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Sample records for 64-slice multi-slice computed

  1. Comparison of myocardial perfusion SPECT with 64-slice multi-slice computed tomography angiography in cardiac screening of asymptomatic diabetic patients

    Lim, Il Han; Lee, Won Woo; Chang, Hyuck Jae; Choi, Sang II; Kim, Sang Eun [Seoul National Univ. College of Medicine, Seoul (Korea, Republic of)

    2007-07-01

    Asymptomatic diabetic patients may suffer silent ischemia. However, the question that what is the optimal screening tool for detection of cardiac disease in asymptomatic diabetic patients has not been addressed. We prospectively recruited diabetic patients who had not complained chest pain, and obtained myocardial perfusion SPECT (MPS) and cardiac CT angiography (CTA). We compared perfusion status on MPS with findings on CTA. A total of 110 diabetic patients (Age range 41-84, mean age 61.6{+-}7.74; gender, M: F 66:44) without cardiac symptom underwent both MPS and CTA. The MPS protocol was one-day single isotope study, adenosine stress Tc-99m MIBI/rest Tc-99m MIBI. CTA was conducted using 64-slice multi-slice CT (Brillance64, Philips Medical Systems). Perfusion status on MPS was assessed by summed-stress score (SSS) using 20-segment model, and SSS of {>=}4 was considered abnormal. Coronary stenosis of more than 50% luminal narrowing in CTA was considered significant, and coronary artery calcium scoring (CACS) was graded as: < or =10, 11-100, 101-400, or >400. MPS found abnormal perfusion in 11.8% (13/110) and CTA significant coronary stenosis in 20.9% (23/110). Five patients showed both abnormal perfusion and significant coronary stenosis. CACS (n=103 patients) were measured as; < or =10 in 45.6%, 11-100 in 28.1%, 101-400 in 19.4%, and >400 in 6.8%. The patient proportion of abnormal MPS in each CACS group were; 10.6% with < or = 10, 17.2% with 11-100, 5% with 101-400, and 0% with >400. The patient proportion of significant coronary stenosis on CTA in each CACS group were; 2.13% with < or =10, 27.6% with 11-100, 35% with 101-400, and 57.1% with >400. In asymptomatic diabetic patients, coronary stenosis by CTA showed correlation with coronary artery calcium scoring, but myocardial perfusion status by MPS did not. Long-term evaluation is essential for determination of prognostic significance of MPS and cardiac CTA.

  2. 64-slice Computed Tomography Assessment of Coronary Artery Stents: a Phantom Study

    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.

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

    "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

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

    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)

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

    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...

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

    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.)

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

    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.

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

    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

  9. Quantitative parameters of image quality in 64-slice computed tomography angiography of the coronary arteries

    We explored quantitative parameters of image quality in consecutive patients undergoing 64-slice multi-detector computed tomography (MDCT) coronary angiography for clinical reasons. Forty-two patients (36 men, mean age 61 ± 11 years, mean heart rate 63 ± 10 bpm) underwent contrast-enhanced MDCT coronary angiography with a 64-slice scanner (Siemens Sensation 64, 64 mmx 0.6 mm collimation, 330 ms tube rotation, 850 mAs, 120 kV). Two independent observers measured the overall visualized vessel length and the length of the coronary arteries visualized without motion artifacts in curved multiplanar reformatted images. Contrast-to-noise ratio was measured in the proximal and distal segments of the coronary arteries. The mean length of visualized coronary arteries was: left main 12 ± 6 mm, left anterior descending 149 ± 25 mm, left circumflex 89 ± 30 mm, and right coronary artery 161 ± 38 mm. On average, 97 ± 5% of the total visualized vessel length was depicted without motion artifacts (left main 100 ± 0%, left anterior descending 97 ± 6%, left circumflex 98 ± 5%, and right coronary artery 95 ± 6%). In 27 patients with a heart rate ≤65 bpm, 98 ± 4% of the overall visualized vessel length was imaged without motion artifacts, whereas 96 ± 6% of the overall visualized vessel length was imaged without motion artifacts in 15 patients with a heart rate >65 bpm (p < 0.001). The mean contrast-to-noise ratio in all measured coronary arteries was 14.6 ± 4.7 (proximal coronary segments: range 15.1 ± 4.4 to 16.1 ± 5.0, distal coronary segments: range 11.4 ± 4.2 to 15.9 ± 4.9). In conclusion, 64-slice MDCT permits reliable visualization of the coronary arteries with minimal motion artifacts and high CNR in consecutive patients referred for non-invasive MDCT coronary angiography. Low heart rate is an important prerequisite for excellent image quality

  10. Virtual colonoscopy with multi-slice computed tomography

    Subject: Using multi-slice computed tomography (MSCT) large body areas can scanned with high spatial resolution. In this study, MSCT was employed for virtual colonoscopy in various pathologies of the colon. Results: Nine polyps and four of five colon carcinomas were detected using MSCT virtual colonoscopy. In three patients with ulcerative colitis virtual coloscopy revealed morphological alterations compatible with this disease. In two of four patients with multiple diverticula of the colon the true extent of the disorder could be assessed in virtual colonoscopy. (orig.)

  11. Quantitative parameters to compare image quality of non-invasive coronary angiography with 16-slice, 64-slice and dual-source computed tomography.

    Burgstahler, Christof; Reimann, Anja; Brodoefel, Harald; Daferner, Ulrike; Herberts, Tina; Tsiflikas, Ilias; Thomas, Christoph; Drosch, Tanja; Schroeder, Stephen; Heuschmid, Martin

    2009-03-01

    Multi-slice computed tomography (MSCT) is a non-invasive modality to visualize coronary arteries with an overall good image quality. Improved spatial and temporal resolution of 64-slice and dual-source computed tomography (DSCT) scanners are supposed to have a positive impact on diagnostic accuracy and image quality. However, quantitative parameters to compare image quality of 16-slice, 64-slice MSCT and DSCT are missing. A total of 256 CT examinations were evaluated (Siemens, Sensation 16: n = 90; Siemens Sensation 64: n = 91; Siemens Definition: n = 75). Mean Hounsfield units (HU) were measured in the cavum of the left ventricle (LV), the ascending aorta (Ao), the left ventricular myocardium (My) and the proximal part of the left main (LM), the left anterior descending artery (LAD), the right coronary artery (RCA) and the circumflex artery (CX). Moreover, the ratio of intraluminal attenuation (HU) to myocardial attenuation was assessed for all coronary arteries. Clinical data [body mass index (BMI), gender, heart rate] were accessible for all patients. Mean attenuation (CA) of the coronary arteries was significantly higher for DSCT in comparison to 64- and 16-slice MSCT within the RCA [347 +/- 13 vs. 254 +/- 14 (64-MSCT) vs. 233 +/- 11 (16-MSCT) HU], LM (362 +/- 11/275 +/- 12/262 +/- 9), LAD (332 +/- 17/248 +/- 19/219 +/- 14) and LCX (310 +/- 12/210 +/- 13/221 +/- 10, all p < 0.05), whereas there was no significant difference between DSCT and 64-MSCT for the LV, the Ao and My. Heart rate had a significant impact on CA ratio in 16-slice and 64-slice CT only (p < 0.05). BMI had no impact on the CA ratio in DSCT only (p < 0.001). Improved spatial and temporal resolution of dual-source CT is associated with better opacification of the coronary arteries and a better contrast with the myocardium, which is independent of heart rate. In comparison to MSCT, opacification of the coronary arteries at DSCT is not affected by BMI. The main advantage of DSCT lies with the

  12. Quantitative parameters to compare image quality of non-invasive coronary angiography with 16-slice, 64-slice and dual-source computed tomography

    Burgstahler, Christof [University Hospital Tuebingen, Department of Cardiology, Tuebingen (Germany)]|[Eberhard-Karls-University Tuebingen, Department of Internal Medicine III-Cardiology, Tuebingen (Germany); Reimann, Anja; Brodoefel, Harald; Tsiflikas, Ilias; Thomas, Christoph; Heuschmid, Martin [University Hospital Tuebingen, Department of Diagnostic Radiology, Tuebingen (Germany); Daferner, Ulrike; Drosch, Tanja; Schroeder, Stephen [University Hospital Tuebingen, Department of Cardiology, Tuebingen (Germany); Herberts, Tina [University of Tuebingen, Department of Medical Biometry, Tuebingen (Germany)

    2009-03-15

    Multi-slice computed tomography (MSCT) is a non-invasive modality to visualize coronary arteries with an overall good image quality. Improved spatial and temporal resolution of 64-slice and dual-source computed tomography (DSCT) scanners are supposed to have a positive impact on diagnostic accuracy and image quality. However, quantitative parameters to compare image quality of 16-slice, 64-slice MSCT and DSCT are missing. A total of 256 CT examinations were evaluated (Siemens, Sensation 16: n=90; Siemens Sensation 64: n=91; Siemens Definition: n=75). Mean Hounsfield units (HU) were measured in the cavum of the left ventricle (LV), the ascending aorta (Ao), the left ventricular myocardium (My) and the proximal part of the left main (LM), the left anterior descending artery (LAD), the right coronary artery (RCA) and the circumflex artery (CX). Moreover, the ratio of intraluminal attenuation (HU) to myocardial attenuation was assessed for all coronary arteries. Clinical data [body mass index (BMI), gender, heart rate] were accessible for all patients. Mean attenuation (CA) of the coronary arteries was significantly higher for DSCT in comparison to 64- and 16-slice MSCT within the RCA [347{+-}13 vs. 254{+-}14 (64-MSCT) vs. 233{+-}11 (16-MSCT) HU], LM (362{+-}11/275 {+-} 12/262{+-}9), LAD (332{+-}17/248{+-}19/219{+-}14) and LCX (310{+-}12/210{+-}13/221{+-}10, all p<0.05), whereas there was no significant difference between DSCT and 64-MSCT for the LV, the Ao and My. Heart rate had a significant impact on CA ratio in 16-slice and 64-slice CT only (p<0.05). BMI had no impact on the CA ratio in DSCT only (p<0.001). Improved spatial and temporal resolution of dual-source CT is associated with better opacification of the coronary arteries and a better contrast with the myocardium, which is independent of heart rate. In comparison to MSCT, opacification of the coronary arteries at DSCT is not affected by BMI. The main advantage of DSCT lies with the heart rate independency

  13. Quantitative parameters to compare image quality of non-invasive coronary angiography with 16-slice, 64-slice and dual-source computed tomography

    Multi-slice computed tomography (MSCT) is a non-invasive modality to visualize coronary arteries with an overall good image quality. Improved spatial and temporal resolution of 64-slice and dual-source computed tomography (DSCT) scanners are supposed to have a positive impact on diagnostic accuracy and image quality. However, quantitative parameters to compare image quality of 16-slice, 64-slice MSCT and DSCT are missing. A total of 256 CT examinations were evaluated (Siemens, Sensation 16: n=90; Siemens Sensation 64: n=91; Siemens Definition: n=75). Mean Hounsfield units (HU) were measured in the cavum of the left ventricle (LV), the ascending aorta (Ao), the left ventricular myocardium (My) and the proximal part of the left main (LM), the left anterior descending artery (LAD), the right coronary artery (RCA) and the circumflex artery (CX). Moreover, the ratio of intraluminal attenuation (HU) to myocardial attenuation was assessed for all coronary arteries. Clinical data [body mass index (BMI), gender, heart rate] were accessible for all patients. Mean attenuation (CA) of the coronary arteries was significantly higher for DSCT in comparison to 64- and 16-slice MSCT within the RCA [347±13 vs. 254±14 (64-MSCT) vs. 233±11 (16-MSCT) HU], LM (362±11/275 ± 12/262±9), LAD (332±17/248±19/219±14) and LCX (310±12/210±13/221±10, all p<0.05), whereas there was no significant difference between DSCT and 64-MSCT for the LV, the Ao and My. Heart rate had a significant impact on CA ratio in 16-slice and 64-slice CT only (p<0.05). BMI had no impact on the CA ratio in DSCT only (p<0.001). Improved spatial and temporal resolution of dual-source CT is associated with better opacification of the coronary arteries and a better contrast with the myocardium, which is independent of heart rate. In comparison to MSCT, opacification of the coronary arteries at DSCT is not affected by BMI. The main advantage of DSCT lies with the heart rate independency, which might have a

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

    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.

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

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

    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.

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

    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.

  17. Detection of pulmonary embolism using 64-slice multidetector-row computed tomography: accuracy and reproducibility on different image reconstruction parameters

    Jung, Jung Im; Ahn, Myeong Im; Park, Seog Hee (Dept. of Radiology, Seoul St Mary' s Hospital, College of Medicine, The Catholic Univ. of Korea (Korea, Republic of)), email: jijung@catholic.ac.kr; Kim, Ki Jun (Deparment of Radiology, Incheon St Mary' s Hospital, College of Medicine, The Catholic Univ. of Korea (Korea, Republic of)); Kim, Hyo Rim (Deparment of Radiology, Yeouido St Mary' s Hospital, College of Medicine, The Catholic Univ. of Korea (Korea, Republic of)); Park, Hyun Jin (Dept. of Radiology, St Vincent Hospital, College of Medicine, The Catholic Univ. of Korea (Korea, Republic of)); Jung, SeungHee; Lim, Hyeon Woo (Deparment of Preventive Medicine, College of Medicine, The Catholic Univ. of Korea (Korea, Republic of))

    2011-05-15

    Background Direct comparison of different image reconstruction parameters to detect pulmonary embolism (PE) using 64-slice multidetector-row computed tomography (MDCT) is absent and the most accurate image reconstruction parameters have not yet been proven. Purpose To compare different image reconstruction parameters for detecting PE using 64-slice MDCT in patients suspected of having an acute PE. Material and Methods Forty patients who underwent pulmonary CT angiography with 64-slice MDCT for a suspected PE were included. Different image reconstruction parameters were used for each patient: axial and coronal images with slice thicknesses of 0.625 mm, 1.3 mm, and 2.5 mm and axial maximum intensity projection (MIP) images with slab thicknesses of 1.3 mm, 2.5 mm, and 5 mm. Four experienced radiologists reviewed the images. The diagnosis of a PE was based on consensus review of axial 0.625 mm slice thickness images by two chest radiologists with allowing multiplanar reconstruction. Accuracy and reproducibility (kappa value) were evaluated. Results In 15 of 40 patients, a PE was diagnosed. For detecting lobar PEs, axial images with a slice thickness of 1.25 mm and all coronal re-formatted images showed comparable results to axial images with a slice thickness of 0.625 mm. For detecting segmental PEs, axial images with a slice thickness of 1.25 mm and coronal images with a slice thickness of 0.625 mm re-formatted images showed comparable results to axial images of a slice thickness of 0.625 mm. For detecting subsegmental PEs, axial images with a slice thickness of 0.625 mm showed the highest sensitivity. Better reproducibility was obtained when the thinner slice thickness reconstructions were in axial and coronal images. However, reproducibility of MIP images with slab thicknesses of 2.5 mm and 5 mm was similar for detecting segmental and subsegmental PEs. Conclusion Thin-slice reconstruction of less than 1 mm is mandatory for visualization of PE at the subsegmental

  18. 64 slice-coronary computed tomography sensitivity and specificity in the evaluation of coronary artery bypass graft stenosis: A meta-analysis.

    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

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

    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

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

    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...

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

    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

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

    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...

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

    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.

  5. Comparison of 64-slice computed tomography angiography and coronary angiography for the detection and assessment of coronary artery disease in patients with angina: A systematic review

    Background: Coronary artery disease (CAD) is the leading cause of death in Western countries. It presents itself in various ways, the commonest being angina. According to the Royal College of Radiologist referral guidelines, Coronary Angiography (CA) is currently the gold standard for diagnosis and evaluation of CAD. However, due to the invasive nature and expense of CA there is a perceived need for a primary non-invasive imaging modality to supersede it. Computed tomography angiography (CTA), utilising 64-slice technology, may be a less invasive alternative to CA. Aim: To consider the research evidence for the current gold standard diagnostic test for CAD. Specifically, which is more sensitive and specific for detecting CAD in patients with angina; 64-slice CTA or CA? Inclusion Criteria: Prospective, non-randomised control trials and diagnostic accuracy studies comparing 64-slice CTA and CA were included. Participants were adults with angina with suspected or known CAD. Method: An electronic search of the databases; AMED, CINAHL, Cochrane Library, EMBASE, MEDLINE and Science Direct, was conducted between January 2004 and April 2012. Secondary hand-searching of grey literature was undertaken. Two reviewers independently determined studies for inclusion, assessed quality, using SIGN50, and extracted data. Diagnostic value of 64-slice CTA and CA was compared and analysed at patient and segment level. Results: Ten studies were included in the critical review enrolling 1188 patients. At patient level sensitivity for 64-slice CTA ranged from 88% to 100%, specificity 64–92%, PPV 86–97% and NPV 76.9–100%. At segment level sensitivity for 64-slice CTA ranged from 73% to 100%, specificity 83–98%, PPV 47–90% and NPV 89–100% Conclusion: At both patient and segment level, 64-slice CTA is a highly sensitive and specific non-invasive alternative to CA for diagnosis of significant stenosis in patients with angina. For standalone diagnosis of CAD current research would

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

    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

  7. Evaluation of intestinal tuberculosis by multi-slice computed tomography enterography

    Zhao, Jing; Cui, Min-Yi; Chan, Tao; Mao, Ren; Luo, Yanji; Barua, Indira; Chen, Minhu; Li, Zi-Ping; Feng, Shi-Ting

    2015-01-01

    Background Multi-slice computed tomography enterography (MSCTE) is now widely used to diagnose and monitor intestinal disease. Preliminary studies suggest that MSCTE may be useful in detecting intestinal tuberculosis (ITB). We sought to assess the use of MSCTE for the diagnosis of ITB in our medical center. Methods In this retrospective study, 15 patients (11 males and 4 females, 6 to 65 years old) were enrolled and diagnosed with ITB by MSCTE. Diagnosis were confirmed by pathology or clinica...

  8. Comparison of 64-slice multi-detector computed tomography coronary angiography between asymptomatic, type 2 diabetes mellitus and impaired glucose tolerance patients

    Cardiovascular disease is the most frequent cause of death and disability for diabetic patients, and patients with diabetes are more likely to have silent ischemia. Multi-detector computed tomography (MDCT) allows non-invasive assessment of coronary artery stenosis and plaque properties. In this study, we investigated whether 64-slice MDCT can non-invasively identify significant coronary artery stenosis in asymptomatic, type 2 diabetes mellitus (T2DM) and impaired glucose tolerance (IGT) patients. The study population consisted of 154 consecutive asymptomatic patients [IGT (n=93), T2DM (n=61)]. All patients underwent contrast-enhanced 64-slice MDCT. The number of diseased coronary segments was classified as showing obstructive (≥50% luminal narrowing) disease or not. Significant coronary stenosis was detected in 43 (27.9%) of 154 enrolled patients. Patients with T2DM showed significantly more coronary stenosis than patients with IGT (41% vs. 19.4%; p<0.01). Twenty-three patients [14.9%; IGT (n=9), T2DM (n=14)] underwent percutaneous coronary intervention (PCI) for severe stenosis. Patients with T2DM showed significantly more calcified plaque than IGT (47.5% vs. 29%; p<0.05), but not significantly more soft plaque (19.7% vs. 15.1%; ns), or significantly different remodeling index (1.05±0.18 vs. 1.04±0.21; ns), respectively. 64-Slice MDCT can non-invasively identify significant coronary artery stenosis in asymptomatic, T2DM and IGT patients. (author)

  9. The value of multi-slice computed tomography for early diagnosis of focal cerebral ischemia

    The aim of this survey is the characterization of the present value of multi-slice computed tomography (MSCT) for the assessment of hyperacute cerebral ischemia based on our experience and a review of the literature. MSCT is compared with single-slice CT (SSCT) as to the diagnostic value of standard cranial CT, CT angiography (CTA) and perfusion CT. CTA obtained with MSCT surpasses CTA obtained with SSCT. For perfusion CT, the value added by MSCT is small. With regard to standard cranial CT, MSCT and SSCT are considered equivalent. CTA and perfusion CT should be used in patients with acute stroke if the indication for thrombolysis is entertained but diffusion and perfusion weighted MRI cannot be carried out. This applies to both SSCT and MSCT. If advanced MRI and advanced CT are available, MRI continues to be the preferred imaging modality. (orig.)

  10. A method of predicting the image noise in paediatric multi-slice computed tomography images

    The purpose of this study was to develop an equation with which to determine the tube current to be used in order to obtain a certain image noise level for differently sized children undergoing multi-slice computed tomography examination. The relationship between image noise and detector dose for different examination protocols was established for a LightSpeed Ultra, an eight slice CT from GEMS, using homogeneous water phantoms of different sizes. Three different anatomical areas (head, thorax and abdomen) were studied in 111 patients between 0 and 17 y of age. The mean ratio between the calculated and the measured noise in patient images was established for the different areas. Head examinations showed the best correlation (measured-to-calculated noise ratio = 1.01). In the thorax, the calculated noise was generally higher than the measured noise (ratio = 0.74), and in the abdomen, the opposite result was found (ratio = 1.20). (authors)

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

    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).

  12. Cardiac sarcoidosis evaluated with gadolinium-enhanced magnetic resonance and contrast-enhanced 64-slice computed tomography.

    Smedema, Jan-Peter; Truter, Rene; de Klerk, Petra A; Zaaiman, Leonie; White, Leonie; Doubell, Anton F

    2006-09-20

    Sarcoidosis is a multi-system granulomatous disorder of unknown etiology with symptomatic cardiac involvement in up to 7% of patients. The clinical features of sarcoid heart disease include congestive heart failure, arrhythmias, conduction disturbances, and sudden death. We evaluated the value of contrast-enhanced multi-detector computed tomography in delineating myocardial scar and granulomatous inflammation by comparing our findings with gadolinium magnetic resonance in a patient diagnosed with cardiac sarcoidosis. PMID:16257460

  13. Establishment of multi-slice computed tomography (MSCT) reference level in Johor, Malaysia

    Karim, M. K. A.; Hashim, S.; Bakar, K. A.; Muhammad, H.; Sabarudin, A.; Ang, W. C.; Bahruddin, N. A.

    2016-03-01

    Radiation doses from computed tomography (CT) are the highest and most hazardous compared to other imaging modalities. This study aimed to evaluate radiation dose in Johor, Malaysia to patients during computed tomography examinations of the brain, chest and abdomen and to establish the local diagnostic reference levels (DRLs) as are present with the current, state- of-art, multi-slice CT scanners. Survey forms were sent to five centres performing CT to obtain data regarding acquisition parameters as well as the dose information from CT consoles. CT- EXPO (Version 2.3.1, Germany) was used to validate the dose information. The proposed DRLs were indicated by rounding the third quartiles of whole dose distributions where mean values of CTDIw (mGy), CTDIvol (mGy) and DLP (mGy.cm) were comparable with other reference levels; 63, 63, and 1015 respectively for CT Brain; 15, 14, and 450 respectively for CT thorax and 16, 17, and 590 respectively for CT abdomen. The study revealed that the CT practice and dose output were revolutionised, and must keep up with the pace of introductory technology. We suggest that CTDIvol should be included in current national DRLs, as modern CTs are configured with a higher number of detectors and are independent of pitch factors.

  14. Volumetric analysis of coronary plaque characterization in patients with metabolic syndrome using 64-slice multi-detector computed tomography

    Metabolic syndrome (MetS) is associated with adverse cardiovascular events and mortality, where acute coronary syndrome significantly impacts on mortality and morbidity. In contrast, evidences have accumulated that the lipid-rich plaque might play a critical role in acute coronary syndrome. The study population consisted of 94 patients with suspected angina pectoris who underwent multi-detector computed tomography (MDCT). Of those, we identified 41 with MetS. In MDCT analysis, low-density plaque volume (LDPV) (42±28 vs 24±18 mm3, P=0.0003), moderate-density plaque volume (105±41 vs 82±33 mm(3), P=0.003), total plaque volume (164±70 vs 118±59 mm3), P=0.0008) and %LDPV (24.2±10.0 vs 18.3±7.1%, P=0.01) were significantly increased in the MetS group compared to the non-MetS group. Multivariate linear regression analysis after adjusting for confounding variables revealed that MetS was significantly correlated with an increase in %LDPV (β=0.48, P=0.0001). Multivariate logistic regression analysis for lipid-rich plaque after adjusting for confounding variables indicated that MetS was significantly associated with lipid-rich plaque (odds ratio: 5.99, 95% confidence intervals: 1.94-18.6, P=0.002). Patients with MetS were strongly related to having a lipid-rich composition in their coronary plaque, as detected by MDCT. (author)

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

    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)

  16. 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

    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.)

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

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

    2011-11-15

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

  18. Virtual colonoscopy with multi-slice computed tomography; Virtuelle Koloskopie mit der Mehrschichtcomputertomographie. Vorlaeufige Ergebnisse

    Rust, G.-F.; Eisele, O.; Reiser, M. [Institut fuer Klinische Radiologie, Klinikum Grosshadern, Muenchen Univ. (Germany); Hoffmann, J.N.; Kopp, R.; Fuerst, H. [Chirurgische Klinik und Poliklinik, Klinikum der Univ. Muenchen (Germany)

    2000-03-01

    Subject: Using multi-slice computed tomography (MSCT) large body areas can scanned with high spatial resolution. In this study, MSCT was employed for virtual colonoscopy in various pathologies of the colon. Results: Nine polyps and four of five colon carcinomas were detected using MSCT virtual colonoscopy. In three patients with ulcerative colitis virtual coloscopy revealed morphological alterations compatible with this disease. In two of four patients with multiple diverticula of the colon the true extent of the disorder could be assessed in virtual colonoscopy. (orig.) [German] Fragestellung: Die Mehrschichtcomputertomographie (MSCT) vermag, grosse Organbereiche mit hoher raeumlicher Aufloesung zu untersuchen. Daher koennen auch fuer die virtuelle Koloskopie eine bisher nicht erreichbare Ortsaufloesung und Detailtreue erwartet werden. Die ersten Ergebnisse mit der MSCT-Koloskopie bei unterschiedlichen pathologischen Veraenderungen des Kolons werden vorgestellt. Ergebnisse: 4 von 5 Kolonkarzinomen konnten mit der virtuellen Koloskopie dargestellt werden. Bei 3 Patienten wurden mit der virtuellen Koloskopie typische Veraenderungen der Colitis ulcerosa dargestellt, wovon ein Patient die konventionelle Koloskopie nicht tolerierte. Bei 9 Patienten mit Kolonpolypen stimmten die virtuelle und konventionelle Koloksopie vollstaendig ueberein. Bei 4 Patienten mit Divertikulose war mit der virtuellen Koloskopie nur in 2 Faellen der Befund vollstaendig zu sichern. (orig.)

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

    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 ...

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

    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 ...

  1. A comparative evaluation of Cone Beam Computed Tomography (CBCT) and Multi-Slice CT (MSCT)

    Aims: To compare image quality and visibility of anatomical structures in the mandible between five Cone Beam Computed Tomography (CBCT) scanners and one Multi-Slice CT (MSCT) system. Materials and methods: One dry mandible was scanned with five CBCT scanners (Accuitomo 3D, i-CAT, NewTom 3G, Galileos, Scanora 3D) and one MSCT system (Somatom Sensation 16) using 13 different scan protocols. Visibility of 11 anatomical structures and overall image noise were compared between CBCT and MSCT. Five independent observers reviewed the CBCT and the MSCT images in the three orthographic planes (axial, sagittal and coronal) and assessed image quality on a five-point scale. Results: Significant differences were found in the visibility of the different anatomical structures and image noise level between MSCT and CBCT and among the five CBCT systems (p = 0.0001). Delicate structures such as trabecular bone and periodontal ligament were significantly less visible and more variable among the systems in comparison with other anatomical structures (p = 0.0001). Visibility of relatively large structures such as mandibular canal and mental foramen was satisfactory for all devices. The Accuitomo system was superior to MSCT and all other CBCT systems in depicting anatomical structures while MSCT was superior to all other CBCT systems in terms of reduced image noise. Conclusions: CBCT image quality is comparable or even superior to MSCT even though some variability exists among the different CBCT systems in depicting delicate structures. Considering the low radiation dose and high-resolution imaging, CBCT could be beneficial for dentomaxillofacial radiology.

  2. A comparative evaluation of Cone Beam Computed Tomography (CBCT) and Multi-Slice CT (MSCT)

    Liang Xin, E-mail: Xin.Liang@med.kuleuven.b [Oral Imaging Centre, School of Dentistry, Oral Pathology and Maxillofacial Surgery, Faculty of Medicine, Catholic University of Leuven (Belgium); College of Stomatology, Dalian Medical University (China); Jacobs, Reinhilde, E-mail: Reinhilde.Jacobs@uz.kuleuven.b [Oral Imaging Centre, School of Dentistry, Oral Pathology and Maxillofacial Surgery, Faculty of Medicine, Catholic University of Leuven (Belgium); Hassan, Bassam, E-mail: b.hassan@acta.n [Department of Oral Radiology, Academic Centre for Dentistry Amsterdam (ACTA), Amsterdam (Netherlands); Li Limin, E-mail: Limin.Li@uz.kuleuven.b [Department of Paediatric Dentistry and Special Dental Care, School of Dentistry, Oral Pathology and Maxillofacial Surgery, Faculty of Medicine, Catholic University of Leuven (Belgium); Pauwels, Ruben, E-mail: Ruben.Pauwels@med.kuleuven.b [Oral Imaging Centre, School of Dentistry, Oral Pathology and Maxillofacial Surgery, Faculty of Medicine, Catholic University of Leuven (Belgium); Corpas, Livia, E-mail: LiviaCorpas@gmail.co [Oral Imaging Centre, School of Dentistry, Oral Pathology and Maxillofacial Surgery, Faculty of Medicine, Catholic University of Leuven (Belgium); Souza, Paulo Couto, E-mail: Paulo.CoutoSouza@med.kuleuven.b [Oral Imaging Centre, School of Dentistry, Oral Pathology and Maxillofacial Surgery, Faculty of Medicine, Catholic University of Leuven (Belgium); Martens, Wendy, E-mail: wendy.martens@uhasselt.b [Department of Basic Medical Sciences, Faculty of Medicine, University of Hasselt, Diepenbeek (Belgium); Shahbazian, Maryam, E-mail: Maryam.Shahbazian@student.kuleuven.b [Oral Imaging Centre, School of Dentistry, Oral Pathology and Maxillofacial Surgery, Faculty of Medicine, Catholic University of Leuven (Belgium); Alonso, Arie, E-mail: ariel.alonso@uhasselt.b [Department of Biostatistics and Statistical Bioinformatics, Universiteit Hasselt (Belgium)

    2010-08-15

    Aims: To compare image quality and visibility of anatomical structures in the mandible between five Cone Beam Computed Tomography (CBCT) scanners and one Multi-Slice CT (MSCT) system. Materials and methods: One dry mandible was scanned with five CBCT scanners (Accuitomo 3D, i-CAT, NewTom 3G, Galileos, Scanora 3D) and one MSCT system (Somatom Sensation 16) using 13 different scan protocols. Visibility of 11 anatomical structures and overall image noise were compared between CBCT and MSCT. Five independent observers reviewed the CBCT and the MSCT images in the three orthographic planes (axial, sagittal and coronal) and assessed image quality on a five-point scale. Results: Significant differences were found in the visibility of the different anatomical structures and image noise level between MSCT and CBCT and among the five CBCT systems (p = 0.0001). Delicate structures such as trabecular bone and periodontal ligament were significantly less visible and more variable among the systems in comparison with other anatomical structures (p = 0.0001). Visibility of relatively large structures such as mandibular canal and mental foramen was satisfactory for all devices. The Accuitomo system was superior to MSCT and all other CBCT systems in depicting anatomical structures while MSCT was superior to all other CBCT systems in terms of reduced image noise. Conclusions: CBCT image quality is comparable or even superior to MSCT even though some variability exists among the different CBCT systems in depicting delicate structures. Considering the low radiation dose and high-resolution imaging, CBCT could be beneficial for dentomaxillofacial radiology.

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

    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 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.

  4. Multi-slice computed tomography assessment of bronchial compression with absent pulmonary valve

    Zhong, Yu-Min; Sun, Ai-Min; Wang, Qian; Zhu, Ming; Qiu, Hai-Sheng [Shanghai Children' s Medical Center and Shanghai Jiao Tong University Medical School, Department of Radiology, Shanghai (China); Jaffe, Richard B. [Primary Children' s Medical Center, Department of Medical Imaging, Salt Lake City, UT (United States); Liu, Jin-Fen [Shanghai Children' s Medical Center, Department of Cardiothoracic Surgery, Shanghai (China); Gao, Wei [Shanghai Children' s Medical Center and Shanghai Jiao Tong University Medical School, Department of Cardiology, Shanghai (China); Berdon, Walter E. [Children' s Hospital of New York, Department of Radiology, New York, NY (United States)

    2014-07-15

    Absent pulmonary valve is a rare cardiovascular anomaly that can result in profound tracheobronchial compression. To demonstrate the advantage of multi-slice CT in diagnosing tracheobronchial compression, its severity as related to the adjacent dilated pulmonary arteries, and associated lung and cardiac lesions. We included children with absent pulmonary valve who were reviewed by multi-slice CT during a 17-year period. The number and locations of stenoses and lung lesions were noted and the severity of stenosis was categorized. The diameter of the pulmonary artery was measured and associated cardiac defects were demonstrated. Thirty-one children (14 girls and 17 boys) were included. Of these, 29 had ventricular septal defect and 2 had an intact ventricular septum. Twenty-nine children (94%) had tracheobronchial compression, judged to be mild in nine children (31%), moderate in 10 (34%) and severe in 10 (34%). The different locations of the stenosis (carina, main bronchi, lobar and segmental bronchi) were observed. And the number and location of lung lesions demonstrated that the right middle and left upper and lower lobes were often affected. The diameter of the pulmonary artery in these children was well above normal published values, and Spearman rank correlation analysis showed a correlation between the size of the pulmonary artery and the severity of the tracheobronchial stenosis. Nineteen children (61%) underwent surgery and 4 of these children had a multi-slice CT post-operative follow-up study. Absent pulmonary valve can cause significant morbidity and mortality in children. Multi-slice CT can accurately depict areas of tracheobronchial compression, associated lung lesions and cardiac defects, helping to direct the surgeon. (orig.)

  5. Multi-slice computed tomography assessment of bronchial compression with absent pulmonary valve

    Absent pulmonary valve is a rare cardiovascular anomaly that can result in profound tracheobronchial compression. To demonstrate the advantage of multi-slice CT in diagnosing tracheobronchial compression, its severity as related to the adjacent dilated pulmonary arteries, and associated lung and cardiac lesions. We included children with absent pulmonary valve who were reviewed by multi-slice CT during a 17-year period. The number and locations of stenoses and lung lesions were noted and the severity of stenosis was categorized. The diameter of the pulmonary artery was measured and associated cardiac defects were demonstrated. Thirty-one children (14 girls and 17 boys) were included. Of these, 29 had ventricular septal defect and 2 had an intact ventricular septum. Twenty-nine children (94%) had tracheobronchial compression, judged to be mild in nine children (31%), moderate in 10 (34%) and severe in 10 (34%). The different locations of the stenosis (carina, main bronchi, lobar and segmental bronchi) were observed. And the number and location of lung lesions demonstrated that the right middle and left upper and lower lobes were often affected. The diameter of the pulmonary artery in these children was well above normal published values, and Spearman rank correlation analysis showed a correlation between the size of the pulmonary artery and the severity of the tracheobronchial stenosis. Nineteen children (61%) underwent surgery and 4 of these children had a multi-slice CT post-operative follow-up study. Absent pulmonary valve can cause significant morbidity and mortality in children. Multi-slice CT can accurately depict areas of tracheobronchial compression, associated lung lesions and cardiac defects, helping to direct the surgeon. (orig.)

  6. Multi-slice computed tomography for diagnosis of combined thoracoabdominal injury

    Jun Liu; Weidong Yue; Dingyuan Du

    2015-01-01

    Purpose:To investigate the diagnostic value of multi-slice computed tomography (MSCT) for combined thoracoabdominal injury.Methods:A retrospective study was conducted to analyze the clinical data and MSCT images of 68 patients who sustained a combined thoracoabdominal injury associated with diaphragm rupture,and 18 patients without diaphragm rupture.All the patients were admitted and treated in the Chongqing Emergency Medical Center (a level Ⅰ trauma center) between July 2005 and February 2014.There were 71 males and 15 females with a mean age of 39.1 years (range 13-88 years).Among the 86 patients,40 patients suffered a penetrating injury,46 suffered a blunt injury as a result of road traffic accident in 21 cases,fall from a height in 16,and crushing injury in 9.The Mscr images were retrospectively reviewed by two radiologists.The results of CT diagnosis were compared with surgical findings and/or follow-up results.Results:Among the 86 cases,diaphragm discontinuity was found in 29 cases,segmental nonrecognition of the diaphragm in 14,diaphragmatic hernia in 21,collar sign in 14,dependent viscera sign in 18,elevated abdominal organs in 21,bowel wall thickening and/or hematoma in 6,and pneumoperitoneum in 8.CT diagnostic accuracy for diaphragm rupture was 88.4% in the right side and 90.7% in the left side.cT diagnostic accuracy for hemopneumothorax,pulmonary contusion,mediastinal hemorrhage,kidney and adrenal gland injuries was 100%,while for liver,spleen and pancreas injuries was 96.5%,96.5%,94.2% respectively.Conclusion:To reach an early diagnosis of combined thoracoabdominal injury,surgeons and radiologists should be familiar with all kinds of images which might show signs of diaphragm rupture,such as diaphragm discontinuity,segmental nonrecognition of the diaphragm,dangling diaphragm sign,diaphragm herniation,collar sign,dependent viscera sign,and elevated abdominal organs.

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

    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.

  8. Assessment of left atrial volume and function: a comparative study between echocardiography, magnetic resonance imaging and multi slice computed tomography

    Kühl, J Tobias; Lønborg, Jacob; Fuchs, Andreas;

    2012-01-01

    dynamic LA volume changes. Conversely, cardiac magnetic resonance imaging (CMR) and multi-slice computed tomography (MSCT) appears more appropriate for such measures. We sought to determine the relationship between LA size assessed with TTE and LA size and function assessed with CMR and MSCT. Fifty......Measurement of left atrial (LA) maximal volume (LA(max)) using two-dimensional transthoracic echocardiography (TTE) provides prognostic information in several cardiac diseases. However, the relationship between LA(max) and LA function is poorly understood and TTE is less well suited for measuring...

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

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

    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.)

  11. Multi-slice Computed Tomography Angiography in the Detection of Residual or Recurrent Cerebral Aneurysms after Surgical Clipping

    Purpose: To assess the diagnostic accuracy of multi-slice computed tomography (MSCT) angiography compared to digital subtraction angiography (DSA) in detecting residual or recurrent aneurysms in patients undergoing aneurysm clipping surgery. Material and Methods: Eight patients with nine aneurysms who had both MSCTA and DSA were included in the study. Two independent experienced neuroradiologists evaluated the examinations. Results: Accuracy, sensitivity, and specificity of detecting residual or recurrent aneurysms on MSCTA were 0.80, 0.60, and 1.00, respectively. Positive and negative predictive values were 1.00 and 0.71, respectively. Conclusion: MSCTA is a promising technique for evaluating residual or recurrent aneurysms in patients undergoing surgical treatment of aneurysm with titanium clips

  12. 心脏二尖瓣病变的多层螺旋CT诊断%Multi-slice Spiral Computed Tomography in the Diagnosis of Mitral Valve Diseases

    吴丽娜; 鹿强

    2016-01-01

    本文从心脏二尖瓣多层螺旋CT研究方法、正常解剖的螺旋CT表现、二尖瓣血流动力特征及心肌改变、二尖瓣膜病螺旋CT表现四个方面分析了心脏二尖瓣病变螺旋CT的诊断价值,并简要介绍了MDCT/EBCT、MRI与US技术在心脏二尖瓣病变诊断方面的优缺点及展望。%This paper analyzed the clinical value of the multi-slice computed tomography in the diagnosis of heart mitral valve diseases in four aspects: the research method of multi-slice CT in heart mitral valve diseases, the manifestations of multi-slice CT in the normal anatomy, the characteristics of hemodynamics and myocardial changes in mitral valve diseases, and the manifestations of multi-slice CT in mitral valve diseases. The paper also brielfy introduced the pros and cons as well as the development prospect of the application of multi-detector computed tomography/electron-beam computed tomography and magnetic resonance imaging and ultrasonography in the diagnosis of mitral valve diseases.

  13. Investigation of an image artefact induced by projection noise inhomogeneity in multi-slice helical computed tomography

    Hsieh, Jiang

    2003-02-01

    The introduction of multi-slice helical computed tomography has fundamentally changed the way radiologists view CT images. Increasing numbers of clinical cases are examined with advanced visualization tools, such as maximum intensity projection, multi-planar reformation and volume rendering. It has been discovered that new image artefacts, which do not appear in the traditional two-dimensional reconstructed images, become visible in images generated by these new tools. In this paper, we investigate the causes of one such artefact, the Venetian blind artefact, which appears as bright-and-dark bands superimposed on three-dimensional images. We demonstrate that such an artefact is caused by the periodical noise variation in the reconstructed images. The image noise variation is, in turn, caused by the interaction of the noise inhomogeneity in the projections with the helical weights. An analytical formula is developed that accurately predicts the presence of such artefacts. Based on our analysis, several approaches are proposed for the artefact reduction or elimination.

