vein, four had mammary artery bypass, and one had saphenous vein bypass. Six main segments of the coronary arteries and all the bypass graft considered as a single segment were analyzed and compared with invasive angiography used as the reference standard. Results: CT correctly identified the four children with coronary angioplasty and mammary graft lesions that were confirmed by conventional angiography: one patient had a significant stenosis (>50% stenosis) at the mammary bypass graft anastomosis site; three other had non-significant stenosis (<50% stenosis) including a mild lesion of the saphenous vein patch in two patients and a mild lesion at the anastomosis site of the mammary bypass in one. All segments identified as normal by CT in the other 11 children were also found to be normal by conventional angiography. Conclusion: In centers expert in this technique, 64-slice CT scanning is a promising, rapid, and useful diagnostic technique for evaluating both coronary angioplasty and bypass graft lesions in children who had undergone coronary artery surge0008.

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

    International Nuclear Information System (INIS)

    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

  4. 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

    International Nuclear Information System (INIS)

    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

  5. Multiplanner spine computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Chung, H. K.; Jeon, H. J.; Hong, K. C.; Chung, K. B.; Suh, W. H. [Korea University College of Medicine, Seoul (Korea, Republic of)

    1983-06-15

    The computed tomography is useful in evaluation of bony structures and adjacent soft tissues of the spine. Recently, the multiplanar spine CT scan is highly superior than usual axial scan, because of easily demonstrable longitudinal dimension, level of spine and spinal canal. We evaluated 62 cases of spine CT, whom complains of spinal symptoms, from July, 1982 to January, 1983. The results were as follows: 1. The sex distribution of cases were 45 male and 17 female, ages were from 15 years to 76 years, and sites were 15 cervical spine, 7 thoracic spine, 42 lumbar spine and 21 sacral spine. 2. Sixty two cases of the CT diagnosis were reviewed and shows 19 cases of herniated intervertebral disc, 7 cases of spine fracture, 5 cases of degenerative disease, 4 cases of metastatic cancer, 2 cases of posterior longitudinal ligament ossification, 1 case of cord injury and 24 cases of normal. 3. The CT findings of herniated intervertebral disc were protruding disc, obliteration of anterior epidural fat, with or without indentation of dural sac and calcification within posterior disc margin. In cases of trauma, the multiplanar spine CT scan detects more specific extension of the fracture sites, and it is able to demonstrate relationship between fracture fragment and spinal cord, therefore operability can be decided. In case of posterior longitudinal ligament ossification, it is easy to demonstrate linear high density along posterior margin of vertebral bodies on sagittal reconstruction scan. 4. The computed tomography is diagnostic in detection of spinal disease. However, multiplanar spine CT is more diagnostic than axial computed tomography such as detecting the longitudinal dimension and demonstration of spinal canal.

  6. Computed tomography device

    International Nuclear Information System (INIS)

    A computed tomography device comprising a subtraction unit which obtains differential data strings representing the difference between each time-serial projection data string of a group of projection data strings corresponding to a prospective reconstruction image generated by projection data strings acquired by a data acquisition system, a convolution unit which convolves each time-serial projection data string of the group of projection data strings corresponding to the prospective reconstruction image, and a back-projection unit which back-projects the convolved data strings

  7. Stored Luminescence Computed Tomography

    CERN Document Server

    Cong, Wenxiang; Wang, Ge

    2013-01-01

    The phosphor nanoparticles made of doped semiconductors, pre-excited by well-collimated X-ray radiation, were recently reported for their light emission upon NIR light stimulation. The characteristics of X-ray energy storage and NIR stimulated emission is highly desirable to design targeting probes and improve molecular and cellular imaging. Here we propose stored luminescence computed tomography (SLCT), perform realistic numerical simulation, and demonstrate a much-improved spatial resolution in a preclinical research context. The future opportunities are also discussed along this direction.

  8. The clinical application of 64-slice spiral CT angiography in carotid artery bifurcation disease

    International Nuclear Information System (INIS)

    Objective: To explore the clinical value of 64-slice spiral CT angiography (CTA) in carotid stenosis and atherosclerotic plaque. Methods: 40 patients (80 carotid arteries) underwent CTA and DSA. These two examinations within one week. The results of CTA were compared with that of DSA, the sensitivity and specificity of CTA and DSA were figured out. Results: CTA performed well in the detection of mild (0% to 29%) carotid stenosis, as well as carotid occlusion, with values for sensitivity and specificity both near 100%. In determining that a stenosis was >50% by DSA measurement, CTA with a sensitivity, specificity of 89% and 91% respectively. While CTA was quite specific in identifying degrees of stenoses in either the 50% to 69% or the 70% to 99% ranges, in this task it was much less sensitive: 65% and 73% respectively. CTA can detect all kinds of ulcers while DSA can not. Conclusions: 64-slice CTA and DSA were correctly identified in detecting carotid stenosis. CTA could demonstrate ulcers associated with the carotid stenosis, hut DSA only show stenosis. (authors)

  9. Multislice computed tomography coronary angiography

    OpenAIRE

    Cademartiri, Filippo

    2005-01-01

    markdownabstract__Abstract__ Computed Tomography (CT) imaging is also known as "CAT scanning" (Computed Axial Tomography). Tomography is from the Greek word "tomos" meaning "slice" or "section" and "graphia" meaning "describing". CT was invented in 1972 by British engineer Godfrey Hounsfield of EMI Laboratories, England, and independently by South Mrican born physicist Allan Cormack of Tufts University, Massachusetts.1 • 2 Hounsfield was later awarded the Nobel Peace Prize and honoured with K...

  10. Clinical value of 64-slice spiral CT for classification of femoral neck fracture

    International Nuclear Information System (INIS)

    Objective: To evaluate the clinical application of 64-slice spiral CT for classification of femoral neck fracture. Methods: The survey was comprised of 46 patients with femoral neck fractures detected with plain radiographs and CT images. Cases were randomly presented in 2 formats: plain radiographs and CT. Garden classification was queried. Modification of garden classification (nondisplaced vs displaced) was taken to compare with plain radiographs and CT in the study. Results: The results of classification for plain radiographs were 2 cases of Garden Ⅰ, 10 cases of Ⅱ, 22 cases of Ⅲ, and 12 cases of Ⅳ. Those for CT were 1 cases of Garden Ⅰ, 4 cases of Ⅱ, 26 cases of Ⅲ, and 15 cases of Ⅳ. CT improved the accuracy of Garden Classification (P<0.05). Conclusion: Garden classification using CT images shows good conformation with results of surgery. 64-Slic CT is better plain radiographs for Garden classification of femoral neck fracture. (authors)

  11. Coronary artery imaging with 64-slice spiral CT in atrial fibrillation patients: initial experience

    International Nuclear Information System (INIS)

    Objective: To discuss the clinical value of coronary artery imaging using 64-slice spiral CT in patient with atrial fibrillation. Methods: The images of 31 patients with atrial fibrillation who underwent contrast-enhanced CT coronary angiography were evaluated. The presence of stenosis on each segment of coronary arteries was recorded and their degree of stenosis was measured using the vessel analysis software. Ten patients additionally underwent conventional coronary angiography. The results of conventional coronary angiography were compared with CT coronary angiography of the 10 patients. Results: Image reconstruction was based on absolute timing. The image quality of 364 coronary vessel segments on the images from 31 patients was evaluated and defined as excellent, fine, moderate or poor. The image quality was excellent, fine, moderate and poor in 85, 41, 5, and 8 vessel segments respectively in patient group with heart rate between 47 beat per minent (bpm) and 69 bpm; and in 63, 16, 13, and 15 vessel segments respectively in patent group with heart rate between 70 bpm and 79 bpm;and in 46, 25, 23, and 24 vessel segments in patient group with heart rate between 80 bpm and 105 bpm. There was significant difference among the three patient groups (H=22.08, P<0.01). Comparison was carried out between CT angiographic findings and conventional angiographic findings of the 125 segments of the coronary arteries in the 10 patients who underwent conventional coronary angiography. The sensitivity and specificity of CT angiography for diagnosing vessel with significant coronary stenosis (≥50% narrowing) was 85.0% (17/20) and 95.2% (100/105), respectively. Positive predictive value was 77.3% (17/22), and negative predictive value was 97.1% (100/103). Coronary CTA underestimated the lesions of 3 vessel segments and overestimated the lesions of 5 vessel segments. Conclusion: Coronary artery imaging with 64-slice row CT had clinical value for patients with atrial fibrillation

  12. Spinal computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Sartor, K.

    1980-10-01

    Computed tomography (CT) of the spine and spinal cord is gaining more and more importance as a valuable investigative method in neuroradiology. Performed as a noninvasive procedure, with or without intravenous contrast enhancement, it can be used to diagnose paravertebral soft tissue lesions, constrictive lesions of the bony spinal canal, structure changes of the vertebral column or of individual vertebrae, vascular intraspinal lesions, and intraspinal tumors with abnormally high or abnormally low attenuation values. Performed as an invasive procedure, after intrathecal introduction of metrizamide, spinal CT can in selected cases be used in conjunction with conventional metrizamide myelography as an additional procedure (secondary CT-myelography) or even as initial procedure ( primary CT-myelography), taking advantage of its unique properties, namely to provide a transverse axial image of the spine and related soft tissue structures and to detect even small differences in density. Further improvement of spinal CT, particularly the routine non-invasive demonstration of the intraspinal soft tissues, is to be expected.

  13. Computed tomography apparatus

    International Nuclear Information System (INIS)

    In fan-beam computed tomography apparatus, timing reference pulses, normally occurring at intervals t, for data transfer and reset of approx. 500 integrators in the signal path from the detector array, are generated from the scan displacement, e.g. using a graticule and optical sensor to relate the measurement paths geometrically to the body section. Sometimes, a slow scan rate is required to provide a time-averaged density image, e.g. for planning irradiation therapy, and then the sensed impulses will occur at extended intervals and can cause integrator overload. An improvement is described which provides a pulse generator which responds to a reduced scan rate by generating a succession of further transfer and reset pulses at intervals approximately equal to t starting a time t after each timing reference pulse. Then, using an adding device and RAM, all the transferred signals integrated in the interval t' between two successive slow scan reference pulses are accumulated in order to form a corresponding measurement signal. (author)

  14. Coronary calcium mass scores measured by identical 64-slice MDCT scanners are comparable : a cardiac phantom study

    NARCIS (Netherlands)

    Dijkstra, Hildebrand; Greuter, Marcel J. W.; Groen, Jaap M.; Vliegenthart-Proenca, Rozemarijn; Renema, KlaasJan W. K.; de Lange, Frank; Oudkerk, Matthijs

    2010-01-01

    To assess whether absolute mass scores are comparable or differ between identical 64-slice MDCT scanners of the same manufacturer and to compare absolute mass scores to the physical mass and between scan modes using a calcified phantom. A non-moving anthropomorphic phantom with nine calcifications o

  15. In vitro imaging of coronary artery stents: Are there differences between 16- and 64-slice CT scanners?

    International Nuclear Information System (INIS)

    Purpose: To compare the performance of 64-slice with 16-slice CT scanners for the in vitro evaluation of coronary artery stents. Methods and materials: Twelve different coronary artery stents were placed in the drillings of a combined heart and chest phantom, which was scanned with a 16- and 64-slice CT scanner. Coronal reformations were evaluated for artificial lumen narrowing, intraluminal attenuation values, and false widening of the outer stent diameter as an indicator of artifacts outside the stent. Results: Mean artificial lumen narrowing was not significantly different between the 16- and 64-slice CT scanner (44% versus 39%; p = 0.408). The differences between the Hounsfield Units (HU) measurements inside and outside the stents were significantly lower (p = 0.001) with 64- compared to 16-slice CT. The standard deviation of the HU measurements inside the stents was significantly (p = 0.002) lower with 64- than with 16-slice CT. Artifacts outside the stents were not significantly different between the scanners (p = 0.866). Conclusion: Visualization of the in-stent lumen is improved with 64-slice CT when compared with 16-slice CT as quantified by significantly lesser intraluminal image noise and less artificial rise in intraluminal HU measurement, which is the most important parameter for the evaluation of stent patency in vivo

  16. [Computed tomography of the heart

    DEFF Research Database (Denmark)

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

    2009-01-01

    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 th...

  17. Computed tomography of the prostate.

    Science.gov (United States)

    Van Engelshoven, J M; Kreel, L

    1979-02-01

    The conventional anatomy of the prostate is reviewed and the computed tomography (CT) anatomy described and illustrated. The results of 55 "normal" cases were analyzed for size and relationship to the symphysis pubis, retropubic space, and bladder, as shown on CT sections correlating the features with age and possible urinary symptoms. Attention is also drawn to the differences between phleboliths and prostatic calcification. Computed tomography is an effective method of demonstrating the prostate and surrounding structures and of assessing prostatic enlargement.

  18. What is Computed Tomography?

    Science.gov (United States)

    ... word "tomography" is from the Greek word "tomos" meaning "slice" or "section" and "graphe" meaning "drawing." A CT imaging system produces cross-sectional ... The patient may receive an injection of a "contrast material" to facilitate visualization of vascular structure. Detectors ...

  19. Left anterior descending coronary artery myocardial bridging by multislice computed tomography: Correlation with clinical findings

    Energy Technology Data Exchange (ETDEWEB)

    Jodocy, Daniel; Aglan, Iman [Clinical Department of Radiology II, Innsbruck Medical University, Innsbruck (Austria); Friedrich, Guy [Clinical Department of Cardiology, Innsbruck Medical University, Innsbruck (Austria); Mallouhi, Ammar [Clinical Department of Radiology II, Innsbruck Medical University, Innsbruck (Austria); Pachinger, Otmar [Clinical Department of Radiology II, Innsbruck Medical University, Innsbruck (Austria); Clinical Department of Cardiology, Innsbruck Medical University, Innsbruck (Austria); Jaschke, Werner [Clinical Department of Radiology II, Innsbruck Medical University, Innsbruck (Austria); Feuchtner, Gudrun M. [Clinical Department of Radiology II, Innsbruck Medical University, Innsbruck (Austria)], E-mail: gudrun.feuchtner@i-med.ac.at

    2010-01-15

    Objective: To assess the relationship between left anterior descending (LAD) coronary artery myocardial bridging detected by 64-slice computed tomography (CT) and clinical findings. Methods: 221 consecutive patients were examined with coronary 64-slice CT angiography. 21 patients with coronary stenosis >50% were excluded. The length, depth, and luminal narrowing of LAD myocardial bridges during systole and diastole were measured. CT findings were compared with the treadmill ECG-stress test, and clinical symptoms. Results: Myocardial bridges of the LAD were found in 23% of patients (51/221) (length, 14.9 {+-} 6.5 mm; depth, 2.6 {+-} 1.6 mm). A significant difference was noted between the LAD luminal diameter before the intramyocardial course and intramyocardially, for both diastole and systole (p < 0.001); with a higher diameter reduction of 27% for end-systole compared to end-diastole with 15% (p = 0.006). Systolic LAD intramyocardial luminal narrowing >50% was found in 3/25 (8%). 30/51 (59%) of bridges were 'deep' (>2 mm myocardial depth), 21/51 (41%) were 'superficial'. The prevalence of a positive ECG-stress tests for the anterior myocardial region was significantly higher in patients with LAD myocardial bridges (34/50; 68%) compared to those without (28/144; 19.4%) (p < 0.001). There was no difference between 'superficial' and 'deep' LAD myocardial bridges in regard to a positive treadmill ECG-stress test. Typical angina was rare with 6%. Conclusion: LAD myocardial bridges are common findings and can possibly explain a positive exercise ECG-stress test for anterior myocardial ischemia. Intramyocardial LAD segments show mild-to-moderate luminal narrowing at rest, which is higher during end-systolic phase.

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

    Directory of Open Access Journals (Sweden)

    Jie HU

    2010-05-01

    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.

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

    LENUS (Irish Health Repository)

    Killeen, Ronan P

    2012-02-01

    To assess the contractility of accessory left atrial appendages (LAAs) using multiphasic cardiac CT. We retrospectively analyzed the presence, location, size and contractile properties of accessory LAAs using multiphasic cardiac 64-slice CT in 102 consecutive patients (63 males, 39 females, mean age 57). Multiplanar reformats were used to create image planes in axial oblique, sagittal oblique and coronal oblique planes. For all appendages with an orifice diameter >or= 10 mm, axial and sagittal diameters and appendage volumes were recorded in atrial diastole and systole. Regression analysis was performed to assess which imaging appearances best predicted accessory appendage contractility. Twenty-three (23%) patients demonstrated an accessory LAA, all identified along the anterior LA wall. Dimensions for axial oblique (AOD) and sagittal oblique (SOD) diameters and sagittal oblique length (SOL) were 6.3-19, 3.4-20 and 5-21 mm, respectively. All appendages (>or=10 mm) demonstrated significant contraction during atrial systole (greatest diameter reduction was AOD [3.8 mm, 27%]). Significant correlations were noted between AOD-contraction and AOD (R = 0.57, P < 0.05) and SOD-contraction and AOD, SOD and SOL (R = 0.6, P < 0.05). Mean diverticulum volume in atrial diastole was 468.4 +\\/- 493 mm(3) and in systole was 171.2 +\\/- 122 mm(3), indicating a mean change in volume of 297.2 +\\/- 390 mm(3), P < 0.0001. Stepwise multiple regression analysis revealed SOL to be the strongest independent predictor of appendage contractility (R(2) = 0.86, P < 0.0001) followed by SOD (R(2) = 0.91, P < 0.0001). Accessory LAAs show significant contractile properties on cardiac CT. Those accessory LAAs with a large sagittal height or depth should be evaluated for contractile properties, and if present should be examined for ectopic activity during electrophysiological studies.

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

    Energy Technology Data Exchange (ETDEWEB)

    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: plkhong@hkucc.hku.hk [Department of Diagnostic Radiology, University of Hong Kong (Hong Kong)

    2010-11-15

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

    International Nuclear Information System (INIS)

    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

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

    Energy Technology Data Exchange (ETDEWEB)

    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)

    1997-04-01

    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.

  5. Neuroanatomy of cranial computed tomography

    International Nuclear Information System (INIS)

    Based on the fundamental structures visualized by means of computed tomography, the authors present the functional systems which are relevant in neurology by means of axial cross-sections. All drawings were prepared from original preparations by means of a new technique which is similar to the grey values of X-ray CT and nuclear magnetic resonance tomography. A detailed description is given of the topics of neurofunctional lesions

  6. Computed Tomography (CT) -- Sinuses

    Medline Plus

    Full Text Available ... images. These images can be viewed on a computer monitor, printed on film or transferred to a ... other in a ring, called a gantry. The computer workstation that processes the imaging information is located ...

  7. Computed Tomography (CT) -- Head

    Medline Plus

    Full Text Available ... images. These images can be viewed on a computer monitor, printed on film or transferred to a ... other in a ring, called a gantry. The computer workstation that processes the imaging information is located ...

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

    LENUS (Irish Health Repository)

    Martos, R

    2012-02-01

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

  9. Computer tomography in acute pyelonephritis

    Energy Technology Data Exchange (ETDEWEB)

    Triller, J.; Scheidegger, J.; Terrier, F.

    1983-07-01

    Computer tomography of the kidneys was performed on 30 patients with acute renal infections (acute suppurative pyelonephritis, acute renal abscess, infected cyst, pyelonephrosis, calculus perforation, retroperitoneal abscess). Computer tomography provided more accurate information concerning the extent of the renal and extra-renal inflammatory process than did the urogram or sonogram. This may significantly affect the choice of treatment, particularly concerning the use of drugs or of surgery. Angiography and retrograde pyelography may be used in selected cases, especially where there is a suspicion of acute bacterial nephritis, renal vein thrombosis or ureteric obstruction.

  10. The comparative study of 64-slices spiral CT angiography with DSA in lower extremity arterial occlusive diseases

    International Nuclear Information System (INIS)

    Objective: To study the clinical value of 64-slices spiral CTA with DSA comparatively in diagnosis of lower extremity arterial occlusive diseases. Methods: 31 patients with lower extremity arterial occlusive diseases underwent 64-slice spiral CT angiography of lower extremity arteries and they also underwent digital subtraction angiography (DSA)two weeks later. Reconstruction by maximum intensity projection (MIP), volume render (VR)and multiplanar reformatting (MPR)in working-station was undertaken comparing with the bolus chase DSA and traditional DSA for diagnostic accuracy. Results: The 216 arterial segments of lower extremity were selected, including 157 segments with consistent results in demonstrating degree of stenosis by both examinations. On CT angiography, 5 segmental stenosis were overestimated and 9 were underestimated. When stenosis of detected segments is more than 50%, the sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of CTA were 98.21%, 96.15%, 97.22%, 96.49%, and 98.04%, respectively. Conclusion: 64-slices spiral CT angiography is an effective and reliable method for evaluating the lower extremity arterial occlusive diseases and may provide precious information for planning interventional therapy. (authors)

  11. Computed Tomography (CT) -- Sinuses

    Medline Plus

    Full Text Available ... ray beam follows a spiral path. A special computer program processes this large volume of data to create two-dimensional cross-sectional images of your body, which are then displayed on a ... by computer software, the result is a very detailed multidimensional ...

  12. Computed Tomography (CT) -- Head

    Medline Plus

    Full Text Available ... ray beam follows a spiral path. A special computer program processes this large volume of data to create two-dimensional cross-sectional images of your body, which are then displayed on a ... by computer software, the result is a very detailed multidimensional ...

  13. 64-Slice CT Angiography in the Detection of Intracranial Aneurysms: Comparison with DSA and Surgical Findings.

    Science.gov (United States)

    Milošević Medenica, S; V Vućković, V; Prstojević, B

    2010-03-01

    The overall results of CT angiography on 64-slice MSCT published in the last five years are very close to results of DSA which is still a gold standard in the diagnosis of intracranial aneurysms. The aim of this study is to contribute to the confidence in reliability of this method and to try to answer the question of whether CTA should be used as the first diagnostic modality in patients with suspect intracranial aneurysms. In the period from October 2008 to August 2009 we diagnosed 118 aneurysms in 73 patients. We included in this study only those patients who underwent either DSA, surgical treatment or both after MSCTA, and the remainder of the above patients were not treated and are followed up, or died before treatment. So our group comprised 47 patients who were divided into two groups. The first group of 22 patients underwent DSA after MSCTA. We found 36 aneurysms in this group. One aneurysm was falsely positive compared to DSA, while 35 were in concordance with DSA. DSA revealed five aneurysms smaller than 4 mm not disclosed by MSCTA. The second group comprised 25 patients who were operated according to MSCTA findings only. There were 33 aneurysms in this group: 25 aneurysms were operated and surgical findings agreed with MSCTA. Eight aneurysms smaller than 4 mm were not operated and we do not have confirmation for them. In all false positive and false negative cases the misdiagnosed aneurysms were in fact 1-1.5 mm outpouchings that were not responsible for SAH. According to the available literature and our results, MSCTA has proved a very reliable method, simple and safe, competent to be used as a diagnostic modality of choice in the patients with SAH or suspect unruptured aneurysm. DSA should be used in cases of negative or uncertain findings on MSCTA, excluding cases of perimesencephalic SAH with negative MSCTA. The relative disadvantage of this method is its lower sensitivity in the detection of tiny outpouchings, especially in the infraclionid region

  14. Computed Tomography (CT) -- Sinuses

    Medline Plus

    Full Text Available ... special computer program processes this large volume of data to create two-dimensional cross-sectional images of ... Society of Urogenital Radiology note that the available data suggest that it is safe to continue breastfeeding ...

  15. Computed Tomography (CT) -- Head

    Medline Plus

    Full Text Available ... special computer program processes this large volume of data to create two-dimensional cross-sectional images of ... Society of Urogenital Radiology note that the available data suggest that it is safe to continue breastfeeding ...

  16. Computed Tomography (CT) -- Sinuses

    Medline Plus

    Full Text Available ... be viewed on a computer monitor, printed on film or transferred to a CD or DVD. CT ... distinguished from one another on an x-ray film or CT electronic image. In a conventional x- ...

  17. Computed Tomography (CT) -- Head

    Medline Plus

    Full Text Available ... be viewed on a computer monitor, printed on film or transferred to a CD or DVD. CT ... distinguished from one another on an x-ray film or CT electronic image. In a conventional x- ...

  18. Computed Tomography (CT) -- Head

    Medline Plus

    Full Text Available ... look like? The CT scanner is typically a large, box-like machine with a hole, or short ... spiral path. A special computer program processes this large volume of data to create two-dimensional cross- ...

  19. Computed Tomography (CT) -- Sinuses

    Medline Plus

    Full Text Available ... look like? The CT scanner is typically a large, box-like machine with a hole, or short ... spiral path. A special computer program processes this large volume of data to create two-dimensional cross- ...

  20. Computed tomography:the details.

    Energy Technology Data Exchange (ETDEWEB)

    Doerry, Armin Walter

    2007-07-01

    Computed Tomography (CT) is a well established technique, particularly in medical imaging, but also applied in Synthetic Aperture Radar (SAR) imaging. Basic CT imaging via back-projection is treated in many texts, but often with insufficient detail to appreciate subtleties such as the role of non-uniform sampling densities. Herein are given some details often neglected in many texts.

  1. Facility for positron computed tomography

    International Nuclear Information System (INIS)

    The positron computed tomography facility has got scintillator detector rings simultaneously recording more than one tomogrphic image of different cross-sections of the patient. The detectors in neighboring rings are staggered and can be rotated with respect to each other in order to increase the count rate without loss of efficiency. (DG)

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

    Directory of Open Access Journals (Sweden)

    Xi Yang

    2015-04-01

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

    Directory of Open Access Journals (Sweden)

    Irmina Sefić Pašić

    2015-08-01

    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

  4. Computed Tomography (CT) -- Head

    Medline Plus

    Full Text Available ... other medical conditions and whether you have a history of heart disease, asthma, diabetes, kidney disease or ... gantry. The computer workstation that processes the imaging information is located ... in detector technology allow nearly all CT scanners to obtain multiple ...

  5. Computed Tomography (CT) -- Sinuses

    Medline Plus

    Full Text Available ... other medical conditions and whether you have a history of heart disease, asthma, diabetes, kidney disease or ... gantry. The computer workstation that processes the imaging information is located ... in detector technology allow nearly all CT scanners to obtain multiple ...

  6. Optimization of individualized abdominal scan protocol with 64-slice CT scanner

    International Nuclear Information System (INIS)

    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. mAs and 207 eff. mAs were applied respectively in the first and second abdominal scan. The imaging qualities of the two scans were evaluated retrospectively by 3 reviewers. All the individual variants,including height, weight, body mass index (BMI), the maximum transverse diameter, the anteroposterior diameter and the average maximum diameter of abdomen were recorded. A five-point scale was used for grading the image noise of eight organs, including abdominal aorta, portal vein, liver, spleen, gallbladder, pancreas, renal cortex and renal medulla. Diagnostic acceptability of CT images at three anatomic levels,including porta hepatis, pancreas and the upper pole of renal, was also evaluated by using a five-point scale. The noise value of abdominal aorta was defined as the standard deviation (SD) of CT values of aorta at the level of porta hepatis. Scatter diagram and Pearson correlation analysis were used for evaluating the linear relationship between the individual variants and the noise value of abdominal aorta, and multivariate linear regression analysis was used for evaluating the relevance between the individual variants and the noise value of aorta. Results: In this patients group, the average height was (164.6 ± 7.5) cm,the average weight was (64.3 ± 11.0) kg, the BMI was (23.7 ±3.3) kg/m2, the maximum transverse diameter of abdomen was (29.8 ± 2.3) cm, the anteroposterior diameter of abdomen was (23.1 ± 2.9) cm, and the average maximum diameter of abdomen was (26.5 ± 2.5) cm. Pearson correlation analysis showed significant positive linear correlation between the noise value of abdominal aorta (1 1.7 ± 3.0) and patients' weight (r=0

  7. Pediatric cranial computed tomography

    International Nuclear Information System (INIS)

    The introduction of CT in the investigation of intercranial pathology has revolutionized the approach to clinical neurological and neurosurgical practice. This book applies the advances of cranial CT to the pediatric patient. The test is divided into two sections. The first portion describes the practical methodology, anatomy and normal and abnormal CT scan appearance, including high or low density lesions, cystic lesions and ventricular or subarachnoid space dilation. The characteristic scans for various neurological diseases are presented and discussed. The author has given special attention to the CT diagnosis of congenital malformations and cerebral neoplasms. Partial Contents: Normal Computed Tomographic Anatomy/ High Density Lesions/Low Density Lesions/Cystic Lesions; Supratentorial/Cystic Lesions; Infratentorial/Increased Head Circumference/Increased Ventricular Size/Small Ventricular Size/Cranial Lesions/Spinal Lesions/CT Cisternography/Part II CT in Neonates/Congenital Craniocerebral Malformations/Hydrocephalus/Craniosynostosis/Head Trauma/Cerebrovascular Lesions/Intracranial Lesions/Seizure Disorders/Intracranial and Other Chronic Neurological Disorders

  8. Computed tomography of gynecologic diseases

    International Nuclear Information System (INIS)

    Although computed tomography (CT) provides superb images of all areas of the body, sonography, because of its lack of ionizing radiation and its real-time and multiplanar capacities, has become the preferred initial method of evaluating the female pelvis. This has resulted in a relative paucity of information in the literature concerning CT features of benign pelvic disorders in particular and prompted the authors to review our experience with third-generation CT scanning of the uterus and ovaries

  9. Cranial computed tomography in paediatrics

    International Nuclear Information System (INIS)

    This paper deals mainly with methodical aspects (such as sedation, intravenous and intrathecal application of contrast media) and with common difficulties in interpretation of computed tomography images. The indications for cranial CT are discussed in respect probable therapeutic consequences and expected diagnostic yield. In view of the author CT is, as a rule, not required in assessing chronic headache, generalised epileptic convulsions, non-specific mental retardation and cerebral palsy. (Author)

  10. Cranial computed tomography in pediatrics

    Energy Technology Data Exchange (ETDEWEB)

    Boltshauser, E. (Zuerich Univ. (Switzerland). Kinderklinik)

    1984-01-01

    This paper deals mainly with methodical aspects (such as sedation, intravenous and intrathecal application of contrast media) and with common difficulties in interpretation of computed tomography images. The indications for cranial CT are discussed in respect to probable therapeutic consequences and expected diagnostic yield. In the view of the author CT is, as a rule, not required in assessing chronic headache, generalised epileptic convulsions, non-specific mental retardation and cerebral palsy.

  11. Italian multicenter, prospective study to evaluate the negative predictive value of 16- and 64-slice MDCT imaging in patients scheduled for coronary angiography (NIMISCAD-non invasive multicenter Italian study for coronary artery disease)

    Energy Technology Data Exchange (ETDEWEB)

    Marano, Riccardo [Hospital - Catholic University, Department of Bioimaging and Radiological Sciences, Institute of Radiology, Rome (Italy); Cobelli, Francesco de; Maschio, Alessandro del [Vita-Salute Univ., Milan (Italy). Scientifi Inst.; Floriani, Irene [Mario Negri Inst., Milan (Italy); Becker, Christoph [Muenchen Univ. (Germany); Herzog, Christopher [Frankfurt Univ. (Germany); Centonze, Maurizio [Chiara Hospital, Trento (Italy); Morana, Giovanni [Foncello Hospital, Trevisio (Italy); Gualdi, Gian Franco [DEA Umberto Hospital, Rome UNiv. (Italy); Ligabue, Guido [Univ. of Modena (Italy); Pontone, Gianluca [Centro Cardiologico Monzino, Milan (Italy); Catalano, Carlo [Umberto Hospital, La Sapienza Univ., Rome (Italy); Chiappino, Dante [Pasquinucci Hospital, Massa (Italy); Midiri, Massimo [DIBIMEL, Univ. of Palermo (Italy); Simonetti, Giovanni [Tor Vergata Univ., Rome (Italy); Marchisio, Filippo [Univ. of Turin (Italy); Olivetti, Lucio [Istituti Ospitalieri of Cremona (Italy); Fattori, Rossella [Orsola University Hospital, Bologna (Italy); Bonomo, Lorenzo [Gemelli Hospital, Catholic Univ., Rome (Italy)

    2009-05-15

    This was a prospective, multicenter study designed to evaluate the utility of MDCT in the diagnosis of coronary artery disease (CAD) in patients scheduled for elective coronary angiography (CA) using different MDCT systems from different manufacturers. Twenty national sites prospectively enrolled 367 patients between July 2004 and June 2006. Computed tomography (CT) was performed using a standardized/optimized scan protocol for each type of MDCT system ({>=}16 slices) and compared with quantitative CA performed within 2 weeks of MDCT. A total of 284 patients (81%) were studied by 16-slice MDCT systems, while 66 patients (19%) by 64-slice MDCT scanners. The primary analysis was on-site/off-site evaluation of the negative predictive value (NPV) on a per-patient basis. Secondary analyses included on-site evaluation on a per-artery and per-segment basis. On-site evaluation included 327 patients (CAD prevalence 58%). NPV, positive predictive value (PPV), sensitivity, specificity, and diagnostic accuracy (DA) were 0.91 (95% CI 0.85-0.95), 0.91 (95% CI 0.86-0.95), 0.94 (95% CI 0.89-0.97), 0.88 (95% CI 0.81-0.93), and 0.91 (95% CI 0.88-0.94), respectively. Off-site analysis included 295 patients (CAD prevalence 56%). NPV, PPV, sensitivity, specificity, and DA were 0.73 (95% CI 0.65-0.79), 0.93 (95% CI 0.87-0.97), 0.73 (95% CI 0.65-0.79), 0.93 (95% CI 0.87-0.97), and 0.82 (95% CI 0.77-0.86), respectively. The results of this study demonstrate the utility of MDCT in excluding significant CAD even when conducted by centers with varying degrees of expertise and using different MDCT machines. (orig.)

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

    Energy Technology Data Exchange (ETDEWEB)

    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)

    2006-10-15

    The purpose of this study was to evaluate image quality of low-dose electrocardiogram (ECG)-gated multislice helical computed tomography (CT) angiograms of the chest. One hundred and five consecutive patients with a regular sinus rhythm (72 men; 33 women) underwent ECG-gated CT angiographic examination of the chest without administration of beta blockers using the following parameters: (a) collimation 32 x 0.6 mm with z-flying focal spot for the acquisition of 64 overlapping 0.6-mm slices, rotation time 0.33 s, pitch 0.3; (b) 120 kV, 200 mAs; (c) use of two dose modulation systems, including adjustment of the mAs setting to the patient's size and anatomical shape and an ECG-controlled tube current. Subjective and objective image quality was evaluated by two radiologists in consensus on 3-mm-thick scans reconstructed at 55% of the response rate (RR) interval. The population and protocol characteristics included: (a) a mean [{+-}standard deviation (SD)] body mass index (BMI) of 24.47 ({+-}4.64); (b) a mean ({+-}SD) heart rate of 72.04 ({+-}15.76) bpm; (c) a mean ({+-}SD) scanning time of 18.3 ({+-}2.73) s; (d) a mean ({+-}SD) dose-length product (DLP) value of 260.57 ({+-}83.67) mGy/cm; (e) an estimated average effective dose of 4.95 ({+-}1.59) mSv. Subjective noise was depicted in a total of nine examinations (8.5%), always rated as mild. Objective noise was assessed by measuring the standard deviation of pixel values in a homogeneous region of interest within the trachea and descending aorta; SD was 15.91 HU in the trachea and 22.16 HU in the descending aorta, with no significant difference in the mean value of the standard deviations between the four categories of BMI except for obese patients, who had a higher mean SD within the aorta. Interpolation artefacts were depicted in 22 patients, with a mean heart rate significantly lower than that of patients without interpolation artifacts, rated as mild in 11 patients and severe in 11 patients. The severity of

  13. Prognostic value of computed tomography coronary angiography in patients with suspected coronary artery disease: a 24-month follow-up study

    Energy Technology Data Exchange (ETDEWEB)

    Aldrovandi, Annachiara; Maffei, Erica; Seitun, Sara; Martini, Chiara; Ruffini, Livia; Crisi, Girolamo; Ardissino, Diego [Azienda Ospedaliero-Universitaria, Department of Radiology and Cardiology, Parma (Italy); Palumbo, Alessandro [Azienda Ospedaliero-Universitaria, Department of Radiology and Cardiology, Parma (Italy); Erasmus Medical Center, Department of Radiology and Cardiology, Rotterdam (Netherlands); Brambilla, Valerio [University of Parma, Cardiovascular Prevention and Rehabilitation Unit, Don Gnocchi ONLUS, Parma (Italy); Zuccarelli, Alessandra [Ospedale di Carrara, Department of Cardiology, Carrara (Italy); Tarantini, Giuseppe [University of Padua, Department of Cardiology, Padua (Italy); Weustink, Annick C.; Mollet, Nico R.; Feyter, Pim J. de; Krestin, Gabriel P. [Erasmus Medical Center, Department of Radiology and Cardiology, Rotterdam (Netherlands); Cademartiri, Filippo [Azienda Ospedaliero-Universitaria, Department of Radiology and Cardiology, Parma (Italy); Erasmus Medical Center, Department of Radiology and Cardiology, Rotterdam (Netherlands); Azienda Ospedaliero-Universitaria di Parma, Department of Radiology, c/o Piastra Tecnica - Piano 0 - CT Section, Parma (Italy)

    2009-07-15

    The aim of this study was to determine the predictive value of 64-slice computed tomography coronary angiography (CTCA) for major cardiac events in patients with suspected coronary artery disease (CAD). A total of 187 consecutive patients (119 men, age 62.5 {+-} 10.5 years) without known heart disease underwent single-source 64-slice CTCA (Somatom Sensation 64, Siemens) for clinical suspicion of CAD. Patients underwent follow-up for the occurrence of cardiac death, nonfatal myocardial infarction, unstable angina and cardiac revascularization. In total, 2,822 coronary segments were assessed. Forty-two segments (1.5%) were not assessable because of insufficient image quality. Overall, CTCA revealed absence of CAD in 65 (34.7%) patients, nonobstructive CAD (coronary plaque {<=}50%) in 87 (46.5%) patients and obstructive CAD (>50%) in 35 (18.8%) patients. A total of 20 major cardiac events (3 myocardial infarctions, 16 cardiac revascularizations, 1 unstable angina) occurred during a mean follow-up of 24 months. One noncardiac death occurred. Seventeen events occurred in the group of patients with obstructive CAD and three events occurred in the group of nonobstructive CAD. The event rate was 0% among patients with normal coronary arteries at CTCA. CTCA has a 100% negative predictive value for major cardiac events at 24-month follow-up in patients with normal coronary arteries. (orig.)

  14. Single Photon Emission Computed Tomography (SPECT)

    Science.gov (United States)

    ... Tools & Resources Stroke More Single Photon Emission Computed Tomography (SPECT) Updated:Sep 11,2015 What is a ... Heart Attack Myocardial Perfusion Imaging (MPI) Positron Emission Tomography (PET) Radionuclide Ventriculography, Radionuclide Angiography, MUGA Scan Heart ...

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

    Science.gov (United States)

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

  16. Coronary artery imaging with 64-slice CT in atrial fibrillation patients: scanning method and post-processing techniques

    International Nuclear Information System (INIS)

    Objective: To discuss the clinical value of coronary artery imaging using 64-slice CT in patient with atrial fibrillation. Methods: All the cardiac volume data of 31 patients with atrial fibrillation were reconstructed using absolute time method. The images of 12 patients. The images of 31 patients who undeiwent contrast-enhanced CT coronary angiography were evaluated. The presence of stenosis on each segment of coronary arteries was recorded and their degree of stenosis was measured using the vessel analysis software.. The results of conventional coronary angiography (CAG) of the 10 patients were compared with CT coronary angiography. Results: The image quality of 364 coronary vessel segments on the images from 31 patients was evaluated and defined as excellent, fine, moderate or poor. The image quality was excellent, fine, moderate and poor in 194(53.3%), 82(22.5%), 41(11.3%) and 47(12.9%) vessel segments. Comparison was carried out between CTA findings and CAG findings of the 125 segments of the coronary arteries in the 10 patients who underwent CAG. The sensitivity and specificity of CTA for diagnosing vessel with stenosis (≥ 50% narrowing) was 85%(17/20) and 95.2% (100/105). Conclusion: Coronary artery imaging using 64-slice CT is useful in patient with atrial fibrillation. (authors)

  17. The history of computed tomography

    International Nuclear Information System (INIS)

    New scientific discoveries are often made by the synthetising of other discoveries. Computed tomography is such an example. The three necessary elements were: 1/ the fact that certain simple crystals scintillate when exposed to X-rays, 2/ the advent of electronics and 3/ that of computers. The fact that X-rays cause crystals to scintillate was learnt very shortly after Roentgen's discovery, electronics and computers coming very much later. To put all these together and apply them to diagnostic radiology, and at the same time dismiss the concept so firmly ingrained in everyone's mind that an X-ray picture must be produced on photographic film, required a genius. (orig./VJ)

  18. Industrial applications of computed tomography

    DEFF Research Database (Denmark)

    De Chiffre, Leonardo; Carmignato, S.; Kruth, J. -P.;

    2014-01-01

    The number of industrial applications of Computed Tomography(CT) is large and rapidly increasing. After a brief market overview, the paper gives a survey of state of the art and upcoming CT technologies, covering types of CT systems, scanning capabilities, and technological advances. The paper...... contains a survey of application examples from the manufacturing industry as well as from other industries, e.g., electrical and electronic devices, inhomogeneous materials, and from the food industry. Challenges as well as major national and international coordinated activities in the field of industrial...

  19. Facility for positron computed tomography

    International Nuclear Information System (INIS)

    For positron computed tomography two or more rings of scintillation detectors are used by which three or more sections of the object may be determined at a time. The rings are placed in parallel planes having got some distance from each other, axially movable collimator rings being provided for. Each collimator can be moved towards the opposite collimator and towards a central collimator which also is ring-shaped and is placed between the rows of detectors. The external and internal collimator are used for data selection and image-forming. (DG)

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

    Energy Technology Data Exchange (ETDEWEB)

    Buss, Sebastian J., E-mail: sebastian.buss@med.uni-heidelberg.de [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)

    2014-03-15

    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

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

    Science.gov (United States)

    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

  2. Computed tomography of the spine

    International Nuclear Information System (INIS)

    Until the advent of Computed Tomography (CT), axial studies of the spine were limited in the main to gross bony anatomy and to conventional transaxial tomography (TAT). Others studied the upper cervical cord in transverse section during gas myelography and encephalography. The potential role of CT in the evaluation of spinal anatomy and disease was recognized, however, at an early stage in the development of the general purpose CT scanner. CT is not organ specific and therefore provides a uniformly thin (1.5-13 mm) axial section displaying detailed spinal topographical anatomy against a background of paravertebral muscles, vascular structures and body cavity organs. The relationships of the apophyseal joints to the spinal canal and intervertebral foramina are particularly well displayed. The study of neural tissue and pathology within the spinal canal is facilitated by the use of a non-ionic water-soluble contrast medium (viz. metrizamide) in the subarachnoid spaces. The high sensitivity of CT to very small changes in X-ray attenuation permits studies to be continued over several hours. The digital derivation of the sequential CT transaxial sections enables not only interrogation of data and quantitative studies to be made but also makes possible computer-generated reconstructions in other planes

  3. Adaptive Computed Tomography Imaging Spectrometer Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The present proposal describes the development of an adaptive Computed Tomography Imaging Spectrometer (CTIS), or "Snapshot" spectrometer which can...

  4. Evaluation of radiation dose in facial bones and paranasal sinuses examination using computed tomography

    International Nuclear Information System (INIS)

    CT has become an established examination in the evaluation of the paranasal sinuses. CT is a diagnostic imaging modality giving higher patient dose in comparison with other radiological procedures, so the evaluation of organ dose in CT exams is very important. This study intends the measurement of patient dose in computed tomography in facial bones, estimate the organ equivalent dose and related risks to critical organs (eye lens, thyroid, parathyroid gland and pituitary gland. Two multi slice CT scanner (MSCT) 64 slice (Toshiba sensation aquilion 64) and (Siemens sensation 16 slice) were used in this study. All quality control tests were carried out for the two machines by expert from Sudan Atomic Energy Commission (SAEC) prior to data collection. Data were collected in regard to exposure parameter in CT procedures performed for 80 adult patients of age ranging from 20 to 90 years. The effective dose in Alamal Hospital was (22.6±8.9) (mSv) for facial bones and for PNS was (10.05±5.94) (mSv) and the effective dose in Ribat University Hospital was (7.87±6.79) mSv for facial bones, and for PNS was (6.00±2.87) mSv. Patient dose rate received in Alamal Hospital was higher than in the other hospital, this result could be due to increasing number of photons and number of slices. The patients doses in two hospitals were higher than the doses in previous studies. (Author)

  5. Quantitative assessment of left ventricular systolic wall thickening using multidetector computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Kristensen, Thomas S. [Department of Radiology, Diagnostic Centre, Rigshospitalet, University of Copenhagen, Blegdamsvej 9, 2100 Copenhagen (Denmark)], E-mail: tskaarup@yahoo.com; Kofoed, Klaus F. [Department of Cardiology, The Heart Centre, Rigshospitalet, University of Copenhagen, Blegdamsvej 9, 2100 Copenhagen (Denmark)], E-mail: kkofoed@dadlnet.dk; Moller, Daniel V. [Department of Cardiology, Heart Centre, Rigshospitalet, University of Copenhagen, Blegdamsvej 9, 2100 Copenhagen (Denmark)], E-mail: DVEGA@gmx.net; Ersboll, Mads [Department of Cardiology, Heart Centre, Rigshospitalet, University of Copenhagen, Blegdamsvej 9, 2100 Copenhagen (Denmark)], E-mail: ersboell@stud.ku.dk; Kuehl, Tobias [Department of Cardiology, The Heart Centre, Rigshospitalet, University of Copenhagen, Blegdamsvej 9, 2100 Copenhagen (Denmark)], E-mail: tobiaskh@gmail.com; Recke, Peter von der [Department of Radiology, Diagnostic Centre, Rigshospitalet, University of Copenhagen, Blegdamsvej 9, 2100 Copenhagen (Denmark)], E-mail: peter.von.der.recke@rh.regionh.dk; Kober, Lars [Department of Cardiology, Heart Centre, Rigshospitalet, University of Copenhagen, Blegdamsvej 9, 2100 Copenhagen (Denmark)], E-mail: lk@heart.dk; Nielsen, Michael B. [Department of Radiology, Diagnostic Centre, Rigshospitalet, University of Copenhagen, Blegdamsvej 9, 2100 Copenhagen (Denmark)], E-mail: mbn@dadlnet.dk; Kelbaek, Henning [Department of Cardiology, Heart Centre, Rigshospitalet, University of Copenhagen, Blegdamsvej 9, 2100 Copenhagen (Denmark)], E-mail: henning.kelbaek@rh.regionh.dk

    2009-10-15

    Background: Multidetector computed tomography (MDCT) of the heart provides both anatomical and functional information. The objective of this study was to evaluate the accuracy of quantitative assessment of left ventricular contractile function in relation to two-dimensional transthoracic echocardiography (TTE). Materials and methods: Sixty-four patients with known or suspected coronary artery disease underwent ECG-gated 64-slice MDCT and TTE. Regional left ventricular contractile function was measured by percent systolic wall thickening (SWT) in 16 myocardial segments using MDCT, and compared with visual evaluation of wall motion score (WMS) by TTE. Global SWT by MDCT was calculated as the mean SWT of all myocardial segments and compared with wall motion index (WMI) by TTE. Results: Eight hundred and eleven segments (81%) were classified as normokinetic, 142 (14%) as hypokinetic, 41 (4%) as akinetic and 5 (0.5%) as dyskinetic by TTE. A significant inverse linear trend was found between regional SWT by MDCT and WMS by TTE (p < 0.001). Sensitivity and specificity for the identification of regional abnormalities of contractile function were 76% and 78%, respectively. A linear correlation between global SWT by MDCT and WMI by TTE was found (r = -0.8, p < 0.001). Sensitivity and specificity for the identification of WMI > 1.5 using global SWT was 91% and 94%, respectively. Conclusion: Quantification of systolic wall thickening by MDCT provides functional information, which is well correlated to visual assessment of global left ventricular contractile function by TTE.