  14. Diagnostic accuracy of multi-slice computed tomographic angiography in the detection of cerebral aneurysms

    Multislice computed tomographic angiography is a rapid and minimally invasive method for the detection of intracranial aneurysms. The purpose of this study was to compare Multislice computed tomographic angiography with digital subtraction angiography In the diagnosis of cerebral aneurysms. Patients and Methods: In this cross sectional study we evaluated 111 consecutive patients [42(37.8%) male and 69(62.2%) female], who were admitted under clinical symptoms and signs. suggestive of harboring an intracranial aneurysm by using a four detector Multislice computed tomographic angiography. Then we compared results of Multislice computed tomographic angiography with digital subtraction angiography results as a gold standard method. Digital subtraction angiography was performed by bilateral selective common carotid artery injections and either unilateral or bilateral vertebral artery injections, as necessary. Multislice computed tomographic angiography images were interpreted by one radiologist and digital subtraction angiography was performed by another radiologist who was blinded to the interpretation of the Multislice computed tomographic angiograms. Results: The mean ±S D age of the patients was 49.1±13.6 years (range: 12-84 years). We performed Multislice computed tomographic in 111 and digital subtraction angiography in 85 patients. The sensitivity, specificity, positive predictive value, negative predictive value, positive and negative likelihood ratio of Multislice computed tomographic angiography, when compared with digital subtraction angiography as the gold standard, were 100%, 90%, 87.5%, 100%, 10 and 0, respectively. Conclusion: Multislice computed tomographic angiography seems to be an accurate and noninvasive imaging modality in the diagnosis of intracranial aneurysms

  15. Accuracy and reliability of quantitative measurements in coronary arteries by multi-slice computed tomography: Experimental and initial clinical results

    AIM: To evaluate the accuracy of non-invasive measurements within coronary arteries by multi-slice computed tomography (MSCT). We present experimental as well as clinical data. MATERIALS AND METHODS: Silicon tubes simulating coronary arteries (outer diameter 6 mm, lumen diameter within stenotic area 2 mm) were used for experimental studies. Clinical data were derived from 15 patients in whom vessel diameters were assessed by MSCT, intracoronary ultrasound (ICUS) and quantitative coronary angiography (QCA). MSCT were performed in a Somatom Volume ZoomTMCT system (Siemens, Forchheim, Germany) at 2 collimated slice widths (2.5 mm, 1.0 mm). RESULTS: Outer silicon tube diameters were overestimated by MSCT (6.56 mm ± 0.32 mm). All measurements revealed significantly better results on 1.0 collimation compared to 2.5 mm collimation (outer diameter: 6.36 mm ± 0.22 mm vs 6.76 mm ± 0.27 mm, P < 0.0001; lumen diameters: 1.83 mm ± 0.14 mm vs 1.51 mm ± 0.19 mm,P < 0.0001). The comparison of vessel diameters within human coronary arteries revealed comparable results between ICUS and MSCT (4.89 mm ± 0.67 mm vs 4.91 mm ± 0.71 mm, P = 0.79,r = 0.79, P < 0.0001). QCA-measurements showed significantly lower results (3.67 ± 0.71, P < 0.0001,r = 0.62, P < 0.001). CONCLUSIONS: Experimental as well as initial clinical results indicate acceptable reliability and accuracy of quantitative measurements by MSCT, when using thin collimated slice widths. Partial volume effects lead to a systematic overestimation of vessel size. MSCT has the potential to become an important non-invasive diagnostic tool in patients with coronary artery disease. Schroeder, S. et al. (2001)

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

    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.

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

    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

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

    Yung-Liang Wan

    2010-04-01

    Full Text Available 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 computed tomography for the detectionof anatomical variants in the cardiovascular system is further discussed.

  19. Multi-slice and dual-source CT in cardiac imaging. Principles - protocols - indications - outlook. 2. ed.

    Ohnesorge, B.M. [Siemens Medical Solutions Group China, Beijing (China); Flohr, T.G. [Siemens Medical Solutions, Forchheim (Germany). Div. CT Physics and Applications Development; Becker, C.R.; Reiser, M.F. [Muenchen Univ. Klinikum Grosshadern (Germany). Dept. of Clinical Radiology; Knez, A [Muenchen Univ. Klinikum Grosshadern (Germany). Section Head Imaging

    2007-07-01

    Cardiac diseases, and in particular coronary artery disease, are the leading cause of death and morbidity in industrialized countries. The development of non-invasive imaging techniques for the heart and the coronary arteries has been considered a key element in improving patient care. A breakthrough in cardiac imaging using CT occurred in 1998, with the introduction of multi-slice computed tomography (CT). Since then, amazing advances in performance have taken place with scanners that acquire up to 64 slices per rotation. This book discusses the state-of-the-art developments in multi-slice CT for cardiac imaging as well as those that can be anticipated in the future. It serves as a comprehensive work that covers all aspects of this technology, from the technical fundamentals and image evaluation all the way to clinical indications and protocol recommendations. This fully reworked second edition draws on the most recent clinical experience obtained with 16- and 64-slice CT scanners by world-leading experts from Europe and the United States. It also includes 'hands-on' experience in the form of 10 representative clinical case studies, which are included on the accompanying CD. As a further highlight, the latest results of the very recently introduced dual-source CT, which may soon represent the CT technology of choice for cardiac applications, are presented. This book will not only convince the reader that multi-slice cardiac CT has arrived in clinical practice, it will also make a significant contribution to the education of radiologists, cardiologists, technologists, and physicists-whether newcomers, experienced users, or researchers. (orig.)

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

    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)

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

    施鸿毓; 陈晖; 仇兴标; 曲新凯; 方唯一

    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

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

    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

  3. 64-slice spiral CT in the diagnosis of Caroli disease

    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)

  4. Trabecular bone structure parameters from 3D image processing of clinical multi-slice and cone-beam computed tomography data

    Klintstroem, Eva; Smedby, Oerjan [Linkoeping University, Center for Medical Image Science and Visualization (CMIV), Linkoeping (Sweden); UHL County Council of Oestergoetland, Department of Radiology, Linkoeping (Sweden); Linkoeping University, Department of Medical and Health Sciences (IMH)/Radiology, Linkoeping (Sweden); Moreno, Rodrigo [Linkoeping University, Center for Medical Image Science and Visualization (CMIV), Linkoeping (Sweden); Linkoeping University, Department of Medical and Health Sciences (IMH)/Radiology, Linkoeping (Sweden); Brismar, Torkel B. [KUS Huddinge, Department of Clinical Science, Intervention and Technology at Karolinska Institutet and Department of Radiology, Stockholm (Sweden)

    2014-02-15

    Bone strength depends on both mineral content and bone structure. The aim of this in vitro study was to develop a method of quantitatively assessing trabecular bone structure by applying three-dimensional image processing to data acquired with multi-slice and cone-beam computed tomography using micro-computed tomography as a reference. Fifteen bone samples from the radius were examined. After segmentation, quantitative measures of bone volume, trabecular thickness, trabecular separation, trabecular number, trabecular nodes, and trabecular termini were obtained. The clinical machines overestimated bone volume and trabecular thickness and underestimated trabecular nodes and number, but cone-beam CT to a lesser extent. Parameters obtained from cone beam CT were strongly correlated with μCT, with correlation coefficients between 0.93 and 0.98 for all parameters except trabecular termini. The high correlation between cone-beam CT and micro-CT suggest the possibility of quantifying and monitoring changes of trabecular bone microarchitecture in vivo using cone beam CT. (orig.)

  5. A comparative evaluation of Cone Beam Computed Tomography (CBCT) and Multi-Slice CT (MSCT). Part II: On 3D model accuracy

    Liang Xin, E-mail: Xin.Liang@med.kuleuven.b [Oral Imaging Centre, School of Dentistry, Oral Pathology and Maxillofacial Surgery, Faculty of Medicine, Catholic University of Leuven (Belgium); College of Stomatology, Dalian Medical University (China); Lambrichts, Ivo, E-mail: Ivo.Lambrichts@uhasselt.b [Department of Basic Medical Sciences, Histology and Electron Microscopy, Faculty of Medicine, University of Hasselt, Diepenbeek (Belgium); Sun Yi, E-mail: Sunyihello@hotmail.co [Oral Imaging Centre, School of Dentistry, Oral Pathology and Maxillofacial Surgery, Faculty of Medicine, Catholic University of Leuven (Belgium); Denis, Kathleen, E-mail: kathleen.denis@groept.b [Department of Industrial Sciences and Techology-Engineering (IWT), XIOS Hogeschool Limburg, Hasselt (Belgium); Hassan, Bassam, E-mail: b.hassan@acta.n [Department of Oral Radiology, Academic Centre for Dentistry Amsterdam (ACTA), Amsterdam (Netherlands); Li Limin, E-mail: Limin.Li@uz.kuleuven.b [Department of Paediatric Dentistry and Special Dental Care, School of Dentistry, Oral Pathology and Maxillofacial Surgery, Faculty of Medicine, Catholic University of Leuven (Belgium); Pauwels, Ruben, E-mail: Ruben.Pauwels@med.kuleuven.b [Oral Imaging Centre, School of Dentistry, Oral Pathology and Maxillofacial Surgery, Faculty of Medicine, Catholic University of Leuven (Belgium); Jacobs, Reinhilde, E-mail: Reinhilde.Jacobs@uz.kuleuven.b [Oral Imaging Centre, School of Dentistry, Oral Pathology and Maxillofacial Surgery, Faculty of Medicine, Catholic University of Leuven (Belgium)

    2010-08-15

    Aim: The study aim was to compare the geometric accuracy of three-dimensional (3D) surface model reconstructions between five Cone Beam Computed Tomography (CBCT) scanners and one Multi-Slice CT (MSCT) system. Materials and methods: A dry human mandible was scanned with five CBCT systems (NewTom 3G, Accuitomo 3D, i-CAT, Galileos, Scanora 3D) and one MSCT scanner (Somatom Sensation 16). A 3D surface bone model was created from the six systems. The reference (gold standard) 3D model was obtained with a high resolution laser surface scanner. The 3D models from the five systems were compared with the gold standard using a point-based rigid registration algorithm. Results: The mean deviation from the gold standard for MSCT was 0.137 mm and for CBCT were 0.282, 0.225, 0.165, 0.386 and 0.206 mm for the i-CAT, Accuitomo, NewTom, Scanora and Galileos, respectively. Conclusion: The results show that the accuracy of CBCT 3D surface model reconstructions is somewhat lower but acceptable comparing to MSCT from the gold standard.

  6. A comparative evaluation of Cone Beam Computed Tomography (CBCT) and Multi-Slice CT (MSCT). Part II: On 3D model accuracy

    Aim: The study aim was to compare the geometric accuracy of three-dimensional (3D) surface model reconstructions between five Cone Beam Computed Tomography (CBCT) scanners and one Multi-Slice CT (MSCT) system. Materials and methods: A dry human mandible was scanned with five CBCT systems (NewTom 3G, Accuitomo 3D, i-CAT, Galileos, Scanora 3D) and one MSCT scanner (Somatom Sensation 16). A 3D surface bone model was created from the six systems. The reference (gold standard) 3D model was obtained with a high resolution laser surface scanner. The 3D models from the five systems were compared with the gold standard using a point-based rigid registration algorithm. Results: The mean deviation from the gold standard for MSCT was 0.137 mm and for CBCT were 0.282, 0.225, 0.165, 0.386 and 0.206 mm for the i-CAT, Accuitomo, NewTom, Scanora and Galileos, respectively. Conclusion: The results show that the accuracy of CBCT 3D surface model reconstructions is somewhat lower but acceptable comparing to MSCT from the gold standard.

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

    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...

  8. The value of multiplanar reconstruction using 64-slice CT myelography in cervical nerve root injury

    Objective: To study the diagnostic value of multi-direction adjusted multiplanar reconstruction (MPR) by 64-slice CT myelography (CTM) in diagnosing cervical nerve injury, and the possibility of the MPR to replace conventional myelography and CT direct-scanning axial images. Methods: Twenty-six patients with cervical nerve root injury were examined by conventional myelography and 64-slice CT using isotropic parameters. Then multi-direction MPR were performed to display nerve roots on coronal and sagittal planes besides axial images. Twenty-six patients were performed surgical operations and diagnosis were obtained. The coincident diagnosing rate with surgical operations results were compared statistically among multi-direction MPR, direct-scanning axial CT images, conventional myelography. The numbers of images were also compared between axial MPR and direct scanning axial CT images. Results: Direct sign of nerve root avulsion was the loss of normal nerve root defect seen in the Isovist filled thecal sac in 64-slice CT, which was found in 31 nerve roots. Indirect signs included: (1) Traumatic pseudomeningocele: 29 nerve roots showed the leak of Isovist into nerve root sheath, and extended into foramina; (2) Arachnoid cyst: 26 nerve roots clearly displays cystic distension in nerve root, which has low-density fine clew form septation from subarachnoid cavity and no nerve root in the cyst; (3) Deformity of the subarachnoid space: deformity of thecal sac, partially lack of Isovist into arachnoid space, which was found in 17 nerve roots. The coincident diagnosing rate of cervical nerve root injury by multi-direction adjusted coronal MPR imaging was 92.6% (50/54), which was higher than by axial CT (77.8%, 42/54) and conventional myelography (68.5%, 37/54), There was significant difference between the conventional myelography, direct-scanning axial CT, multi-direction MPR images (Kappa=0.686, 0.772, 0.920, respectively, P<0.05), the coronal MPR imaging was significantly

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

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

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

    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.

  11. 多层螺旋CT在先天性心脏病的应用现状%Application of multi-slice computed tomography in congenital heart disease

    陈险峰; 马小静; 江帆; 李林

    2014-01-01

    Congenital heart disease belongs to abnormal embryonic development of cardiovascular malformation. It has a lot of changes in pathology. So, it is very important to have a preoperative diagnosis before the operation. Multi-slice computed tomography (MSCT) can analyze illness comprehensive and provide significant proof for clinic. This article expounded the value and situation of it from the historical process of congenital heart disease, the way of check, the characteristic of diagnostic imaging and radiation dose. Clinical practice shows that the imaging advantage of MSCT apply to diagnose complex congenital heart disease. Meanwhile, we should use all kinds of technology to optimize scanning parameters, plan characteristic medical treatments and maximum lower the subjects' radiation dosage.%先天性心脏病属于胚胎发育异常的心血管畸形,其病理改变千差万别,术前诊断对手术治疗尤为重要;多层螺旋 CT 检查能全面分析疾病,为临床提供重要诊断依据。本文从多层螺旋CT检查复杂CHD的历史进程、检查方法、影像诊断特点、辐射剂量的控制四个方面阐述其应用现状。临床实践表明多层螺旋CT的成像优势适用于复杂CHD的诊断,同时应使用各种技术优化扫描参数,制订个性化检查方案,最大限度地降低受检者的辐射剂量。

  12. The evaluation of anti-angiogenic treatment effects for implanted rabbit VX2 breast tumors using functional multi-slice spiral computed tomography (f-MSCT)

    Lei Zhen, E-mail: leizhen2004@163.com [Department of Anatomy, Chinese Medical University, No. 92, Beiermalu Road, Heping District, Shenyang, 110001 (China) and Department of Radiology, The First Hospital of Liaoning Medical College, No. 2, Wuduan, Renmin Street, Jinzhou, 121001 (China); Ma Heji, E-mail: maheji9831@sina.com [Department of Radiology, The First Hospital of Liaoning Medical College, No. 2, Wuduan, Renmin Street, Jinzhou, 121001 (China); Xu Na, E-mail: xuna821230@sohu.com [Department of Radiology, The First Hospital of Liaoning Medical College, No. 2, Wuduan, Renmin Street, Jinzhou, 121001 (China); Xi Huanjiu, E-mail: xihuanjiu2004@yahoo.cn [Anthropology Institute, Liaoning Medical College, No. 40, Sanduan, Songpo Rd, Jinzhou, 121001 (China)

    2011-05-15

    Objective: Investigate the benefit of functional multi-slice spiral computed tomography (f-MSCT) perfusion imaging in the non-invasive assessment of targeted anti-angiogenesis therapy on an implanted rabbit VX2 breast tumor model. Method: 69 female pure New Zealand white rabbits were randomly assigned to one of the 4 groups and received treatment accordingly: control (saline), Endostar, neoadjuvant chemotherapy (Cyclophosphamide, Epirubicin and 5-Fluorouracil, CEF), combination therapy (Endostar and CEF). After 2 weeks of treatment, f-MSCT perfusion scannings were performed for all rabbits and information about blood flow (BF), blood volume (BV), mean transit time (MTT) and surface permeability (SP) was collected. After perfusion imaging, tumor tissues were sampled for immunohistochemistry and the Western blot test of VEGF protein expression. Results: (1) The VEGF expression level, measured by immunohistochemistry and Western blot, decreased by treatment group (control > Endostar > CEF > combination therapy). The same was true for the mean BF, BV, MTT and PS, which decreased from the control group to the combination therapy group gradually. The mean MTT level increased in reverse order from the control to the combination therapy group. The difference between any 2 groups on these measures was statistically significant (P < 0.05). (2) There was moderate positive correlation between VEGF expression and BE, BV, or PS level (P < 0.05) and a negative correlation between VEGF expression and MTT level for all 4 groups (P < 0.05). Conclusion: Therefore, f-MSCT can be used as a non-invasive approach to evaluate the effect of anti-angiogenic therapy for implanted rabbit VX2 breast tumors.

  13. The evaluation of anti-angiogenic treatment effects for implanted rabbit VX2 breast tumors using functional multi-slice spiral computed tomography (f-MSCT)

    Objective: Investigate the benefit of functional multi-slice spiral computed tomography (f-MSCT) perfusion imaging in the non-invasive assessment of targeted anti-angiogenesis therapy on an implanted rabbit VX2 breast tumor model. Method: 69 female pure New Zealand white rabbits were randomly assigned to one of the 4 groups and received treatment accordingly: control (saline), Endostar, neoadjuvant chemotherapy (Cyclophosphamide, Epirubicin and 5-Fluorouracil, CEF), combination therapy (Endostar and CEF). After 2 weeks of treatment, f-MSCT perfusion scannings were performed for all rabbits and information about blood flow (BF), blood volume (BV), mean transit time (MTT) and surface permeability (SP) was collected. After perfusion imaging, tumor tissues were sampled for immunohistochemistry and the Western blot test of VEGF protein expression. Results: (1) The VEGF expression level, measured by immunohistochemistry and Western blot, decreased by treatment group (control > Endostar > CEF > combination therapy). The same was true for the mean BF, BV, MTT and PS, which decreased from the control group to the combination therapy group gradually. The mean MTT level increased in reverse order from the control to the combination therapy group. The difference between any 2 groups on these measures was statistically significant (P < 0.05). (2) There was moderate positive correlation between VEGF expression and BE, BV, or PS level (P < 0.05) and a negative correlation between VEGF expression and MTT level for all 4 groups (P < 0.05). Conclusion: Therefore, f-MSCT can be used as a non-invasive approach to evaluate the effect of anti-angiogenic therapy for implanted rabbit VX2 breast tumors.

  14. Genetic association of glutathione peroxidase-1 with coronary artery calcification in type 2 diabetes: a case control study with multi-slice computed tomography

    Fujimoto Kei

    2007-09-01

    Full Text Available Abstract Background Although oxidative stress by accumulation of reactive oxygen species (ROS in diabetes has become evident, it remains unclear what genes, involved in redox balance, would determine susceptibility for development of atherosclerosis in diabetes. This study evaluated the effect of genetic polymorphism of enzymes producing or responsible for reducing ROS on coronary artery calcification in type 2 diabetes (T2D. Methods An index for coronary-arteriosclerosis, coronary artery calcium score (CACS was evaluated in 91 T2D patients using a multi-slice computed tomography. Patients were genotyped for ROS-scavenging enzymes, Glutathione peroxidase-1 (GPx-1, Catalase, Mn-SOD, Cu/Zn-SOD, as well as SNPs of NADPH oxidase as ROS-promoting elements, genes related to onset of T2D (CAPN10, ADRB3, PPAR gamma, FATP4. Age, blood pressure, BMI, HbA1c, lipid and duration of diabetes were evaluated for a multivariate regression analysis. Results CACS with Pro/Leu genotype of the GPx-1 gene was significantly higher than in those with Pro/Pro (744 ± 1,291 vs. 245 ± 399, respectively, p = 0.006. In addition, genotype frequency of Pro/Leu in those with CACS ≥ 1000 was significantly higher than in those with CACS OR = 3.61, CI = 0.97–13.42; p = 0.045 when tested for deviation from Hardy-Weinberg's equilibrium. Multivariate regression analyses revealed that CACS significantly correlated with GPx-1 genotypes and age. Conclusion The presence of Pro197Leu substitution of the GPx-1 gene may play a crucial role in determining genetic susceptibility to coronary-arteriosclerosis in T2D. The mechanism may be associated with a decreased ability to scavenge ROS with the variant GPx-1.

  15. Preliminary evaluation of 64-slice spiral CT coronary angiography in patients with coronary artery disease

    Objective: To investigate the image quality and diagnostic accuracy using 64-slice spiral computed tomography (64-CTA) scanner in patients with suspected coronary artery disease. Methods: Sixty eight patients with chest pain or post PTCA underwent CT coronary angiography (CTA) and selected coronary angiography (SCA). The SCA results were served as 'gold standard' to evaluate the diagnostic accuracy of CTA, while the sensitivity, positive predictive value (PPV) and negative predictive value (NPV) were calculated, respectively. Results: 64-slice spiral CT could clearly demonstrate the coronary arterial trunk and branchs with stenosis, calcifications abnormal orifise origination and bridge vascular disease; especially with high accuracy in revealing calcification and even with quantification. The sensitivity, specificity, PPV and NPV of the degree of stenosis more than 75% for coronary artery segments evaluated by CTA were significantly higher than those of the degree of stenosis less than 50% for coronary artery segments (P<0.01). Conclusion: CTA is a safe, simple and reliable noninvasive method for screening coronary artery disease in patients with chest pain. Moreover, 64-slice spiral CT could demonstrate not only the more delicate delineation of coronary arterial changes with 3D reconstruction and volume renderting but also the presence and quantity of calcium deposited on the vascular wall. (authors)

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

    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.

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

    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.

  18. Noninvasive detection of coronary abnormalities in pediatric patients with Kawassaki disease using multi-slice spiral CT

    Objective: To evaluate the feasibility and value of detecting coronary artery lesions in Kawasaki disease using multi-slice computed tomography (MSCT). Methods: Thirty-four pediatric patients underwent 16-slice or 64-slice CT coronary, angiography. 18 patients were also examined with 2 dimension echocardiography (2DE). In all cases, visibility of coronary artery segment was recorded. The diameter of the LCA, RCA were measured in MSCTA and compared with 2DE. Correlation coefficient of dimension and coincidence rate of two methods were calculated. Results: Coronary artery lesions were found in 14 patients (22 branches) of the 34 cases with KD on MSCT. Six cases were dialated, 3 cases were dialated with aneurysms, 2 cases had aneurysms without dialation. Coronary artery stenosis in 1 eases, calcification in 2 cases. Three cases had multiple aneurysms with the presence of alternate stenosis that made the artery a bead-like appearance. CC of LM and RCA were 0.85, 0.91, respectively (P>0.05). Three coronary artery aneurysm in the distal RCA was missed by 2DE. MSCT could not detect slight or moderate mitral regurgitation in 2 patients and artery wall thickening in 5 patients. Conclusion: MSCT would be an effective complementary or alternative method for CDEC to evaluate coronary artery lesions non-invasively in pediatric patients with Kawasaki disease. (authors)

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

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

  20. Beam-hardening correction for virtual monochromatic imaging of myocardial perfusion via fast-switching dual-kVp 64-slice computed tomography. A pilot study using a human heart specimen

    Investigate the effectiveness of beam-hardening (BH) correction using ECG-gated dual-kVp computed tomography (CT) for myocardial imaging. A human heart specimen and artificial descending aorta were scanned using both dual-kVp and single 120-kVp modes. The myocardial CT values at the anterior and posterobasal walls were 89.4±6.2 and 87.1±6.9 hounsfield unit (HU) (P=0.59) for the 69-keV images, and 88.3±5.9 and 49.9±13.5 HU (P=0.002) for the 120-kVp images, respectively. Fast-switching dual-kVp technology is feasible for the correction of CT value deficits induced by BH that mimics perfusion defects. (author)

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

    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.)

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

    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.)

  3. 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

    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

  4. Introduction to coronary imaging with 64-slice Computed Tomography

    The aim of this article is to illustrate the main technical improvements in the last generation of 64-row CT scanners and the possible applications in coronary angiography. In particular, we describe the new physical components (X-ray tube-detectors system) and the general scan and reconstruction parameters. We then define the scan protocols for coronary angiography with the new generation of 64-row CT scanners to enable radiologists to perform a CT study on the basis of the diagnostic possibilities

  5. Virtual endoscopy of the middle ear: experimental and clinical results of a standardised approach using multi-slice helical computed tomography

    Virtual endoscopy (VE) enables non-invasive 3D endoluminal imaging of the middle ear by post-processing of CT data. To optimise the clinical application a standardised approach was evaluated in normal and pathologic cases. Data acquisition was performed using multi-slice helical CT in 20 normal patients and 15 patients with malformation or trauma. Virtual endoscopy of the tympanic cavity and 3D images of the ossicles were generated using surface and volume rendering. Qualitative assessment of the representation of anatomical structures was performed in normal patients. In 15 pathological cases the diagnostic benefit was evaluated by comparing the 3D images to the 2D images and intra-operative findings. In all 35 cases 3D imaging was possible using the standardised approach. The ossicular chain as well as the bony and soft tissue structures of the tympanic cavity were visualised in 20 normal patients. In 7 of 8 patients with malformation and 1 of 7 patients with trauma the original diagnosis was changed by 3D imaging. Standardisation and evaluation of the method in normal patients is essential as it enhances the diagnostic reliability. Virtual endoscopy facilitates understanding of the complex anatomy of the middle ear. In cases of suspected malformation and confirmed trauma it is helpful for diagnosis and surgical planning. (orig.)

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

    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

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

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

    2006-04-15

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

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

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

    2006-03-15

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

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

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

  10. Application of Multi-slice Spiral Computed Tomography To Diagnose Hyoid Fracture%多层螺旋CT对舌骨骨折的临床应用价值

    周建中; 石士奎; 季立平

    2008-01-01

    目的 探讨多层螺旋CT(multi-slice spiral computed tomography,MSCT)对舌骨骨折的诊断价值,提高对舌骨骨折临床重要性的认识.方法 回顾性分析6例舌骨骨折的MSCT及临床表现特点.结果 本组6例舌骨骨折中,舌骨大角骨折1例,舌骨体部骨折1例,舌骨大角与体部连接处骨折4例,其中舌骨大角与体部连接处骨折MSCT仅表现为连接处间隙增宽、错位,未见明确骨皮质连续性中断征象.结论 MSCT对舌骨骨折具有重要的诊断价值,对可疑舌骨骨折患者应行MSCT检查.

  11. Prevalence of anatomical variants and coronary anomalies in 543 consecutive patients studied with 64-slice CT coronary angiography

    Cademartiri, Filippo; La Grutta, Ludovico; Malagò, Roberto; Alberghina, Filippo; Meijboom, Willem B.; Pugliese, Francesca; Maffei, Erica; Palumbo, Anselmo Alessandro; Aldrovandi, Annachiara; Fusaro, Michele; Brambilla, Valerio; Coruzzi, Paolo; Midiri, Massimo; Mollet, Nico R. A.; Krestin, Gabriel P

    2008-01-01

    The aim of our study was to assess the prevalence of variants and anomalies of the coronary artery tree in patients who underwent 64-slice computed tomography coronary angiography (CT-CA) for suspected or known coronary artery disease. A total of 543 patients (389 male, mean age 60.5 ± 10.9) were reviewed for coronary artery variants and anomalies including post-processing tools. The majority of segments were identified according to the American Heart Association scheme. The coronary dominanc...

  12. Evaluation of peripheral artery stent with 64-slice multi-detector row CT angiography: Prospective comparison with digital subtraction angiography

    Li Xiaoming, E-mail: lixiaoming55@hotmail.co [Department of Radiology, Changhai Hospital, Second Military Medical University, Shanghai 200433 (China); Department of Radiology, Xin Hua Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200092 (China); Li Yuhua, E-mail: liyuhua2000@hotmail.co [Department of Radiology, Xin Hua Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200092 (China); Tian Jianming, E-mail: tianjianming1952@hotmail.co [Department of Radiology, Changhai Hospital, Second Military Medical University, Shanghai 200433 (China); Xiao Yi, E-mail: xiaoyi@188.co [Department of Radiology, Changhai Hospital, Second Military Medical University, Shanghai 200433 (China); Lu Jianping, E-mail: lujianping2000@hotmail.co [Department of Radiology, Changhai Hospital, Second Military Medical University, Shanghai 200433 (China); Jing Zaiping, E-mail: jingzaiping@hotmail.co [Department of Vascular Surgery, Changhai Hospital, Second Military Medical University, Shanghai 200433 (China); Sheng Jing, E-mail: shengjing1997@hotmail.co [Department of Radiology, Changhai Hospital, Second Military Medical University, Shanghai 200433 (China); Edwin, Angela, E-mail: angiedwin@yahoo.co [Department of Emergency, 34 Military Hospital, Wilberforce Barracks, Republic of Sierra Leone Armed Forces, Freetown (Sierra Leone); Wu Fanghong, E-mail: fanghong.wu@siemens.co [Medical Solutions, Shanghai Branch, Siemens Ltd. (China)

    2010-07-15

    Purpose: To assess the accuracy of 64-slice multi-detector row computed tomography (MDCT) angiography in the evaluation of peripheral artery in-stent or peristent restenosis, with conventional digital subtraction angiography (DSA) as the reference standard. Materials and methods: Forty-one patients (30 men, 11 women; mean age, 69.8 {+-} 9.2 years) with symptomatic peripheral arterial occlusive disease after peripheral artery stenting (81 stented lesions) underwent both conventional DSA and 64-slice MDCT angiography. Each stent was classified as evaluable or unevaluable, and every stent was divided into three segments (proximal stent, stent body, and distal stent), resulting in 243 segments. For evaluation, stenosis was graded as follows: 1, none or slight stenosis (<25%); 2, mild stenosis (25-49%); 3, moderate stenosis (50-74%); 4, severe stenosis or total occlusion ({>=}75%). Two readers evaluated all CT angiograms with regard to narrowing of in-stent or peristent restenosis by consensus. Results were compared with findings of the DSA. Results: Of 81 stents, 62 (76.5%) were determined to be assessable. The metal artifact of the gold marker and motion artifact increased uninterpretability of the images of stents. Overall, 24 of 28 in-stent restenosis and 38 of 53 persistent restenosis were correctly detected by MDCT (85.7% and 71.7% sensitivity). In evaluable stents, 21 of 22 in-stent restenoses and 27 of 28 persistent restenosis were correctly detected (95.4% and 96.4% sensitivity). Additionally, as the grade of stenosis increases, the mean level of CT values in the stent lumina decreases linearly accordingly. Conclusion: 64-Slice MDCT has a high accuracy for the detection of significant in-stent or peristent restenosis of assessable stents in patients with peripheral artery stent implantation and therefore can be considered as a valuable noninvasive technique for stent surveillance.

  13. Evaluation of peripheral artery stent with 64-slice multi-detector row CT angiography: Prospective comparison with digital subtraction angiography

    Purpose: To assess the accuracy of 64-slice multi-detector row computed tomography (MDCT) angiography in the evaluation of peripheral artery in-stent or peristent restenosis, with conventional digital subtraction angiography (DSA) as the reference standard. Materials and methods: Forty-one patients (30 men, 11 women; mean age, 69.8 ± 9.2 years) with symptomatic peripheral arterial occlusive disease after peripheral artery stenting (81 stented lesions) underwent both conventional DSA and 64-slice MDCT angiography. Each stent was classified as evaluable or unevaluable, and every stent was divided into three segments (proximal stent, stent body, and distal stent), resulting in 243 segments. For evaluation, stenosis was graded as follows: 1, none or slight stenosis (<25%); 2, mild stenosis (25-49%); 3, moderate stenosis (50-74%); 4, severe stenosis or total occlusion (≥75%). Two readers evaluated all CT angiograms with regard to narrowing of in-stent or peristent restenosis by consensus. Results were compared with findings of the DSA. Results: Of 81 stents, 62 (76.5%) were determined to be assessable. The metal artifact of the gold marker and motion artifact increased uninterpretability of the images of stents. Overall, 24 of 28 in-stent restenosis and 38 of 53 persistent restenosis were correctly detected by MDCT (85.7% and 71.7% sensitivity). In evaluable stents, 21 of 22 in-stent restenoses and 27 of 28 persistent restenosis were correctly detected (95.4% and 96.4% sensitivity). Additionally, as the grade of stenosis increases, the mean level of CT values in the stent lumina decreases linearly accordingly. Conclusion: 64-Slice MDCT has a high accuracy for the detection of significant in-stent or peristent restenosis of assessable stents in patients with peripheral artery stent implantation and therefore can be considered as a valuable noninvasive technique for stent surveillance.

  14. Assessment of extracranial-intracranial bypass patency with 64-slice multidetector computerized tomography angiography

    Extracranial-intracranial (EC/IC) bypass is a useful procedure for the treatment of cerebral vascular insufficiency or complex aneurysms. We explored the role of multidetector computed tomography angiography (MDCTA), instead of digital subtraction angiography (DSA), for the postoperative assessment of EC/IC bypass patency. We retrospectively analyzed a consecutive series of 21 MDCTAs from 17 patients that underwent 25 direct or indirect EC/IC bypass procedures between April 2003 and November 2007. Conventional DSA was available for comparison in 13 cases. MDCTA used a 64-slice MDCT scanner (Aquilion 64, Toshiba). The proximal and distal patencies were analyzed independently on MDCTA and DSA by a neuroradiologist and a neurosurgeon. The bypass was considered patent when the entire donor vessel was opacified without discontinuity from proximal to distal ends and was visibly in contact with the recipient vessel. MDCTA depicted the patency status in every patient. Bypasses were patent in 22 cases, stenosed in one, and occluded in two. DSA always confirmed the results of the MDCTA (sensitivity = 100%, 95% CI = 0.655-1.0; specificity 100%, 95% CI = 0.05-1.0). MDCTA is a non-invasive and accurate exam to assess the postoperative EC/IC bypass patency and is a promising technique in routine follow-up. (orig.)

  15. Study of CdTe:Cl and CdZnTe detectors for medical multi-slices X-ray Computed Tomography

    The application of CdTe and CdZnTe detectors to medical X-ray Computed Tomography have been investigated. Different electrodes (Au, Pt, In) have been deposited on CdZnTe HPBM and on CdTe:ClTHM. Their injection properties have been determined with Current-Voltage characteristics. Under X-ray in CT conditions, injection currents measurements reveal trapped carriers space-charges formation. The same way, the comparisons of the responses to X-beam cut-off with various injection possibilities enable to follow the space-charges evolutions and then to determine the predominant traps types. Nevertheless, both hole and electron traps are responsible for the memory effect e.g. the currents levels dependence with irradiation history. This effect is noticed in particular on responses to fast flux variations that simulate scanner's conditions. Trap levels probably corresponding to native defects are responsible for these limitations. In order to make such detectors suitable for X-ray Computed Tomography, significant progresses in CdTe for CdZnTe crystal growth with an important defects densities reduction (factor 10), or possibly counting mode operation, seem necessary. (author)

  16. High-resolution multi-slice PET

    This report evaluates the progress to test the feasibility and to initiate the design of a high resolution multi-slice PET system. The following specific areas were evaluated: detector development and testing; electronics configuration and design; mechanical design; and system simulation. The design and construction of a multiple-slice, high-resolution positron tomograph will provide substantial improvements in the accuracy and reproducibility of measurements of the distribution of activity concentrations in the brain. The range of functional brain research and our understanding of local brain function will be greatly extended when the development of this instrumentation is completed

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

    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.

  18. A study on optimal scan conditions of big bore multi-slice computed tomography based on radiation dose and image noise

    The newly introduced Big Bore computed tomography (CT) has a possibility to increase the tube current product scan time (mA s) for compensation of image degradation due to larger gentry opening without sound guideline. The objective of this paper is to derive optimal scan conditions for Big Bore CT scanner, mainly relating to the dose of diagnostic CT. The weighted CT dose index (CTDIw) was estimated at five typical protocols, such as head and neck, brain, paediatric, chest and abdomen. Noises were analysed in a circle of 1 or 2 cm of diameter in CT image slice. The results showed that measured CTDIw values generally follow the theoretical rule at all scanning conditions of every protocol. Although image noises decrease with increment of mA s, analysed image noises do follow the theoretical rule, but only in specific protocols. This phenomenon is presumed to result from the photon energy spectra arriving at the detection system of the Big Bore scanner. (authors)

  19. 64-slice CT imaging in a case of total anomalous pulmonary venous circulation

    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

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

    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.

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

    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...

  2. Unsupervised motion-compensation of multi-slice cardiac perfusion MRI

    Stegmann, M.B.; Ólafsdóttir, H; Larsson, H.B.W.

    2005-01-01

    This paper presents a novel method for registration of single and multi-slice cardiac perfusion MRI. Utilising off-line computer intensive analyses of variance and clustering in an annotated training set, the presented method is capable of providing registration without any manual interaction in...... holds great promise for the automation of cardiac perfusion investigations, due to its accuracy, robustness and generalisation ability...

  3. Unsupervised motion-compensation of multi-slice cardiac perfusion MRI

    Stegmann, Mikkel Bille; Ólafsdóttir, Hildur; Larsson, Henrik B. W.

    2005-01-01

    This paper presents a novel method for registration of single and multi-slice cardiac perfusion MRI. Utilising computer intensive analyses of variance and clustering in an annotated training set off-line, the presented method is capable of providing registration without any manual interaction in...... holds great promise for the automation of cardiac perfusion investigations, due to its accuracy, robustness and generalisation ability....

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

    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)

  5. The value of 64-slice CT angiography in diagnosing spinal vascular malformations

    Objective: To evaluate 64-slice CT angiography in diagnosing spinal vascular malformations. Methods: Fifteen patients, who were suggestive of spinal vascular malformations by clinical manifestation and MRI, underwent CT angiography with a 64-slice spiral CT (GE lightspeed VCT). DSA were performed later within 1 week in all the patients and four of them were treated with operation as well. We evaluated CTA images in displaying the lesions according to the following aspects: the type of malformation, lesion range, feeding artery, draining vein and possible fistula, and compared those details with DSA and operation findings. Results: All 15 patients acquired their final diagnosis by DSA and operation, which were intramedullary artefiovenous malformation in 6 cases, perimedullary artefiovenous fistula in 2, spinal dural arteriovenous fistula in 3 and Cobb syndrome in 4 cases. CTA was consistent with DSA in the classification of lesions and in the determination of the involved regions and it revealed the main feeding arteries and draining veins in all patients. CTA showed four arteriovenous fistulae confirmed by DSA, but it failed in a complex arteriovenous fistula. In Cobb syndrome patients, not only the intramedullary but also paravertebral and subcutenous vascular malformation could be clearly seen on CTA images. Conclusion: 64-slice CT angiography can be a preliminary method in spinal vascular malformation because it can determine the classification and reveal almost all the main lesions quickly, atraumatically. (authors)

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

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

    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.)

  7. 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.

    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

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

    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

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

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

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

    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 surgery.

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

    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

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

    Wang Ximing [Tianjin Medical University, Tianjin City (China) and Shandong Medical Imaging Research Institute, Jinan City, Shandong Province 250021 (China)], E-mail: wxming369@163.com.cn; Wu Lebin [Shandong Medical Imaging Research Institute, Jinan City, Shandong Province 250021 (China); Sun Cong [Shandong Medical Imaging Research Institute, Jinan City, Shandong Province 250021 (China); Shandong University Medical College, Shandong Jinan 250012 (China); Liu Cheng [Shandong Medical Imaging Research Institute, Jinan City, Shandong Province 250021 (China); Chao, Bao-Ting [Shandong University Medical College, Shandong Jinan 250012 (China); Han Bo [Shandong Provincial Hospital Pediatric Department, Shandong, Jinan 250021 (China); Zhang Yunting [Tianjin Medical University, General Hospital MR Department, Tianjin City (China); Chen Haisong [Shandong Medical Imaging Research Institute, Jinan City, Shandong Province 250021 (China); Shandong University Medical College, Shandong Jinan 250012 (China); Li Zhenjia [Shandong Medical Imaging Research Institute, Jinan City, Shandong Province 250021 (China)

    2007-11-15

    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.

  13. Improvement of Efficiency and Flexibility in Multi-slice Helical CT

    SUN Wen-wu; CHEN Si-ping; ZHUANG Tian-ge

    2008-01-01

    One of the main aspects in computed tomography (CT) development is to make CT rapidly scan a large longitudinal volume with high z-axis resolution. The combination of helical scanning with multi-slice CT is a promising approach. Image reconstruction in multi-slice CT becomes, therefore, the major challenge. Known algorithms need to derive the complementary data or work only for certain range of pitches. A reconstruction algorithm was presented that works with the direct data as well as arbitrary pitches. Filter interpolation based on the proposed method was implemented easy. The results of computer simulations under kinds of conditions for four-slice CT were presented. The proposed method can obtain higher efficiency than the conventional method.

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

    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)

  15. Multi-slice spiral CT 3D reconstruction of extrahepatic feeding arteries in hepatocellular carcinoma:its clinical applications

    Objective: To discuss the feasibility of displaying the extrahepatic feeding arteries in hepatocellular carcinoma with the help of multi-slice spiral CT 3D reconstruction and to assess the clinical value of this technique. Methods: Triple-phase enhanced CT scanning with a 64-slice spiral CT scanner was performed in 89 patients with advanced primary hepatocellular carcinoma (HCC). Three-dimensional reconstruction techniques, including maximum intensity projection (MIP) and volume rendering (VR), with arterial phase images, were used to display the origination and course of both the intrahepatic and extrahepatic supplying arteries of HCC. The results were compared with the angiographic findings. Results: Of 59 cases with massive type HCC, extrahepatic supplying arteries were found in 33. In 21 cases of diffuse type HCC four showed extrahepatic supplying arteries,and in nine cases of nodular type HCC only one had extra-hepatic supplying arteries. The HCC could get their extrahepatic blood supply via eight pathways. A total of 44 extrahepatic supplying arteries were detected,and 19 anomalously originated hepatic arteries were found. Conclusion: The extrahepatic supplying arteries in hepatocellular carcinoma are common findings and their supplying pattern are extremely varied, which may be associated with the type and location of the tumors. Three-dimensional reconstruction technique with the help of triple-phase enhanced CT scanning on a 64-slice spiral CT scanner can provide excellent images as vivid and ideal as angiography can afford. Therefore,the times of angiography examination, the use of contrast media as well as the dose of radiation to both the patients and the physicians can be reduced as far as possible. The detailed information about extrahepatic blood supply is very useful for improving the therapeutic result of HCC. (authors)

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

    Jun Sung Moon

    2013-02-01

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

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

    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)

  18. Hybrid cardiac SPECT/64-slice CTA-derived LV function parameters: Correlation and reproducibility assessment

    The purpose of this study is to define the relationship between SPECT and CTA measured parameters of left ventricular (LV) function and volumes obtained in a single session using SPECT/64-slice CT hybrid imaging device, and in addition, to assess the reproducibility of LV parameters measured using 64-slice CTA. Materials and methods: Seventy-six patients with suspected or known coronary artery disease underwent cardiac CTA and GSPECT in one session using a hybrid SPECT/CT device. LV end-diastolic volume (EDV), end-systolic volume (ESV) and ejection fraction (EF) were measured on each component of the hybrid device. For the CTA component, these parameters were re-measured by the same investigator and by a second investigator with an interval of 3-54 weeks. Corresponding GSPECT and CTA measured parameters were compared. For CTA, intra-observer and inter-observer variability of LV function and volume measurements were calculated. Results: A very good correlation was found between the GSPECT and CTA measured LVEF (r = 0.81), ESV (r = 0.90) and EDV (r = 0.82). There was a small positive difference by CTA measured LVEF (3.9 ± 14.2%), and more prominent positive differences by CTA measured ESV and EDV (9.8 ± 14.8 and 44.9 ± 23.1 cm3, respectively). There was excellent reproducibility in the measurements of all parameters with very low intra- and inter-observer variability (r = 0.93 for EF and 0.98 for EDV and ESV). Conclusions: Although a good correlation was found between the EF measurements obtained from CTA and SPECT, interchangeable use of EF measurements between the two modalities should be done cautiously and interchangeable use of LV EDV and ESV should be avoided.

  19. The study of temporal bone scanning at low-dose with 64-slice spiral CT

    Objective: To study the rationality and possibility of 64 slice spiral CT in the examination of the temporal bone at low dose. Methods: The same CT technique and temporal bone mode as those for clinical CT were used, two cranium specimens (four ears) were scanned with Somatom Sensation 64-slice spiral CT at different mA (380, 300, 200, 160, 120, 80), and multi-planar reformation was performed. The CT dose index at different mA groups were measured by 10 em pencil ionization chamber and head dose phantom. Four anatomic structures on axial images (subarcuate fossa, tendon of tensor tympani, facial recess, etc), four anatomic structures on coronal images (scute, crista transversa, fenestra cochleae, etc) and six anatomic structures on double oblique images (malleus, incus, stirrup bone, upper bony semicircular, etc) were chosen to evaluate and grade the reformation images among different mA groups, and to determine the minimum mA value. Ten ears of five patients were used to test the validity of the minimum mA value. Results: CT radiation dose was significantly reduced flora (47.8 ± 2.7) to (20.1 ± 2.0) mGy (P<0.01) when mA decreased from 380 mA to 160 mA. No significant difference in displaying anatomic structures between the two mA protocols. Conclusion: it is a feasible borne temporal scanning method to decrease the radiation dose by decreasing mA appropriately. (authors)

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

    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

  1. Clinical evaluation of 64-slice CT assessment of global left ventricular function using automated cardiac phase selection

    Left ventricular (LV) function provides prognostic information regarding the morbidity and mortality of patients. An automated cardiac phase selection algorithm has the potential to support the assessment of LV function with computed tomography (CT). This algorithm is clinically evaluated for 64-slice cardiac CT. Examinations of twenty consecutive patients were selected. Electrocardiogram gated contrast-enhanced CT was performed. Reconstructions were performed using an automated and a manual method, followed by the determination of the global LV function. Significances were tested using 2-sided Student's t-tests. Reduction in post processing time and storage capacity were estimated. A slightly smaller mean end-systolic volume was found with the automated method (52±18 ml vs 54±17 ml, p=0.02, r=0.99). The mean LV ejection fraction was slightly larger with the automated method (65±8% vs 64±8%, p=0.004, r=0.99). The estimated reduction in post processing time was maximal 5 min per patient with a potential 80% data storage reduction. Results of the automated phase selection algorithm are similar to the manual method. The automated tool reduces post processing time, reconstruction time and transfer time. (author)

  2. The relationship between the appearances of colorectal tumor in multi-slices spiral CT and the pathologic histology

    Objective: To evaluate the relationship between the appearances of colorectal tumor in multi-slices spiral-CT and the pathologic histology. Methods: 92 patients with colorectal tumor, who had undergone preoperative MSCT examination, were reviewed retrospectively. The detail information of their appearances in multi-slices spiral CT, the pathologic histology, lymph node metastasis and pericolonic infiltration were analyzed. All the patients were cleaned intestine tracts and were given an enema (2.5% iso-osmia mannitol solution) before undergoing plain scan and portal venous phase enhanced scan with 64-slices spiral-CT Patients were classified into five types according to pathology: well-differentiated, moderately differentiated, poorly differentiated adencarcinoma, mucinous adenocarcinoma and signet-ring cell carcinoma. And then each group's CT features in plain and enhanced scan, lymph node metastasis, remote metastasis and infiltration were analyzed. Eventually, they were categorized into three groups based on their pathology of statistics. The first group was the poorly differentiated adencarcinoma, the second mucinous adenocarcinoma and signet-ring cell carcinoma, and the third well-differentiated and moderately differentiated adenocarcinoma. Results Of all these cases, 74 cases were of moderately differentiated adencarcinoma, and 4 cases of well differentiated adencarcinoma, 6 cases of poorly differentiated adencarcinoma, 7 cases of mucinous adenocarcinoma, only 1 case was of signet-ring cell carcinoma In first group, the average CT value in plain scanning was 41.00±6.39Hu, and 74.83±9.48Hu after contrast enhancement. In second group, the CT value was 39.00±3.46Hu and 73.66±11.66Hu respectively. In third group, the CT value was 44.83±5.95Hu and 85.05±10.47Hu respectively. Statistically significant difference existed comparing the first group with those of the other two groups (p<0.05). Each group's ratio of lymph node metastasis was 50% in first group, 37

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

    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

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

    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

  5. Comparison of digitally reconstructed radiographs (DRRs) generated from 4-slice and 64-slice helical CT scanners, a phantom study

    Full text: Digitally reconstructed radiographs (DRRs) are generated from CT data sets and playa vital role for verifying patient position for many radiotherapy treatments. The present study aimed to investigate the impact on the image quality of DRRs due to changes in the original CT data acquisition; specifically a 4-slice CT scanner and a 64-slice CT scanner have been considered. A specifically designed CT simulation phantom (Nuclear Associates Model 76--417) with test patterns to measure low contrast and modulation transfer function (MTF) was used to evaluate DRR characteristics for Siemens Somatom Sensation 4 and Sensation 64 CT scanners. The phantom was scanned as described in the manufacturer's manual, using the departmental protocol for head CT. The CT images were obtained with 120 kV, 300 mAs, a scanning and reconstruction pitch of I and collimation of I mm. Each of the test patterns from the DRRs was compared for the 4-slice and the 64-slice helical scans. Results The calculated relative MTF (RMTF) showed higher spatial resolution for DRRs generated from 64-slice scans compared with 4-slice scans, Fig. 1. The low contrast values for hole diameter patterns on the DRRs ranged from 0.01-8.04% for 64 slice scans and 0.06-6.15% for 4 slice scans.

  6. Characteristics and diagnostic value of multi-slice spiral computed tomography examination of gastrointestinal lipoma%胃肠道脂肪瘤的多排螺旋CT检查特征与诊断价值

    郑汉朋; 王晓阳; 藤陈迪; 许崇永; 郑祥武; 邱乾德

    2016-01-01

    Objective To investigate the characteristics and diagnostic value of multi-slice spiral computed tomography (MSCT) examination of gastrointestinal lipoma.Methods The cross-sectional study was adopted.The clinicopathological data of 96 patients with gastrointestinal lipoma including 32 from the Second Hospital Affiliated to Wenzhou Medical University,30 from the First Hospital Affiliated to Wenzhou Medical University,17 from the Ruian People's Hospital of Zhejiang,11 from the Yueqing People's Hospital,3 from the Wenzhou Central Hospital and 3 from the Wenzhou People's Hospital from December 2006 to September 2015 were collected.All patients were fasted for 8 hours prior to the examination,and partial patients underwent enhanced scan after the conventional CT scanning with breathless scanning and no abdominal pressure.Coronal and sagittal images of gastrointestinal tract including the tumor were administrated with multiple planar reconstruction (MPR)techniques of Reformat software.Based on MPR images,the curves along the gastrointestinal tract were drawn,voxel distributed along the curve track were reconstructed,and curved planar reconstruction (CPR) images were obtained.The patients received operation or follow-up according to individual characteristics after examinations.The patients undergoing operation were followed up for detecting tumor recurrence and metastasis by CT examination and patients receiving follow-up were observed by endoscopy for detecting changes of tumor size and morphology up to June 2015.The analysis indexes included tumor location and size,performance of MSCT examination (tumor shape,density,margin,intussusceptions,enhanced MSCT examination),intraoperative findings,results of pathological examination and results of follow-up.Measurement data with normal distribution were presented as i ± s.Results All the 96 patients received MSCT plain scan and the 42 received enhanced MSCT scan.The CPR images in 30 patients were collected.(1) Tumor location

  7. Quantitative analyzation of bronchial wall regions using multi slice CT images

    As multi-slice CT develops, there are great expectations for an automatic and computer-support diagnoses. This research is on bronchial area which is composed of the bronchial wall regions and the air regions in the internal bronchial tube. Since to diagnose this is difficult, support diagnosis using CT images is desired. The thickness of bronchial wall changes as the airway of early lung cancer, bronchial asthma and the bronchial enhancing syndrome and others changes into a malignant state. These changes are detected and the thickness of bronchial wall becomes important information. In this research, the extraction accuracy of the algorithm for bronchial wall evaluation is good. (author)

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

    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.

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

    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.

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

    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.

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

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

    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.

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

    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

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

    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)

  14. The value of 64-slice spiral CT angiography based on pre-contrasted raw data in diagnosing pulmonary arteriovenous fistula

    Objective: To evaluate the value of 64-slice spiral CT angiography based on pre- contrasted raw data in diagnosing pulmonary arteriovenous fistula. Methods: 64-slice spiral CT plain scan and enhanced scan was performed in 16 patients with pulmonary arteriovenous fistula, pulmonary angiography based on pre-contrast and post-contrast raw data was performed respectively, including maximum intensity projection (MIP), shaded-surface display (SSD), and volume rendering (VR). According to the results of angiocardiography and surgical findings, comparson of the three methods was made in the display of PAVF in pre-contrast and post-contrast phase images. Results: 8 of the 16 PAVF cases were single lesion, 8 cases were multi-lesions. 30 PAVF lesions were found in all the patients. MIP, SSD and VR based on pre-contrast raw data displayed PAVF lesions in 20, 14, and 22, respectively. The combination of the 3 methods based on pre-contrast raw data could show 26 PAVF lesions. MIP, SSD, and VR based on post-contrast raw data displayed PAVF lesions in 24, 18, and 30, respectively. The combination of the 3 methods based on post-contrast raw data could show 30 PAVF lesions. Conclusion: 64-slice spiral CT angiography based on pre-contrasted raw data can clearly show the position, number, and shape of PAVF lesions, which is of great value in diagnosing PAVF. (authors)

  15. 64-Slice CT Angiography in the Detection of Intracranial Aneurysms: Comparison with DSA and Surgical Findings.

    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

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

    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.

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

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

    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.

  18. The Correlation Between Age and Bleeding Volume in Haemorrhagic Stroke Using Multi Slice CT at District Hospitals in Jakarta

    Saefudin, Tatan; Apriantoro, Nursama Heru; Hidayat, Ekaputra Syarif; Purnamawati, Schandra

    2015-01-01

    Haemorrhagic Stroke is a common disease in Indonesia. The best imaging modality for this disease is Multi Slice Computed Tomography Scanning (MSCT), as it may help strengthening the diagnosis as well as determining the brain bleeding volume. This study aimed to show correlation between bleeding volume of the brain and patient’s age using cross-sectional approach. The 68 samples in this study were taken from secondary data from Head CT Scan of Haemorrhagic Stroke cases. Brain bleeding volume i...

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

    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

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

    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)

  1. Optimization of scanning parameters for multi-slice CT colonography: Experiments with synthetic and animal phantoms

    AIM: To determine the optimal collimation, pitch, tube current and reconstruction interval for multi-slice computed tomography (CT) colonography with regard to attaining satisfactory image quality while minimizing patient radiation dose. MATERIALS AND METHODS: Multi-slice CT was performed on plastic, excised pig colon and whole pig phantoms to determine optimal settings. Performance was judged by detection of simulated polyps and statistical measures of the image parameters. Fat and muscle conspicuity was measured from images of dual tube-current prone/supine patient data to derive a measure of tube current effects on tissue contrast. RESULTS: A collimation of 4x2.5 mm was sufficient for detection of polyps 4 mm and larger, provided that a reconstruction interval of 1.25 mm was used. A pitch of 1.5 allowed faster scanning and reduced radiation dose without resulting in a loss of important information, i.e. detection of small polyps, when compared with a pitch of 0.75. Tube current and proportional radiation dose could be lowered substantially without deleterious effects on the detection of the air-mucosal interface, however, increased image noise substantially reduced conspicuity of different tissues. CONCLUSION: An optimal image acquisition set-up of 4x2.5 mm collimation, reconstruction interval of 1.25 mm, pitch of 1.5 and dual prone/supine scan of 40/100 mA tube current is proposed for our institution for scanning symptomatic patients. Indications are that where CT colonography is used for colonic polyp screening in non-symptomatic patients, a 40 mA tube current could prove satisfactory for both scans

  2. Optimization of scanning parameters for multi-slice CT colonography: Experiments with synthetic and animal phantoms

    Embleton, K.V. E-mail: k.embleton@man.ac.uk; Nicholson, D.A.; Hufton, A.P.; Jackson, A

    2003-12-01

    AIM: To determine the optimal collimation, pitch, tube current and reconstruction interval for multi-slice computed tomography (CT) colonography with regard to attaining satisfactory image quality while minimizing patient radiation dose. MATERIALS AND METHODS: Multi-slice CT was performed on plastic, excised pig colon and whole pig phantoms to determine optimal settings. Performance was judged by detection of simulated polyps and statistical measures of the image parameters. Fat and muscle conspicuity was measured from images of dual tube-current prone/supine patient data to derive a measure of tube current effects on tissue contrast. RESULTS: A collimation of 4x2.5 mm was sufficient for detection of polyps 4 mm and larger, provided that a reconstruction interval of 1.25 mm was used. A pitch of 1.5 allowed faster scanning and reduced radiation dose without resulting in a loss of important information, i.e. detection of small polyps, when compared with a pitch of 0.75. Tube current and proportional radiation dose could be lowered substantially without deleterious effects on the detection of the air-mucosal interface, however, increased image noise substantially reduced conspicuity of different tissues. CONCLUSION: An optimal image acquisition set-up of 4x2.5 mm collimation, reconstruction interval of 1.25 mm, pitch of 1.5 and dual prone/supine scan of 40/100 mA tube current is proposed for our institution for scanning symptomatic patients. Indications are that where CT colonography is used for colonic polyp screening in non-symptomatic patients, a 40 mA tube current could prove satisfactory for both scans.

  3. Multi-slice spiral CT diagnosis of carotid body tumor

    Objective: to explore the Multi-slice spiral CT (MSCT) findings of carotid body tumor (CBT). Methods: Twelve cases of CBT proved by surgery were collected in this study and all patients accepted contrast-enhanced MSCT examination. Two-dimensional and three-dimensional post-processing were performed at diagnostic workstation using Aquilion 1.42. The CT features of CBT were analyzed. Results Each of 12 patients had one lesion. All lesions demonstrated well-marginated masses of homogeneous soft- tissue density with CT value within 29-48 HU on pre-enhanced images. All lesions were markedly enhanced with CT value over 200 HU on arterial-phase images, and the density of lesions decreased rapidly on delay- phase images. Twelve lesions were all located at the level of carotid artery bifurcation, 3 of them enveloping common carotid artery and internal/external carotid artery, and other 9 of them riding right on the carotid bifurcation. Internal carotid artery usually were shifted toward posterior-lateral, and external carotid artery toward anterior or anterior-medial. Conclusion: Contrast-enhanced MSCT examination not only can make a qualitative diagnosis of CBT, but determine its accurate location. It plays an importantly instructional role in clinical diagnosis and treatment. (authors)

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

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

    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.)

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

    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.

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

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

    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.)

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

    Almutairi, Abdulrahman Marzouq [Discipline of Medical Imaging, Department of Imaging and Applied Physics, Curtin University of Technology, Perth, Western Australia (Australia); Sun Zhonghua [Discipline of Medical Imaging, Department of Imaging and Applied Physics, Curtin University of Technology, Perth, Western Australia (Australia)], E-mail: 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.

  8. Multi-slice spiral CT of living-related liver transplantation in children: pictorial essay

    In pediatric living-related liver transplantation, preoperative evaluation of the recipient is important for surgical planning, while the accurate diagnosis of postoperative complications is essential for graft salvage. Multiplanar and three dimensional imaging using multi-slice spiral CT can be used for preoperative vascular imaging, as well as for evaluating postoperative complications. In this essay, we describe the usefulness of multi-slice CT, combined with a variety of different reconstruction techniques, for the preoperative evaluation of transplant recipients. In addition, we demonstrate the multi-slice CT findings of postoperative complications, including vascular stenosis or thrombosis, bile duct leak or stricture, and extrahepatic fluid collection

  9. Multi-slice spiral CT of living-related liver transplantation in children: pictorial essay

    Choi, Seong Hoon; Goo, Hyun Woo; Yoon, Chong Hyun [University of Ulsan College of Medicine, Asan Medical Center, Ulsan (Korea, Republic of)

    2004-09-15

    In pediatric living-related liver transplantation, preoperative evaluation of the recipient is important for surgical planning, while the accurate diagnosis of postoperative complications is essential for graft salvage. Multiplanar and three dimensional imaging using multi-slice spiral CT can be used for preoperative vascular imaging, as well as for evaluating postoperative complications. In this essay, we describe the usefulness of multi-slice CT, combined with a variety of different reconstruction techniques, for the preoperative evaluation of transplant recipients. In addition, we demonstrate the multi-slice CT findings of postoperative complications, including vascular stenosis or thrombosis, bile duct leak or stricture, and extrahepatic fluid collection.

  10. How will the introduction of multi-slice CT affect patient doses?

    Imaging protocols for patients undergoing CT examinations on a conventional single section scanner (GE CT/i) were compared with those developed after a multi-slice scanner (GE LightSpeed) was introduced into clinical practice. For multi-slice CT, the reduction in patient scan time was a more than a factor of two for head scans, and approximately 25% for body scans. The number of images available for review on the multi-slice CT system increased by approximately 40%. Use of this multi-slice CT scanner resulted in an effective dose of 1.2 mSv for head examinations and 9.1 mSv for body examinations. The increase in patient effective dose after the introduction of multi-slice CT was approximately 30% for head CT examinations and 150% for body examinations. Higher patient doses were due to a shorter CT geometry, x-ray beam profiles that are greater than the detector width, and the use of a pitch ratio of only 0.75. Since multi-slice CT offers major reductions in scan time as well as improved image quality, it is anticipated that both individual and collective doses from CT will continue to increase for the foreseeable future. (author)

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

    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.

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

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

    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

  13. Dynamic bowtie filter for cone-beam/multi-slice CT.

    Fenglin Liu

    Full Text Available A pre-patient attenuator ("bowtie filter" or "bowtie" is used to modulate an incoming x-ray beam as a function of the angle of the x-ray with respect to a patient to balance the photon flux on a detector array. While the current dynamic bowtie design is focused on fan-beam geometry, in this study we propose a methodology for dynamic bowtie design in multi-slice/cone-beam geometry. The proposed 3D dynamic bowtie is an extension of the 2D prior art. The 3D bowtie consists of a highly attenuating bowtie (HB filled in with heavy liquid and a weakly attenuating bowtie (WB immersed in the liquid of the HB. The HB targets a balanced flux distribution on a detector array when no object is in the field of view (FOV. The WB compensates for an object in the FOV, and hence is a scaled-down version of the object. The WB is rotated and translated in synchrony with the source rotation and patient translation so that the overall flux balance is maintained on the detector array. First, the mathematical models of different scanning modes are established for an elliptical water phantom. Then, a numerical simulation study is performed to compare the performance of the scanning modes in the cases of the water phantom and a patient cross-section without any bowtie and with a dynamic bowtie. The dynamic bowtie can equalize the numbers of detected photons in the case of the water phantom. In practical cases, the dynamic bowtie can effectively reduce the dynamic range of detected signals inside the FOV. Furthermore, the WB can be individualized using a 3D printing technique as the gold standard. We have extended the dynamic bowtie concept from 2D to 3D by using highly attenuating liquid and moving a scale-reduced negative copy of an object being scanned. Our methodology can be applied to reduce radiation dose and facilitate photon-counting detection.

  14. Value of combining 64 multi-slice spiral computer tomography and serum amyloid A protein in surgical decision-making in rectal cancer%多层螺旋CT联合血清淀粉样蛋白A术前评估直肠癌在外科决策中的价值

    汪晓东; 吕东昊; 宋欢; 秦昌龙; 吴俊华; 李臻辉; 李立

    2009-01-01

    目的 探讨64排多层螺旋CT(MSCT)和血清淀粉样蛋白A(SAA)联合术前评估进行直肠癌术前分期的准确性及其临床应用价值.方法 前瞻性纳入2007年10月至2008年10月期间住院的225例直肠癌患者,将患者随机分为MSCT组和MSCT与SAA联合组,联合组术前行MSCT和SAA联合评估,MSCT组术前只行MSCT评估.分别将两组术前T、N、M、TNM分期准确度进行比较,并比较两组手术方案的预测符合率.结果 本研究实际纳入病例225例,MSCT和SAA联合组110例,MSCT组115例,两组基线情况具有可比性.联合组术前T、N、M和TNM分期的准确度分别为87.3%、85.2%、100%和86.4%,MSCT组的准确度分别为85.2%、67.0%、100%和66.1%;两组术前N分期和TNM分期准确度差异具有统计学意义(P=0.009、0.001).两组手术方案的预测符合率分别为94.7%和81.7%,差异具有统计学意义(P=0.003).结论 MSCT和SAA联合评估的策略可以提高直肠癌患者术前分期N、TNM的准确性,并可提高预测手术方案的符合率.%Objective To determine the accuracy and clinical value of combining 64 multi-slice spiral computer tomography (MSCT) and serum amyloid A protein (SAA) in the preoperative staging of rectal cancer.Methods Prospectively enrolled patients with rectal cancer from October 2007 to October 2008.The patients were randomly assigned into two groups:MSCT and SAA combined group:both MSCT and SAA combinative assessment were performed for preoperative evaluation; MSCT group:only MSCT was performed preoperatively for tumor staging.The accuracy of the preoperative T,N,M,and TNM staging and the concordance rate of predictive operative strategy were compared between the two groups.Results Total of 225 cases with rectal cancer were enrolled in this study.There were 110 cases in MSCT and SAA combined group and 115 cases in MSCT group.The baseline characteristics was comparable between the two groups.For MSCT and SAA combined group,the accuracies of

  15. Ultrafast multi-slice spatiotemporally encoded MRI with slice-selective dimension segmented.

    Zhang, Ting; Chen, Lin; Huang, Jianpan; Li, Jing; Cai, Shuhui; Cai, Congbo; Chen, Zhong

    2016-08-01

    As a recently emerging method, spatiotemporally encoded (SPEN) magnetic resonance imaging (MRI) has a high robustness to field inhomogeneity and chemical shift effect. It has been broadened from single-slice scanning to multi-slice scanning. In this paper, a novel multi-slice SPEN MRI method was proposed. In this method, the slice-selective dimension was segmented to lower the specific absorption rate (SAR) and improve the image quality. This segmented method, dubbed SeSPEN method, was theoretically analyzed and demonstrated with phantom, lemon and in vivo rat brain experiments. The experimental results were compared with the results obtained from the spin-echo EPI, spin-echo SPEN method and multi-slice global SPEN method proposed by Frydman and coauthors (abbr. GlSPEN method). All the SPEN images were super-resolved reconstructed using deconvolution method. The results indicate that the SeSPEN method retains the advantage of SPEN MRI with respect to resistance to field inhomogeneity and can provide better signal-to-noise ratio than multi-slice GlSPEN MRI technique. The SeSPEN method has comparable SAR to the GlSPEN method while the T1 signal attenuation effect is alleviated. The proposed method will facilitate the multi-slice SPEN MRI to scan more slices within one scan with better image quality. PMID:27301072

  16. Ultrafast multi-slice spatiotemporally encoded MRI with slice-selective dimension segmented

    Zhang, Ting; Chen, Lin; Huang, Jianpan; Li, Jing; Cai, Shuhui; Cai, Congbo; Chen, Zhong

    2016-08-01

    As a recently emerging method, spatiotemporally encoded (SPEN) magnetic resonance imaging (MRI) has a high robustness to field inhomogeneity and chemical shift effect. It has been broadened from single-slice scanning to multi-slice scanning. In this paper, a novel multi-slice SPEN MRI method was proposed. In this method, the slice-selective dimension was segmented to lower the specific absorption rate (SAR) and improve the image quality. This segmented method, dubbed SeSPEN method, was theoretically analyzed and demonstrated with phantom, lemon and in vivo rat brain experiments. The experimental results were compared with the results obtained from the spin-echo EPI, spin-echo SPEN method and multi-slice global SPEN method proposed by Frydman and coauthors (abbr. GlSPEN method). All the SPEN images were super-resolved reconstructed using deconvolution method. The results indicate that the SeSPEN method retains the advantage of SPEN MRI with respect to resistance to field inhomogeneity and can provide better signal-to-noise ratio than multi-slice GlSPEN MRI technique. The SeSPEN method has comparable SAR to the GlSPEN method while the T1 signal attenuation effect is alleviated. The proposed method will facilitate the multi-slice SPEN MRI to scan more slices within one scan with better image quality.

  17. Myocardial bridges and mural coronary artery: identification with multi-slice CT versus coronary angiography

    Objective: To compare the feasibility of multi-slices computed tomography (MSCT) versus coronary angiography(CAG) for identification of myocardial bridges and mural coronary artery(MB-MCA). Methods: For 76 patients suspecting coronary heart disease the MSCT and CAG were performed for the coronary imaging. The MB-MCAs were identified on the CT images and angiograms by radiologists and cardiologists separately and independently before and after consulting each other. The data was statistically analyzed using χ2-squrae test. Results: Before consulting each other, 29 MB-MCA in 27 patients and 2 MB-MCA in two cases were detected using MSCT and CAG by radiologists and cardiologist separately and independently with significant difference statistically (χ2 = 10.52, P2=28.82, P2=10.52, P2=-0.33, P<0.05). Conclusion: MSCT is outperformed the CAG in detecting of MB-MCA and the coronary tortuosity on angiograms can be of the suggesting to existing of MB-MCA. (authors)

  18. Three-dimensional image reconstruction for PET by multi-slice rebinning and axial image filtering.

    Lewittt, R M; Muehllehner, G; Karpt, J S

    1994-03-01

    A fast method is described for reconstructing volume images from three-dimensional (3D) coincidence data in positron emission tomography (PET). The reconstruction method makes use of all coincidence data acquired by high-sensitivity PET systems that do not have inter-slice absorbers (septa) to restrict the axial acceptance angle. The reconstruction method requires only a small amount of storage and computation, making it well suited for dynamic and whole-body studies. The method consists of three steps: (i) rebinning of coincidence data into a stack of 2D sinograms; (ii) slice-by-slice reconstruction of the sinogram associated with each slice to produce a preliminary 3D image having strong blurring in the axial (z) direction, but with different blurring at different z positions; and (iii) spatially variant filtering of the 3D image in the axial direction (i.e. 1D filtering in z for each x-y column) to produce the final image. The first step involves a new form of the rebinning operation in which multiple sinograms are incremented for each oblique coincidence line (multi-slice rebinning). The axial filtering step is formulated and implemented using the singular value decomposition (SVD). The method has been applied successfully to simulated data and to measured data for different kinds of phantom (multiple point sources, multiple discs, a cylinder with cold spheres, and a 3D brain phantom). PMID:15551583

  19. Multi-slice CT angiography by triple-phase enhancement in preoperative evaluation of hepatocellular carcinoma

    XIAO Xi-gang; HAN Xue; SHAN Wei-dong; LI An-yuan

    2005-01-01

    Background Triple-phase enhancement of multi-slice computed tomography (MSCT) has markedly improved the diagnostic accuracy of hepatocellular carcinoma (HCC), and MSCT angiography (MSCTA) has been proved useful in detecting vascular anatomy noninvasively. This study aimed to explore the value of MSCTA by triple-phase enhancement in preoperative evaluation of HCC.Methods Fifty-six consecutive cases of primary HCC scheduled for resection were studied with MSCTA by triple-phase enhancement. The raw data images were processed on a workstation for multiplanar reconstruction (MPR) and three-dimensional (3D) reconstruction. The findings after processing of the data were compared with those after surgery or intraoperative sonography. Results The false positive rate of MSCTA by triple-phase enhancement was 10.1% and its false negative rate was 4.3% in detecting HCC. No significant difference was observed in MSCTA and surgery or intraoperative sonography in detecting vascular anatomy anomalies and pathologic variations, whereas significant difference was found in detecting bile duct invasion with MSCT compared to intraoperative sonography.Conclusions MSCTA by triple-phase enhancement not only improves the detection of HCC, but also provides valuable preoperative information about hepatic vascular architecture and parenchyma. MSCTA by triple-phase enhancement is worthy of application as a non-invasive method in preoperative evaluation of HCC.

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

    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

  1. 急性阑尾炎超声与64排螺旋 CT 检查对比分析%The comparative analysis between ultrasound and 64-slice spiral CT examination in acute appendicitis

    王振芳; 岳学旺; 毕言刚; 李飞; 张仕状

    2014-01-01

    目的:探讨超声与64排螺旋 CT 平扫检查在诊断急性阑尾炎中的应用价值。方法收集经手术、病理证实或经保守治疗好转确诊急性阑尾炎的患者65例,术前或治疗前均做了 B 超和 CT 检查,对急性阑尾炎病理改变的显示情况及诊断符合率进行对比分析。结果65例阑尾炎病变,在 CT 图像上正确诊断58例,诊断符合率为89.23%,超声图像正确诊断48例,诊断符合率为73.85%,2种检查方法诊断符合率具有统计学差异(χ2=5.11,P =0.024)。结论多排螺旋 CT 与超声相比在诊断急性阑尾炎方面有较高的诊断符合率。%Objective To investigate the application of ultrasound and 64-slice spiral CT in the diagnosis of acute appendicitis. Methods Sixty-five patients with pathologically or clinally confirmed acute appendicitis were underwent ultrasound and CT examina-tion before operation or conservative treatment.Compared with pathology,the accuracy of CT and B-ultrasound imaging were ana-lyzed.Results Fifty-eight cases were correctly diagnosed by CT and 48 cases were correctly diagnosed by ultrasound,the accuracy was 89.23% (58/65)and 73.85% (48/65),respectively.There was a statistically significant difference between two groups (χ2 =5.1 1,P =0.024).Conclusion The accuracy of multi-slice spiral CT is higher than ultrasound in the diagnosis of acute appendicitis.

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

    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.)

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

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

    2012-03-15

    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.)

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

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

    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

  5. Application of the FDK algorithm for multi-slice tomographic image reconstruction; Aplicacao do algoritmo FDK para a reconstrucao de imagens tomograficas multicortes

    Costa, Paulo Roberto, E-mail: pcosta@if.usp.b [Universidade de Sao Paulo (IFUSP), SP (Brazil). Inst. de Fisica. Dept. de Fisica Nuclear; Araujo, Ericky Caldas de Almeida [Fine Image Technology, Sao Paulo, SP (Brazil)

    2010-08-15

    This work consisted on the study and application of the FDK (Feldkamp- Davis-Kress) algorithm for tomographic image reconstruction using cone-beam geometry, resulting on the implementation of an adapted multi-slice computed tomography system. For the acquisition of the projections, a rotating platform coupled to a goniometer, an X-ray equipment and a digital image detector charge-coupled device type were used. The FDK algorithm was implemented on a computer with a Pentium{sup R} XEON{sup TM} 3.0 processor, which was used for the reconstruction process. Initially, the original FDK algorithm was applied considering only the ideal physical conditions in the measurement process. Then some artifacts corrections related to the projections measurement process were incorporated. The implemented MSCT system was calibrated. A specially designed and manufactured object with a known linear attenuation coefficient distribution ({mu}(r)) was used for this purpose. Finally, the implemented MSCT system was used for multi-slice tomographic reconstruction of an inhomogeneous object, whose distribution {mu}(r) was unknown. Some aspects of the reconstructed images were analyzed to assess the robustness and reproducibility of the system. During the system calibration, a linear relationship between CT number and linear attenuation coefficients of materials was verified, which validate the application of the implemented multi-slice tomographic system for the characterization of linear attenuation coefficients of distinct several objects. (author)

  6. Estimating of patient dose in abdomen-pelvis CT exam as a function of scan techniques in single and multi slice spiral CT by Monte Carlo Method

    Computed tomography is a specialized x-ray imaging technique that has found increasing use since its introduction into diagnostic radiology in the early 1979 's. Although CT is a diagnostic imaging modality giving higher patient dose in comparison with other radiological procedure, but the good resolution of its images, increases the use of this modality in diagnostic imaging with introduction of spiral CT in 1989 and multi slice spiral CT in the early 1990 's, some radiation protection committee tried to calculate the patient dose during CT exam. Since the direct measurement of patient dose and its relation with scan techniques such as mA, KV, Pitch and slice thickness is very difficult , the Monte Carlo method was introduced as the most powerful tool for measuring the organ and patient absorbed dose. Nowadays , the predominant method for assessment of patient's organ absorbed dose is the application of conversion coefficients established by use of Monte Carlo simulation, one of the most famous dose calculation software is CT dosimetry which makes use of the NRPB Monte Carlo dose data sets produced in report SR 250. In this work we use CT Dosimetry Monte Carlo package for measurement of the relationship between the patient dose and scan techniques in mathematically standard phantom( Hermaphrodite 170 cm / 70 Kg) for an abdomen -pelvis scan in single and multi slice spiral CT. As we expected, by increasing the mA and KV the patient dose increases but the relation between the effective dose and mA is linear, also in both kind of scanners the patient dose increases with decreasing the pitch factor. And finally although the multi slice CT is faster than single slice systems, but the patient dose in multi slice systems is more than single slice scanners

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

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

    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

  8. Use of inflammatory factors combined with multi-slice spiral computer tomography for preoperative staging and operative strategy in colon cancer%三种不同炎性因子联合多层螺旋CT对结肠癌术前分期与术式预测的比较研究

    汪晓东; 欧阳书睿; 吕东昊; 刘丹; 李立

    2010-01-01

    Objective To determine the clinical value of C-reactive protein(CRP), fibrinogen (FIB), or serum amyloid A protein (SAA) combined with 64 multi-slice computed tomography (MSCT) for preoperative staging and operative strategy in colon cancer. Methods Patients with colon cancer were prospectively enrolled at the West China Hospital of Sichuan University from November 2007 to July 2009,and were equally randomized into 3 groups undergoing different preoperative evaluation: MSCT combined with CRP(CRP group), MSCT combined with FIB (FIB group), and MSCT combined with SAA (SAA group). The agreement between preoperative staging and postoperative pathologic staging and that between expected surgical procedure and procedure adopted were compared. Results Baseline characteristics among three groups were similar(P>0.05). In CRP group, the accuracies of preoperative staging T, N, M and TNM were 65.7%, 72.4%, 100% and 66.7%, respectively. In FIB group, the accuracies of preoperative staging T, N, M and TNM were 71.4%, 74.3%, 99.0% and 65.7%, respectively. In SAA group, the accuracies of preoperative staging T, N, M and TNM were 60.0%, 55.2%, 96.2%and 51.4%, respectively. The accuracies of N and TNM staging in CRP group and FIB group were significantly higher than those in SAA group(P<0.05). However, there were no significant differences between FIB and CRP group(P>0.05). There were no significant differences in accuracy of predicting surgical procedures among three groups(93.3%, 92.3% and 87.6%, P>0.05). Conclusion Combined assessment of MSCT and CRP or FIB may improve the accuracy of preoperative staging and procedure prediction, and is superior to MSCT combined with SAA.%目的 探讨纤维蛋白原(FIB)、血清淀粉样蛋白(SAA)和C反应蛋白(CRP)联合64排多层螺旋CT(MSCT)在结肠癌术前评估与术式预测中的临床价值.方法 前瞻性纳入2007年11月至2009年7月期间四川大学华西医院结直肠外科专业组

  9. Multi-slice 3D-CTA - an improvement over single slice helical CTA for cerebral aneurysms

    The aim of this study was to demonstrate the utility of volume rendered multi-slice helical three-dimensional CT angiography in patients with cerebral aneurysm when compared with single slice CT angiography and formal digital subtraction angiography. A prototype Toshiba Aquilon multi-slice CT scanner was employed with the following scan conditions: voltage 135 kV; current 300 mA; slice thickness 0.8 mm; scan speed 0.75 sec/cycle; couch speed 1 mm/sec; range 50 mm from foramen magnum; scan pitch 3; three dimensional images were reconstructed using multiple image projections and integral volume rendering algorithms on a Xlink/Xtension workstation. 80 cases of multi-slice CTA for cerebral aneurysm carried out at Fujita University from January 1999 to January 2001 were reviewed. The advantages of multi-slice imaging are illustrated with representative cases of cerebral aneurysm - good demonstration of three dimensional anatomy, appreciation of perforators down to 1 mm in size, delineation of the vessels around the aneurysm complex, relationship between the aneurysm and skull base, information on calcification, thrombus and blebs in the wall and eleven routine views for perusal. Multi-slice CTA is a significant improvement over single slice CTA for cerebral aneurysms. It is our experience the superior and precise images produced by multi-slice technology displays anatomical information not readily available from standard DSA. Multislice 3D-CTA is relatively non-invasive and provides better and adequate detail for surgical planning. The basis of multi-slice CT angiography is described. Multi slice CTA is changing the way cerebral aneurysms are being managed nowadays. New advances in the technology of multi-slice CTA resulting in increased image resolution are outlined. (author)

  10. Multi-slice spiral CT and pathological correlation of renal cell carcinoma

    Objective: To analyze relationship between characteristics on multi-slice spiral CT (MSCT) and pathology of renal cell carcinoma. Methods: Multi-slice spiral CT and surgical pathological results on 32 cases of renal cell carcinoma were retrospectively analyzed. Results: Of the 32 cases, 28 were pathologically diagnosed as clear cell carcinoma, with tumor contrast enhancement similar to the normal cortex in the renal cortical phase (146-175HU), slight contrast washout in the renal parenchyma phase and significant contrast washout from the tumor in the pyelographic phase. Granular cell carcinoma in 4 patients showed no or mild contrast enhancement (38- 55HU) in all three phase. The overall diagnostic accordance rate was 100%, with preoperative staging accordance rate of 96.42%. Conclusion: The triple-phase contrast-enhanced MSCT is useful in predicting the tumor cell type and staging of renal cell carcinoma. (authors)

  11. Diagnosis on multi-slice spiral CT in acute pancreatitis and complications

    Objective: To analyze multi-slice CT features and to assess the diagnostic value of CT in acute pancreatitis. Methods: CT was performed on 21 patients with acute pancreatitis in the unenhanced, arterial (28 seconds after intravenous contrast injection), venous (60 seconds) phases. The morphology and contrast enhancement enhancement patterns were analyzed. Results: Of 21 patients, pancreatic necrosis was found in 9 and acute edematous pancreatitis in 12. Associated findings included bile duct stones or cholecystitis (13), liver abscess (1), systemic lupus erythematosis (1), abdominal trauma (2), and pancreatic divisum (1). Complications included pseudoaneurysm (1), venous thrombosis (1), ascites (7), pleural effusion (4) and right lower lobe lung atelectasis (1). Conclusion: Tri-phasic multi-slice spiral CT can accurately distinguish acute edematous pancreatitis from acute hemorrhagic necrotic pancreatitis. CT allows comprehensive evaluation of the cause and complication of acute pancreatitis. (authors)

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

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

    2006-10-15

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

  13. 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

    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.

  14. 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

    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).