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

    Institute of Scientific and Technical Information of China (English)

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

    2013-01-01

    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.

  7. Noninvasive coronary angioscopy using electron beam computed tomography and multidetector computed tomography

    NARCIS (Netherlands)

    van Ooijen, PMA; Nieman, K; de Feyter, PJ; Oudkerk, M

    2002-01-01

    With the advent of noninvasive coronary imaging techniques like multidetector computed tomography and electron beam computed tomography, new representation methods such as intracoronary visualization. have been introduced. We explore the possibilities of these novel visualization techniques and comp

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2007-03-15

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

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

    Energy Technology Data Exchange (ETDEWEB)

    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: z.sun@curtin.edu.au; 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)

    2010-04-15

    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.

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

    Energy Technology Data Exchange (ETDEWEB)

    Agid, R.; Lee, S.K.; Willinsky, R.A.; Farb, R.I.; TerBrugge, K.G. [Toronto Western Hospital, Division of Neuroradiology, Department of Medical Imaging, Toronto, Ontario (Canada)

    2006-11-15

    To evaluate the clinical role of CT angiography (CTA) in patients with acute subarachnoid hemorrhage (SAH) for treatment decision-making. Consecutive patients with acute SAH had CTA using a 64-slice scanner for initial clinical decision-making. Image processing included multiplanar volume reformatted (MPVR) maximum intensity projections (MIP) and 3D volume-rendered reconstructions. CTAs were used for (1) evaluating the cause of SAH, and (2) triaging aneurysm-bearing patients to the more appropriate management, either surgical clipping or endovascular coiling. CTA findings were confirmed by neurosurgical exploration or catheter angiography (digital subtraction angiography, DSA). Successful coiling provided evidence that triaging to endovascular treatment was correct. Included in the study were 73 patients. CTA findings were confirmed by DSA or neurosurgical operation in 65 patients, and of these 65, 47 had aneurysmal SAH, 3 had vasculitis, 1 had arterial dissection and 14 had no underlying arterial abnormality. The cause of SAH was detected with CTA in 62 out of the 65 patients (95.4%, sensitivity 94%, specificity 100%). CTA revealed the aneurysm in 46 of 47 patients (98%, sensitivity 98%, specificity 100%, positive predictive value 100%, negative predictive value 82.3%), 1 of 3 vasculitides and 1 of 1 dissection. Of the 46 patients with aneurysm, 44 (95.7%) were referred for treatment based on CTA. In 2 patients (2 of 46, 4.4%) CTA was not informative enough to choose treatment requiring DSA. Of the 44 patients, 27 (61.4%) were referred to endovascular treatment and successful coiling was achieved in 25 (25 of 27, 92.6%). CTA using a 64-slice scanner is an accurate tool for detecting and characterizing aneurysms in acute SAH. CTA is useful in the decision process whether to coil or clip an aneurysm. (orig.)

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

    International Nuclear Information System (INIS)

    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.

  12. 64-multislice detector computed tomography coronary angiography as potential alternative to conventional coronary angiography: a systematic review and meta-analysis

    DEFF Research Database (Denmark)

    Abdulla, Jawdat; Abildstrøm, Steen Zabell; Gøtzsche, Ole;

    2007-01-01

    AIMS: To evaluate the diagnostic accuracy of 64-slice multi-detector computed tomography coronary angiography (64-SCTA) compared with the standard reference conventional coronary angiography (CCA). METHODS AND RESULTS: Based on a systematic search, 27 studies including 1740 patients were eligible...... coronary artery stenosis in per-segment (19 studies) and per-patients (13 studies) populations were 19 and 57.5% respectively. Accuracy tests with 95% confidence intervals comparing 64-SCTA vs. CCA showed that sensitivity, specificity, positive predictive and negative predictive values for native coronary......% by overall per-segment analysis. CONCLUSION: The high diagnostic accuracy of 64-SCTA validates this non-invasive technique as a potential alternative to CCA in carefully selected populations suspected for coronary stenosis....

  13. Computed tomography in sport injuries

    International Nuclear Information System (INIS)

    Computed tomography (CT) provides axial slices plane and shows excellent details of bones and different soft tissues, favoring its use in traumatic lesions caused by sporting activities. Complex anatomical structures such as the shoulder, the vertebral column, the pelvis, the knee, the tarsal and carpal bones are often better recognized in detail than by conventional radiography. Fracture lines, localization of bone fragments and involvement of soft tissues are clearly demonstrated. Luxations and bone changes leading to luxations can be shown. CT arthrography provides for the first time a direct visualization of joint cartilage and of cruciate ligaments in the knee joint, so traumatic lesions such as chondropathia patellae or rupture of the cruciate ligaments are shown with a high degree of reliability. (orig.)

  14. COMPUTED TOMOGRAPHY PERITONEAL CANCER INDEX

    Directory of Open Access Journals (Sweden)

    Tiutiuca RC

    2006-07-01

    Full Text Available Peritoneal surface malignancy results from seeding of gastrointestinal cancer or abdomino-pelvic sarcoma, or it can occur as a primary disease, such as peritoneal mesothelioma. In the past, this clinical situation was treated only with palliative intent. Actual treatment options for surgical management uses cytoreductive surgery which combines peritonectomy and visceral resection in an effort to remove all visible cancer within the abdomen and pelvis. Then the peritoneal cavity is flooded with chemotherapy solution. To select patients for this agressive approach quantitative prognostic indicators for carcinomatosis must be evaluated. The peritoneal cancer index (PCI is a synthesis of the distribution of tumor and a lesion size score. In such conditions abdominal medium contrast computed-tomography it is very helpful in identification of neoplasic implants.

  15. [Computer tomography of sports injuries].

    Science.gov (United States)

    Reiser, M; Rupp, N

    1984-01-01

    Computed tomography (CT) provides axial slices plane and shows excellent details of bones and different soft tissues, favoring its use in traumatic lesions caused by sporting activities. Complex anatomical structures such as the shoulder, the vertebral column, the pelvis, the knee, the tarsal and carpal bones are often better recognized in detail than by conventional radiography. Fracture lines, localization of bone fragments and involvement of soft tissues are clearly demonstrated. Luxations and bone changes leading to luxations can be shown. CT arthrography provides for the first time a direct visualization of joint cartilage and of cruciate ligaments in the knee joint, so traumatic lesions such as chondropathia patellae or rupture of the cruciate ligaments are shown with a high degree of reliability.

  16. Computed tomography in sport injuries

    Energy Technology Data Exchange (ETDEWEB)

    Reiser, M.; Rupp, N.

    1984-01-01

    Computed tomography (CT) provides axial slices plane and shows excellent details of bones and different soft tissues, favoring its use in traumatic lesions caused by sporting activities. Complex anatomical structures such as the shoulder, the vertebral column, the pelvis, the knee, the tarsal and carpal bones are often better recognized in detail than by conventional radiography. Fracture lines, localization of bone fragments and involvement of soft tissues are clearly demonstrated. Luxations and bone changes leading to luxations can be shown. CT arthrography provides for the first time a direct visualization of joint cartilage and of cruciate ligaments in the knee joint, so traumatic lesions such as chondropathia patellae or rupture of the cruciate ligaments are shown with a high degree of reliability.

  17. Diagnostic usefulness of computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Suzuki, K.; Tsugawa, R.; Yamakawa, Y. (Kanazawa Medical Univ., Uchinada, Ishikawa (Japan))

    1981-07-01

    Computed tomography (CT) has been used as a diagnostic technique in various urological diseases. Here demonstrated is a case of ureteral incontinence with double renal pelvis whose upper one has ectopic ureteral orifice. Also a case of ureteral stricture in transplanted kidney and three cases of uric acid calculi are demonstrated. CT provides accurate information in each diagnostic procedure. The use of CT in the diagnosis of urinary stones is estimated. CT number of 75 stones with single component shows specific distribution in relation to the component; ex. calcium stones: 900 - 1000, cystine: 700 - 800, struvite: 600 - 700, uric acid: 400 - 500. Structure and component of the stone is easily demonstrated by CT, especially about nonopaque calculi, whose image is positively displayed only by CT.

  18. Computed tomography in hepatic trauma

    International Nuclear Information System (INIS)

    Twenty-five patients with hepatic injury from blunt upper abdominal trauma were examined by computed tomography (CT). The spectrum of CT findings was recorded, and the size of the hepatic laceration and the associated hemoperitoneum were correlated with the mode of therapy used in each case (operative vs nonoperative). While the need for surgery correlated roughly with the size of the hepatic laceration, the size of the associated hemoperitoneum was an important modifying factor. Fifteen patients with hepatic lacerations but little or no hemoperitoneum were managed nonoperatively. CT seems to have significant advantages over hepatic scintigraphy, angiography, and diagnostic peritoneal lavage. By combining inforamtion on the clinical state of the patient and CT findings, therapy of hepatic injury can be individualized and the incidence of nontherapeutic laparotomies decreased

  19. Computed tomography of cryogenic cells

    Energy Technology Data Exchange (ETDEWEB)

    Schneider, Gerd; Anderson, E.; Vogt, S.; Knochel, C.; Weiss, D.; LeGros, M.; Larabell, C.

    2001-08-30

    Due to the short wavelengths of X-rays and low numerical aperture of the Fresnel zone plates used as X-ray objectives, the depth of field is several microns. Within the focal depth, imaging a thick specimen is to a good approximation equivalent to projecting the specimen absorption. Therefore, computed tomography based on a tilt series of X-ray microscopic images can be used to reconstruct the local linear absorption coefficient and image the three-dimensional specimen structure. To preserve the structural integrity of biological objects during image acquisition, microscopy is performed at cryogenic temperatures. Tomography based on X-ray microscopic images was applied to study the distribution of male specific lethal 1 (MSL-1), a nuclear protein involved in dosage compensation in Drosophila melanogaster, which ensures that males with single X chromosome have the same amount of most X-linked gene products as females with two X chromosomes. Tomographic reconstructions of X-ray microscopic images were used to compute the local three-dimensional linear absorption coefficient revealing the arrangement of internal structures of Drosophila melanogaster cells. Combined with labelling techniques, nanotomography is a new technique to study the 3D distribution of selected proteins inside whole cells. We want to improve this technique with respect to resolution and specimen preparation. The resolution in the reconstruction can be significantly improved by reducing the angular step size to collect more viewing angles, which requires an automated data acquisition. In addition, fast-freezing with liquid ethane instead of cryogenic He gas will be applied to improve the vitrification of the hydrated samples. We also plan to apply cryo X-ray nanotomography in order to study different types of cells and their nuclear protein distributions.

  20. The Western Denmark Cardiac Computed Tomography Registry

    DEFF Research Database (Denmark)

    Nielsen, Lene Hüche; Nørgaard, Bjarne Linde; Tilsted, Hans Henrik;

    2015-01-01

    BACKGROUND: As a subregistry to the Western Denmark Heart Registry (WDHR), the Western Denmark Cardiac Computed Tomography Registry (WDHR-CCTR) is a clinical database established in 2008 to monitor and improve the quality of cardiac computed tomography (CT) in Western Denmark. OBJECTIVE: We...

  1. [Computed tomography and cranial paleoanthropology].

    Science.gov (United States)

    Cabanis, Emmanuel Alain; Badawi-Fayad, Jackie; Iba-Zizen, Marie-Thérèse; Istoc, Adrian; de Lumley, Henry; de Lumley, Marie-Antoinette; Coppens, Yves

    2007-06-01

    Since its invention in 1972, computed tomography (C.T.) has significantly evolved. With the advent of multi-slice detectors (500 times more sensitive than conventional radiography) and high-powered computer programs, medical applications have also improved. CT is now contributing to paleoanthropological research. Its non-destructive nature is the biggest advantage for studying fossil skulls. The second advantage is the possibility of image analysis, storage, and transmission. Potential disadvantages include the possible loss of files and the need to keep up with rapid technological advances. Our experience since the late 1970s, and a recent PhD thesis, led us to describe routine applications of this method. The main contributions of CT to cranial paleoanthropology are five-fold: --Numerical anatomy with rapid acquisition and high spatial resolution (helicoidal and multidetector CT) offering digital storage and stereolithography (3D printing). --Numerical biometry (2D and 3D) can be used to create "normograms" such as the 3D craniofacial reference model used in maxillofacial surgery. --Numerical analysis offers thorough characterization of the specimen and its state of conservation and/or restoration. --From "surrealism" to virtual imaging, anatomical structures can be reconstructed, providing access to hidden or dangerous zones. --The time dimension (4D imaging) confers movement and the possibility for endoscopic simulation and internal navigation (see Iconography). New technical developments will focus on data processing and networking. It remains our duty to deal respectfully with human fossils. PMID:18402165

  2. Odontogenic Inflammatory Processes of Head and Neck in Computed Tomography Examinations

    International Nuclear Information System (INIS)

    Infections of odontogenic origin are the most common cause of inflammatory disease of head and neck region. Computed tomography allows for defining localization and extent of inflammatory lesions, visualizes soft tissue involvement, presence of an abscess or an osteolytic lesion around causative tooth. The aim of this study was to assess pathways, by which odontogenic infections spread into respective deep head and neck structures in computed tomography examination, taking into account the following criteria: frequency of involvement of respective deep cervical spaces, possibility to determine a probable causative tooth and concordance with the results of clinical examination. Thirty-eight patients cervicofacial inflammatory disease had undergone CT examination of head and neck region with a 64-slice CT scanner after intravenous contrast administration. Abscess was reported in 30 (79%) cases, while inflammatory infiltration was diagnosed in remaining 8 (21%) patients. There was full concordance between radiological report and intraoperative report In 33 cases (87%). The most commonly involved cervical space was masticator space – 31 patients (82%), followed by submandibular space – 27 patients (71%). Dental examination was impossible in 29 patient because of trismus. During analysis of CT studies we evaluated maxillary and mandibular alveolar processes for presence of osteolytic bone lesions around causative teeth roots and we found them in 30 cases (79%). In 32 cases (84%) cervicofacial infection were of mandibular odontogenic origin. In most cases CT study in patients suspected of odontogenic craniofacial infection revealed presence of an abscess, needing urgent surgery. Inflammatory infiltration of dental origin most frequently involves masticator space, followed by submandibular space. In most cases CT scanning allows for identification of causative teeth, especially when trismus makes detailed clinical examination impossible

  3. Computer simulations to estimate organ doses from clinically validated cardiac, neuro, and pediatric protocols for multiple detector computed tomography scanners

    Science.gov (United States)

    Ghita, Monica

    Recent advances in Computed Tomography (CT) technology, particularly that of multiple detector CT (MDCT) scanning, have provided increased utilization and more diverse clinical applications including more advanced vascular and cardiac exams, perfusion imaging, and screening exams. Notwithstanding the benefits to the patient undergoing a CT study, the fundamental concern in radiation protection is the minimization of the radiation exposure delivered as well as the implementation of structures to prevent inappropriate ordering and clinical use of these advanced studies. This research work developed a computational methodology for routine clinical use to assess patient organ doses from MDCT scanners. To support the methodology, a computer code (DXS-Diagnostic X-ray Spectra) was developed to accurately and conveniently generate x-ray spectra in the diagnostic energy range (45-140 keV). The two accepted standard radiation transport calculation methods namely, deterministic and Monte Carlo, have been preliminarily investigated for their capability and readiness to support the proposed goal of the work. Thorough tests demonstrated that the lack of appropriate discrete photon interaction coefficients in the aforementioned diagnostic energy range impedes the applicability of the deterministic approach to routine clinical use; improvements in the multigroup treatment may make it more viable. Thus, the open source Monte Carlo code, MCNP5, was adapted to appropriately model an MDCT scan. For this, a new method, entirely based on routine clinical CT measurements, was developed and validated to generate an "equivalent source and filtration" model that obviates the need of proprietary information for a given CT scanner. Computer simulations employing the Monte Carlo methodology and UF's tomographic human phantoms were performed to assess, compare, and optimize pediatric, cardiac and neuro-imaging protocols for the new 320-slice scanner at Shands/UF based on dose considerations

  4. Computed tomography and three-dimensional imaging

    International Nuclear Information System (INIS)

    Presented here is a brief introduction to two-, three-, and four-dimensional computed tomography. More detailed descriptions of the mathematics of reconstruction and of CT scanner operation are presented elsewhere. The complementary tomographic imaging methods of single-photon-emission tomography (SPECT) positron-emission tomography (PET), nuclear magnetic resonance (NMR) imaging, ulltrasound sector scanning, and ulltrasound computer-assisted tomography [UCAT] are only named here. Each imaging modality ''probes'' the body with a different energy form, yielding unique and useful information about tomographic sections through the body

  5. Fracture of the orbit: computed tomography appearance

    International Nuclear Information System (INIS)

    The main mechanisms of orbital fractures and their clinical symptoms are exposed. The computed tomographic appearance is described and the implication of computed tomography for therapeutic indications is evaluated as a function of clinical symptoms: visual impairment, anomaly of pupillary reaction to light, ophthalmoplegia, exophthalmos and associated injuries such as intracranial hematomas. The role of computed tomography for the follow-up of these patients is considered

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2006-09-15

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

  7. Computed tomography of the kidney

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Young Kyun; Lee, Sun Wha; Kim, Soon Yong [Kyung Hee University Hospital, Seoul (Korea, Republic of)

    1980-12-15

    It is generally accepted that the computed tomography is an extremely accurate means to obtain more definite information on the diagnosis of renal masses, although the conventional excretory urography remains the primary tool in the diagnosis of renal disorders. The authors studied 62 cases of proven renal disorders among 758 abdominal CT scans performed during the period from Oct. 1977 to Jan. 1980 in Kyung Hee University Hospital. The results were as follows: 1. Of 23 simple renal cyst cases, 20 cases were found incidentally and 17 of them were over 50 years of age. 2. The CT scan have proved to be an extremely accurate means in differentiating benign renal cyst from neoplastic origin; based on attenuation value, demarcation from normal renal parenchyme and thickness of wall, especially the attenuation value. 3. CT scan holds great promise in diagnosing renal tumors, especially in staging of tumor and determining surgical feasibility and its approach. 4. Pathology and its extension of retroperitoneal space was demonstrated accurately by CT and cause of nonfunctioning kidney could be often explained without retrograde pyelography. 5. Associated polycystic changes in liver, spleen and pancreas to polycystic kidney was easily diagnosed by CT alone.

  8. X-ray computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Kalender, Willi A [Institute of Medical Physics, University Erlangen-Nuernberg, Henkestr. 91, D-91052 Erlangen (Germany)

    2006-07-07

    X-ray computed tomography (CT), introduced into clinical practice in 1972, was the first of the modern slice-imaging modalities. To reconstruct images mathematically from measured data and to display and to archive them in digital form was a novelty then and is commonplace today. CT has shown a steady upward trend with respect to technology, performance and clinical use independent of predictions and expert assessments which forecast in the 1980s that it would be completely replaced by magnetic resonance imaging. CT not only survived but exhibited a true renaissance due to the introduction of spiral scanning which meant the transition from slice-by-slice imaging to true volume imaging. Complemented by the introduction of array detector technology in the 1990s, CT today allows imaging of whole organs or the whole body in 5 to 20 s with sub-millimetre isotropic resolution. This review of CT will proceed in chronological order focussing on technology, image quality and clinical applications. In its final part it will also briefly allude to novel uses of CT such as dual-source CT, C-arm flat-panel-detector CT and micro-CT. At present CT possibly exhibits a higher innovation rate than ever before. In consequence the topical and most recent developments will receive the greatest attention. (review)

  9. Computed tomography in abnormalities of the hip

    Energy Technology Data Exchange (ETDEWEB)

    Visser, J.D.; Jonkers, A.; Klasen, H.J. (Rijksuniversiteit Groningen (Netherlands). Academisch Ziekenhuis); Hillen, B. (Rijksuniversiteit Groningen (Netherlands). Lab. voor Anatomie en Embryologie)

    1982-06-26

    The value of computed tomography in the assessment of abnormalities of the hip is demonstrated with the aid of an anatomical preparation and in patients with, respectively, congenital dislocation of a hip, dislocation of the hip in spina bifida, an acetabular fracture and a Ewing tumour. The anteversion of the acetabulum and femur and the instability index of the hip joint can be measured by means of computed tomography.

  10. Quantitative computed tomography evaluation of pulmonary disease

    DEFF Research Database (Denmark)

    McEvoy, Fintan; Buelund, Lene Elisabeth; Strathe, Anders Bjerring;

    2009-01-01

    Objective assessment of pulmonary disease from computed tomography (CT) examinations is desirable but difficult. When such assessments can be made, it is important that they are related to some part of the pathophysiologic process present.......Objective assessment of pulmonary disease from computed tomography (CT) examinations is desirable but difficult. When such assessments can be made, it is important that they are related to some part of the pathophysiologic process present....

  11. Computed tomography in abnormalities of the hip

    International Nuclear Information System (INIS)

    The value of computed tomography in the assessment of abnormalities of the hip is demonstrated with the aid of an anatomical preparation and in patients with, respectively, congenital dislocation of a hip, dislocation of the hip in spina bifida, an acetabular fracture and a Ewing tumour. The anteversion of the acetabulum and femur and the instability index of the hip join can be measured by means of computed tomography. (Auth.)

  12. Examination of weld defects by computed tomography

    Directory of Open Access Journals (Sweden)

    M. Jovanović

    2012-04-01

    Full Text Available Defects in metal arc gas (MAG welds made in S235JR low carbon steel of 6 mm thickness were examined. A sample containing lack of fusion (LOF and pores was examined by computed tomography – CT. The computed tomography examination was performed in order to define LOF size and position as well as dimensions and distribution of accompanying pores in the weld metal.

  13. Preliminary study of X-ray dosage reduction using post-processing filter in 64-slice spiral CT cardiac examination

    International Nuclear Information System (INIS)

    Objective: To evaluate the adaptive post-processing filter (C2) on reducing X-ray dosage in 64-slice CT cardiac examinations. Methods: The study was divided into two steps: (1) On 30 consecutive patients (group A) prescribed for cardiac scans on 64-slice CT, the scan protocol was 120 kV, 640 mA, 0.35 s/r, 0.625 mm slice thickness, 0.22-0.24 pitch and large body bowtie. For each patients, cardiac images were reconstructed with and without C2 filter to create two image sets (C2 and NC2, respectively). The image quality was blindly evaluated between C2 and NC2. Image noises were also measured and their means and standard deviations calculated for the two sets. Statistical t-test analysis was performed on the quality scores and the noise between the two data sets. (2) On the 30 consecutive cardiac patients in another group (group B), the protocol was kept the same as in group A except for decreasing the tube current 450 mA based on the results from group A. Images were reconstructed using post-processing filter C2 to create 2C2 image set. Statistical t-test was performed between image sets of 2C2 and NC2 in step 1. (3) CTDIvol values from the 2C2 and NC2 (C2) groups were converted into effective dose (ED) and the ED values of the two groups were compared. Results: (1) The image quality scores for the C2 and NC2 sets were 3.71±0.31 and 3.72±0.29, respectively, with t-test of P>0.05, indicating no significant statistical difference (P>0.05). The noise of C2 and NC2 sets were 22±4, 27±5, respectively, indicating the difference was statistically significant (P2 filter had 18% noise reduction compared to those without C2 filter. (2) The image quality scores for the 2C2 and NC2 sets were 3.67± 0.34, 3.72±0.29, indicating no significant statistical difference (P>0.05). The noise of 2C2 and NC2 sets were 26±3, 27±5, indicating no significant statistical difference (P>0.05). (3) The average CTDIvol values were 60±5 mGy, 88±10 mGy for 2C2 and NC2 (C2) groups

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

    International Nuclear Information System (INIS)

    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.)

  15. Assessments of Coronary Artery Visibility and Radiation Dose in Infants with Congenital Heart Disease on Cardiac 128-slice CT and on Cardiac 64-slice CT.

    Science.gov (United States)

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

    2016-01-01

    The aim of this study was to compare the coronary artery visibility and radiation dose in infants with CHD on cardiac 128-slice CT and on cardiac 64-slice CT. The images of 200 patients were analyzed in this study, 100 patients were selected randomly from a group of 789 infants (ECG-triggered axial scan, and 100 were selected randomly from 911 infants with CHD undergoing 64-slice CT retrospective ECG-gated spiral scan. The visibility of coronary artery segments was graded on a four-point scale. The coronary arteries were considered to be detected or visible when grade was 2 or higher. The visibility of the coronary artery segments and the radiation dose was compared between the two groups. Except for the rate of LM (96 vs. 99%), the detection rates of the total, LAD, LCX, RCA, and the proximal segment of the RCA in the 256-slice CT group were significantly higher than those in the 64-slice CT group (51.7, 53.33, 33.67, 53.33, and 99 vs. 34.8, 34.33, 18, 30.67, and 75%, respectively). The counts of visibility score (4/3/2/1) for the LM and the proximal segment of the RCA were 62/22/12/4 and 56/20/17/7, respectively, in the 128-slice CT group and 17/42/30/1 and 9/30/38/25, respectively, in the 64-slice CT group. There were significant differences, especially for score 4 and 3, between the two groups. The radiation dose in the 128-slice CT group was significantly decreased than those in the 64-slice CT group (CTDIvol 1.88 ± 0.51 vs. 5.61 ± 0.63 mGy; SSDE 4.48 ± 1.15 vs. 13.97 ± 1.52 mGy; effective radiation dose 1.36 ± 0.44 vs. 4.06 ± 0.7 mSv). With reduced radiation dose, the visibility of the coronary artery in infants with CHD via prospective ECG-triggered mode on a 128-slice CT is superior to that of the 64-slice CT using retrospective ECG-gated spiral mode. PMID:26271472

  16. 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

    Institute of Scientific and Technical Information of China (English)

    马建华; 张华; 边兆英; 李双学; 赵大哲; 陈武凡

    2015-01-01

    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.

  17. Contrast-enhanced coronary artery visualization by dual-source computed tomography-Initial experience

    International Nuclear Information System (INIS)

    Multi-detector computed tomography (CT) scanners, by virtue of their high temporal and spatial resolution, permit imaging of the coronary arteries. However, motion artifacts, especially in patients with higher heart rates, can impair image quality. We thus evaluated the performance of a new dual-source CT (DSCT) with a heart rate independent temporal resolution of 83 ms for the visualization of the coronary arteries in 14 consecutive patients. Methods: Fourteen patients (mean age 61 years, mean heart rate 71 min-1) were studied by DSCT. The system combines two arrays of an X-ray tube plus detector (64 slices) mounted on a single gantry at an angle of 90o With a rotation speed of 330 ms, a temporal resolution of 83 ms (one-quarter rotation) can be achieved independent of heart rate. For data acquisition, intraveous contrast agent was injected at a rate of 5 ml/s. Images were reconstructed with 0.75 slice thickness and 0.5 mm increment. The data sets were evaluated concerning visibility of the coronary arteries and occurrence of motion artifact. Results: Visualization of the coronary arteries was successful in all patients. Most frequently, image reconstruction at 70% of the cardiac cycle provided for optimal image quality (50% of patients). Of a total of 226 coronary artery segments, 222 (98%) were visualized free of motion artifact. In summary, DSCT constitutes a promising new concept for cardiac CT. High and heart rate independent temporal resolution permits imaging of the coronary arteries without motion artifacts in a substantially increased number of patients as compared to earlier scanner generations. Larger and appropriately designed studies will need to determine the method's accuracy for detection of coronary artery stenoses

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

    Energy Technology Data Exchange (ETDEWEB)

    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)

    2014-10-15

    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.)

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

    Directory of Open Access Journals (Sweden)

    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.

  20. Contrast-enhanced coronary artery visualization by dual-source computed tomography-Initial experience

    Energy Technology Data Exchange (ETDEWEB)

    Achenbach, Stephan [Department of Cardiology, University of Erlangen-Nuernberg, Ulmenweg 18, 91054 Erlangen (Germany) and Department of Radiology, Massachusetts General Hospital, Boston, MA (United States)]. E-mail: stephan.achenbach@med2.med.uni-erlangen.de; Ropers, Dieter [Department of Cardiology, University of Erlangen-Nuernberg, Ulmenweg 18, 91054 Erlangen (Germany); Kuettner, Axel [Institute for Diagnostic Radiology, University of Erlangen-Nuernberg, Erlangen (Germany); Flohr, Thomas [Siemens Medical Solutions, Forchheim (Germany); Ohnesorge, Bernd [Siemens Medical Solutions, Forchheim (Germany); Bruder, Herbert [Siemens Medical Solutions, Forchheim (Germany); Theessen, Heike [Siemens Medical Solutions, Forchheim (Germany); Karakaya, Meri [Institute of Medical Physics, University of Erlangen-Nuernberg, Erlangen (Germany); Daniel, Werner G. [Department of Cardiology, University of Erlangen-Nuernberg, Ulmenweg 18, 91054 Erlangen (Germany); Bautz, Werner [Institute for Diagnostic Radiology, University of Erlangen-Nuernberg, Erlangen (Germany); Kalender, Willi A. [Institute of Medical Physics, University of Erlangen-Nuernberg, Erlangen (Germany); Anders, Katharina [Institute for Diagnostic Radiology, University of Erlangen-Nuernberg, Erlangen (Germany)

    2006-03-15

    Multi-detector computed tomography (CT) scanners, by virtue of their high temporal and spatial resolution, permit imaging of the coronary arteries. However, motion artifacts, especially in patients with higher heart rates, can impair image quality. We thus evaluated the performance of a new dual-source CT (DSCT) with a heart rate independent temporal resolution of 83 ms for the visualization of the coronary arteries in 14 consecutive patients. Methods: Fourteen patients (mean age 61 years, mean heart rate 71 min{sup -1}) were studied by DSCT. The system combines two arrays of an X-ray tube plus detector (64 slices) mounted on a single gantry at an angle of 90{sup o} With a rotation speed of 330 ms, a temporal resolution of 83 ms (one-quarter rotation) can be achieved independent of heart rate. For data acquisition, intraveous contrast agent was injected at a rate of 5 ml/s. Images were reconstructed with 0.75 slice thickness and 0.5 mm increment. The data sets were evaluated concerning visibility of the coronary arteries and occurrence of motion artifact. Results: Visualization of the coronary arteries was successful in all patients. Most frequently, image reconstruction at 70% of the cardiac cycle provided for optimal image quality (50% of patients). Of a total of 226 coronary artery segments, 222 (98%) were visualized free of motion artifact. In summary, DSCT constitutes a promising new concept for cardiac CT. High and heart rate independent temporal resolution permits imaging of the coronary arteries without motion artifacts in a substantially increased number of patients as compared to earlier scanner generations. Larger and appropriately designed studies will need to determine the method's accuracy for detection of coronary artery stenoses.

  1. Computer axial tomography in geosciences

    International Nuclear Information System (INIS)

    Computer Axial Tomography (CAT) is one of the most adequate non-invasive techniques for the investigation of the internal structure of a large category of objects. Initially designed for medical investigations, this technique, based on the attenuation of X- or gamma-ray (and in some cases neutrons), generates digital images which map the numerical values of the linear attenuation coefficient of a section or of the entire volume of the investigated sample. Shortly after its application in medicine, CAT has been successfully used in archaeology, life sciences, and geosciences as well as for the industrial materials non-destructive testing. Depending on the energy of the utilized radiation as well as on the effective atomic number of the sample, CAT can provide with a spatial resolution of 0.01 - 0.5 mm, quantitative as well as qualitative information concerning local density, porosity or chemical composition of the sample. At present two types of axial Computer Tomographs (CT) are in use. One category, consisting of medical as well as industrial CT is equipped with X-ray tubes while the other uses isotopic gamma-ray sources. CT provided with intense X-ray sources (equivalent to 12-15 kCi or 450-550 TBq) has the advantage of an extremely short running time (a few seconds and even less) but presents some disadvantages known as beam hardening and absorption edge effects. These effects, intrinsically related to the polychromatic nature of the X-rays generated by classical tubes, need special mathematical or physical corrections. A polychromatic X-ray beam can be made almost monochromatic by means of crystal diffraction or by using adequate multicomponent filters, but these devices are costly and considerably diminish the output of X-ray generators. In the case of CT of the second type, monochromatic gamma-rays generated by radioisotopic sources, such as 169 Yb (50.4 keV), 241 Am (59 keV), 192 Ir (310.5 and 469.1 keV ) or 137 Cs (662.7 keV), are used in combination with

  2. Children's (Pediatric) CT (Computed Tomography)

    Medline Plus

    Full Text Available ... images. These images can be viewed on a computer monitor, printed on film or transferred to a ... a gantry, which rotates around the patient. The computer that processes the imaging information and monitor are ...

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

    Directory of Open Access Journals (Sweden)

    Chen-Pin Chou

    2013-08-01

    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.

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

    Institute of Scientific and Technical Information of China (English)

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

    2010-01-01

    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

  5. Evaluation of laryngeal carcinoma by computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Kwak, Jeong Ho; Kim, Su Mi; Lee, Sun Wha; Eun, Tchung Ki; Kim, Soon Yong [Kyung Hee University Hospital, Seoul (Korea, Republic of)

    1984-09-15

    The limitation of direct or indirect laryngoscopy and laryngogram in determining the exact site and anatomic location of laryngeal carcinoma were well documented by many authors. As compared with laryngoscopy and laryngogram, computed tomographic study for laryngeal cancer is more exact and accurate method demonstrating anatomic sites of involvement, invasion into deep soft tissue spaces of endolarynx, destruction of laryngeal cartilages and cervical metastasis. Fourteen laryngeal cancer patients proven by laryngoscopic biopsy were further examined by computed tomography for staging. The authors compared laryngoscopic findings with those of computed tomography, and their clinical, surgical and computed tomographic findings were analysed. The results were as follows; 1. All patients were proved as squamous cell carcinoma. They were 12 males and 2 females aged over 50 yr. 2. Common clinical symptoms were hoarsense, dysphagia and swallowing difficulty. The primary anatomic sites determined by CT were 8 transglottic, 2 glottic, 2 supraglottic and 1 pyriform sinus respectively. They were 2 T1, 7 T2,1 T3, 3 T4 by TNM systems, respectively. (One case was difficult to evaluate exactly). 3. Invasion into deep soft tissue spaces of endolarynx, cartilage destruction, and neck metastasis were relatively predominant in transglottic carcinomas. 4. Compute tomography was superior in evaluating tumor invasion, especially into deep sift tissue spaces of endolarynx, laryngeal cartilages and metastasis to soft tissue and lymph nodes of neck. However computed tomography had some limitation in determining primary site of laryngeal cancer.

  6. Usefulness of computed tomography in recurrent nephrolithiasis

    International Nuclear Information System (INIS)

    For five cases of recurrent stone formers we performed Computed Tomography, which revealed non-visualized small stones on KUB and uric acid stones. Case 1 was primary hyperparathyroidism. Case 2 had several episodes of spontaneous stone passage without any stone shadow on routine X-ray examination. Case 3 had single ureteral stone on X-ray film. Case 4 had several episodes of spontaneous passage of mixed stones (uric acid and calcium oxalate). Case 5 had bilateral radiolucent large renal stones. We emphasized the superiority of Computed Tomography in search and prophylactic therapy of the stone formation. (author)

  7. Assessments of Coronary Artery Visibility and Radiation Dose in Infants with Congenital Heart Disease on Cardiac 128-slice CT and on Cardiac 64-slice CT.

    Science.gov (United States)

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

    2016-01-01

    The aim of this study was to compare the coronary artery visibility and radiation dose in infants with CHD on cardiac 128-slice CT and on cardiac 64-slice CT. The images of 200 patients were analyzed in this study, 100 patients were selected randomly from a group of 789 infants (coronary artery segments was graded on a four-point scale. The coronary arteries were considered to be detected or visible when grade was 2 or higher. The visibility of the coronary artery segments and the radiation dose was compared between the two groups. Except for the rate of LM (96 vs. 99%), the detection rates of the total, LAD, LCX, RCA, and the proximal segment of the RCA in the 256-slice CT group were significantly higher than those in the 64-slice CT group (51.7, 53.33, 33.67, 53.33, and 99 vs. 34.8, 34.33, 18, 30.67, and 75%, respectively). The counts of visibility score (4/3/2/1) for the LM and the proximal segment of the RCA were 62/22/12/4 and 56/20/17/7, respectively, in the 128-slice CT group and 17/42/30/1 and 9/30/38/25, respectively, in the 64-slice CT group. There were significant differences, especially for score 4 and 3, between the two groups. The radiation dose in the 128-slice CT group was significantly decreased than those in the 64-slice CT group (CTDIvol 1.88 ± 0.51 vs. 5.61 ± 0.63 mGy; SSDE 4.48 ± 1.15 vs. 13.97 ± 1.52 mGy; effective radiation dose 1.36 ± 0.44 vs. 4.06 ± 0.7 mSv). With reduced radiation dose, the visibility of the coronary artery in infants with CHD via prospective ECG-triggered mode on a 128-slice CT is superior to that of the 64-slice CT using retrospective ECG-gated spiral mode.

  8. Children's (Pediatric) CT (Computed Tomography)

    Medline Plus

    Full Text Available ... a gantry, which rotates around the patient. The computer that processes the imaging information and monitor are located in ... ray beam follows a spiral path. A special computer program processes this series of pictures, or slices of the ...

  9. Paradoxical emboli: demonstration using helical computed tomography of the pulmonary artery associated with abdominal computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Delalu, P.; Ferretti, G.R.; Bricault, I.; Ayanian, D.; Coulomb, M. [Service Central de Radiologie et Imagerie Medicale, CHU Grenoble (France)

    2000-02-01

    We report the case of a 60-year-old woman with a recent history of a cerebrovascular accident. Because of clinical suspicion of pulmonary embolism and negative Doppler ultrasound findings of the lower limbs, spiral computed tomography of the pulmonary artery was performed and demonstrated pulmonary emboli. We emphasize the role of computed tomography of the abdomen, performed 3 min after the thoracic acquisition, which showed an unsuspected thrombus within the abdominal aorta and the left renal artery with infarction of the left kidney. Paradoxical embolism was highly suspected on computed tomography data and confirmed by echocardiography which demonstrated a patent foramen ovale. (orig.)

  10. Children's (Pediatric) CT (Computed Tomography)

    Medline Plus

    Full Text Available ... which are then displayed on a monitor. Special software can also generate three-dimensional (3-D) images ... When the image slices are reassembled by computer software, the result is a very detailed multidimensional view ...

  11. Children's (Pediatric) CT (Computed Tomography)

    Medline Plus

    Full Text Available Toggle navigation Test/Treatment Patient Type Screening/Wellness Disease/Condition Safety En Español More Info Images/Videos News Physician Resources Professions Site Index A-Z Children's (Pediatric) CT (Computed ...

  12. Computed Tomography (CT) Perfusion in Abdominal Cancer

    DEFF Research Database (Denmark)

    Hansen, Martin Lundsgaard; Norling, Rikke; Lauridsen, Carsten;

    2013-01-01

    Computed Tomography (CT) Perfusion is an evolving method to visualize perfusion in organs and tissue. With the introduction of multidetector CT scanners, it is now possible to cover up to 16 cm in one rotation, and thereby making it possible to scan entire organs such as the liver with a fixed...

  13. Neutron computed tomography of rat lungs

    International Nuclear Information System (INIS)

    Using conventional methods, three-dimensional imaging of the lung is challenging because of the low contrast between air and tissue and the large differences in dimensions between various pulmonary structures. The small distal airway structures and the high air-to-tissue ratio of lung tissue require an imaging technique which reliably discriminates between air and water. The objective of this study was to assess whether neutron computed tomography would satisfy such a requirement. This method utilizes the unique characteristic of neutrons of directly interacting with the atomic nucleus rather than being scattered by the atomic shell. Neutron computed tomography was tested in rats and allowed differentiation of larger lung structures (e.g., lobes) and distal airways. Airways could be identified reliably down to the sixth bronchial generation, in some cases even down to the tenth generation. The lung could be stabilized for sufficiently long exposure times to achieve an image resolution of 50-60 μm, which is the current physical resolution limit of the neutron computed tomography facility. Neutron computed tomography allowed excellent lung imaging without the need for additional tissue preparation or contrast media. The enhanced structural resolution obtained by applying this new research technique may improve understanding of lung physiology and respiratory therapy. (note)

  14. Cone beam computed tomography in veterinary dentistry

    NARCIS (Netherlands)

    B. van Thielen; F. Siguenza; B. Hassan

    2012-01-01

    The purpose of this study was to assess the feasibility of cone beam computed tomography (CBCT) in imaging dogs and cats for diagnostic dental veterinary applications. CBCT scans of heads of six dogs and two cats were made. Dental panoramic and multi-planar reformatted (MPR) para-sagittal reconstruc

  15. Computed tomography scanning during a traumatic resuscitation

    NARCIS (Netherlands)

    L.F.M. Beenen; R. Adams; R.W. Koster; T. Otto

    2011-01-01

    In cardiopulmonary resuscitation, computed tomography (CT) imaging could be of decisive importance to therapeutic strategy making but is yet unavailable because of incompatibility of CT scanning and manual chest compressions. In this report, we describe a case in which CT scanning was performed on a

  16. Neutron computed tomography of rat lungs

    Energy Technology Data Exchange (ETDEWEB)

    Metzke, R W; Wall, W A [Institute for Computational Mechanics at Technische Universitaet Muenchen, 85747 Garching (Germany); Runck, H; Stahl, C A; Schneider, M; Guttmann, J [Department of Anesthesiology, Section for Experimental Anesthesiology, University Medical Center Freiburg, 79106 Freiburg (Germany); Schillinger, B; Calzada, E; Muehlbauer, M; Schulz, M [Forschungsneutronenquelle Heinz Maier-Leibnitz (FRM-II) and Fakultaet fuer Physik E21 at Technische Universitaet Muenchen, 85748 Garching (Germany); Priebe, H-J, E-mail: metzke@lnm.mw.tum.d [Department of Anesthesiology, University Medical Center Freiburg, 79106 Freiburg (Germany)

    2011-01-07

    Using conventional methods, three-dimensional imaging of the lung is challenging because of the low contrast between air and tissue and the large differences in dimensions between various pulmonary structures. The small distal airway structures and the high air-to-tissue ratio of lung tissue require an imaging technique which reliably discriminates between air and water. The objective of this study was to assess whether neutron computed tomography would satisfy such a requirement. This method utilizes the unique characteristic of neutrons of directly interacting with the atomic nucleus rather than being scattered by the atomic shell. Neutron computed tomography was tested in rats and allowed differentiation of larger lung structures (e.g., lobes) and distal airways. Airways could be identified reliably down to the sixth bronchial generation, in some cases even down to the tenth generation. The lung could be stabilized for sufficiently long exposure times to achieve an image resolution of 50-60 {mu}m, which is the current physical resolution limit of the neutron computed tomography facility. Neutron computed tomography allowed excellent lung imaging without the need for additional tissue preparation or contrast media. The enhanced structural resolution obtained by applying this new research technique may improve understanding of lung physiology and respiratory therapy. (note)

  17. Lung Nodule Detection in Screening Computed Tomography

    CERN Document Server

    Gori, I; Cerello, P; Cheran, S C; De Nunzio, G; Fantacci, M E; Kasae, P; Masala, G L; Pérez-Martínez, A; Retico, A

    2007-01-01

    A computer-aided detection (CAD) system for the identification of pulmonary nodules in low-dose multi-detector helical Computed Tomography (CT) images with 1.25 mm slice thickness is presented. The basic modules of our lung-CAD system, a dot-enhancement filter for nodule candidate selection and a neural classifier for false-positive finding reduction, are described. The results obtained on the collected database of lung CT scans are discussed.