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

    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

  16. Diagnosis of pulmonary embolism and the underlying venous thrombosis by multi-slice CT

    To determine the value of multi-slice CT for the diagnosis of acute pulmonary embolism and an underlying venous thrombosis. Methods: 70 patients with clinically suspected acute pulmonary embolism were examined. Using multi-slice CT a combined examination of the pulmonary arteries and the veins of the lower limb, pelvis and abdomen was performed. Only one single bolus of 150 ml iopromid 300 was injected into a cubital vein with a flow of 4 ml/s. First, the pulmonary arteries were scanned with a slice thickness of 2.5 mm and a pitch of 1.5. On arrival of the contrast medium at the popliteal veins, indicated by bolus trakking, the veins of the lower limbs up to the end of the inferior vena cava were imaged using a slice thickness of 3.75 mm and a pitch of 1.5. The results could be compared with a ventilation-perfusion scan in 48 cases, with a Doppler ultrasound examination in 46 cases, and with a venography in 10 cases. Furthermore, the image quality of all arterial and venous regions was subjectively assessed. Results: In all patients who underwent multi-slice CT the pulmonary arteries as well as the veins of the lower half of the body could be recorded completely. Regarding the pulmonary arteries the image quality showed excellent results for the central and segmental arteries. The region up to the 3rd division in subsegmental branches could be sufficiently judged. More peripherally, a diagnostic assessment was not possible. The image quality of the veins was excellent in all sections, except the calf, where a reliable diagnosis could not be made. The comparison with the other techniques confirmed the superiority of multi-slice CT concerning the central and segmental pulmonary arteries and the veins from the popliteal vein to the inferior vena cava. In contrast, peripheral pulmonary emboli can be detected more certainly in ventilation/perfusion scans. The veins of the calf can be evaluated more reliably with venography. (orig.)

  17. Detection of malignant right coronary artery anomaly by multi-slice CT coronary angiography

    Coronary artery anomalies occur in 0.3-0.8% of the population and infer a high risk for sudden cardiac death in young adults. Diagnosis is usually established during coronary angiography, which is hampered by poor spatial visualization. Magnetic resonance imaging is an alternative, but it is not feasible in the presence of metal objects or claustrophobia. In this report, a 15-year-old boy experienced ventricular fibrillation and was successfully resuscitated. Cardiac catheterization was inconclusive, and pacemaker implantation prohibited the use of MR imaging. Multi-slice CT coronary angiography revealed a malignant anomalous right coronary artery. (orig.)

  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

    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...

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

    Elif Ergun; 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 ...

  20. The clinical application of multi-slice spiral CT angiography in abdominal aortic disease

    2005-01-01

    Objective: To evaluate the clinical application of multi-slice spiral CT angiography(MSCTA) in the assessment of abdominal aortic disease. Methods: Fifty-four patients underwent multi-slice spiral CT angiography of abdomen. Contrast agent (Omnipaque 300 I g/L) 1.5 ml/kg was injected and the injection rate was 3 ml/s. The delay time was determined by bolus tracking technique,Tll level abdominal aorta was set as the target vessel and the threshold was 180-200 Hu, slice width was 3 mm and with a pitch of 4-6.Original data were transferred to working-station to perform functional reconstruction. Results: Ten cases were normal, twenty-eight cases were abdominal aortic aneurysms, five abdominal aortic dissecting aneurysms (Debakay type Ⅲ ) and eleven aortic sclerosis. SSD showed the body of aneurysm and the relationship between aneurysm and adjacent blood vessel, MIP better displayed calcification of blood vessel wall and condition of the stent, MPR demonstrated true and false lumen, rupture site of abdominal aorta intima and mural thrombus. Conclusion: MSCTA axial and reconstruction image can show the extent of abdominal aortic disease and the relationship with adjacent blood vessels. It is a safe, simple and non-invasive examination method.

  1. The Correlation Between Age and Bleeding Volume in Haemorrhagic Stroke Using Multi Slice CT at District Hospitals in Jakarta.

    Saefudin, Tatan; Apriantoro, Nursama Heru; Hidayat, Ekaputra Syarif; Purnamawati, Schandra

    2016-04-01

    Haemorrhagic Stroke is a common disease in Indonesia. The best imaging modality for this disease is Multi Slice Computed Tomography Scanning (MSCT), as it may help strengthening the diagnosis as well as determining the brain bleeding volume. This study aimed to show correlation between bleeding volume of the brain and patient's age using cross-sectional approach. The 68 samples in this study were taken from secondary data from Head CT Scan of Haemorrhagic Stroke cases.  Brain bleeding volume is the dependent variable, obtained through slice thickness of 5 mm and ABC/2 method with software measurement in MSCT Scan device. The independent variable of this study is the patient's age. The result of the study was the average brain's bleeding volume of 21.76 ml ± 2.48 ml (range of 1.04 ml to 94.73 ml).The slice thickness using ABC/2 method, has a significant correlation with brain's bleeding volume in MSCT Scan examination, with correlation coefficient value r of 0.79. Brain bleeding volume in patients who have ages lower than 50 years and more or equal to 50 years were (18.93 ± 3.26) ml and (23.53 ± 3.47) ml respectively. There is no correlation between age and brain's bleeding volume in haemorrhagic stroke cases, with p value of 0.18, r = 0.19. PMID:26573030

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

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

    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.

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

    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.)

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

    Murphy, David J., E-mail: 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

  5. The application of the reduced dosage of the contrast medium with saline flush in cerebral and carotid angiography with 64-slice spiral CT

    Objective: To utilize the reduced contrast dose with saline flush in cerebral and carotid angiography with 64-slice spiral CT. Methods: According to the contrast dose, 40 patients undergoing cerebral and carotid CTA examination were randomly divided into 2 groups, one group was treated with 50 ml contrast agent and 20 ml saline flush, the other group was administrated with 70 ml contrast agent. With double blindness method, the data were respectively evaluated and analyzed by two radiologists independently. Results: For the two radiologists, on the manifestation of carotid and cerebral arteries, the venous artefact and the CT value measurement aspects, the Kappa value was respectively 0.895, 0.814, 0.702, 0.836. By rank sum test, on the manifestation of carotid arteries aspect, the grading score of the two groups of radiologist A was respectively 1.3, l.2; and that of radiologist B was respectively 1.4, 1.2; the differences between the two groups of the two radiologists have no statistical significance(U=173, P>0.05; U=128, P>0.05). And on the manifestation of cerebral arteries aspect, the grading score of the two groups of radiologist A was respectively 1.4, l.2; and that of radiologist B was respectively 1.2, 1.2; the differences between two groups of the two radiologists both have no statistical significance (U=160, P>0.05; U=106, P>0.05). And on the artefacts produced by the high contrast densities in the right subclavian vein, brachiocephalic vein and vena cava, the grading score of the two groups of radiologist A was respectively 1.3, 2.1; and that of radiologist B was respectively 1.2, 1.9; the differences between the two groups of the two radiologists both have statistical significance (U=75, P0.05). The CT value of the arteries of the two groups from radiologist B was respectively 337.3, 329.5, 239.2, 192.8, 345.6, 341.2, 247.1, 210.5 HU; and the difference between the two groups has no statistical significance (t=0.233, P>0.05). Conclusion: On the CTA

  6. Proximal arterioportal shunt in hepatocellular carcinoma: multi-slice spiral CT features and its clinical significance

    Objective: To evaluate the dynamic enhanced multi-slice spiral CT features and the formative mechanisms of proximal arterioportal shunt (APS) associated with hepatocellular carcinoma (HCC), and to assess the CT diagnostic ability and clinical value for proximal APS by comparing with digital subtraction angiography (DSA). Methods: One hundred and sixty-eight patients with HCC received both dynamic enhanced multi-slice spiral CT scan and DSA of the liver, and the time lapse between these two examinations was from 3 to 15 days. Of the 168 patients, 37 were massive tumors, 102 were nodular, and 29 were diffuse, respectively. Spiral CT signs and its diagnostic ability for proximal APS were analyzed and compared with the golden standard of DSA. Peripheral hepatic segmental or subsegmental small APS were excluded in our study. Results: Of the 168 patients with HCC, 42 (25.0%) were demonstrated to have proximal APS on DSA , and all the of 42 patients had positive CT findings related to proximal APS in arterial phase. Of the 6 patients proved to have false positive CT signs, 2 showed lower enhancement of portal vein (PV) than that of the aorta. The sensitivity, specificity, accuracy, and positive and negative predictive value of spiral CT in diagnosing proximal APS were 100.0%, 95.2 %, 96.4%, 87.5% and 100.0 %, respectively. There was a good correlation on the extent of APS to main PV, left or right PV, superior mesenteric vein, splenic vein, and coronary vein between CT and DSA in 35 patients (83.3%). The extent of APS to main PV and left or right PV was well correlated between CT and DSA in 38 patients (90.5%). The direct CT signs of proximal APS in arterial phase were revealed as early and strong enhancement of main PV and/or left or right PV approaching the density of the aorta (n=38). The indirect CT signs of proximal APS in arterial phase were demonstrated as high attenuation of normal hepatic parenchyma in the lobar distribution ipsilateral to the tumor (n=4

  7. Diagnostic value of multi-slice spiral CT angiography in visceral aneurysm

    Objective: To evaluate the diagnostic value of multi-slice spiral CT angiography (MSCTA) in visceral aneurysm. Methods: Unenhanced and contrast-enhanced CT scans in 42 cases of visceral aneurysm were retrospectively analyzed. volume rendering and multiplanar reconstruction were performed to reconstruct the vascular images. Results: The relationship between parent arteries and 58 aneurysms found in 42 patients were displayed clearly. The aneurysms arose from the splenic artery (27, 46.6%), hepatic artery (6, 17.2%), mesenteric artery (7, 12.1%), celiac artery (8, 13.8%). Three of the aneurysms were ruptured (5.2%) and 8 were associated with parent artery stenosis (13.8%). Conclusion: MSCTA clearly depict visceral aneurysm and complications. (authors)

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

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

    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.)

  9. 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

    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.

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

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

    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.)

  11. Multi-slice spiral CT angiography: clinical application and the evaluation

    Objective: To evaluate the clinical application of multi-slice spiral CT angiography (MSCTA) in diagnosis of vascular diseases. Methods: Imaging materials of multi-slice spiral CT angiography of 73 cases were retrospectively analyzed, including 27 cases of intracranial vascular CTA, 8 of carotid CTA, 10 of pulmonary artery CTA, 6 of coronary artery CTA, 11 of aortic CTA, and 11 of low extremity artery CTA. After the raw data was reconstructed by overlapping slice-chickness, the axial images were uploaded to workstation for post data processing, and were then evaluated and reconstructed using 3D software including maximum intensity projection (MIP), shaded surface display (SSD), and volume rendering technique (VRT). Results: The blood vessels were successfully demonstrated in 71 cases out of 73. Abnormality was found in 63 cases out of 71. The intracranial CTA showed aneurysm in 7 cases, arteriovenous malformation in 5, carotid-cavernous fistula in 2, cerebral vascular occlusion in 2, astrocytoma in 2, and meningioma in 3. The carotid CTA revealed carotid stenosis in 4 cases, vertebral artery stenosis in 2 and a post-bracket implantation subclavian artery. In pulmonary artery CTA, pulmonary artery embolism and 5 cases of pulmonary artery involved with lung cancer were seen in 3 cases. In coronary artery CTA, coronary artery stenosis were shown in 3 cases. The aortic CTA demonstrated aortic dissection in 4, aortic stenosis calcification in 5, aortic aneurysm in 2, liver cancer in 2, renal artery stenosis in 2, and Budd-Chiari syndrome in 2. CTA of low extremity artery revealed external iliac artery occlusion in 2 and femoral artery stenosis in 5. Conclusion: By combining axial images with various reconstructed with adjacent organs can also be evaluated. MSCTA is of convenience, reliability, safety and noninvasive. (authors)

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

    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)

  13. The study of the upper airway in obstructive sleep apnea hypopnea syndrome with multi-slice spiral CT

    Objective: To retrospectively investigate the upper airway (UA) characteristics of the obstructive sleep apnea hypopnea syndrome (OSAHS) with multi-slice spiral computed tomography (MSCT), and to analyze the value of MSCT in the clinical diagnosis and pathogeny research of OSAHS. Methods: The pharynxes of 28 cases with OSAHS and 14 controls were scanned by MSCT at the time of deep inspiration, deep expiration, normal respiration, and Mueller action. The cross-section area with its corresponding sagittal and transverse diameters at naso-, velo-, and tongue-pharyngeal level, the length and thickness of soft palate, the site and range of UA obstruction, and the pharyngeal collapsibility were measured and calculated, respective. Results: (1) MSCT with its software package could ideally and accurately help to observe the UA, measure the required data, and judge the range of UA obstruction. (2) Mean cross-section areas of velo-pharynx and tongue-pharynx in OSAHS were significantly less than those in the control group, which mostly occurred at the end of deep inspiration (P<0.05 ). (3) The collapsibilities at the velo-pharyngeal and tongue-pharyngeal levels in OSAHS were higher than those in the control group (F=15.133, P=0.001; F=5.552, P=0.025). (4) The soft palates of OSAHS were thicker than those in the controls (F=15.908, P=0.000). Conclusions: The straitness and the larger collapsibility at the velo-pharynx and tongue-pharynx are perhaps the main causes of OSAHS. MSCT is relatively convenient, quick, and accurate in the observation of the UA, thuspossessing the practical value in the clinical diagnosis and pathogeny research of OSAHS. (authors)

  14. 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

    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

  15. Non-invasive assessment of congenital pulmonary vein stenosis in children using cardiac-non-gated CT with 64-slice technology

    Background: Management of congenital pulmonary vein stenosis is a diagnostic challenge. Echocardiography may be insufficient and thus cardiac catheterization remains the reference standard in this setting. The aim of the study was to investigate the accuracy of cardiac-non-gated CT using 64-slice technology in detecting congenital pulmonary vein stenosis in children. Materials and methods: CT examinations were consecutively performed from May 2005 to December 2006 in 13 children aged 1.5-12 months (median 5 months) for suspected congenital pulmonary vein stenosis. Cardiac-non-gated CT acquisitions were performed after the peripheral injection of contrast agent. Pulmonary veins were evaluated for their pattern of connectivity from the lung to the left atrium and for the presence of stenosis. CT findings of pulmonary vein stenosis were compared with combined findings available from echocardiography, catheterization and surgery. Results: Pulmonary veins from the right lung (n = 29) and left lung (n = 26) were evaluated as separate structures (N = 55). Of the 55 structures, 32 had surgical and/or catheterization data and 45 had echocardiography for comparison. CT visualized 100% (55/55) of the investigated structures, while echocardiography visualized 82% (45/55). In the 13 subjects CT identified 10 stenotic pulmonary veins. CT confirmed the echocardiography suspicion of pulmonary vein stenosis in 100% (7/7) and established a new diagnosis in 3 other patients. CT agreed with surgery/catheterization in 100% (10/10) of the available comparisons. Conclusion: Cardiac-non-gated CT assessed the pulmonary veins more completely than echocardiography and should be considered as a viable alternative for invasive pulmonary venography for detecting pulmonary vein stenosis in children.

  16. Biological behavior and disease pattern of carcinoma gallbladder shown on 64-slice CT scanner: A hospital-based retrospective observational study and our experience

    AND Dwivedi

    2012-01-01

    Full Text Available Purpose: The aim of this diagnostic observational study was to assess the spread and biological behavior of gallbladder cancer using 64-slice computerized tomography (CT scanner in this particular geographic belt (eastern Uttar Pradesh, western Bihar, and northern Madhya Pradesh provinces of North India. Indians are ethnically and culturally different from their Western counterparts among whom the incidence of this disease is comparatively low. Subjects and Methods: After systemic examination, all patients (87 were subjected to ultrasonographic examination. All cases were histopathologically proven. Confirmed cases were subjected to volumetric CT examination of abdomen and pelvis, plain, post contrast and delayed phase. Results: Majority of the cases were adenocarcinoma. There was female preponderance with majority belonging to fifth and sixth decades. Commonest presentation was diffuse, irregular, enhancing wall thickening in 49.4%. Majority had invasion of liver parenchyma (74.7%. Cholelithiasis was seen in 48.3% cases. Invasion of biliary radicals was high (13.8-18.4%. Eleven cases had invasion of portal vein and tumor thrombus, with hepatic artery invasion in one case. In two cases, both hepatic artery and portal vein invasion was seen. Portal and peripancreatic nodal metastasis was seen in 58.5%. Distant metastasis was reported. Conclusion: Few studies involving the Indian population have attempted to use multi-row detector CT to define the biological behavior of carcinoma gallbladder. The opinion whether the pathology is operable or non-operable can reasonably be given. This large-scale, single-center study gives insight about the epidemiology and biological behavior of carcinoma gallbladder.

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

    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. Study of CdTe:Cl and CdZnTe detectors for medical multi-slices X-ray Computed Tomography; Etude de detecteurs en CdTe:Cl et CdZnTe pour la tomographie X medicale multicoupes

    Ricq, St

    1999-09-28

    The application of CdTe and CdZnTe detectors to medical X-ray Computed Tomography have been investigated. Different electrodes (Au, Pt, In) have been deposited on CdZnTe HPBM and on CdTe:ClTHM. Their injection properties have been determined with Current-Voltage characteristics. Under X-ray in CT conditions, injection currents measurements reveal trapped carriers space-charges formation. The same way, the comparisons of the responses to X-beam cut-off with various injection possibilities enable to follow the space-charges evolutions and then to determine the predominant traps types. Nevertheless, both hole and electron traps are responsible for the memory effect e.g. the currents levels dependence with irradiation history. This effect is noticed in particular on responses to fast flux variations that simulate scanner's conditions. Trap levels probably corresponding to native defects are responsible for these limitations. In order to make such detectors suitable for X-ray Computed Tomography, significant progresses in CdTe for CdZnTe crystal growth with an important defects densities reduction (factor 10), or possibly counting mode operation, seem necessary. (author)

  19. Value of multi-slice spiral CT MPVR reconstruction in the diagnosis of acute appendicitis

    Objective: To investigate the value of multi-slice spiral CT MPVR reconstruction in the diagnosis of acute appendicitis. Methods: A total of 39 patients with clinically suspected acute appendicitis underwent surgery from February, 2002 to September, 2003. They were prospectively examined before surgery with routine CT scanning and MPVR reconstruction spiral CT. 31 cases of appendicitis were confirmed after appendectomy. CT scans and surgery-pathology reports were evaluated on a five-grade scale from hyperemic-edematous appendix to abscess (normal appendix: 0 grade). Results: The results of spiral CT MPVR reconstruction were compared with the surgical and pathologic findings at appendectomy, yielding an accuracy of 87.2%, sensitivity of 90.3%, specificity of 75%, positive predictive value of 93.3%, and negative predictive value of 66.7%, respectively. Results of routine CT yielded an accuracy of 38.5%, sensitivity of 38.7%, specificity of 37.5%, positive predictive value of 70.6%, and negative predictive value of 13.6%, respectively. MPVR reconstruction signs of 28 patients with acute appendicitis included enlarged appendix ( > 6 mm) (96.4%), appendicoliths (26.7%), caecal apical thickening (36.7%), periappendiceal inflammation (71.4%), and abscess (10.7%). Conclusion: The use of spiral CT MPVR reconstruction in patients with equivocal clinical presentation suspected of having acute appendicitis can lead to a significant improvement in the preoperative diagnosis and maybe a decrease in surgical-pathologic severity of appendiceal disease. (authors)

  20. Multi-slice CT evaluation of glenoid bone loss in patients with recurrent anterior shoulder dislocation

    Objective: To evaluate multi-slice CT (MSCT) in glenoid bone loss of patients with recurrent anterior shoulder dislocation. Methods: MSCT findings of 108 patients with recurrent anterior shoulder dislocation and 12 with single anterior shoulder dislocation were retrospectively studied. The incidence, degrees and locations of glenoid bone losses were recorded. The incidence was analyzed with Fisher exact test. The maximum length,depth and proportion were compared with Wilcoxon rank sum test. Results: Glenoid bone loss was detected in 91.7% (99/108) patients with recurrent anterior shoulder dislocation. The proportion of glenoid bone loss was (16.0 ± 6.0)%, and the central locations of glenoid bone loss were from 2: 20 to 4: 25 (mean 3: 20). Sixty-two percent (67/108) patients had bony Bankart lesions in which 58.2% (39/67) bony fragments were free and 41.8% (28/67) were adherent to the anterior border of the glenoid cavity. Seventy-five percent (9/12) patients with single shoulder dislocation had anterior glenoid bone loss,and the proportion of glenoid bone loss was (15.2 ± 7.1)%. There were no statistical differences of the incidence (P=0.100) and proportion of glenoid bone loss (P=0.453) between the recurrent and single anterior shoulder dislocation. Conclusions: Anterior glenoid bone loss is common in patients with recurrent anterior shoulder dislocation. (authors)

  1. Value of MRI with sliding multi-slice technique for staging ovarian carcinoma

    Objective: To analyze the technical characteristics of sliding multi-slice magnetic resonance imaging (SMS-MRI), and to evaluate the value of staging ovarian carcinoma by SMS-MRI. Methods: Pre-operative SMS-MRI of chest, abdomen and pelvis was performed on 15 patients with ovarian carcinoma. Sequences included TSE T2WI, SMS TIRM and fat-suppressed contrast-enhanced SMS FLASH. The SMS-MRI was analyzed and staged according to FIGO's classification by two radiologists. The location of tumor, local invasion of uterus and fallopian tube or other pelvic tissues, peritoneum metastasis, lymph node metastasis and distal metastasis were recorded. The results were compared with operative and pathological findings. Results: The pathological diagnosis was serous cystadenocarcinoma (9), mucinous cystadenocarcinoma (2), endometrioid carcinoma (2), clear cell carcinoma (1) and granular cell carcinoma (1) at stage II (2), stage III (10) and stage IV (3). The accuracy of SMS-MRI staging was 100% (15/15). The tumor location, involvement of uterus and fallopian tubes as well as distant metastasis were accurately demonstrated by SMS-MRI. Conclusion: SMS-MRI can be a faster one-stop examination with good image quality. SMS-MRI is an alternative imaging method of staging ovarian carcinoma. (authors)

  2. Multi-slice spiral CT appearances of pulmonary infections after liver transplantation

    Objective: To investigate multi-slice spiral CT (MSCT) appearances of pulmonary infections after liver transplantation (LT) and the diagnostic values of MSCT. Methods: The clinical data and CT images of liver transplantation receptors were reviewed from 2001 August to 2007 June, the types, onset time and CT appearances of pulmonary infections were analyzed retrospectively. Chi square test was used for the statistics. Results: The incidence rate of pulmonary infections after LT was 32.9% (174/529), the mortality was 9.8% (17/174), The incidence of bacterial infection, fungus or associated fungus infection, and virus or associated virus infection were 17.2% (n=91), 14.7% (n=78)and 2.3% (n=12)respectively, the pulmonary infections were seen in 64.7%, 28.7% and 6.6% of patients 1 to 30 days, 31-90 days and after 90 days following LT. Consolidations (n=32), ground-glass opacities (n= 22), nodules (n=10), reticular or lineal opacities (n=4) were found in 45 patients who had CT examination, there were no statistic differences in incidence rate between bacterial infection and mycotic infection (P>0.05). Conclusion: Pulmonary bacterial and fungus infection are common after LT, and often present as the mixed infection, the high risk period for infection is within 30 days after LT, thoracic CT scan is very important for characterizing the pulmonary infections after LT. (authors)

  3. Multi-slice CT and MRI findings of the Listranc's ligament injuries

    Objective: To explore the multislice CT and MRI features of the Lisfranc's ligament injuries. Methods: In 23 cases of the tarsometatarsal joins injuries, 16 are men and 7 are women. The average age is 37 years(range 17-67 years). Ten cases are induced by the direct force and 13 cases are caused by the indirect force. All of the 23 cases were examined by the Siemens 64-slice CT scan, and then reformatted the tarsometatarsal joins with the MPR, CPR, SSD and VR. Ten of 23 cases were examined by oblique axial, sagittal and coronal view of the Siemens 1.5 T MRI. Results: On CT, the distance between the second metatarsus base and the medial cuneiform showed increase in 14 cases and the distance between the base of the second metatarsus and the first metatarsus was over 2 mm. In addition, the inside base of the second metatarsus and the lateral edge of the first cuneiform bone revealed fractures in 5 cases, respectively. The above CT characteristics may suggest the injuries of Lisfranc's ligament. Ten of the 14 cases were examined by MRI. The Lisfranc ligament was found to have injuries in these cases. The injuries were divided into 3 types: type I (Lisfranc ligament breaks) was 5 cases; type II (Lisfranc ligament shape is complete, but accompanied with avulsion fracture of the second metatarsal bone basis interior margin of attachment point of Lisfranc ligament) was 4 cases; and type III (Lisfranc ligament shape is complete, but accompanied with avulsion fracture of exterior margin of the inside cuneiform of attachment point of Lisfranc ligament) was 1 case. Conclusion: CT can demonstrate local soft tissue swelling, suggesting the Lisfranc ligament damage, and demonstrate clearly avulsion fracture of attachment point of Lisfranc ligament, but MRI can appraise accurately the Lisfranc ligament injuries. (authors)

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

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

    2013-07-15

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

  5. The comparative study between multi-slice spiral CT angiography and color flow ultrasonography in hepatic and splenic trauma

    Objective: To investigate the clinical value of multi-slice spiral CT angiography and color flow ultra- sonography in hepatic and splenic trauma. Methods Thirty-six cases of hepatic and splenic trauma were collected, the MSCT were analyzed and compared with that of color flow ultrasonography. Results: Seventeen cases were Hepatic trauma including nine cases of hepatic contusion, six cases of sub-envelope hematoma, two cases of both sub-envelope hematoma and hepatic contusion. Nineteen cases were splenic trauma including nine cases of splenic contusion, ten cases of sub-envelope hematoma. Conclusion: Multi-slice spiral CT angiography show hepatic and splenic trauma clearer than that of color flow ultrasonography, and can provide reliable basis for clinic diagnosis and therapy. (authors)

  6. The application of multi-slice CT and image post processing techniques in diagnosing of pulmonary embolism

    Objective: To characterize the pulmonary embolism (PE) on multi-slice CT pulmonary angiography, and to evaluate the role of multi-slice CT pulmonary angiography (CTPA) in the diagnosis of PE. Methods: Forty-five patients with PE confirmed by CTPA were retrospective analyzed. Images were reconstructed with maximal intensity projection (MIP), multiple planar reconstruction (MPR) and volume rendering technique (VRT). The display of pulmonary arteries and the ability of detecting embolisms were compared among the three different reconstruction techniques. Results: MPR images showed superiority to MIP and VRT images in displaying embolisms (P<0.05). Conclusion: MPR images were better than those of MIP and VRT, but provided poor three-dimensional information; MIP and VRT were more straightforward than MPR in displaying large branches of pulmonary artery. MPR combined with MIP and VRT could help to accurately establish PE diagnosis. (author)

  7. Enhancement of the low resolution image quality using randomly sampled data for multi-slice MR imaging

    Pang, Yong; Yu, Baiying; Zhang, Xiaoliang

    2014-01-01

    Low resolution images are often acquired in in vivo MR applications involving in large field-of-view (FOV) and high speed imaging, such as, whole-body MRI screening and functional MRI applications. In this work, we investigate a multi-slice imaging strategy for acquiring low resolution images by using compressed sensing (CS) MRI to enhance the image quality without increasing the acquisition time. In this strategy, low resolution images of all the slices are acquired using multiple-slice imag...

  8. Correction of misaligned slices in multi-slice cardiovascular magnetic resonance using slice-to-volume registration

    Hawkes David J; Schnabel Julia A; Netsch Thomas; Pinder Richard J; Chandler Adam G; Hill Derek LG; Razavi Reza

    2008-01-01

    Abstract A popular technique to reduce respiratory motion for cardiovascular magnetic resonance is to perform a multi-slice acquisition in which a patient holds their breath multiple times during the scan. The feasibility of rigid slice-to-volume registration to correct for misalignments of slice stacks in such images due to differing breath-hold positions is explored. Experimental results indicate that slice-to-volume registration can compensate for the typical misalignments expected. Correc...

  9. Multi-slice spiral CT perfusion imaging of chronic obstructive pulmonary disease

    Objective: To evaluate the diagnostic value of multi-slice spiral CT (MSCT) perfusion imaging in chronic obstructive pulmonary disease (COPD). Methods: Twenty COPD patients and 20 volunteers underwent 8-row detector spiral CT (MSCT) perfusion imaging using cine scan mode with 5 mm slice thickness, 0.5 s rotation time and a total scan time of 45 s with 5 s intervals. 60 ml contrast agent (300 nag I/ml) were administered at a rate of 4 ml/s from the forearm superficial vein. The imaging data were transferred to a workstation. A time-density curve and pseudo-color map were generated automatically with GE CT perfusion 3 software, the blood flow (BF), blood volume (BV), mean transit time (MTT) and permeability surface (PS) were measured. Results: Time-density curve was flatter and the peak of the curve was obviously lower in COPD patients than the volunteers. The BF, BV, PS in COPD patients was (24.77±11.49) ml·min-1·100 g-1, (2.48±1.02) ml/100 g and (2.75±1.13) ml· min-1·100 g-1 respectively. In volunteers was (290.14±107.59) ml·min-1·100 g-1, (16.51 ± 5.98) ml/100 g, (8.80±3.03) ml·min-1·100 g-1 respectively. The MTT in COPD patients and volunteers was (10.58±4.85) s and (4.50±1.71)s respectively. The BF, BV and PS in COPD patients was lower than the volunteers, the MTY was higher (P<0.01). Conclusion: MSCT perfusion imaging is helpful for the diagnosis of COPD. (authors)

  10. Multi-slice CT-colonography in low-dose technique - preliminary results

    Purpose: Assessment of multi-slice CT-colonography (MSCTC) with standard and low-dose technique in comparison to conventional colonoscopy (CC). Materials and Methods: After standardized bowel cleansing, 28 men and 24 women (mean age 60,3 years) underwent CC within two hours after MSCTC had been performed (4 x 2.5 mm collimation, 3 mm slice width, 17.5 mm table feed, 120 kVp). In 19 patients, MSCTC was performed with 120 mAs (CTDIw,eff: 11.28 mGy), and in 33 patients with 10 mAs (CTDIw,eff: 0.94 mGy), respectively. After noise reduction using mathematical algorithms by a dedicated software (ECCET), images were analyzed by two blinded readers in simultaneously displayed 2D- and 3D-modes. Findings in MSCTC were compared to the results obtained with CC. Results: Calculated effective doses ranged between 9 and 12 mSv for 120 mAs, and between 0.75 and 1 mSv for the low-dose technique. In standard dose MSCTC, 20 of 25 lesions (80%) were found: all 7 tumors (100%), one large polyp (> 10 mm; 100%), 6 of 7 medium sized polyps (9.9 to 5 mm; 86%) and 6 of 10 small polyps (< 5 mm; 60%). In low-dose MSCTC, 32 of 44 lesions (73%) were seen: all three large polyps (100%), 13 of 14 medium sized polyps (93%) and 16 of 27 small polyps (59%). An overall sensitivity of 78% with a specificity of 68% was calculated. False positive findings were seen mostly for small lesions (12 for standard dose, 11 for low-dose). Conclusion: Despite a 12-fold reduction of radiation exposure, MSCTC in low-dose technique performs comparably well to standard dose MSCTC. After mathematical noise reduction, more than 90% of polyps larger than 5 mm can be detected. (orig.)

  11. Multi-slice CT for visualization of pulmonary embolism using perfusion weighted color maps

    Purpose: The purpose of our preliminary study was to evaluate the feasibility of a new technique for the perfusion weighted color display of the density of lung parenchyma derived from multi-slice CT (MSCT) data sets of clinical routine examinations for visualization of pulmonary embolism (PE). Materials and Methods: Imaging of patients with suspected PE was performed on a commercially available MSCT (Somatom Volume Zoom; Siemens, Forchheim, Germany) after intravenous application of 120 cc of contrast-medium using a power injector. Scan parameters were 140 kV and 100 mAs, using a thin collimation of 4x1 mm and a table speed of 7 mm (pitch: 1.75). Derived from thin collimation axial slices (slice thicknesseff. 1.25 mm, reconstruction increment 0.8 mm), a new image processing technique was deployed. Based on these source images, an automated 3D-segmentation of the lungs was performed followed by threshold based extraction of major airways and vascular structures. The filtered volume data were color encordes and finally overlayed onto the original CT images. This color encoded display of parenchymal density distribution of the lungs was shown in axial, coronal and sagittal plans orientation. In four patients with excluded PE as well as in two patients with proven PE this new technique was performed. Results: In the four patients that were considered negative regarding PE on MSCT, lung densitometry showed a homogeneous distribution of color encoded densities without circumscribed decreased or increased areas, beside the usually present gravity-dependent gradient in ventro-dorsal direction. In the two patients with proven PE, low density values on perfusion weighted color maps were found distally to the occluded pulmonary arteries. (orig.)

  12. The comparison of imaging quality between bolus-triggering and test-bolus technique used in 64-slice spiral CT angiography of lower extremity arteries

    Objective: To investigate the clinical value of multi-slice CT angiography (MSCTA) of lower limbs in patients with peripheral arterial occlusive disease (PAOD) using the test-bolus technique. Methods: Forty-four patients with PAOD were enrolled consecutively in the study. In group 1, 18 subjects underwent CTA by bolus triggering method and in group 2, 26 subjects underwent CTA by test-bolus technique. During scanning procedure in group 2 subjects, the bolus transit time to aorta (TAO), popliteal arteries (TPOP) and aorto-popliteal bolus transit time (Tt) were calculated through dynamic acquisition at their respective level and the delay time were immediately set as TAO and scan time as double Tt. Two independent senior attending physicians with training experience in interpreting CTA determined the quality of each arterial segment visualization based on 5 parameters (1. visible farthest branch, 2. clarity of vessels border, 3. presence of venous contamination, 4. grading of stenosis, 5. CT value at 4 arterial segments). Inter-observer agreement on imaging quality between readers was evaluated using Cohen's k statistic by calculating K values. χ2 test and t test were used to compare the quality of images in both groups. Results: In group 2 patients, a larger individual variation in transit time of the contrast to reach aorta was obserued [TAO=(17.1±2.6) s with a range of 12.0-22.0 s] and aorto-popliteal transit time [Tt=(14.8±5.5) s with a range of 8.0-24.0 s]. CTA of group 2 patients demonstrated better quality over group 1 patients' CTA, especifically in the infra-popliteal and foot area arteries. There was an excellent inter-observer agreement for group 2 patients (K>0.80) whereas in group 1 agreement in infra-popliteal segments for venous contamination (K value 0.60) and stenosis degree (K value 0.50) were not satisfactory enough. Group 1 patients were reported to have more severe stenosis in infra-popliteal and foot arteries (χ2=30.55 and 22.41, P<0

  13. Multi-slice spiral CT of aortocoronary grafts and internal mammary artery bypasses: Assessment of bypasses and their anastomoses; Mehrzeilen-Spiral-CT von aortokoronaren Venenbypaessen und Mammaria-interna-Bypaessen: Beurteilung der Bypaesse und ihrer Anastomosen

    Froehner, S.; Wagner, M.; Schmitt, R.; Christopoulos, G.; Coblenz, G. [Inst. fuer Diagnostische und Interventionelle Radiologie, Herz- und Gefaessklinik GmbH, Bad Neustadt an der Saale (Germany); Brunn, J.; Mueller, M.; Kerber, S. [Fachbereich Kardiologie, Herz- und Gefaessklinik GmbH, Bad Neustadt an der Saale (Germany); Urbanski, P. [Klinik fuer Herzchirurgie, Herz- und Gefaessklinik GmbH, Bad Neustadt an der Saale (Germany)

    2002-07-01

    Objective: To assess aortocoronary grafts and internal mammary artery bypasses by means of EKG-triggered contrast-enhanced multi-slice spiral CT, and to evaluate the diagnostic accuracy of this new imaging modality. Material and methods: 59 patients with up to 5 aortocoronary grafts and/or internal mammary artery bypasses per patient were examined with regard to bypass morphology, the free passage, and the proximal as well as the distal anastomoses using multi-slice computed tomography. Axial source images were calculated by means of retrospective triggering at different diastolic delay times, and were postprocessed in several planes with the multiplanar volume reconstruction (MPVR) software. Results: On the pre-condition that data sets were acquired at sinus rhythm and at a heart rate lower than 65/min, aortocoronary grafts and internal mammary artery bypasses could be depicted in adequate diagnostic quality in about 80% of all cases with contrast-enhanced multi-slice spiral CT. Both, the free passage of the bypasses as well as the morphology of the proximal anastomoses were sufficiently assessed with multiplanar volume reconstruction (MPVR), whereas the distal anastomoses couldn't be depicted sufficiently in 20% of all cases. Conclusion: As a non-invasive method, contrast-enhanced and ECG-triggered multi-slice spiral computed tomography has gained diagnostic potential for the accurate visualization of aortocoronary grafts and the internal mammary artery bypasses. (orig.) [German] Ziel: Die vorliegende Arbeit stellt die Moeglichkeiten der kontrastmittelverstaerkten, EKG-getriggerten Mehrzeilen-Computertomographie in der Beurteilung von aortokoronaren Venenbypaessen und Mammaria-interna-Bypaessen dar. Material und Methode: Bei 59 Patienten mit 1 bis 5 aortokoronaren Venen-Bypaessen bzw. Mammaria-interna-Bypaessen wurden deren Morphologie, Durchgaengigkeit, die proximalen Anastomosen und die distalen Insertionsstellen mittels Mehrzeilen-Spiral-CT untersucht

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

    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...

  15. Analysis about Inlfuencing Factors of Image Quality of Coronary Angiography with Multi-Slice CT%MSCT冠状动脉成像质量的影响因素分析

    赵坤; 邵广瑞; 王勇; 侯代伦

    2014-01-01

    目的:分析64层螺旋CT冠状动脉扫描中影响成像质量的各种因素。方法对89例怀疑冠心病或冠心病复查患者进行64层螺旋CT冠状动脉检查,回顾性分析成像质量,探讨心率及心率波动对冠脉成像质量的影响,pitch值与心率的关系,替代(override)功能的应用价值,从而优化扫描参数。结果心率及心率波动与冠脉成像质量成负相关;心率与扫描/重建方式及pitch值存在相互对应关系;心率替代功能的合理使用可以提高CT冠状动脉的成像质量。结论通过控制心率及心率波动,选择心率替代功能,采取适当的扇区扫描/重建模式可以提高图像质量和冠状动脉诊断的可靠性。%Objective To analyze the inlfuencing factors of image quality of coronary angiography with 64-slice CT.Methods Eighty-nine patients with known or suspected CAD underwent CT coronary angiography using 64 multi-slice CT. The image quality in those cases was analyzed retrospectively to evaluate the influence of heart rate, fluctuation of heart rate during the scanning. The relationship between heart rate and the value of pitch was analyzed, and the application value of the override function was discussed.Results① The patient’s heart rate and lfuctuation were negatively related to the coronary image quality.② There was corresponding relationship between the value of pitch and segment scan/reconstruction mode according to the heart rate.③ Correct use of override function could improve the image quality of coronary.Conclusion The appropriate control of heart rate and lfuctuation, the correct use of override function, and the corresponding selection of segment scan/reconstruction mode according to the heart rate could improve the image quality and reliability of coronary angiography.

  16. Application of low dose multi-slice helical CT in orbital trauma patients

    Objective: To investigate the most appropriate low radiation dose in multi-slice CT (MSCT) scans for orbital trauma patients. Methods: Thirty trauma patients with suspected orbital fractures who underwent helical CT scans with a 64-MSCT using regular dose were selected. Noise was artificially introduced to the axial images using an image space noise addition tool to simulate 6 sets of lower dose scans with tube current of 30, 70, 100, 140, 170 and 200 mA, respectively. The lowest tube current with adequate image quality for confident diagnosis was determined based on the evaluation of the overall image quality and fracture detection on images at different dose levels. The determined lowest tube current was then validated using clinical scans. Radiation dose related parameters CTDIvol, DLP, ED were also recorded. Image quality was evaluated according to its low-density resolution, noise and structure clarity and characterized into 5-grades of excellent, good, fair, worse and worst. Rank sum test and χ2 test were used for statistics. Results: In 30 trauma patients with regular dose of 300 mA, there were 30 cases of orbital fracture, 19 cases of intraorbital emphysema, 12 cases of ocular muscle injury and 1 case of intraorbital foreign body. These changes could still be clearly observed and correctly diagnosed when the tube current was reduced to as low as 70 mA. However, the overall image quality was mostly fair. At the simulated dose of 100 mA, the majority of images were characterized as excellent or good, and there was no statistical difference compared with that of regular dose scans (P>0.05). In the clinical evaluation for 20 orbital trauma patients with the reduced tube current of 100 mA, the majority of images were judged to be excellent (9 cases) or good (17 cases) and fair (4 cases). The radiation dose (0.29 mSv) was reduced by 70% compared with that of regular tube current of 300 mA (0.86 mSv). Conclusion: The tube current of MSCT may be used as low as 100

  17. The value of multi-slice spiral CT in the preoperative assessment of living renal donor

    Objective: The purpose of this study is to assess the value of multi-slice spiral CT (MSCT) in the preoperative evaluation of living renal donor as a all in one modality. Methods: Thirty-six potential living renal donors underwent the examination using a GE light VCT scanner. Informed consent was obtained from all participants. The plain scan, early arterial phase, late arterial phase and excretory phase scans are performed in the former 25 donors (injection rate 5 rolls, total volume 100 mi, tube tension 120 kV). While in the later 11 donors (2 ml/s 40 ml +4 ml/s 60 ml), the scanning protocol included the plain scan ( 100 kV), vascular phase and excretory phase scans (100 kV). The excretory phase data were used in the reconstruction of CT urography in both groups. All images were reviewed by one radiologist and one urologist, and the findings of MSCT were compared with intraoperative findings for 33 donors, to investigate the utilities of MSCT in assessing renal vascularity, urinary tract and lesions of renal parenchyma. When discrepancies are found between the two reviewers, consensus was obtained via discussion. Au data was statiscally processed with SPSS for Windows. Results: MSCT angiography is in accordance with intraoperative findings in demonstrating the anatomy of renal arteries and renal vein trunk, accesary arteries, early branching of renal artery. The findings from CTA are highly in accordance with the intraoperative findings, which facilitate intraoperative ligation and reduce relevant complications. CTU demonstrates the anatomy of urinary, tract in good agreement with the intraoperative findings. The image quality of 3D vascularity and CTU between the two groups, scored 4.4 ± 1.2 vs 4.2 ± 1.3 and 4.6 ± 0.8 vs 4.4 ± 0.9 respectively, no statistical between-groups difference was found (Z=-0.89, -0.47, P>0.05). Conclusion: MSCT multiphase scanning combined with CTA and CTU play a important role in the evaluation of living renal donor, which

  18. 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

    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.)