  18. Optimisation of contrast medium volume and injection-related factors in CT pulmonary angiography: 64-slice CT study

    Energy Technology Data Exchange (ETDEWEB)

    Uysal Ramadan, Selma [Ankara Training and Research Hospital, Department of Radiology, Ankara (Turkey); Ankara Training and Research Hospital, Cebeci, Ankara (Turkey); Kosar, Pinar; Sonmez, Iclal; Kosar, Ugur [Ankara Training and Research Hospital, Department of Radiology, Ankara (Turkey); Karahan, Sevilay [Hacettepe University, Department of Biostatistics, Faculty of Medicine, Ankara (Turkey)

    2010-09-15

    To compare the image quality of computed tomography pulmonary angiography (CTPA) obtained with the injection of various low doses of contrast medium (CM) with different injection-related factors. A total of 90 patients (42 females, 48 males; 54.3 {+-} 18.6 years) undergoing CTPA were included. Three CM protocols, each containing 30 patients, were created. Protocols 1, 2 and 3 consisted of a CM of 60 ml, 55 ml and 50 ml, and a bolus trigger level of 120 HU, 90 HU and 75 HU, respectively. Injection was uniphasic for protocols 1 and 2 (flow rate 5 ml/s), and biphasic for protocol 3 (flow rates 5 and 4 ml/s); with saline flushing afterwards. Enhancement was measured in three central and six peripheral pulmonary arteries. The mean attenuation value for pulmonary arteries was over 250 HU for all protocols. There was no difference between the attenuation levels with the protocols (p > 0.05). The percentage of pulmonary arteries exceeding optimal attenuation ({>=}250 HU) showed that protocols 2 and 3 were 90-100% successful (p < 0.05). The use of proper injection-related factors during CTPA, such as a low trigger level and a high flow rate with saline injection following a decreased CM volume (55 ml or 50 ml), will enable adequate pulmonary artery contrast enhancement. (orig.)

  19. Parallel Computing for the Computed-Tomography Imaging Spectrometer

    Science.gov (United States)

    Lee, Seungwon

    2008-01-01

    This software computes the tomographic reconstruction of spatial-spectral data from raw detector images of the Computed-Tomography Imaging Spectrometer (CTIS), which enables transient-level, multi-spectral imaging by capturing spatial and spectral information in a single snapshot.

  20. Computed tomography of tuberculous meningitis

    Energy Technology Data Exchange (ETDEWEB)

    Sato, Noriko; Sato, Hiromi; Kawaguchi, Tetsuro; Fujita, Katsuzo; Tanaka, Makoto (Kobe Univ. (Japan). School of Medicine)

    1982-12-01

    Recently, tuberculous meningitis has become rather rare except in areas where tuberculosis is still endemic. Six adolescents and young adults with tuberculous meningitis were evaluated by means of serial computerized tomography (CT), and the results were correlated with the findings of surgical specimens or autopsies. All cases showed meningeal irritation and fever at onset. CSF cultures revealed the presence of tuberculous bacilli. Four cases advanced rapidly to the clinical stage III and expired in a short period-between two weeks to one month from onset. On initial CT scanning, the disappearance of the basal cistern was a characteristic finding in all these cases. With the progression, an enhancement of the basal cistern on contrast injection, a localized hypodensity in adjacent parenchyma, and symmetrical ventricular dilatation appeared. Two autopsied cases showed tuberculous granulomas with purulent materials, thickened meninges, and caseous necrosis in the parenchyma around the basal cistern. The other two cases progressed rather slowly. CT findings at Stage II showed multiple enhanced spots in the basal subcortical area following contrast injection. Tuberculous granulomas were identified in these parts by means of explorative craniotomy. The authors point out the pathognomonic CT findings of tuberculous meningitis and emphasize the necessity of serial CT for the early detection and management of tuberculous meningitis.

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

    Science.gov (United States)

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

    2016-09-01

    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.

  2. Children's (Pediatric) CT (Computed Tomography)

    Medline Plus

    Full Text Available ... child may have, and if there is a history of heart disease, asthma, diabetes, kidney disease or ... the patient. The computer that processes the imaging information and monitor are ... in detector technology allow new CT scanners to obtain multiple slices ...

  3. Real-time three-dimensional echocardiographic left ventricular ejection fraction and volumes assessment: comparison with cardiac computed tomography

    International Nuclear Information System (INIS)

    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)

  4. Acute pancreatitis: diagnostic value of ultrasonography and computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Blery, M.; Hautefeuille, P.; Jacquenod, P. and others

    1987-09-01

    The value of ultrasonography and computed tomography for the diagnosis, extension, pronostic, complications and etiology of acute pancreatitis is discussed. Ultrasonography and computed tomography guided interventional radiology techniques are valuable in the management of pancreatitis complications such as abscesses.

  5. Acute pancreatitis: diagnostic value of ultrasonography and computed tomography

    International Nuclear Information System (INIS)

    The value of ultrasonography and computed tomography for the diagnosis, extension, pronostic, complications and etiology of acute pancreatitis is discussed. Ultrasonography and computed tomography guided interventional radiology techniques are valuable in the management of pancreatitis complications such as abscesses

  6. Cerebral candidiasis. Computed tomography appearance

    Energy Technology Data Exchange (ETDEWEB)

    Chaabane, M.; Ladeb, M.F.; Bouhaouala, M.H.; Ben Hammouda, M.; Ataalah, R.; Gannouni, A.; Krifa, H.

    1989-07-01

    A three year old child who had been suffering from oral candidiasis since the age of 1 year presented with osteitis of the clavicle, 2 cerebral frontal abscesses and an occipital abscess which extended across the calvaria and was associated with osteolysis. Histological and microbiological studies following surgery confirmed the diagnosis of candidiasis in this girl who was found to have IgA immunodefinciency. The authors report the computed tomographic appearance of the cerebral lesions and review the literature. (orig.).

  7. Cerebral candidiasis. Computed tomography appearance

    International Nuclear Information System (INIS)

    A three year old child who had been suffering from oral candidiasis since the age of 1 year presented with osteitis of the clavicle, 2 cerebral frontal abscesses and an occipital abscess which extended across the calvaria and was associated with osteolysis. Histological and microbiological studies following surgery confirmed the diagnosis of candidiasis in this girl who was found to have IgA immunodefinciency. The authors report the computed tomographic appearance of the cerebral lesions and review the literature. (orig.)

  8. Application of 64-slice spiral computed tomography in measurement of simulated puncture channels of intrahepatic portosystemic shunt%64层螺旋CT在肝内门腔分流模拟穿刺途径测量中的应用

    Institute of Scientific and Technical Information of China (English)

    王剑华; 周庭永; 吕发金; 张琳; 刘本菊; 张本斯; 张志伟

    2009-01-01

    Objective To offer clinical applicable information on morphology by means of measurement of the simulated puncture channel of the right portal branch at 1 and 2 cm and venae hepaticae intermediae and right hepatic veins at 1,2, and 3 cm in patients without liver diseases and those with cirrhosis Child-Pugh grade A and B. Methods Abdominal 64-MSCT scan was performed in 40 cases without liver diseases and 14 cases of cirrhosis after the test of the celiac levels of abdominal aorta was conducted by the smart tracking technology (Smart Prep). The data were processed for imaging on the GE ADW4.2 workstation. Rosults Significant difference was found between the normal group and cirrhosis Child-Pugh grade A and B groups, φMHV1, φRHV1 (P <0.05). The diameter of the normal right hepatic vein at 1-2 cm and that of the middle hepatic vein at 1-2 cm decreased rapidly as compared with that of cirrhosis Child-Pugh grade A and B groups. There was also significant difference (P<0.05) between the normal and cirrhosis Child-Pugh grade A and B groups in the simulated puncture channels of DMHV2-RPV1, DMHV3-RPV1, DMHV3-RPV2, and DRHV1-RPV1. Conclusion 64-MSCT and the three-dimensional reconstruction may be an effective way for accurate measure-ment of the intrinsic liver vessels in vivo. The study of the simulated intrahepatic portosystemic shunt can help to choose the appropriate length and type of the stents.%目的 通过64层螺旋CT(64-MSCT)对非肝病患者及肝硬化Child-Pugh A、B分级组患者门静脉右支1、2 cm处与肝中静脉、肝右静脉1、2、3 cm间模拟穿刺途径进行测量.方法 选取上腹部64-MSCT扫描非肝病被检查组共40例;肝硬化组符合纳入标准14例.用智能追踪技术启动扫描,在GE ADW4.2工作站进行处理.结果 正常组与肝硬化Child-Push A、B分级组φMHV1、φRHV1有统计学差异(P<0.05).正常组肝右静脉1~2 cm处及肝中静脉1~2 cm处直径较肝硬化Child-Pugh A、B分级组减小迅速.正常组与肝硬化Child-Pugh A、B分级组模拟穿刺途径距离DMHV2-RPV1、DMHV3-RPV1、DMHV3-RPV2、DRHV1-RPV1间有统计学差异(P<0.05).结论 64-MSCT及三维重建技术是准确测量活体功能状态下肝内血管的有效方法.肝内门腔分流术模拟穿刺途径的研究有助于选择适当长度和类型的支架.

  9. Relationship between Willis circle variation and the occurrence of anterior and posterior communicaring artery aneurysms investigated by 64-slice CT angiography%CT血管成像评价颅内Willis环变异与前后交通动脉动脉瘤发生的关系

    Institute of Scientific and Technical Information of China (English)

    王洪生; 徐新文; 王辉; 杨昭伟; 王鹏; 赵佩林; 王阳春

    2011-01-01

    目的 探讨大脑前动脉水平段(A1段)发育异常和胚胎型大脑后动脉与颅内前、后交通动脉动脉瘤形成的关系. 方法 回顾性分析216例64排CT血管成像(CTA)的资料.①将216例中CTA发现有前后交通动脉动脉瘤的126例,分为前交通动脉动脉瘤(ACoAA)组69例和后交通动脉动脉瘤(PCoAA)组57例,其余CTA检查无动脉瘤,但有头痛、头晕的90例患者,作为对照组.②分析动脉瘤的有无,动脉瘤的部位、形态、大小和瘤颈的宽度、瘤顶指向及瘤体与周围结构的关系等.③将判定结果与手术结果进行对照.④同时观察大脑前动脉A1段是否存在发育不良或缺如,是否存在胚胎型大脑后动脉. 结果 ①64排CTA共检出前、后交通动脉动脉瘤126例,其中ACoAA 69例,PCoAA57例,以DSA和手术为判断标准,64排CTA检出动脉瘤的敏感性和特异性均为100%.②ACoAA组中一侧A1段发育不良或缺如达81.7%,明显高于PCoAA组和对照组(P <0.05);PCoAA组中胚胎型大脑后动脉达56.1%,明显高于ACoAA组和对照组(P<0.05).结论 (1)64排CTA检出动脉瘤具有较高的敏感性和特异性;②一侧大脑前动脉Al段发育不良或缺如及胚胎型大脑后动脉与前、后交通动脉动脉瘤的发生密切相关.%Objective To investigate the relationship between the dysplasia of horizontal segment ( A1 segment) of anterior cerebral artery and the formation of anterior and posterior communicating artery aneurysms. Methods The data of 64-slice computed tomography angiography (CTA) of 216 patients were analyzed retrospectively. Of the 216 patients, CTA found 126 patients with aneurysm. They were di-vided into anterior communicating artery aneurysm ( ACoAA) group (n =69) and posterior communicating artery aneurysm (PCoAA)group (re =57). The other patients without aneurysm revealed by CTA but with headache and dizziness (n =90) were used as a control group. The presence or absence of aneurysm

  10. Introducing Seismic Tomography with Computational Modeling

    Science.gov (United States)

    Neves, R.; Neves, M. L.; Teodoro, V.

    2011-12-01

    Learning seismic tomography principles and techniques involves advanced physical and computational knowledge. In depth learning of such computational skills is a difficult cognitive process that requires a strong background in physics, mathematics and computer programming. The corresponding learning environments and pedagogic methodologies should then involve sets of computational modelling activities with computer software systems which allow students the possibility to improve their mathematical or programming knowledge and simultaneously focus on the learning of seismic wave propagation and inverse theory. To reduce the level of cognitive opacity associated with mathematical or programming knowledge, several computer modelling systems have already been developed (Neves & Teodoro, 2010). Among such systems, Modellus is particularly well suited to achieve this goal because it is a domain general environment for explorative and expressive modelling with the following main advantages: 1) an easy and intuitive creation of mathematical models using just standard mathematical notation; 2) the simultaneous exploration of images, tables, graphs and object animations; 3) the attribution of mathematical properties expressed in the models to animated objects; and finally 4) the computation and display of mathematical quantities obtained from the analysis of images and graphs. Here we describe virtual simulations and educational exercises which enable students an easy grasp of the fundamental of seismic tomography. The simulations make the lecture more interactive and allow students the possibility to overcome their lack of advanced mathematical or programming knowledge and focus on the learning of seismological concepts and processes taking advantage of basic scientific computation methods and tools.

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

    Institute of Scientific and Technical Information of China (English)

    赵义芹; 祖德贵; 曾庆玉

    2012-01-01

    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.

  12. Practical management of computed tomography

    International Nuclear Information System (INIS)

    For examinations of the spinal canal is used computed myelography as an adjunct to water-soluble conventional myelography. For CT alone about 3.5 g. of metrizamide in isotonic solution is adequate for all investigations. If the constrast medium has to be run into the head by gravity, as in the detection of cerebrospinal fluid fistula or empty sella, or for detailed examination of the basal cisterns, phenobarbitone 100 mg. t.d.s. is commenced on the eve of the examination and continued for 48 hours. A similar dose is also administered to epileptic subject. If fits should occur they are treated with intravenous diazepam and prophylactic phenobarbitone is administered. (orig./AJ)

  13. Cone beam computed tomography in endodontic

    Energy Technology Data Exchange (ETDEWEB)

    Durack, Conor; Patel, Shanon, E-mail: conordurack1@hotmail.com [Unit of Endodontology, Department of Conservative Dentistry, King' s College London, London (United Kingdom)

    2012-07-01

    Cone beam computed tomography (CBCT) is a contemporary, radiological imaging system designed specifically for use on the maxillofacial skeleton. The system overcomes many of the limitations of conventional radiography by producing undistorted, three-dimensional images of the area under examination. These properties make this form of imaging particularly suitable for use in endodontic. The clinician can obtain an enhanced appreciation of the anatomy being assessed, leading to an improvement in the detection of endodontic disease and resulting in more effective treatment planning. In addition, CBCT operates with a significantly lower effective radiation dose when compared with conventional computed tomography (CT). The purpose of this paper is to review the current literature relating to the limitations and potential applications of CBCT in endodontic practice. (author)

  14. Contrast-induced nephropathy after computed tomography

    Directory of Open Access Journals (Sweden)

    Luciano da Silva Selistre

    2015-03-01

    Full Text Available Introduction: Contrast induced nephropathy is the third most prevalent preventable cause of acute kidney injury in hospitalized patients. It defined as an absolute increase in serum creatinine ≥ 0.5 mg/dL and relative ≥ 25% increase. Objective: We studied the risk factors to intravenous injection contrast nephropathy after computed tomography. Methods: We studied 400 patients prospectively. Results: The incidence of contrast induced nephropathy, with an absolute or a relative increase were 4.0% and 13.9%, respectively. Diabetes and cardiac failure were independent risk factors for CIN a relative increase de serum creatinine (O.R.: 3.5 [95% CI: 1.92-6.36], p < 0.01, 2.61 [95% CI: 1.14-6.03%], p < 0.05, respectively. Conclusions: We showed association between uses of intravenous injection contrast after computed tomography with acute injury renal, notably with diabetes and heart failure.

  15. Possibilities of computer tomography in multiple sclerosis

    International Nuclear Information System (INIS)

    Computer tomography was performed in 41 patients with multiple sclerosis, the average age of patients being 40.8 years. Native examinations were made of 17 patients, examinations with contrast medium of 19, both methods were used in the examination of 5 patients. In 26 patients, i.e. in almost two-thirds, cerebral atrophy was found, in 11 of a severe type. In 9 patients atrophy affected only the hemispheres, in 16 also the stem and cerebellum. The stem and cerebellum only were affected in 1 patient. Hypodense foci were found in 21 patients, i.e. more than half of those examined. In 9 there were multiple foci. In most of the 19 examined patients the hypodense changes were in the hemispheres and only in 2 in the cerebellum and brain stem. No hyperdense changes were detected. The value and possibilities are discussed of examinations by computer tomography multiple sclerosis. (author)

  16. Biliary obstruction: Helical computed tomography cholangiography evaluation

    International Nuclear Information System (INIS)

    Helical computed tomography cholangiography (HCTC) takes advantage of the improvement in the quality of multiplanar and three-dimensional reconstructions resulting from the volumetric acquisition of data achieved with helical computed tomography and the indirect opacification of the bile ducts provided by cholangiographic contrast media. This method was used to evaluate 31 patients with suspected biliary obstruction over a one-year period and the findings were compared with those of direct cholangiography and/or surgery. Biliary opacification was sufficient to allow three-dimensional reconstructions in 90,3% of cases. Sensitivity was 81% for the diagnosis of choledochoolithiasis and 100% for ascariasis, choledochal cysts and anatomic variants of the biliary tree. Our results indicate that HCTC is a valuable alternative as a diagnostic method prior to direct cholangiography. Direct cholangiography should be reserved for those patients who require it as part of a therapeutic procedure

  17. [Pneumothorax revealed by postoperative computed tomography].

    Science.gov (United States)

    Ikeda, Shizuka; Katori, Kiyoshi; Fujimoto, Minoru; Nitahara, Keiichi; Higa, Kazuo

    2005-11-01

    We report a case of pneumothorax revealed by postoperative computed tomography. A 39-year-old obese woman (height 153 cm, weight 70 kg) with fractures of the radius, ulna, clavicle, and femur in a traffic accident, was scheduled for osteosynthesis. Anesthesia was induced with thiopental and maintained with 50% nitrous oxide in oxygen and sevoflurane. The Spo2 decreased from 99% to 94% during the surgery. Bilateral chest sounds were symmetrical. The Spo2 increased to 100% after discontinuation of nitrous oxide. Pneumothorax was not evident on a postoperative chest X-ray, but computed tomography of the chest demonstrated right-sided pneumothorax. An ECG electrode had overlapped the fractured rib on the preoperative chest X-ray.

  18. Cone beam computed tomography in endodontic

    International Nuclear Information System (INIS)

    Cone beam computed tomography (CBCT) is a contemporary, radiological imaging system designed specifically for use on the maxillofacial skeleton. The system overcomes many of the limitations of conventional radiography by producing undistorted, three-dimensional images of the area under examination. These properties make this form of imaging particularly suitable for use in endodontic. The clinician can obtain an enhanced appreciation of the anatomy being assessed, leading to an improvement in the detection of endodontic disease and resulting in more effective treatment planning. In addition, CBCT operates with a significantly lower effective radiation dose when compared with conventional computed tomography (CT). The purpose of this paper is to review the current literature relating to the limitations and potential applications of CBCT in endodontic practice. (author)

  19. Computed Tomography of Transverse Phase Space

    Energy Technology Data Exchange (ETDEWEB)

    Watts, A. [Fermilab; Johnstone, C. [Fermilab; Johnstone, J. [Fermilab

    2016-09-19

    Two computed tomography techniques are explored to reconstruct beam transverse phase space using both simulated beam and multi-wire profile data in the Fermilab Muon Test Area ("MTA") beamline. Both Filtered Back-Projection ("FBP") and Simultaneous Algebraic Reconstruction Technique ("SART") algorithms [2] are considered and compared. Errors and artifacts are compared as a function of each algorithm’s free parameters, and it is shown through simulation and MTA beamline profiles that SART is advantageous for reconstructions with limited profile data.

  20. Computed tomography of ancient Egyptian mummies.

    Science.gov (United States)

    Harwood-Nash, D C

    1979-12-01

    This first report of the application of computed tomography (CT) to the study of ancient mummies, the desiccated brain of a boy and the body of a young woman within her cartonnage, shows that CT is uniquely suitable for the study of such antiquities, a study that does not necessitate destruction of the mummy or its cartonnage. Exquisite images result that are of great paleoanatomical, paleopathological, and archeological significance.

  1. Dynamic computed tomography of the brain

    International Nuclear Information System (INIS)

    Dynamic computed tomography (CT) studies of the brain are based on a rapid intravenous bolus injection of radiographic contrast material immediately followed by serial CT scans. The recycling times for this technique are 1 sec or less. Dynamic studies, which are relatively non-invasive, add considerable information to the static cerebral scan as it is presently performed. The resulting time-density patterns are described and typical examples of each are shown. (orig.)

  2. Improvement in computed tomography spatial resolution

    International Nuclear Information System (INIS)

    One of the most important recent developments in transmission computed tomography is the improvement in spatial resolution. Applications of this technical advance to the neuroradiographic exploration of such structures as spinal cord, nerve roots and pituitary gland - as well as the orbits and inner and middle ear - is still limited to a few centers. Increased spatial resolution appears to be an effective means to increase our diagnostic capabilities. The higher dosimetry connected with this modality needs to be emphasized. (orig.)

  3. Encapsulating peritonitis: computed tomography and surgical correlation

    Energy Technology Data Exchange (ETDEWEB)

    Kadow, Juliana Santos; Fingerhut, Carla Jeronimo Peres; Fernandes, Vinicius de Barros; Coradazzi, Klaus Rizk Stuhr; Silva, Lucas Marciel Soares; Penachim, Thiago Jose, E-mail: vinicius.barros.fernandes@gmail.com [Pontificia Universidade Catolica de Campinas (PUC-Campinas), Campinas, SP (Brazil). Hospital e Maternidade Celso Pierro

    2014-07-15

    Sclerosing encapsulating peritonitis is a rare and frequently severe entity characterized by total or partial involvement of small bowel loops by a membrane of fibrous tissue. The disease presents with nonspecific clinical features of intestinal obstruction, requiring precise imaging diagnosis to guide the treatment. The present report emphasizes the importance of computed tomography in the diagnosis of this condition and its confirmation by surgical correlation. (author)

  4. Computed tomography in gastrointestinal stromal tumors

    International Nuclear Information System (INIS)

    The aim of this study was to define the imaging characteristics of primary and recurrent gastrointestinal stromal tumors (GIST) in computed tomography with respect to the tumor size. Computed tomography was performed in 35 patients with histologically confirmed gastrointestinal stromal tumors and analyzed retrospectively by two experienced and independent radiologist. The following morphologic tumor characteristics of primary (n=20) and (n=16) recurrent tumors were evaluated according to tumor size, shape, homogeneity, density compared with liver, contrast enhancement, presence of calcifications, ulcerations, fistula or distant metastases and the anatomical relationship to the intestinal wall, and the infiltration of adjacent visceral organs. Small GIST (5-10 cm) demonstrated an irregular shape, inhomogeneous density on unenhanced and contrast-enhanced images, a combined intra- and extraluminal tumor growth with aggressive findings, and infiltration of adjacent organs in 9 primary diagnosed and 2 recurrent tumors. Large GIST (>10 cm), which were observed in 8 primary tumors and 11 recurrent tumors, showed an irregular margin with inhomogeneous density and aggressive findings, and were characterized by signs of malignancy such as distant and peritoneal metastases. Small recurrent tumors had a similar appearance as compared with large primary tumors. Computed tomography gives additional information with respect to the relationship of gastrointestinal stromal tumor to the gastrointestinal wall and surrounding organs, and it detects distant metastasis. Primary and recurrent GIST demonstrate characteristic CT imaging features which are related to tumor size. Aggressive findings and signs of malignancy are found in larger tumors and in recurrent disease. Computed tomography is useful in detection and characterization of primary and recurrent tumors with regard to tumor growth pattern, tumor size, and varied appearances of gastrointestinal stromal tumors, and indirectly

  5. Computed tomography in gastrointestinal stromal tumors

    Energy Technology Data Exchange (ETDEWEB)

    Ghanem, Nadir; Altehoefer, Carsten; Winterer, Jan; Schaefer, Oliver; Springer, Oliver; Kotter, Elmar; Langer, Mathias [Department of Diagnostic Radiology, University Hospital Freiburg, Hugstetter Strasse 55, 79106, Freiburg (Germany); Furtwaengler, Alex [Department of Abdominal Surgery, University Hospital Freiburg, Hugstetter Strasse 55, 79106, Freiburg (Germany)

    2003-07-01

    The aim of this study was to define the imaging characteristics of primary and recurrent gastrointestinal stromal tumors (GIST) in computed tomography with respect to the tumor size. Computed tomography was performed in 35 patients with histologically confirmed gastrointestinal stromal tumors and analyzed retrospectively by two experienced and independent radiologist. The following morphologic tumor characteristics of primary (n=20) and (n=16) recurrent tumors were evaluated according to tumor size, shape, homogeneity, density compared with liver, contrast enhancement, presence of calcifications, ulcerations, fistula or distant metastases and the anatomical relationship to the intestinal wall, and the infiltration of adjacent visceral organs. Small GIST (<5 cm) showed a sharp tumor margin with homogeneous density and structure on unenhanced and contrast-enhanced images, and were characterized by an intraluminal tumor growth. Intermediate sized GIST (>5-10 cm) demonstrated an irregular shape, inhomogeneous density on unenhanced and contrast-enhanced images, a combined intra- and extraluminal tumor growth with aggressive findings, and infiltration of adjacent organs in 9 primary diagnosed and 2 recurrent tumors. Large GIST (>10 cm), which were observed in 8 primary tumors and 11 recurrent tumors, showed an irregular margin with inhomogeneous density and aggressive findings, and were characterized by signs of malignancy such as distant and peritoneal metastases. Small recurrent tumors had a similar appearance as compared with large primary tumors. Computed tomography gives additional information with respect to the relationship of gastrointestinal stromal tumor to the gastrointestinal wall and surrounding organs, and it detects distant metastasis. Primary and recurrent GIST demonstrate characteristic CT imaging features which are related to tumor size. Aggressive findings and signs of malignancy are found in larger tumors and in recurrent disease. Computed tomography

  6. Analysis of computed tomography of ovarian tumor

    Energy Technology Data Exchange (ETDEWEB)

    Omura, Makoto; Taniike, Keiko; Nishiguchi, Hiroyasu

    1987-07-01

    One hundred and twenty six patients with ovarian mass were studied with computed tomography (CT) and classified into five groups according to its margin and inner structure. The incidence of malignancy of cystic ovarian mass with smooth margin was low and that of solid ovarian mass with irreglar margin was high. Three cases (6.7 %) of malignant ovarian tumor demonstrated completely cystic pattern. Ovarian teratomas contained well defined component of fat density.

  7. HORSESHOE KIDNEY: A MULTIDETECTOR COMPUTED TOMOGRAPHY STUDY

    Directory of Open Access Journals (Sweden)

    Sharma V

    2015-06-01

    Full Text Available Background and Objective: Horseshoe kidney is the most common renal fusion anomaly with a reported prevalence of 1 in 400 persons with a male to female ratio of 2:1. In many cases its presence may go unnoticed and undiagnosed because the patient may remain asymptomatic throughout life. The objective of our study is to report radiological and anatomical features of horseshoe kidney detected incidentally during retrospective evaluation of multidetector computed tomography scans. Materials and Methods: Contrast enhanced multidetector computed tomography scans of 682 patients, 355 males and 327 females, were reviewed retrospectively. Results: Seven cases of horseshoe kidney were detected incidentally, six males and one female, with an incidence of 1.02 %. In all cases, malrotation of the kidneys were observed with the hilum facing anteriorly or anterolaterally. The isthmus was made up of parenchymal tissue in all the cases and the fusion was midline in four cases and lateral in three cases. Horseshoe kidney in all cases was supplied by multiple renal arteries, varying from 3 to 6. In three cases symmetrical arterial supply and in the rest asymmetrical supply was observed. Nephrolithiasis and hydronephrosis were noted in two patients. No other associated congenital anomaly was observed in all seven patients. Conclusion: Contrast enhanced multidetector computed tomography evaluation of patients with horseshoe kidney provide excellent information about its vascularity, collecting system and other associated conditions.

  8. Inter laboratory comparison on Industrial Computed Tomography

    DEFF Research Database (Denmark)

    Angel, Jais Andreas Breusch; De Chiffre, Leonardo; Larsen, Erik;

    The ‘CIA-CT comparison - Inter laboratory comparison on industrial Computed Tomography” is organized by DTU Department of Mechanical Engineering within the Danish project “Centre for Industrial Application of CT scanning - CIA-CT”. The project is co-financed by the Danish Ministry of Science......, Technology and Innovation. The comparison aims to collect information about measurement performance in state-of the-art industrial CT (Computed Tomography) scanning. Since CT scanning has entered the field of manufacturing and coordinate metrology, evaluation of uncertainty of measurement with assessment...

  9. Single photon emission computed tomography-guided Cerenkov luminescence tomography

    Science.gov (United States)

    Hu, Zhenhua; Chen, Xueli; Liang, Jimin; Qu, Xiaochao; Chen, Duofang; Yang, Weidong; Wang, Jing; Cao, Feng; Tian, Jie

    2012-07-01

    Cerenkov luminescence tomography (CLT) has become a valuable tool for preclinical imaging because of its ability of reconstructing the three-dimensional distribution and activity of the radiopharmaceuticals. However, it is still far from a mature technology and suffers from relatively low spatial resolution due to the ill-posed inverse problem for the tomographic reconstruction. In this paper, we presented a single photon emission computed tomography (SPECT)-guided reconstruction method for CLT, in which a priori information of the permissible source region (PSR) from SPECT imaging results was incorporated to effectively reduce the ill-posedness of the inverse reconstruction problem. The performance of the method was first validated with the experimental reconstruction of an adult athymic nude mouse implanted with a Na131I radioactive source and an adult athymic nude mouse received an intravenous tail injection of Na131I. A tissue-mimic phantom based experiment was then conducted to illustrate the ability of the proposed method in resolving double sources. Compared with the traditional PSR strategy in which the PSR was determined by the surface flux distribution, the proposed method obtained much more accurate and encouraging localization and resolution results. Preliminary results showed that the proposed SPECT-guided reconstruction method was insensitive to the regularization methods and ignored the heterogeneity of tissues which can avoid the segmentation procedure of the organs.

  10. Therapy response evaluation with positron emission tomography-computed tomography.

    Science.gov (United States)

    Segall, George M

    2010-12-01

    Positron emission tomography-computed tomography with F-18-fluorodeoxyglucose is widely used for evaluation of therapy response in patients with solid tumors but has not been as readily adopted in clinical trials because of the variability of acquisition and processing protocols and the absence of universal response criteria. Criteria proposed for clinical trials are difficult to apply in clinical practice, and gestalt impression is probably accurate in individual patients, especially with respect to the presence of progressive disease and complete response. Semiquantitative methods of determining tissue glucose metabolism, such as standard uptake value, can be a useful descriptor for levels of tissue glucose metabolism and changes in response to therapy if technical quality control measures are carefully maintained. The terms partial response, complete response, and progressive disease are best used in clinical trials in which the terms have specific meanings and precise definitions. In clinical practice, it may be better to use descriptive terminology agreed upon by imaging physicians and clinicians in their own practice. PMID:21147376

  11. Computed tomography to quantify tooth abrasion

    Science.gov (United States)

    Kofmehl, Lukas; Schulz, Georg; Deyhle, Hans; Filippi, Andreas; Hotz, Gerhard; Berndt-Dagassan, Dorothea; Kramis, Simon; Beckmann, Felix; Müller, Bert

    2010-09-01

    Cone-beam computed tomography, also termed digital volume tomography, has become a standard technique in dentistry, allowing for fast 3D jaw imaging including denture at moderate spatial resolution. More detailed X-ray images of restricted volumes for post-mortem studies in dental anthropology are obtained by means of micro computed tomography. The present study evaluates the impact of the pipe smoking wear on teeth morphology comparing the abraded tooth with its contra-lateral counterpart. A set of 60 teeth, loose or anchored in the jaw, from 12 dentitions have been analyzed. After the two contra-lateral teeth were scanned, one dataset has been mirrored before the two datasets were registered using affine and rigid registration algorithms. Rigid registration provides three translational and three rotational parameters to maximize the overlap of two rigid bodies. For the affine registration, three scaling factors are incorporated. Within the present investigation, affine and rigid registrations yield comparable values. The restriction to the six parameters of the rigid registration is not a limitation. The differences in size and shape between the tooth and its contra-lateral counterpart generally exhibit only a few percent in the non-abraded volume, validating that the contralateral tooth is a reasonable approximation to quantify, for example, the volume loss as the result of long-term clay pipe smoking. Therefore, this approach allows quantifying the impact of the pipe abrasion on the internal tooth morphology including root canal, dentin, and enamel volumes.

  12. Fluorescence Computed Tomography with Polychromatic Source Data

    International Nuclear Information System (INIS)

    Fluorescence computed tomography is a synchrotron imaging technique aiming at reconstructing the fluorescence emission within a sample object. For a polychromatic source hitting the object, the amount of fluorescence detected is defined by a linear equation. For the monochromatic case, the operator is a Generalized Attenuated Radon Transform (GART). The main goal is to reconstruct the density function, given the sinogram data and the weight function. An eficient iterative algorithm for the inversion of the GART was presented recently by the authors. This inversion can only be performed if the weight function is previously known, which means that μ = μ(·, ε) and λ are also known. For monochromatic XFCT (acronym for x-rays fluorescence computed tomography), the determination of λ is a dificult task, and we have considered the approximation λ ≈ μ, which is valid for low energies ranging from 3Kev to 10Kev. So, for solving our problem, the first step is to find μ given the polychromatic sinogram. There are different approaches for this in the literature. Recently, an elegant and efficient method for solving this problem was introduced, using a fixed point algorithm. Opposite to this, where μ(·, ε) needs to be computed for all ε element of E, we claim that the integral of μ(·, ε) for all ε has a physical meaning and provides a good aproximation for the solution. Also we present fast algorithm for computations.

  13. Positron computed tomography: current state, clinical results and future trends

    International Nuclear Information System (INIS)

    An overview is presented of positron computed tomography: its advantages over single photon emission tomography, its use in metabolic studies of the heart and chemical investigation of the brain, and future trends

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

    Science.gov (United States)

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

    2016-08-01

    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.

  15. 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

    Institute of Scientific and Technical Information of China (English)

    刘善平

    2012-01-01

    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.

  16. Computed tomography appearances of sclerosing encapsulating peritonitis

    Energy Technology Data Exchange (ETDEWEB)

    George, C. [Department of Radiology, Hull Royal Infirmary, Hull (United Kingdom)]. E-mail: cheriangeorge@hotmail.com; Al-Zwae, K. [Department of Radiology, Hull Royal Infirmary, Hull (United Kingdom); Nair, S. [Department of Radiology, Hull Royal Infirmary, Hull (United Kingdom); Cast, J.E.I. [Department of Radiology, Hull Royal Infirmary, Hull (United Kingdom)

    2007-08-15

    Sclerosing encapsulating peritonitis (SEP) is a serious complication of peritoneal dialysis (PD) characterized by thickened peritoneal membranes, which lead to decreased ultra-filtration and intestinal obstruction. Its early clinical features are nonspecific, and it is often diagnosed late following laparotomy and peritoneal biopsy, when the patient develops small bowel obstruction, which can be a life-threatening complication. However, this is changing with increasing awareness of computed tomography (CT) findings in SEP. CT can yield an early, non-invasive diagnosis that may improve patient outcome. We present a review of the CT appearances of SEP.

  17. Multidetector Computed Tomography in Acute Joint Fractures

    Energy Technology Data Exchange (ETDEWEB)

    Haapamaeki, V.V.; Kiuru, M.J.; Mustonen, A.O.; Koskinen, S.K. [Helsinki Univ. Central Hospital (Finland). Helsinki Medical Imaging Center

    2005-10-01

    Conventional radiography plays an essential diagnostic role in the primary evaluation of acute joint trauma. In complex fractures, however, computed tomography (CT) is an imaging modality often used second to radiography. As a result of technical breakthroughs in the field, multidetector CT (MDCT) allows faster imaging and better temporal, spatial, and contrast resolution compared with conventional single-slice spiral CT. MDCT with multiplanar reformation is helpful in disclosing fracture patterns, particularly in complex joint fractures, where they reveal occult fractures and show the exact number of fracture components and their degree of displacement.

  18. Computed tomography studies of human brain movements

    International Nuclear Information System (INIS)

    Rhythmic brain movements have been revealed by sets of sequential computed tomography scans of human brains (seen retrospectively to be normal). These scans have shown that both (unenhanced) brain parenchymal density and the shapes of the elements of the supratentorial ventricular/cisternal system are subject to wave motions having similar periods - ranging from 26 s through 56 s, 77-96 s, 109 s and 224 s to 224 X 2 s (or even longer), with good correlation between peak values. These motions, as well as phase variations between the waves, suggest a peristaltic movement of cerebrospinal fluid through the ventricular/cisternal system with progressive axial damping

  19. Emerging clinical applications of computed tomography

    Science.gov (United States)

    Liguori, Carlo; Frauenfelder, Giulia; Massaroni, Carlo; Saccomandi, Paola; Giurazza, Francesco; Pitocco, Francesca; Marano, Riccardo; Schena, Emiliano

    2015-01-01

    X-ray computed tomography (CT) has recently been experiencing remarkable growth as a result of technological advances and new clinical applications. This paper reviews the essential physics of X-ray CT and its major components. Also reviewed are recent promising applications of CT, ie, CT-guided procedures, CT-based thermometry, photon-counting technology, hybrid PET-CT, use of ultrafast-high pitch scanners, and potential use of dual-energy CT for material differentiations. These promising solutions and a better knowledge of their potentialities should allow CT to be used in a safe and effective manner in several clinical applications. PMID:26089707

  20. Computed tomography of cardiac pseudotumors and neoplasms.

    Science.gov (United States)

    Anavekar, Nandan S; Bonnichsen, Crystal R; Foley, Thomas A; Morris, Michael F; Martinez, Matthew W; Williamson, Eric E; Glockner, James F; Miller, Dylan V; Breen, Jerome F; Araoz, Philip A

    2010-07-01

    Important features of cardiac masses can be clearly delineated on cardiac computed tomography (CT) imaging. This modality is useful in identifying the presence of a mass, its relationship with cardiac and extracardiac structures, and the features that distinguish one type of mass from another. A multimodality approach to the evaluation of cardiac tumors is advocated, with the use of echocardiography, CT imaging and magnetic resonance imaging as appropriately indicated. In this article, various cardiac masses are described, including pseudotumors and true cardiac neoplasms, and the CT imaging findings that may be useful in distinguishing these rare entities are presented. PMID:20705174

  1. Comparison on Computed Tomography using industrial items

    DEFF Research Database (Denmark)

    Angel, Jais Andreas Breusch; De Chiffre, Leonardo

    2014-01-01

    In a comparison involving 27 laboratories from 8 countries, measurements on two common industrial items, a polymer part and a metal part, were carried out using X-ray Computed Tomography. All items were measured using coordinate measuring machines before and after circulation, with reference...... measurement uncertainties in the range 1.5–5.5 μm, showing a good stability over the 6 months of the circulation. The comparison has shown that CT measurements on the industrial parts used lie in the range 6–53 μm, with maximum values up to 158 μm....

  2. 64排螺旋CT泌尿系三维成像患者的护理%Nursing of patients undergoing 64-slice CT urography

    Institute of Scientific and Technical Information of China (English)

    高丽; 张金玲; 赵云霞; 申秀芬

    2009-01-01

    目的 探讨护理工作在64排螺旋CT泌尿系三维成像(MSCTU)中的价值.方法 240例患者应用64排螺旋CT进行泌尿系三维成像检查,检查前询问病史及碘过敏史,关注患者的心理状态,做好碘预试验;检查中认真观察患者,对可能出现的任何不良反应进行预判,并制订相应的措施;检查后对症处理出现的各种情况,并做好护理指导.结果 239例患者顺利完成检查,1例在扫描过程中出现药物外渗,扫描失败,经过重新扫描,获得满意图像.结论 利用64排螺旋CT行泌尿系三维成像检查,作为一种无创伤、费用相对较低、安全性高的检查技术,护理操作应贯穿检查的每一步.有效的护理措施直接影响检查结果的准确性,熟练的护理操作及耐心细致的心理护理是MSCTU检查中的重要环节.%Objective To discuss the value of nursing work in 64-slice CT urography. Methods 240 patients participated in the 64-slice CT urography, inquiring medical history and iodine allergic history, paying attention to their psychological state and finishing iodine preliminary test before examination, ob-serving patients carefully, pre-judging any possible adverse effect and formulating corresponding measures during the examination, giving expectant treatment according to the various condition and nursing instruc-tion. Results 239 patients passed through the examination smoothly, agents exosmosis happened in one case and led to failure, but satisfactory image was obtained after rescanning. Conclusions Nursing oper-ation penetrates every step of 64-slice CT urography, which is a non-traumatic, low-expense and high-safety examination. Effect nursing directly influences the accuracy of the results, proficient nursing opera-tion and patient psychological nursing is the important part of it.

  3. Relationship between renal volume calculated by using multislice computed tomography and glomerular filtration rate calculated by using the Cockcroft-Gault and modification of diet in renal disease equations in living kidney donors.

    Science.gov (United States)

    Adibi, Atoosa; Mortazavi, Mojgan; Shayganfar, Azin; Kamal, Sima; Azad, Roya; Aalinezhad, Marzieh

    2016-01-01

    It is essential to ascertain the state of health and renal function of potential kidney donors before organ removal. In this regard, one of the primary steps is to estimate the donor's glomerular filtration rate (GFR). For this purpose, the modification of diet in renal disease (MDRD) and the Cockcroft-Gault (CG) formulas has been used. However, these two formulas produce different results and finding new techniques with greater accuracy is required. Measuring the renal volume from computed tomography (CT) scan may be a valuable index to assess the renal function. This study was conducted to investigate the correlation between renal volume and the GFR values in potential living kidney donors referred to the multislice imaging center at Alzahra Hospital during 2014. The study comprised 66 subjects whose GFR was calculated using the two aforementioned formulas. Their kidney volumes were measured by using 64-slice CT angiography and the correlation between renal volume and GFR values were analyzed using the Statistical Package for the Social Science software. There was no correlation between the volume of the left and right kidneys and the MDRD-based estimates of GFR (P = 0.772, r = 0.036, P = 0.251, r = 0.143, respectively). A direct linear correlation was found between the volume of the left and right kidneys and the CG-based GFR values (P = 0.001, r = 0.397, P kidney volume derived from multislice CT scan can help predict the GFR value in kidney donors with normal renal function. The limitations of our study include the small sample size and the medium resolution of 64-slice multislice scanners. Further studies with larger sample size and using higher resolution scanners are warranted to determine the accuracy of this method in potential kidney donors. PMID:27424682

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

    NARCIS (Netherlands)

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

    2013-01-01

    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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2014-06-01

    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.

  6. Inter laboratory comparison on Industrial Computed Tomography

    DEFF Research Database (Denmark)

    Angel, Jais Andreas Breusch; De Chiffre, Leonardo

    An interlaboratory comparison on industrial X-ray Computed Tomography (CT) was organized by the Centre for Geometrical Metrology (CGM), Department of Mechanical Engineering, Technical University of Denmark (DTU) and carried out within the project “Centre for Industrial Application of CT scanning ...... for their measurements. The industrial items are suitable artefacts for CT measurements of this kind, and each participant has been offered to keep a set used for the measurements in the comparison.......An interlaboratory comparison on industrial X-ray Computed Tomography (CT) was organized by the Centre for Geometrical Metrology (CGM), Department of Mechanical Engineering, Technical University of Denmark (DTU) and carried out within the project “Centre for Industrial Application of CT scanning...... - CIA-CT”. In the comparison, 27 laboratories from 8 countries were involved, and CT scanned two items selected among common industrial parts: a polymer part and a metal part. Altogether, 27 sets of items were circulated in parallel to the participants. Different measurands are considered, encompassing...

  7. COMPUTED TOMOGRAPHY OF TOOTH RESORPTION IN CATS.

    Science.gov (United States)

    Lang, Linda G; Wilkinson, Thomas E; White, Tammy L; Farnsworth, Raelynn K; Potter, Kathleen A

    2016-09-01

    Tooth resorption is the most common dental disease in cats and can be a source of oral pain. The current clinical gold standard for diagnosis includes a combination of oral exam and dental radiography, however early lesions are not always detected. Computed tomography (CT) of the skull, including the dental arches, is a commonly performed diagnostic procedure, however the appearance of tooth resorption on CT and the diagnostic ability of CT to detect tooth resorption have not been evaluated. The purpose of this prospective, descriptive, diagnostic accuracy study was to characterize the CT appearance of tooth resorption in a sample of affected cats and to evaluate the sensitivity and specificity of CT for tooth resorption compared to the clinical gold standard of oral exam and intraoral dental radiography. Twenty-eight cat cadaver specimens were recruited for inclusion. Each specimen was evaluated using oral exam, intraoral dental radiography, and computed tomography (four different slice thicknesses). Each tooth was evaluated for the presence or absence of tooth resorption. Teeth with lesions and a subset of normal teeth were evaluated with histopathology. On CT, tooth resorption appeared as irregularly marginated hypoattenuating defects in the mineral attenuating tooth components, most commonly involving the root or cementoenamel junction. Sensitivity for CT detection of tooth resorption was fair to poor (42.2-57.7%) and specificity was good to excellent (92.8-96.3%). Findings from this study indicated that CT has high specificity but low sensitivity for detection of tooth resorption in cats.

  8. Emerging clinical applications of computed tomography

    Directory of Open Access Journals (Sweden)

    Liguori C

    2015-06-01

    Full Text Available Carlo Liguori,1 Giulia Frauenfelder,2 Carlo Massaroni,3 Paola Saccomandi,3 Francesco Giurazza,4 Francesca Pitocco,4 Riccardo Marano,5 Emiliano Schena,3 1Radiology Unit, AORN A Cardarelli, 2Radiology Unit, AOU Federico II, Naples, 3Measurement and Biomedical Instrumentation Unit, 4Radiology Unit, Università Campus Bio-Medico di Roma, 5Department of Radiological Sciences, Institute of Radiology, Catholic University of Rome, A Gemelli University Hospital, Rome, Italy Abstract: X-ray computed tomography (CT has recently been experiencing remarkable growth as a result of technological advances and new clinical applications. This paper reviews the essential physics of X-ray CT and its major components. Also reviewed are recent promising applications of CT, ie, CT-guided procedures, CT-based thermometry, photon-counting technology, hybrid PET-CT, use of ultrafast-high pitch scanners, and potential use of dual-energy CT for material differentiations. These promising solutions and a better knowledge of their potentialities should allow CT to be used in a safe and effective manner in several clinical applications. Keywords: computed tomography, X-ray, thermometry, dual-energy, ultrafast scanner, guidance, photon-counting technology

  9. Computed tomography of juvenile nasopharyngeal angiofibroma

    International Nuclear Information System (INIS)

    It is well known that computed tomography (CT) is useful in detecting accurately the location, extent, erosion and relationship of angiofibroma to surrounding structures such as pterygopalation fossa. It is well known that computed tomography (CT) is useful in detecting accurately the location, sphenoid sinus, and etc. CT of 20 patients with juvenile angiofibroma, which were examined for 5 yeas from February, 1979 to May, 1984 at Department of Radiology, Seoul National University Hospital, were retrospectively analyzed. The results were as follows: 1. All 20 patients of juvenile angiofibroma had tumors in nasopharynx and posterior nasal cavity showing homogeneously dense-enhancing soft tissue mass on CT. There was extension of the tumor from nasopharynx and posterior nasal cavity into paranasal sinus (60%, 12/20), pterygopalatine fossa (55%, 11/20), infratemporal fossa (30%, 6/20), posterior orbit (10%, 2/20) and cranial cavity (15%, 3/20). 2. Angiogrpahy usually adds little diagnostic information, but is still needed to identify the precise source of blood supply to the tumor, and to perform the pre-operative embolization. The use of CT has deferred angiography until just before surgery, permitting embolization at optimal time. 3. CT is almost always necessary to reveal accurately the full extent of the tumor, especially intracranial space in the axial and coronal planes with contrast enhancement. CT is useful both in diagnosis as a guide to angiography and in planning the adequate therapy of juvenile angiofibroma

  10. Introduction to neutron stimulated emission computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Floyd, Carey E Jr [Department of Biomedical Engineering and Department of Radiology, Duke Advanced Imaging Laboratories Box 2623DUMC, Duke University, Durham, NC 27710 (United States); Bender, Janelle E [Department of Biomedical Engineering and Department of Radiology, Duke Advanced Imaging Laboratories Box 2623DUMC, Duke University, Durham, NC 27710 (United States); Sharma, Amy C [Department of Biomedical Engineering and Department of Radiology, Duke Advanced Imaging Laboratories Box 2623DUMC, Duke University, Durham, NC 27710 (United States); Kapadia, Anuj [Department of Biomedical Engineering and Department of Radiology, Duke Advanced Imaging Laboratories Box 2623DUMC, Duke University, Durham, NC 27710 (United States); Xia, Jessie [Department of Biomedical Engineering and Department of Radiology, Duke Advanced Imaging Laboratories Box 2623DUMC, Duke University, Durham, NC 27710 (United States); Harrawood, Brian [Department of Radiology, Duke Advanced Imaging Laboratories Box 3202DUMC, Duke University, Durham, NC 27710 (United States); Tourassi, Georgia D [Department of Radiology, Duke Advanced Imaging Laboratories Box 3202DUMC, Duke University, Durham, NC 27710 (United States); Lo, Joseph Y [Department of Radiology, Duke Advanced Imaging Laboratories Box 3202DUMC, Duke University, Durham, NC 27710 (United States); Crowell, Alexander [Department of Physics and Triangle Universities Nuclear Laboratory, Duke University, Durham, NC 27710 (United States); Howell, Calvin [Department of Physics and Triangle Universities Nuclear Laboratory, Duke University, Durham, NC 27710 (United States)

    2006-07-21

    Neutron stimulated emission computed tomography (NSECT) is presented as a new technique for in vivo tomographic spectroscopic imaging. A full implementation of NSECT is intended to provide an elemental spectrum of the body or part of the body being interrogated at each voxel of a three-dimensional computed tomographic image. An external neutron beam illuminates the sample and some of these neutrons scatter inelastically, producing characteristic gamma emission from the scattering nuclei. These characteristic gamma rays are acquired by a gamma spectrometer and the emitting nucleus is identified by the emitted gamma energy. The neutron beam is scanned over the body in a geometry that allows for tomographic reconstruction. Tomographic images of each element in the spectrum can be reconstructed to represent the spatial distribution of elements within the sample. Here we offer proof of concept for the NSECT method, present the first single projection spectra acquired from multi-element phantoms, and discuss potential biomedical applications.

  11. 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

    International Nuclear Information System (INIS)

    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/m2 (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).

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

    International Nuclear Information System (INIS)

    Objectives: To assess the diagnostic accuracy of standard axial 64-slice chest CT compared to aortic valve image plane ECG-gated cardiac CT for bicuspid aortic valves. Materials and methods: The standard axial chest CT scans of 20 patients with known bicuspid aortic valves were blindly, randomly analyzed for (i) the appearance of the valve cusps, (ii) the largest aortic sinus area, (iii) the longest aortic cusp length, (iv) the thickest aortic valve cusp and (v) valve calcification. A second blinded reader independently analyzed the appearance of the valve cusps. Forty-two age- and sex-matched patients with known tricuspid aortic valves were used as controls. Retrospectively ECG-gated cardiac CT multiphase reconstructions of the aortic valve were used as the gold-standard. Results: Fourteen (21%) scans were scored as unevaluable (7 bicuspid, 7 tricuspid). Of the remainder, there were 13 evaluable bicuspid valves, ten of which showed an aortic valve line sign, while the remaining three showed a normal Mercedes-Benz appearance owing to fused valve cusps. The 35 evaluable tricuspid aortic valves all showed a normal Mercedes-Benz appearance (P = 0.001). Kappa analysis = 0.62 indicating good interobserver agreement for the aortic valve cusp appearance. Aortic sinus areas, aortic cusp lengths and aortic cusp thicknesses of ≥3.8 cm2, 3.2 cm and 1.6 mm respectively on standard axial chest CT best distinguished bicuspid from tricuspid aortic valves (P < 0.0001 for all). Of evaluable scans, the sensitivity, specificity, positive and negative predictive values of standard axial chest CT in diagnosing bicuspid aortic valves was 77% (CI 0.54–1.0), 100%, 100% and 70% respectively. Conclusion: The aortic valve is evaluable in approximately 80% of standard chest 64-slice CT scans. Bicuspid aortic valves may be diagnosed on evaluable scans with good diagnostic accuracy. An aortic valve line sign, enlarged aortic sinuses and elongated, thickened valve cusps are specific CT

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

    International Nuclear Information System (INIS)

    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/m2 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. Computed tomography for preoperative planning in minimal-invasive total hip arthroplasty: Radiation exposure and cost analysis

    Energy Technology Data Exchange (ETDEWEB)

    Huppertz, Alexander, E-mail: Alexander.Huppertz@charite.de [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: s.radmer@immanuel.de [Department of Orthopedic Surgery and Rheumatology, Immanuel-Krankenhaus, Koenigstr. 63, D-14109, Berlin (Germany); Asbach, Patrick, E-mail: Patrick.Asbach@charite.de [Department of Radiology, Medical Physics, Charite-University Hospitals of Berlin, Chariteplatz 1, D-10117 Berlin (Germany); Juran, Ralf, E-mail: ralf.juran@charite.de [Department of Radiology, Medical Physics, Charite-University Hospitals of Berlin, Chariteplatz 1, D-10117 Berlin (Germany); Schwenke, Carsten, E-mail: carsten.schwenke@scossis.de [Biostatistician, Scossis Statistical Consulting, Zeltinger Str. 58G, D-13465 Berlin (Germany); Diederichs, Gerd, E-mail: gerd.diederichs@charite.de [Department of Radiology, Medical Physics, Charite-University Hospitals of Berlin, Chariteplatz 1, D-10117 Berlin (Germany); Hamm, Bernd, E-mail: Bernd.Hamm@charite.de [Department of Radiology, Medical Physics, Charite-University Hospitals of Berlin, Chariteplatz 1, D-10117 Berlin (Germany); Sparmann, Martin, E-mail: m.sparmann@immanuel.de [Department of Orthopedic Surgery and Rheumatology, Immanuel-Krankenhaus, Koenigstr. 63, D-14109, Berlin (Germany)

    2011-06-15

    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.

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

    Energy Technology Data Exchange (ETDEWEB)

    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)

    2014-05-15

    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.)

  16. Spatiotemporal computed tomography of dynamic processes

    Science.gov (United States)

    Kaestner, Anders; Münch, Beat; Trtik, Pavel; Butler, Les

    2011-12-01

    Modern computed tomography (CT) equipment allowing fast 3-D imaging also makes it possible to monitor dynamic processes by 4-D imaging. Because the acquisition time of various 3-D-CT systems is still in the range of at least milliseconds or even hours, depending on the detector system and the source, the balance of the desired temporal and spatial resolution must be adjusted. Furthermore, motion artifacts will occur, especially at high spatial resolution and longer measuring times. We propose two approaches based on nonsequential projection angle sequences allowing a convenient postacquisition balance of temporal and spatial resolution. Both strategies are compatible with existing instruments, needing only a simple reprograming of the angle list used for projection acquisition and care with the projection order list. Both approaches will reduce the impact of artifacts due to motion. The strategies are applied and validated with cold neutron imaging of water desorption from originally saturated particles during natural air-drying experiments and with x-ray tomography of a polymer blend heated during imaging.

  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

    OpenAIRE

    Ergun, Elif; Haberal, Murat; Koşar, Pınar; Yılmaz, Ali; Koşar, Uğur

    2011-01-01

    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 imag...

  18. 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

    OpenAIRE

    Elif Ergun; Murat Haberal; Pınar Koşar; Ali Yılmaz; Uğur Koşar

    2011-01-01

    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 ...

  19. Perfusion computed tomography imaging of autoimmune pancreatitis

    International Nuclear Information System (INIS)

    Perfusion computed tomography (P-CT) is now available for the analysis of pancreatic blood flow. The aim of this study was to clarify pancreatic blood perfusion in AIP patients and the changes after steroid treatment. Color map imaging of P-CT and pancreatic time CT density curve (TDC) demonstrated that the pancreatic blood flow was attenuated in AIP patients. Pancreatic volumetric blood flow FV values of 11 AIP patients (82.7/min) were significantly lower than those of 12 normal controls (163.5/min, p=0.0006). AIP patients received steroid treatment and were re-examined, of these, 9 patients showed significantly elevated FV values after treatment (76.2/min and 109.8/min, p=0.0391, respectively). However, the changes of the values after the treatment differed in varying degrees among the individuals. P-CT is a useful method for the analysis of the blood flow in pancreatic diseases. (author)

  20. Coordinate Metrology by Traceable Computed Tomography

    DEFF Research Database (Denmark)

    Müller, Pavel

    is a well-established technique for tolerance verification of manufactured parts. Two reference objects for performance characterization of industrial CT systems were developed within the scope of the Ph.D. thesis. Namely, CT ball plate and CT tree, which were further used for identification......X-ray computed tomography (CT) is a measuring technique which has become an important technology in the production environment over the last years. Due to a number of advantages of CT compared to, e.g., coordinate measuring machines (CMMs), CT has been recently spread in the field of manufacturing...... is an important factor for decision making about manufactured parts. However, due to many influences in CT, estimation of the uncertainty is a challenge, also because standardized procedures and guidelines are not available yet. In this thesis, several methods for uncertainty estimation were applied in connection...

  1. Polychromatic phase-contrast computed tomography

    International Nuclear Information System (INIS)

    Polychromatic phase-contrast radiography differs from traditional (absorption-only) radiography in that the method requires at least a partially coherent x-ray source and the resulting images contain information about the phase shifts of x-rays in addition to the traditional absorption information. In a typical embodiment, this effect results in a measurable enhancement in image contrast at the edges of objects. In this study, a phase-contrast imaging system was adapted to allow an object to be imaged at multiple projections, and these projections were used to generate phase-contrast computed tomography images. The images obtained with this technique show edge enhancements surrounding the objects within the image

  2. Data processing device for computed tomography system

    International Nuclear Information System (INIS)

    A data processing device applied to a computed tomography system which examines a living body utilizing radiation of X-rays is disclosed. The X-rays which have penetrated the living body are converted into electric signals in a detecting section. The electric signals are acquired and converted from an analog form into a digital form in a data acquisition section, and then supplied to a matrix data-generating section included in the data processing device. By this matrix data-generating section are generated matrix data which correspond to a plurality of projection data. These matrix data are supplied to a partial sum-producing section. The partial sums respectively corresponding to groups of the matrix data are calculated in this partial sum-producing section and then supplied to an accumulation section. In this accumulation section, the final value corresponding to the total sum of the matrix data is calculated, whereby the calculation for image reconstruction is performed

  3. Advanced proton imaging in computed tomography

    CERN Document Server

    Mattiazzo, S; Giubilato, P; Pantano, D; Pozzobon, N; Snoeys, W; Wyss, J

    2015-01-01

    In recent years the use of hadrons for cancer radiation treatment has grown in importance, and many facilities are currently operational or under construction worldwide. To fully exploit the therapeutic advantages offered by hadron therapy, precise body imaging for accurate beam delivery is decisive. Proton computed tomography (pCT) scanners, currently in their R&D phase, provide the ultimate 3D imaging for hadrons treatment guidance. A key component of a pCT scanner is the detector used to track the protons, which has great impact on the scanner performances and ultimately limits its maximum speed. In this article, a novel proton-tracking detector was presented that would have higher scanning speed, better spatial resolution and lower material budget with respect to present state-of-the-art detectors, leading to enhanced performances. This advancement in performances is achieved by employing the very latest development in monolithic active pixel detectors (to build high granularity, low material budget, ...

  4. Imaging of Cardiac Valves by Computed Tomography

    Directory of Open Access Journals (Sweden)

    Gudrun Feuchtner

    2013-01-01

    Full Text Available This paper describes “how to” examine cardiac valves with computed tomography, the normal, diseased valves, and prosthetic valves. A review of current scientific literature is provided. Firstly, technical basics, “how to” perform and optimize a multislice CT scan and “how to” interpret valves on CT images are outlined. Then, diagnostic imaging of the entire spectrum of specific valvular disease by CT, including prosthetic heart valves, is highlighted. The last part gives a guide “how to” use CT for planning of transcatheter aortic valve implantation (TAVI, an emerging effective treatment option for patients with severe aortic stenosis. A special focus is placed on clinical applications of cardiac CT in the context of valvular disease.

  5. Computed tomography findings of malignant pleural mesothelioma

    International Nuclear Information System (INIS)

    Computed tomography (CT) findings were assessed in 7 patients with malignant mesothelioma. CT findings were also reviewed in 9 patients with lung cancer and pleuritis carcinomatosa and in 11 patients with tuberculous pleuritis. Five patients with malignant mesothelioma underwent CT scans twice, on admission and from 1 to 7 months after admission. Tuberculous pleuritis could be distinguished from pleuritis carcinomatosa and malignant mesothelioma by the presence or absence of pleural nodularity and chest wall invasion. Although it was difficult to identify specific CT features clearly distinguishing malignant mesothelioma from pleuritis carcinomatosa, characteristic findings of malignant mesothelioma appeared to include the rapid development and progression of pleural rind and a tendency to spread directly into the chest wall. We divided the pleural into the four regions; upper anterior, upper posterior, lower anterior and lower posterior regions. Pleural changes were more frequently seen in the lower pleural regions than in the upper pleural regions in malignant mesothelioma. (author)

  6. Computed tomography findings in convergent strabismus fixus

    Energy Technology Data Exchange (ETDEWEB)

    Ohta, Michitaka; Iwashige, Hiroyasu; Hayashi, Takao; Maruo, Toshio [Teikyo Univ., Tokyo (Japan). Faculty of Medicine

    1995-08-01

    X-ray computed tomography (CT) of the eyeball and orbit revealed the cause of eye movement disorder in convergent strabismus fixus. The findings suggest that the disease can be diagnosed and treated at an early stage. Twelve cases of progressive esotropia with high myopia and 20 cases with normal visual acuity served as subjects in this study. The CT slice was parallel to the German horizontal plane, and the lens and medial and lateral rectus muscles were scanned. The average axial length of the affected eyes was significantly longer than in normal eyes. In progressive esotropia, the characteristic CT findings are an elongated eyeball, mechanical contact between the eyeball and lateral wall of the orbit, and a downward displacement of the lateral rectus muscle. Thus, it is reasonable to conclude that eye movement disorder in convergent strabismus fixus results from weakness of the lateral rectus muscle which has been displaced downward due to compression of the eyeball against the orbital wall. (author).

  7. Sparse Image Reconstruction in Computed Tomography

    DEFF Research Database (Denmark)

    Jørgensen, Jakob Sauer

    and limitations of sparse reconstruction methods in CT, in particular in a quantitative sense. For example, relations between image properties such as contrast, structure and sparsity, tolerable noise levels, suficient sampling levels, the choice of sparse reconstruction formulation and the achievable image...... quality remain unclear. This is a problem of high practical concern, because the large scale of CT problems makes detailed exploration of the parameter space very time-consuming. Due to the limited quantitative understanding, sparse reconstruction has not yet become the method of choice in practical CT......In recent years, increased focus on the potentially harmful effects of x-ray computed tomography (CT) scans, such as radiation-induced cancer, has motivated research on new low-dose imaging techniques. Sparse image reconstruction methods, as studied for instance in the field of compressed sensing...

  8. PRIMA+: a proton computed tomography apparatus

    International Nuclear Information System (INIS)

    The proton Computed Tomography (pCT) is a medical imaging method, based on the use of proton beams with kinetic energy of the order of 250 MeV, aimed to directly measure the stopping power distribution of tissues thus improving the present accuracy of treatment planning in hadron therapy. A pCT system should be capable to measure tissue electron density with an accuracy better than 1% and a spatial resolution better than 1 mm. The blurring effect due to multiple Coulomb scattering can be mitigated by single proton tracking technique. As a first step towards pCT the PRIMA+ Collaboration built a prototype capable to carry out a single radiography and a tomographic image of a rotating object. This apparatus includes a silicon microstrip tracker to identify the proton trajectory and a YAG:Ce calorimeter to measure the particle residual energy.

  9. Computer tomography of intracranial tumours and hematomas

    International Nuclear Information System (INIS)

    The value of computed tomography (CT) for the diagnosis of intracranial tumors and hematomas was investigated in a retrospective study comprising 220 patients. All C.T.scans are reviewed and described in detail. To assess the diagnostic accuracy, the original interpretation of the C.T.scans was compared with that of conventional neuroradiological and neurophysiological examinations. The aspect on C.T. of the various types of tumors and hematomas proved to vary widely and specific features were seldom seen. This holds particularly for the malignant tumors. Benign tumors such as meningeomas, adenomas and neurilemmomas showed a rather easily identifiable and almost identical picture of the C.T.scan, and diagnosis had to be based mainly on differences in localization. The hematomas, with the exception of the older intracerebral ones, showed the most characteristic C.T.abnormalities. (Auth.)

  10. Radiation Protection in Paediatric Computed Tomography

    International Nuclear Information System (INIS)

    The number of examinations with radiation exposure has been increasing mainly due to advances in computed tomography (CT) technology, with a rapid expansion of CT utilization. Annually, 3.6 billion diagnostic and medical and dental examinations involving radiation are performed worldwide. The contribution of CT to collective dose due to medical X rays is up to 47–59%. A 2009 report of the National Council on Radiation Protection and Measurements (NCRP) estimates that 8–10% of CT examinations in the United States of America are performed on children; the growth in CT utilization is higher in the paediatric than adult population in the USA; and there is a particularly pronounced rise in adolescents undergoing chest CT in the emergency department setting for suspected pulmonary embolism or trauma. The reasons for the growing incidence of CT are new indications for CT with the advent of multidetector CT, overcautious ordering related to medico-legal problems and probably financial incentive systems

  11. Radiation Protection of Patients in Computed Tomography

    International Nuclear Information System (INIS)

    The use of radiation for medical diagnostic examinations contributes over 95% of human-made radiation exposure and is only exceeded by natural background as a source of exposure to the world’s population. In fact, for several developed countries, the increased use of high dose X ray technology, in particular, computed tomography (CT), has resulted in a situation in which the annual collective and per capita doses of ionizing radiation due to diagnostic radiology have exceeded those from natural background radiation. In light of this marked increase in worldwide collective effective dose from medical diagnostic procedures, and with CT scans accounting for half of this, there is great emphasis on the subject of radiation protection of patients in CT

  12. Myocardial hypoperfusion on conventional contrast computed tomography.

    Science.gov (United States)

    Ching, Shing; Chung, Tak Shun

    2015-10-01

    Non–electrocardiogram (ECG)–gated contrast computed tomography (CT) is commonly performed to exclude aortic dissection in chest pain patients. Besides evaluating the aorta for dissection flap, attention should be paid to the myocardium for areas of hypoenhancement that may suggest ischemia. Current models of multidetector CT enable assessment of myocardial perfusion with minimal motion artifact even without ECG gating. Transmural hypoenhancement with preserved wall thickness in a coronary distribution is highly specific for acute myocardial infarction. We report 2 cases of acute chest pain with initial nondiagnostic studies that underwent CT aortogram to exclude dissection. Instead, the CT showed myocardial hypoenhancement in left anterior descending artery territory. Myocardial hypoenhancement occurred before ST-segment elevation on ECG, suggesting that recognition of this important finding may lead to earlier revascularization decisions. PMID:26321167

  13. Neutron stimulated emission computed tomography: Background corrections

    Energy Technology Data Exchange (ETDEWEB)

    Floyd, Carey E. [Dept. of Biomedical Engineering, Duke University, Durham, NC 27708 (United States)]|[Duke Advanced Imaging Laboratories, Dept. of Radiology, Duke University, Durham, NC 27708 (United States)]|[Medical Physics Graduate Program, Duke University, Durham, NC 27708 (United States); Sharma, Amy C. [Dept. of Biomedical Engineering, Duke University, Durham, NC 27708 (United States)]|[Duke Advanced Imaging Laboratories, Dept. of Radiology, Duke University, Durham, NC 27708 (United States); E-mail: anc4@duke.edu; Bender, Janelle E.; Kapadia, Anuj J.; Xia, Jessie Q. [Dept. of Biomedical Engineering, Duke University, Durham, NC 27708 (United States)]|[Duke Advanced Imaging Laboratories, Dept. of Radiology, Duke University, Durham, NC 27708 (United States); Harrawood, Brian P. [Duke Advanced Imaging Laboratories, Dept. of Radiology, Duke University, Durham, NC 27708 (United States); Tourassi, Georgia D. [Duke Advanced Imaging Laboratories, Dept. of Radiology, Duke University, Durham, NC 27708 (United States); Lo, Joseph Y. [Dept. of Biomedical Engineering, Duke University, Durham, NC 27708 (United States)]|[Duke Advanced Imaging Laboratories, Dept. of Radiology, Duke University, Durham, NC 27708 (United States)]|[Medical Physics Graduate Program, Duke University, Durham, NC 27708 (United States); Kiser, Matthew R.; Crowell, Alexander S. [Dept. of Physics and Triangle Universities Nuclear Laboratory, Duke University, Durham, NC 27708 (United States); Pedroni, Ronald S. [North Carolina A and T State University, Greensboro, NC (United States); Macri, Robert A. [Lawrence Livermore National Laboratory, Livermore, CA (United States); Tajima, Shigeyuki [Dept. of Physics, University of Virginia, Charlottesville, VA (United States); Howell, Calvin R. [Medical Physics Graduate Program, Duke University, Durham, NC 27708 (United States)]|[Dept. of Physics and Triangle Universities Nuclear Laboratory, Duke University, Durham, NC 27708 (United States)

    2007-01-15

    Neutron stimulated emission computed tomography (NSECT) is an imaging technique that provides an in-vivo tomographic spectroscopic image of the distribution of elements in a body. To achieve this, a neutron beam illuminates the body. Nuclei in the body along the path of the beam are stimulated by inelastic scattering of the neutrons in the beam and emit characteristic gamma photons whose unique energy identifies the element. The emitted gammas are collected in a spectrometer and form a projection intensity for each spectral line at the projection orientation of the neutron beam. Rotating and translating either the body or the beam will allow a tomographic projection set to be acquired. Images are reconstructed to represent the spatial distribution of elements in the body. Critical to this process is the appropriate removal of background gamma events from the spectrum. Here we demonstrate the equivalence of two background correction techniques and discuss the appropriate application of each.

  14. Ultra-high resolution computed tomography imaging

    Energy Technology Data Exchange (ETDEWEB)

    Paulus, Michael J. (Knoxville, TN); Sari-Sarraf, Hamed (Knoxville, TN); Tobin, Jr., Kenneth William (Harriman, TN); Gleason, Shaun S. (Knoxville, TN); Thomas, Jr., Clarence E. (Knoxville, TN)

    2002-01-01

    A method for ultra-high resolution computed tomography imaging, comprising the steps of: focusing a high energy particle beam, for example x-rays or gamma-rays, onto a target object; acquiring a 2-dimensional projection data set representative of the target object; generating a corrected projection data set by applying a deconvolution algorithm, having an experimentally determined a transfer function, to the 2-dimensional data set; storing the corrected projection data set; incrementally rotating the target object through an angle of approximately 180.degree., and after each the incremental rotation, repeating the radiating, acquiring, generating and storing steps; and, after the rotating step, applying a cone-beam algorithm, for example a modified tomographic reconstruction algorithm, to the corrected projection data sets to generate a 3-dimensional image. The size of the spot focus of the beam is reduced to not greater than approximately 1 micron, and even to not greater than approximately 0.5 microns.

  15. Computed tomography and magnetic resonance findings in lipoid pneumonia.

    OpenAIRE

    Bréchot, J M; Buy, J N; Laaban, J P; Rochemaure, J

    1991-01-01

    A case of exogenous lipoid pneumonia was documented by computed tomography and magnetic resonance imaging. Although strongly suggesting the presence of fat on T1 weighted images, magnetic resonance does not produce images specific for this condition. Computed tomography is the best imaging modality for its diagnosis.

  16. Diagnosis of lumbar disc hernia with computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Yoshizumi, Atsuro; Ohira, Nobuhiro; Ojima, Tadashi; Oshida, Midori; Horaguchi, Mitsuru (Tohoku Rosai Hospital, Sendai (Japan))

    1982-07-01

    Results of computed tomography performed on patients with clinically diagnosed hernia were compared with those of myelography and operative findings. This comparative study suggested that computed tomography is quite different from other methods and very useful in diagnosis of hernia. Some cases of hernia were shown, and the characteristics of CT were reviewed.

  17. The role of computed tomography in the laryngeal injury

    Energy Technology Data Exchange (ETDEWEB)

    Bae, Hoon Sik [Capital Armed Forces General Hospital, Seongnam (Korea, Republic of)

    1984-03-15

    Computed tomography of the larynx represents a major advance in laryngology. Even in severe injury the larynx can be examined easily and conveniently by CT at the same time as the brain and facial structures without moving the patient, who need only lie down and breathe quietly during the study. Computed tomography permitted a much more detailed appraisal of laryngeal dysfunction in patients with blunt laryngeal trauma (3 cases) and strangulation injury (2 cases). Computed tomography of the larynx undoubtedly played a determinant role in patient management. Computed tomography was helpful in evaluating the laryngeal cartilages and deep spaces of the larynx which was difficult to examine by the laryngoscope. Follow-up computed tomography made it possible to evaluate the postoperative results.

  18. Terahertz Computed Tomography of NASA Thermal Protection System Materials

    Science.gov (United States)

    Roth, D. J.; Reyes-Rodriguez, S.; Zimdars, D. A.; Rauser, R. W.; Ussery, W. W.

    2011-01-01

    A terahertz axial computed tomography system has been developed that uses time domain measurements in order to form cross-sectional image slices and three-dimensional volume renderings of terahertz-transparent materials. The system can inspect samples as large as 0.0283 cubic meters (1 cubic foot) with no safety concerns as for x-ray computed tomography. In this study, the system is evaluated for its ability to detect and characterize flat bottom holes, drilled holes, and embedded voids in foam materials utilized as thermal protection on the external fuel tanks for the Space Shuttle. X-ray micro-computed tomography was also performed on the samples to compare against the terahertz computed tomography results and better define embedded voids. Limits of detectability based on depth and size for the samples used in this study are loosely defined. Image sharpness and morphology characterization ability for terahertz computed tomography are qualitatively described.

  19. Detection of a coronary artery vessel wall: performance of 0.3 mm fine-cell detector computed tomography-a phantom study

    Energy Technology Data Exchange (ETDEWEB)

    Yamada, Minoru [Multi-dimension Biomedical Imaging and Information Laboratory in Research Park, Keio University School of Medicine, Tokyo (Japan); Jinzaki, Masahiro; Tanami, Yutaka; Matsumoto, Kazuhiro; Ueno, Akihisa; Kuribayashi, Sachio [Department of Diagnostic Radiology, Keio University School of Medicine, Tokyo (Japan); Nukui, Masatake; Imai, Yasuhiro; Ishihara, Yotaro; Nishide, Akihiko; Sasaki, Kosuke, E-mail: jinzaki@rad.med.keio.ac.jp [CT Engineering, GE Healthcare Japan, Tokyo (Japan)

    2011-08-21

    The purpose of this study was to evaluate whether experimental fine-cell detector computed tomography with a 0.3125 mm cell (0.3 mm cell CT) can improve the detection of coronary vessel walls compared with conventional 64-slice computed tomography with a 0.625 mm cell (0.6 mm cell CT). A coronary vessel wall phantom was scanned using 0.6 mm cell CT and 0.3 mm cell CT. The data for 0.3 mm cell CT were obtained using four protocols: a radiation dose equal, double, triple or quadruple that were used in the 0.6 mm cell CT protocol. The detectable size of the vessel wall was assessed based on the first and second derivative functions, and the minimum measurable values were compared using a paired t-test. As a result, the minimum detectable wall thickness of 0.6 mm cell CT (1.5 mm) was significantly larger than that of 0.3 mm cell CT performed using the triple- and quadruple-dose protocols (0.9 mm) and the double-dose protocol (1.1 mm). The difference in the minimum detectable vessel wall thickness measured using 0.6 mm cell CT (1.5 {+-} 0.1 mm) and 0.3 mm cell CT (0.9 {+-} 0.1 mm, 1.1 {+-} 0.2 mm) was significant (p < 0.01). We concluded that 0.3 mm cell CT improved the detection of coronary vessel walls when a more than double-dose protocol was used compared with 0.6 mm cell CT.

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

    Energy Technology Data Exchange (ETDEWEB)

    Murphy, David J., E-mail: david.murphy@st-vincents.ie [Department of Radiology, St Vincent' s University Hospital, Elm Park, Dublin 4 (Ireland); McEvoy, Sinead H., E-mail: s.mcevoy@st-vincents.ie [Department of Radiology, St Vincent' s University Hospital, Elm Park, Dublin 4 (Ireland); Iyengar, Sri, E-mail: sri.iyengar@nhs.net [Department of Radiology, Plymouth Hospitals NHS Trust, Plymouth Devon PL6 8DH (United Kingdom); Feuchtner, Gudrun, E-mail: Gudrun.Feuchtner@i-med.ac.at [Department of Radiology, Innsbruck Medical University, Anichstr. 35, A-6020 Innsbruck (Austria); Cury, Ricardo C., E-mail: r.cury@baptisthealth.net [Department of Radiology, Baptist Cardiac and Vascular Institute, 8900 North Kendall Drive, Miami, FL 33176 (United States); Roobottom, Carl, E-mail: carl.roobottom@nhs.net [Department of Radiology, Plymouth Hospitals NHS Trust, Plymouth Devon PL6 8DH (United Kingdom); Plymouth University Peninsula Schools of Medicine and Dentistry (United Kingdom); Baumueller, Stephan, E-mail: Hatem.Alkadhi@usz.ch [Institute for Diagnostic and Interventional Radiology, University Hospital Zurich, Raemistrasse 100, CH-8091 Zurich (Switzerland); Alkadhi, Hatem, E-mail: stephan.baumueller@usz.ch [Institute for Diagnostic and Interventional Radiology, University Hospital Zurich, Raemistrasse 100, CH-8091 Zurich (Switzerland); Dodd, Jonathan D., E-mail: jonniedodd@gmail.com [Department of Radiology, St Vincent' s University Hospital, Elm Park, Dublin 4 (Ireland)

    2014-08-15

    Objectives: To assess the diagnostic accuracy of standard axial 64-slice chest CT compared to aortic valve image plane ECG-gated cardiac CT for bicuspid aortic valves. Materials and methods: The standard axial chest CT scans of 20 patients with known bicuspid aortic valves were blindly, randomly analyzed for (i) the appearance of the valve cusps, (ii) the largest aortic sinus area, (iii) the longest aortic cusp length, (iv) the thickest aortic valve cusp and (v) valve calcification. A second blinded reader independently analyzed the appearance of the valve cusps. Forty-two age- and sex-matched patients with known tricuspid aortic valves were used as controls. Retrospectively ECG-gated cardiac CT multiphase reconstructions of the aortic valve were used as the gold-standard. Results: Fourteen (21%) scans were scored as unevaluable (7 bicuspid, 7 tricuspid). Of the remainder, there were 13 evaluable bicuspid valves, ten of which showed an aortic valve line sign, while the remaining three showed a normal Mercedes-Benz appearance owing to fused valve cusps. The 35 evaluable tricuspid aortic valves all showed a normal Mercedes-Benz appearance (P = 0.001). Kappa analysis = 0.62 indicating good interobserver agreement for the aortic valve cusp appearance. Aortic sinus areas, aortic cusp lengths and aortic cusp thicknesses of ≥3.8 cm{sup 2}, 3.2 cm and 1.6 mm respectively on standard axial chest CT best distinguished bicuspid from tricuspid aortic valves (P < 0.0001 for all). Of evaluable scans, the sensitivity, specificity, positive and negative predictive values of standard axial chest CT in diagnosing bicuspid aortic valves was 77% (CI 0.54–1.0), 100%, 100% and 70% respectively. Conclusion: The aortic valve is evaluable in approximately 80% of standard chest 64-slice CT scans. Bicuspid aortic valves may be diagnosed on evaluable scans with good diagnostic accuracy. An aortic valve line sign, enlarged aortic sinuses and elongated, thickened valve cusps are specific CT

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

    Directory of Open Access Journals (Sweden)

    "A. Arjmand Shabestari

    2005-08-01

    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

  2. Computed tomography of traumatic intracranial lesions

    International Nuclear Information System (INIS)

    The cranial computed tomography (CT) is a new radiological technique with which, for the first time, minimal differences an attenuation by intracranial soft tissue can be measured exactly. The basic physical principles of computed tomography have been extensively presented by Hounsfield (1973). It is well established that the attenuation of extravasated blood measures between 35 and 45 Hounsfield units. Therefore no difficulty should be encountered in the recognition and diagnosis of extra-axial hematoma and cerebral contusion since the density of the brain parenchyma never measures more than 25 units. As the constant increase in high velocity accidents and violence, the problem of acute head injury is one of the matters of great importance in today's medical practice. Therefore it is very important to figure out the method that would allow us to diagnose easily and precisely the effects of trauma upon the brain in order to institute the proper treatment at the earliest possible moment. Computed tomography allows us to make a diagnosis quickly and in a non-invasive manner. The CT scan was carried out on 310 head trauma cases in the department of radiology, St. Mary's and Kang Nam St. Mary's Hospital, Catholic Medical College, for 16 months from June 1979 to October 1980. All the scans were obtained with the Hitachi CT-H2 scanner and the scans were repeated following intravenous injection of high dose of contrast media (roughly 1.8 cc per kg body weight of 60% Conray). We have reviewed the CT scans of 310 patients got acute head injury in order to assess the location of brain lesions, the relationship between the CT densities of hematomas and their stage, the shape and mass effect of the extra-axial hematomas, and the effect of contrast enhancement. The results were as follows: 1. Of all 310 cases of the head injuries, epidural hematoma was 13.5%, subdural hematoma was 8.7%, subdural hygroma was 10%, cerebral contusion was 39%, hydrocephalus and atrophy was 3.9% and

  3. Giant hepatic cavernous hemangioma. Findings on computed helical tomography

    International Nuclear Information System (INIS)

    Objective: To describe computed helical tomography characteristics of the giant hepatic cavernous hemangioma. Method: During five years, we evaluated 21 patients with 21 giant hepatic cavernous hemangiomas with computed helical and multislice tomography. We included 18 women (86%) and 3 men (14%) with a mean age of 45 years. Results: The mean size of hemangiomas was 10.4 cm. Non enhanced computed tomography Showed 21 hemangiomas with lower density than adjacent hepatic parenchyma , all hemangiomas showed a central cleft area with low density. None hemangioma showed calcifications neither internal septa. In enhanced helical tomography all lesions demonstrated a globular, peripheral enhancing pattern with centripetal filling that begin in the arterial phase and continued in portal and delayed phases. None of the lesions showed complete filling. Conclusion: giant hepatic cavernous hemangiomas showed low attenuation in non enhanced computed tomography. central cleft area was very frequently seen. The enhancement pattern is characteristic, starting at the periphery with centripetal filling but it was never complete.

  4. Reproducibility in the assessment of acute pancreatitis with computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Freire Filho, Edison de Oliveira; Vieira, Renata La Rocca; Yamada, Andre Fukunishi; Shigueoka, David Carlos; Bekhor, Daniel; Freire, Maxime Figueiredo de Oliveira; Ajzen, Sergio; D' Ippolito, Giuseppe [Universidade Federal de Sao Paulo (UNIFESP/EPM), SP (Brazil). Dept. of Imaging Diagnosis]. E-mail: eofilho@ig.com.br; eoffilho@uol.com.br

    2007-11-15

    Objective: To evaluate the reproducibility of unenhanced and contrast-enhanced computed tomography in the assessment of patients with acute pancreatitis. Materials and methods: Fifty-one unenhanced and contrast-enhanced abdominal computed tomography studies of patients with acute pancreatitis were blindly reviewed by two radiologists (observers 1 and 2). The morphological index was separately calculated for unenhanced and contrast-enhanced computed tomography and the disease severity index was established. Intraobserver and interobserver reproducibility of computed tomography was measured by means of the kappa index ({kappa}). Results: Interobserver agreement was {kappa} 0.666, 0.705, 0.648, 0.547 and 0.631, respectively for unenhanced and contrast-enhanced morphological index, presence of pancreatic necrosis, pancreatic necrosis extension, and disease severity index. Intraobserver agreement (observers 1 and 2, respectively) was {kappa} = 0.796 and 0.732 for unenhanced morphological index; {kappa} 0.725 and 0.802 for contrast- enhanced morphological index; {kappa} = 0.674 and 0.849 for presence of pancreatic necrosis; {kappa} = 0.606 and 0.770 for pancreatic necrosis extension; and {kappa} = 0.801 and 0.687 for disease severity index at computed tomography. Conclusion: Computed tomography for determination of morphological index and disease severity index in the staging of acute pancreatitis is a quite reproducible method. The absence of contrast- enhancement does not affect the computed tomography morphological index reproducibility. (author)

  5. Analysis of the computed tomography in the acute abdomen

    International Nuclear Information System (INIS)

    Introduction: This study tends to test the capacity of the computed tomography in assist in the diagnosis and the approach of the acute abdomen. Material and method: This is a longitudinal and prospective study, in which were analyzed the patients with the diagnosis of acute abdomen. There were obtained 105 cases of acute abdomen and after the application of the exclusions criteria were included 28 patients in the study. Results: Computed tomography changed the diagnostic hypothesis of the physicians in 50% of the cases (p 0.05), where 78.57% of the patients had surgical indication before computed tomography and 67.86% after computed tomography (p = 0.0546). The index of accurate diagnosis of computed tomography, when compared to the anatomopathologic examination and the final diagnosis, was observed in 82.14% of the cases (p = 0.013). When the analysis was done dividing the patients in surgical and nonsurgical group, were obtained an accuracy of 89.28% (p 0.0001). The difference of 7.2 days of hospitalization (p = 0.003) was obtained compared with the mean of the acute abdomen without use the computed tomography. Conclusion: The computed tomography is correlative with the anatomopathology and has great accuracy in the surgical indication, associated with the capacity of increase the confident index of the physicians, reduces the hospitalization time, reduces the number of surgeries and is cost-effective. (author)

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2007-04-15

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

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

    Energy Technology Data Exchange (ETDEWEB)

    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)

    2010-12-15

    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.)

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2012-09-15

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

  9. Dedicated breast computed tomography: Basic aspects

    Energy Technology Data Exchange (ETDEWEB)

    Sarno, Antonio; Mettivier, Giovanni, E-mail: mettivier@na.infn.it; Russo, Paolo [Dipartimento di Fisica, Università di Napoli Federico II, Via Cintia, Napoli I-80126, Italy and INFN Sezione di Napoli, Napoli I-80126 (Italy)

    2015-06-15

    X-ray mammography of the compressed breast is well recognized as the “gold standard” for early detection of breast cancer, but its performance is not ideal. One limitation of screening mammography is tissue superposition, particularly for dense breasts. Since 2001, several research groups in the USA and in the European Union have developed computed tomography (CT) systems with digital detector technology dedicated to x-ray imaging of the uncompressed breast (breast CT or BCT) for breast cancer screening and diagnosis. This CT technology—tracing back to initial studies in the 1970s—allows some of the limitations of mammography to be overcome, keeping the levels of radiation dose to the radiosensitive breast glandular tissue similar to that of two-view mammography for the same breast size and composition. This paper presents an evaluation of the research efforts carried out in the invention, development, and improvement of BCT with dedicated scanners with state-of-the-art technology, including initial steps toward commercialization, after more than a decade of R and D in the laboratory and/or in the clinic. The intended focus here is on the technological/engineering aspects of BCT and on outlining advantages and limitations as reported in the related literature. Prospects for future research in this field are discussed.

  10. Computed tomography studies on patients with mucopolysaccharidoses

    International Nuclear Information System (INIS)

    The appearances on computed tomography (CT) in eight patients with mucopolysaccharidosis Type I, two with mucopolysaccharidosis Type II and two with mucopolysaccharidosis Type IIIB are presented. Reference is also made to two further cases in which the CT showed special features. Follow-up scans were obtained to assess the evolution of the changes. The place of CT in the diagnosis of complications due to thecal involvement is examined. The density of grey matter on the CT scans was similar to that of normal brain. Inhaled xenon did not produce any special enhancement which could be helpful in assessing the degree of the mucopolysaccharide deposition within cerebral cells. Symmetrical low attenuation in the white matter was a very common finding. This work has shown that the stage in the evolution of the mucopolysaccharidoses at which hydrocephalus develops as a complication is highly variable and CSF diversion procedures are sometimes indicated to improve the quality of the patients' lives. These indications are briefly discussed. We consider that CT is essential for the adequate appraisal of these patients and to identify some treatable complications. (orig./MG)

  11. Radiation Doses from Computed tomography in Iraq

    International Nuclear Information System (INIS)

    Radiation doses to Patient during CT scanner and the radiological risk are significant. Patient dose survey has been conducted to investigate the Iraq patient radiation doses received in CT scanners in order to established reference dose levels. These doses are Entrance Surface Dose (ESD),computed tomography dose index(CTDI)), and dose length product (DLP). Two CT scanner were investigated in this study were, Siemens Somatom Plus 4, located in at medical city of Baghdad, and Philips, Optimus located in privet hospital at Baghdad. ESD were measured by TLD and Dosimax ionization chamber for head, chest, and abdomen for both sex and different weights. The TLD results were higher than that measured with Dosimax due to scattered radiation .The scattering factor which is the ratio between dose measured by TLD and that measured by ionization chamber range between (1.14-1.34) compare to international measurement which is range between (1.1-1.5).The (ESD) measured by the two methods were agree well after the subtraction of scattering dose, and have compered with original research. Dose profile were measured using array of TLD chips shows that its full width at half maximum is(7.99 mm) approximately equal the slice thickness(8 mm). Our results compare with reference level at U.K, European Guidelines and

  12. Quantitative investigations of megavoltage computed tomography

    Science.gov (United States)

    Rogers, Myron; Kerr, Andrew; Salomons, Greg; Schreiner, L. John

    2005-04-01

    Megavoltage computed tomography (MVCT) has been an active area of research and development in image guided radiation therapy. We have been investigating a particular implementation of MVCT in conjunction with studies of the potential for tomotherapy with a Cobalt-60 radiation source. In this paper, we present results comparing MVCT using a Co-60 source and a 4 MV linear accelerator to conventional kVCT imaging. The Co-60 and linac MVCT measurements were obtained with a first generation benchtop CT imager; the KVCT measurements were obtained using a Philips AcQSim CT Simulator). Phantoms containing various inserts ranging in density from air, through lung, soft tissue and bone equivalent materials and extending to high atomic number metals were imaged with the three modalities. The results enable characterization of image artifacts, CT number linearity and beam hardening. The MVCT images have sufficient contrast that soft tissue regions with 2.8% difference in electron density can be visualized. In MVCT, a linear relationship between CT numbers and electron densities extends to materials with Z ~ 60. In the 4MV CT imaging there is a position dependence of the CT numbers within a uniform water phantom, which is absent in Co-60 CT images, indicating the presence of beam hardening artifacts in the linac MVCT images. The differences between kVCT and MVCT will be discussed considering the variation of the photon interactions dominating the images. Our investigations indicate that MVCT has properties that may potentially extend its utility beyond radiation therapy.