  19. 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

    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.)

  20. Multi-slice echo-planar spectroscopic MR imaging provides both global and local metabolite measures in multiple sclerosis

    Mathiesen, Henrik Kahr; Tscherning, Thomas; Sorensen, Per Soelberg;

    2005-01-01

    MR spectroscopy (MRS) provides information about neuronal loss or dysfunction by measuring decreases in N-acetyl aspartate (NAA), a metabolite widely believed to be a marker of neuronal viability. In multiple sclerosis (MS), whole-brain NAA (WBNAA) has been suggested as a marker of disease...... longitudinal studies have often been hampered by standardization and reproducibility problems. Multi-slice echo-planar spectroscopic imaging (EPSI) is presented as a promising alternative to single-voxel or nonlocalized spectroscopy for obtaining global metabolite estimates in MS. In the same session...

  1. Clinical application of multi-slice helical CT volumetric scanning in lumber spine

    Objective: To evaluate the clinical application value of multi-slice helical CT volumetric (VH) scanning in lumber spine. Methods: One thousand of patients with back and leg pain who underwent CT examinations were selected as subjects. We simulated the traditional protocol of single-slice(SS) discrete scanning for L3/4, L4/5, and L5/S1 intervertebral discs. The VH scanning mode was performed with 120 kV, 210 mAs, pitch of 1.5 and coverage of 97.5 mm. The simulated SS scanning mode was performed with 120 kV, 240 mAs and coverage of 45.0 mm. The diagnostic outcomes and the radiation doses were compared between the two scanning modes. Two groups doctors observed ten terms, including the osseous spinal stenosis, narrowed intervertebral space and so on in two scanning modes respectively. Then consistency analysis of the data was carded out. Results: The VH scanning mode showed far more features than the SS mode. The detection rates of the VH mode in the osseous spinal stenosis, narrowed intervertebral space, herniated nucleus pulposus, narrowed lateral recess, vertebral lesion, hypertrophy of L5 transverse process, abnormal direction of facet, facet degeneration, lumbar spondyloschisis, and paraspinal soft tissue were 11.8% (n=118), 38.5% (n=385), 9.3% (n=93), 46.8% (n=468), 31.4% (n=314), 5.7% (n= 57), 25.4% (n=254), 49.7% (n=497), 9.9% (n=99), and 0.6% (n=6) respectively, while the detection rates of the SS mode in ten terms were 5.6% (n=56), 0, 0.6% (n=6), 27.9% (n=279), 22.4% (n=224), 1.2% (n=12), 16.7% (n=167), 37.2% (n=372), 0.5% (n=5), and 0.2% (n=2) respectively. The difference between the two groups had statistically significance (average P0.05). The detection rates of the VH mode were higher than the SS mode in the osseous spinal stenosis, narrowed intervertebral space, herniated nucleus pulposus, lumbar spondyloschisis, being 6.2% (n=62), 38.5% (n=385), 8.7% (n=87), and 9.4% (n=94), respectively. In addition, VH mode only partially showed the articular facets

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

    Elif Ergun

    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.

  3. 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

    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

  4. Assessment of Left Ventricular Volumes and Function: Intra individual Comparison of Multi-slice Spiral CT and Electron Beam CT in an Animal Model

    Purpose: To evaluate multi-slice spiral computed tomography (MSCT) for measurements of left ventricular volumes, ejection fraction (EF), and myocardial mass in comparison with electron beam CT (EBCT) as a reference method. Material and Methods: Six minipigs underwent both standardized contrast-enhanced MSCT (effective acquisition time per cardiac cycle 125.7±30.1 ms, reconstructed slice thickness 8 mm) and EBCT (acquisition time 50 ms, collimated slice thickness 8 mm). The contrast-to-noise ratio of the left ventricle was measured in each animal, and the contour sharpness of the myocardium was analyzed. Volumes (EDV, ESV, SV) ejection fraction (EF), and muscle mass were calculated by MSCT and by EBCT using the slice summation method. Results: MSCT had a higher contrast-to-noise ratio and delineated the myocardial contours more sharply than EBCT. There was a close linear correlation between both modalities for all parameters (EDV: r P =0.88, ESV: r P =0.91, SV: r P =0.85, EF: r P =0.93; mass: r P =0.90; P <0.05 each). MSCT slightly overestimated ESV and slightly underestimated SV and EF compared with EBCT ( P <0.05 each). Conclusions: Image quality in MSCT is superior to that of EBCT. Functional parameters correlate well between both modalities, but the accuracy of MSCT is limited by its lower temporal resolution

  5. Long-term follow-up of surgically excluded popliteal artery aneurysms with multi-slice CT angiography and Doppler ultrasound

    The purpose of this study was to evaluate the role of multi-slice computed tomography (MSCT) angiography in the follow-up of popliteal artery aneurysms (PAAs) that have been operated on. Aneurysm exclusion and progression, graft patency and graft-related complications were analyzed. Fourteen patients with 21 surgically excluded PAAs were evaluated with MSCT angiography with slice thickness of 1.25 mm. The mean follow-up time was 67 months. MSCT demonstrated blood flow in six non-excluded PAAs (24%), with an average increase in the diameter of 21 mm over time. Fifteen PAAs demonstrated no blood flow and revealed an average decrease of 7 mm in diameter. The origin of this residual perfusion was demonstrated, and collaterals were involved in five of six non-excluded PAAs. In addition, MSCT demonstrated three graft stenoses. Furthermore, two occluded grafts were visualized. Twenty-four percent of the patients after surgical exclusion of PAAs revealed residual perfusion within the aneurysmal sac during follow-up, with a significant increase in the aneurysmal size with MSCT. Moreover, evaluation of the graft patency could also be done as could demonstration of anastomotic abnormalities. Thus, MSCT might be considered as a new tool to evaluate residual collateral feeding of popliteal aneurysmal sac and could be useful in identification and localization of feeding vessels. (orig.)

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

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

    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

  7. Studies on intracranial collateral circulation with multi-slice CT angiography in patients with symptomatic cerebral artery stenosis

    Shu-qing ZHOU

    2011-06-01

    Full Text Available Objective To explore the features of intracranial collateral circulation in patients with symptomatic cerebral artery stenosis.Method Ninety-four patients with ischemic cerebrovascular disease admitted from Apr.2004 to Jun.2009 were involved in present study.All the patients were examined with cerebral multi-slice CT angiography,and the features of cerebral artery stenosis and intracranial collateral circulation were evaluated using maximum intensity projection(MIP and volume rendering(VR images of CT angiography.Result Of the 94 patients involved,48 were diagnosed as cerebral artery stenosis,including 29 cases of cerebral infarction,18 of transient ischemic attack(TIA and 1 of moyamoya disease(MMD.Among the 14 cases of severe cerebral artery stenosis or occlusion,cerebral infarction was found in 6 cases with lesser intracranial collateral vessels(including massive cerebral infarction in 4 cases and watershed infarction in 2 cases,and focal infarction of central semi-ovale in 1 case and TIA in 7 cases were found with abundant intracranial collateral vessels.Multiple lacunar infarction was found in 22 cases of mild or moderate cerebral artery stenosis,but there was no significant correlation between the stenosed arteries and infarction sites.Abundant intracranial collateral vessels were found in one patient with Moyamoya disease but no infarction was observed.Conclusions Intracranial collateral circulation plays an important role of compensation in patients with severe cerebral artery stenosis or occlusion.Cerebral angiography with multi-slice CT is of great significance in evaluation of cerebral artery stenosis and intracranial collateral circulation.

  8. Impact of image noise levels, scout scan dose and lens shield on image quality and radiation exposure in z-axis dose-modulated neck MSCT on 16- and 64-slice Toshiba Aquilion scanners

    Objective: Assessing the impact of image noise (IN) levels, scout scan dose and lens shield use on image quality and radiation exposure in neck multislice CT (MSCT) when using z-axis dose modulation (DM). Methods: Neck MSCT phantom studies with/without z-axis DM were performed by using different IN levels (S.D. 7.5-30 HU) and scout scan tube currents (7.5-50 mA) on Toshiba Aquilion scanners (16-/64-slice). Image quality indices were evaluated by two radiologists and radiation exposure parameters calculated. Cadaveric phantom measurements elucidated lens shield interactions with DM efficacy. The lowest dose scan protocol with diagnostic image quality was introduced into the clinical imaging routine and retrospectively evaluated in 20 age-matched patients undergoing neck MSCT with/without DM. Results: The highest image noise level in DM neck studies with comparable image quality to standard neck CT amounted to 20 HU, resulting in a mean tube current of 50 mAs (CTDIw 6.3 mGy). DM reduced effective dose by 35% and organ dose figures (lens, thyroid) by 33%. Scout scan dose lowering to 20 mA resulted in an effective dose (ED) decrease of 0.06 mSv (5%). Avoiding lens shield placement during scout scan effected an organ dose decrease of 20%. Overall contour sharpness and image contrast did not differ significantly (DM/without DM) whereas image noise was rated higher in DM neck CT studies (p < 0.05). Conclusions: z-Axis dose modulation, as assessed on 16- and 64-slice Toshiba Aquilion scanners, is effective and mandatory in neck MSCT. DM efficacy can be enhanced by optimising scout scan doses and lens shield use.

  9. Role of multi-slice CT coronary angiography in evaluating the different patterns of coronary artery disease in patients with unstable angina

    Gamal Eldine M. Niazi

    2015-09-01

    Conclusion: Non-invasive multi-slice CT coronary angiography is a reliable technique of high ability to detect coronary artery disease and estimate the degree of obstruction, number of affected arteries and the pattern of their affection and can be used in workup in patients with unstable angina.

  10. Comparison of multi-slice spiral CT versus 3.0 T MR imaging in assessing tumor regression after radiofrequency ablation of hepatocellular carcinomas

    Objective: To assess the diagnostic value of MR imaging in follow-up evaluation of patients with hepatocellular carcinomas (HCC) treated with radiofrequency ablation (RFA) and to compare it with that of multi-slice CT. Methods: From December 2009 to September 2011, there were 48 patients (56 HCCs) treated with RFA after transcatheter arterial chemoembolization (TACE). MR imaging and multi-slice CT were performed for follow-up. Two radiologists independently reviewed these images, detection of residual or recurrent tumor were assessed on a five-point scale and compared with Kappa test and with the method of receiver operating characteristic (ROC) curve analysis. Sensitivity, specificity and accuracy were evaluated. Results: The observer agreement rate for MR imaging was higher (0.925) than for multi-slice CT (0.701, P<0.05). The area under the ROC curve (AUC) of MR imaging (0.987 and 0.971 by two radiologists respectively) was significantly higher than that of CT (0.674 and 0.598 by two radiologists respectively), P<0.05. The sensitivity, specificity and accuracy of detection rate for MRI [100%(22/22), 95.5% (86/90) and 95.5% (107/112), respectively] were significantly different with that for multi-slice CT [40.9% (9/22), 57.8% (52/90) and 60.7% (68/112), respectively]. Conclusion: Diagnostic accuracy and detection rate of residual or recurrent tumor were found to be superior with MR imaging than with multi-slice CT. (authors)

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

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

    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

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

    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 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.)

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

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

    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.)

  14. 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

    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

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

    韩璐璐; 张锡海; 张爱霞; 王俊英; 董乐

    2015-01-01

    目的:为了进一步提高临床对自发性蛛网膜下腔出血(SAH)的治疗效果,分析和探讨64层螺旋 CT血管成像在自发性 SAH 中的应用价值。方法按照随机双盲的原则抽取2014年1月-2015年1月治疗的38例考虑自发性 SAH 的患者作为研究对象,所有入组的患者均常规给予64层螺旋 CT 血管成像(CTA)及数字减影脑血管造影(DSA)检查,其中 CT 血管成像均应用最大密度投影(MIP)、容积再现技术(VR),通过和 DSA 结果对比分析 CTA 在发现自发性 SAH 中的病因诊断中的应用价值和意义。结果以 DSA 诊断结果作为评价标准,CTA 的诊断结果准确率和 DSA 相比较,差异亦无统计学意义(P ﹥0.05);而 CTA 组在诊断血管瘤大小方面和 DSA 诊断结果准确率和 DSA相比较示,差异无统计学意义(P ﹥0.05)。结论临床上在诊断自发性 SAH 的过程中应用64层螺旋 CT 血管成像,不仅简单、快捷和方便,而且有利于发现病因和提高诊断准确率,值得推广。%Objective To further improve the effectiveness of our hospital in terms of t spontaneous subarachnoid hemorrhage(SAH)and to reduce and prevent the occurrence probability of a variety of adverse events,analysis and discussion of the meaning and value of 64-slice CT angiography(CTA). Methods Selected 38 cases of patients with spontaneous sub-arachnoid hemorrhage(SAH)in our hospital from January 2014 to January 2015 according to the randomized double blind controlled principles as a study object,all patients with acute SAH underwent 64-slice CTA and digital subtraction angiography (DSA). Three-dimensional post-processing techniques including volume rendering( VR),maximum intensity projection (MIP),curved planar reformation(CPR)and multi-planar reconstruction(MPR)were underwent. Results Taking the DSA result as the standard,CTA diagnosis accuracy compared with DSA the difference between the two groups weren

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

    迟宝权; 刘亚静; 康洁

    2011-01-01

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

  17. 64排螺旋CT在泌尿系三维成像检查中的影响%Effects of 64 slice spiral CT 3D imaging in urinary system

    王强

    2013-01-01

    Objective To investigate the clinical value of 3D imaging exams after 64-slice spiral CT scan.Methods Conventional thin plain scan and arterial phase,venous phase,delayed phase scans to 50 patients with urinary tract diseases were performed respectively by applicating 64-slice spiral CT,then,the data were transferred to the imaging workstation for MPR,VR and MIP and other 3D reconstruction,ifnally,a comprehensive analysis was made to all image data.Results kidney or ureteral stones in 33 cases,occupying of kidney,ureter or bladder in 8 cases,inflammation in 6 cases,congenital malformations in 2 cases,ureteral clot in 1 case.Conclusion 3D imaging exams after 64-slice spiral CT scan has a reliable value to the diagnosis of urinary tract disease,it can not only get a clear kidneys,ureter and bladder dimensional reconstructed images,but also accurately display the urological global and local ifne structure,shape,extending direction and its relationship with the surrounding tissue.In addition,the image can be made rotation,cutting,ampliifcation and other post-processing.%目的:探讨64排螺旋CT在泌尿系三维成像检查中的临床应用价值。方法抽取来我院就诊的泌尿系疾病患者50例,应用64排螺旋CT分别行常规薄层平扫及动脉期、静脉期、延迟期扫描,并将所得数据传输至影像工作站进行MPR、VR及MIP等三维重建,对其影像资料进行综合分析。结果肾或输尿管结石33例,肾、输尿管或膀胱占位8例,炎症6例,先天性畸形2例,输尿管内血块1例。结论64排螺旋CT三维成像检查不仅能够获得清晰的双肾、输尿管及膀胱的三维重建图像,而且能够准确地显示出泌尿系统整体和局部的细微结构、形状、走形及其与周围组织关系,还可对图像进行旋转、切割、放大等后处理操作,对于临床诊断泌尿系统疾病具有可靠价值。

  18. 64排CT血管造影在动脉瘤性蛛网膜下腔出血的临床研究%Clinical research of 64-slice CT angiography in aneurysmal subarachnoid hemorrhage

    陈立朝; 许民辉; 邹咏文; 杨东虹; 张云东; 徐伦山; 张溢华

    2011-01-01

    目的:评估CT血管造影(CTA)在动脉瘤性蛛网膜下腔出血(SAH)病人中选择治疗策略的作用.方法:对231例动脉瘤性SAH病人行64排CTA检查.选择临床治疗方案,并通过DSA或外科手术验证CTA检查的准确性.结果:CTA检查与DSA或术中探查一致228例,CTA信息不充分2例,CTA漏诊1例;CTA检查的敏感性98.7%,特异性100%.根据CTA检查确定治疗方案228例(98.7%),其中采用血管内栓塞治疗141例,夹闭术87例;根据DSA检查,采用血管内栓塞治疗3例.结论:64排CTA能准确检测颅内动脉瘤及其特征,有助于选择治疗策略.%Objective To evaluate the clinical application of CT angiography (CTA) in making therapeutic strategy for patients with aneurysmal subarachnoid hemorrhage (SAH). Methods The 64-slice CTA examination was performed in 231 patients with aneurysmal SAH to select appropriate treatment strategies. CTA findings should be confirmed by DSA or surgical exploration. Results CTA findings were coincident with the findings by DSA or surgical exploration in 228 cases, CTA findings were insufficient in 2 cases, and missed diagnosis by CTA in 1 case. The sensitivity of CTA examination was 98.7% and specificity was 100%. The therapeutic measures were decided based on CTA in 228 cases (98.7%), including endovascular treatment in 141 cases, clipping of aneurysm in 87. Endovascular treatment was adopted based on DSA in 3 cases. Conclusions The 64-slice CTA as an accurate tool for detecting intracranial aneurysms is useful to decide therapeutic strategy.

  19. A study on the application of CT perfusion and CT angiography with 64-slice spiral CT in the evaluation of internal carotid artery and middle cerebral artery stenosis and occlusion

    Objective: To evaluate clinical application of combined cerebral CT perfusion (CTP) with head and neck CT angiography (CTA) using 64-slice spiral CT on the cerebral ischemia caused by the stenosis or occlusion of internal carotid artery (ICA) and middle cerebral artery (MCA). Methods: The sixty nine patients with unilateral or bilateral ICA and MCA stenosis or occlusion confirmed by digital subtraction angiography underwent head plain CT scan, cerebral CTP, and head and neck CTA using 64-slice spiral CT. Ten normal adults served as control. To discriminate the ischemic foci, the parameter maps of cerebral blood flow (CBF), cerebral blood volume (CBV), mean transit time (MTF) and time to peak (TTP) were obtained. Results: Among the patients with unilateral ICA stenosis or occlusion diagnosed by CTA, abnormal perfusion was found only in the watershed zone in 5 cases, both the MCA territory and the watershed zone were involved in 10 cases. Of 12 patients with severe unilateral ICA stenosis and occlusion, CBF values of the watershed zone in nonsymptmatic and symptomatic sides were(41±9) and (38±8) ml· 100 g-1·min-1 respectively (t=2.08, P>0.05), the MTT values were (5.2±1.1) and (10.9±2.6) s, respectively (t=7.24, P<0.01). Thirteen patients with severe bilateral ICA stenosis or occlusion diagnosed by CTA had perfusion abnormalities in the both the MCA territory and the watershed zone. Of 25 patients with unilateral MCA stenosis, 4 patients were normal in CT perfusion, 17 patients had perfusion abnormalities in MCA territory, and 4 patients had perfusion abnormalities in both MCA territory and the watershed zone. Twelve patients with severe bilateral MCA stenosis diagnosed by CTA had perfusion abnormalities in both the MCA territory and the watershed zone. Compared to normal control, the MTF and TTP were increased, the CBF was decreased, and the CBV in MCA territory and the watershed zone at the symptomatic side was increased. Conclusion: The combined examination

  20. Measurements of patient chest dose for multi-slice X-ray CT examinations using PIN photodiode dosimeters

    Organ and tissue doses delivered during chest CT examinations were measured as a function of scanning parameters including tube current, slice thickness, and pitch of the multi-slice CT scanner. Measurements were carried out by using a chest dosimetry phantom that incorporated lung and vertebra models, and by putting PIN photodiode dosimeters into the phantom at sites of the esophagus or stomach, lung, bone marrow, and skin. Absorbed doses at each site in the phantom measured for a constant scan area indicated that these values could be precisely calculated from the value obtained at any scanning parameter by using inverse proportionality of dose to pitch and the data of x-ray intensity as a function of tube current and slice thickness measured for the CT scanner used. Relative dose at each site was found to be constant regardless of the scanning parameters, indicating that the dose value at each site could be calculated from that measured at only one point in the phantom. Effective doses and effective dose equivalents were estimated from organ or tissue doses for chest CT examinations, and were found to be 1.5 to 3 times larger than the average values of effective dose equivalent appearing in the literature. (author)

  1. Radiation exposure in multi-slice versus single-slice spiral CT: results of a nationwide survey

    Multi-slice (MS) technology increases the efficacy of CT procedures and offers new promising applications. The expanding use of MSCT, however, may result in an increase in both frequency of procedures and levels of patient exposure. It was, therefore, the aim of this study to gain an overview of MSCT examinations conducted in Germany in 2001. All MSCT facilities were requested to provide information about 14 standard examinations with respect to scan parameters and frequency. Based on this data, dosimetric quantities were estimated using an experimentally validated formalism. Results are compared with those of a previous survey for single-slice (SS) spiral CT scanners. According to the data provided for 39 dual- and 73 quad-slice systems, the average annual number of patients examined at MSCT is markedly higher than that examined at SSCT scanners (5500 vs 3500). The average effective dose to patients was changed from 7.4 mSv at single-slice to 5.5 mSv and 8.1 mSv at dual- and quad-slice scanners, respectively. There is a considerable potential for dose reduction at quad-slice systems by an optimisation of scan protocols and better education of the personnel. To avoid an increase in the collective effective dose from CT procedures, a clear medical justification is required in each case. (orig.)

  2. Low-dose multi-slice CT (LMCT) assessment of pulmonary emphysema in public-school teachers

    Although rates of emphysematous change in smokers have been reported previously, the precise effects of smoking on emphysematous change have not been established because the study subjects of previous reports were heterogeneous. This study was designed to determine the incidence of emphysematous change identified by low-dose multi-slice CT (LMCT) imaging in public-school teachers. We reviewed 1776 consecutive subjects (ages from 31 to 61 years) who had undergone LMCT scanning during health care examinations. In addition, their replies to questionnaires about smoking were obtained. Emphysematous change was found by LMCT imaging in 22 male smokers. In these 22 smokers, the scores of emphysematous change according to Goddard's method was well correlated with smoking history. According to the questionnaires, the smoking rates of male and female teachers were 56.7% and 4%, respectively. Eighty-five percent of the teachers worked in offices separated from smokers. Most smokers wished to quit smoking and most teachers knew the risk of nicotine as well as the rate of smoking among high school students. However, knowledge of the relationships between smoking and lung cancer, myocardial infarction, and subarachnoid hemorrhage were not adequate. Our present study clearly demonstrated the incidence of emphysematous change in school teachers. In addition, early exposure to information about the risks of smoking is believed to be important for students, but school teachers did not have enough of such information. (author)

  3. Juxta-adrenal schwannoma: Dynamic multi-slice CT and MRI findings

    Background: We retrospectively analyzed the MSCT and MRI findings of three cases of juxta-adrenal schwannoma and reviewed literature. Methods and results: Three patients were male, and showed no signs for endocrine activity. The three cases of juxta-adrenal schwannoma were all well-circumscribed, oval masses with cystic components, and one case with hemorrhage. Hypointense signal capsules were observed on T2-weighted images in two cases, and the capsule in one case showed rim enhancement. The tumors displayed mild enhancement in the arterial phase and progressive enhancement during the portal venous phase and equilibrium phase. Computed tomography angiography clearly showed the tumor feeding vessels arising from the abdominal aorta. Conclusions: MSCT and MRI are valuable imaging modalities for diagnosis of juxta-adrenal schwannoma.

  4. Evaluation of spinal cord vessels using multi-slice CT angiography

    陈爽; 钱建国; 冯晓源

    2004-01-01

    @@ Compared with the large number of head and neck vascular studies, computer tomography (CT) angiography of spinal vascular lesions has received relatively little attention. Several series and a few isolated cases of spinal vascular malformations demonstrated with magnetic resonance (MR) angiography have been reported.1-3 Selective digital subtraction angiography (DSA) is gold standard for diagnosis of spinal vascular lesions.4 However, it is invasive, time consuming, expensive, and dependent on the skills of the operator. Based on the DSA appearance and the surgical findings, spinal vascular malformations are generally, although not universally, classified as intradural (intramedullary and/or extramedullary) arteriovenous malformation (AVM) or arteriovenous fistula (AVF), and dural AVF. Recommended treatments of dural AVF consist of surgical obliteration and/or embolization.5-8

  5. Fast high resolution reconstruction in multi-slice and multi-view cMRI

    Velasco Toledo, Nelson; Romero Castro, Eduardo

    2015-01-01

    Cardiac magnetic resonance imaging (cMRI) is an useful tool in diagnosis, prognosis and research since it functionally tracks the heart structure. Although useful, this imaging technique is limited in spatial resolution because heart is a constant moving organ, also there are other non controled conditions such as patient movements and volumetric changes during apnea periods when data is acquired, those conditions limit the time to capture high quality information. This paper presents a very fast and simple strategy to reconstruct high resolution 3D images from a set of low resolution series of 2D images. The strategy is based on an information reallocation algorithm which uses the DICOM header to relocate voxel intensities in a regular grid. An interpolation method is applied to fill empty places with estimated data, the interpolation resamples the low resolution information to estimate the missing information. As a final step a gaussian filter that denoises the final result. A reconstructed image evaluation is performed using as a reference a super-resolution reconstructed image. The evaluation reveals that the method maintains the general heart structure with a small loss in detailed information (edge sharpening and blurring), some artifacts related with input information quality are detected. The proposed method requires low time and computational resources.

  6. Assessment of volumetric bone mineral density of the femoral neck in postmenopausal women with and without vertebral fractures using quantitative multi-slice CT

    Sheng-yong WU; Hui-hui JIA; Didier HANS; Jing LAN; Li-ying WANG; Jing-xue LI; Yue-zeng CAI

    2009-01-01

    Objective: To demonstrate the validity and reliability of volumetric quantitative computed tomography (vQCT) with multi-slice computed tomography (MSCT) and dual energy X-ray absorptiometry (DXA) for hip bone mineral density (BMD) measurements, and to compare the differences between the two techniques in discriminating postmenopausal women with osteoporosis-related vertebral fractures from those without. Methods: Ninety subjects were enrolled and divided into three groups based on the BMD values of the lumbar spine and/or the femoral neck by DXA. Groups 1 and 2 consisted of postmenopausal women with BMD changes <-2SD, with and without radiographically confirmed vertebral fracture (n=11 and 33, respectively).Group 3 comprised normal controls with BMD changes ≥-1SD (n=46). Post-MSCT (GE, LightSpeed16) scan reconstructed images of the abdominal-pelvic region, 1.25 mm thick per slice, were processed by OsteoCAD software to calculate the following parameters: volumetric BMD values of trabecular bone (TRAB), cortical bone (CORT), and integral bone (INTGL) of the left femoral neck, femoral neck axis length (NAL), and minimum cross-section area (mCSA). DXA BMD measurements of the lumbar spine (AP-SPINE) and the left femoral neck (NECK) also were performed for each subject. Results: The values of all seven parameters were significantly lower in subjects of Groups 1 and 2 than in normal postmenopausal women (P<0.05, respectively).Comparing Groups 1 and 2, 3D-TRAB and 3D-INTGL were significantly lower in postmenopausal women with vertebral fracture(s) [(109.8±9.61) and (243.3±33.0) mg/cm3, respectively] than in those without [(148.9±7.47) and (285.4±17.8) mg/cm3,respectively] (P<0.05, respectively), but no significant differences were evident in AP-SPINE or NECK BMD. Conclusion: the femoral neck-derived volumetric BMD parameters using vQCT appeared better than the DXA-derived ones in discriminating osteoporotic postmenopausal women with vertebral fractures from

  7. Quantitative assessment of pulmonary function using low dose multi-slice spiral CT in smoker

    Objective: To evaluate the clinical feasibility of low dose MSCT for quantitative assessment of pulmonary function in smokers. Methods: One hundred and forty-six patients with chronic objective pulmonary disease (COPD) including 109 smokers (74.6%) and 37 non-smokers (25.3%) underwent pulmonary function test and low-dose MSCT scan. All data were analyzed using computer-aided lung analysis software. Pulmonary function parameters from low-dose MSCT were compared between smokers and non-smokers and also compared with pulmonary function test in non-smokers (Pearson test). Results: In smokers, the average volume at full inspiratory phase (Vin) was (5125 ± 862 ) ml, mean lung attenuation was (-902 ± 26) HU, mean lung density was (0.0984 ± 0.0260 ) g/cm3, emphysema volume was (2890 ±1370) ml. The average volume at full expiratory phase (Vex) was (2756 ±1027) ml, mean lung attenuation was (-811 ±62) HU, mean lung density was (0.1878 ±0.0631) g/cm3, emphysema volume was (685 ±104) ml. In non-smokers, the average Vin was (3734 ± 759) ml, mean lung attenuation was (-876 ±40) HU,mean lung density was (0.1244 ±0.0401)g/cm3, emphysema volume was ( 1503 ± 1217) ml. The average Vex was (1770 ± 679) ml, mean lung attenuation was (-765 ± 56) HU, mean lung density was (0.2360 ± 0.0563) g/cm3, emphysema volume was (156 ± 45) ml. There were significant differences between smokers and non-smokers (P<0.01). The Vex/Vin was correlated with residual volume/total lung capacity (RV/TLC, r=0.60, P<0.01), and Vin was correlated with TLC (r=0.58, P<0.01), Vex with RV (r=0.59, P<0.01). Pixel index (PI) -950 in was correlated with FEV 1% pre and FEV1/FVC% (r=-0.53, -0.62, respective, P<0.01), Pl-950ex was correlated with FEV1 % pre and FEV1/FVC% (r=-0.71, -0.77, respective, P<0.01). Conclusion: Low-dose MSCT can be a potential imaging tool for quantitative pulmonary function assessment in smokes. (authors)

  8. Imaging skeletal anatomy of injured cervical spine specimens: comparison of single-slice vs multi-slice helical CT

    Our objective was to compare a single-slice CT (SS-CT) scanner with a multi-slice CT (MS-CT) scanner in the depiction of osseous anatomic structures and fractures of the upper cervical spine. Two cervical spine specimens with artificial trauma were scanned with a SS-CT scanner (HighSpeed, CT/i, GE, Milwaukee, Wis.) by using various collimations (1, 3, 5 mm) and pitch factors (1, 1.5, 2, 3) and a four-slice helical CT scanner (LightSpeed, QX/i, GE, Milwaukee, Wis.) by using various table speeds ranging from 3.75 to 15 mm/rotation for a pitch of 0.75 and from 7.5 to 30 mm/rotation for a pitch of 1.5. Images were reconstructed with an interval of 1 mm. Sagittal and coronal multiplanar reconstructions of the primary and reconstructed data set were performed. For MS-CT a tube current resulting in equivalent image noise as with SS-CT was used. All images were judged by two observers using a 4-point scale. The best image quality for SS-CT was achieved with the smallest slice thickness (1 mm) and a pitch smaller than 2 resulting in a table speed of up to 2 mm per gantry rotation (4 points). A reduction of the slice thickness rather than of the table speed proved to be beneficial at MS-CT. Therefore, the optimal scan protocol in MS-CT included a slice thickness of 1.25 mm with a table speed of 7.5 mm/360 using a pitch of 1.5 (4 points), resulting in a faster scan time than when a pitch of 0.75 (4 points) was used. This study indicates that MS-CT could provide equivalent image quality at approximately four times the volume coverage speed of SS-CT. (orig.)

  9. Effect of different injection rates of contrast medium on hepatic perfusion by using multi-slice spiral CT

    Objective: To access the effect of different injection rates of contrast medium on hepatic perfusion by using multi-slice spiral CT (MSCT). Methods: Sixty volunteers underwent liver dynamic CT scan, they were divided into three groups according to different injection rate of contrast medium (4 ml/s, 5 ml/s, and 7 ml/s, respectively). Their hepatic perfusion parameters were calculated and the results were compared between the three groups. Results: There are five perfusion data: hepatic arterial perfusion (HAP), hepatic portal perfusion (HPP), total liver perfusion (TLP), hepatic arterial perfusion index (HPI), hepatic portal perfusion index ( PPI). There is no significant difference of all indexes when compared 4 ml/s to 5 ml/s group, and 5 ml/s to 7 ml/s group, whereas HAP, HPP and TLP of 4 ml/s group were significant higher than those of 7 ml/s group. HAP: (0.37 ± 0.16) ml·min-1·ml-1 vs (0.26 ± 0.10) ml·min-1·ml-1, t=0.105, P=0.010; HPP: (0.68 ±0.19) ml·min-1 ml-1 vs (0.51±0.13) ml·min-1·ml-1, t=0.172, P=0.001; TLP: (1.05±0.30) ml·min-1·ml-1 vs (0.77±0.18) ml·min-1·ml-1, t=0.277, P=0.001. Conclusion: When evaluate liver perfusion with MSCT, the higher the injection rate of contrast medium, the lower the perfusion data. In clinical practice, perfusion effect, security and condition of patient should thought over to select a proper injection rate. To this study, 5 ml/s is enough. (authors)

  10. 低仟伏64层MSCT扫描对泌尿系结石检出的研究%Low kilovotage 64-slice spiral CT in the detection of urinary calculus:an experimental study

    王秋霞; 陈亮; 黄文华; 胡道予

    2011-01-01

    目的:探讨低仟伏值(kV)低辐射量MSCT扫描对泌尿系结石的检出率及对图像质量的影响.方法:将4种单一成分的泌尿系结石108粒放入猪里脊肉内制成结石模型,应用64层螺旋CT对模型进行扫描,扫描的管电压分别为120 kV、100 kV和80 kV,并与不同的管电流进行组合,层厚为5 mm,层间距为5 mm,螺距为0.984.扫描后的原始数据(5mm层厚)重建成1.25mm层厚,使用GE ADW4.3工作站对数据进行处理.测量图像质量的噪声水平,记录X线辐射剂量指标CTDIvol.结果:与对照组120kV-250mAs相比,实验组80kV-150mAs及100kV-50mAs组的噪声SD值仅分别升高7.60%和8.62%,主观评分均为合格,结石检出率为100%,而辐射剂量降低率分别达到81.40%和87.60%.结论:合适的低kV-mAs组合对泌尿系结石的检出率可以达到100%,且明显降低辐射剂量.%Objective : To investigate the detectability of urinary calculi undergoing 64-slice CT scanning with reducing kV and to evaluate the image quality,so as to obtain the optimal scanning program. Methods : The calculi model was made by inserting 108 granules of urinary calculus containing four kinds of simple constituent into pork loin,and then scanned by 64-slice CT. The scanning parameters were as follows : three different dose-groups were chosen according to the fixed kV set 120kV, 100kV , 80kV : slice thickness and interval 5mm ; the pitch is 0.984; the raw data were reconstructed into 1.25mm ; all the reconstructed images were transferred to GE ADW4.3 workstation. To evaluate image quality according to different dose-groups and counted the number of detected calculus respectively. The standard deviation (SD) and signal to noise ratio (SNR) of the images were measured. CT dose index volume (CTDIvol) was obtained automatically. Results: 120kV~250mAs was set to be the control group. Compared with the control group,80kV-150mAs,100kV~50mAs and 120kV~30mAs noise SD values were only increased by 7.60 %,8

  11. Application of low-dose 64-slice spiral CT scanning technology in adenoidal hypertrophy in children%64层CT对儿童腺样体肥大低剂量扫描的应用

    黄冰; 杨玲; 桂绍高

    2014-01-01

    Objective To investigate clinical application value of low-dose 64-slice spiral CT scanning technology in the ade-noidal hypertrophy of children. Methods 100 cases of children with adenoidal hypertrophy underwent low-dose(group A)and con-ventional-dose (group B)64-slice spiral CT scanning. The A/N ratio,Dand radiation dose in two groups were compared. Results The A/N ratio (P=0.981) and D (P=0.199) showed no significant difference between low-dose CT scanning and conventional-dose CT scanning (P=0.981). The CTDIvol of low-dose CT scanning was 6.93mGy and the CTDIvol of conventional-doses was 27. 92mGy. The CTDIvol of low-dose CT scanning decreased about 75%as compared with those of conventional dose scanning. Con-clusion The diagnostic result of image of low dose CT scanning is the same as that of conventional dose scanning,and the low-dose spiral CT scanning in children with adenoidal hypertrophy can substitute the conventional-dose spiral CT scanning.%目的:探讨低剂量64层螺旋CT扫描技术在儿童腺样体肥大中的应用。方法对100例临床疑似腺样体肥大儿童行64层螺旋CT低剂量和常规剂量扫描,将其随机分为两组,对比两种剂量扫描的鼻咽气腔前后径A/N比值和鼻咽气腔有效气道的前后径(D值)及患者的辐射剂量。结果64层螺旋CT低剂量扫描与常规剂量扫描之间鼻咽气腔前后径A/N比值无统计学差异(P=0.981);低剂量组与常规剂量组鼻咽气腔有效气道的前后径(D值)无统计学差异(P=0.199)。低剂量CT扫描显示儿童鼻咽部容积CT剂量指数CTDIvol为6.93mGy,常规剂量CTDIvol为27.92mGy。低剂量与常规剂量相比,其CTDIvol降低了约75%的辐射剂量。结论64层螺旋CT低剂量扫描对腺样体肥大的诊断结果与常规剂量均相同,故64层螺旋CT低剂量扫描临床疑似腺样体肥大的患者,完全能替代常规剂量的64层螺旋CT扫描。

  12. 混合性生殖细胞瘤的64层螺旋CT诊断及病理表现%Diagnosis of mixed germ cell tumor by 64-slice spiral CT and pathological manifestations

    朱刚明; 谭琦碹; 钟胜; 李兆勇; 付东

    2011-01-01

    目的:探讨64层螺旋CT对混合性生殖细胞瘤的诊断价值.方法:回顾性分析7例经病理证实的混合性生殖细胞瘤的CT平扫及两期增强表现、病理标本及切片特征.结果:7例病灶3例位于卵巢,3例位于前纵隔.1例位于睾丸;其中3例边界清楚;各病灶密度不均匀,内见囊变、坏死区,1例可见脂肪及钙化:增强扫描静脉期较动脉期强化明显,均呈不均匀强化.病理结果2例卵黄囊瘤与成熟畸胎瘸混合型.2例卵黄囊瘤与未成熟畸胎瘤混合型.1例卵黄囊瘤、胚胎性癌、畸胎瘤混合型,1例绒癌与无性细胞癌混合型,1例精原细胞瘤、胚胎性癌、滋养细胞成分混合型.结论:64层螺旋CT对混合性生殖细胞瘤的诊断虽无特异性,但在一定程度上为肿瘤良恶性判断、临床分期提供十分重要的依据.%Objective:To investigate the diagnostic value of mixed germ cell tumor by 64 -slice spiral CT. Methods: The plain CT and two-phase enhanced CT scanning and pathological specimens of 7 cases of the tumor confirmed by pathology were retrospectively studied. Results: 3 cases were found in ovarian and 3 cases in anterior mediastinum and 1 case in testis. 3 lesions were clear boundary, with fat and calcification in 1 lesion. All the lesions were uneven density and the cystic or necrotic area could be found. Venous phase enhancement was significantly higher than other phase, showed inhomogc-neous enhance. Pathological findings: induded 2 cases of yolk sac tumor and mature teratoma mixed. 2 cases of yolk sac tumor and immature teratoma mixed, 1 case of yolk sac tumor embryonal carcinoma and teratoma mixed. 1 case of chorio-carcinoma and asexual cell carcinoma mixed, and 1 case of seminoma embryonal carcinoma and trophoblastic ingredients mixed. Conclusion: Although there is no specific by 64-slice spiral CT. To a certain degree.it can determine the benign or malignant tumor and give the important prop for clinical staging.

  13. 64层螺旋CT低剂量扫描在新生儿气胸诊断中的应用%Low dose scanning of 64 slice spiral CT in the diagnosis of pneumothorax in neonates

    武军; 李彦杰

    2015-01-01

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

  14. Correlation of 64-slices CT Features with Vascular Endothelial Growth Factor Expression in Brain Astrocytoma%VEGF在脑星形细胞瘤中的表达与64排CT征象的关系

    蔡胜艳; 孙妍; 胡嘉航

    2012-01-01

    目的:探讨脑星形细胞瘤64排CT征象与VEGF表达之间的关系.方法:搜集经手术证实的脑星形细胞瘤30例,分析其CT表现,术后对肿瘤组织标本进行免疫组化染色,分析其VEGF表达的程度与CT征象之间的关系.结果:星形细胞瘤的VEGF表达程度与肿瘤的分级、瘤周水肿的范围及肿瘤的强化程度有相关性.结论:星形细胞瘤的CT表现可以反映VEGF的表达程度,能对临床治疗方案的选择和患者预后的评估起到重要作用.%Objective To study the correlation of 64-slices CT features with vascular endolhelial growth factor(VEGF) expression in brain astrocytoma. Methods CT findings in 30 cases with surgically and pathologically proved astrocytoma were retrospectively analyzed. VEGF was stained with immuno- histochemical technique, and VEGF expression levels were compared with CTfeatures. Results VEGF expression levels were with correlated with pathological grade, the extent of per tumor edema and the degree of contrast enhancement. Conclusion CT features of astrocytoma can reflect VEGF expression levels. It is important for the choice of clinical treatment and prognostic evaluation of patients. [Chinese Medical Equipment Journal,2012,33(6):67-68

  15. Interrupted aortic arch diagnosed by ECG-gated multi-slice computed tomography angiography: a case report

    ZHOU Yang-yang; HAN Ping; FENG Gan-sheng; LIANG Bo

    2005-01-01

    @@ Interrupted aortic arch (IAA) is a rare congenital cardiovascular disease with major intracardiac defects and always with multisystem non-cardiac malformations. It occurs in 1: 10,000 births, and about 1% of the patients with congenital heart defects.