  13. Radiation doses from computed tomography in Australia

    International Nuclear Information System (INIS)

    Recent surveys in various countries have shown that computed tomography (CT) is a significant and growing contributor to the radiation dose from diagnostic radiology. Australia, with 332 CT scanners (18 per million people), is well endowed with CT equipment compared to European countries (6 to 13 per million people). Only Japan, with 8500 units (78 per million people), has a significantly higher proportion of CT scanners. In view of this, a survey of CT facilities, frequency of examinations, techniques and patient doses has been performed in Australia. It is estimated that there are 1 million CT examinations in Australia each year, resulting in a collective effective dose of 7000 Sv and a per caput dose of 0.39 mSv. This per caput dose is much larger than found in earlier studies in the UK and New Zealand but is less than 0.48 mSv in Japan. Using the ICRP risk factors, radiation doses from CT could be inducing about 280 fatal cancers per year in Australia. CT is therefore a significant, if not the major, single contributor to radiation doses and possible risk from diagnostic radiology. (authors)

  14. Computed tomography findings in fibrosing mediastinitis

    Energy Technology Data Exchange (ETDEWEB)

    Devaraj, A. [Departments of Radiology, Royal Brompton Hospital, London (United Kingdom)]. E-mail: a.devaraj@rbht.nhs.uk; Griffin, N. [Department of Radiology, Chelsea and Westminster Hospital, London (United Kingdom); Nicholson, A.G. [Department of Histopathology, Royal Brompton Hospital, London (United Kingdom); Padley, S.P.G. [Departments of Radiology, Royal Brompton Hospital, London (United Kingdom)

    2007-08-15

    Aim: To describe the CT features of fibrosing mediastinitis. Materials and methods: The clinical notes, histology, and CT images from 12 patients with fibrosing mediastinitis were reviewed. Clinical data regarding the presentation and suspected aetiology were correlated with location of mediastinal disease, calcification, effect on mediastinal structures, and additional pulmonary findings on computed tomography (CT). Results: The mean age was 40.5 years, with seven female and five male patients. The most common presenting symptom was shortness of breath. Fibrosing mediastinitis diffusely infiltrated the mediastinum in five patients and was localized in seven. Calcification was present in two cases. Eleven of 12 cases had narrowing of mediastinal structures, including five with pulmonary artery narrowing, five with superior vena cava obstruction, four with bronchial narrowing, three with tracheal narrowing, and one with narrowing of the pulmonary vein. The disease was considered idiopathic in seven cases with a demonstrable aetiology in five cases. Eight out of 12 patients had additional pulmonary findings, including all patients with a known aetiology. Conclusions: In the present series of patients, fibrosing mediastinitis more commonly presented as a localized mediastinal mass than as diffuse mediastinal disease, with the anterior mediastinal compartment most frequently involved. Most cases were idiopathic compared with the majority of previous cases at this institution being ascribed to tuberculosis. There is a high incidence of concomitant pulmonary findings, in particular when an identifiable aetiology is present. Obstruction of vital structures frequently gives rise to complications.

  15. Intraperitoneal tuberculous abscess: computed tomography features

    Institute of Scientific and Technical Information of China (English)

    Peng; Dong; Jing-Jing; Chen; Xi-Zhen; Wang; Ya-Qin; Wang

    2015-01-01

    AIM: To evaluate the computed tomography(CT) features of intraperitoneal tuberculous abscess(IPTA). METHODS: Eight patients with IPTA confirmed by pathology were analyzed retrospectively. The clinical symptoms, medical images, and surgical findings were evaluated. Involvement of the intestine, peritoneum, viscera, and lymph nodes was also assessed. RESULTS: All 8 patients had a history of abdominal discomfort for 1 to 6 mo. Physical examination revealed a palpable abdominal mass in 6 patients. Three patients had no evidence of pulmonary tuberculosis(TB). All IPTAs(11 abscesses) were seen as a multiseptated, peripherally enhanced, hypodense mass with enlarged, rim-enhanced lymph nodes. The largest abscess diameter ranged from 4.5 cm to 12.2 cm. CT showed 2 types of IPTA: Lymph node fusion and encapsulation. Of the 8 patients, one had liver tuberculosis and one had splenic and ovarian tuberculosis. Two cases showed involvement of the terminal ileum and ileocecal junction. Ascites were found in 4 cases. Three patients had peritonitis and mesenteritis. Three patients showed involvement of the omentum. Three patients had histological evidence of caseating granuloma, and 5 had histological evidence of acid-fast bacilli. CONCLUSION: CT is crucial in the detection and characterization of IPTA. Certain CT findings are necessary for correct diagnosis.

  16. Application of computed tomography in paleoanthropological research

    Institute of Scientific and Technical Information of China (English)

    Xiujie Wu; Lynne A.Schepartz

    2009-01-01

    Hominin fossils are the most important materials for exploring questions about human origins and evolution. Because human fossils are very rare, it is impossible to use highly destructive techniques in order to study their morphology. Traditional analyses can only rely on the information gained from the study of the external morphology of specimens, and these approaches limited the study of human evolution. The application of computed tomography (CT) has facilitated major developments in paleoanthropology. To date, few studies on Chinese hominin fossils have used CT scanning methodology, but this is rapidly changing. In order to better understand the appli-cation of CT methodology in paleoanthropology, we review the applications of CT scanning on hominin fossils throughout the world.Studies examined include virtual fossil reconstruction, the use of endocasts to elucidate brain morphology, biomechanical analyses of bone distribution, imaging of mummies and research on early human health, and skeletal and dental microanatomical research.2009 National Natural Science Foundation of China and Chinese Academy of Sciences. Published by Elsevier Limited and Science in China Press. All rights reserved.

  17. A Detector for Proton Computed Tomography

    Energy Technology Data Exchange (ETDEWEB)

    Blazey, G.; et al.

    2013-12-06

    Radiation therapy is a widely recognized treatment for cancer. Energetic protons have distinct features that set them apart from photons and make them desirable for cancer therapy as well as medical imaging. The clinical interest in heavy ion therapy is due to the fact that ions deposit almost all of their energy in a sharp peak – the Bragg peak- at the very end of their path. Proton beams can be used to precisely localize a tumor and deliver an exact dose to the tumor with small doses to the surrounding tissue. Proton computed tomography (pCT) provides direct information on the location on the target tumor, and avoids position uncertainty caused by treatment planning based on imaging with X-ray CT. The pCT project goal is to measure and reconstruct the proton relative stopping power distribution directly in situ. To ensure the full advantage of cancer treatment with 200 MeV proton beams, pCT must be realized.

  18. Dose profile in computed tomography chest scan

    International Nuclear Information System (INIS)

    For the optimization of the patient dose in computed tomography (CT), the Brazilian legislation only established the diagnostic reference levels (DRL's) in terms of Multiple Scan Average Dose (MSAD) in a typical adult as a parameter of quality control of CT scanners. Conformity to the DRL's can be verified by measuring the dose distribution in CT scans and MSAD determination. An analysis of the quality of CT scans of the metropolitan region of Belo Horizonte is necessary by conducting pertinent tests to the study that are presented in the ANVISA (National Agency of Sanitary Vigilance) Guide. The purpose of this study is to investigate, in a chest scan, the variation of dose in CT. To measure the dose profile are used lithium fluoride thermoluminescent dosimeters (TLD-100 Rod) distributed in cylinders positioned in peripheral and central regions of a phantom of polymethylmethacrylate (PMMA). The data obtained allow us to observe the variation of the dose profile inside the phantom. The peripheral region shows higher dose values than the central region. The longitudinal variation can be observed and the maximum dose was recorded at the edges of the phantom (41,58±5,10) mGy at the midpoint of the longitudinal axis. The results will contribute to disseminate the proper procedure and optimize the dosimetry and the tests of quality control in CT, as well as make a critical analysis of the DRL's. (author)

  19. Portable Digital Radiography and Computed Tomography Manual

    Energy Technology Data Exchange (ETDEWEB)

    2007-11-01

    This user manual describes the function and use of the portable digital radiography and computed tomography (DRCT) scanner. The manual gives a general overview of x-ray imaging systems along with a description of the DRCT system. An inventory of the all the system components, organized by shipping container, is also included. In addition, detailed, step-by-step procedures are provided for all of the exercises necessary for a novice user to successfully collect digital radiographs and tomographic images of an object, including instructions on system assembly and detector calibration and system alignment. There is also a short section covering the limited system care and maintenance needs. Descriptions of the included software packages, the DRCT Digital Imager used for system operation, and the DRCT Image Processing Interface used for image viewing and tomographic data reconstruction are given in the appendixes. The appendixes also include a cheat sheet for more experienced users, a listing of known system problems and how to mitigate them, and an inventory check-off sheet suitable for copying and including with the machine for shipment purposes.

  20. Computed tomography in acute ischemic stroke

    Energy Technology Data Exchange (ETDEWEB)

    Loevblad, Karl-Olof [HUG-Geneva University Hospital, Geneva University Medical School, Department of Neuroradiology, Department of Imaging and Medical Informatics, Geneva (Switzerland); Baird, Alison E. [SUNY Downstate Medical Center, Cerebrovascular Disease and Stroke, 450 Clarkson Avenue, Box 1213, Brooklyn, NY (United States)

    2010-03-15

    Stroke remains the third most important cause of mortality in industrialized countries; this has prompted research for improvements in both diagnostic and therapeutic strategies for patients with signs of acute cerebral ischemia. Over the last decade, there has been a parallel in progress in techniques in both diagnostic and therapeutic options. While previously only used for excluding hemorrhage, imaging now has the possibility to detect ischemia, vascular occlusion, as well as detect tissue at risk in one setting. It should also allow to monitor treatment and predict/exclude therapeutic complications. Parallel to advances in magnetic resonance imaging of stroke, computed tomography has improved immensely over the last decade due to the development of CT scanners that are faster and that allow to acquire studies such as CT perfusion or CT angiography in a reliable way. CT can detect many signs that might help us detect impending signs of massive infarction, but we still lack the experience to use these alone to prevent a patient from benefitting from possible therapy. (orig.)

  1. Computed tomography and magnetic resonance colonography

    International Nuclear Information System (INIS)

    Colon cancer is the second leading cause of cancer death in the western world. Adenomatous colorectal polyps, which are found in 30-50% of Americans more than 50 years old, are recognized as important precursors of malignancy. Probably most of the invasive colon carcinomas arise from polyps. For this reason an early detection of these polyps and their complete removal is a recognized strategy for the prevention of colon cancer. So far no single method for an early diagnois of colon polyps or colon cancer offers high sensitivity and specificity along with low cost and good patient accccf Endo-opic colonoscopy allows the accurate detection of very small lesions and has since almost completely replaced fluooscopy. Cross-sectional imaging techniques, including magnetic resonance imaging (MRI) and computed tomography (CT), are increasingly being considered imaging modalities for the detection of colorectal polyps. CT and MR colonography are new techniques for imaging of the colon. In symptomatic patients, these new techniques show promising results for the detection of polyps equal to or larger than 1 cm in diameter. (author)

  2. Computed tomography imaging and angiography - principles.

    Science.gov (United States)

    Kamalian, Shervin; Lev, Michael H; Gupta, Rajiv

    2016-01-01

    The evaluation of patients with diverse neurologic disorders was forever changed in the summer of 1973, when the first commercial computed tomography (CT) scanners were introduced. Until then, the detection and characterization of intracranial or spinal lesions could only be inferred by limited spatial resolution radioisotope scans, or by the patterns of tissue and vascular displacement on invasive pneumoencaphalography and direct carotid puncture catheter arteriography. Even the earliest-generation CT scanners - which required tens of minutes for the acquisition and reconstruction of low-resolution images (128×128 matrix) - could, based on density, noninvasively distinguish infarct, hemorrhage, and other mass lesions with unprecedented accuracy. Iodinated, intravenous contrast added further sensitivity and specificity in regions of blood-brain barrier breakdown. The advent of rapid multidetector row CT scanning in the early 1990s created renewed enthusiasm for CT, with CT angiography largely replacing direct catheter angiography. More recently, iterative reconstruction postprocessing techniques have made possible high spatial resolution, reduced noise, very low radiation dose CT scanning. The speed, spatial resolution, contrast resolution, and low radiation dose capability of present-day scanners have also facilitated dual-energy imaging which, like magnetic resonance imaging, for the first time, has allowed tissue-specific CT imaging characterization of intracranial pathology. PMID:27432657

  3. REVIEW: X-ray computed tomography

    Science.gov (United States)

    Kalender, Willi A.

    2006-07-01

    X-ray computed tomography (CT), introduced into clinical practice in 1972, was the first of the modern slice-imaging modalities. To reconstruct images mathematically from measured data and to display and to archive them in digital form was a novelty then and is commonplace today. CT has shown a steady upward trend with respect to technology, performance and clinical use independent of predictions and expert assessments which forecast in the 1980s that it would be completely replaced by magnetic resonance imaging. CT not only survived but exhibited a true renaissance due to the introduction of spiral scanning which meant the transition from slice-by-slice imaging to true volume imaging. Complemented by the introduction of array detector technology in the 1990s, CT today allows imaging of whole organs or the whole body in 5 to 20 s with sub-millimetre isotropic resolution. This review of CT will proceed in chronological order focussing on technology, image quality and clinical applications. In its final part it will also briefly allude to novel uses of CT such as dual-source CT, C-arm flat-panel-detector CT and micro-CT. At present CT possibly exhibits a higher innovation rate than ever before. In consequence the topical and most recent developments will receive the greatest attention.

  4. Computed tomography experiments of Pantex high explosives

    Science.gov (United States)

    Perkins, D. E.; Martz, H. E.; Hester, L. O.; Sobczak, G.; Pratt, C. L.

    1992-04-01

    X-ray computed tomography is an advanced imaging technique which provide three-dimensional nondestructive characterization of materials, components and assemblies. The CT Project group at Lawrence Livermore National Laboratory (LLNL) and the Pantex Plant are cooperating to examine the use of CT technology to inspect and characterize high-explosives pressings (e.g., PBX-9502, LX-10-2). High-explosives pressings manufactured by Pantex must be characterized prior to assembling into weapons systems; a nondestructive examination of all assembly parts would be preferable to the current sampling and destructive testing. The earlier in the processing cycle this can be done the more cost effective it will be. We have performed experiments that show that this characterization can be performed at the pressed billet stage using CT. We have detected 2-mm inclusions in a 15-cm diameter billet and 3.5-mm voids in a 20-cm diameter billet. Based on these results we show calculations that can be used to design production CT systems for characterization of high-explosives.

  5. Perfusion computed tomography in renal cell carcinoma

    Institute of Scientific and Technical Information of China (English)

    Chandan; J; Das; Usha; Thingujam; Ananya; Panda; Sanjay; Sharma; Arun; Kumar; Gupta

    2015-01-01

    Various imaging modalities are available for the diagnosis, staging and response evaluation of patients with renal cell carcinoma(RCC). While contrast enhanced computed tomography(CT) is used as the standard of imaging for size, morphological evaluation and response assessment in RCC, a new functional imaging technique like perfusion CT(p CT), goes down to the molecular level and provides new perspectives in imaging of RCC. p CT depicts regional tumor perfusion and vascular permeability which are indirect parameters of tumor angiogenesis and thereby provides vital information regarding tumor microenvironment. Also response evaluation using p CT may predate the size criteria used in Response Evaluation Criteria in Solid Tumors, as changes in the perfusion occurs earlier following tissue kinase inhibitors before any actual change in size. This may potentially help in predicting prognosis, better selection of therapy and more accurate and better response evaluation in patients with RCC. This article describes the techniques and role of p CT in staging and response assessment in patients with RCCs.

  6. Radiation doses from computed tomography in Australia

    Energy Technology Data Exchange (ETDEWEB)

    Thomson, J.E.M.; Tingey, D.R.C

    1997-11-01

    Recent surveys in various countries have shown that computed tomography (CT) is a significant and growing contributor to the radiation dose from diagnostic radiology. Australia, with 332 CT scanners (18 per million people), is well endowed with CT equipment compared to European countries (6 to 13 per million people). Only Japan, with 8500 units (78 per million people), has a significantly higher proportion of CT scanners. In view of this, a survey of CT facilities, frequency of examinations, techniques and patient doses has been performed in Australia. It is estimated that there are 1 million CT examinations in Australia each year, resulting in a collective effective dose of 7000 Sv and a per caput dose of 0.39 mSv. This per caput dose is much larger than found in earlier studies in the UK and New Zealand but is less than 0.48 mSv in Japan. Using the ICRP risk factors, radiation doses from CT could be inducing about 280 fatal cancers per year in Australia. CT is therefore a significant, if not the major, single contributor to radiation doses and possible risk from diagnostic radiology. (authors) 28 refs., 11 tabs., 10 figs.

  7. Computed tomography findings in pancreas divisum

    International Nuclear Information System (INIS)

    In 29 patients with abdominal pain the diagnosis of pancreas divisum (PD) was verified by endoscopic retrograde pancreatography (EPR) via both the major and the minor papilla. Computed tomography (CT) was done in all patients to evaluate contour, volume, antero-posterior diameters and attenuation values of the gland in comparison with a normal reference series. Also, the validity of the CT grading of pancreatitis was assessed in comparison with ERP grading. Patients with PD had an increased cranio-caudal diameter of the pancreatic head (p<0.001). Further, the main pancreatic duct was visualized more often in patients with PD (p<0.01), who also had an increasing frequency of pancreatic calcifications (p<0.05). Otherwise there were no differences compared with the normal series. The observed reduction in the volume of the gland in patients with marked pancreatitis at ERP seemingly reflected the severity of inflammation. No cleavage between the dorsal and ventral anlage was identified. CT was found to be too unspecific to be of any use in grading of pancreatitis. In conclusion, CT findings in patients with PD are sparse, unspecific and preferably a reflection of pancreatitis, if present. ERP remains the ''gold standard'' for the diagnosis. (orig.)

  8. Relevance of computed tomography in gynecological tumors

    Energy Technology Data Exchange (ETDEWEB)

    Hagemann, J.R.; Hagemann, J.

    1983-11-01

    1. Abdominal CT examination is the method of choice when examining ovarial tumours. 2. Abdominal CT is redundant in the early stages of carcinoma of the collum and if the carcinoma has penetrated into the vagina. 3. In advanced stages of carcinoma of the collum, CT enables accurate staging. CT is at least equal in relevance to gynecological examination in respect of assessment of parametraneous infiltration. Distant metastases, as well as complications of the efferent urinary tract can be visualized. In view of this, the following procedure appears meaningful in advanced carcinoma of the collum: First of all, gynecological examination is performed without anaesthesia to confirm the findings in the regions of the portio and vagina; as far as possible, the existence of the central parametraneous infiltrations is confirmed. For the purpose of further staging of the parametraneous infiltration, as well as of the paraaortal lymphomas and possible metastases, as well as for the purpose of excluding hydronephrosis, computed tomography is performed. This avoids burdening the patient with an examination under anaesthesia, and it also avoids invasive examination methods, such as urography and lymphography.

  9. Relevance of computed tomography in gynaecological tumors

    International Nuclear Information System (INIS)

    1. Abdominal CT examination is the method of choice when examining ovarial tumours. 2. Abdominal CT is redundant in the early stages of carcinoma of the collum and if the carcinoma has penetrated into the vagina. 3. In advanced stages of carcinoma of the collum, CT enables accurate staging. CT is at least equal in relevance to gynaecological examination in respect of assessment of parametraneous infiltration. Distant metastases, as well as complications of the efferent urinary tract can be visualized. In view of this, the following procedure appears meaningful in advanced carcinoma of the collum: First of all, gynaecological examination is performed without anaesthesia to confirm the findings in the regions of the portio and vagina; as far as possible, the existence of the central parametraneous infiltrations is confirmed. For the purpose of further staging of the parametraneous infiltration, as well as of the paraaortal lymphomas and possible metastases, as well as for the purpose of excluding hydronephrosis, computed tomography is performed. This avoids burdening the patient with an examination under anaesthesia, and it also avoids invasive examination methods, such as urography and lymphography. (orig.)

  10. Dynamic X-ray computed tomography

    International Nuclear Information System (INIS)

    Paper Dynamic computed tomography (CT) imaging aims at reconstructing image sequences where the dynamic nature of the living human body is of primary interest. Main concerned applications are image-guided interventional procedures, functional studies and cardiac imaging. The introduction of ultra-fast rotating gantries along with multi-row detectors and in near future area detectors allows a huge progress toward the imaging of moving organs with low-contrast resolution. This paper gives an overview of the different concepts used in dynamic CT. A new reconstruction algorithm based on a voxel-specific dynamic evolution compensation is also presented. It provides four-dimensional image sequences with accurate spatio-temporal information, where each frame is reconstructed using a long-scan acquisition mode on several half-turns. In the same time, this technique permits to reduce the dose delivered per rotation while keeping the same signal to noise ratio for every frame using an adaptive motion-compensated temporal averaging. Results are illustrated on simulated data. (authors)

  11. Ruptured ectopic pregnancy diagnosed with computed tomography

    International Nuclear Information System (INIS)

    The rupture of ectopic pregnancy (EP) still remains the primary and direct cause of death in the first trimester of pregnancy. Ultrasonography is known to be a modality of choice in EP diagnostics. We found a severe discrepancy between the frequency of ectopic pregnancies (EP) and the number of available computed tomography (CT) examinations. A 29-year-old woman was admitted to the emergency department with a history of abdominal pain, nausea, vomiting and collapse. Sonographic findings of a suspected EP were unclear. Moreover, not all features of intrauterine pregnancy were present. Due to the patient’s life-threatening condition, an emergency multi-slice CT with MPR and VRT reconstructions was performed, revealing symptoms of a ruptured EP. In the right adnexal area, a well-vascularized, solid-cystic abnormal mass lesion was found. Intraperitoneal hemorrhage was confirmed intraoperatively, and the right fallopian tube with a tubal EP was resected. In the surgery in situ, as well as in the pathological examination of the tumor mass, a human embryo of approximately 1.5 cm in length (beginning of the 8th week of gestation) was found. Although ultrasonography still remains the first-line imaging examination in EP diagnostics, sometimes the findings of suspected EPs are unclear and not sufficient. The rupture of EP, with serious bleeding and symptoms of shock, may require an emergent pelvic and abdominal CT inspection. A clear correlation was found between the macroscopic CT images and the intraoperatively sampled material

  12. Computed Tomography Following Body Stuffing Heroin

    Directory of Open Access Journals (Sweden)

    Sean P. Nordt

    2015-12-01

    Full Text Available A 37-year-old male presented to the emergency department (ED in police custody for “medical clearance” before being taken to jail. The patient was approached by police officers for suspicion of selling illicit drugs. When approached by police he ran away and was witnessed to swallow several small plastic baggies suspected to contain heroin. He was apprehended and brought to the ED. On arrival, he was asymptomatic with a blood pressure 144/83mmHg, heart rate 67bpm, respiratory rate of 19bpm, oxygen saturation of 99% on room air and afebrile. A Glasgow coma score was 15 and he was alert and oriented to person, place and time. Patient had a negative review of systems. On physical examination pupils were 4mm and reactive to light, lungs clear to auscultation and had normal respiratory rate with normal cardiovascular exam. Abdomen was soft, non-tender and non-distended with present bowel sounds. The patient admitted to ingesting approximately 20 packets of heroin to avoid being charged with possession. The patient declined activated charcoal and whole bowel irrigation (WBI with polyethylene glycol-electrolyte solution (PEG-ELS. The patient declined a urine toxicology immunoassay screen. A computed tomography (CT of his abdomen with contrast was obtained and read as normal except for a cluster of foreign bodies within the distal stomach likely contained within a plastic bag.

  13. Computed tomography characterisation of additive manufacturing materials.

    Science.gov (United States)

    Bibb, Richard; Thompson, Darren; Winder, John

    2011-06-01

    Additive manufacturing, covering processes frequently referred to as rapid prototyping and rapid manufacturing, provides new opportunities in the manufacture of highly complex and custom-fitting medical devices and products. Whilst many medical applications of AM have been explored and physical properties of the resulting parts have been studied, the characterisation of AM materials in computed tomography has not been explored. The aim of this study was to determine the CT number of commonly used AM materials. There are many potential applications of the information resulting from this study in the design and manufacture of wearable medical devices, implants, prostheses and medical imaging test phantoms. A selection of 19 AM material samples were CT scanned and the resultant images analysed to ascertain the materials' CT number and appearance in the images. It was found that some AM materials have CT numbers very similar to human tissues, FDM, SLA and SLS produce samples that appear uniform on CT images and that 3D printed materials show a variation in internal structure.

  14. Computed tomography with selectable image resolution

    International Nuclear Information System (INIS)

    A computed tomography system x-ray detector has a central group of half-width detector elements and groups of full-width elements on each side of the central group. To obtain x-ray attenuation data for whole body layers, the half-width elements are switched effectively into paralleled pairs so all elements act like full-width elements and an image of normal resolution is obtained. For narrower head layers, the elements in the central group are used as half-width elements so resolution which is twice as great as normal is obtained. The central group is also used in the half-width mode and the outside groups are used in the full-width mode to obtain a high resolution image of a body zone within a full body layer. In one embodiment data signals from the detector are switched by electronic multiplexing and in another embodiment a processor chooses the signals for the various kinds of images that are to be reconstructed. (author)

  15. Acute Calculous Cholecystitis Missed on Computed Tomography and Ultrasound but Diagnosed with Fluorodeoxyglucose-Positron Emission Tomography/Computed Tomography

    Directory of Open Access Journals (Sweden)

    Carina Mari Aparici

    2016-01-01

    Full Text Available We present a case of a 69-year-old patient who underwent ascending aortic aneurysm repair with aortic valve replacement. On postsurgical day 12, he developed leukocytosis and low-grade fevers. The chest computed tomography (CT showed a periaortic hematoma which represents a postsurgical change from aortic aneurysm repair, and a small pericardial effusion. The abdominal ultrasound showed cholelithiasis without any sign of cholecystitis. Finally, a fluorodeoxyglucose (FDG-positron emission tomography (PET/CT examination was ordered to find the cause of fever of unknown origin, and it showed increased FDG uptake in the gallbladder wall, with no uptake in the lumen. FDG-PET/CT can diagnose acute cholecystitis in patients with nonspecific clinical symptoms and laboratory results.

  16. Acute Calculous Cholecystitis Missed on Computed Tomography and Ultrasound but Diagnosed with Fluorodeoxyglucose-Positron Emission Tomography/Computed Tomography.

    Science.gov (United States)

    Aparici, Carina Mari; Win, Aung Zaw

    2016-01-01

    We present a case of a 69-year-old patient who underwent ascending aortic aneurysm repair with aortic valve replacement. On postsurgical day 12, he developed leukocytosis and low-grade fevers. The chest computed tomography (CT) showed a periaortic hematoma which represents a postsurgical change from aortic aneurysm repair, and a small pericardial effusion. The abdominal ultrasound showed cholelithiasis without any sign of cholecystitis. Finally, a fluorodeoxyglucose (FDG)-positron emission tomography (PET)/CT examination was ordered to find the cause of fever of unknown origin, and it showed increased FDG uptake in the gallbladder wall, with no uptake in the lumen. FDG-PET/CT can diagnose acute cholecystitis in patients with nonspecific clinical symptoms and laboratory results. PMID:27625897

  17. Abdominal alterations in disseminated paracoccidioidomycosis: computed tomography findings

    Energy Technology Data Exchange (ETDEWEB)

    Vermelho, Marli Batista Fernandes; Correia, Ademir Silva; Michailowsky, Tania Cibele de Almeida; Suzart, Elizete Kazumi Kuniyoshi; Ibanes, Aline Santos; Almeida, Lanamar Aparecida; Khoury, Zarifa; Barba, Mario Flores, E-mail: marlivermelho@globo.com [Instituto de Infectologia Emilio Ribas (IIER), Sao Paulo, SP (Brazil)

    2015-03-15

    Objective: to evaluate the incidence and spectrum of abdominal computed tomography imaging findings in patients with paracoccidioidomycosis. Materials and methods: retrospective analysis of abdominal computed tomography images of 26 patients with disseminated paracoccidioidomycosis. Results: abnormal abdominal tomographic findings were observed in 18 patients (69.2%), while no significant finding was observed in the other 8 (30.8%) patients. Conclusion: computed tomography has demonstrated to play a relevant role in the screening and detection of abdominal abnormalities in patients with disseminated paracoccidioidomycosis. (author)

  18. Diffuse abnormalities of the trachea: computed tomography findings

    Energy Technology Data Exchange (ETDEWEB)

    Marchiori, Edson [Universidade Federal Fluminense (UFF), Niteroi, RJ (Brazil). Dept. de Radiologia]. E-mail: edmarchiori@gmail.com; Pozes, Aline Serfaty [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Faculdade de Medicina. Dept. de Radiologia; Souza Junior, Arthur Soares [Faculdade de Medicina de Sao Jose do Rio Preto (FAMERP), SP (Brazil). Escola de Medicina. Dept. de Radiologia; Escuissato, Dante Luiz [Universidade Federal do Parana (UFPR), Curitiba, PR (Brazil). Dept. de Radiologia; Irion, Klaus Loureiro [The Cardiothoracic Centre NHS Trust, Liverpool (United Kingdom); Araujo Neto, Cesar de [Universidade Federal da Bahia (UFBA), Salvador, BA (Brazil). Dept. de Radiologia; Barillo, Jorge Luiz; Zanetti, Glaucia [Faculdade de Medicina de Petropolis (FMP), RJ (Brazil). Dept. de Cirurgia Clinica; Souza, Carolina Althoff [University of Ottawa, Ottawa, ON (Canada)

    2008-01-15

    The aim of this pictorial essay was to present the main computed tomography findings seen in diffuse diseases of the trachea. The diseases studied included amyloidosis, tracheobronchopathia osteochondroplastica, tracheobronchomegaly, laryngotracheobronchial papillomatosis, lymphoma, neurofibromatosis, relapsing polychondritis, Wegener's granulomatosis, tuberculosis, paracoccidioidomycosis, and tracheobronchomalacia. The most common computed tomography finding was thickening of the walls of the trachea, with or without nodules, parietal calcifications, or involvement of the posterior wall. Although computed tomography allows the detection and characterization of diseases of the central airways, and the correlation with clinical data reduces the diagnostic possibilities, bronchoscopy with biopsy remains the most useful procedure for the diagnosis of diffuse lesions of the trachea. (author)

  19. Abdominal alterations in disseminated paracoccidioidomycosis: computed tomography findings

    International Nuclear Information System (INIS)

    Objective: to evaluate the incidence and spectrum of abdominal computed tomography imaging findings in patients with paracoccidioidomycosis. Materials and methods: retrospective analysis of abdominal computed tomography images of 26 patients with disseminated paracoccidioidomycosis. Results: abnormal abdominal tomographic findings were observed in 18 patients (69.2%), while no significant finding was observed in the other 8 (30.8%) patients. Conclusion: computed tomography has demonstrated to play a relevant role in the screening and detection of abdominal abnormalities in patients with disseminated paracoccidioidomycosis. (author)

  20. Diagnosis of hoof disease in horses using computed tomography

    Directory of Open Access Journals (Sweden)

    Kovač Milomir

    2002-01-01

    Full Text Available This study describes findings of computed tomography investigations at the Bergische Equine Clinic (Germany of 39 horses with hoof diseaseas. The most frequently findings were the navicular syndrome (eight horses, laminitis (seven horses, keratnoma (six horses and ossification of collateral cartilages in the distal phalanx (four horses. The special value of the computed tomography is in evaluating the size and courses fracture/fissure of the navicular and koffin bones, which were diagnose in five horses. In four of horses no pathologic changes of the hoof were determined by computed tomography.

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

    DEFF Research Database (Denmark)

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

    2013-01-01

    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...

  2. Positron emission tomography/computed tomography for optimized colon cancer staging and follow up

    DEFF Research Database (Denmark)

    Engelmann, Bodil Elisabeth; Loft, Annika; Kjær, Andreas;

    2014-01-01

    OBJECTIVES: Optimal management of colon cancer (CC) requires detailed assessment of extent of disease. This study prospectively investigates the diagnostic accuracy of 2-deoxy-2-[18F]fluoro-D-glucose positron emission tomography/computed tomography (PET/CT) for staging and detection of recurrence...

  3. Positron emission tomography-computed tomography has a clinical impact for patients with cervical cancer

    DEFF Research Database (Denmark)

    Sandvik, Rikke Mulvad; Jensen, Pernille Tine; Hendel, Helle Westergren;

    2011-01-01

    Many studies have found that positron emission tomography-computed tomography (PET-CT) has a high sensitivity and specificity in the identification of metastasis in cervical cancer. Herlev Hospital, Denmark, has been performing PET-CTs in stage I-IV cervical cancer since 1 May 2006. The present s...

  4. Fluorine-18 fluorodeoxyglucose positron emission tomography-computed tomography in evaluation of residual intramuscular myxoma

    International Nuclear Information System (INIS)

    Intramuscular myxoma (IM) is a rare benign neoplasm. In a patient diagnosed with IM of left thigh, we report the utility of a postoperative fluorine-18 fluorodeoxyglucose positron emission tomography-computed tomography scan in assessing the efficacy of surgical excision

  5. Positron emission tomography-computed tomography has a clinical impact for patients with cervical cancer

    DEFF Research Database (Denmark)

    Sandvik, Rikke Mulvad; Jensen, Pernille Tine; Hendel, Helle W;

    2011-01-01

    Many studies have found that positron emission tomography-computed tomography (PET-CT) has a high sensitivity and specificity in the identification of metastasis in cervical cancer. Herlev Hospital, Denmark, has been performing PET-CTs in stage I-IV cervical cancer since 1 May 2006. The present...

  6. The Use of GPUs for Solving the Computed Tomography Problem

    Directory of Open Access Journals (Sweden)

    A.E. Kovtanyuk

    2014-07-01

    Full Text Available Computed tomography (CT is a widespread method used to study the internal structure of objects. The method has applications in medicine, industry and other fields of human activity. In particular, Electronic Imaging, as a species CT, can be used to restore the structure of nanosized objects. Accurate and rapid results are in high demand in modern science. However, there are computational limitations that bound the possible usefulness of CT. On the other hand, the introduction of high-performance calculations using Graphics Processing Units (GPUs provides improving quality and performance of computed tomography investigations. Moreover, parallel computing with GPUs gives significantly higher computation speeds when compared with (Central Processing Units CPUs, because of architectural advantages of the former. In this paper a computed tomography method of recovering the image using parallel computations powered by NVIDIA CUDA technology is considered. The implementation of this approach significantly reduces the required time for solving the CT problem.

  7. Computed Tomography diagnosis of skeletal involvement in multiple myeloma

    International Nuclear Information System (INIS)

    The authors assess the role of Computed Topography in the diagnosis and management of multiple myeloma (MM) and investigate if Computed Tomography findings can influence the clinical approach, prognosis and treatment. 273 multiple myeloma patients submitted to Computed Tomography June 1994, to December, 1996. The patients were 143 men and 130 women (mean age: 65 years): 143 were stage I, 38 stage II and 92 stage III according to Durie and Salomon's clinical classification. All patients were submitted to blood tests, spinal radiography and Computed Tomography, the latter with serial 5-mm scans on several vertebral bodies. Computed Tomography despicted vertebral arch and process involvement in 3 cases with the vertebral pedicle sign. Moreover, Computed Tomography proved superior to radiography in showing the spread of myelomatous masses into the soft tissues in a case with solitary permeative lesion in the left public bone, which facilitated subsequent biopsy. As for extraosseous localizations, Computed Tomography demonstrated thoracic soft tissue (1 woman) and pelvic (1 man) involvement by myelomtous masses penetrating into surrounding tissues. In our series, only a case of osteosclerotic bone myeloma was observed in the pelvis, associated with lytic abnormalities. Computed Tomography findings do not seem to improve the clinical approach and therapeutic management of the disease. Nevertheless, the authors reccommend Computed Tomography for some myelomatous conditions, namely: a) in the patients with focal bone pain but normal skeletal radiographs; b) in the patients with M protein, bone marrow plasmocytosis and back pain, but with an incoclusive multiple myeloma diagnosis; c) to asses bone spread in the regions which are anatomically complex or difficult to study with radiography and to depict soft tissue involvement; d) for bone biopsy

  8. Dose modulated computed tomography automated dosimetry

    International Nuclear Information System (INIS)

    Full text: Computed Tomography (CT) scans contribute a significant portion of the effective radiation dose from medical procedures and generally large effective radiation doses per diagnostic examination. With the advent of Multislice CT, the potential for large radiation exposures increased. This combined with the appeal of the resultant isotropic imaging and the increasing number of applications for which CT could be utilised (including screening procedures) has further increased the need for vigilant monitoring of CT protocols and use with respect to radiation dose. The introduction of dose modulated Computed Tomography has proven an effective method for reducing patient dose and is now widely used by CT manufacturers. This involves lowering the mA when scanning through anatomical regions which do not require a large mA. Many CT investigations now utilise dose modulation. Some of these studies will include over 900 images for which the mA and occasionally other factors could vary. In order to utilise the existing software to perform CT dosimetry a program has been written to automatically extract scan parameters from CT dicom image files and apply the ImPACT CT Patient Dosimetry Calculator, for slices with differing factors. Matlab has been used to write and compile a program which sorts through a folder of dicom images and extracts the appropriate dicom header information. Some manufacturers store different series and reformatted images all within the same folder. The images of the CT study for which the dosimetry is to be performed must be stored within the one folder and must be in a dicom format. The program has been written to accommodate several manufacturers, which all contain different information in their dicom headers. The Matlab program groups the various study/image types, extracting the relevant dicom header information, which is written to an Excel worksheet. An Excel file uses this information to run the ImPACT CT Patient Dosimetry Calculator with

  9. Time Domain Terahertz Axial Computed Tomography Non Destructive Evaluation Project

    Data.gov (United States)

    National Aeronautics and Space Administration — In this Phase 2 project, we propose to develop, construct, and deliver to NASA a computed axial tomography time-domain terahertz (CT TD-THz) non destructive...

  10. Time Domain Terahertz Axial Computed Tomography Non Destructive Evaluation Project

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose to demonstrate key elements of feasibility for a high speed automated time domain terahertz computed axial tomography (TD-THz CT) non destructive...

  11. Computed tomography of diffuse pulmonary diseases

    International Nuclear Information System (INIS)

    This article summarizes our preliminary results on high resolution computed tomography of 101 patients with various diffuse lung diseases. Instead of pattern recognition routinely done on chest radiogram (nodular, reticular or reticulo-nodular) we emphasized the relation of the lesions with inherent structures of the lung seen on the CT images. For this purpose our ten years radiologic-pathologic correlation on inflated and fixed lung specimens proved quite useful. 1) Centrilobular inflammatory nodules. This was seen in diffuse panbronchiolitis (DPB), allergic broncho-pulmonary aspergillosis, tuberculosis, pneumoconiosis and lobular pneumonia. DPB and bronchogenic spread of tuberculosis were most representative. The nodules produced by these diseases were located at the extreme end of bronchial branchings and separated by 2 to 3 mm from the pleura and pulmonary vein which constitute the edge of the secondary pulmonary lobule. 2) The lesions extending along bronchoarterial sheath and pulmonary vein. The contours of the pulmonary vessels were irregular and their calibers enlarged. These findings were seen in sarcoidosis and lymphangiosis carcinomatosa. 3) Lobular and multilobular lesions. This was seen in diffuse interstitial pneumonia and in alveolar filling diseases. The margins of the lesions were straight or curved slightly suggesting that disease is blocked by the lobular septa. Fine air bronchogram within the lesions was characteristic in chronic interstitial pneumonia. 4) Slight to moderate increase of lung density with multilobular distribution. This was seen in interstitial pneumonia, sarcoidosis and hypersensitivity pneumonitis. We supposed that this finding corresponds to cellular or fibrous thickening of alveolar septa, but direct proof was not available. (J.P.N.)

  12. Computed tomography in Duchenne type muscular dystrophy

    International Nuclear Information System (INIS)

    The computed tomography (CT) scan was performed on 91 Duchenne type muscular dystrophy (DMD) patients on the following four levels; (1) at the level of L3 vertebra, (2) 2-3cm above the symphysis pubica, (3) midposition of the thigh, (4) largest-diameter section of the lower leg. The CT of muscles common to most of the DMD patients were as follows: 1. Muscle atrophy: Muscle atrophy was shown as a reduction in the cross-sectional area of the muscles. Very mild muscle atrophy could be detected either by the clearly identified muscle border or by scattered low-density areas of so-called ''moth-eaten'' appearance within muscles. 2. Fat infiltration: The decrease in radio-density of muscles was interpreted as infiltration of fatty tissue. This type of density change was further classified into diffuse, streaked, cobblestone and salt-and-pepper patterns according to the spacial distribution of low-density areas. 3. Selectivity pattern: As the chronological sequence of DMD muscle degeneration is usually different among individual muscles, it may be seen, in some stages, that some of the synergistic muscles are still only slightly involved, while the others are quite severely atrophied with evident fat infiltration. In certain stages of the disease, most of the patients show relative preservation of particular muscles although they assumed a rounded shape. The most resistent muscle was musculus gracilis, followed by the musculus sartorius, musculus semitendinosus (and/or musculus semimembranosus) in that order. According to the severity of the CT changes, 86 of the 91 patients were classed into five stages from A1 to A5. Morphological stages (A1-A5) were well correlated to the functional disability stages by Ueda with a correlation factor of r=0.88. (J.P.N.)

  13. Characterization of HPGe detectors using Computed Tomography

    Energy Technology Data Exchange (ETDEWEB)

    Hedman, A., E-mail: Angelica.Hedman@foi.se [Swedish Defence Research Agency, Division of CBRN Defence and Security, SE-90182 Umeå (Sweden); Umeå University, Department of Radiation Sciences, Radiation Physics, SE-90187 Umeå (Sweden); Bahar Gogani, J.; Granström, M. [Swedish Defence Research Agency, Division of CBRN Defence and Security, SE-90182 Umeå (Sweden); Johansson, L.; Andersson, J.S. [Umeå University, Department of Radiation Sciences, Radiation Physics, SE-90187 Umeå (Sweden); Ramebäck, H. [Swedish Defence Research Agency, Division of CBRN Defence and Security, SE-90182 Umeå (Sweden); Chalmers University of Technology, Department of Chemical and Biological Engineering, Nuclear Chemistry, SE-41296 Göteborg (Sweden)

    2015-06-11

    Computed Tomography (CT) high-resolution imaging have been used to investigate if there is a significant change in the crystal-to-window distance, i.e. the air gap thickness, in a small n-type detector cooled to 77 K, and in a medium sized p-type HPGe detector when cooled to 100 K. The findings were compared to detector dimension data made available by the manufacturer. The air gap thickness increased by (0.38±0.07) mm for the n-type detector and by (0.40±0.15) mm for the p-type detector when the detectors were cooled to 77 resp. 100 K compared to at room temperature. Monte Carlo calculations indicate that these differences have a significant impact on the efficiency in close geometries (<5 cm). In the energy range of 40–700 keV with a source placed directly on endcap, the change in detector efficiency with temperature is 1.9–2.9% for the n-type detector and 0.3–2.1% for the p-type detector. The measured air gap thickness when cooling the detector was 1.1 mm thicker than manufacturer data for the n-type detector and 0.2 mm thicker for the p-type detector. In the energy range of 40–700 keV and with a source on endcap, this result in a change in detector efficiency of 5.2–7.1% for the n-type detector and 0.2–1.0% for the p-type detector, i.e. the detector efficiency is overestimated using data available by the manufacturer.

  14. Dose in x-ray computed tomography.

    Science.gov (United States)

    Kalender, Willi A

    2014-02-01

    Radiation dose in x-ray computed tomography (CT) has become a topic of high interest due to the increasing numbers of CT examinations performed worldwide. This review aims to present an overview of current concepts for both scanner output metrics and for patient dosimetry and will comment on their strengths and weaknesses. Controversial issues such as the appropriateness of the CT dose index (CTDI) are discussed in detail. A review of approaches to patient dose assessment presently in practice, of the dose levels encountered and options for further dose optimization are also given and discussed. Patient dose assessment remains a topic for further improvement and for international consensus. All approaches presently in use are based on Monte Carlo (MC) simulations. Estimates for effective dose are established, but they are crude and not patient-specific; organ dose estimates are rarely available. Patient- and organ-specific dose estimates can be provided with adequate accuracy and independent of CTDI phantom measurements by fast MC simulations. Such information, in particular on 3D dose distributions, is important and helpful in optimization efforts. Dose optimization has been performed very successfully in recent years and even resulted in applications with effective dose values of below 1 mSv. In general, a trend towards lower dose values based on technical innovations has to be acknowledged. Effective dose values are down to clearly below 10 mSv on average, and there are a number of applications such as cardiac and pediatric CT which are performed routinely below 1 mSv on modern equipment. PMID:24434792

  15. Myocardial perfusion with multi-detector computed tomography: quantitative evaluation

    International Nuclear Information System (INIS)

    The objective of this work is to evaluate the skill of multidetector computer tomography, to quantify the different patterns of intensification during the evaluation of the myocardial perfusion. 45 patients were studied with suspicion of cardiovascular disease. Multi-detector computed tomography was utilized on patients at rest and in effort with pharmacological stress, after the administration of dipyridamole. Also they were evaluated using nuclear medicine

  16. 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

    Institute of Scientific and Technical Information of China (English)

    刘伟宾

    2011-01-01

    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

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

    International Nuclear Information System (INIS)

    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 99mTc-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.)