  16. Measurement of multi-slice computed tomography dose profile with the Dose Magnifying Glass and the MOSkin radiation dosimeter

    This study describes the application of two in-house developed dosimeters, the Dose Magnifying Glass (DMG) and the MOSkin dosimeter at the Centre for Medical Radiation Physics, University of Wollongong, Australia, for the measurement of CT dose profiles for a clinical diagnostic 16-slice MSCT scanner. Two scanner modes were used; axial mode and helical mode, and the effect of varying beam collimation and pitch was studied. With an increase in beam collimation in axial mode and an increase of CT pitch in helical mode, cumulative point dose at scanner isocentre decreased while FWHM increased. There was generally good agreement to within 3% between the acquired dose profiles obtained by the DMG and the film except at dose profile tails, where film over-responded by up to 30% due to its intrinsic depth dose dependence at low doses. -- Highlights: ► This study shows the CT beam profiles acquired with our institution's detectors. ► The DMG is a relative dosimeter calibrated to absolute MOSkin readings. ► There was good agreement between dose profiles acquired by the DMG and the film

  17. Radiological patterns of primary graft dysfunction after lung transplantation evaluated by 64-multi-slice computed tomography

    Belmaati, Esther Okeke; Steffensen, Ida; Jensen, Claus Verner;

    2012-01-01

    found in patients with PGD. There were no vascular changes found at CT angiographies. The most severe cases of GG opacities and consolidation were found in patients with PGD. ST seems to be an important indicator of PGD. HRCT(64-MSCT) imaging may be a useful tool for the identification of pathological...

  18. Multi-slice computed tomography as a screening tool for colon cancer, lung cancer and coronary artery disease

    Recent promising trials that use low-dose CT for the early detection of lung cancer have reinvigorated the interest in screening approaches. At the same time the development of fast image acquisition techniques, such as multislice CT, have sparked renewed interest in cardiac imaging within the radiological community. In addition to special cardiac capabilities, multislice CT has several other features such as high acquisition speed and low-dose requirements that may make this modality a universal radiological screening tool. Non-invasive disease detection is the radiologist's domain. In this paper we identify criteria for effective screening and apply these criteria to screening approaches with multislice CT when used for detection of three disease entities: colon cancer; lung cancer; and cardiovascular disease. (orig.)

  19. Organ point dose measurements in clinical multi slice computed tomography (MSCT) examinations with the MOSkin™ radiation dosimeter

    This study reports on the application of the MOSkin™ dosimeter in MSCT imaging for the real-time measurement of absorbed organ point doses in a tissue-equivalent female anthropomorphic phantom. MOSkin™ dosimeters were placed within the phantom to measure absorbed point organ doses for 2 commonly applied clinical scan protocols, namely the renal calculus scan and the pulmonary embolus scan. Measured organ doses in the imaged field of view were found to be in the dose range 4.7–9.5 mGy and 16.2–27.4 mGy for the renal calculus scan and pulmonary scan protocols respectively. For the derivation of effective dose, using the more recent ICRP 103 tissue weighting factors (wT) compared to that of the ICRP 60 wT resulted in a difference in the derived effective dose by up to 0.8 mSv (−20%) in the renal calculus protocol and up to 1.8 mSv (18%) in the pulmonary embolus protocol. This difference is attributed to the reduced radiosensitivity of the gonads and the increased radiosensitivity of breast tissue in the latest ICRP 103 assigned wT. The results of this study show that the MOSkin™ dosimeter is a useful real-time tool for the direct assessment of organ doses in clinical MSCT examinations. -- Highlights: •The MOSkin™ dosimeter was used to measure CT organ point doses. •Effective doses varied depending on ICRP 60 or 103 wT factors used in the derivation. •The results show that the MOSkin™ dosimeter is a useful real-time clinical dosimetry tool

  20. Exploiting sparsity and low-rank structure for the recovery of multi-slice breast MRIs with reduced sampling error.

    Yin, X X; Ng, B W-H; Ramamohanarao, K; Baghai-Wadji, A; Abbott, D

    2012-09-01

    It has been shown that, magnetic resonance images (MRIs) with sparsity representation in a transformed domain, e.g. spatial finite-differences (FD), or discrete cosine transform (DCT), can be restored from undersampled k-space via applying current compressive sampling theory. The paper presents a model-based method for the restoration of MRIs. The reduced-order model, in which a full-system-response is projected onto a subspace of lower dimensionality, has been used to accelerate image reconstruction by reducing the size of the involved linear system. In this paper, the singular value threshold (SVT) technique is applied as a denoising scheme to reduce and select the model order of the inverse Fourier transform image, and to restore multi-slice breast MRIs that have been compressively sampled in k-space. The restored MRIs with SVT for denoising show reduced sampling errors compared to the direct MRI restoration methods via spatial FD, or DCT. Compressive sampling is a technique for finding sparse solutions to underdetermined linear systems. The sparsity that is implicit in MRIs is to explore the solution to MRI reconstruction after transformation from significantly undersampled k-space. The challenge, however, is that, since some incoherent artifacts result from the random undersampling, noise-like interference is added to the image with sparse representation. These recovery algorithms in the literature are not capable of fully removing the artifacts. It is necessary to introduce a denoising procedure to improve the quality of image recovery. This paper applies a singular value threshold algorithm to reduce the model order of image basis functions, which allows further improvement of the quality of image reconstruction with removal of noise artifacts. The principle of the denoising scheme is to reconstruct the sparse MRI matrices optimally with a lower rank via selecting smaller number of dominant singular values. The singular value threshold algorithm is performed

  1. Low-dose multi-slice CT with three dimensional rendering of the tendons of foot and ankle

    Objective: To study the feasibility and reasonability of low-dose multi-slice CT (MSCT) with three dimensional rendering of the tendons of foot, and ankle. The statistical methods including ANOVA and Kruskal-Wallis H was used. Methods: Forty-five consecutive patients with fractures of foot and ankle were enrolled and evenly grouped into A(80 kV, 100 mAs), B (110 kV, 60 mAs) and C (130 kV, 60 mAs). The MSCT scanning range was 6 slices of 1.0 mm. The CT value and standard deviation (SD) of the muscle and the CTDIvol were recorded. The image quality of volume rendering of the tendons was blindly evaluated. Results: The CT value of muscle in group A (71.6±12.0) HU was significantly higher than group B [(66.8±9.2) HU, P=0.010] and C [(66.1±7.1) HU, P=0.004]. The SD average values were 11.9, 6.1 and 7.0 HU for three groups, and there were significant differences among the three groups (F= 37.142, P=O.0000). Group A had the highest SD value, group C had the lowest. SD; CTDIvol average value were (3.01±0.08), (4.63±0.11), (7.02±0.24) mGy respectively, which were significant different among the three groups (H =39.185, P=0.000). Group A had the lowest CTDIvol, while group C had the highest CTDIvol. Volume rendering of the tendons was evaluated as 2.3±0.5, 3.7±0.5, 4.8± 0.4, and there were significant differences among the three groups (H=72.779, P=0.000). Group A had the worst VR images, while group C had the best VR images. All VR images in Group B were good for diagnosis. Conclusion: The protocol of 110 kV, 60 mAs, and 1 mm × 6 with three-dimensional volume rendering would be enough for evaluating the tendons of foot and ankle. (authors)

  2. Evaluation of the effects of tirofiban on myocardial infarction-reperfusion injury by delayed enhancement multi-slice spiral CT

    Objective: To evaluate the effects of tirofiban on myocardial no-reflow after acute myocardial infarction and reperfusion by delayed enhancement-multi-slice CT (DE-MSCT). Methods: Chinese mini pigs were randomized into control group and tirofiban treatment group. Acute myocardial infarction was induced by balloon occlusion of the medium segment of the left anterior descending artery for 90 minutes. Reperfusion was created by withdrawing the balloon during angiography. All successful models received DE-MSCT examinations at 1 h, 24 h, 48 h, and 72 h after reperfusion to observe the myocardial no- reflow area. Data were analyzed with Spearman rank correlation and Wilcoxon, Rank Sum test. Results: Six pigs were successfully induced as acute reperfusion myocardial infarction in each group. Furthermore,4 pigs in control group and 3 pigs in tirofiban treatment group had no-reflow phenomenon. The no-reflow volume percent increased from 1 h to 72 h in both groups. The no-reflow volume percent was significantly reduced in tirofiban treatment group compared with control group after reperfusion at 1 h, 24 h, 48 h and 72 h respectively [(4.78±0.66)% and (9.62±3.05)%, t=6.000, P<0.05; (5.84±1.19)% and (13.44±3.33)%, t=6.000, P<0.05; (6.41±1.24)% and (15.10±3.76)%, t=6.000, P<0.05; (6.63±0.82)% and (15.94±4.62)%, t=6.000, P<0.05], as well as the infarct myocardium volume percent was significantly reduced in tirofiban treatment group compared with control group at 24 h, 48 h and 72 h after reperfusion [(19.74±2.94)% and (25.08±4.68)%, t=25.000, P<0.05; (20.34±2.46)% and (27.07±5.44)%, t=26.000, P<0.05; (20.72±2.10)% and (26.17±5.19)%, t=24.000, P< 0.05]. Conclusions: DE-MSCT can be used to detect the extent of no-reflow phenomenon. Tirofiban can reduce the volume of myocardial infarct and no-reflow area after reperfusion. (authors)

  3. Study of low dose and dynamic multi-slice CT about obstructive sleep apnea syndrome in sleeping

    Objective: To perform Low dose dynamic MSCT(multi-slice CT) in sleeping obstructive sleep apnea syndrome (OSAS) patients correcting the imprecise measure values in waking state, and to exactly analyse the location and extension of the dynamic changes about the condition. Methods: Sixteen OSAS patients were scanned both in waking and naturally sleeping period (end phase of inspiration and expiration). Measured at the narrowest part of the retropalatal (RP) and retroglossal (RG) and 5 mm under the tip of epiglottis at the epiglottal (EPG)at the end period of inspiration in sleeping, respectively, and compared the accurate position of the narrowest or occlusive level in 3 phases. All patients were also scanned using cine mode at the narrowest level at the end period of inspiration in sleeping to show the pharyngeal cavity changes during sleep. Results: The smallest XSA of RP region (Mw=47.50 mm2, Me=73.00 mm2, Mi=2.00 mm2; Zwe=2.897, Pwe=0.003; Zwi=4.192, Pwiie=4.538, Piew=8.00 mm, Me=9.50 mm, Mi=1.50 mm; Zwe=1.933, Pwe=0.056; Zwi=3.720, Pwiie=4.230, Piew=8.00 mm, Me=9.00 mm, Mi=1.00 mm; Zwe=1.210, Pwe=0.246; Zwi=4.203, Pwiie=4.557, Piew=4.00 mm3, Me=5.50 mm3, Mi=1.50 mm3; Zwe=1.576, Pwe=0.125; Zwi=3.532, Pwiie=4.077, Piew=7.00 mm, Me=6.00 mm, Mi=10.50 mm; Zwe=0.557, Pwe=0.603; Zwi=2.541, Pwi=0.011; Zie=2.852, Pie=0.004) and RG regions (Mw=5.00 mm, Me=3.00 mm, Mi=9.50 mm; Zwe=0.747, Pwe=0.482; Zwi=2.657, Pwi=0.007; Zie=3.075, Pie=0.001), were different between inspiration and expiration of sleeping or awake. The dynamic cine CT scan during sleeping could show pharyngeal change, clearly. Conclusion: At the end period of inspiration in sleeping, the location of narrow or obstructive of airway is the most precise and sensitive and the false negative at the waking could be obviously reduced. Low dose MSCT scan reduced exposure and expense. (authors)

  4. The investigation of the lateral atlanto-dental interval of atlanto-axial joint by multi-slice spiral CT

    Objective: To explore imaging features of the lateral atlanto-dental interval (LADI) of atlanto-axial joint and its value in the diagnosis of atlanto-axial joint dislocation/subluxation. Methods: Two hundred and forty healthy volunteers without atlanto-axial joint dysfunction and 32 patients with torticollis and/or functional impairment at atlanto-axial.joint were enrolled into this study. All subjects were examined with multi-slice CT in both neutral and max rotation positions to the left/right. Clinical endpoints including VBLADI, variance range of the VBLADI and asymmetric conditions were evaluate. χ2 test is used to evaluate the variance of incidence of bilateral LADI asymmetry in different age groups, Pearson-test (2-tailed) is used to evaluate the correlation between VBLADI and rotary function of atlanto-axial joint, precise test of fourfold table is used to compare normal group with patient groups. Results: (1) In the normal control group: asymmetry of bilateral LADI were observed in 204 among 240 (85.00%) healthy volunteers including 60 youngsters (95% of ∣ VBLADI ∣ were 0.850 mm, 2.450 mm in the young (95% in the young and in the adult respectively. There was no correlation between VBLADI(-2.146 to 2.114 mm, Median 0.000 mm) and LA (22.949° to 44.649°, Median 34.500°), RA (25.284° to 45.334°, Median 35.300°), VLRA (-11.643° to 8.623°, median 0.000°) respectively in normal people (r=-0.030, -0.005, 0.026, P>0.05). (2) In the study with 32 patients including 25 youngsters (95% in group AALSD and group AACD than in abnormal group (P<0.01), but there is no difference between group AARD and normal group (P=0.738). Conclusion: The imaging finding of 'asymmetry of bilateral LADI' may be either a physiological variation or a pathological condition, clinical manifestations and other imaging findings should be evaluated to make a diagnosis. (authors)

  5. Comparative study of myocardial perfusion imaging and 64 multi-slice spiral CT for the diagnosis of coronary artery disease

    Objective: To compare the diagnostic value of myocardial perfusion imaging (MPI) and 64 multi-slice spiral CT (64-MSCT) for coronary artery disease (CAD). Methods: Fifty-two patients with suspected or known CAD were included in the study. Each patient underwent both stress and rest MPI, MSCT as well as conventional coronary angiography (CAG) within 1 month. The stress and rest MPI were scored by a 5-grade criteria (0-4) based on 17 coronary artery segments. The difference between summed stress and rest scores > 1 was defined as myocardial ischemia. Stenosis in one main vessel or one main branch of the main vessel ≥50% was defined as myocardial ischemia by MSCT. CAG was used as the reference for comparison. Statistical analysis was performed using SPSS 13.0 software. Kappa value was used to test the accordance of MPI and MSCT results. χ2 test was used to evaluate the difference between MPI and MSCT results. Results: The patient-based sensitivity, specificity, positive and negative predictive values and accuracy of MPI and MSCT for the diagnosis of CAD were 86.7% (26/30), 77.3% (17/22),83.9% (26/31), 81.0% (17/21), 82.7% (43/52) and 83.3% (25/30), 86.4% (19/22), 89.3%( 25/28), 79.2% (19/24), 84.6% (44/52), respectively. The vessel-based sensitivity, specificity, positive and negative predictive values and accuracy of MPI and MSCT were 74.5% (38/51), 81.0% (85/105), 65.5% (38/58), 86.7% (85/98), 78.8% (123/156) and 90.2% (46/51), 88.6% (93/105),79.3 % (46/58), 94.9% (93/98), 89.1% (139/156), respectively. There was no statistically significant difference between MPI and MSCT for either patient or lesion-based diagnosis (χ2 =0.44, 0.21, both P>0.05). 96.0% (24/25) patients with both abnormal MPI and MSCT positive were validated by CAG while 83.3% (15/18) patients with both MPI and MSCT negative were excluded by CAG. Conclusions: Both MPI and MSCT are reliable diagnostic modalities for CAD. They also provide complementary diagnostic value to each other. (authors)

  6. Investigation on the optical scan condition for imaging of multi-slice spiral CT liver perfusion in rats

    BAI Rong-jie; WANG Jin-e; JIANG Hui-jie; HAO Xue-jia; DONG Xu-peng; HUANG Ya-hua; WEI Lai

    2013-01-01

    Background Multi-slice CT liver perfusion has been widely used in experimental studies of hemodynamic changes in liver lesions,and is usually performed as an adjunct to a conventional CT examination because of its high temporal and spatial resolution,simple protocol,good reproducibility,and ability to measure hemodynamic changes of liver tissues at the capillary level.Experimental rat models,especially those of induced liver cancer,are often used in studies of hemodynamic changes in liver cancer.Carcinogenesis in rats has a similar pathological progression and characteristics resembling those in human liver cancer; as a result,rat models are often used as ideal animal models in the study of human liver cancer.However,liver perfusion imaging in rats is difficult to perform,because rats' livers are so small that different concentrations,flow rates,and dose of contrast agents during the CT perfusion scanning can influence the quality of liver perfusion images in rats.The purpose of this study,therefore,was to investigate the optimal scan protocol for the imaging of hepatic perfusion using a deconvolution mathematical method in rats by comparing the results of rats in different injection conditions of the contrast agent,including concentration,rate and time.Methods Plain CT scan conditions in eighty 2-month-old male Wistar rats were 5.0 mm slice thickness,5.0 mm interval,1.0 pitch,120 kV tube voltage,60 mA tube current,512×512 matrix,and FOV 9.6 cm.Perfusion scanning was carried out with different concentrations of diatrizoate (19%,38%,57%,and 76%),different injection rates (0.3 and 0.5 mi/s),and different injection times (1,2-3,4-5,and 6 seconds).The above conditions were randomly matched and adjusted to determine the best perfusion scan protocol.Thrae-phase contrast-enhanced scanning was performed after CT perfusion.Histological examination of the liver tissues with hematoxylin and eosin stains was done after CT scanning.Results When the concentration of the

  7. Peripheral pulmonary nodules: Relationship between multi-slice spiral CT perfusion imaging and tumor angiogenesis and VEGF expression

    , PS of inflammatory nodule were significantly lower than that of peripheral lung cancer (all P < 0.05). PH, PHpm/PHa, BF, and BV of benign nodule were significantly lower than those of inflammatory nodule (all P < 0.05), rather than PS and MTT (mean transit time) (all P > 0.05). PH, PHpm/PHa, BV, and PS of benign nodule were significantly lower than those of peripheral lung cancer (all P < 0.05). In the case of VEGF positive expression, MVD was positively correlated with PH, PHpm/PHa, BF, BV, and PS of peripheral lung cancer and PS of benign nodule (all P < 0.05). Multi-slice spiral CT perfusion imaging closely correlated with tumor angiogenesis and reflected MVD measurement and VEGF expression. It provided not only a non-invasive method of quantitative assessment for blood flow patterns of peripheral pulmonary nodules but also an applicable diagnostic method for peripheral pulmonary nodules

  8. 64层螺旋CT血管成像诊断大脑中动脉成窗变异%CT Angiography Features of Fenestration Variation in the Middle Cerebral Artery Using 64-slice Multidetector Spiral CT

    袁飞; 刘银社; 常爱华; 赵军; 顾欣; 冯凯琳

    2011-01-01

    目的 探讨大脑中动脉成窗变异的发生率及CT血管成像(CTA)特征,提高对该血管变异的认识.资料与方法 2007年11月至2010年1月本院共有2734例患者行头颈联合64层CTA检查,其中14例确诊为大脑中动脉成窗.回顾性分析大脑中动脉成窗的发生率、部位、形态等CTA特征及其合并症.结果 (1)14例患者共15个大脑中动脉成窗,发生率为0.51%(14/2734).M1段近端成窗12个,占80%;M1段远端成窗2个,占13.3%,均由一支桥血管与M1段远端及M2段近端构成;M1段中部成窗1个,占6.7%.M1段近端成窗中,9个成窗位于大脑中动脉起始部,3个成窗由一支桥血管与M1和A1近端三支血管组成.(2)2个"窗"径较小者(<2 mm)呈孔状,13个"窗"径较大者中,10个分支粗细不等呈"OK"手势样,3个分支粗细大致相同呈"凸透镜"样.(3)1例合并基底动脉成窗,1例合并大脑后动脉成窗,1例合并永久三叉动脉,3例合并颅内其他动脉的动脉瘤.结论 CTA能快速、直观、准确地判断大脑中动脉成窗及其合并症,熟悉其CTA特征有助于指导临床制定合理的治疗方案,提高相应治疗中的安全性.%Objective To analyze the incidence and CT angiography(CTA) features of the fenestrations variation of middie eerebral artery, and to improve dignesis. Materials and Methods The imaging data of 2734 patients peeformed 64 slice CTA of the cranio cervical arteries in our hospital between November,2007 and January 2010 were evaluated retrospectively,and 14 of them were diagnosed as the fenestration variation of middle cerebral arteries. The incidence,location,morpholngical characteristics of the fenestration of middle cerebral artery and its coexisting abnormalities were analyzed. Results ( 1 ) 15 fenestrations variation of middle cerebral arteries in 14 patients were found,withh the incidence of 0.51% ( 14/2734 ). 80%( 12 fenestrations) were located at the proximal Mi segments,13.3% (2 fenestrations) at the distal

  9. Multi-slice imAGe generation using intra-slice paraLLel imaging and Inter-slice shifting (MAGGULLI)

    Kim, Dongchan; Seo, Hyunseok; Oh, Changheun; Han, Yeji; Park, HyunWook

    2016-02-01

    For acceleration of imaging time, multi-band imaging techniques (e.g. CAIPIRINHA) use the sensitivity differences of the multi-channel RF coils in the slice selection direction. To more effectively utilize the RF coil characteristics than the conventional multi-band imaging techniques, we propose a new imaging technique, called multi-slice image generation using intra-slice parallel imaging and inter-slice shifting (MAGGULLI). The proposed technique used an inter-slice shifting gradient in slice selection direction to make multi-slice images shift in the frequency encoding direction. Thus, aliasing caused by sub-sampling in the phase encoding direction is orthogonal to that by multi-band imaging with the inter-slice shifting, both of which are resolved by using the sensitivity information of the RF coil. Phantom and in vivo imaging experiments for the acceleration factors up to 10 demonstrate that the quality of the images reconstructed by MAGGULLI are better than that of CAIPIRINHA for high acceleration factors in the qualitative and quantitative analysis.

  10. 3D visualisation of the middle ear and adjacent structures using reconstructed multi-slice CT datasets, correlating 3D images and virtual endoscopy to the 2D cross-sectional images

    The 3D imaging of the middle ear facilitates better understanding of the patient's anatomy. Cross-sectional slices, however, often allow a more accurate evaluation of anatomical structures, as some detail may be lost through post-processing. In order to demonstrate the advantages of combining both approaches, we performed computed tomography (CT) imaging in two normal and 15 different pathological cases, and the 3D models were correlated to the cross-sectional CT slices. Reconstructed CT datasets were acquired by multi-slice CT. Post-processing was performed using the in-house software ''3D Slicer'', applying thresholding and manual segmentation. 3D models of the individual anatomical structures were generated and displayed in different colours. The display of relevant anatomical and pathological structures was evaluated in the greyscale 2D slices, 3D images, and the 2D slices showing the segmented 2D anatomy in different colours for each structure. Correlating 2D slices to the 3D models and virtual endoscopy helps to combine the advantages of each method. As generating 3D models can be extremely time-consuming, this approach can be a clinically applicable way of gaining a 3D understanding of the patient's anatomy by using models as a reference. Furthermore, it can help radiologists and otolaryngologists evaluating the 2D slices by adding the correct 3D information that would otherwise have to be mentally integrated. The method can be applied to radiological diagnosis, surgical planning, and especially, to teaching. (orig.)

  11. Application of 64-slice spiral CT angiography in the diagnosis of tetralogy of fallot%64层螺旋CT血管造影在法洛四联症诊断中的应用

    陈红; 曹成瑛; 朱友义; 王生元; 罗焕; 周署泉

    2011-01-01

    目的:探讨64层螺旋CT血管造影(64-SCTA)诊断法洛四联症(tetralogy of Fallot,TOF)的应用价值.方法:回顾性分析23例TOF患者的64-SCTA诊断结果,并与心脏超声(UCG)和手术进行对比.结果:23例TOF患者经64-SCTA和UCG都能发现和准确诊断TOF的4种主要畸形,室间隔缺损大小、主动脉骑跨程度、右室流出道狭窄、右室前壁厚度以及主肺动脉内径的测量结果与手术结果比较均差异无统计学意义(均P>0.05);64-SCTA检出体肺侧支动脉血管6例,UCG仅检出1例,二者比较,差异有统计学意义(P<0.01).结论:64-SCTA能客观清晰地显示TOF的4种畸形,在心外大血管畸形诊断方面较UCG有明显的优势,是准确诊断TOF无创性检查的理想选择.%Objective!To evaluate the advantage and limitation of 64-slice spiral CT angiography (64-SCTA) in diagnosing tetralogy of fallot (TOF). Method:64-SCTA findings of 23 patients with TOF were retrospectively ana-lyzed comparatively with cardiac ultrasound and surgery. Result:Four major malformations of TOF could be accu-rately diagnosed by both 64-SCTA and cardiac ultrasound. There was no significant statistically difference (P> 0. 05) compared with that of surgery in evaluating the ventricular septal defect size, degree of aortic cross-riding, stenosis of right ventricular outflow, as well as internal diameter of main pulmonary, left and right pulmonary ar-tery, the right ventricular wall thickness were no significant statistically difference (P>0. 05) measured by 64-SC-TA and cardiac ultrasound, but 64-SCTA had more advantages than cardiac ultrasound in diagnosing the extracar-diac malformation (P<0. 01) , for the detection of lung body collateral arteries by 64-SCTA in 6cases, while only lease by cardiac ultrasound. Conclusion: Four major malformations of TOF could be objectively and clearly diag-nosed by 64-SCTA. In diagnosis of great extracardiac vessel malformations, 64-SCTA is significantly superior to UCG. 64

  12. Diagnosis of pulmonary embolism and the underlying venous thrombosis by multi-slice CT; Diagnostik der Lungenembolie und zugrundeliegender Venenthrombosen in der Mehrzeilen-Spiral-CT

    Mueller, C.; Kopka, L.; Funke, M.; Funke, C.; Grabbe, E. [Abt. Roentgendiagnostik I, Georg-August-Univ. Goettingen (Germany)

    2001-06-01

    To determine the value of multi-slice CT for the diagnosis of acute pulmonary embolism and an underlying venous thrombosis. Methods: 70 patients with clinically suspected acute pulmonary embolism were examined. Using multi-slice CT a combined examination of the pulmonary arteries and the veins of the lower limb, pelvis and abdomen was performed. Only one single bolus of 150 ml iopromid 300 was injected into a cubital vein with a flow of 4 ml/s. First, the pulmonary arteries were scanned with a slice thickness of 2.5 mm and a pitch of 1.5. On arrival of the contrast medium at the popliteal veins, indicated by bolus trakking, the veins of the lower limbs up to the end of the inferior vena cava were imaged using a slice thickness of 3.75 mm and a pitch of 1.5. The results could be compared with a ventilation-perfusion scan in 48 cases, with a Doppler ultrasound examination in 46 cases, and with a venography in 10 cases. Furthermore, the image quality of all arterial and venous regions was subjectively assessed. Results: In all patients who underwent multi-slice CT the pulmonary arteries as well as the veins of the lower half of the body could be recorded completely. Regarding the pulmonary arteries the image quality showed excellent results for the central and segmental arteries. The region up to the 3rd division in subsegmental branches could be sufficiently judged. More peripherally, a diagnostic assessment was not possible. The image quality of the veins was excellent in all sections, except the calf, where a reliable diagnosis could not be made. The comparison with the other techniques confirmed the superiority of multi-slice CT concerning the central and segmental pulmonary arteries and the veins from the popliteal vein to the inferior vena cava. In contrast, peripheral pulmonary emboli can be detected more certainly in ventilation/perfusion scans. The veins of the calf can be evaluated more reliably with venography. (orig.) [German] Evaluation der Moeglichkeiten

  13. Depiction of the triangular fibro-cartilage in patients with ulnar-sided wrist pain: comparison of direct multi-slice CT arthrography and direct MR arthrography

    Omlor, Georg; Jung, Martin [Orthopaedic University Hospital, Department of Hand and Elbow Surgery, Heidelberg (Germany); Grieser, Thomas; Ludwig, Karl [Orthopaedic University Hospital, Department of Diagnostic Radiology, Heidelberg (Germany)

    2009-01-15

    To compare direct multi-slice CT arthrography (MSCT-AG) and direct MR arthrography (MR-AG) of the wrist with regard to the depiction of the triangular fibro-cartilage (TFC). Fifteen consecutive patients with ulnar-sided wrist pain suspicious for TFC tear underwent both MSCT-AG and MR-AG of the wrist. Images obtained were evaluated by two radiologists in a blinded fashion for the depiction of six anatomical areas (radial, central and ulnar portion on the proximal and distal side) of the TFC by means of a five-point scoring system (1= excellent visibility to 5= not visible). Scores for MSCT-AG and MR-AG were compared using the Student's t-test. Mean scores for MSCT-AG and MR-AG, respectively, were 2.5/2.0, 3.2/2.5 and 2.8/2.4 for the radial, central and ulnar portion of the TFC on its proximal side, and 2.7/2.0, 3.1/2.3 and 2.9/2.4 for the radial, central and ulnar portion on its distal side (n=15). Paired Student's t-test showed no significant difference between MSCT-AG and MR-AG (P>0.05). In a first, small series, depiction of the TFC with MSCT-AG is comparable to that of MR-AG. Further evaluation of direct multi-slice CT arthrography of the wrist in a larger patient population would be promising. (orig.)

  14. Depiction of the triangular fibro-cartilage in patients with ulnar-sided wrist pain: comparison of direct multi-slice CT arthrography and direct MR arthrography

    To compare direct multi-slice CT arthrography (MSCT-AG) and direct MR arthrography (MR-AG) of the wrist with regard to the depiction of the triangular fibro-cartilage (TFC). Fifteen consecutive patients with ulnar-sided wrist pain suspicious for TFC tear underwent both MSCT-AG and MR-AG of the wrist. Images obtained were evaluated by two radiologists in a blinded fashion for the depiction of six anatomical areas (radial, central and ulnar portion on the proximal and distal side) of the TFC by means of a five-point scoring system (1excellent visibility to 5= not visible). Scores for MSCT-AG and MR-AG were compared using the Student's t-test. Mean scores for MSCT-AG and MR-AG, respectively, were 2.5/2.0, 3.2/2.5 and 2.8/2.4 for the radial, central and ulnar portion of the TFC on its proximal side, and 2.7/2.0, 3.1/2.3 and 2.9/2.4 for the radial, central and ulnar portion on its distal side (n=15). Paired Student's t-test showed no significant difference between MSCT-AG and MR-AG (P>0.05). In a first, small series, depiction of the TFC with MSCT-AG is comparable to that of MR-AG. Further evaluation of direct multi-slice CT arthrography of the wrist in a larger patient population would be promising. (orig.)

  15. Experimental measurement of the scatter fraction in skull and body CT for teams 64- slice computed tomography; Medida experimental de la fraccion de dispersion TC en craneo y cuerpo para equipo de tomografia computarizada de 64 cortes

    Sanchez, G.; Haro, G.; Herrador, M.

    2011-07-01

    Different formalisms for the calculation of shielding in Cf equipment, the proposed document 147 of NCRP are widely accepted. Of the three methods mentioned in the protocol, two involve the use of two independent factor a of equipment, called scatter fraction CT in skull and body. Interestingly, the experimental measurement of the same, especially in those models following the publication of the document, which are also coincides with the highest number of detector channels and overall a greater radiation beam in the z axis.

  16. 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

    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

  17. Clinical Value of 64-slice Three-dimensional Computed Tomographic Angiography to Diagnosis of Intracranial Aneurysms%3D-CTA在颅内动脉瘤诊断中的临床应用价值

    王龙; 陈谦学; 田道锋; 晏炳元; 徐海涛; 吴立权; 陈伟

    2009-01-01

    目的 探讨64排三维CT血管造影(3D-CTA)在以蛛网膜下腔出血(SAH)为主要表现的颅内动脉瘤(ICAs)诊断中的临床应用价值.方法 回顾性分析181例SAH患者资料,其中3D-CTA及DSA影像学资料由一位神经外科医师和-位放射或介入科医师按双肓原则分析.最终以DSA及手术资料对3D-CTA在ICAs诊断中的临床应用价值进行评价.结果 181例SAH患者.3D-CTA共发现143例共166个动脉瘤,DSA及手术证实动脉瘤144例共170个.3D-CTA对SAH患者中动脉瘤的检出率为97.6%,对直径小于2 mm的动脉瘤检出率为66.7%,对直径大于2 mm的动脉瘤检出率接近100%.此外,3D-CTA还可清晰确切显示瘤体、瘤颈、载瘤动脉与周围组织的关系.结论 64排3D-CTA对SAH患者动脉瘤的诊断具有敏感、快捷、无创、经济等优点,与DSA有机结合有助于指导ICAs的诊断及治疗.

  18. Preliminary study of the optimization of abdominal CT scanning parameters on 64-slice spiral CT%64层螺旋CT腹部扫描参数优化的初步研究

    胡敏霞; 赵心明; 宋俊峰; 周纯武; 赵红枫

    2011-01-01

    Objective To investigate the appropriate low tube current of abdominal CT on a 64-slice spiral CT. Methods (1) Phantom study:The phantom Catphan500R was scanned with a fixed 120 kVp,and 450,400,380,360,340,320,300,280 mA, respectively. 15, 9, 8, 7, 6 mm diameter low-contrast objects with 1% contrast were scanned for evaluating image quality. CT images were graded in terms of lowcontrast conspicuity by using a five-point scale. Statistical analyses were performed to determine the appropriate tube current and the interval leading to the qualitative change. (2) Clinical study: 3 groups of 45 patients who had 2 examinations of non-enhanced abdominal CT within 3 months were enrolled. All patients were scanned with 450 mA at first scanning. For the second scanning, group-1 was scanned with optimal tube current, group-2 was scanned with optimal tube current plus interval, group-3 was scanned with optimal tube current sinus interval. CT images were graded in terms of the diagnostic acceptability at three anatomic levels including porta hepatis, pancreas and the upper pole kidney, and the image noises of eight organs including abdominal aorta, portal vein, liver, spleen, gallbladder, pancreas, renal cortex, renal medulla were graded by using a five-point scale. The image quality was compared with non-parametric rank sum test,and the individual factors of the patients were compared with the A VONA. Results (1) The optimal tube current and interval leading to the qualitative change were 340 mA and 40 mA respectively. (2) There were no significant differences in image quality between 340 mA and 450 mA in group-1, between 380 mA and 450 mA in group-2 (P > 0. 05). There was significant difference in image quality between 300 mA and 450 mA in group-3 (the mean scores for 300 mA were 2. 92 ± 0. 62,2.92 ± 0. 62,2.64 ± 0. 84,2. 72 ±0.82,2.63 ±0.71,2.51 ±0.84,3.04 ±0.72,3.04 ±0.72,2.63 ±0.71,2.52 ±0.73,2.93 ±0.81respectively; for 450 mA were 3.93 ± 0. 72,3.94 ± 0. 72

  19. 64层螺旋CT评价膝关节创伤后的隐匿病变及软组织损伤%Evaluation of the occult lesions and soft tissue injury after knee injury by 64-slice spiral CT

    钟俊; 杨法宝; 赵学航; 张丽; 李勤祥

    2012-01-01

    背景:膝关节创伤患者在行X射线检查后进一步选择64层螺旋CT检查时,根据伤情及重建需要选择何种后处理技术在临床上存在一定分歧.目的:探讨64层螺旋CT及后处理技术在膝关节创伤中的应用价值.方法:回顾性分析79例膝关节创伤患者的普通X射线片及64排螺旋CT影像学资料,采用多平面重组、容积显示和表面遮盖显示等后处理技术,结合原始骨窗及软组织窗图像,由2名以上有经验的放射科和骨科医生对图像进行双盲分析并与临床及图像重建结果对照.结果与结论:在79例膝关节创伤患者中,共计92处骨折.普通X射线片诊断68例82处骨折,1例假阳性,5例假阴性,检出率约为89%;经64层螺旋CT及三维重建后确诊79例共92处骨折,检出率100%.证实,和X射线检查相比,64层螺旋CT及多种图像重建是膝关节创伤的重要辅助检查手段,能进一步明确有无膝关节周围隐匿性骨折、微骨折及脱位及软组织损伤等.%BACKGROUND: The patients with knee trauma received the 64-slice spiral CT examination after the X-ray examination, and there still some differences on the choice of the post-processing technology in clinic according to the injury and reconstruction needs. OBJECTIVE: To investigate application value of 64-slice spiral CT and the post-processing technology in the knee injury. METHODS: The imaging data of the X-ray and 64-slice spiral CTofthe 79 patients with knee injury were retrospectively analyzed, the post-processing technology, such as the multiple planar reformation, volume rendering and shaded surface display were adopted and combined with the image of the original bone and soft tissue window, and the images were dealt by two or more experienced X-ray and orthopaedic surgeons with double-blind analysis and compared with the clinical and operation results . RESULTS AND CONCLUSION: In all the 79 patients with knee injury, there were a total of 92 fractures

  20. Establishing models of portal vein occlusion and evaluating value of multi-slice CT in hepatic VX2 tumor in rabbits

    Yue-Yong Qi; Li-Guang Zou; Ping Liang; Dong Zhang

    2007-01-01

    AIM: To establish models of portal vein occlusion of hepatic VX2 tumor in rabbits and to evaluate the value of multi-slice CT.METHODS: Forty New Zealand rabbits were divided into 4 groups according to digital table: Immediate group (group A; transplantation of tumor immediately after the portal vein occlusion), 3-wk group (group B;transplantation of tumor at 3 wk after the portal vein occlusion), negative control group (group C) and positive control group (group D), 10 rabbits in each group.Hepatic VX2 tumor was transplanted with abdominal-embedding innoculation immediately after the portal vein occlusion and at 3 wk after the portal vein occlusion.Meanwhile, they were divided into negative control group (Left external branch of portal vein was occluded by sham-operation, and left exite was embedded and inoculated pseudoly) and positive control group (Transplanted tumor did not suffer from the portal vein occlusion). All rabbits were scanned with multi-slice CT.RESULTS: All 40 animals were employed in the final analysis without death. Tumor did not grow in both immediate group and 3-wk group. In 3-wk group, left endite was atrophied and growth of tumor was inhibited.The maximal diameter of tumor was significantly smaller than that in positive control group (2.55 ± 0.46 vs3.59 ± 0.37 cm, t = 5.57, P < 0.001). Incidences of metastasis in the liver and lung were lower in 3-wk group than those in positive control group (10% vs 40%, and 90% vs 100%, respectively). The expression intensities of the vascular endothelium growth factor (VEGF) in groups A, B, C and D were 0.10 ± 0.06, 0.66 ± 0.21, 0.28± 0.09 and 1.48 ± 0.32, respectively. VEGF expression level in the test group A was significantly lower than that in the negative control group C (t = 5.07; P < 0.001).In addition, VEGF expression in the test group B was significantly lower than that in the positive control group D (t = 6.38; P < 0.001). Scanning with multi-slice CT showed that displaying rate of

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

    Behroozi, Hamid; Davoodi, Mohammad; Aghasi, Shahriar

    2015-01-01

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

  2. Rapid assessment of myocardial infarct size in rodents using multi-slice inversion recovery late gadolinium enhancement CMR at 9.4T

    Hausenloy Derek J

    2011-09-01

    Full Text Available Abstract Background Myocardial infarction (MI can be readily assessed using late gadolinium enhancement (LGE cardiovascular magnetic resonance (CMR. Inversion recovery (IR sequences provide the highest contrast between enhanced infarct areas and healthy myocardium. Applying such methods to small animals is challenging due to rapid respiratory and cardiac rates relative to T1 relaxation. Methods Here we present a fast and robust protocol for assessing LGE in small animals using a multi-slice IR gradient echo sequence for efficient assessment of LGE. An additional Look-Locker sequence was used to assess the optimum inversion point on an individual basis and to determine most appropriate gating points for both rat and mouse. The technique was applied to two preclinical scenarios: i an acute (2 hour reperfused model of MI in rats and ii mice 2 days following non-reperfused MI. Results LGE images from all animals revealed clear areas of enhancement allowing for easy volume segmentation. Typical inversion times required to null healthy myocardium in rats were between 300-450 ms equivalent to 2-3 R-waves and ~330 ms in mice, typically 3 R-waves following inversion. Data from rats was also validated against triphenyltetrazolium chloride staining and revealed close agreement for infarct size. Conclusion The LGE protocol presented provides a reliable method for acquiring images of high contrast and quality without excessive scan times, enabling higher throughput in experimental studies requiring reliable assessment of MI.

  3. The clinical value of combined use of MR imaging and multi-slice spiral CT in limb salvage surgery for orthopaedic oncology patients: initial experience in nine patients

    The purpose of this prospective study was to evaluate the value of the combined use of MR imaging and multi-slice spiral CT for limb salvage surgery in orthopaedic oncology patients. Nine consecutive patients with lower/upper limb malignant bone tumours (7 osteosarcomas and 2 chondrosarcomas) were treated with limb-salvaging procedures. Preoperative planning including determination of the osteotomy plane and diameters of the prosthesis was performed basing on the preoperative CT and MR images. The histopathology was performed as golden diagnostic criteria to evaluate the accuracy of CT and MR-based determination for tumour’s boundary. The tumour extension measured on MRI was consistent with the actual extension (P>0.05, paired Student’s t test), while the extension measured on CT imaging was less than the actual extension. The length, offset and alignment of the affected limb were reconstructed accurately after the operation. An excellent functional outcome was achieved in all patients. In the present study, MRI was found to be superior to CT for determining the tumour extension, combined use of MRI and CT measurement provided high precision for the fit of the prosthesis and excellent functional results

  4. Diagnostic Accuracy of Sixty Four Multi-Slice CT Angiography in Assessment of Arterial Cut-Off and Run-Off in Comparison with Surgical Findings

    M. Noaparast

    2011-06-01

    Full Text Available Background/Objective: The accurate anatomic mapping and determination of the severity of arterial disease, an important health problem of the elderly, is of great significance. We aimed todetermine the diagnostic value of 64-multislice CT angiography (MSCTA in run-off and cut-off sites of arterial disease.Patients and Methods: Throughout the study, MSCTA followed by an operative intervention was carried out on a total of 38 patients with clinical signs and symptoms suggestive of arterialdisease (AD all of whom had the indication for vascular surgery. The mean age of patients was 34±15.86 (range, 23 to 93 years. MSCTA was executed using a 64-slice CT scanner, during the arterial phase of injecting the nonionic, contrast medium with a power injector at the rate of 5 ml/sec into the antecubital vein and exploration and revascularization of peripheral arterial disease was performed intraoperatively.Results: Atherosclerosis and arterial disease, the most common causes of vascular occlusion,were more common in the lower extremities. According to MSCTA findings, the most frequentsite of stenosis was the superficial femoral artery. Spearman’s correlation coefficient showed a high degree of agreement amongst the raters. The sensitivity, specificity, positive predictivevalue (PPV, negative predictive value (NPV and the accuracy of MSCTA compared to surgery were 83.8%, 96%, 96.8%, 81.3% and 89%, respectively. MSCTA findings were compared with surgeryas a standard of reference, which showed concordance in the majority of cases (81.6%. Cut-off sites were correctly identified by MSCTA in 97.3% of the patients and the most common sites of discordance were the run-off sites (18.2%.Conclusion: MSCTA angiography as a novel diagnostic modality may be a suitable alternative and a viable choice for routine clinical diagnosis.

  5. Diagnostic accuracy of sixty four multi-slice CT angiography in assessment of arterial cut-off and run-off in comparison with surgical findings

    The accurate anatomic mapping and determination of the severity of arterial disease, an important health problem of the elderly, is of great significance. We aimed to determine the diagnostic value of 64-multislice CT angiography in run-off and cut-off sites of arterial disease. Patients and Methods: Throughout the study, multislice CT angiography followed by an operative intervention was carried out on a total of 38 patients with clinical signs and symptoms suggestive of arterial disease all of whom had the indication for vascular surgery. The mean age of patients was 34±15.86 (range, 23 to 93) years. Multislice CT angiography was executed using a 64-slice CT scanner, during the arterial phase of injecting the nonionic, contrast medium with a power injector at the rate of 5 ml/sec into the antecubital vein and exploration and revascularization of peripheral arterial disease was performed intraoperatively. Results: Atherosclerosis and arterial disease, the most common causes of vascular occlusion, were more common in the lower extremities. According to multislice CT angiography findings, the most frequent site of stenosis was the superficial femoral artery. Spear man's correlation coefficient showed a high degree of agreement amongst the raters. The sensitivity, specificity, positive predictive value, negative predictive value and the accuracy of multislice CT angiography compared to surgery were 83.8%, 96%, 96.8%, 81.3% and 89%, respectively. Multislice CT angiography findings were compared with surgery as a standard of reference, which showed concordance in the majority of cases (81.6%). Cut-off sites were correctly identified by multislice CT angiography in 97.3% of the patients and the most common sites of discordance were the run-off sites (18.2%). Conclusion: multislice CT angiography angiography as a novel diagnostic modality may be a suitable alternative and a viable choice for routine clinical diagnosis.

  6. Automated quantification of cardiac short-axis multi-slice CT images for assessment of left ventricular global function

    Danilouchkine, Mikhail G.; Admiraal-Behloul, Faiza; van der Geest, Rob J.; Lelieveldt, Boudewijn P. F.; Reiber, Johan H. C.

    2005-04-01

    This paper describes a method for automatic contour detection in reformatted short-axis (SA) cardiac computed tomography (CT) using a virtual exploring robot. The robot is a tricycle with a steering front wheel. Its motion obeys a set of kinematic equations and is subject to the non-holonomic constraints. The robot is designed to navigate in the binary representation of a cardiac image, consisting of the allowed navigational and obstacle spaces. It is initially positioned inside the allowed navigational space. Avoiding obstacles, the robot autonomously cruises through the navigational space and collects information about the location of the left ventricular (LV) boundaries. Consequently, the obtained information is used to reconstruct the endocardial and epicardial contours. Validation of the method was performed on in-vivo multislice multiphase short-axis cardiac CT images of ten subjects. Results showed good correlation between the quantitative parameters, computed from manual and automatic segmentation: for end-diastolic volume (EDV) r=0.99, for end-systolic volume (ESV) r=0.98, ejection fraction (EF) r=0.83, and LV mass (LVM) r=0.95.

  7. Ex-vivo injection technique for implanting solid pulmonary nodules into porcine lungs for multi-slice CT

    Purpose: To develop a method for generating realistic pulmonary nodules that equal small pulmonary metastases and granulomas. Materials and Methods: A total of 70 artificial lesions were introduced into 5 inflated porcine lungs inside a dedicated chest phantom by high pressure injection of a fat-wax-Lipiodol mixture and scanned with 16-slice computed tomography (CT). Image evaluation by two experienced radiologists included analysis of morphology, nodule size and density. Results: The median nodule density was 78.8 Hounsfield units (HU), with 54 of 70 nodules (77.14%) judged typical of small lung metastases. Conclusion: Without inducing visible damage of lung parenchyma, the injection technique produces highly realistic pulmonary nodules for morphometry or nodule detection with CT. (orig.)

  8. 卵巢囊性畸胎瘤B超及多排螺旋CT的诊断价值比较%Comparison of the diagnostic value of ovarian cystic teratoma B ultrasound and multi-slice spiral CT

    樊兆丽; 彭明洋

    2015-01-01

    Objective To investigate the diagnosis of ovarian cystic teratoma of B ultrasound and multi-slice spiral CT. Methods A retrospective analysis of 40 patients with surgically and pathologically confirmed ovarian cystic teratoma B ultrasound and CT image data.Results Multi-slice spiral CT diagnosis is higher than B ultrasound. Conclusion B ultrasound for routine screening, joint multi-slice spiral CT can improve diagnosis of ovarian cystic teratoma.%目的:探讨卵巢囊性畸胎瘤的B超及多排螺旋CT的诊断价值。方法:回顾性分析40例经手术及病理证实的卵巢囊性畸胎瘤的B超及CT影像资料。结果:多排螺旋CT的诊断符合率高于B超。结论:B超检查适用于常规筛选检查,联合多排螺旋CT检查,可提高卵巢囊性畸胎瘤的定性诊断。

  9. Comparison of multi-slice CT (MSCT) and TI-201 myocardial SPECT in detection of coronary artery disease: relation to coronary arteriography

    To evaluate the diagnostic potentials of MSCT and TI-201 SPECT in the assessment of coronary artery disease. Twenty-four patients (15 men, 9 women, 42-79 years) with clinically suspected coronary artery disease were studied by TI-201 myocardial SPECT and MSCT. MSCT data were obtained with 12 x 0.75 mm, 420ms rotation, multi-slice CT scanner (SOMATOM Sensation, Siemens) using non-ionic contrast, 80ml, 4ml/sec. Multiplanar reconstruction techniques were used for evaluation of coronary arteries. TI-201 myocardial SPECT were performed at stress with adenosine and at rest. Data from MSCT and TI-201 SPECT were compared territory by territory (divided into two segments; LAD and RCA/LCx) and related to coronary arteriography, in which more than 60% stenoses are regarded as significant. MSCT and TI-201 SPECT showed agreement in 37 out of 48 segments (77.1%). Out of 11 disagreed segments (22.9), TI-201 SPECT was superior in 6 segments and MSCT was superior in 5 segments. Sensitivities and specificities of MSCT and TI-201 SPECT by coronary arteriography are 81.8%, 69.2% and 86.3%, 76.9%, respectively. Agreed 4 segments between MSCT and TI-201 SPECT exhibited results that differ from the results of coronary arteriography. Myocardial bridge in two cases were detected as significant stenoses by MSCT but showed normal perfusion in TI-201 SPECT. Agreement between MSCT and TI-201 SPECT in the assessment of coronary artery disease was good but TI-201 SPECT has higher sensitivity and specificity for the detection of jeopardized myocardium than MSCT. MSCT and TI-201 SPECT provide complementary information in the assessment of coronary artery disease and could help reduce probable mistake in the interpretation of hemo dynamically insignificant lesion in coronary arteriography

  10. Multi-slice abdominal CT in oncological patients. Influence of table feed and detector configuration on image quality and radiation exposure

    Purpose: To evaluate the image quality and radiation exposure of different spiral CT scanning parameters for routine staging examination of the abdomen in oncologic patients using a multi-slice CT scanner. Methods/Materials: Examination of 40 patients in 4 groups on a multislice CT scanner (Somatom VolumeZoom, Siemens AG, Forchheim). Functional detector width (4x2.5, 4x5 mm) and pitch (table feed in relation to collimated slice width) were varied (3 and 5). Tube voltage (120 kV), effective tube current (160 mAs), slice-thickness (6 mm), increment (4 mm), kernel (B 30), and contrast injection parameters were dept constant. Axial images were assessed by three radiologists regarding delineation of anatomic structures, artifacts, and overall image quality. Results: Significantly reduced image quality especially due to artifacts was observed using a 5 mm detector configuration with a pitch of 5 (scan time 9 sec). Image quality was rated best for a 2.5 mm detector configuration with a pitch of 3 and a scan time of 28 sec. The effective dose was independent of the pitch. However, the mean effective dose was 9% higher using the smaller detector configuration (9.9 mSv vs 10.9 mSv). Conclusions: For routine staging CT of the abdomen use of a 4x2.5 mm detector configuration with a pitch between 3 and 5 is recommended. A 4x5 mm detector configuration using overlapping data acquisition can also be recommended, but additional thin slice reformations are not possible. (orig.)

  11. Accelerated magnetic resonance diffusion tensor imaging of the median nerve using simultaneous multi-slice echo planar imaging with blipped CAIPIRINHA

    Filli, Lukas; Kenkel, David; Boss, Andreas; Manoliu, Andrei; Andreisek, Gustav; Runge, Val M.; Guggenberger, Roman [University Hospital of Zurich, University of Zurich, Institute of Diagnostic and Interventional Radiology, Zurich (Switzerland); Piccirelli, Marco [University Hospital of Zurich, Department of Neuroradiology, Zurich (Switzerland); Bhat, Himanshu [Siemens Medical Solutions USA Inc, Charlestown, MA (United States)

    2016-06-15

    To investigate the feasibility of MR diffusion tensor imaging (DTI) of the median nerve using simultaneous multi-slice echo planar imaging (EPI) with blipped CAIPIRINHA. After federal ethics board approval, MR imaging of the median nerves of eight healthy volunteers (mean age, 29.4 years; range, 25-32) was performed at 3 T using a 16-channel hand/wrist coil. An EPI sequence (b-value, 1,000 s/mm{sup 2}; 20 gradient directions) was acquired without acceleration as well as with twofold and threefold slice acceleration. Fractional anisotropy (FA), mean diffusivity (MD) and quality of nerve tractography (number of tracks, average track length, track homogeneity, anatomical accuracy) were compared between the acquisitions using multivariate ANOVA and the Kruskal-Wallis test. Acquisition time was 6:08 min for standard DTI, 3:38 min for twofold and 2:31 min for threefold acceleration. No differences were found regarding FA (standard DTI: 0.620 ± 0.058; twofold acceleration: 0.642 ± 0.058; threefold acceleration: 0.644 ± 0.061; p ≥ 0.217) and MD (standard DTI: 1.076 ± 0.080 mm{sup 2}/s; twofold acceleration: 1.016 ± 0.123 mm{sup 2}/s; threefold acceleration: 0.979 ± 0.153 mm{sup 2}/s; p ≥ 0.074). Twofold acceleration yielded similar tractography quality compared to standard DTI (p > 0.05). With threefold acceleration, however, average track length and track homogeneity decreased (p = 0.004-0.021). Accelerated DTI of the median nerve is feasible. Twofold acceleration yields similar results to standard DTI. (orig.)

  12. A comparative study for spatial resolution and subjective image characteristics of a multi-slice CT and a cone-beam CT for dental use

    Purpose: Multi-slice CT (MSCT) and cone-beam CT (CBCT) are widely used in dental practice. This study compared the spatial resolution of these CT systems to elucidate which CT modalities should be selected for various clinical cases. Materials and methods: As MSCT and CBCT apparatuses, Somatom Sensation 64 and 3D Accuitomo instruments, respectively, were used. As an objective evaluation of spatial resolution of these CT systems, modulation transfer function (MTF) analysis was performed employing an over-sampling method. The results of MTF analysis were confirmed with a line-pair test using CATPHAN. As a subjective evaluation, a microstructure visualization ability study was performed using a Jcl:SD rat and a head CT phantom. Results: MTF analysis showed that for the in-plane direction, the z-axis ultrahigh resolution mode (zUHR) of the Sensation 64 and 3D Accuitomo instruments had higher spatial resolutions than the conventional mode (64x) of the Sensation 64, but for the longitudinal direction, the 3D Accuitomo had clearly higher spatial resolution than either mode of the Sensation 64. A line-pair test study and microstructure visualization ability studies confirmed the results for MTF analysis. However, images of the rat and the CT phantom revealed that the 3D Accuitomo demonstrated the failure to visualize the soft tissues along with aliasing and beam-hardening artifacts, which were not observed in the Sensation 64. Conclusions: This study successfully applied spatial resolution analysis using MSCT and CBCT systems in a comparative manner. These findings could help in deciding which CT modality should be selected for various clinical cases.

  13. 64-multislice detector computed tomography coronary angiography as potential alternative to conventional coronary angiography: a systematic review and meta-analysis

    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...

  14. Multi-slice spiral CT reconstruction in the diagnosis tracheal bronchus%多排螺旋CT重建技术诊断气管性支气管

    童三龙; 邓宏亮; 张凯; 王新正

    2014-01-01

    目的:探讨多排螺旋CT(MSCT)对气管性支气管的诊断及应用价值,认识先天性气管性支气管的临床意义。方法分析5例气管性支气管(TB)患者的MSCT薄层图像及多平面重组(MPR)、最小密度投影(MinIP)、容积再现(VR)及支气管虚拟内镜(VB)等多种后处理图像。结果5例气管性支气管均为右肺上叶尖段支气管发生在气管及右主支气管的右侧壁或右后壁,经多种后处理,均能清晰地显示气管性支气管的起源部位,有无狭窄及其他合并症情况。结论 MSCT无创、操作简单,可作为气管性支气管诊断的首选检查方法。%Objective To investigate the value of diagnosis and application in multi-slice spiral CT (MSCT) for diagnosing tracheal bronchus (TB), and recognize the clinical significance of tracheal bronchus(TB). Methods Ana-lyze the original and reconstructed MSCT images of 5 patients with TB, the reconstruction techniques included multi-planar reconstruction (MPR), minimum intensity projection (MinIP), volume rendering (VR), virtual bronchoscopy (VB). Results Five cases of tracheal bronchus occurred in the trachea or right main bronchus of the right side wall or the right posterior wall. Initiation site, stenosis, other complications of TB can be clearly displayed by various 3D recon-struction technology. Conclusion As a noninvasive and simple examination methods, MSCT should be the first choice in diagnosing TB.

  15. Evaluation of changes in the parameters of brain tissue perfusion in multi-slice computed tomography in patients after carotid artery stenting

    CT perfusion of the brain allows functional evaluation of cerebral blood flow. Patients with chronic internal carotid artery (ICA) stenosis may suffer from malperfusion. Improvement of cerebral blood flow and remission of neurological symptoms indicate the effectiveness of treatment of internal carotid artery stenosis. Material/Methods: The aim of the study was to analyze alterations within cerebral perfusion parameters in CT brain perfusion examination in patients who were scheduled for endovascular therapy due to ICA stenosis. Forty patients with ICA stenosis of over 79% who were included in this prospective study underwent perfusion CT examination twice - 24 hours prior to stenting and after 6-8 weeks following the procedure. CBF, CBV, MTT and TTP were evaluated. Results: Prior to endovascular therapy, an increase in MTT and TTP, and a decrease in CBV and CBF were observed within arterial supply of the hemisphere ipsilateral to stenosis. After the procedure, a decrease in MTT and TTP was seen in all cases, while no statistically significant changes of CBF or CBV were observed. MTT proved to be the most sensitive indicator of ICA stenosis, as its values allowed differentiation between critical and non-critical stenosis. No correlation between the degree of ICA stenosis and TTP values was found. Mild cerebral hyperperfusion syndrome (CHS) was observed in only one patient and the difference between pre-treatment MTT values calculated for both hemispheres was shown to be a prognostic factor for CHS incidence. Conclusions: Endovascular stent placing in patients with hemodynamically significant internal carotid artery stenosis results in alteration of perfusion parameters, especially concerning TTP and MTT. (authors)

  16. Genetic association of glutathione peroxidase-1 with coronary artery calcification in type 2 diabetes: a case control study with multi-slice computed tomography

    Fujimoto Kei; Nishioka Makiko; Miyashita Yumi; Hiki Yoshito; Sasaki Takashi; Nishimura Rimei; Nemoto Masami; Sakuma Toru; Ohashi Toya; Fukuda Kunihiko; Eto Yoshikatsu; Tajima Naoko

    2007-01-01

    Abstract Background Although oxidative stress by accumulation of reactive oxygen species (ROS) in diabetes has become evident, it remains unclear what genes, involved in redox balance, would determine susceptibility for development of atherosclerosis in diabetes. This study evaluated the effect of genetic polymorphism of enzymes producing or responsible for reducing ROS on coronary artery calcification in type 2 diabetes (T2D). Methods An index for coronary-arteriosclerosis, coronary artery c...

  17. MSCT重组技术对气管破裂的诊断价值%Multi-slice CT and advanced reconstruction techniques in the diagnosis of tracheal rupture

    杨鸿; 杨文; 蒋洪春; 彭湘晖; 曹林德

    2012-01-01

    Objective:To assess the value of multi slice CT (MSCT) with reconstruction techniques in the diagnosis of tracheal rupture. Methods: 128 slice spiral CT (MSCT) scanning was performed in 7 patients with tracheal rupture caused by severe trauma to the neck and thorax,iatrogenic injury and spontaneous tracheal rupture. The images of multipla nar reconstruction (MPR) ,CT virtual endoscopy (CTVE) were obtained on a postprocessing workstation. Results: CT ap pearances of tracheal rupture included defect in trachea with deep cervical air or air tracking into the mediastinum. MPR clearly displayed the shape and size of tracheal defect,the distances between the tracheal defect to some important anatomic landmarks such as tracheal carina, epiglottis and superior border of the manubrium. CTVE showed the tracheal defects in the 5 patients with trauma to the neck and thorax and spontaneous tracheal ruptures. However,the image of CTVE was a little blurred than MPR. Color coded volume rendered images provided realistic 3D views of air leak distribution of the tra cheal rupture. Conclusion: MSCT with reconstruction techniques play an important role in the diagnosis and treatment of tra cheal rupture.%目的:探讨MSCT重组技术对气管破裂的诊断及临床应用价值.方法:回顾性分析7例气管破裂患者的CT资料,病因分别为颈胸部严重外伤、医源性损伤、自发性因素.采用128层螺旋CT对7例患者行颈胸部平扫,原始数据行减薄重组,将减薄重组后的图像传输到工作站进行多平面重组及CT仿真内窥镜(CTVE)观察.结果:气管破口以及溢出的气体均表现为低密度影,气管壁连续性中断,MPR重组可以完整显示破裂口形态和大小、距气管隆突、会厌或胸骨柄上缘等重要解剖标志的距离;2例严重患者在双侧颜面部、颈部、颞下窝、咽旁组织间隙、前后胸壁皮下、纵隔内均有广泛分布的低密度气影;最轻的1例仅见裂口附近的后纵隔内

  18. Müller状态下64排螺旋CT对阻塞性睡眠呼吸暂停低通气综合征诊断价值的研究%The study of the diagnostic value of 64-slice CT in obstructive sleep apnea hypopnea syndrome in Müller mameuver

    周旭; 王建中; 刘骏桢

    2013-01-01

    目的:通过对平静呼吸和Müller状态下的中重度OSAHS患者行CT扫描,了解Müller状态下上气道阻塞塌陷的具体部位、程度及累及范围,为手术治疗提供依据.方法:对30例经PSG确诊的中重度OSAHS患者分别行平静呼吸和Müller状态下64排VCT扫描,并经上气道三维重建和仿真内镜技术处理,比较2种状态下上气道各平面横截面积和各径线长度以及咽壁厚度、软腭悬雍垂长厚度、软硬腭角度、舌骨硬腭距离等指标.结果:平静呼吸时吸气末和Müller's动作吸气末各平面截面积和径线比较,舌根后区及会厌后区的前后径差异无统计学意义(P>0.05),其余所有气道径线的差异均有统计学意义(P<0.05).各平面软组织厚度比较,软腭后区、悬雍垂后区、舌根后区左右侧壁软组织厚度及软腭后区的后壁厚度、悬雍垂软腭长厚度比较差异均有统计学意义(P<0.05),软硬腭角度比较差异有统计学意义(P<0.05),舌骨的位置在Müller' s动作时有显著的下移.结论:通过64排CT上气道三维重建和仿真内镜技术,可推测中重度OSAHS患者打鼾时上气道塌陷阻塞的具体部位、程度、累及范围,以及上气道各平面软组织的变化情况,其临床应用价值大.%Objective:To examine the location,extent and cause of collapsed airway in Muller maneuver in OS-AHS patients with CT scan,and provide the evidence for surgery. Method:Thirty patients with moderate or severe OSAHS were measured with 64 slice CT in quiet breathing and in Muller maneuver. After three-dimensional reconstruction and virtual endoscope handing of the upper airway, we compare the cross-section area and the dimensions of five levels as well as the thickness of retropharyngeal and lateral pharyngeal tissue in two conditions. The evaluation values include the length and thickness of soft palate and uvula, soft-hard palate angle and hyoid hard palate distance. Result:The lateral distance

  19. Study on the three dimensional hepatic virtual operation based on the data of 64-slice helical CT scanning%基于64排螺旋CT扫描数据三维肝脏手术仿真的研究

    朱新勇; 方驰华; 鲍苏苏; 全显跃; 焦培峰; 钟世镇

    2008-01-01

    目的 研究基于64排螺旋CT扫描数据的三维肝脏虚拟手术的设计和仿真效果,以及基于自由设计模型系统(FreeForm Modeling System)的虚拟手术的可行性.方法 采集正常人肝脏64排薄层扫描数据集,利用医学三维重建软件(MIMICS软件)进行肝脏及其肝内血管三维重建,并将重建的肝脏及其管道模型、人工绘制肝脏肿瘤模拟物导入FreeForm Modeling System,利用力反馈设备(PHANToM),对肝脏模型进行手术切割.结果 通过旋转和放大目标物体,肿瘤与肝内血管的立体关系能清晰展示.根据手术原则,使用PHANToM操纵"手术刀",仿真左外叶切除,术中肝内管道结构容易识别,其过程基本符合临床肝脏肿瘤切除的手术过程并可调节目标物体的强度,感受切割时力反馈的大小.结论 利用FreeForm Modeling System虚拟手术系统仿真肝脏手术切割,可以制定合理的个体化手术方案,减少并发症发生,提高手术成功率.%Objective To study the surgery plan and simulation effect of the three dimensional(3D)hepatic virtual operation based on the data of 64-slice helical CT scanning and to probe the feasibility of the virtual operation based on the FreeFotin Modeling System.Methods The volunteer liver Was scanned to collect two dimensional(2D)DICOM data of 64-slice helical CT scanning and the 3D hepatic and intrahepatic vessels model were reconstructed by MIMICS software.The reconstructed liver,the intrahepatic vessels model and the artificial tumor models were outputted into the FreeForm Modeling System in the STL format.The device PHANToM with the characterization of dynamo-feedback was applied to make the operation on tlle 3D hepatic.Resuits The spatial relationship between the tumour and the intrahepatic vessels were clearly observed by rotation and enlargement of the target.According to the operation principle,the left lobe of liver resection was simulated by manipulating the device PHANToM.Through the

  20. 多层螺旋CT与核磁共振成像联合诊断腕关节损伤的探析%Multi-slice spiral CT combined with magnetic resonance imaging in diagnose of wrist joint injury

    郭侨阁; 王顺利; 牛军杰; 刘彦; 唐楠; 周龙

    2015-01-01

    Objective To explore significance of multi-slice spiral CT combined with magnetic resonance imaging in the diagnose of wrist joint injury.Methods 168 patients with wrist joint injury admitted into our hospital from January,2012 to September,2014 were investigated.Their clinical data were analyzed.According the different examination methods,the patients were randomly divided into three groups,56 cases for each group.These 3 groups were given multi-slice spiral CT examination,magnetic resonance imaging examination,and multi-slice spiral CT combined with magnetic resonance imaging examination,respectively.The diagnosis situations and the advantages of different examination methods of the three groups were analyzed.Results The detection rate of multi-slice spiral CT was 73.21%,that of magnetic resonance imaging 75.00%,and that of the combination group 96.43%.The statistical analysis showed that there were no significant differences (P> 0.05).However,the detection rate of the combination group was significantly higher than those multi-slice spiral CT and magnetic resonance imaging (P <0.05);The detection rate of the combination of multi-slice spiral CT and magnetic resonance imaging was significantly higher than that of just one of these two examination methods(P <0.05).Conclusions Multi-slice spiral CT combined with magnetic resonance imaging in the diagnosis of wrist joint injury is most effective.It synthesizes the advantages of the two examination methods,improves the detection rate,and makes the specific injury situation clear.It's worth being clinically generalized.%目的 探究采用多层螺旋CT与核磁共振成像联合诊断腕关节损伤的情况.方法 调查研究我院在2012年1月至2014年9月间收治的168例腕关节损伤患者,分析其临床资料,根据检查方法的不同,将本组患者随机分成三组,各56例,分别给予多层螺旋CT检查、核磁共振成像检查和多层螺旋CT联合核磁共振成像检查.分析

  1. 64排螺旋CT冠状动脉成像与冠状动脉造影对心肌桥诊断的比较研究%Diagnosis Comparison of Myocardial Bridge by 64-slice CT Coronary Angiography and Conventional Coronary Angiography

    施斌斌; 吴晶涛; 征锦; 叶靖; 王守安

    2012-01-01

    目的:比较64排螺旋CT冠状动脉成像(64 SCTCA)和冠状动脉造影(CAG)对心肌桥(MB)的诊断价值.方法:832例患者分别行64SCTCA扫描及CAG,观察有无MB及测量MB的长度、厚度、壁冠状动脉(MCA)狭窄程度等,并对结果进行对比研究.结果:64 SCTCA MB检出率为18.3%,CAG MB检出率为10.2%,两者比较差异有统计学意义(P<0.05).64 SCTCA与CAG对MB的狭窄程度及长度比较,差异也有统计学意义(P<0.05).结论:与CAG相比,64SCTCA对MB有较高的检出率,并能准确显示壁冠状动脉与心肌的解剖关系.%Objective To compare the clinical significance of 64-slice coronary CT angiography(64 SCTA) and conventional coronary angiography(CAG) for identification of myocardial bridge. Methods Eight hundred and thirty —two patients with suspected coronary artery disease underwent multi-detector row CT and conventional coronary angiography respectively.The prevalence, precise location, length, depth and concomitant atheromatous changes were evaluated. Results One hundred and sixty-five sites of MB were found in 152(18.3%, 152/832) of 832 patients with 64 SCTA, with MB detection rate of 10.2% by CAG, and the difference was statistically significant(P<0.05). There was also significant difference between 64 SCTCA and CAG for the degree and length of stenosis of the MB. Conclusion Compared with CAG, 64 SCTCA has a higher detection rate for MB, and can accurately show the relationship between mural coronary arteries and myocardial.

  2. Evaluation of aortic valve stenosis by cardiac multislice computed tomography compared with echocardiography: a systematic review and meta-analysis

    Abdulla, Jawdat; Sivertsen, Jacob Christian; Kofoed, Klaus Fuglsang;

    2009-01-01

    BACKGROUND AND AIM OF THE STUDY: It has not yet been established whether multi-slice computed tomography (MSCT) is reliable for the quantification of aortic valve area (AVA) in patients with aortic valve stenosis (AVS) and simultaneously for assessment of the coronary anatomy. The study aim, via ...

  3. 多层螺旋CT尿路成像在上尿路疾病中的应用%Application of Multi-slice Spiral CT Urography in Diagnosis of Upper Ureteric Diseases

    李建勇; 程树林; 陈双全; 朱平宇; 廖波

    2013-01-01

    目的探讨多层螺旋CT尿路成像(CTU)在上尿路疾病中的临床应用价值。方法对41例经B超或IVP检查显示上尿路疾病患者行螺旋 CT扫描,并行三维重建,将诊断与手术结果进行对照。结果41例中输尿管狭窄20例,肾盂及输尿管肿瘤10例,输尿管结石8例,结核3例。CTU均立体直观地显示病变形态及其与周围组织的关系,诊断与最终手术结果均相符。结论 CTU是一种安全有效的非侵袭性的影像学检查方法,对上尿路疾病的诊断具有极高价值。%Objective To assess the diagnostic value of multi slice spiral CT urography (CTU) in patients with upper urinary tract diseases. Methods 41 patients with upper urinary tract diseases confirmed by B-ultrasound or IVP performed multi slice spiral CT urography (CTU) scan and the three dimensional reconstructions. The imaging findings were checked with post operative pathological findings. Results In the 41 cases , congenital stricture in ureteropelvic junction or ureterovesical orifice were found in 20 cases ,21 patients were diagnosed as pyeloureter neoplasm (10 cases) , ureter negative stone (8 cases),tuberculosis of ureter (3 cases).CTU provided high resolution images of the pelvis and ureter tract in al patients. All the cases were confirmed by operation.Conclusion CTU is a safe, highly efficient and noninvasive method, it plays important role in the diagnosis of urinary diseases.

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

    沈栋; 潘昌杰

    2011-01-01

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

  5. 多层螺旋CT对肝外梗阻性黄疸的诊断价值%Diagnostic value of multi-slice spiral CT in extrahepatic obstructive jaundice

    王小仁; 张云; 蔡顺达

    2015-01-01

    Objective To explore the diagnostic value of multi-slice spiral CT in extrahepatic obstructive jaundice.Methods MSCT findings in 12 cases ofextrahepatic obstructive jaundice confirmed by the surgery and clinic were retrospectively analyzed.Results Among 12 cases,10 cases were subjected to anhanced scanning;Among all cases,6 cases of bile duct carcinoma,3 cases of carcinoma of head of pancreas, 3 cases of bile duct stones.Conclusion CT scan can clearly without obstruction, determining the site of obstruction,further qualitative diagnosis.%目的:探讨多层螺旋CT对梗阻性黄疸的诊断价值。方法:回顾性分析由手术和临床证实的12例患者的CT资料。结果:12例患者中,10例行CT平扫加增强扫描;12例患者中胆管癌6例,胰头癌3例,胆管结石3例。结论:CT检查可明确有无梗阻的存在,确定梗阻部位,进一步行定性诊断。

  6. Comparative study on the clinical value between multi slice spiral CT urography and intravenous pyelography%多层螺旋CT尿路成像与静脉肾盂造影的临床价值对比研究

    傅其添; 林忠伟; 陈恩明

    2014-01-01

    目的:通过对比多层螺旋 CT 尿路成像(MDCTU)和静脉肾盂造影(IVP)对泌尿系统疾病检出和诊断准确率,探讨MDCTU检查对泌尿系统疾病的临床应用价值和对IVP的优良替代性。方法:2011-2013年收治泌尿系疾病患者75例,均接受MDCTU和IVP检查。比较两种检查方法对泌尿系统疾病的检出及诊断差异,并与手术病理或临床随访结果对照。结果:经手术病理或临床随访证实,共发现结石39例,肿瘤14例,炎症8例,肾囊肿8例,创伤3例,先天性畸形3例。75例患者中MDCTU和IVP检查诊断检出率分别为96%(72/75)、52%(42/75),两者差异有统计学意义(P<0.05)。结论:CTU能够提供IVP所无法具备的丰富的诊断信息,对泌尿系统疾病检出、定性、周边侵犯等方面诊断明显优于IVP,完全可代替IVP而成为临床常规检查。%Objective:By comparing the detection rate and the accurate rate of diagnosis of multi slice spiral CT urography(MDCTU) and multi-slice spiral CT imaging and urinary detection(MDCTU) and intravenous pyelography(IVP) in urinary system diseases,to explore the clinical application value and excellent alternative to IVP of MDCTU examination in urinary system disease.Results:75 cases with urinary tract diseases were selected from 2011 to 2013.They were given MDCTU and IVP examination.We compared the detection rate and the accurate rate of the two check modes,and compared it with operation and pathology or clinical follow-up results.Results:Proved by operation and pathology or clinical follow-up,39 cases were calculi;14 cases were tumor;8 cases were inflammation;8 cases were renal cysts;3 cases were trauma;3 cases were congenital malformation.In 75 cases,the detection rate of MDCTU and IVP were 96% (72/75) and 52% (42/75),and the difference was statistically significant(P<0.05).Conclusion:CTU can provide abundant diagnostic information which IVP cannot be made.The diagnosis of urinary

  7. Clinical value of multi-slice helical CT angiography in diagnosis of cerebral vascular diseases%MSCTA在脑血管性疾病诊断中的应用价值

    宁殿秀; 李智勇; 王克礼

    2006-01-01

    Objective: To evaluate the clinical value of multi-slice helical CT angiography (MSCTA) in diagnosis of cerebral vascular diseases.Methods: 52 patients with cerebral vascular diseases were examined with GE Light Speed 4-slice and 16-slice helical CT.Pitch: 0.5-3,slice thickness: 0.625-1.25 mm,adult injection dosage: 90-100 mL,children injection dosage: 2 mL/kg,injection rate: 2.5-4.0 mL/s,delay time: 15-22 s.Intelligent track scan (Smart prep Rx) were adopted in parts of these cases.Three-dimensional cerebral vascular images were processed at ADW 3.1 and ADW 4.2 workstation.Results:MSCTA could clearly display spacious anatomic details of cerebral aneurysm,including its origin,size,neck width,and trend etc.MSCTA results of 19 cases were consistent with those of operations.The diameter of the smallest cerebral aneurysm shown in our research was about 3 mm.As a non-invasive examination,MSCTA could also be applied in post-operational evaluation of cerebral aneurysm by observing the location of silver clip and the distant vessels.Besides,MSCTA could be used to diagnose arteriovenous malformation and moyamoya disease.Of all the three-dimentional imaging methods,volume rendering (VR)is the best means to display the cerebral vascular diseases.Conclusion: As a non-invasive examination,MSCTA plays an important role in detection,pre-operational and post-operational evaluation of cerebral vascular diseases.

  8. Virtual colonoscopy by multi-slice CT

    Objective: To evaluate the usefulness of VC with MSCT and to determine the sensitivity (Se) and specificity (Sp) of this method in comparison with conventional colonoscopy (CC). Method and Materials: Thirty patients were studied with MSCT and CC. CTs were performed with a multislice CT scanner, with slices of 2,5 mm thickness, 1,3 mm reconstruction interval, 50 mAs, 120 Kv. The mean acquisition time was 25 seconds. Findings were divided in normal and pathologic. The latter was subdivided according to the diameter of the lesions: 2a) 9 mm. Results: The Se and Sp was in 2a) 82% and 78%; in 2b) 100% and 93%; and in 2c) 100% and 100% respectively. Conclusion: VC with MSCT showed high Se and Sp for the detection of elevated lesions. Its fast way of acquisition allows better patient tolerance and better resolution without respiratory artifacts. (author)

  9. 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

    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.

  10. Magnetic resonance imaging in neurologic diseases--comparison with computed tomography.

    Chang, K. H.; Han, M. C.; Kim, C. W.

    1987-01-01

    Magnetic resonance (MR) and computed tomography (CT) imagings were compared in 121 patients with various neurologic diseases. MR was performed with either 0.15 Tesla resistive or 2.0 Tesla superconducting systems developed by Korea Advanced Institute of Science and Technology (KAIST), using multi-slice spin echo technique with a variety of pulse sequences reflecting proton density, T1 and T2 relaxation times. MR was more advantageous in the detection of the lesions, accurate depiction of the ...

  11. 多层螺旋CT在胃肠间质瘤定位和定性诊断中的价值%Values of multi-slice CT in differential diagnosis of gastrointestinal stromal tumors

    卢文彬

    2014-01-01

    目的:探讨多层螺旋CT在胃肠道间质瘤( GIST)定位和定性中的诊断价值。方法:对本院30例手术病理证实为胃肠间质瘤的患者的CT影像特点进行回顾性分析。均行16层螺旋CT平扫和增强扫描,探讨病灶位置、大小及有无坏死等情况。结果:胃肠道间质瘤单发患者21例、多发9例;其中17例肿瘤部位在胃部、8例位于小肠、5例位于直肠。19例向腔内外同时生长、8例向腔外生长、3例向腔内生长。恶性GIST 强化不均匀,可有邻近脏器侵犯。16层螺旋CT定性准确率为83.3%(25/30)、定位准确率90.0%(27/30)。结论:CT 增强扫描有利于GIST的定位诊断及对肿瘤良恶性质的判断,能准确显示肿瘤的部位、形态、大小,是目前检查GIST的重要方法之一。%Objective:To investigate the diagnosis values of multi-slice CT ( MSCT ) on diagnosis of gastrointestinal stromal tumors ( GIST) . Methods:The CT characteristics of 30 tumors of pathological confirmed GIST in our hospital were retrospectively analyzed. All patients were scanned with unenhanced and enhanced 16-slice CT, and then the location, size and necrosis of lesions were analyzed. Results:Among all 30 cases, single lesions of GIST were 21 cases, and motile lesions of GIST were 9 cases. And 17 cases located at stomach, 8 cases at small intestine, and 5 cases at rectum. There were 19 cases simultaneously inside and outside the chamber, 8 cases of external cavity growth, and 3 cases of intracavity growth. The malignant GIST exhibited inhomogeneous enhancement and invasion to adjacent organs. Accuracy of 16-slice CT diagnosis for qualitative analysis was 83. 3% ( 25/30 ) and for location was 90. 0% ( 27/30 ) of GISTs. Conclusion: CT enhanced scan benefits the localization diagnosis of GIST and the determination of benign or malignant tumors. It could accurately show the location, form and size of tumors, which is one of the significant methods to examine

  12. 多层螺旋CT对健康成人肾周间隙及肾筋膜的测量%Anatomy of the perirenal space and renal fascia:a multi-slice spiral CT observation

    王娜; 刘荣波; 孔维芳

    2011-01-01

    Objective: To measure the renal fascia and evaluate the anatomy of perirenal space and its communications sand boundarics with multi-slice spiral CT (MSCT). Methods : MSCT scanning was performed in 97 normal subjects , and the multiplanar reconstruction (MPR) images of perirenal space and its anatomical communications were obtained on a postprocessing workstation. The shapc, size and anatomical communications of the perirenal space were observed and measured.Results : Between the upper and lower pole of kidney,the detection rate of renal fascia was 100%. It was easier to visualize the renal fascia on MPR images than those on transverse CT images. The thickness of the left and right renal fascia was (0.13+0. 02)cm and (0. 12+0. 02)cm, respectively. No significant difference in renal fascia thickness was found between different gender and age groups (all P>0.05). Different types of adhesion and anatomical communication of renal fascia were distinctly visualized on MSCT images. Conclusions : MSCT and MPR images could clearly visualize the morphologic features and anatomical communication of the perirenal space, which may be helpful in making diagnostic decisions.%目的:通过多层螺旋CT对正常成人肾筋膜和肾周闯隙的观察和测量.探讨多层螺旋CT显示肾筋膜的附着及通连情况.方法:搜集在我院接受腹部CT增强扫描检查的健康成人资料97例,采用多层螺旋CT扫描对肾周间隙行多平面三维重组,测定肾筋膜的厚度,并观察肾筋膜的显示率以及肾筋膜向上和向下的通连情况.结果:肾筋膜在肾脏上、下极之间的显示率为100%,且双侧肾筋膜在MPR图像上的显示率大于轴面图像.左、右侧肾筋膜厚度分别为(0.13±0.02)cm和(0.12±0.02)cm,不同性别及年龄组别间筋膜厚度差异无统计学意义(P>0.05).多层螺旋CT发现肾筋膜的附着及肾周间隙的通连情况具有不同类型:①双侧肾前、后筋膜向下融合,融

  13. MSCT尿路成像技术在泌尿系统疾病诊断中的价值%The value of multi-slice CT urography in diagnosis of urinary tract diseases

    沈纪芳; 朱玉春; 王建良

    2012-01-01

    目的 探讨多层螺旋CT(MSCT)尿路成像技术在泌尿系统疾病诊断中的价值.方法 对80例泌尿系统疾病患者行CT尿路成像检查,通过常规平扫、动脉期、静脉期、延迟期图像数据进行多平面重组法(MPR)、曲面重组法(CPR)、最大密度投影法(MIP)和容积成像法(VR)进行三维重组,对影像图像进行分析.结果 CT尿路成像技术能够清晰显示泌尿系统的整体结构和输尿管走行和周围组织的关系.80例中,泌尿系统结石46例,输尿管癌4例,肾盂癌1例,先天性发育畸形5例,输尿管炎性狭窄9例,输尿管瘘1例,输尿管息肉1例,盆腔内恶性肿瘤累及或术后侵犯7例,正常6例.MSCT尿路成像诊断特异性为i00%(80/80),诊断准确率为95%(76/80);1例输尿管息肉和3例炎性狭窄误诊为输尿管癌,误诊率为5%(4/80).结论 MSCT尿路成像图像清晰直观,可以作为早期确诊泌尿系统疾病的有效影像检查方法.%Objective To investigate the diagnostic value of multi-slice CT(MSCT) urography in urinary tract diseases. Methods CT urography was performed in 80 cases with urinary tract diseases. The multiplanar reconstruction (MPR), maximum intensity recontruction (MIP), cured planar reformation(CPR) and volume rendering(VR) were reconstructed based on the data extracted by conventional plain scan,arteral phase, venous phase and lag period scaa Results MSCT urography provided clear three dimensional images of the whole kidney, ureter and urinary bladder, the entire and partial structure,shape and relation with the tissues surrounding them. Of 80 cases, the diagnosis of urinary calculus was confermed in 46 cases, ureteral carcinoma in 4 cases, renal pelvic carcinoma in 1 case,urinary congenital malformation in 5 cases, urinary inflammation in 9 cases, ureteral fistula in 1 case,ureteral polyp in 1 case, ureter invaded by palvic magligant mass in 7 cases, and normal in 6 cases. In the diagnosis of urinary tract diseases, the

  14. ROC分析在多层螺旋CT综合性诊断孤立性肺结节良恶性中的应用%Role of ROC analysis in comprehensive diagnosis to differentiate malignant from benign solitary pulmonary nodules with multi-slice spiral CT

    杨玉海; 邵广瑞; 宋磊; 张伟

    2011-01-01

    Objective To study the role of receiver operating characteristic (ROC) analysis in comprehensive diagnosis to differentiate malignant from benign solitary pulmonary nodules (SPNs) with multi-slice spiral computed tomography (MSCT).Methods 177 SPNs were examined with MSCT and pathologically confirmed by surgery and/or needle biopsy.All MSCT images were assessed and graded by three senior radiologists on the basis of malignant likelihood of morphological and density characteristics.According to the maximum diameter (D), ROC curves were constructed and optimal thresholds were determined for diagnosis of malignancy in SPNS of D≤3.0 cm, 2.0 cm < D≤3.0 cm and D≤2.0 cm.ROC analysis was used to evaluate the efficiency of MSCT in differentiating malignant from benign SPNs.The area under the ROC curve ( Az ) was used as an index for diagnostic efficiency with MSCT.Az values were statistically analyzed by Z-test.Results A, values of ROC curves were 0.879 ± 0.030 in SPNs of D ≤3.0 cm, 0.899 ± 0.039 in SPNs of 2.0 cm < D≤3.0 cm and 0.867 ± 0.044 in SPNs of D≤2.0 cm.The differences were statistically significant according to the Z-test ( P < 0.05).The three optimal thresholds for diagnosis of malignancy were 3.0, 3.5 and 2.5.Conclusion Application of ROC analysis is of obvious value in the differential diagnosis of SPNs with comprehensive imaging characteristics obtained by MSCT.It is favorable to combine the diagnosis of SPNs by MSCT with the malignant probability and to improve the treatment of SPNs in clinical practice.%目的 探讨在孤立性肺结节(SPN)良恶性的多层螺旋CT(MSCT)综合性诊断中ROC分析的应用价值.方法 经手术和/或穿刺活检组织病理结果 证实的SPN 177个,由3位资深的CT诊断医师分别对每个SPN的MSCT图像进行全面分析,依其影像特征进行综合评分,根据SPN的最大径(D),以MSCT评分为分类值,分别绘制D≤3.0 cm、2.0 cm<D≤3.0 cm和D≤2.0 cm SPN良恶性诊断的ROC曲

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

    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...