  18. Skeletal dosimetry in cone beam computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Walters, B. R. B.; Ding, G. X.; Kramer, R.; Kawrakow, I. [Ionizing Radiation Standards, National Research Council of Canada, Ottawa K1A OR6 (Canada); Department of Radiation Oncology, Vanderbilt-Ingram Cancer Center, Vanderbilt University School of Medicine, Nashville, Tennessee 37232-5671 (United States); Departamento de Energia Nuclear, Universidade Federal de Pernambuco, Avenida Professor Luiz Freire 1000, Cidade Universitaria, CEP 50740-540, Recife, Pernambuco (Brazil); Ionizing Radiation Standards, National Research Council of Canada, Ottawa K1A OR6 (Canada)

    2009-07-15

    Cone beam computed tomography (CBCT) is a relatively new patient imaging technique that has proved invaluable for treatment target verification and patient positioning during image-guided radiotherapy (IGRT). It has been shown that CBCT results in additional dose to bone that may amount to 10% of the prescribed dose. In this study, voxelized human phantoms, FAX06 (adult female) and MAX06 (adult male), are used together with phase-space data collected from a realistic model of a CBCT imager to calculate dose in the red bone marrow (RBM) and bone surface cells (BSCs), the two organs at risk within the bone spongiosa, during simulated head and neck, chest and pelvis CBCT scans. The FAX06/MAX06 phantoms model spongiosa based on micro-CT images, filling the relevant phantom voxels, which are 0.12x0.12x0.12 cm{sup 3}, with 17x17x17 {mu}m{sup 3} microvoxels to form a micromatrix of trabecular bone and bone marrow. FAX06/MAX06 have already been implemented in an EGSnrc-based Monte Carlo code to simulate radiation transport in the phantoms; however, this study required significant modifications of the code to allow use of phase-space data from a simulated CBCT imager as a source and to allow scoring of total dose, RBM dose and BSC dose on a voxel-by-voxel basis. In simulated CBCT scans, the BSC dose is significantly greater than the dose to other organs at risk. For example, in a simulated head and neck scan, the average BSC dose is 25% higher than the average dose to eye lens ({approx}8.3 cGy), and 80% greater than the average dose to brain (5.7 cGy). Average dose to RBM, on the other hand, is typically only {approx}50% of the average BSC dose and less than the dose to other organs at risk (54% of the dose to eye lens and 76% of dose to brain in a head and neck scan). Thus, elevated dose in bone due to CBCT results in elevated BSC dose. This is potentially of concern when using CBCT in conjunction with radiotherapy treatment.

  19. Skeletal dosimetry in cone beam computed tomography.

    Science.gov (United States)

    Walters, B R B; Ding, G X; Kramer, R; Kawrakow, I

    2009-07-01

    Cone beam computed tomography (CBCT) is a relatively new patient imaging technique that has proved invaluable for treatment target verification and patient positioning during image-guided radiotherapy (IGRT). It has been shown that CBCT results in additional dose to bone that may amount to 10% of the prescribed dose. In this study, voxelized human phantoms, FAX06 (adult female) and MAX06 (adult male), are used together with phase-space data collected from a realistic model of a CBCT imager to calculate dose in the red bone marrow (RBM) and bone surface cells (BSCs), the two organs at risk within the bone spongiosa, during simulated head and neck, chest and pelvis CBCT scans. The FAX06/MAX06 phantoms model spongiosa based on micro-CT images, filling the relevant phantom voxels, which are 0.12 x 0.12 x 0.12 cm3, with 17 x 17 x 17 microm3 microvoxels to form a micromatrix of trabecular bone and bone marrow. FAX06/ MAX06 have already been implemented in an EGSnrc-based Monte Carlo code to simulate radiation transport in the phantoms; however, this study required significant modifications of the code to allow use of phase-space data from a simulated CBCT imager as a source and to allow scoring of total dose, RBM dose and BSC dose on a voxel-by-voxel basis. In simulated CBCT scans, the BSC dose is significantly greater than the dose to other organs at risk. For example, in a simulated head and neck scan, the average BSC dose is 25% higher than the average dose to eye lens (approximately 8.3 cGy), and 80% greater than the average dose to brain (5.7 cGy). Average dose to RBM, on the other hand, is typically only approximately 50% of the average BSC dose and less than the dose to other organs at risk (54% of the dose to eye lens and 76% of dose to brain in a head and neck scan). Thus, elevated dose in bone due to CBCT results in elevated BSC dose. This is potentially of concern when using CBCT in conjunction with radiotherapy treatment. PMID:19673190

  20. Skeletal dosimetry in cone beam computed tomography

    International Nuclear Information System (INIS)

    Cone beam computed tomography (CBCT) is a relatively new patient imaging technique that has proved invaluable for treatment target verification and patient positioning during image-guided radiotherapy (IGRT). It has been shown that CBCT results in additional dose to bone that may amount to 10% of the prescribed dose. In this study, voxelized human phantoms, FAX06 (adult female) and MAX06 (adult male), are used together with phase-space data collected from a realistic model of a CBCT imager to calculate dose in the red bone marrow (RBM) and bone surface cells (BSCs), the two organs at risk within the bone spongiosa, during simulated head and neck, chest and pelvis CBCT scans. The FAX06/MAX06 phantoms model spongiosa based on micro-CT images, filling the relevant phantom voxels, which are 0.12x0.12x0.12 cm3, with 17x17x17 μm3 microvoxels to form a micromatrix of trabecular bone and bone marrow. FAX06/MAX06 have already been implemented in an EGSnrc-based Monte Carlo code to simulate radiation transport in the phantoms; however, this study required significant modifications of the code to allow use of phase-space data from a simulated CBCT imager as a source and to allow scoring of total dose, RBM dose and BSC dose on a voxel-by-voxel basis. In simulated CBCT scans, the BSC dose is significantly greater than the dose to other organs at risk. For example, in a simulated head and neck scan, the average BSC dose is 25% higher than the average dose to eye lens (∼8.3 cGy), and 80% greater than the average dose to brain (5.7 cGy). Average dose to RBM, on the other hand, is typically only ∼50% of the average BSC dose and less than the dose to other organs at risk (54% of the dose to eye lens and 76% of dose to brain in a head and neck scan). Thus, elevated dose in bone due to CBCT results in elevated BSC dose. This is potentially of concern when using CBCT in conjunction with radiotherapy treatment.

  1. Finger fractures imaging: accuracy of cone-beam computed tomography and multislice computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Faccioli, Niccolo; Foti, Giovanni; Barillari, Marco; Mucelli, Roberto Pozzi [University of Verona, Department of Radiology, G.B. Rossi Hospital, Verona (Italy); Atzei, Andrea [University of Verona, Department of Hand Surgery, G.B. Rossi Hospital, Verona (Italy)

    2010-11-15

    To compare the diagnostic accuracy and radiation exposure of cone beam computed tomography (CBCT) and multislice computed tomography (MSCT) in the evaluation of finger fractures. In a 3-year period, 57 consecutive patients with post-traumatic fractures of the metacarpal-phalangeal (MCP), proximal interphalangeal (PIP) and distal interphalangeal (DIP) joints with involvement of the articular surface were studied by means of CBCT and MSCT. Student's t test was used to compare CBCT and MSCT accuracy in evaluating the percentage of joint surface involvement and in detecting bone fragments. The average tissue-absorbed doses of CBCT and MSCT were also compared. A value of p < 0.05 was considered statistically significant. Inter-observer agreement was calculated. In all cases, CBCT allowed the percentage of articular involvement to be correctly depicted compared with MSCT, showing 100% sensitivity and specificity (p < 0.001). A total of 103 bone fragments were depicted on MSCT (mean 3.8 per patient, range 1-23). CBCT indicated 92 out of 103 fragments (89.3%) compared with MSCT (mean diameter of missed fragments 0.9 mm, range 0.6-1.3 mm), with no statistically significant difference between CBCT and MSCT (p < 0.025). Multislice CT radiation exposure was significantly higher than that of CBCT (0.18 mSv vs 0.06 mSv, p < 0.0025). Inter-observer agreement was good (overall {kappa} = 0.89-0.96). Cone beam CT may be considered a valuable imaging tool in the preoperative assessment of finger fractures, when MSCT is not available. (orig.)

  2. Endocrine radionuclide scintigraphy with fusion single photon emission computed tomography/computed tomography

    Science.gov (United States)

    Wong, Ka-Kit; Gandhi, Arpit; Viglianti, Benjamin L; Fig, Lorraine M; Rubello, Domenico; Gross, Milton D

    2016-01-01

    AIM: To review the benefits of single photon emission computed tomography (SPECT)/computed tomography (CT) hybrid imaging for diagnosis of various endocrine disorders. METHODS: We performed MEDLINE and PubMed searches using the terms: “SPECT/CT”; “functional anatomic mapping”; “transmission emission tomography”; “parathyroid adenoma”; “thyroid cancer”; “neuroendocrine tumor”; “adrenal”; “pheochromocytoma”; “paraganglioma”; in order to identify relevant articles published in English during the years 2003 to 2015. Reference lists from the articles were reviewed to identify additional pertinent articles. Retrieved manuscripts (case reports, reviews, meta-analyses and abstracts) concerning the application of SPECT/CT to endocrine imaging were analyzed to provide a descriptive synthesis of the utility of this technology. RESULTS: The emergence of hybrid SPECT/CT camera technology now allows simultaneous acquisition of combined multi-modality imaging, with seamless fusion of three-dimensional volume datasets. The usefulness of combining functional information to depict the bio-distribution of radiotracers that map cellular processes of the endocrine system and tumors of endocrine origin, with anatomy derived from CT, has improved the diagnostic capability of scintigraphy for a range of disorders of endocrine gland function. The literature describes benefits of SPECT/CT for 99mTc-sestamibi parathyroid scintigraphy and 99mTc-pertechnetate thyroid scintigraphy, 123I- or 131I-radioiodine for staging of differentiated thyroid carcinoma, 111In- and 99mTc- labeled somatostatin receptor analogues for detection of neuroendocrine tumors, 131I-norcholesterol (NP-59) scans for assessment of adrenal cortical hyperfunction, and 123I- or 131I-metaiodobenzylguanidine imaging for evaluation of pheochromocytoma and paraganglioma. CONCLUSION: SPECT/CT exploits the synergism between the functional information from radiopharmaceutical imaging and anatomy

  3. Computed tomography in penetrating injury to the eye.

    Science.gov (United States)

    Bhimani, S; Virapongse, C; Sarwar, M; Twist, J F

    1984-05-01

    We used computed tomography to detect and localize foreign bodies in two unusual cases of penetrating injury to the eyes. In one case, a large broken twig appeared to have penetrated the globe and the inferior rectus muscle; in the other, the globe was ruptured by many glass shards . In the first case surgery showed the computed tomographic impression to be incorrect. The globe and the inferior rectus muscle were intact and vision and motility were normal postoperatively. In the second case, swelling made direct visualization impossible, and computed tomography was used to locate the foreign bodies. PMID:6720836

  4. Development of a proton Computed Tomography Detector System

    CERN Document Server

    Naimuddin, Md; Blazey, G; Boi, S; Dyshkant, A; Erdelyi, B; Hedin, D; Johnson, E; Krider, J; Rukalin, V; Uzunyan, S A; Zutshi, V; Fordt, R; Sellberg, G; Rauch, J E; Roman, M; Rubinov, P; Wilson, P

    2015-01-01

    Computer tomography is one of the most promising new methods to image abnormal tissues inside the human body. Tomography is also used to position the patient accurately before radiation therapy. Hadron therapy for treating cancer has become one of the most advantageous and safe options. In order to fully utilize the advantages of hadron therapy, there is a necessity of performing radiography with hadrons as well. In this paper we present the development of a proton computed tomography system. Our second-generation proton tomography system consists of two upstream and two downstream trackers made up of fibers as active material and a range detector consisting of plastic scintillators. We present details of the detector system, readout electronics, and data acquisition system as well as the commissioning of the entire system. We also present preliminary results from the test beam of the range detector.

  5. Development of a proton Computed Tomography detector system

    International Nuclear Information System (INIS)

    Computer tomography is one of the most promising new methods to image abnormal tissues inside the human body. Tomography is also used to position the patient accurately before radiation therapy. Hadron therapy for treating cancer has become one of the most advantegeous and safe options. In order to fully utilize the advantages of hadron therapy, there is a necessity of performing radiography with hadrons as well. In this paper we present the development of a proton computed tomography system. Our second-generation proton tomography system consists of two upstream and two downstream trackers made up of fibers as active material and a range detector consisting of plastic scintillators. We present details of the detector system, readout electronics, and data acquisition system as well as the commissioning of the entire system. We also present preliminary results from the test beam of the range detector

  6. Coronary computed tomography angiography indicates complexity of percutaneous coronary interventions

    OpenAIRE

    Stähli, B E; Bonassin, F; Goetti, R; Küest, S M; Frank, M.; Altwegg, L A; Gebhard, C; Levis, A; Wischnewsky, M. B.; Lüscher, T F; Alkadhi, H.; Kaufmann, P A; Maier, W.

    2012-01-01

    BACKGROUND: Coronary computed tomography angiography (CCTA) provides information regarding lesion morphology and three-dimensional coronary anatomy incremental to coronary angiography. We addressed the question whether preprocedural CCTA bears potential for guiding percutaneous coronary interventions (PCI). METHODS AND RESULTS: Sixty-six coronary lesions attempted with PCI within 6 months of preprocedural CCTA were retrospectively assessed. Lesion parameters from unenhanced computed tomogr...

  7. 3D neutron computed tomography. Requirements and applications

    International Nuclear Information System (INIS)

    Other than X-rays, neutrons can penetrate most metals easily while delivering a high contrast for many light-weight elements. Especially their high sensitivity for hydrogen makes them a valuable tool for the detection of organic materials like lubricants, plastics or sealants within metal housings. Neutron radiography and tomography complement the application of X-ray for the inspection of complex and critical components like in automotive and aerospace applications. An overview about the technical and mathematical differences between neutron and X-ray tomography is given and the imperfections and limitations of a neutron setup are shown. Several examples of technical neutron computed tomography are given. (author)

  8. Dose estimation for paediatric cranial computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Curci Daros, K.A.; Bitelli Medeiros, R. [Sao Paulo Univ. Federal (Brazil); Curci Daros, K.A.; Oliveira Echeimberg, J. de [Centro Univ. Sao Camilo, Sao Paulo (Brazil)

    2006-07-01

    In the last ten years, the number of paediatric computed tomography (CT) scans have increased worldwide, contributing to higher population radiation dose. Technique diversification in paediatrics and different CT equipment technologies have led to various exposure levels complicating precise evaluation of doses and operational conditions necessary for good quality images. The objective of this study was to establish a quantitative relationship between absorbed dose and cranial region in children up to 6 years old undergoing CT exams. Methods: X-ray was measured on the cranial surface of 64 patients undergoing CT using thermoluminescent (T.L.) dosimeters. Forty T.L.D.100 thermoluminescent dosimeters (T.L.D.) were evenly distributed on each patients skin surface along the sagittal axis. Measurements were performed in facial regions exposed to scatter radiation and in the supratentorial and posterior fossa regions, submitted to primary radiation. T.L.D. were calibrated for 120 kV X-ray over the acrylic phantom. T.L. measurements were made with a Harshaw 4000 system. Patient mean T.L. readings were determined for position, pi, of T.L.D. and normalized to the maximum supratentorial reading. From integrating the linear T.L. density function (?) resulting from radiation distribution in each of the three exposed regions, dose fraction was determined in the region of interest, along with total dose under the technical conditions used in that specific exam protocol. For each T.L.D. position along the patient cranium, there were n T.L. measurements with 2% uncertainty due to T.L. reader, and 5% due to thermal treatment of dosimeters. Also, mean T.L. readings and their uncertainties were calculated for each patient at each position, p. Results: Mean linear T.L. density for the region exposed to secondary radiation defined by position, 0.3{<=}p{<=}6 cm, was {rho}((p)=7.9(4)x10{sup -2}+7(5)x10{sup -5}p{sup 4.5(4)} cm{sup -1}; exposed to primary X-ray for the posterior fossa

  9. Evaluating iterative reconstruction performance in computed tomography

    International Nuclear Information System (INIS)

    Purpose: Iterative reconstruction (IR) offers notable advantages in computed tomography (CT). However, its performance characterization is complicated by its potentially nonlinear behavior, impacting performance in terms of specific tasks. This study aimed to evaluate the performance of IR with both task-specific and task-generic strategies. Methods: The performance of IR in CT was mathematically assessed with an observer model that predicted the detection accuracy in terms of the detectability index (d′). d′ was calculated based on the properties of the image noise and resolution, the observer, and the detection task. The characterizations of image noise and resolution were extended to accommodate the nonlinearity of IR. A library of tasks was mathematically modeled at a range of sizes (radius 1–4 mm), contrast levels (10–100 HU), and edge profiles (sharp and soft). Unique d′ values were calculated for each task with respect to five radiation exposure levels (volume CT dose index, CTDIvol: 3.4–64.8 mGy) and four reconstruction algorithms (filtered backprojection reconstruction, FBP; iterative reconstruction in imaging space, IRIS; and sinogram affirmed iterative reconstruction with strengths of 3 and 5, SAFIRE3 and SAFIRE5; all provided by Siemens Healthcare, Forchheim, Germany). The d′ values were translated into the areas under the receiver operating characteristic curve (AUC) to represent human observer performance. For each task and reconstruction algorithm, a threshold dose was derived as the minimum dose required to achieve a threshold AUC of 0.9. A task-specific dose reduction potential of IR was calculated as the difference between the threshold doses for IR and FBP. A task-generic comparison was further made between IR and FBP in terms of the percent of all tasks yielding an AUC higher than the threshold. Results: IR required less dose than FBP to achieve the threshold AUC. In general, SAFIRE5 showed the most significant dose reduction

  10. Evaluating iterative reconstruction performance in computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Baiyu, E-mail: chenby04@gmail.com; Solomon, Justin [Medical Physics Graduate Program, Duke University, Durham, North Carolina 27705 and Carl E. Ravin Advanced Imaging Laboratories, Duke University, Durham, North Carolina 27705 (United States); Ramirez Giraldo, Juan Carlos [Siemens Healthcare, Malvern, Pennsylvania 19355 (United States); Samei, Ehsan [Medical Physics Graduate Program, Duke University, Durham, North Carolina 27705 (United States); Carl E. Ravin Advanced Imaging Laboratories, Duke University, Durham, North Carolina 27705 (United States); Departments of Radiology, Physics, Biomedical Engineering, and Electronic and Computer Engineering, Duke University, Durham, North Carolina 27705 (United States)

    2014-12-15

    Purpose: Iterative reconstruction (IR) offers notable advantages in computed tomography (CT). However, its performance characterization is complicated by its potentially nonlinear behavior, impacting performance in terms of specific tasks. This study aimed to evaluate the performance of IR with both task-specific and task-generic strategies. Methods: The performance of IR in CT was mathematically assessed with an observer model that predicted the detection accuracy in terms of the detectability index (d′). d′ was calculated based on the properties of the image noise and resolution, the observer, and the detection task. The characterizations of image noise and resolution were extended to accommodate the nonlinearity of IR. A library of tasks was mathematically modeled at a range of sizes (radius 1–4 mm), contrast levels (10–100 HU), and edge profiles (sharp and soft). Unique d′ values were calculated for each task with respect to five radiation exposure levels (volume CT dose index, CTDI{sub vol}: 3.4–64.8 mGy) and four reconstruction algorithms (filtered backprojection reconstruction, FBP; iterative reconstruction in imaging space, IRIS; and sinogram affirmed iterative reconstruction with strengths of 3 and 5, SAFIRE3 and SAFIRE5; all provided by Siemens Healthcare, Forchheim, Germany). The d′ values were translated into the areas under the receiver operating characteristic curve (AUC) to represent human observer performance. For each task and reconstruction algorithm, a threshold dose was derived as the minimum dose required to achieve a threshold AUC of 0.9. A task-specific dose reduction potential of IR was calculated as the difference between the threshold doses for IR and FBP. A task-generic comparison was further made between IR and FBP in terms of the percent of all tasks yielding an AUC higher than the threshold. Results: IR required less dose than FBP to achieve the threshold AUC. In general, SAFIRE5 showed the most significant dose reduction

  11. Multifocal sparganosis mimicking lymphoma involvement: Multimodal imaging findings of ultrasonography, CT, MRI, and position emission tomography-computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Heo, So Young; Park, Ji Yeon; Park, Noh Hyuck; Park, Chan Sub; Kim, Tae Jung [Myongji Hospital, Seonam University College of Medicine, Goyang (Korea, Republic of); Yi, Seong Yoon [Dev. of Hematology-Omcology, Dept. of Internal Medicine, Inje University Ilsan Paik Hospital, Goyang (Korea, Republic of); Jun, Hyun Jung [Dev. of Hematology-Omcology, Dept. of Internal Medicine, Seoul Medical Center, Seoul (Korea, Republic of)

    2016-01-15

    Sparganosis is a rare parasitic disease caused by the migrating plerocercoid larva of Spirometra species tapeworms. The most frequent clinical manifestation is a subcutaneous nodule resembling a neoplasm. In this study, we presented multimodal findings of ultrasonography, computed tomography, magnetic resonance imaging, positron emission tomography-computed tomography and follow-up imagings on multifocal sparganosis, mimicking lymphoma involvement in a patient with lymphoma.

  12. Positron emission tomography-computed tomography has a clinical impact for patients with cervical cancer

    DEFF Research Database (Denmark)

    Sandvik, Rikke Mulvad; Jensen, Pernille Tine; Hendel, Helle W;

    2011-01-01

    Many studies have found that positron emission tomography-computed tomography (PET-CT) has a high sensitivity and specificity in the identification of metastasis in cervical cancer. Herlev Hospital, Denmark, has been performing PET-CTs in stage I-IV cervical cancer since 1 May 2006. The present...... study investigates the positive (PPV) and negative predictive value (NPV) of PET-CT in stage I disease and the clinical impact of the scan results in all disease stages....

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2008-07-15

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

  14. The current concepts of computed tomography for acute stroke

    International Nuclear Information System (INIS)

    Stroke is one of a leading cause of death and disability worldwide. The major advances in stroke therapy in particular invasive therapy lead to application of new imaging techniques. The aim of this review is to present state-of-the-art concepts of computed tomography for acute stroke. The goals of a neuroimaging in acute stroke are to establish a diagnosis as early as possible and to evaluate brain perfusion and intracranial vessels' patency. State-of-the-art imaging in the era of multidetector computed tomography (CT) with high spatial and temporal resolution consists of multimodal CT imaging. Non enhanced CT is necessary for depiction of hemorrhage or early ischemic signs. CT angiography evaluates intravascular thrombi or significant stenosis, and CT perfusion demonstrates salvageable tissue at risk. By combining different imaging techniques in multimodal approach we can acquire information necessary for therapeutic planning and could select patients for thrombolysis. The imaging protocol should be tailored to the patient regarding to the time of onset, necessity and availability of CT modalities. (authors) Key words: Stroke. Computed Tomography (CT). Computed Tomography Angiography (CTA). Computed Tomography Perfusion (CTP)

  15. Morphometric evaluation of bony nasolacrimal canal in a caucasian population with primary acquired nasolacrimal duct obstruction: A multidetector computed tomography study

    Energy Technology Data Exchange (ETDEWEB)

    Bulbul, Erdogan; Yazici, Alper; Yanik, Bahar; Yazici, Hasmet; Demirpolat, Gulen [Balikesir University School of Medicine, Balikesir (Turkmenistan)

    2016-04-15

    The bony nasolacrimal duct (BNLD) morphology as a contributory factor in primary acquired nasolacrimal duct obstruction (PANDO) is still controversial. The objectives of this study were to evaluate the morphometric differences of BNLDs in unilateral PANDO patients between PANDO and non-PANDO sides, as compared with the control group using multidetector computed tomography (CT). Bilateral BNLDs in 39 unilateral PANDO patients and 36 control subjects were retrospectively reviewed. CT images with 0.5-mm thickness were obtained with a 64-slice scanner. The length, volume, coronal orientation type, sagittal orientation angle of BNLD, and relative lacrimal sac-BNLD angle were assessed. The entrance, minimum and distal end transverse diameters (TD) of BNLD was investigated. The mean minimum and distal end BNLD TDs measurements were significantly narrower in PANDO patients, both in PANDO and non-PANDO sides, as compared with the control group (p < 0.001 and p = 0.040, respectively); however, there were no significant differences between PANDO and non-PANDO sides within PANDO patients. The length, entrance TD, volume, coronal orientation type, sagittal orientation angle of BNLD, and relative lacrimal sac-BNLD angle were not significantly different between PANDO patients and control subjects, as well as between PANDO and non-PANDO sides within PANDO patients. The narrow mean minimum and distal end BNLD TD in PANDO patients, in both PANDO and non-PANDO sides, may be associated with PANDO development. The lack of difference between PANDO and non-PANDO sides within PANDO patients and some overlap between PANDO patients and control subjects suggest that narrow BNLD is not the sole factor.

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

    Energy Technology Data Exchange (ETDEWEB)

    Sohns, J.M.; Lotz, J. [Goettingen University Medical Center (Germany). Inst. for Diagnostic and Interventional Radiology; German Center for Cardiovascular Research (DZHK), Goettingen (Germany); Menke, J.; Staab, W.; Fasshauer, M.; Kowallick, J.T.; Zwaka, P.A.; Schwarz, A. [Goettingen University Medical Center (Germany). Inst. for Diagnostic and Interventional Radiology; Spiro, J. [Koeln University Hospital (Germany). Radiology; Bergau, L.; Unterberg-Buchwald, C. [Goettingen University Medical Center (Germany). Cardiology and Pneumology

    2014-09-15

    Purpose: The aim of this study was to assess the incidence of cardiac and significant extra-cardiac findings in clinical computed tomography of the heart in patients with atrial fibrillation before pulmonary vein isolation (PVI). Materials and Methods: 224 patients (64 ± 10 years; male 63%) with atrial fibrillation were examined by cardiac 64-slice multidetector CT before PVI. Extra-cardiac findings were classified as 'significant' if they were recommended to additional diagnostics or therapy, and otherwise as 'non-significant'. Additionally, cardiac findings were documented in detail. Results: A total of 724 cardiac findings were identified in 203 patients (91% of patients). Additionally, a total of 619 extra-cardiac findings were identified in 179 patients (80% of patients). Among these extra-cardiac findings 196 (32%) were 'significant', and 423 (68%) were 'non-significant'. In 2 patients (1%) a previously unknown malignancy was detected (esophageal cancer and lung cancer, local stage, no metastasis). 203 additional imaging diagnostics followed to clarify the 'significant' findings (124 additional CT, costs 38,314.69 US dollars). Overall, there were 3.2 cardiac and 2.8 extra-cardiac findings per patient. Extra-cardiac findings appear significantly more frequently in patients over 60 years old, in smokers and in patients with a history of cardiac findings (p < 0.05). Conclusion: Cardiac CT scans before PVI should be screened for extracardiac incidental findings that could have important clinical implications for each patient. (orig.)

  17. Shielding Calculations for Positron Emission Tomography - Computed Tomography Facilities

    Energy Technology Data Exchange (ETDEWEB)

    Baasandorj, Khashbayar [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Yang, Jeongseon [Korea Institute of Nuclear Safety, Daejeon (Korea, Republic of)

    2015-10-15

    Integrated PET-CT has been shown to be more accurate for lesion localization and characterization than PET or CT alone, and the results obtained from PET and CT separately and interpreted side by side or following software based fusion of the PET and CT datasets. At the same time, PET-CT scans can result in high patient and staff doses; therefore, careful site planning and shielding of this imaging modality have become challenging issues in the field. In Mongolia, the introduction of PET-CT facilities is currently being considered in many hospitals. Thus, additional regulatory legislation for nuclear and radiation applications is necessary, for example, in regulating licensee processes and ensuring radiation safety during the operations. This paper aims to determine appropriate PET-CT shielding designs using numerical formulas and computer code. Since presently there are no PET-CT facilities in Mongolia, contact was made with radiological staff at the Nuclear Medicine Center of the National Cancer Center of Mongolia (NCCM) to get information about facilities where the introduction of PET-CT is being considered. Well-designed facilities do not require additional shielding, which should help cut down overall costs related to PET-CT installation. According to the results of this study, building barrier thicknesses of the NCCM building is not sufficient to keep radiation dose within the limits.

  18. Evaluation of myocardial ischemia by multiple detector computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Fernandes, Fabio Vieira, E-mail: rccury@me.com [Hospital do Coracao (HCor), Sao Paulo, SP (Brazil); Cury, Roberto Caldeira [Hospital Samaritano, Sao Paulo, SP (Brazil)

    2015-01-15

    For years, cardiovascular diseases have been the leading cause of death worldwide, bringing on important social and economic consequences. Given this scenario, the search for a method capable of diagnosing coronary artery diseases in an early and accurate way is increasingly higher. The coronary computed tomography angiogram is already widely established for the stratification of coronary artery diseases, and, more recently, the computed tomography myocardial perfusion imaging has been providing relevant information by correlating ischemia and the coronary anatomy. The objective of this review is to describe the evaluation of myocardial ischemia by multiple detector computed tomography. This study will resort to controlled clinical trials that show the possibility of a single method to identify the atherosclerotic load, presence of coronary artery luminal narrowing and possible myocardial ischemia, by means of a fast, practical and reliable method validated by a multicenter study. (author)

  19. Utility of the computed tomography indices on cone beam computed tomography images in the diagnosis of osteoporosis in women

    Energy Technology Data Exchange (ETDEWEB)

    Koh, Kwang Joon; Kim, Kyung A [School of Dentistry, Chonbuk National University, Jeonju (Korea, Republic of)

    2011-09-15

    This study evaluated the potential use of the computed tomography indices (CTI) on cone beam CT (CBCT) images for an assessment of the bone mineral density (BMD) in postmenopausal osteoporotic women. Twenty-one postmenopausal osteoporotic women and 21 postmenopausal healthy women were enrolled as the subjects. The BMD of the lumbar vertebrae and femur were calculated by dual energy X-ray absorptiometry (DXA) using a DXA scanner. The CBCT images were obtained from the unilateral mental foramen region using a PSR-9000N Dental CT system. The axial, sagittal, and coronal images were reconstructed from the block images using OnDemend3D. The new term 'CTI' on CBCT images was proposed. The relationship between the CT measurements and BMDs were assessed and the intra-observer agreement was determined. There were significant differences between the normal and osteoporotic groups in the computed tomography mandibular index superior (CTI(S)), computed tomography mandibular index inferior (CTI(I)), and computed tomography cortical index (CTCI). On the other hand, there was no difference between the groups in the computed tomography mental index (CTMI: inferior cortical width). CTI(S), CTI(I), and CTCI on the CBCT images can be used to assess the osteoporotic women.

  20. Computed tomography of the thorax in children with cystic fibrosis

    International Nuclear Information System (INIS)

    We studied retrospectively the value of computed tomography of the thorax in patients suffering from cystic fibrosis. Twenty-six patients were studied, which showed as the most frequency pulmonary findings bronchial wall thickening in 22 patients (84.6), followed by bronchiectasis in 16 patients (61.5%). Less frequent finding were ill-defined patch consolidation, mucoid impaction, bullaes and atelectasis. We found a predominant distribution of bronchial wall thickening and bronchiectasis in the upper lobes of the lungs. Computed tomography is the more sensitive technique for early visualization and location of the manifestations of cystic fibrosis bronchopathy. (author)

  1. A controlled study of positron-emission-tomography and positron-emission-tomography/computed tomography in differential diagnosis of solitary pulmonary nodules-report of 60 cases

    Institute of Scientific and Technical Information of China (English)

    DING Qi-yong; HUA Yan-qing; ZHANG Guo-zhen; ZHAO Jun; GUAN Yi-hui; GE Xiao-jun; MAO Ding-biao; ZUO Chuan-tao

    2005-01-01

    @@ The differential diagnosis of solitary pulmonary nodules (SPNs) remains a challenge. It is acknowledged that combining positron-emission tomography (PET) and computed tomography (CT) offers the most reliable noninvasive method for the diagnosis of SPNs.

  2. Missing wedge computed tomography by iterative algorithm DIRECTT.

    Science.gov (United States)

    Kupsch, Andreas; Lange, Axel; Hentschel, Manfred P; Lück, Sebastian; Schmidt, Volker; Grothausmann, Roman; Hilger, André; Manke, Ingo

    2015-01-01

    A strategy to mitigate typical reconstruction artefacts in missing wedge computed tomography is presented. These artefacts appear as elongations of reconstructed details along the mean direction (i.e. the symmetry centre of the projections). Although absent in standard computed tomography applications, they are most prominent in advanced electron tomography and also in special topics of X-ray and neutron tomography under restricted geometric boundary conditions. We investigate the performance of the DIRECTT (Direct Iterative Reconstruction of Computed Tomography Trajectories) algorithm to reduce the directional artefacts in standard procedures. In order to be sensitive to the anisotropic nature of missing wedge artefacts, we investigate isotropic substructures of metal foam as well as circular disc models. Comparison is drawn to filtered backprojection and algebraic techniques. Reference is made to reconstructions of complete data sets. For the purpose of assessing the reconstruction quality, Fourier transforms are employed to visualize the missing wedge directly. Deficient reconstructions of disc models are evaluated by a length-weighted kernel density estimation, which yields the probabilities of boundary orientations. The DIRECTT results are assessed at different signal-to-noise ratios by means of local and integral evaluation parameters. PMID:26367127

  3. Diagnostic utility of fluorodeoxyglucose positron emission tomography/computed tomography in pyrexia of unknown origin

    International Nuclear Information System (INIS)

    The present study was undertaken to evaluate the diagnostic utility of fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography (F-18 FDG PET/CT) in patients presenting as pyrexia of unknown origin (PUO). Forty-seven patients (31 males and 16 females; mean age of 42.7 ± 19.96 years) presenting as PUO to the Department of Medicine at the All India Institute of Medical Sciences, New Delhi over a period of 2 years underwent F-18 FDG PET/CT. PET ⁄ CT was considered supportive when its results correlated with the final definitive diagnosis. Final diagnosis was made on the basis of combined evaluation of history, clinical findings, investigations, and response to treatment. Thirty-five PET/CT studies (74.5%) were positive. However, only 18 (38.3%) were supportive of the final diagnosis. In three patients (6.4%), PET/CT was considered diagnostic as none of the other investigations including contrast-enhanced computed tomography of chest and abdomen, and directed tissue sampling could lead to the final diagnosis. All these three patients were diagnosed as aortoarteritis. Fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography is an important emerging modality in the workup of PUO. It supported the final diagnosis in 38% of our patients and was diagnostic in 6.4% of patients. Thus, PET/CT should only be considered as second-line investigation for the diagnostic evaluation of PUO; especially in suspected noninfectious inflammatory disorders

  4. Industrial Computed Tomography using Proximal Algorithm

    KAUST Repository

    Zang, Guangming

    2016-04-14

    In this thesis, we present ProxiSART, a flexible proximal framework for robust 3D cone beam tomographic reconstruction based on the Simultaneous Algebraic Reconstruction Technique (SART). We derive the proximal operator for the SART algorithm and use it for minimizing the data term in a proximal algorithm. We show the flexibility of the framework by plugging in different powerful regularizers, and show its robustness in achieving better reconstruction results in the presence of noise and using fewer projections. We compare our framework to state-of-the-art methods and existing popular software tomography reconstruction packages, on both synthetic and real datasets, and show superior reconstruction quality, especially from noisy data and a small number of projections.

  5. Detection of hepatic tumor by means of single photon emission computed tomography, Gray scale ultrasonography, and computed tomography

    International Nuclear Information System (INIS)

    We have studied the hepatic tumor detection by single photon emission computed tomography (SPECT) using rotatory chair and gamma camera. SPECT were taken by multiple section slice not only in transaxial view, but also in frontal and sagital. The results were superior in detectability to conventional liver scintiphoto (CLS). In cases of obstructive jaundice, ultrasonography (US) and/or computed axial tomography (CAT) should be taken before SPECT, because there are various probabilities of evaluation like as false positive by means of SPECT. Simultaneous interpretation of SPECT, US, and CAT was more helpful than independent interpretation

  6. Computed tomography of cystic pancreatic fibrosis

    International Nuclear Information System (INIS)

    The computer tomographic appearances of atrophic and lipomatous degeneration of the pancreas in cystic pancreatic fibrosis are described. CT exploration of the pancreas in recommended, particularly in differential diagnostic aspects of cystic fibrosis. (orig.)

  7. Cost-effectiveness of PET and PET/Computed Tomography

    DEFF Research Database (Denmark)

    Gerke, Oke; Hermansson, Ronnie; Hess, Søren;

    2015-01-01

    measure by means of incremental cost-effectiveness ratios when considering the replacement of the standard regimen by a new diagnostic procedure. This article discusses economic assessments of PET and PET/computed tomography reported until mid-July 2014. Forty-seven studies on cancer and noncancer...

  8. Micro-computed tomography: an alternative method for shark ageing.

    Science.gov (United States)

    Geraghty, P T; Jones, A S; Stewart, J; Macbeth, W G

    2012-04-01

    Micro-computed tomography (microCT) produced 3D reconstructions of shark Carcharhinus brevipinna vertebrae that could be virtually sectioned along any desired plane, and upon which growth bands were readily visible. When compared to manual sectioning, it proved to be a valid and repeatable means of ageing and offers several distinct advantages over other ageing methods. PMID:22497384

  9. Radiation dosimetry of computed tomography x-ray scanners

    International Nuclear Information System (INIS)

    This report describes the development and application of the methods employed in National Radiation Laboratory (NRL) surveys of computed tomography x-ray scanners (CT scanners). It includes descriptions of the phantoms and equipment used, discussion of the various dose parameters measured, the principles of the various dosimetry systems employed and some indication of the doses to occupationally exposed personnel

  10. Multidetector computed tomography of jaw lesions in children and adolescents

    International Nuclear Information System (INIS)

    Full text: Jaw lesions in paediatric and adolescent population are uncommon and can arise in odontogenic or non-odontogenic tissues. With the advent of multidetector computed tomography (MDCT), algorithm for imaging jaw lesions has changed dramatically. This pictorial essay describes the imaging appearance of commonly encountered jaw lesions in children and adolescents with emphasis on MDCT findings

  11. Paradigm of pretest risk stratification before coronary computed tomography

    DEFF Research Database (Denmark)

    Jensen, Jesper Møller; Øvrehus, Kristian; Nielsen, Lene H;

    2009-01-01

    BACKGROUND: The optimal method of determining the pretest risk of coronary artery disease as a patient selection tool before coronary multidetector computed tomography (MDCT) is unknown. OBJECTIVE: We investigated the ability of 3 different clinical risk scores to predict the outcome of coronary ...

  12. Computed Tomography Features of Spontaneously Perforated Pyometra: A Case Report

    Energy Technology Data Exchange (ETDEWEB)

    Chan, K.S.; Tan, C.K.; Mak, C.W.; Chia, C.C.; Kuo, C.Y.; Yu, W.L. [Chi-Mei Medical Center, Tainan, Taiwan (China). Depts. of Intensive Care Medicine, Radiology, Obstetrics and Gynecology, and Surgery

    2006-03-15

    Spontaneous perforation of pyometra is an extremely rare emergent gynecologic disease. We report a 73-year-old woman with a spontaneously perforated pyometra presenting with acute abdomen in the emergency department. A dedicated computed tomography examination of the abdominal and pelvic regions revealed the diagnosis. The patient recovered well after surgical intervention and antibiotic treatment.

  13. Computed tomography of the human developing anterior skull base

    NARCIS (Netherlands)

    J. van Loosen (J.); A.I.J. Klooswijk (A. I J); D. van Velzen (D.); C.D.A. Verwoerd (Carel)

    1990-01-01

    markdownabstractAbstract The ossification of the anterior skull base, especially the lamina cribrosa, has been studied by computed tomography and histopathology. Sixteen human fetuses, (referred to our laboratory for pathological examination after spontaneous abortion between 18 and 32 weeks of ge

  14. Tracheo-oesophageal fistula diagnosed with multidetector computed tomography.

    LENUS (Irish Health Repository)

    Hodnett, Pa

    2009-04-01

    This case highlights important issues in investigation of patients with suspected tracheo-oesophageal fistula including the value of multidetector computed tomography, the importance of thorough imaging evaluation when high clinical suspicion of tracheo-oesophageal fistula exists and the value of close interaction between radiologists and intensive care physicians in the investigation of these patients.

  15. An Easily Assembled Laboratory Exercise in Computed Tomography

    Science.gov (United States)

    Mylott, Elliot; Klepetka, Ryan; Dunlap, Justin C.; Widenhorn, Ralf

    2011-01-01

    In this paper, we present a laboratory activity in computed tomography (CT) primarily composed of a photogate and a rotary motion sensor that can be assembled quickly and partially automates data collection and analysis. We use an enclosure made with a light filter that is largely opaque in the visible spectrum but mostly transparent to the near…

  16. RADIAL COMPUTED TOMOGRAPHY OF AIR CONTAMINANTS USING OPTICAL REMOTE SENSING

    Science.gov (United States)

    The paper describes the application of an optical remote-sensing (ORS) system to map air contaminants and locate fugitive emissions. Many ORD systems may utilize radial non-overlapping beam geometry and a computed tomography (CT) algorithm to map the concentrations in a plane. In...

  17. Computed Tomography-Enhanced Anatomy Course Using Enterprise Visualization

    Science.gov (United States)

    May, Hila; Cohen, Haim; Medlej, Bahaa; Kornreich, Liora; Peled, Nathan; Hershkovitz, Israel

    2013-01-01

    Rapid changes in medical knowledge are forcing continuous adaptation of the basic science courses in medical schools. This article discusses a three-year experience developing a new Computed Tomography (CT)-based anatomy curriculum at the Sackler School of Medicine, Tel Aviv University, including describing the motivations and reasoning for the…

  18. Computed tomography in the diagnosis of the lumbar disc herniation

    Energy Technology Data Exchange (ETDEWEB)

    Iwakura, Yuichiro (Yatsushiro General Hospital, Kumamoto (Japan)); Hayashi, Yasuo; Suzuki, Mutsuaki; Uemura, Mitsuharu; Fukuda, Kazuyuki; Koito, Hirofumi

    1984-06-01

    In this study, effectiveness of computed tomography (CT) in diagnosing lumbar disc herniation was evaluated. Twenty CT examinations which were interpreted as positive for a herniated disc, and were comfirmed by myelography, were reviewed. In 19 patients, CT demonstrated posterior protrusion of the disc but in one normal disc. Three typical cases were described. This study suggests that CT accurately demonstrates lumbar disc herniation.

  19. The role of computed tomography in modern paediatric uroradiology

    International Nuclear Information System (INIS)

    Computed tomography (CT) has developed a well-recognised role within paediatric uroradiology, especially in imaging of trauma, malignancy (in particular Wilms' tumour), atypical infection, and congenital urogenital abnormalities. CT can also be used for problem solving in nephrolithiasis and renal transplant assessment. These applications are illustrated and discussed, with an emphasis on particular information that can be gained from the CT study

  20. Improvement of reconstructed image quality of neutron computed tomography

    International Nuclear Information System (INIS)

    Neutron computed tomography has been studied. Endeavor has been given to obtain high image quality of CT reconstruction. Film method is comparatively preferred to dynamic neutron TV one. Some models for nuclear fuels have been reconstructed. Dispersion of 300 μm Eu-particles in TiO2 pellets, which simulate PuO2/UO2 nuclear fuel, have been reconstructed

  1. Geometrical metrology on silicone rubber by computed tomography

    DEFF Research Database (Denmark)

    Müller, Pavel; Pacurar, Ramona Alexandra; De Chiffre, Leonardo;

    2011-01-01

    Computed tomography (CT) represents a suitable measuring technique for investigation of deformable materials, since no forces are developed on the part during scanning. As for any other measuring instruments, the traceability of the CT scanners needs to be assured. An investigation on geometrical...

  2. Bone densitometry in healthy cats by quantitative computed tomography

    International Nuclear Information System (INIS)

    The radiodensity of the trabecular bone of the lumbar vertebrae in 16 healthy adult cats was studied using quantitative computed tomography (QCT). The average radiodensity of the trabecular bone of the second lumbar vertebra was 436.1 +- 42.1 Hounsfield units. However, there was a nonhomogeneous radiodensity distribution of the vertebral body. (author)

  3. Coronary computed tomography - present status and future directions

    NARCIS (Netherlands)

    Apfaltrer, P.; Schoepf, U. J.; Vliegenthart, R.; Rowe, G. W.; Spears, J. R.; Fink, C.; Nance, J. W.

    2011-01-01

    The use of coronary computed tomography angiography (cCTA) is growing rapidly, in large part because of fast-paced technical innovations that have increased diagnostic accuracy while providing new opportunities for radiation dose reduction. cCTA using recent generation CT scanners has been repeatedl

  4. COMPUTED TOMOGRAPHY IN HYDATID CYST OF THE ORBIT

    Directory of Open Access Journals (Sweden)

    K. Abbassioun

    1982-07-01

    Full Text Available Two cases of hydatid cysts of the orbit causing unilateral exophthalmos are reported. Diagnosis were suspected by means of computed tomography (CT and confirmed at Operation. CT changes are described and its value in diagnosis of this lesion particularly in the endemic areas is stressed.

  5. Computer tomography in Caisson's disease

    Energy Technology Data Exchange (ETDEWEB)

    Horvath, F.; Csobaly, S.

    1981-07-01

    Computer tomography was performed on 20 patients with the early stages of Caisson osteoarthropathy, as well as in other patients with chronic bone infarcts. From their results the authors have formed the opinion that CT is valuable, not only in the diagnosis of early cases, but that it can provide significant information concerning the osteopathy and bone infarcts.

  6. Tolerance Verification of an Industrial Assembly using Computed Tomography

    DEFF Research Database (Denmark)

    Stolfi, Alessandro; De Chiffre, Leonardo; Regi, Francesco

    2016-01-01

    This paper reports on results of tolerance verification of a multi-material assembly by using Computed Tomography (CT). The workpiece comprises three parts which are made out of different materials. Five different measurands were inspected. The calculation of measurement uncertainties was attempt...

  7. Computed tomography of the gastro-intestinal tract : its value

    International Nuclear Information System (INIS)

    The subject discussed include indications and accuracy of CT - computed tomography, technical considerations, common pitfalls in CT interpretation, parameters for CT evaluation, benign lesions, double halo and target signs, hyperattenuated, inflammatory bowel disease, intestinal ischaemia, primary adenocarcinoma of the GIT, lymphoma and leiomyosarcoma (3 refs.)

  8. Computed Tomography Structural Lung Changes in Discordant Airflow Limitation

    NARCIS (Netherlands)

    F.A.A. Mohamed Hoesein (Firdaus); P.A. de Jong (Pim); J.W.J. Lammers; W.P. Mali (Willem); M. Schmidt (Michael); H.J. de Koning (Harry); C.M. van der Aalst (Carlijn); M. Oudkerk (Matthijs); R. Vliegenthart (Rozemarijn); B.T.J. van Ginneken (Berbke); E.M. van Rikxoort (Eva); P. Zanen (Pieter)

    2013-01-01

    textabstractBackground:There is increasing evidence that structural lung changes may be present before the occurrence of airflow limitation as assessed by spirometry. This study investigated the prevalence of computed tomography (CT) quantified emphysema, airway wall thickening and gas trapping acco

  9. Computed tomography structural lung changes in discordant airflow obstruction

    NARCIS (Netherlands)

    Hoesein, F.A.A.M.; Jong, P.A. de; Lammers, J.W.; Mali, W.P.Th.; Schmidt, M.; Koning, H.J. de; Aalst, C. van der; Oudkerk, M.; Vliegenthart, R.; Ginneken, B. van; Rikxoort, E.M. van; Zanen, P.

    2013-01-01

    Background: There is increasing evidence that structural lung changes may be present before the occurrence of airflow limitation as assessed by spirometry. This study investigated the prevalence of computed tomography (CT) quantified emphysema, airway wall thickening and gas trapping according to cl

  10. Computed Tomography Structural Lung Changes in Discordant Airflow Limitation

    OpenAIRE

    Firdaus A A Mohamed Hoesein; de Jong, Pim A; Lammers, Jan-Willem J; Willem Pthm Mali; Michael Schmidt; de Koning, Harry J.; Carlijn van der Aalst; Matthijs Oudkerk; Rozemarijn Vliegenthart; Bram van Ginneken; van Rikxoort, Eva M; Pieter Zanen

    2013-01-01

    BACKGROUND: There is increasing evidence that structural lung changes may be present before the occurrence of airflow limitation as assessed by spirometry. This study investigated the prevalence of computed tomography (CT) quantified emphysema, airway wall thickening and gas trapping according to classification of airflow limitation (FEV1/FVC 70%; group 2LLN; and group 370% but FEV1

  11. Evaluation by computed tomography in premature and newborn infants

    International Nuclear Information System (INIS)

    By means of cranio-cerebral computed tomography hypoxic brain damage of varying degrees and different types may be demonstrated in premature infants and high-risk newborns. Paraventricular leucomalacia of varying extent up to porencephalic defects are found, as well as cortical infarctions, hemorrhage into brain tissue or ventricles, cerebral atrophy, developing hydrocephalus and congenital anomalies. (orig.)

  12. Position emission tomography with or without computed tomography in the primary staging of Hodgkin's lymphoma

    DEFF Research Database (Denmark)

    Hutchings, Martin; Jakobsen, Annika Loft; Hansen, Mads;

    2006-01-01

    In order to receive the most appropriate therapy, patients with Hodgkin's lymphoma (HL) must be accurately stratified into different prognostic staging groups. Computed tomography (CT) plays a pivotal role in the conventional staging. The aim of the present study was to investigate the value of...

  13. Correction of polychromatic radiogram errors in computer tomography images

    International Nuclear Information System (INIS)

    The polychromatic errors in radiograms obtained by computer tomography are corrected by an image processing facility with e.g. image storage equipment. In the computer tomogram itself no correction of the original projection data is performed. From it there is derived an error image and subtracted from the original image in order to get a corrected image. This is done by assessing the projected data of the biological tissues and calculating therefrom error-projection data by means of mathematical methods. (RW)

  14. Multi-scale analysis of lung computed tomography images

    OpenAIRE

    Gori, I.; Bagagli, F.; Fantacci, M. E.; Martinez, A. Preite; Retico, A.; De Mitri, I.; Donadio, S.; Fulcheri, C.; Gargano, G; Magro, R.; Santoro, M; Stumbo, S

    2009-01-01

    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...

  15. Computed tomography of the temporal horns at Alzheimer's disease

    International Nuclear Information System (INIS)

    In the literature there are different opinions referring to the involvement of the temporal lobes or horns at Alzheimer's disease. Conventionally computed tomogram of the head does not include the temporal horn in its full length. A simple method to demonstrate the temporal horns after cranial computer tomography is described. It allows the evaluation of temporal lobe and temporal horn if questionable alterations at Alzheimer's disease are to be discussed. (orig.)

  16. Global seismic tomography and modern parallel computers

    Directory of Open Access Journals (Sweden)

    A. Piersanti

    2006-06-01

    Full Text Available A fast technological progress is providing seismic tomographers with computers of rapidly increasing speed and RAM, that are not always properly taken advantage of. Large computers with both shared-memory and distributedmemory architectures have made it possible to approach the tomographic inverse problem more accurately. For example, resolution can be quantified from the resolution matrix rather than checkerboard tests; the covariance matrix can be calculated to evaluate the propagation of errors from data to model parameters; the L-curve method can be applied to determine a range of acceptable regularization schemes. We show how these exercises can be implemented efficiently on different hardware architectures.

  17. Single-photon emission computed tomography/computed tomography in abdominal diseases.

    Science.gov (United States)

    Schillaci, Orazio; Filippi, Luca; Danieli, Roberta; Simonetti, Giovanni

    2007-01-01

    Single-photon emission computed tomography (SPECT) studies of the abdominal region are established in conventional nuclear medicine because of their easy and large availability, even in the most peripheral hospitals. It is well known that SPECT imaging demonstrates function, rather than anatomy. It is useful in the diagnosis of various disorders because of its ability to detect changes caused by disease before identifiable anatomic correlates and clinical manifestations exist. However, SPECT data frequently need anatomic landmarks to precisely depict the site of a focus of abnormal tracer uptake and the structures containing normal activity; the fusion with morphological studies can furnish an anatomical map to scintigraphic findings. In the past, software-based fusion of independently performed SPECT and CT or magnetic resonance images have been demonstrated to be time consuming and not useful for routine clinical employment. The recent development of dual-modality integrated imaging systems, which provide SPECT and CT images in the same scanning session, with the acquired images co-registered by means of the hardware, has created a new scenario. The first data have been mainly reported in oncology patients and indicate that SPECT/CT is very useful because it is able to provide further information of clinical value in several cases. In SPECT studies of abdominal diseases, hybrid SPECT/CT can play a role in the differential diagnosis of hepatic hemangiomas located near vascular structures, in precisely detecting and localizing active splenic tissue caused by splenosis in splenectomy patients, in providing important information for therapy optimization in patients submitted to hepatic arterial perfusion scintigraphy, in accurately identifying the involved bowel segments in patients with inflammatory bowel diseases, and in correctly localizing the bleeding sites in patients with gastrointestinal bleeding. PMID:17161039

  18. Cranial computed tomography in infancy and childhood

    International Nuclear Information System (INIS)

    A large number of pediatric cases have been accumulated and categorized according to congenital abnormalities, trauma, hydrocephalus, tumors, and infection. Each category contains background material accompanied by computed-tomographic (CT) illustrations and a related discussion. The material is derived from 6,000 CT scans performed at Children's Hospital National Medical Center in Washington, DC since 1973

  19. Estimation of lung growth using computed tomography

    NARCIS (Netherlands)

    P.A. de Jong (Pim); Y. Nakano (Yasutaka); M.H. Lequin (Maarten); P.J.F.M. Merkus (Peter); H.A.W.M. Tiddens (Harm); J.C. Hogg; H.O. Coxson (Harvey)

    2003-01-01

    textabstractAnatomical studies suggest that normal lungs grow by rapid alveolar addition until about 2 yrs of age followed by a gradual increase in alveolar dimensions. The aim of this study was to examine the hypothesis that normal lung growth can be monitored by computed tomograp

  20. Mycosis fungoides: manifestations on computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Shapeero, L.G.; Young, S.W.

    1983-07-01

    Mtcosis fungoides is a malignant lymphoma of the skin that causes intense erythema, plaques, edema, and induration. The primary computed tomographic findings of mycosis fungoides, i.e., skin thickening, tumorous infiltration, edema of the soft tissues, and lymphadenopathy, are presented in two patients.

  1. Coronary artery visibility in free-breathing young children with congenital heart disease on cardiac 64-slice CT: dual-source ECG-triggered sequential scan vs. single-source non-ECG-synchronized spiral scan

    International Nuclear Information System (INIS)

    The potential impact of dual-source ECG-triggered sequential CT scan on coronary artery visibility has not been evaluated in free-breathing young children. To compare coronary artery visibility in free-breathing young children with congenital heart disease on cardiac 64-slice CT between dual-source ECG-triggered sequential (DSET) scan and single-source non-ECG-synchronized spiral (SSNE) scan. In 93 young children, 108 cardiac 64-slice CT examinations were performed during free-breathing. Visibility of coronary arteries and side branches was compared between SSNE and DSET scans. Heart rates and trigger delays for DSET scan were recorded. Effective dose of each scan technique was calculated. Visual grades were significantly higher (P < 0.001 or =0.011) on DSET scan than on SSNE scan except for the distal left anterior descending artery. Coronary arteries were traceable in 79.3% on DSET scan and 54.3% on SSNE scan in the overlapped scan range (P < 0.0001), and 97.1% and 71.9% for the origins and proximal segments (P < 0.0001). Visibility of side branches was improved on DSET scan by a factor of 2.0. Heart rates and trigger delays for DSET scan were 131 ± 24 beats per min and 199 ± 44 ms, respectively. Effective doses of DSET and SSNE scans were 0.36 ± 0.12 mSv and 0.99 ± 0.23 mSv, respectively. DSET scan improves visibility of coronary arteries on cardiac 64-slice CT in free-breathing young children with congenital heart disease, compared with SSNE scan. (orig.)

  2. Coronary artery visibility in free-breathing young children with congenital heart disease on cardiac 64-slice CT: dual-source ECG-triggered sequential scan vs. single-source non-ECG-synchronized spiral scan

    Energy Technology Data Exchange (ETDEWEB)

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

    2010-10-15

    The potential impact of dual-source ECG-triggered sequential CT scan on coronary artery visibility has not been evaluated in free-breathing young children. To compare coronary artery visibility in free-breathing young children with congenital heart disease on cardiac 64-slice CT between dual-source ECG-triggered sequential (DSET) scan and single-source non-ECG-synchronized spiral (SSNE) scan. In 93 young children, 108 cardiac 64-slice CT examinations were performed during free-breathing. Visibility of coronary arteries and side branches was compared between SSNE and DSET scans. Heart rates and trigger delays for DSET scan were recorded. Effective dose of each scan technique was calculated. Visual grades were significantly higher (P < 0.001 or =0.011) on DSET scan than on SSNE scan except for the distal left anterior descending artery. Coronary arteries were traceable in 79.3% on DSET scan and 54.3% on SSNE scan in the overlapped scan range (P < 0.0001), and 97.1% and 71.9% for the origins and proximal segments (P < 0.0001). Visibility of side branches was improved on DSET scan by a factor of 2.0. Heart rates and trigger delays for DSET scan were 131 {+-} 24 beats per min and 199 {+-} 44 ms, respectively. Effective doses of DSET and SSNE scans were 0.36 {+-} 0.12 mSv and 0.99 {+-} 0.23 mSv, respectively. DSET scan improves visibility of coronary arteries on cardiac 64-slice CT in free-breathing young children with congenital heart disease, compared with SSNE scan. (orig.)

  3. 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

    Institute of Scientific and Technical Information of China (English)

    王聚宝; 奚甘平; 张建福

    2014-01-01

    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。

  4. Computer tomography of large dust clouds in complex plasmas

    International Nuclear Information System (INIS)

    The dust density is a central parameter of a dusty plasma. Here, a tomography setup for the determination of the three-dimensionally resolved density distribution of spatially extended dust clouds is presented. The dust clouds consist of micron-sized particles confined in a radio frequency argon plasma, where they fill almost the entire discharge volume. First, a line-of-sight integrated dust density is obtained from extinction measurements, where the incident light from an LED panel is scattered and absorbed by the dust. Performing these extinction measurements from many different angles allows the reconstruction of the 3D dust density distribution, analogous to a computer tomography in medical applications

  5. Cranial computed tomography in psychiatry. Kraniale Computertomographie in der Psychiatrie

    Energy Technology Data Exchange (ETDEWEB)

    Falkai, P. (Rheinische Landes- und Hochschulklinik Duesseldorf, Psychiatrische Klinik der Heinrich-Heine-Universitaet (Germany)); Bogerts, B. (Rheinische Landes- und Hochschulklinik Duesseldorf, Psychiatrische Klinik der Heinrich-Heine-Universitaet (Germany))

    1993-08-13

    Computed tomography has gained importance as a diagnostic tool in psychiatry to exclude structural brain pathology, but has passed on its role in research to magnetic resonance tomography. It helps to distinguish between senile dementia of Alzheimer type and multi-infarct dementia. The enlargement of the ventricular system and cortical sulci is well established in schizophrenic and affective psychosis. Some alcohol addicts show a considerable degree of cerebral atrophy, only exceeded by demented patients, but this condition is potentially reversible. To screen psychiatric patients by CT is recommendable, as 2-10% of hospitalized psychiatric patients have structural brain disease. (orig.)

  6. Flip-flop phenomenon in systemic sclerosis on fluorodeoxyglucose positron emission tomography/computed tomography

    International Nuclear Information System (INIS)

    Systemic sclerosis (SSc) is a rare autoimmune disease, which may affect multiple organ systems. Fluorine-18-fluorodeoxyglucose (18F-FDG) positron emission tomography/computed tomography (PET/CT) can demonstrate the degree and anatomical extent of involvement in the entire body and coexisting malignancies in connective tissue diseases. We present a case of SSc with an increased 18F-FDG uptake in the cutaneous and subcutaneous tissues even higher than the neighboring skeletal muscles (“flip-flop phenomenon,” that is, an increased 18F-FDG uptake in the skin but a decreased 18F-FDG uptake in the skeletal muscles)

  7. Assessment of asthmatic inflammation using hybrid fluorescence molecular tomography-x-ray computed tomography

    Science.gov (United States)

    Ma, Xiaopeng; Prakash, Jaya; Ruscitti, Francesca; Glasl, Sarah; Stellari, Fabio Franco; Villetti, Gino; Ntziachristos, Vasilis

    2016-01-01

    Nuclear imaging plays a critical role in asthma research but is limited in its readings of biology due to the short-lived signals of radio-isotopes. We employed hybrid fluorescence molecular tomography (FMT) and x-ray computed tomography (XCT) for the assessment of asthmatic inflammation based on resolving cathepsin activity and matrix metalloproteinase activity in dust mite, ragweed, and Aspergillus species-challenged mice. The reconstructed multimodal fluorescence distribution showed good correspondence with ex vivo cryosection images and histological images, confirming FMT-XCT as an interesting alternative for asthma research.

  8. X-ray computed tomography of PEM fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Pfrang, Andreas; Veyret, Damien; Tsotridis, Georgios [Commission of the European Communities, Petten (Netherlands). Joint Reseach Centre, Inst. for Energy; Janssen, Gaby [Energy Research Centre of the Netherlands ECN, Petten (Netherlands). Dept. of Hydrogen and Clean Fossil Fuels

    2010-07-01

    Proton exchange membrane (PEM) fuel cells were investigated by 3D x-ray computed tomography at a voxel size of 0.7 {mu}m. It is shown that this lab-based technique is not only suitable for the investigation of gas diffusion layers (GDL) as well as the investigation of membrane electrode assemblies (MEA), but also allows the calculation of macroscopic physical properties. The resolution of computed tomography is clearly sufficient to image the carbon fiber structure of gas diffusion layers in the as received GDLs as well as GDLs integrated into membrane electrode assemblies. It is also possible to visualize the catalyst layer within the MEA, which allows the investigation of layer thickness and structural defects on a larger scale than with conventional techniques. The macroscopic effective thermal conductivities of the gas diffusion layers were computed based on the 3D GDL structure reconstructed from tomography data to produce more reliable input data for fuel cell modeling. The computation was carried out by solving the energy equation considering a pure thermal conduction problem. The computations show - in agreement with the expectation and experimental data - that the through-plane thermal conductivities are lower than the in-plane thermal conductivities. (orig.)

  9. Comparison of radiation absorbed dose in target organs in maxillofacial imaging with panoramic, conventional linear tomography, cone beam computed tomography and computed tomography

    Directory of Open Access Journals (Sweden)

    Panjnoush M.

    2009-12-01

    Full Text Available "nBackground and Aim: The objective of this study was to measure and compare the tissue absorbed dose in thyroid gland, salivary glands, eye and skin in maxillofacial imaging with panoramic, conventional linear tomography, cone beam computed tomography (CBCT and computed tomography (CT."nMaterials and Methods: Thermoluminescent dosimeters (TLD were implanted in 14 sites of RANDO phantom to measure average tissue absorbed dose in thyroid gland, parotid glands, submandibular glands, sublingual gland, lenses and buccal skin. The Promax (PLANMECA, Helsinki, Finland unit was selected for Panoramic, conventional linear tomography and cone beam computed tomography examinations and spiral Hispeed/Fxi (General Electric,USA was selected for CT examination. The average tissue absorbed doses were used for the calculation of the equivalent and effective doses in each organ."nResults: The average absorbed dose for Panoramic ranged from 0.038 mGY (Buccal skin to 0.308 mGY (submandibular gland, linear tomography ranged from 0.048 mGY (Lens to 0.510 mGY (submandibular gland,CBCT ranged from 0.322 mGY (thyroid glad to 1.144 mGY (Parotid gland and in CT ranged from 2.495 mGY (sublingual gland to 3.424 mGY (submandibular gland. Total effective dose in CBCT is 5 times greater than Panoramic and 4 times greater than linear tomography, and in CT, 30 and 22 times greater than Panoramic and linear tomography, respectively. Total effective dose in CT is 6 times greater than CBCT."nConclusion: For obtaining 3-dimensional (3D information in maxillofacial region, CBCT delivers the lower dose than CT, and should be preferred over a medical CT imaging. Furthermore, during maxillofacial imaging, salivary glands receive the highest dose of radiation.

  10. Comparison of computed tomography and conventional tomography of tumors located in the nasopharynx and paranasal sinuses

    International Nuclear Information System (INIS)

    The value of conventional tomography for the clinical evaluation of tumors located in the nasopharynx and paranasal sinuses has been well established. The present study analyzed the potential improvement of the preoperative evaluation of the extent of those tumors by computed tomography. Conventional tomography was performed with polycycloidal movement. An initial comparison was made using a normal skull phantom. This facilitated the comparison of both diagnostic methods for the recognition of osseous structures. The evaluation of the clinical efficiency of both diagnostic modalities was performed with various cases of early and late tumors involving bony and soft tissue structures of the skull. The correlation of the information obtained by the radiographic methods with the extent of the tumor seen at the operation were the final criteria. Follow-up examinations after radiotherapy wereemployed in several cases. The results and implications of this study are presented. (orig.) 891 MG/orig. 892 MB

  11. Coordinate Metrology by Traceable Computed Tomography

    OpenAIRE

    Müller, Pavel; De Chiffre, Leonardo; Hansen, Hans Nørgaard; Cantatore, Angela

    2013-01-01

    Røntgen computer tomografi (CT) er en måleteknik som er blevet en vigtig teknologi i produktionsmiljøer gennem de seneste år. På grund af et antal fordele ved CT, eksempelvis sammenlignet med koordinatmålemaskiner (CMM’er), er CT på det seneste blevet udbredt indenfor produktions- og koordinatmåleteknik og er aktuelt ved at blive en mere og mere vigtig måleteknik til dimensionsmålinger. Dette er primært på grund af at man med CT relativt hurtigt kan visualisere en komplet tredimensionel model...

  12. Computed tomography in congenital ocular motor apraxia

    Energy Technology Data Exchange (ETDEWEB)

    Eda, I.; Takashima, S.; Kitahara, T.; Ohno, K.; Takeshita, K.

    1984-09-01

    Unusual computed tomographic findings were observed in four patients with congenital ocular motor apraxia (COMA). These (CT) findings were characteristic in the posterior cranial fossa, with a dilated or deformed shape and size of the fourth ventricle, particularly its upper portion. One case revealed partial agenesis of the cerebellar vermis. It was suggested that the four patients subjected to CT showed abnormal topography of the cerebellar vermis or the brain stem. We postulate that these CT findings in COMA may have an important role in its pathogenesis.

  13. Computed tomography of the elbow joint

    Energy Technology Data Exchange (ETDEWEB)

    Burmester, E.; Gmelin, E.; Mendoza, A.S.

    1985-12-01

    An essential pre-condition for the interpretation of computer tomographs of the elbow joint is a knowledge of the normal anatomy. The complexity of the joint requires a definite protocol for the examination, since only in this way it is possible to distinguish all anatomical structures and pathological processes. A clinical example is used to show that CT of the elbow joint is superior to all other radiographic methods for demonstrating osteochondritis dissecans. It is therefore an important additional method for demonstrating the elbow joint.

  14. Intramammary incidental findings on staging computer tomography

    Energy Technology Data Exchange (ETDEWEB)

    Surov, Alexey, E-mail: alex.surow@medizin.uni-halle.de [Department of Radiology, Martin-Luther-University Halle-Wittenberg, Ernst-Grubestr. 40, 06097 Halle (Germany); Fiedler, Eckhard [Department of Dermatology, Martin-Luther-University Halle-Wittenberg, Ernst-Grubestr. 40, 06097 Halle (Germany); Wienke, Andreas [Department of Medical Statistics, Martin-Luther-University Halle-Wittenberg, Ernst-Grubestr. 40, 06097 Halle (Germany); Holzhausen, Hans-Jürgen [Department of Pathology, Martin-Luther-University Halle-Wittenberg, Ernst-Grubestr. 40, 06097 Halle (Germany); Spielmann, Rolf-Peter; Behrmann, Curd [Department of Radiology, Martin-Luther-University Halle-Wittenberg, Ernst-Grubestr. 40, 06097 Halle (Germany)

    2012-09-15

    Purpose: Incidental findings are a common feature in computer tomographic examinations of the chest. Breast incidentalomas, however, were described only sporadically. The purpose of this study was to evaluate retrospectively incidental breast findings and to compare radiological features of benign and malignant breast lesions. Materials and methods: From January 2006 to December 2010 a total of 8105 computer tomographic examinations were performed at our institution. In 89 patients incidental breast lesions were diagnosed. 64 of the identified patients were referred for further clinical, radiological, and hystopathological examination. All patients were female with a median age of 62 years, range 39–82 years. Results: A total of 98 breast lesions were identified in the 64 patients. The mean size was 12.0 ± 8.0 mm. Primary breast carcinoma was identified in 9, breast metastases in 27, and benign findings in 28 patients. Malignant lesions demonstrated more often marked enhancement and showed a higher density compared with benign lesions. Benign findings were more often lobular in shape and had spiculated margins. Most of the breast metastases were round or oval in shape with circumscribed margins and marked homogenous enhancement. There was no significant difference between the breast cancer and benign findings groups in the characteristics of the lesions. Conclusion: The breast is a very important region and should be carefully evaluate on chest CT. There are no certain radiological criteria to differentiate between malignant and benign breast lesions on CT. Therefore all breast incidentalomas should be evaluated by further radiological/histological investigations.

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

    Institute of Scientific and Technical Information of China (English)

    马国林

    2013-01-01

    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

  16. 21 CFR 892.1750 - Computed tomography x-ray system.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Computed tomography x-ray system. 892.1750 Section... (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Diagnostic Devices § 892.1750 Computed tomography x-ray system. (a) Identification. A computed tomography x-ray system is a diagnostic x-ray system intended...

  17. Intracranial calcification on paediatric computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Kendall, B.; Cavanagh, N.

    1986-07-01

    An analysis of the computed tomograms of 18000 children examined consecutively form the basis of an assessment of the diagnostic significance of intracranial calcification. The low incidence of physiological calcification in the pineal and choroid of about 2% up to the age of 8 years, but increasing 5-fold by the age of 15 years, is confirmed. Pathological calcification occurred in 1.6%, the commonest causes being neoplasms (43%), neuroectodermal syndromes (20%) and infections (12%). Diffuse basal ganglia calcification (15%) bore little relation to the diverse clinical symptomatology, and routine biochemical studies showed a disorder of metabolism to be present in only 6 cases. Calcification has not been previously noted in acute haemorrhagic leukoencephalitis, Pertussis or Cocksackie encephalitis, infantile neuraxonal dystrophy, Marinesco-Sjoegren syndrome or in the basal ganglia in neurofibromatosis.

  18. Computed tomography in staging of oesophageal carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Salonen, O.; Kivisaari, L.; Standertskjoeld-Nordenstam, C.G.; Somer, K.; Virkkunen, P.

    1987-01-01

    The computed tomographic (CT) findings in 45 patients with histologically proved oesophageal carcinoma are reviewed. In 20 of these patients the CT findings were correlated with findings at surgery (19 patients) or autopsy (1 patient). Correlation analysis showed that the accuracy of CT in assessing both invasion of adjacent organs and mediastinal and abdominal lymph node involvement is limited. 25 patients were considered inoperable. In 15 of these conclusion was based on CT findings of distant metastases (14 patients) or definite local invasion (1 patient). 10 patients were inoperable for other reasons (general health condition). The value of CT was found to be in detecting distant metastases, thus avoiding unnecessary radical surgery. It is not a reliable way of defining the primary tumour.

  19. Significance of triplane computed tomography in otolaryngology

    International Nuclear Information System (INIS)

    The authors obtained direct sagittal CT scans of the head using a new method for positioning the head of patient in sitting position. Direct sagittal scans are more useful than computed rearranged scans in a better spatial and density resolution. The triplane CT (axial, coronal, and sagittal CT) greatly improves three dimentional recognition of the intracranial and facial structures and the extent of the lesion. A series of patients with various nasal and oropharyngeal tumors was examined with the triplane CT. The advantages of direct sagittal scans are (1) the recognition of localization and extension of the lesion. (2) the evaluation of the extent of the deep facial and nasopharygeal tumors, especially in the intracranial and intraorbital regions. (3) the more accurate determination of staging of the maxillary cancer. (author)

  20. Initial water quantification results using neutron computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Heller, A.K. [Department of Mechanical and Nuclear Engineering, Pennsylvania State University (United States)], E-mail: axh174@psu.edu; Shi, L.; Brenizer, J.S.; Mench, M.M. [Department of Mechanical and Nuclear Engineering, Pennsylvania State University (United States)

    2009-06-21

    Neutron computed tomography is an important imaging tool in the field of non-destructive testing and in fundamental research for many engineering applications. Contrary to X-rays, neutrons can be attenuated by some light materials, such as hydrogen, but can penetrate many heavy materials. Thus, neutron computed tomography is useful in obtaining important three-dimensional information about a sample's interior structure and material properties that other traditional methods cannot provide. The neutron computed tomography system at Pennsylvania State University's Radiation Science and Engineering Center is being utilized to develop a water quantification technique for investigation of water distribution in fuel cells under normal conditions. A hollow aluminum cylinder test sample filled with a known volume of water was constructed for purposes of testing the quantification technique. Transmission images of the test sample at different angles were easily acquired through the synthesis of a dedicated image acquisition computer driving a rotary table controller and an in-house developed synchronization software package. After data acquisition, Octopus (version 8.2) and VGStudio Max (version 1.2) were used to perform cross-sectional and three-dimensional reconstructions of the sample, respectively. The initial reconstructions and water quantification results are presented.

  1. Initial water quantification results using neutron computed tomography

    International Nuclear Information System (INIS)

    Neutron computed tomography is an important imaging tool in the field of non-destructive testing and in fundamental research for many engineering applications. Contrary to X-rays, neutrons can be attenuated by some light materials, such as hydrogen, but can penetrate many heavy materials. Thus, neutron computed tomography is useful in obtaining important three-dimensional information about a sample's interior structure and material properties that other traditional methods cannot provide. The neutron computed tomography system at Pennsylvania State University's Radiation Science and Engineering Center is being utilized to develop a water quantification technique for investigation of water distribution in fuel cells under normal conditions. A hollow aluminum cylinder test sample filled with a known volume of water was constructed for purposes of testing the quantification technique. Transmission images of the test sample at different angles were easily acquired through the synthesis of a dedicated image acquisition computer driving a rotary table controller and an in-house developed synchronization software package. After data acquisition, Octopus (version 8.2) and VGStudio Max (version 1.2) were used to perform cross-sectional and three-dimensional reconstructions of the sample, respectively. The initial reconstructions and water quantification results are presented.

  2. Role of computed tomography in pancreatic trauma

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Sun Hee; Kim, Ki Whang; Lee, Jong Tae; Oh, Sei Jung [College of Medicine, Yonsei University, Seoul (Korea, Republic of)

    1991-03-15

    At Yonsei University Hospital from January 1984 to August 1990, computed tomographic (CT) scans of 13 patients with surgically proven pancreatic injuries after blunt abdominal trauma, including 6 pancreatic lacerations or contusions, 6 pancreatic fractures, and one post-traumatic pseudocyst, were retrospectively reviewed to determine the role and accuracy of the CT in evaluating pancreatic injury. CT can document gross pancreatic injury by showing focal or diffuse enlargement (1), area of diminished attenuation (3), separation (5), focal hematoma (2), and peripancreatic change, including peripancreatic hematoma (2), fluid collection (11), perirenal fascial thickening (10), omental and mesenteric change (5), and bowel change (2). CT correctly diagnosed pancreatic fracture in 5 cases, post-raumatic pseudocyst in 1 case, and pancreatic laceration in 3 cases in 9 of these patients. There were 4 false negative diagnoses, including 3 pancreatic lacerations and 1 pancreatic fracture. A CT is of pancreatic trauma could be difficult to diagnosis in patients who are scanned within 24 hrs after an injury or to distinguish a motion or streak artifact caused by a nasogastric tube or air-oral contrast fluid level in the stomach.

  3. Didactics and training in cardiovascular computed tomography angiography.

    Science.gov (United States)

    Bhojraj, Sanjay D; Al-Mallah, Mouaz H

    2009-01-01

    As the role of cardiovascular computed tomography angiography (CCTA) is further expanded through research, the use of this technology will expand as a result of demand both from medical professionals and the public. To ensure a standardized quality of interpretation of these scans in the face of an increased demand for physicians qualified to interpret these studies, the Society of Cardiovascular Computed Tomography, along with several other professional societies, has proposed a didactic curriculum for the study of CCTA. This review highlights the currently proposed didactic curriculum for the study of CCTA, examines current trends in training for both medical trainees and physicians in practice, and proposes future directions for the study of CCTA. PMID:19203747

  4. Computed tomography of coronary artery anomaly - case report

    International Nuclear Information System (INIS)

    Background: Anomalies of coronary vessels can be described as varies group of congenital heart disease, which can have different level of clinical manifestation and changeable pathophysiological mechanisms. Diagnosis and imaging of vessel course is essential before percutaneous angioplasty intervention and coronary artery bypass grafting as well as before implantation of artificial valve. Case Report: Patient with cardiologic history, previously percutaneous intervention were performed and left circumflex coronary artery were assessed as occluded. Computed tomography revealed anomalous origin of patent circumflex branch arising from right Valsava sinus. Conclusions: Selective percutaneus coronary angiography is challenging in case of coronary anomalies, there are only few indirect symptoms of anomalies. The advantage of computed tomography over classic coronarography is visibility of all patent coronary vessels after single administration of contrast medium. It is possible to describe its anatomic relations, evaluation of walls and its changes

  5. High Resolution Muon Computed Tomography at Neutrino Beam Facilities

    CERN Document Server

    Suerfu, Burkhant

    2015-01-01

    X-ray computed tomography (CT) has an indispensable role in constructing 3D images of objects made from light materials. However, limited by absorption coefficients, X-rays cannot deeply penetrate materials such as copper and lead. Here we show via simulation that muon beams can provide high resolution tomographic images of dense objects and of structures within the interior of dense objects. The effects of resolution broadening from multiple scattering diminish with increasing muon momentum. As the momentum of the muon increases, the contrast of the image goes down and therefore requires higher resolution in the muon spectrometer to resolve the image. The variance of the measured muon momentum reaches a minimum and then increases with increasing muon momentum. The impact of the increase in variance is to require a higher integrated muon flux to reduce fluctuations. The flux requirements and level of contrast needed for high resolution muon computed tomography are well matched to the muons produced in the pio...

  6. Computed tomography of the adrenals in patients with tuberculosis

    International Nuclear Information System (INIS)

    We evaluated the adrenals of individuals without tuberculosis (group 1 - G1) and with tuberculosis (group 2 - G2) using computed tomography. The antero-posterior length, the thickness, and the longitudinal length of the adrenals were compared in G1 and G2. The duration of the disease, the occurrence of morphologic abnormalities in G2, the distribution according to sex, age and skin color were also studied. There was difference in the antero-posterior length and thickness of right adrenal between G1 and G2. A higher prevalence of white skin male individuals was observed in G2. There was no association between duration of the disease and the occurrence of morphologic abnormalities in G2. A higher occurrence of adrenal enlargement was observed in G2. The main computed tomography findings in patients with tuberculosis were enlargement of the adrenal without calcification, enlargement of the adrenal with punctiform calcifications, and residual calcification of the adrenal. (author)

  7. Didactics and training in cardiovascular computed tomography angiography.

    Science.gov (United States)

    Bhojraj, Sanjay D; Al-Mallah, Mouaz H

    2009-01-01

    As the role of cardiovascular computed tomography angiography (CCTA) is further expanded through research, the use of this technology will expand as a result of demand both from medical professionals and the public. To ensure a standardized quality of interpretation of these scans in the face of an increased demand for physicians qualified to interpret these studies, the Society of Cardiovascular Computed Tomography, along with several other professional societies, has proposed a didactic curriculum for the study of CCTA. This review highlights the currently proposed didactic curriculum for the study of CCTA, examines current trends in training for both medical trainees and physicians in practice, and proposes future directions for the study of CCTA.

  8. Computer tomography investigation of epilepsy the brain atrophy

    International Nuclear Information System (INIS)

    The problem of brain atrophy in patients with epilepsy is often discussed in literature. The aim of the study is to present the results of computer tomography measurements of ventricular size and sulci of brain of 90 patients with various electro-clinical forms of epilepsy, including males and females at the age of 15 to 70 years. Computer tomography measurements were performed having in mind 6 parameters (frontal horn index, FHI; Huckman's number, HZ; cella media index,CMI; width of the third and the fourth ventricles; sulci). The results were compared to the CT measurements of a control group of 40 healthy males and females in the same age range.The obtained data indicate high percentage of subcortical atrophy among patients with epilepsy. Ventricular dilatation was found to be in light extent occurring most early in the frontal brain regions (frontal horns and lateral ventricles)., furthermore observed in the young age. (author)

  9. Analytic reconstruction approach for parallel translational computed tomography.

    Science.gov (United States)

    Kong, Huihua; Yu, Hengyong

    2015-01-01

    To develop low-cost and low-dose computed tomography (CT) scanners for developing countries, recently a parallel translational computed tomography (PTCT) is proposed, and the source and detector are translated oppositely with respect to the imaging object without a slip-ring. In this paper, we develop an analytic filtered-backprojection (FBP)-type reconstruction algorithm for two dimensional (2D) fan-beam PTCT and extend it to three dimensional (3D) cone-beam geometry in a Feldkamp-type framework. Particularly, a weighting function is constructed to deal with data redundancy for multiple translations PTCT to eliminate image artifacts. Extensive numerical simulations are performed to validate and evaluate the proposed analytic reconstruction algorithms, and the results confirm their correctness and merits. PMID:25882732

  10. Technical competence in cardiovascular magnetic resonance and computed tomography

    International Nuclear Information System (INIS)

    Cardiovascular magnetic resonance and computed tomography have evolved as very practical and useful techniques applied in clinical cardiology. Due to their rapid acceptance in the cardiology community and widespread use, training of both cardiologists and radiologists on this subspecialty has not been homogeneous so far. This in part explains significant differences observed in the diverse background found in today’s practicing physicians who execute these exams. In order to guide training facilities as well as both payers, contractors and general cardiologists ordering the exam, this document provides a minimum standard that should be accomplished by all physicians who pursue education in the field and for those who already practice in it. The clinical competences listed in this statement are by no means thorough but should be required by all those involved in cardiovascular magnetic resonance and computed tomography as the customary requirements for current and future practitioners. (author)

  11. Acute appendicitis: computed tomography findings - an iconographic essay

    International Nuclear Information System (INIS)

    Acute appendicitis is the most important cause of abdominal pain requiring surgical intervention in the Western world. The early diagnosis of this disease is of paramount relevance for minimizing its morbidity. Imaging methods have represented a huge progress in the diagnosis of this entity, which used to be based essentially on clinical history, physical examination and laboratory tests results, considering that 20% to 33% of patients present with atypical symptoms. Diagnostic difficulty is higher in children, the elderly, and women in childbearing age. The main imaging methods for evaluation of acute appendicitis are ultrasound and computed tomography. The present study is aimed at describing the disease physiopathology, commenting main computed tomography technical aspects, demonstrating and illustrating tomographic findings, and describing main differential diagnoses. (author)

  12. 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

    Directory of Open Access Journals (Sweden)

    Elif Ergun

    2011-03-01

    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.

  13. Intracranial Carotid Calcification on Cranial Computed Tomography

    Science.gov (United States)

    Subedi, Deepak; Zishan, Umme Sara; Chappell, Francesca; Gregoriades, Maria-Lena; Sudlow, Cathie; Sellar, Robin

    2015-01-01

    Background and Purpose— Intracranial internal carotid artery calcification is associated with cerebrovascular risk factors and stroke, but few quantification methods are available. We tested the reliability of visual scoring, semiautomated Agatston score, and calcium volume measurement in patients with recent stroke. Methods— We used scans from a prospective hospital stroke registry and included patients with anterior circulation ischemic stroke or transient ischemic stroke whose noncontrast cranial computed tomographic scans were available electronically. Two raters measured semiautomatic quantitative Agatston score, and calcium volume, and performed qualitative visual scoring using the original 4-point Woodcock score and a modified Woodcock score, where each image on which the internal carotid arteries appeared was scored and the slice scores summed. Results— Intra- and interobserver coefficient of variations were 8.8% and 16.5% for Agatston, 8.8% and 15.5% for calcium volume, and 5.7% and 5.4% for the modified Woodcock visual score, respectively. The modified Woodcock visual score correlated strongly with both Agatston and calcium volume quantitative measures (both R2=0.84; P<0.0001); calcium volume increased by 0.47-mm/point increase in modified Woodcock visual score. Intracranial internal carotid artery calcification increased with age by all measures (eg, visual score, Spearman ρ=0.4; P=0.005). Conclusions— Visual scores correlate highly with quantitative intracranial internal carotid artery calcification measures, with excellent observer agreements. Visual intracranial internal carotid artery scores could be a rapid and practical method for epidemiological studies. PMID:26251250

  14. Indications and Overuse of Computed Tomography in Minor Head Trauma

    OpenAIRE

    Zargar Balaye Jame, Sanaz; MAJDZADEH, Reza; AKBARI SARI, Ali; Rashidian, Arash; ARAB, Mohammad; Rahmani, Hojjat

    2014-01-01

    Background: Computed Tomography (CT) is a useful diagnostic technology, particularly in accident and emergency departments. Objectives: To identify a comprehensive list of indications for application of CT in patients with minor head trauma (MHT) and to determine appropriateness of its use on the basis of this list. Materials and Methods: A cross-sectional study was conducted in three Imaging centers in Tehran. A panel of experts developed a list of CT indications for MHT by reviewing documen...

  15. Computed tomography and the dilated pancreatic duct: An ominous sign

    Energy Technology Data Exchange (ETDEWEB)

    Palmer Gold, R.; Seaman, W.B.

    1981-01-15

    The main pancreatic duct has been visualized with both ultrasound and computed tomography. A normal pancreatic duct has been reported using CT, and controversy persists over whether a normal duct can be routinely imaged with ultrasound. The dilated pancreatic duct has always been associated with disease - usually pancreatitis or a proximal obstructing pancreatic carcinoma. In the patient with no clinical history or laboratory data suggesting pancreatitis, a dilated pancreatic duct implies a proximal tumor.

  16. Soil Macropore Structure Characterized by X-Ray Computed Tomography

    Institute of Scientific and Technical Information of China (English)

    FENG Jie; ZHANG Jia-Bao; ZHU An-Ning; BI Jing-Wei

    2003-01-01

    Undisturbed soil core with many macropores and disturbed soil core with only one macropore (diameter is 10 mm) were probed by x-ray computed tomography (CT). The size, number, shape and continuity of macropores in the transverse and vertical sections of soil were characterized using CT scanning images. The probability densities of macropores in the transverse section of soil core exhibited a logarithmic Γ distribution.Results indicated that CT scanning was a promising nondestructive method for characterizing macropores in soils.

  17. Internal mammary lymph node biopsy guided by computed tomography

    OpenAIRE

    Irving, Henry C; Hardy, Graham J.

    1982-01-01

    Internal mammary lymph node enlargement may be demonstrated using computed tomography (CT), and a confirmatory tissue diagnosis of metastatic involvement may be obtained using fine needle aspiration biopsy with needle tip placement guided by the CT scanner. A case history is described to illustrate how a patient presented 9 years after mastectomy with an internal mammary lymph node metastasis and how cytopathological diagnosis of this metastasis was achieved by CT guided biopsy.

  18. Experimentally determined spectral optimization for dedicated breast computed tomography

    OpenAIRE

    Prionas, Nicolas D.; Huang, Shih-Ying; Boone, John M.

    2011-01-01

    Purpose: The current study aimed to experimentally identify the optimal technique factors (x-ray tube potential and added filtration material∕thickness) to maximize soft-tissue contrast, microcalcification contrast, and iodine contrast enhancement using cadaveric breast specimens imaged with dedicated breast computed tomography (bCT). Secondarily, the study aimed to evaluate the accuracy of phantom materials as tissue surrogates and to characterize the change in accuracy with varying bCT tech...

  19. The possibilities of computer tomography in paecilomycosis of lungs

    OpenAIRE

    Abdusalom Ashurov; Rohila Jabbarova

    2010-01-01

    We have analyzed computed tomography (CT) results of chest in 56 patients with lung injures caused by paecilomycosis fungus at the age from 17 to 59 years. In our investigations, the perverted lung pattern due to pathology of interstitial tissue was observed in 52 (93%) patients of 56 (with chronic bronchitis - 100%, exogenous-allergic alveolitis - 93%, recurrent pneumonia - 100% and with bronchial asthma - 80%). Analysis showed that CT provides wide opportunities in visualization of all spec...

  20. Computed tomography in complex fractures of the ankle joint

    International Nuclear Information System (INIS)

    Diagnostic value of conventional roentgen technique and computed tomography is proofed by examination of 50 patients with sprain fractures of the ankle joint. The dimension of destruction of the distal tibial joint surface is better documented by CT than by other radiological techniques. Additional informations like multifragmentation of the distal tibia or evaluation of reposition impedigment are found more frequently by CT. Therefore indication and planning of the traumatherapy can be assessed better by the traumatologist. (orig.)

  1. The bipartite tarsal navicular bone: radiographic and computed tomography findings

    International Nuclear Information System (INIS)

    Two cases of bipartite tarsal navicular bone are presented. The radiographic and computed tomography (CT) findings of this anatomical variant are described. Correct recognition of this entity is important, both because it may be the cause of symptoms per se, and because it may be misdiagnosed as a fracture. When plain films are not diagnostic, CT scanning is helpful in distinguishing between a fracture and this variant. 6 refs., 4 figs

  2. Pulmonary Thromboembolic Disease: A New Role for Computed Tomography

    OpenAIRE

    Olsan, Adam D.; Matthews, Charles C.; Sullivan, Michael A.

    2002-01-01

    Over the past few years, computed tomography (CT) has emerged as a common noninvasive, definitive, alternative to ventilation-perfusion scintigraphy scan and pulmonary angiography in the evaluation of patients suspected of having pulmonary emboli. Additionally, recent articles have investigated the possibility of using CT to identify deep venous thrombi following a spiral CT pulmonary angiogram. Using the same bolus of contrast as that administered for a CT pulmonary angiogram, the ultimate g...

  3. Ureterolithiasis: classical and atypical findings on unenhanced helical computed tomography.

    Science.gov (United States)

    Vaswani, Kuldeep K; El-Dieb, Adam; Vitellas, Kenneth M; Bennett, William F; Bova, James G

    2002-03-01

    Evaluation of patients with acute flank pain using helical computed tomography (CT) is a well-accepted, rapid, and safe procedure in the emergency setting. Various primary and secondary signs are described in the literature for evaluation of these patients. Our purpose is to demonstrate both the classical findings associated with ureteral calculi on unenhanced helical CT and atypical findings and potential pitfalls. We also provide readers with a systematic approach to interpreting unenhanced helical CT scans performed for acute flank pain.

  4. The role of computed tomography in modern paediatric uroradiology

    Energy Technology Data Exchange (ETDEWEB)

    Maudgil, D.D.; McHugh, K. E-mail: kmchugh@gosh.nhs.uk

    2002-08-01

    Computed tomography (CT) has developed a well-recognised role within paediatric uroradiology, especially in imaging of trauma, malignancy (in particular Wilms' tumour), atypical infection, and congenital urogenital abnormalities. CT can also be used for problem solving in nephrolithiasis and renal transplant assessment. These applications are illustrated and discussed, with an emphasis on particular information that can be gained from the CT study.

  5. Application of neutron computed tomography in the geosciences

    OpenAIRE

    Wilding, M; Shields, K.; Lesher, C. E.

    2005-01-01

    A research program that applies neutron computed tomography (CT) to geological problems has been developed at the McClellan Nuclear Radiation Center (UCD-MNRC) owned and operated by the University of California, Davis (UCD-MNRC). The high penetration of neutrons, their sensitivity to light elements, and their special sensitivity to hydrogen (in water or organic materials) make them an ideal tool for non-destructive examination of complex materials of geological interest. There are four resear...

  6. Fast neutron computed tomography with TV imaging at YAYOI

    International Nuclear Information System (INIS)

    A highly sensitive scintillation converter was used for the fast neutron television (FNTV) method. We examined the fast neutron computed tomography (FNCT) using the television (TV) method and evaluated the total CT imaging system by the modulation transfer function (MTF). The MTF evaluation showed the spatial resolution to be 1.4 mm. This was two or three times larger than the pixel size. The spatial resolution was restricted by pixel size in the present FNTV-CT system. (orig.)

  7. Establishing normal reference values in quantitative computed tomography of emphysema

    OpenAIRE

    Smith, Benjamin M.; Barr, R Graham

    2013-01-01

    Quantitative computed tomography (QCT) can provide reliable and valid measures of lung structure and volumes. Similar to lung function and volumes measured by spirometry, lung measures obtained by QCT vary by demographic and anthropomorphic factors including sex, race/ethnicity and height in asymptomatic non-smokers. Hence, some accounting for these factors is necessary to define abnormal from normal QCT values and disease severity. Similar to spirometry and cardiac volumes, prediction equati...

  8. Use of dentomaxillofacial cone beam computed tomography in dentistry

    OpenAIRE

    KAMBUROĞLU, Kıvanç

    2015-01-01

    Cone-beam computed tomography (CBCT) was developed and introduced specifically for dento-maxillofacial imaging. CBCT possesses a number of advantages over medical CT in clinical practice, such as lower effective radiation doses, lower costs, fewer space requirements, easier image acquisition, and interactive display modes such as mutiplanar reconstruction that are applicable to maxillofacial imaging. However, the disadvantages of CBCT include higher doses than two-dimensional imaging; the ina...

  9. Quantitative computed tomography imaging of airway remodeling in severe asthma

    OpenAIRE

    Grenier, Philippe A.; Fetita, Catalin I.; Brillet, Pierre-Yves

    2016-01-01

    Asthma is a heterogeneous condition and approximately 5–10% of asthmatic subjects have severe disease associated with structure changes of the airways (airway remodeling) that may develop over time or shortly after onset of disease. Quantitative computed tomography (QCT) imaging of the tracheobronchial tree and lung parenchyma has improved during the last 10 years, and has enabled investigators to study the large airway architecture in detail and assess indirectly the small airway structure. ...

  10. An Evaluation of a Prototype Proton Computed Tomography Scanner

    OpenAIRE

    Plautz, Tia Elizabeth

    2016-01-01

    Since the 1990s, the number of clinical proton therapy facilities around the world has been growing exponentially. Because of this, and the lack of imaging support for proton therapy in the treatment room, a renewed interest in proton radiography and computed tomography (CT) has emerged. This imaging modality was largely abandoned in the 1970s and '80s in favor of the already successful x-ray CT, for reasons including long acquisition times and inadequate spatial resolution. Protons are parti...

  11. Computed tomography in patients with Ehlers-Danlos syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Hagino, Hiroshi; Sugitani, Akitoshi; Eda, Isematsu; Takashima, Sachio; Takeshita, Kenzo

    1985-09-01

    Three patients with Ehlers-Danlos syndrome were reported. Unusual findings on computed tomography were seen in two of the three patients. One case showed peculiar and marked dilatation of the 4th ventricle, supracerebellar cistern and lateral ventricle. The other case presented disproportionate enlargement of the anterior horn of the lateral ventricle. These CT findings in the two patients suggest that developmental abnormalities may constitute a structural defect.

  12. Use of Cone Beam Computed Tomography in Endodontics

    Directory of Open Access Journals (Sweden)

    William C. Scarfe

    2009-01-01

    Full Text Available Cone Beam Computed Tomography (CBCT is a diagnostic imaging modality that provides high-quality, accurate three-dimensional (3D representations of the osseous elements of the maxillofacial skeleton. CBCT systems are available that provide small field of view images at low dose with sufficient spatial resolution for applications in endodontic diagnosis, treatment guidance, and posttreatment evaluation. This article provides a literature review and pictorial demonstration of CBCT as an imaging adjunct for endodontics.

  13. Role of computed tomography in the study of vascular pathology

    Energy Technology Data Exchange (ETDEWEB)

    Procacci, C.; Bicego, E.; Bergamo, I.A. and others

    1988-01-01

    The most important indications to the use of computed tomography (CT) in the study of vascular pathology are considered. They may be divided as follows: 1) demonstration of vascular involvement by thoraco-abdominal neoplasms; 2) differential diagnosis between primary vascular and extra-vascular pathology; 3) assessment of primary arterial pathology. For each group, those pathologies are considered, for which CT plays a fundamental role.

  14. Abdominal Computed Tomography Findings of Malaria Infection with Plasmodium vivax

    OpenAIRE

    Kim, Eun Mi; Cho, Hyeon Je; Cho, Chong Rae; Kwak, Yee Gyung; Kim, Mi Young; Cho, Yun Ku

    2010-01-01

    Abdominal computed tomography (CT) findings of malaria are not well-known even though malaria is a serious infectious disease. To identify abdominal CT findings, we selected 34 of 405 patients who had a positive peripheral blood smear for Plasmodium vivax and had underwent abdominal CT as the malaria group. We also selected 80 patients who had fever and a negative peripheral blood smear as the control group and 120 healthy people as the normal group. We reviewed and analyzed their medical rec...

  15. Computed tomography changes following cryotherapy for hepatic cancer

    International Nuclear Information System (INIS)

    Encouraging survival and tumour marker results have been described in patients where the focally destructive technique, hepatic cryotherapy, is used to treat primary and secondary hepatic malignancy. Radiology allows assessment of the cryotherapy procedure and follow-up treatment. This paper aims to review and describe the appearance of hepatic cryotherapy by computed tomography which allows assessment of the adequacy of surgical technique and offers the ability to identify recurrences that may be suitable for further treatment

  16. Computed tomography changes following cryotherapy for hepatic cancer

    Energy Technology Data Exchange (ETDEWEB)

    King, J.; Morris, D. L. [University of NSW, Sydney (Australia). Department of Surgery; Glenn, D. [St George Hospital, Kogarah, Sydney (Australia). Department of Radiology

    1997-05-01

    Encouraging survival and tumour marker results have been described in patients where the focally destructive technique, hepatic cryotherapy, is used to treat primary and secondary hepatic malignancy. Radiology allows assessment of the cryotherapy procedure and follow-up treatment. This paper aims to review and describe the appearance of hepatic cryotherapy by computed tomography which allows assessment of the adequacy of surgical technique and offers the ability to identify recurrences that may be suitable for further treatment. 11 refs., 1 tab., 9 figs.

  17. Use of Cone Beam Computed Tomography in Endodontics

    OpenAIRE

    Scarfe, William C.; Levin, Martin D.; David Gane; Allan G. Farman

    2009-01-01

    Cone Beam Computed Tomography (CBCT) is a diagnostic imaging modality that provides high-quality, accurate three-dimensional (3D) representations of the osseous elements of the maxillofacial skeleton. CBCT systems are available that provide small field of view images at low dose with sufficient spatial resolution for applications in endodontic diagnosis, treatment guidance, and posttreatment evaluation. This article provides a literature review and pictorial demonstration of CBCT as an imagin...

  18. Multidetector computed tomography of the coronary arteries - pictorial essay

    International Nuclear Information System (INIS)

    Multidetector computed tomography (MDCT) is being used more frequently for the detection of atherosclerotic coronary artery disease (CAD). MDCT allows for very rapid image acquisition with little motion artifact, resulting in the ability to quantitate calcified atherosclerotic plaque. Congenital coronary artery anomalies are readily identified using this technique. A key advantage is the noninvasiveness of the study, with no intravascular contrast media needed. Knowledge of coronary artery anatomy as well as of the potential pitfalls is required. (author)

  19. Computed Tomography Inspection and Analysis for Additive Manufacturing Components

    Science.gov (United States)

    Beshears, Ronald D.

    2016-01-01

    Computed tomography (CT) inspection was performed on test articles additively manufactured from metallic materials. Metallic AM and machined wrought alloy test articles with programmed flaws were inspected using a 2MeV linear accelerator based CT system. Performance of CT inspection on identically configured wrought and AM components and programmed flaws was assessed using standard image analysis techniques to determine the impact of additive manufacturing on inspectability of objects with complex geometries.

  20. Thermal Neutron Computed Tomography of Soil Water and Plant Roots

    OpenAIRE

    Leanne G. Tumlinson; Hungyuan Liu; Wendy K. Silk; Hopmans, Jan W.

    2007-01-01

    Neutron radiography is a noninvasive imaging technique that measures the attenuation of thermal neutrons, as is done with x-ray and γ-ray radiography, to characterize the internal composition of materials. Neutron and x-ray imaging are complementary techniques, with neutron imaging especially well suited for materials containing H atoms and other low-atomic-weight attenuating materials. Although neutron computed tomography (NCT) techniques are routinely used in engineering, relatively little ...

  1. Computed tomography in complex fractures of the ankle joint

    Energy Technology Data Exchange (ETDEWEB)

    Friedburg, H.; Wimmer, B.; Hendrich, V.; Riede, U.N.

    1983-09-01

    Diagnostic value of conventional roentgen technique and computed tomography is proofed by examination of 50 patients with sprain fractures of the ankle joint. The dimension of destruction of the distal tibial joint surface is better documented by CT than by other radiological techniques. Additional informations like multiframentation of the distal tibia or evaluation of reposition impediment are found more frequently by CT. Therefore indication and planning of the traumatherapy can be assessed better by the traumatologist.

  2. [Multislice spiral computed tomography in the diagnosis of osteomyelitis].

    Science.gov (United States)

    Egorova, E A; Zorina, I S; Sangaeva, L M

    2010-01-01

    This paper deals with the results of a radiation study in 34 patients with the clinical manifestations of maxillofacial osteomyelitides. It describes the radiation semiotics of changes occurring in the bone and its surrounding soft tissues of the maxillofacial region in different phases of osteomyelitis. Comparative analysis of orthopantograms and images obtained by multislice spiral computed tomography revealed the benefits of the latter in detecting soft tissue changes and subtle bone alterations.

  3. Use of Positron Emission Tomography/Computed Tomography in Radiation Treatment Planning for Lung Cancer

    OpenAIRE

    Kezban Berberoğlu

    2016-01-01

    Radiotherapy (RT) plays an important role in the treatment of lung cancer. Accurate diagnosis and staging are crucial in the delivery of RT with curative intent. Target miss can be prevented by accurate determination of tumor contours during RT planning. Currently, tumor contours are determined manually by computed tomography (CT) during RT planning. This method leads to differences in delineation of tumor volume between users. Given the change in RT tools and methods due to rapidly ...

  4. SADMFR Guidelines for the Use of Cone-Beam Computed Tomography/Digital Volume Tomography

    OpenAIRE

    Dula, Karl; Benic, Goran I; Bornstein, Michael; Dagassan-Berndt, Dorothea; Filippi, Andreas; Hicklin, Stefan; Kissling-Jeger, Franziska; Luebbers, Heinz-Theo; Sculean, Anton; Sequeira-Byron, Patrick; Walter, Clemens; Zehnder, Matthias

    2015-01-01

    In 2011, the first consensus conference on guidelines for the use of cone-beam computed tomography (CBCT) was convened by the Swiss Society of Dentomaxillofacial Radiology (SGDMFR). This conference covered topics of oral and maxillofacial surgery, temporomandibular joint dysfunctions and disorders, and orthodontics. In 2014, a second consensus conference was convened on guidelines for the use of CBCT in endodontics, periodontology, reconstructive dentistry and pediatric dentistry. The guideli...

  5. 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

    Institute of Scientific and Technical Information of China (English)

    宋世祥

    2014-01-01

    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

  6. Helical computed tomography in the assessment of abdominal aortic pathology

    Energy Technology Data Exchange (ETDEWEB)

    Vicaretti, M.; Young, N.; Jenkins, J.; Fletcher, J. [Westmead Hospital, Westmead, NSW (Australia)

    1997-05-01

    A pilot study was undertaken to evaluate the role of helical computed tomography in the assessment of abdominal aortic pathology. A total of 17 patients underwent intra-arterial digital subtraction angiography (IADSA) and helical computed tomography, with eight patients undergoing subsequent operative intervention. A comparison of radiological findings between IADSA and helical computed tomography (CT) was made and, where applicable, a comparison was made with operative findings. Pathology included abdominal aortic aneurysm (AAA) (n=12), thoraco abdominal aneurysm (n=2) and dissection (n=1), graft distension following AAA repair (n=1) and plaque haemorrhage in the distal aorta following percutaneous transluminal angioplasty (PTA) of the iliac artery (n=1). Planned operative management as based on pre-operative helical CT imaging findings, in particular with reference to the type of graft used (straight or bifurcated) was not changed at operation. Our findings on helical CT in regards to AAA, thoraco-abdominal aneurysm and dissection correlated well with angiography and surgery findings. (authors). 26 refs., 2 tabs., 5 figs.

  7. Efficacy of multislice computed tomography for gastroenteric and hepatic surgeries

    Institute of Scientific and Technical Information of China (English)

    Hiroshi Ohtani; Mitsuo Tsubakimoto; Hidemi Kawajiri; Yuichi Arimoto; Koichi Ohno; Yasuhisa Fujimoto; Hiroko Oba; Kenji Adachi; Masaya Hirano; Shoichi Terakawa

    2005-01-01

    AIM: To determine the efficacy of multislice CT for gastroenteric and hepatic surgery.METHODS: Dual-phase helical computed tomography was performed in 50 of 51 patients who underwent gastroenteric and hepatic surgeries. Twenty-eight, eighteen and four patients suffering from colorectal cancer, gastric cancer,and liver cancer respectively underwent colorectal surgery (laparoscopic surgery: 6 cases), gastrectomy, and hepatectomy. Three-dimensional computed tomography imaging of the inferior mesenteric artery, celiac artery and hepatic artery was performed. And in the follow-up examination of postoperative patients, multiplanar reconstruction image was made in case of need.RESULTS: Scans in 50 patients were technically satisfactory and included in the analysis. Depiction of major visceral arteries, which were important for surgery and other treatments, could be done in all patients.Preoperative visualization of the left colic artery and sigmoidal arteries, the celiac artery and its branches, and hepatic artery was very useful to lymph node dissection,the planning of a reservoir and hepatectomy. And multiplanar reconstruction image was helpful to diagnosis for the postoperative follow-up of patients.CONCLUSION: Three-dimensional volume rendering or multiplanar reconstruction imaging performed by multislice computed tomography was very useful for gastroenteric and hepatic surgeries.

  8. Anatomical structure of lingual foramen in cone beam computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Ki, Min Woo; Hwang, Eui Hwan; Lee, Sang Rae [Kyunghee University College of Medicine, Seoul (Korea, Republic of)

    2004-07-15

    To evaluate whether cone beam computed tomography can depict the distribution, position, frequency, relative vertical dimension, and the diameter of the lingual foramen and direction of lingual bone canal. Cone beam computed tomography of mandible was performed on 25 males and 25 females with no history of any orthodontic treatments or any other dental surgeries. A statistical comparison was done on the mean values of males and females. In the location and distribution of lingual foramina, median lingual foramen was found in all subjects and lateral lingual foramen in 58%. In the lateral lingual foramen, bilateral type was found in 28% and unilateral type in 30%. In the number of lingual foramina, median lingual foramen had two foramina and lateral lingual foramen had one foramen, mostly. In the relative mean vertical dimension of lingual foramina, median lingual foramen was 0.03 {+-} 0.08, and both lateral lingual foramina was 0.20 {+-} 0.04. The mean diameter of lingual foramina, median lingual foramen was 0.9 mm {+-} 0.28, right lateral lingual foramen was 0.92 mm {+-} 0.23, and left lateral lingual foramen was 0.88 mm {+-} 0.27. The most frequent direction of the lingual bone canals, median lingual bone canal proceeded in anteroinferior direction and lateral lingual bone canal in anterosuperolateral direction. Cone beam computed tomography can be helpful for surgery and implantation on the mandibular area. Radiologist should be aware of this anatomical feature and its possible implications.

  9. Multidetector computed tomography in the preoperative staging of gastric adenocarcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Barros, Ricardo Hoelz de Oliveira; Penachim, Thiago Jose; Martins, Daniel Lahan; Andreollo, Nelson Adami; Caserta, Nelson Marcio Gomes, E-mail: rhobarros@hotmail.com [Universidade Estadual de Campinas (UNICAMP), Campinas, SP (Brazil)

    2015-03-15

    Objective: To evaluate the role of multidetector computed tomography in the preoperative investigation of tumor invasion depth and lymph node and metastatic involvement according to the TNM classification, in patients with gastric adenocarcinoma. Materials and Methods: Fifty-four patients with biopsy-confirmed gastric cancer underwent preoperative staging with 64-channel multidetector computed tomography. Two independent radiologists analyzed the images and classified the findings. Sensitivity, specificity, accuracy and overall accuracy were calculated for each observer. The interobserver agreement was also evaluated. Results: The accuracy in the classification of categories T ranged from 74% to 96% for observer 1 and from 80% to 92% for observer 2. The overall accuracy was 70% for both observers. The weighted kappa index was 0.75, consistent with a significant interobserver agreement. The accuracy in the classification of lymph node involvement (category N) ranged from 55% to 79% for observer 1 and from 73% to 82% for observer 2. The evaluation of metastatic involvement showed an overall accuracy of 89.6% for both observers. Conclusion: 64-channel multidetector computed tomography demonstrated clinically relevant accuracy in the preoperative staging of gastric adenocarcinoma as regards invasion depth (T category) and metastatic involvement (M category). (author)

  10. Correlation of echoencephalography and computer tomography in expansive brain lesions

    International Nuclear Information System (INIS)

    50 patients with confirmed expansive intracranial processes were examined by two methods - echoencephalography and computer tomography. The deviation of the middle echo from two points on the calva and the corresponding deviation of septum pellucidum and epiphysis according to the computer tomography examination were compared. The findings are not quite identical. As a rule there is a minor deviation in echoencephalography examinations as compared with the deviation of corresponding structures according to computer tomography, the difference, however, does not exceed 3 mm. Echoencephalography examinations made at two different points on the calva increase the accuracy and sensitivity of the finding. In expansive processes with a more lateral and posterior localization we usually do not only find greater shifts of the echoencephalography in the anterior as well as posterior temporal region but also an increased difference between the two deviations. Despite the use of most up-to-date diagnostic methods echoencephalography remains a rapid, low-cost and unpretentious method in neurology and neurosurgery. It provides, however, only information for orientation and is biassed with an 5 to 8% error. (author)

  11. Dosimetry in abdominal imaging by 6-slice computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Rodrigues, Sonia Isabel [Hospital de Faro, EPE (Portugal); Abrantes, Antonio Fernando; Ribeiro, Luis Pedro; Almeida, Rui Pedro Pereira [University of Algarve (Portugal). School of Health. Dept. of Radiology

    2012-11-15

    Objective: To determine the effective dose in abdominal computed tomography imaging and to study the influence of patients' characteristics on the received dose. Materials and Methods: Dose values measurements were performed with an ionization chamber on phantoms to check the agreement between dose values and those presented by the computed tomography apparatus, besides their compliance with the recommended reference dose levels. Later, values of dose received by physically able patients submitted to abdominal computed tomography (n = 100) were measured and correlated with their anthropometric characteristics. Finally, the dose to organs was simulated with the Monte Carlo method using the CT-Expo V 1.5 software, and the effect of automatic exposure control on such examinations. Results: The main characteristics directly influencing the dose include the patients' body mass, abdominal perimeter and body mass index, whose correlation is linear and positive. Conclusion: The radiation dose received from abdominal CT scans depends on some patient's characteristics, and it is important to adjust the acquisition parameters to their dimensions (author)

  12. Hepatic hemangiomas as diagnosed by ultrasonography and computed tomography

    International Nuclear Information System (INIS)

    A total of 62 cases where the clinical diagnosis of hepatic hemangioma had been established during the period between 1981 and 1983 on the basis of computed tomography and sonography were subjected to retrospective analysis with the aim of evaluating the diagnostic reliability of these two methods. In 29 patients a typical distribution pattern of the contrast medium gave irrefutable evidence of the disease. Hemangiomas were predicted from the results of computed tomography for a further 5 patients with less revealing distribution patterns, although in 4 among these the preliminary diagnosis of hemangioma was disproved by additional diagnostic procedures (scintigraphy, laparoscopy, surgery and biopsy). Out of 16 patients, in which the hemangiomas were diagnosed from the typical patterns created by the contrast medium on the CT scans, 11 showed sonographic findings to confirm the presence of such tumours. This retrospective analysis showed that a correct and positive diagnosis could be established in no more than 7 patients on the basis of sonography alone, while 6 such diagnoses were definitely proven to be false-positive. As regards diagnostic accuracy, sonography clearly compares unfavourably with computed tomography. It may offer some advantages inasmuch as it requires no radiation exposure, is non-invasive and, last not least, less costly. (ECB)

  13. Clinical utility of dental cone-beam computed tomography: current perspectives

    Directory of Open Access Journals (Sweden)

    Jaju PP

    2014-04-01

    Full Text Available Prashant P Jaju,1 Sushma P Jaju21Oral Medicine and Radiology, 2Conservative Dentistry and Endodontics, Rishiraj College of Dental Sciences and Research Center, Bhopal, IndiaAbstract: Panoramic radiography and computed tomography were the pillars of maxillofacial diagnosis. With the advent of cone-beam computed tomography, dental practice has seen a paradigm shift. This review article highlights the potential applications of cone-beam computed tomography in the fields of dental implantology and forensic dentistry, and its limitations in maxillofacial diagnosis.Keywords: dental implants, cone-beam computed tomography, panoramic radiography, computed tomography

  14. Accuracy of measurement of pulmonary emphysema with computed tomography: relevant points

    Energy Technology Data Exchange (ETDEWEB)

    Hochhegger, Bruno, E-mail: brunohochhegger@googlemail.co [Hospital Moinhos de Vento, Porto Alegre, RS (Brazil); Marchiori, Edson [Universidade Federal Fluminense (UFF), Niteroi, RJ (Brazil). Dept. de Radiologia; Irion, Klaus L. [Liverpool Heart and Chest Hospital, Liverpool (United Kingdom); Oliveira, Hugo [Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS (Brazil)

    2010-07-15

    Some technical aspects should be taken into consideration in order to guarantee the reliability of the assessment of pulmonary emphysema with lung computed tomography densitometry. Changes in lung density associated with variations in lungs inspiratory and expiratory levels, computed tomography slice thickness, reconstruction algorithm and type of computed tomography apparatus make tomographic comparisons more difficult in follow-up studies of pulmonary emphysema. Nevertheless, quantitative computed tomography has replaced the visual assessment competing with pulmonary function tests as a sensitive method to measure pulmonary emphysema. The present review discusses technical variables of lung computed tomography and their influence on measurements of pulmonary emphysema. (author)

  15. Accuracy of measurement of pulmonary emphysema with computed tomography: relevant points

    International Nuclear Information System (INIS)

    Some technical aspects should be taken into consideration in order to guarantee the reliability of the assessment of pulmonary emphysema with lung computed tomography densitometry. Changes in lung density associated with variations in lungs inspiratory and expiratory levels, computed tomography slice thickness, reconstruction algorithm and type of computed tomography apparatus make tomographic comparisons more difficult in follow-up studies of pulmonary emphysema. Nevertheless, quantitative computed tomography has replaced the visual assessment competing with pulmonary function tests as a sensitive method to measure pulmonary emphysema. The present review discusses technical variables of lung computed tomography and their influence on measurements of pulmonary emphysema. (author)

  16. Multi-scale analysis of lung computed tomography images

    CERN Document Server

    Gori, I; Fantacci, M E; Martinez, A Preite; Retico, A; De Mitri, I; Donadio, S; Fulcheri, C; Gargano, G; Magro, R; Santoro, M; Stumbo, S; 10.1088/1748-0221/2/09/P09007

    2009-01-01

    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.

  17. Multi-scale analysis of lung computed tomography images

    CERN Document Server

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

    2007-01-01

    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.

  18. Computed tomography angiography and perfusion to assess coronary artery stenosis causing perfusion defects by single photon emission computed tomography

    DEFF Research Database (Denmark)

    Rochitte, Carlos E; George, Richard T; Chen, Marcus Y;

    2014-01-01

    AIMS: To evaluate the diagnostic power of integrating the results of computed tomography angiography (CTA) and CT myocardial perfusion (CTP) to identify coronary artery disease (CAD) defined as a flow limiting coronary artery stenosis causing a perfusion defect by single photon emission computed...... tomography (SPECT). METHODS AND RESULTS: We conducted a multicentre study to evaluate the accuracy of integrated CTA-CTP for the identification of patients with flow-limiting CAD defined by ≥50% stenosis by invasive coronary angiography (ICA) with a corresponding perfusion deficit on stress single photon...... myocardial infarction, the AUC was 0.90 (95% CI: 0.87-0.94) and in patients without prior CAD the AUC for combined CTA-CTP was 0.93 (95% CI: 0.89-0.97). For the combination of a CTA stenosis ≥50% stenosis and a CTP perfusion deficit, the sensitivity, specificity, positive predictive, and negative predicative...

  19. Nonoperative treatment of splenic trauma: usefulness of computed tomography

    International Nuclear Information System (INIS)

    Objective: to report the results of use of conservative treatment in patients with splenic trauma and to emphasize the usefulness of computed tomography in these cases. Material and method: sixty-nine cases of pediatric patients with blunt abdominal trauma seen from from January 2001 to June 2004 at the level I trauma center were retrospectively studied. Forty-four of these patients were submitted to nonoperative treatment and the clinical follow-up was performed by computerized tomography. All patients had been diagnosed with splenic injury by computerized tomography.Results: the causes of the injuries were motor vehicle accident in 12 (27.2%) patients, bicycle accident in nine (20.4%) patients, and falls in 23 (52.2%) patients. Two (3.7%) patients died from associated injuries. The mean duration of hospital stay was six days. The mean age of the patients was nine years. Conclusion: conservative treatment for blunt splenic trauma is performed with the aim of reducing costs and risks for the patients, and computerized tomography should be routinely used. No posterior complications were observed in this approach. (author)

  20. Observation of the pulp horn by swept source optical coherence tomography and cone beam computed tomography

    Science.gov (United States)

    Iino, Yoshiko; Yoshioka, Toshihiko; Hanada, Takahiro; Ebihara, Arata; Sunakawa, Mitsuhiro; Sumi, Yasunori; Suda, Hideaki

    2015-02-01

    Cone-beam computed tomography (CBCT) is one of the most useful diagnostic techniques in dentistry but it involves ionizing radiation, while swept source optical coherence tomography (SS-OCT) has been introduced recently as a nondestructive, real-time, high resolution imaging technique using low-coherence interferometry, which involves no ionizing radiation. The purpose of this study was to evaluate the ability of SS-OCT to detect the pulp horn (PH) in comparison with that of CBCT. Ten extracted human mandibular molars were used. After horizontally removing a half of the tooth crown, the distance from the cut dentin surface to PH was measured using microfocus computed tomography (Micro CT) (SL) as the gold standard, by CBCT (CL) and by SS-OCT (OL). In the SS-OCT images, only when PH was observed beneath the overlying dentin, the distance from the cut dentin surface to PH was recorded. If the pulp was exposed, it was defined as pulp exposure (PE). The results obtained by the above three methods were statistically analyzed by Spearman's rank correlation coefficient at a significance level of p images correlated closely with CBCT images, suggesting that SS-OCT can be a useful tool for the detection of PH.

  1. Computed tomography and (18)F-fluorodeoxyglucose positron emission tomography/computed tomography findings in adrenal candidiasis and histoplasmosis: two cases.

    Science.gov (United States)

    Altinmakas, Emre; Guo, Ming; Kundu, Uma R; Habra, Mouhammed Amir; Ng, Chaan

    2015-01-01

    We report the contrast-enhanced computed tomography (CT) and (18)F-fluorodeoxyglucose positron emission tomography findings in adrenal histoplasmosis and candidiasis. Both demonstrated bilateral hypermetabolic heterogeneous adrenal masses with limited wash-out on delayed CT. Adrenal candidiasis has not been previously reported, nor have the CT wash-out findings in either infection. The adrenal imaging findings are indistinguishable from malignancy, which is more common; but in this setting, physicians should be alert to the differential diagnosis of fungal infections, since it can be equally deadly.

  2. Paracoccidioidomycosis: High-resolution computed tomography-pathologic correlation

    International Nuclear Information System (INIS)

    Objective: The purpose of this study was to describe the high-resolution computed tomography (HRCT) features of pulmonary paracoccidioidomycosis and to correlate them with pathologic findings. Methods: The study included 23 adult patients with pulmonary paracoccidioidomycosis. All patients had undergone HRCT, and the images were retrospectively analyzed by two chest radiologists, who reached decisions by consensus. An experienced lung pathologist reviewed all pathological specimens. The HRCT findings were correlated with histopathologic data. Results: The predominant HRCT findings included areas of ground-glass opacities, nodules, interlobular septal thickening, airspace consolidation, cavitation, and fibrosis. The main pathological features consisted of alveolar and interlobular septal inflammatory infiltration, granulomas, alveolar exudate, cavitation secondary to necrosis, and fibrosis. Conclusion: Paracoccidioidomycosis can present different tomography patterns, which can involve both the interstitium and the airspace. These abnormalities can be pathologically correlated with inflammatory infiltration, granulomatous reaction, and fibrosis.

  3. Paracoccidioidomycosis: High-resolution computed tomography-pathologic correlation

    Energy Technology Data Exchange (ETDEWEB)

    Marchiori, Edson, E-mail: edmarchiori@gmail.com [Fluminense Federal University, Rio de Janeiro (Brazil); Federal University of Rio de Janeiro, Rio de Janeiro (Brazil); Valiante, Paulo Marcos, E-mail: valiante.rlk@terra.com.br [Federal University of Rio de Janeiro, Rio de Janeiro (Brazil); Mano, Claudia Mauro, E-mail: cacaumano@gmail.com [Fluminense Federal University, Rio de Janeiro (Brazil); Zanetti, Glaucia, E-mail: glauciazanetti@gmail.com [Federal University of Rio de Janeiro, Rio de Janeiro (Brazil); Petropolis Faculty of Medicine, Rio de Janeiro (Brazil); Escuissato, Dante L., E-mail: danteescuissato@gmail.com [Federal University of Parana, Curitiba (Brazil); Souza, Arthur Soares, E-mail: asouzajr@gmail.com [Faculty of Medicine of Rio Preto, Sao Paulo (Brazil); Capone, Domenico, E-mail: domenicocap@gmail.com [Federal University of Rio de Janeiro, Rio de Janeiro (Brazil)

    2011-01-15

    Objective: The purpose of this study was to describe the high-resolution computed tomography (HRCT) features of pulmonary paracoccidioidomycosis and to correlate them with pathologic findings. Methods: The study included 23 adult patients with pulmonary paracoccidioidomycosis. All patients had undergone HRCT, and the images were retrospectively analyzed by two chest radiologists, who reached decisions by consensus. An experienced lung pathologist reviewed all pathological specimens. The HRCT findings were correlated with histopathologic data. Results: The predominant HRCT findings included areas of ground-glass opacities, nodules, interlobular septal thickening, airspace consolidation, cavitation, and fibrosis. The main pathological features consisted of alveolar and interlobular septal inflammatory infiltration, granulomas, alveolar exudate, cavitation secondary to necrosis, and fibrosis. Conclusion: Paracoccidioidomycosis can present different tomography patterns, which can involve both the interstitium and the airspace. These abnormalities can be pathologically correlated with inflammatory infiltration, granulomatous reaction, and fibrosis.

  4. Computed Tomography Imaging of the Topographical Anatomy of Canine Prostate

    International Nuclear Information System (INIS)

    AIM: To investigate the topographical anatomy of canine prostate gland by computed tomography (CT) for diagnostic imaging purposes. ÐœATERIAL AND METHODS: Seven clinically healthy mongrel male dogs at the age of 3−4 years and body weight of 10−15 kg were submitted to transverse computerized axial tomography (CAT) with cross section thickness of 5 mm. RESULTS: The CT image of canine prostate is visualized throughout the scans of the pelvis in the planes through the first sacral vertebra (S1) dorsally; the bodies of iliac bones laterally and cranially to the pelvic brim (ventrally). The body of prostate appears as an oval homogenous relatively hypo dense finding with soft tissue density. The gland is well differentiated from the adjacent soft tissues. CONCLUSION: By means of CT, the cranial part of prostate gland in adult dogs aged 3−4 years exhibited an abdominal localization. (author)

  5. A review of X-ray computed axial tomography

    International Nuclear Information System (INIS)

    A review of Computed axial tomography (CAT) scanning literature outlining the theoretical and practical aspects of this technique with application in both medical diagnosis and industrial non-destructive inspection (NDI) is presented. Practical aspects of CAT scanning discussed include : radiation sources, currently available spatial and contrast resolution limits and the evolution of the computerized tomography (CT) system. It was found that monochromatic gamma rays are preferred to X-rays, especially for very high density materials, and that in medical CAT scanning, the special resolution is only, 0.5 mm while spatial resolutions of less than 50μm have been achieved in NDI. An increased number of scientific and industrial applications are anticipated (e.g. for studying sintering reactions), as the capital cost of CAT scanning decreased. 13 refs., 9 figs., 2 tabs

  6. Combined positron emission tomography and computed tomography to visualize and quantify fluid flow in sedimentary rocks

    Science.gov (United States)

    Fernø, M. A.; Gauteplass, J.; Hauge, L. P.; Abell, G. E.; Adamsen, T. C. H.; Graue, A.

    2015-09-01

    Here we show for the first time the combined positron emission tomography (PET) and computed tomography (CT) imaging of flow processes within porous rocks to quantify the development in local fluid saturations. The coupling between local rock structure and displacement fronts is demonstrated in exploratory experiments using this novel approach. We also compare quantification of 3-D temporal and spatial water saturations in two similar CO2 storage tests in sandstone imaged separately with PET and CT. The applicability of each visualization technique is evaluated for a range of displacement processes, and the favorable implementation of combining PET/CT for laboratory core analysis is discussed. We learn that the signal-to-noise ratio (SNR) is over an order of magnitude higher for PET compared with CT for the studied processes.

  7. Reconstruction Algorithms for Positron Emission Tomography and Single Photon Emission Computed Tomography and their Numerical Implementation

    CERN Document Server

    Fokas, A S; Marinakis, V

    2004-01-01

    The modern imaging techniques of Positron Emission Tomography and of Single Photon Emission Computed Tomography are not only two of the most important tools for studying the functional characteristics of the brain, but they now also play a vital role in several areas of clinical medicine, including neurology, oncology and cardiology. The basic mathematical problems associated with these techniques are the construction of the inverse of the Radon transform and of the inverse of the so called attenuated Radon transform respectively. We first show that, by employing mathematical techniques developed in the theory of nonlinear integrable equations, it is possible to obtain analytic formulas for these two inverse transforms. We then present algorithms for the numerical implementation of these analytic formulas, based on approximating the given data in terms of cubic splines. Several numerical tests are presented which suggest that our algorithms are capable of producing accurate reconstruction for realistic phanto...

  8. Unusual case of infantile fibrosarcoma evaluated on F-18 fluorodeoxyglucose positron emission tomography-computed tomography.

    Science.gov (United States)

    Bedmutha, Akshay; Singh, Natasha; Shivdasani, Divya; Gupta, Nitin

    2016-01-01

    Infantile fibrosarcoma (IFS) is a rare soft-tissue sarcoma originating from extremities and occasionally from axial soft tissue. The prognosis is good with favorable long-term survival. It is rarely metastasizing tumor, the chances being lesser with IFS originating from extremities. Use of neoadjuvant chemotherapy (NACT) as a treatment regime further reduces the chances of local relapse and distant metastasis. The organs commonly affected in metastatic IFS are lungs and lymph nodes. We report an unusual case of an IFS originating from extremity, which received NACT, yet presented with an early metastatic disease involving soft tissues and sparing lungs and lymph nodes, as demonstrated on fluorodeoxyglucose positron emission tomography-computed tomography. PMID:27385891

  9. Quantitative cone beam X-ray luminescence tomography/X-ray computed tomography imaging

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Dongmei; Zhu, Shouping, E-mail: zhusp2009@gmail.com; Chen, Xueli; Chao, Tiantian; Cao, Xu; Zhao, Fengjun; Huang, Liyu; Liang, Jimin [Engineering Research Center of Molecular and Neuro Imaging of Ministry of Education and School of Life Science and Technology, Xidian University, Xi' an, Shaanxi 710071 (China)

    2014-11-10

    X-ray luminescence tomography (XLT) is an imaging technology based on X-ray-excitable materials. The main purpose of this paper is to obtain quantitative luminescence concentration using the structural information of the X-ray computed tomography (XCT) in the hybrid cone beam XLT/XCT system. A multi-wavelength luminescence cone beam XLT method with the structural a priori information is presented to relieve the severe ill-posedness problem in the cone beam XLT. The nanophosphors and phantom experiments were undertaken to access the linear relationship of the system response. Then, an in vivo mouse experiment was conducted. The in vivo experimental results show that the recovered concentration error as low as 6.67% with the location error of 0.85 mm can be achieved. The results demonstrate that the proposed method can accurately recover the nanophosphor inclusion and realize the quantitative imaging.

  10. Fasciola Hepatica Mimicking Malignancy on 18F-Fluorodeoxyglucose-Positron Emission Tomography/Computed Tomography

    Directory of Open Access Journals (Sweden)

    Erdem Sürücü

    2016-10-01

    Full Text Available A 48-year-old female with complaints of gastrointestinal symptoms such as abdominal pain, fatigue, vomiting, nausea, and weight loss was diagnosed with neuroendocrine tumor after removal of a 2 mm lesion from the stomach with endoscopic biopsy. Her magnetic resonance imaging that was performed due to on-going symptoms showed multiple linear hypointense lesions in the liver. Positron emission tomography/computed tomography (PET/CT scan was performed for differential diagnosis, which showed high fluorodeoxyglucose (FDG uptake in these lesions. Clinical and laboratory findings revealed the final diagnosis as Fasciola hepatica. The imaging features of this case is presented to aid in differentiating this infectious disease from malignancy and avoid misdiagnosis on FDG-PET/CT.

  11. Fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography in the detection of primary pulmonary angiosarcomas

    International Nuclear Information System (INIS)

    Angiosarcoma is a malignant vascular tumor that originates from the mesenchymal cells which have undergone angioblastic differentiation. Pulmonary angiosarcomas are invariably (>90%) metastatic tumors form primaries of the skin, bone, liver, breast, or heart. Primary pulmonary angiosarcomas are exceedingly rare, with just about 20 cases being reported in the literature. We report an additional case with a brief review of the literature of a primary pulmonary angiosarcoma in a 26-year-old lady who presented with intractable hemoptysis. In addition, we highlight the potential of fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography as an important diagnostic tool in the evaluation of this tumor and thus contribute to the existing sparse literature on this fascinating yet devastating disease

  12. 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

    Energy Technology Data Exchange (ETDEWEB)

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

    2007-09-15

    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

  13. X-ray computed tomography for virtually unrolling damaged papyri

    Energy Technology Data Exchange (ETDEWEB)

    Allegra, Dario; Ciliberto, Paolo; Stanco, Filippo [Universita degli Studi di Catania, Dipartimento di Matematica ed Informatica, Catania (Italy); Ciliberto, Enrico [Universita degli Studi di Catania, Dipartimento di Scienze Chimiche, Catania (Italy); Petrillo, Giuseppe; Trombatore, Claudia [Universita degli Studi di Catania, Dipartimento di Scienze Mediche Chirurgiche e Tecnologie Avanzate, Catania (Italy)

    2016-03-15

    The regular format for ancient works of literature was the papyrus roll. Recently many efforts to perform virtual restoration of this archeological artifact have been done. In fact the case of ancient rolled papyrus is very intriguing. Old papyruses are the substrates of very important historical information, probably being the use of papyrus dated to the Pre-Dynastic Period. Papyrus degradation is often very hard so that physical unrolling is sometime absolutely impossible. In this paper, authors describe their effort in setting a new virtual restoration methodology based on software manipulation of X-ray tomographic images. A realistic model, obtained by painting a hieroglyph inscription of Thutmosis III on a papyrus substrate made by the original method described by Plinius the Elder and by pigments and binders compatible with the Egyptian use (ochers with natural glue), was made for the X-ray investigation. A GE Optima 660 64 slice was used to obtain a stack of tomographic slices of the rolled model. Each slice appears as spiral. The intensity variations along the cross-sectional result from ink on the papyrus. The files were elaborated with original software, written by the use of MATLAB high-level language, and the final result was quite similar to the radiography of the physically unrolled sheet. (orig.)

  14. X-ray computed tomography for virtually unrolling damaged papyri

    International Nuclear Information System (INIS)

    The regular format for ancient works of literature was the papyrus roll. Recently many efforts to perform virtual restoration of this archeological artifact have been done. In fact the case of ancient rolled papyrus is very intriguing. Old papyruses are the substrates of very important historical information, probably being the use of papyrus dated to the Pre-Dynastic Period. Papyrus degradation is often very hard so that physical unrolling is sometime absolutely impossible. In this paper, authors describe their effort in setting a new virtual restoration methodology based on software manipulation of X-ray tomographic images. A realistic model, obtained by painting a hieroglyph inscription of Thutmosis III on a papyrus substrate made by the original method described by Plinius the Elder and by pigments and binders compatible with the Egyptian use (ochers with natural glue), was made for the X-ray investigation. A GE Optima 660 64 slice was used to obtain a stack of tomographic slices of the rolled model. Each slice appears as spiral. The intensity variations along the cross-sectional result from ink on the papyrus. The files were elaborated with original software, written by the use of MATLAB high-level language, and the final result was quite similar to the radiography of the physically unrolled sheet. (orig.)

  15. X-ray computed tomography for virtually unrolling damaged papyri

    Science.gov (United States)

    Allegra, Dario; Ciliberto, Enrico; Ciliberto, Paolo; Petrillo, Giuseppe; Stanco, Filippo; Trombatore, Claudia

    2016-03-01

    The regular format for ancient works of literature was the papyrus roll. Recently many efforts to perform virtual restoration of this archeological artifact have been done. In fact the case of ancient rolled papyrus is very intriguing. Old papyruses are the substrates of very important historical information, probably being the use of papyrus dated to the Pre-Dynastic Period. Papyrus degradation is often very hard so that physical unrolling is sometime absolutely impossible. In this paper, authors describe their effort in setting a new virtual restoration methodology based on software manipulation of X-ray tomographic images. A realistic model, obtained by painting a hieroglyph inscription of Thutmosis III on a papyrus substrate made by the original method described by Plinius the Elder and by pigments and binders compatible with the Egyptian use (ochers with natural glue), was made for the X-ray investigation. A GE Optima 660 64 slice was used to obtain a stack of tomographic slices of the rolled model. Each slice appears as spiral. The intensity variations along the cross-sectional result from ink on the papyrus. The files were elaborated with original software, written by the use of MATLAB high-level language, and the final result was quite similar to the radiography of the physically unrolled sheet.

  16. Positron emission tomography/computed tomography predictors of overall survival in stage IIIC/IV ovarian cancer

    DEFF Research Database (Denmark)

    Risum, Signe; Loft, Annika; Engelholm, Svend Aage;

    2012-01-01

    To evaluate the role of 2-deoxy-2-(F)fluoro-D-glucose (FDG) positron emission tomography/computed tomography (PET/CT) for selecting patients with extensive ovarian cancer (OC) for neoadjuvant chemotherapy by evaluating predictors of overall survival in patients with stage IIIC/IV OC....

  17. In Vivo Treatment Sensitivity Testing With Positron Emission Tomography/Computed Tomography After One Cycle of Chemotherapy for Hodgkin Lymphoma

    DEFF Research Database (Denmark)

    Hutchings, Martin; Kostakoglu, Lale; Zaucha, Jan Maciej;

    2014-01-01

    PURPOSE: Negative [(18)F]fluorodeoxyglucose (FDG) -positron emission tomography (PET)/computed tomography (CT) after two cycles of chemotherapy indicates a favorable prognosis in Hodgkin lymphoma (HL). We hypothesized that the negative predictive value would be even higher in patients responding...

  18. F-18 fluoro-d-glucose positron emission tomography/computed tomography in a patient with corticobasal degeneration

    International Nuclear Information System (INIS)

    Corticobasal degeneration is a rare neurodegenerative disorder that often eludes clinical diagnosis. The present case shows the F-18 fluoro-d-glucose positron emission tomography/computed tomography (PET/CT) of a 62-year-old man with a progressive movement disorder with asymmetric features. PET/CT examination showed a markedly right-brain hemispheric hypometabolism also involving basal ganglia

  19. Marked uptake of fluorodeoxyglucose in a vocal cord after medialization: Acute and subacute positron emission tomography/computed tomography findings

    International Nuclear Information System (INIS)

    A 60-year-old male who underwent left upper lobectomy because of recently diagnosed lung cancer was admitted to the nuclear medicine department. A whole body fluorodeoxyglucose positron emission tomography/computed tomography (CT) that was performed for staging purposes, revealed an intense hypermetabolism in left vocal cord region corresponding with hyperdense mass-like material on CT scan

  20. Report of two cases of fluorodeoxyglucose positron emission tomography/computed tomography appearance of hibernoma: A rare benign tumor

    International Nuclear Information System (INIS)

    False-positive findings are commonly seen in positron emission tomography computed tomography imaging. One of the most common false positive finding is uptake of fluorodeoxyglucose in brown adipose tissue. Herein, we report two cases with incidentally detected hibernomas-a brown fat containing tumor with metabolic activity