  16. Congenital anomalies of coronary arteries: Diagnosis with 64 slice multidetector CT

    Objective: Congenital coronary artery anomalies are generally incidental, uncommon and asymptomatic. Some can cause severe potentially life threatening symptoms. The common mode of studying the coronary arteries is Conventional Coronary Angiogram. ECG-gated-multidetector CT is a non invasive modality. The objective of our study was to identify rare congenital coronary artery anomalies and discuss their clinical significance. Material and methods: A total number of 900 MDCT coronary angiograms were carried out at our institution between the period of April 2006 and October 2010. Patients with coronary artery anomaly constituted the subject of study. Results: The incidence of anomalous anatomical origin and course of the coronary arteries in our study was 1.55%. Hemodynamical significance was seen in five patients. 3 cases of single coronary artery originating from right coronary sinus were seen. 1 case of anomalous left coronary artery arising from main pulmonary artery was seen. 4 cases of anomalous RCA arising from left aortic cusp, 6 cases of absent LMCA with separate origin of LAD and LCX were seen. Conclusion: Multidetector row CT is a noninvasive modality in cardiac imaging. It provides superior resolution of coronary tree and its variant. No projectional vascular overlap is seen. Various postprocessing techniques outclass catheter angiography imaging. Definition of ostia and proximal course of the coronary arteries by Multidetector CT is better than catheter angiography.

  17. Clinical application of 64-slice spiral CT for apical hypertrophic cardiomyopathy

    Objective: To evaluate the clinical application values of 64-row MSCT for apical hypertrophic cardiomyopathy (AHCM). Methods: Twenty-one patients with AHCM were included in this study, 14 patients were diagnosed by echocardiography (UCG), and 7 patients were diagnosed by MRI. All patients underwent MSCT exam, and 5 patients also had ventriculography and coronary angiography. The left ventricular wall thickness in end-systole and end-diastole phases were measured at MSCT workstation, the left ventricular apex thickening rate (LVAT) and the ratio of maximum wall thickness of the left ventricular apex (LVA) to the left ventrieular posterior wall thickness (LVA/LVPW) in end-diastole phase were calculated. The left ventricular end-diastolic volume (LVEDV) and left ventricular ejection fraction (LVEF) were quantitatively evaluated with cardiac functional analysis software. The results were compared with the measurement results from the normal control group (30 volunteers). The independent-samples t test was used for the statistics. At the same time, the coronary stenosis was measured. Results: Diffuse or partial thickening of the LV apical myocardium were found in the four-chamber view and two-chamber view of MSCT images, which leaded to the deformation of the left ventricle chamber. The LVEDV were (82.6± 11.4) and (108.5±10.6) ml in the AHCM group and the control group, respectively; the LVA were (20.6±3.4) and (9.9±1.5) mm; LVA/LVPW were 2.1±0.5 and 1.1±0.2; the LVAT were (25.6± 4.7)% and (81.5±8.5)%. There were significant differences in LYEDV, LVA, LVA/LVPW and LVAT between the two groups (t=8.32 and 15.29, P 0.05). Five patients had myocardium bridging and 4 patients had coronary stenosis. Conclusion: AHCM can be diagnosed accurately with MSCT, and the cardiac anatomy, function and coronary artery are also assessed simultaneously. (authors)

  18. Selection and application of multi-slice CT 3D reconstruction techniques in assisting mini-implant ahchorage implant surgery%多层螺旋CT三维重建技术在辅助微螺钉种植支抗植入中的选择应用

    陈京奕; 吴晓伟; 张洪刚; 焦建军; 张学强; 姚传臣

    2011-01-01

    背景:提高正畸支抗系统微螺钉种植体稳定性的关键在于种植前对局部骨质、骨量进行精确评估,但常规二维影像学检查,如根尖片、曲面断层摄影片、侧位头影测量片等均存在不同程度的局限性.目的:分析总结多层螺旋CT多种图像重建技术在辅助微螺钉种植支抗植入中的不同特点及优势,以便精确指导微螺钉的种植,提高其稳定性.方法:种植前以多层螺旋CT对猪颅骨进行定位扫描及多种图像重建,通过多种图像联合应用初步观测种植区骨质骨量及解剖情况,然后利用计算机在影像上精确设计三维种植角度,根据影像信息制作隧道式手术模板指导种植32枚微螺钉支抗,种植后多层螺旋CT再次扫描重建,将种植前后多层螺旋CT设计及测量角度与术后解剖组织块实物测量角度作对比分析.结果与结论:32枚微螺钉种植情况满意,无伤及邻近牙根及周围重要组织结构的情况.种植前设计与种植后多层螺旋CT测量角度比较,以及种植后多层螺旋CT测量与实物测量角度比较,在轴位面及侧断面上其差异均无显著性意义(P > 0.05),且一致性极好.说明多层螺旋CT能够提供精确而丰富的影像信息,恰当选择合理应用能充分实现微螺钉种植影像学检查目的,从而为提高种植的成功率提供可靠保障.%BACKGROUND: The key method to improve the stability of miniscrew orthodontic anchorage system is accurate preoperative bone mass evaluation in the implant region. Routine 2D image examinations such as periapical radiography and panoramic tomography and lateral cephalometric radiography have limitations.OBJECTIVE: To analyze the traits and advantages of various multi-slice CT (MSCT) reconstruction images in assisting miniscrew anchorage surgery to improve the stability of miniscrew.METHODS: Preplant MSCT scanning and various images reconstruction were made and helped to exam the peri-implant bone

  19. CT Detection Systems

    Full Text:Godfrey N. Housnfield received the Nobel Prize in 1979 for inventing Computed Tomography in 1967. Since then the invention has evolved and is part of everyday diagnostics in every hospital. The first clinical Computed Tomography was installed in 1971. Since middle seventies a group of Physicists and Engineers have been development Computed Tomography in Haifa, under the name of different companies. The group started as Elscint, was bought by Picker in 1999, then modified the name to Marconi and was bought by Philips in 2002. Several of the first developments of Computed Tomography systems were done in Haifa, in particular in the detectors. Among several firsts, he first Solid State Computed Tomography detector and first multi-slice Computed Tomography should be mentioned. The evolution of Computed Tomography detection systems will be described. Nowadays Multi Slice Computed Tomography Detectors enable new applications like Computed Tomography Angiography and virtual Colonoscopy. The evolution of Computed Tomography detection systems will be described, from single slice to today 64 slice arrays and beyond

  20. 多层螺旋CT平扫联合尿路重建在急性肾绞痛诊断中的临床应用%Clinical application of multi-slice helical CT plain scan combined with urinary reconstruction in diagnosis of acute renal colic

    陈刚; 吴小候; 尹志康; 何云锋

    2011-01-01

    目的 探讨多层螺旋CT平扫联合尿路重建在急性肾绞痛诊断中的的临床应用价值.方法 将126例急诊肾绞痛患者随机分两组:CT组(67例)和静脉尿路造影(IVU)组(59例),CT组行多层(16层或64层)螺旋CT平扫联合尿路重建,IVU组行相关准备后行腹部X线平片(KUB)联合IVU检查.在明确诊断为输尿管梗阻或输尿管结石后,急诊行输尿管镜碎石术或置管治疗,比较两组患者的术前结石确诊率、肾绞痛缓解时间、住院时间及住院总费用等.结果 所有患者术后肾绞痛均缓解,CT组术前结石确诊率明显高于IVU组(P<0.05),CT组肾绞痛缓解时间和住院时间短于IVU组(P<0.05),CT组住院总费与IVU组比较差异无统计学意义(P>0.05).结论 多层螺旋CT平扫联合尿路重建对于急诊肾绞痛患者的诊治是高效和相对经济的.%Objective To investigate clinical application of multi-slice helical CT plain scan combined with urinary reconstruction in diagnosis of acute renal colic. Methods 126 patients with acute renal colic were randomized divided into two groups. 67 cases were diagnosed by multi-slice helical CT combined with urinary reconstruction and 59 cases were diagnosed by abdominal plain film radiography combined with IVU. All patients were treated by ureteroscope lithotripsy. The stone diagnosis rate was compared as well as the renal colic time , the hospitalization time and the hospitalization cost. Results The stone diagnosis rate in CT group was more than that in IVU group(P<0. 05). However,the renal colic time hospitalization time in CT group was less than that in IVU group as well as hospitalization time(P<0. 05). There was no significantly difference on the hospitalization cost between two groups(P>0. 05). Conclusion Multi-slice helical CT plain scan combined with urinary reconstruction is efficient and economic in diagnosis of acute renal colic.

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

    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

  2. Primary graft dysfunction; possible evaluation by high resolution computed tomography, and suggestions for a scoring system

    Belmaati, Esther; Jensen, Claus; Kofoed, Klaus F; Iversen, Martin; Steffensen, Ida; Nielsen, Michael B

    2009-01-01

    reproducibility of these systems were discussed. Lastly, the future perspectives for 64-multi-slice computed tomography (MSCT) in relation to PGD were discussed. Few studies on scoring systems of lung tissue by HRCT in ARDS patients and idiopathic pulmonary fibrosis (IPF) patients were found. Most studies were...... performed on patients with cystic fibrosis (CF). Sensitivity of HRCT for the detection of parenchymal changes is superior to other imaging methods. High levels of reproducibility are achievable amongst observers who score HRCT lung images. Development of standardized criteria that specify the inclusion...

  3. Quality assessment of clinical computed tomography

    Berndt, Dorothea; Luckow, Marlen; Lambrecht, J. Thomas; Beckmann, Felix; Müller, Bert

    2008-08-01

    Three-dimensional images are vital for the diagnosis in dentistry and cranio-maxillofacial surgery. Artifacts caused by highly absorbing components such as metallic implants, however, limit the value of the tomograms. The dominant artifacts observed are blowout and streaks. Investigating the artifacts generated by metallic implants in a pig jaw, the data acquisition for the patients in dentistry should be optimized in a quantitative manner. A freshly explanted pig jaw including related soft-tissues served as a model system. Images were recorded varying the accelerating voltage and the beam current. The comparison with multi-slice and micro computed tomography (CT) helps to validate the approach with the dental CT system (3D-Accuitomo, Morita, Japan). The data are rigidly registered to comparatively quantify their quality. The micro CT data provide a reasonable standard for quantitative data assessment of clinical CT.

  4. Application value of multi-slice spiral CT image post-processing technique in the diagnosis of tracheal and bronchus foreign body in children%多层螺旋CT后处理技术对小儿气管、支气管异物的诊断价值

    巫恒平; 仲建全; 郭欢

    2015-01-01

    目的:探讨多层螺旋CT图像后处理技术在小儿气管、支气管异物诊断中的应用价值。方法通过对我院25例疑似支气管异物的患儿行多层螺旋CT扫描,采用MPR、Min IP、VR及VE等后处理技术,分析并比较其在气管、支气管异物中的诊断价值。结果经临床纤维支气管镜证实为气管、支气管异物的25例患儿均获得清晰的CT图像及后处理图像,多平面重建(MPR)对异物显示较佳,显示率为100%(25/25),容积再现(VR)能明确异物的位置及与气管的关系,显示率为97%(24/25),最小密度投影(Min IP)对异物的测量较精确,显示率为97%(24/25),及仿真内窥镜(VE)能准确显示异物在气管内的位置及对气管的堵塞情况。结论 MSCT后处理技术在小儿气管、支气管异物诊断中准确率较高,可成为首选的影像学检查方法。%Objective To explore the application value of multi-slice spiral CT (MSCT) image post-process-ing technique in the diagnosis of tracheal and bronchus foreign body in children. Methods Twenty-five children sus-pected with bronchial foreign bodies in our hospital were scanned by multi-slice spiral CT. Then the imaging data were processed by techniques of multi planar reconstruction (MPR), minimum intensity projection (Min IP), volume rendering (VR) and virtual endoscopy (VE). The diagnosis value of the techniques for trachea, bronchial foreign body was analyzed and compared. Results The 25 cases all obtained clear CT images and post-processed images. MPR displayed the foreign body best, with the display rate of 100%(25/25). VR could clear display foreign body and its re-lationship with the trachea, with the display rate of 97%(24/25). Min IP was good at distinguish the accurate measure-ment of the foreign body, and the display rate was 97%(24/25). VE could show the foreign bodies in the trachea of the position and the blockage of the trachea accurately. Conclusion The MSCT image post

  5. The influence of gallbladder fossa fluid accumulation on gallbladder wall thickness in liver cirrhosis on sonographic imaging correlation with multi-slice CT scanning%利用CT三维重建分析肝硬化伴胆囊窝积液对胆囊壁超声成像的影响

    谭洁莹; 韦程纲; 谢琦

    2012-01-01

    目的:探讨肝硬化伴胆囊窝积液病者胆囊壁超声与CT三维重建在影像成像以及胆囊壁厚度测量的方面上对比差异.方法:对比39例患者于空腹状态同时行超声以及多层螺旋CT检查的影像图像,B超和CT测量胆囊厚度情况,绘制散点图,并进行Pearson相关性分析,应用配对样本t检验比较胆囊壁厚度情况.结果:①与CT三维重建图像对比,发现其中31例出现胆囊窝积液超声漏诊情况,并且发现胆囊壁厚度的超声测量值,存在高估情况的16例,低估情况2例.②B超与CT胆囊壁厚度的测量值相关系数为0.648 (P<0.000).③B超测量胆囊壁厚度((6.2±2.6)mm)较CT测量胆囊壁厚度((4.5±2.0)mm)平均值更大,测量差异具有统计学意义(t=4.465,P<0.000),变异系数分别为0.42、0.44.结论:局限性胆囊窝积液在CT检查中检出率较超声高,对肝硬化患者胆囊壁增厚与局限性胆囊窝积液能够更准确地进行鉴别诊断.%Objective: To discuss the difference of gallbladder wall thickness in liver cirrhosis with gallbladder fossa fluid accumulation on ultrasound scanning and CT multi-plane reconstruction images. Materials and Methods: Ultrasound scanning and multi-slice CT were performed in 39 patients who had gallbladder fossa fluid accumulation with liver cirrhosis, all cases were under fasting condition. Gallbladder wall thickness was measured both on ultrasonographic and multi —slice CT 3D reconstruction images. The scatter diagram was drawn and Pearson correlation analysis and paired sample t test comparison of gallbladder wall thickness were also carried out. Result: Compared with multi-plane CT reconstruction, (1) Ultrasound missed the diagnosis of gallbladder fossa fluid accumulation in 31 cases, over estimation of gallbladder wall thickness in 16 cases, and under estimation of the thickness in 2 cases. (2)The correlation coefficient of ultrasound detection of gallbladder wall thickness with CT detection was

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

    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.)

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

    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.)

  8. 多层螺旋CT泌尿系造影诊断上尿路梗阻性疾病20例分析%Application of multi-slice spiral CT urography for diagnosis of upper urinary tract obstructive disorder in 20 cases

    管军; 金洁; 朱文海; 陆进; 诸伟; 吴少峰

    2013-01-01

    Objective To investigate the application value of multi-slice spiral CT urography(MSCTU) in the diagnosis of upper urinary tract obstructive disorder. Methods 20 patients with upper urinary tract obstructive disorder treated from July 2008 to June 2012 were performed MSCTU scan. The primary data were performed the three dimensional reconstructions for the comparison with the results of X-ray,B-type ultrasound and IVU. Results 5 cases were developed at 1 h,1 case was postponed to develop at 2 h,3 cases had undeveloped one side and other 11 cases were normally developed. Conclusion MSCTU has the high sensitivity and high specificity,and can clearly display the upper urinary tract lesions,congenital variations and deformities.%目的 探讨多层螺旋CT泌尿系造影(MSCTU)在上尿路梗阻性疾病诊断中的应用价值.方法 选择2008年7月至2012年6月该院收治的上尿路梗阻性疾病20例,行多层螺旋CT扫描,将原始数据三维重建后进行尿路成像,并与X线平片、B超、静脉尿路造影检查结果进行对比分析.结果 5例于1 h显影,1例延迟至2 h显影,3例1侧未显影,其他11例均正常显影.结论 MSCTU是一种无创伤且安全有效的非侵袭性影像检查方法,对上尿路梗阻性疾病的诊断有重要的临床应用价值.

  9. 良、恶性梗阻性黄疸应用多层螺旋CT(MSCT)的临床诊断价值研究%Clinical diagnostic and value study of multi slice spiral CT (MSCT) application for benign and malignant obstructive jaundice

    孙赞江

    2015-01-01

    目的:探讨多层螺旋 CT(MSCT)对于良、恶性梗阻性黄疸的临床诊断价值。方法回顾分析72例梗阻性黄疸患者的临床资料与影像学资料,分析 MSCT 对于梗阻性黄疸的良恶性诊断价值。结果 MSCT 对于梗阻性黄疸的定位诊断准确率为100%,对恶性梗阻性黄疸的诊断准确率为96.43%,对良性梗阻性黄疸的诊断准确率为95.45%。结论MSCT 对于梗阻性黄疸的定位及定性诊断具有较高的准确性,值得在临床中推广应用。%Objective investigate clinical diagnostic value of multi-slice spiral CT (MSCT) for diagnosis of benign and malignant obstructive jaundice. Method analyze and review clinical and imaging data of 72 patients with obstructive jaundice, and analyze diagnostic value of MSCT for benign and malignant obstructive jaundice. Result diagnostic accuracy of MSCT for obstructive jaundice diagnosis is 100%, and for malignant obstructive jaundice is 96.43%, for benign obstructive jaundice is 95.45%. Conclusion MSCT has high accuracy for localization and qualitative diagnosis on obstructive jaundice, which is worthy of being spreaded and applied clinically.

  10. 多层螺旋CT后处理技术在膝关节交叉韧带MR扫描方式中的应用%Application of multi-slice spiral CT images post-processing in MR scanning mode for the cruciate ligament of knee joint

    严由伦; 李荣; 董燕; 余建国

    2013-01-01

    目的 通过多层螺旋CT多平面重建后处理方式指导膝关节交叉韧带MR成像的最佳方位,提高交叉韧带MR图像的显示程度.方法 应用多层螺旋CT对50例正常成人膝关节进行扫描获得容积数据,利用多平面重建后处理技术重建膝关节标准矢状面、标准冠状面图像,再根据膝关节交叉韧带解剖走行重建斜矢状面图像(通过横断面和冠状面确定定位线:横断面,定位线与股骨外侧髁内侧面基本平行或与标准矢状面呈向内倾斜10°角;冠状面,定位线与髁间隆起至股骨髁间窝的连线平行或向外倾斜与下肢长轴约呈15°角)和斜冠状面图像(通过横断面和矢状面确定定位线:横断面,定位线平行股骨内、外侧髁后缘连线;矢状面,定位线平行于前交叉韧带走行方向或与标准冠状面呈35°~40°角).对所得膝关节交叉韧带图像显示效果进行评价.并将斜矢状面、斜冠状面定位方案应用到磁共振扫描方式中.结果 多层螺旋CT和MR膝关节交叉韧带图像显示程度一致,两者无显著性差异.前交叉韧带在斜冠状面显示率100%,在斜矢状面MR图像显示率达到98%,后交叉韧带在标准矢状面显示率100%.结论 将多层螺旋CT多平面后处理技术对膝关节交叉韧带成像的最佳方位,应用于MR膝关节交叉韧带扫描方式中具有操作简单,结论准确和明确的指导意义.%Objective To study the most optimal orientation of magnetic resonance imaging the cruciate ligament of knee joint assisted by multi-planar reconstruction(MPR) of mlti-slicc spiral CT ,in order to advance the clarity of representation. Methods Bilateral knee joints of fifty healthy adults were scanned by multi-slice spiral CT, and volume data was obtained. The knee joint images on sagittal plane and coronc plane were reconstructed by MPR. Then, the oblique sagittal planc( using transverse and coronal plane as a locating line. On the transverse plane, the

  11. Multi-slice CT pulmonary function evaluation in emphysema

    Objective: To explore the feasibility of evaluating the lung function by MSCT in emphysema. Methods: The MSCT scan and pulmonary function tests (PFT) were respectively performed in 147 receptors within one week. They were randomly divided into 2 groups: group A (120 receptors), including normal, mild, moderate and severe abnormal pulmonary function based on the PFT, for comparing the correlation between pulmonary quantitative indexes of MSCT pulmonary function and PFT and settingup the primary, grade criteria of abnormal pulmonary, function in emphysema, group B (27 receptors) for evaluating the diagnostic accuracy in group A. The total lung was respectively scanned at the full inspiration and full expiration with MSCT. The pulmonary quantitative indexes of MSCT were measured with Siemens Pulmo pulmonary quantitative software. Results: There was correlation between pulmonary quantitative indexes of MSCT and PFT. The Piex/in-910 showed best correlation with FEV1% (r= -0. 905, P-910 (χ20.267, P=0.966, accuracy 81.5%), and the primary criteria for abnormal pulmonary, function of emphysema was normal (0-9.9), mild (10.0-34.9), moderate (35.0-74.9) and severe (≥75.0). Conclusion: It is feasible to evaluate the abnormal lung function of emphysema with pulmonary quantitative indexes of CT. The Piex/in910 was the most effective one in various indexes. (authors)

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

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

    2016-01-01

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

  13. Development of computer aided diagnosis for lung cancer CT screening

    The introduction of low dose lung cancer helical CT screening to the clinical site has been the fundamental basis of research on Computer Aided Diagnosis (CAD) using thoracic CT images. Our purpose is the early detection of lung cancer leading to its early treatment, in order to reduce the mortality of lung cancer. From multi-slice CT, lung cancer screening has been activated more. Since CT screening contains a lot of images compared with the conventional X-ray, research and development on the utilization of computer and network using the new diagnosis support technology is required. Due to the demand from actual clinical site, the research group from The University of Tokushima has started the research and development of CAD using lung cancer CT images. We report the result and the future works. (author)

  14. 多层螺旋CT核磁共振成像诊断腕关节损伤的临床应用研究%Clinical Analysis of Multi Slice Spiral CT Magnetic Resonance Imaging in Diagnosis of Wrist Joint Injury

    全宏卫

    2015-01-01

    目的:探讨多层螺旋CT(MSCT)与核磁共振成像(MRI)诊断腕关节损伤的价值。方法收集腕关节损伤患者112例,分别应用MSCT、MRI和联合诊断,比较三种诊断方法的诊断效能。结果骨折组中MRI对软骨损伤、骨挫伤和隐匿性骨折的检出率显著高于MSCT,而移位碎骨折片、关节脱位以及关节骨折的检出率显著低于MSCT(P<0.05);无骨折组中MRI检出隐匿性骨折、软骨损伤以及骨挫伤均显著高于MSCT,而关节脱位检出率显著低于MSCT(P<0.05)。结论 MSCT联合MRI诊断腕关节损伤具有较高的检出率以及诊断效能,值得推广应用。%Objective To evaluate multi-slice spiral CT (MSCT) and magnetic resonance imaging (MRI) of wrist injury diagnosis. Methods 112 cases of wrist injury, respectively by MSCT, MRI and combined diagnosis, diagnostic ef iciency comparison of three diagnostic methods. Results In the group of MRI fracture detection rate of cartilage, bone contusions and occult fractures were significantly higher than that of MSCT, and shift broken fracture and joint dislocation and the fracture of the joint detection rate was significantly lower than that of MSCT ( <0.05);without fracture in the group of MRI detected occult fracture, cartilage damage and bone contusion were significantly higher than MSCT, while the dislocation rate was significantly lower than that of MSCT ( <0.05). Conclusion MSCT combined with MRI in diagnosis of wrist joint injury detection rate and diagnosis ef iciency is high, it is worthy of popularization and application.

  15. COMPUTING

    M. Kasemann

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

  16. COMPUTING

    P. McBride

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

  17. COMPUTING

    I. Fisk

    2011-01-01

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

  18. COMPUTING

    M. Kasemann

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

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

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

    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.

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

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

  2. The analysis of gastric function using computational techniques

    Young, P

    2002-01-01

    The work presented in this thesis was carried out at the Magnetic Resonance Centre, Department of Physics and Astronomy, University of Nottingham, between October 1996 and June 2000. This thesis describes the application of computerised techniques to the analysis of gastric function, in relation to Magnetic Resonance Imaging data. The implementation of a computer program enabling the measurement of motility in the lower stomach is described in Chapter 6. This method allowed the dimensional reduction of multi-slice image data sets into a 'Motility Plot', from which the motility parameters - the frequency, velocity and depth of contractions - could be measured. The technique was found to be simple, accurate and involved substantial time savings, when compared to manual analysis. The program was subsequently used in the measurement of motility in three separate studies, described in Chapter 7. In Study 1, four different meal types of varying viscosity and nutrient value were consumed by 12 volunteers. The aim of...

  3. COMPUTING

    I. Fisk

    2013-01-01

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

  4. Computer

    Atkinson, Paul

    2011-01-01

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

  5. COMPUTING

    I. Fisk

    2010-01-01

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

  6. COMPUTING

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

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

  7. 多层螺旋 CT 灌注成像在脑胶质瘤分级中的价值与微血管密度的相关性研究%Application value of multi-slice spiral CT perfusion imaging in brain gliomas and its relation with microvessel density

    洪建斌; 许乃滔; 侯志雄

    2014-01-01

    Objective To study the value of multi-slice spiral CT (MSCT ) perfusion imaging in grading of brain glioma(BG) and its correlation with microvessel density (MVD) .Methods A total of 89 BG patients ,treated in this hospital from March 2010 to March 2013 ,were enrolled and divided into high grade group and low grade group , according to the grading levels .MSCT parameters and MVD ,vascular endothelial growth factor(VEGF) levels were compared ,and the correlation between relative cerebral blood flow (rCBV) and MVD ,VEGF were analyzed .Results Levels of cerebral blood flow (CBF) ,rCBF ,cerebral blood volume(CBV) ,relative CBV(rCBV) of high grade group were significantly higher than low grade group (P< 0 .05) .The positive rate of VEGF in high grade group was 89 .13% (41/46) ,higher than the 55 .81% (24/43) of low grade group(P<0 .05) .Level of MVD in high grade group was 70 .76 ± 8 .85 ,significantly higher than the 37 .75 ± 5 .65 of low grade group(P<0 .05) .rCBV level was positive-ly correlated with MVD and VEGF expression level (r= 0 .610 and r= 0 .631 ,P< 0 .05) .Conclusion rCBV level could be positively correlated with MVD and VEGF expression level in patients wit BG .MSCT could provide fine im-aging evidence for the grading of BG .%目的:研究多层螺旋CT(MSCT)灌注成像在脑胶质瘤(BG)分级中的价值与微血管密度(MVD)的相关性。方法选择该院2010年3月至2013年3月诊治的89例BG患者作为观察对象,根据BG分级标准分成高级别组以及低级别组。对比两组MSCT参数以及MVD、血管内皮生长因子(VEGF);分析相对脑血容量(rCBV)和MVD、VEGF的相关性。结果高级别组的脑血流量(CBF)、相对脑血流量(rCBF)、脑血容量(CBV)、rCBV均明显高于低级别组;高级别组VEGF阳性率为89.13%(41/46),明显高于低级别组的55.81%(24/43);高级别组MVD为70.76±8.85,明显高于低级别组的37.75±5.65,差

  8. 多层螺旋CT及多维重建技术对隐匿性肋骨骨折的诊断价值探讨%Study of the multi-slice CT and for multi-dimensional reconstruction techniques the diagnosis of occult rib fracture

    蔡洪涛

    2014-01-01

    目的:考察多层螺旋CT(MSCT)联合多维重建技术对隐匿性肋骨骨折的临床诊断价值,为该类疾病临床诊断提供参考。方法:以我院2012年7月至2014年2月间收治的73例隐匿性肋骨骨折患者为研究对象,使用MSCT联合VR、SSD、CRP等多种重建技术对患者进行检查,统计并分析影像学检查结果。结果:73例患者经MSCT检查确诊隐匿性肋骨骨折107处,骨折多发于肋骨角(59.81%)且以非完全线性骨折为主(91.59%)。所用多维重建技术的诊断精度依次为:CRP(100.0%)>MPR(97.19%)>SSD(85.89%)>VR(78.50%)>MIP(27.88%)。结论:MSCT联合多维重建技术对隐匿性肋骨骨折具有较为明确的诊断价值,MSCT与CRP/MPR及VR等联用可获得较为理想的诊断率。%Objective:To investigate the clinical value of the multi-slice CT and for multi-dimensional reconstruction techniques the diagnosis of occult rib fracture, to provide a reference for the diagnosis of occult rib fracture.Methods:73 cases patients with occult rib fracture which received treatment during 2012.07 to 2014. 02, were the objects for this study, used MSCT joint VR, SSD, CRP and other reconstruction techniques to detected the occult rib fracture of all the patients, and then the imaging results of the patients were analyzed. Results:The results of MSCT showed 107 occult rib fracture were detected for 73 cases patients, and about 59.81% occult rib fracture were occurred in the rib angle, and the non- fully linear fracture dominated 91.59%. The diagnostic accuracy of all the multi-dimensional reconstruction techniques used in this study were: CRP (100.0%)> MPR (97.19%)>SSD (85.89%)> VR (78.50%)> MIP (27.88%).Conclusions:The MSCT joint multi-dimensional reconstruction techniques has a speciifc diagnostic value for the occult rib fractures, MSCT combined with MSCT CRP / MPR and VR, etc. could received a ideal diagnostic accuracy.

  9. Multi-slice CT evaluation of glenoid bone loss in patients with recurrent anterior shoulder dislocation%多层螺旋CT评价复发性肩关节前方脱位的前方关节盂骨质缺损的临床意义

    崔志新; 张悦; 郑卓肇; 任阿红

    2012-01-01

    目的 在复发性肩关节前方脱位中,利用MSCT评估关节盂前方骨质缺损情况.方法 回顾分析108例复发性肩关节前脱位和12例单次肩关节脱位患者的MSCT检查,对比评价前方关节盂骨质缺损的发生率、程度及位置.利用Fisher精确概率法分析前方关节盂骨质缺损的发生率,利用Wilcoxon秩和检验比较前方关节盂骨质缺损的上下长径、深度及比例.结果 在复发性肩关节前脱位中,91.7%(99/108)存在前方关节盂的骨质缺损,缺损比例为(16.0±6.0)%,缺损中心位置介于时钟分区的2:20~ 4:25点(平均3:20点),62.0%(67/108)前方出现骨性Bankart病变,包括游离型39例(58.2%)及黏附型28例(41.8%).12例单次肩关节脱位中,9例出现前方关节盂骨质缺损,其缺损发生率(9/12;P=0.100)和缺损比例[(15.2±7.1)%;P=0.453]与复发性肩关节脱位比较差异均无统计学意义.结论 前方关节盂骨质缺损为复发性肩关节前方脱位的常见表现.%Objective To evaluate multi-slice CT (MSCT) in glenoid bone loss of patients with recurrent anterior shoulder dislocation.Methods MSCT findings of 108 patients with recurrent anterior shoulder dislocation and 12 with single anterior shoulder dislocation were retrospectively studied.The incidence,degrees and locations of glenoid bone losses were recorded.The incidence was analyzed with Fisher exact test.The maximum length,depth and proportion were compared with Wilcoxon rank sum test.Results Glenoid bone loss was detected in 91.7% (99/108)patients with recurrent anterior shoulder dislocation.The proportion of glenoid bone loss was ( 16.0 ± 6.0)%,and the central locations of glenoid bone loss were from 2: 20 to 4: 25 ( mean 3: 20).Sixty-two percent (67/108) patients had bony Bankart lesions in which 58.2% (39/67) bony fragments were free and 41.8% (28/67) were adherent to the anterior border of the glenoid cavity.Seventy-five percent (9/12) patients with single

  10. 多层螺旋CT在儿童完全性肺静脉异位引流诊断中的研究%Application of multi-slice spiral CT in diagnosis of total anomalous pulmonary venous drainage in children

    樊国峰; 赵鑫; 张小安; 叶自青; 刘晓晨

    2011-01-01

    目的:探讨多层螺旋CT在完全性肺静脉异位引流中的诊断价值.方法:回顾性分析2005年5月~2010年4月经心脏外科手术证实的30例完全性肺静脉异位引流患儿的MSCT图像特点,探讨MSCT在完全性肺静脉异位引流及并发畸形诊断中的价值,为术前诊断、手术方式选择及术后随访提供信息.结果:30例中心上型15例,心内型12例,心下型2例,混合型1例;术前经MSCT诊断为完全型28例(心上型15例,心内型10例,心下型2例,混合型1例),漏诊2例,诊断符合率为93.3%;TTE诊断心上型11例,心内型9例,心下型1例,漏诊9例,诊断符合率为70.0%.结论:多层螺旋CT.是完全性肺静脉异位引流准确、重要的检查方法.%Objective: To explore the value of multi - slice spiral CT (MSCT) in diagnosis of total anomalous pulmonary venous drainnge (TAPVD) in children.Methods: The imaging characteristics of MSCT among 30 children with TAPVD who were diagnosed definitely by department of cardiac surgery in the hospital from May 2005 to April 2010 were analyzed retrospectively, the value of MSCT in diagnosis of TAPVD combined with abnormality was explored, then the information was provided for preoperative dingnosis, choice of operative medes and postoperative follow -up.Results: The types of TAPVD among 30 children: 15 children with supra - cardiac type, 12 children with intra- cardiac type, 2 children with infra- cardiac type and 1 child with mixed type; 28 children were diagnosed as complete type by MSCT before surgery ( 15 children with supra -cardiac type, 10 children with intra -cardiac type, 2 children with infra -cardiac type and 1 child with mixed type), 2 children were missed, the diagnostic accordance rate was 93.3%.The results of TTE: 11 children with supra -cardiac type, 9 children with intra- cardiac type, 1 child with infra -cardiac type, 9 children were missed, the diagnostic accordance rate was 70.0%.Conclusion: MSCT is a accurate and important

  11. COMPUTING

    I. Fisk

    2010-01-01

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

  12. COMPUTING

    M. Kasemann

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

  13. COMPUTING

    I. Fisk

    2011-01-01

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

  14. COMPUTING

    M. Kasemann

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

  15. COMPUTING

    I. Fisk

    2012-01-01

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

  16. COMPUTING

    P. McBride

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

  17. COMPUTING

    M. Kasemann

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

  18. The optimization of low-dose scanning protocols of 64-slice spiral CT in the adult chest: a multicenter study

    Objective: To compare the image quality of chest low dose CT (LDCT) using automatic exposure control (AEC) and constant current. control (CCC) and explore a more reasonable scanning protocol. Methods: Two hundred and eighty participants were examined with 64 CT scanner at 7 centers in China. All were divided into 4 groups. Two groups underwent LDCT using AEC with standard deviation set at 25 (Al) and 30 (A2) respectively and the tube current ranged from 10 mA to 80 mA. The other two groups underwent LDCT using CCC with tube current set at 40 mA (Cl) and 50 mA (C2) respectively. The axial and MPR images were evaluated by two radiologists who were blinded to the scanning protocols. The radiation dose, noise and the image quality of the 4 groups were compared and analyzed statistically. Differences of radiation dose and noise among groups were determined with variance analysis and t test, image quality with Mann- Whitney test and the consistency of diagnosis with Kappa test. Results: There was a significant lower DLP in AEC group than in CCC group [(82.62±40.31) vs (110.81±18.21) mGy · cm (F=56.88, P 0.05]. The noisy of AEC group was higher than that of CCC group both on lung window (41.50±9.58 vs 40.86±7.03) and mediastinum window (41.19±7.83 vs 40.92±9.89), but there was no significant difference (Flung=0.835, P=0.476, Fwediastinum=1.910, P=0.128). The quality score of axial image in AEC group was higher than that in CCC group (superior margin of the brachiocephalic vein level: 4.49± 0.56 vs 4.38±0.64, superior margin of the aortic arch: 4.86±0.23 vs 4.81±0.32, the right superior lobar bronchus Level: 4.87±0.27 vs 4.84±0.22, the right middle lobar bronchus Level: 4.90±0.25 vs 4.88±0.21) except on the right inferior pulmonary vein level (4.92±0.25 vs 4.93±0.17) and superior margin of the left diaphragmatic dome level (4.91±0.27 vs 4.93±0.22) on lung window, but no significant differences (F=0.076-1.748, P>0.05) were observed. A significant higher score in AEC group was observed on mediastinum window compared with CCC group on superior margin of' brachiocephalic vein level (2.57±0.77 vs 2.46±0.59, F=8.459, P0.05). The MPR image quality of AEC group was better than that of CCC group both on lung window and mediastinum window (Zlung=-2.258, Zmediastinum=-1.330, P>0.05). For all participants including the underweighted group, the normal group and the overweighted group, the image quality of Al group was better than that of A2 group without significant differences (the underweighted group: Zlung= 0.000, P=1.000, Zmediastinum=0.000, P=1.000; the normal group: Zlung=-0.062, P= 0.950, Zmediastinum=-0.746, P=0.456; the overweighted group: Zlung=-1.177, P=0.239, Zmediastinum=-1.715, P=0.144) both on lung and mediastinum windows, and for the higher BMI participants, a better image quality was obtained in Al group than in A2 group on the mediastinum window (Z=-1.715, P=0.144). Conclusions: The total radiation exposure dose of AEC group is significantly lower than that of CCC group, but no statistical significant differences are observed between both groups in image quality and noise level. The AEC technique is highly recommended in thoracic LDCT scan for screening program, and the SD25 (SD value =25) scan protocol is suggested for higher BMI population while the SD30 (SD value = 30) scan protocol for lower BMI population. (authors)

  19. Normal kidney size and its influencing factors - a 64-slice MDCT study of 1.040 asymptomatic patients

    Rehder Peter

    2009-12-01

    Full Text Available Abstract Background Normal ultrasound values for pole-to-pole kidney length (LPP are well established for children, but very little is known about normal kidney size and its influencing factors in adults. The objectives of this study were thus to establish normal CT values for kidney dimensions from a group of unselected patients, identify potential influencing factors, and to estimate their significance. Methods In multiphase thin-slice MDCTs of 2.068 kidneys in 1.040 adults, the kidney length pole to pole (LPP, parenchymal (PW and cortical width (CW, position and rotation status of the kidneys, number of renal arteries, pyelon width and possible influencing factors that can be visualized, were recorded from a volume data set. For length measurements, axes were adjusted individually in double oblique planes using a 3D-software. Analyses of distribution, T-tests, ANOVA, correlation and multivariate regression analyses were performed. Results LPP was 108.5 ± 12.2 mm for the right, and 111.3 ± 12.6 mm for the left kidney (p Conclusions Due to the complex influences on kidney size, assessment should be made individually. The most important influencing factors are BMI, height, gender, age, position of the kidneys, stenoses and number of renal arteries.

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

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

  1. COMPUTING

    P. MacBride

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

  2. COMPUTING

    Matthias Kasemann

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

  3. COMPUTING

    M. Kasemann

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

  4. COMPUTING

    Contributions from I. Fisk

    2012-01-01

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

  5. COMPUTING

    I. Fisk

    2012-01-01

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

  6. COMPUTING

    I. Fisk

    2013-01-01

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

  7. COMPUTING

    2010-01-01

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

  8. COMPUTING

    I. Fisk

    2011-01-01

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

  9. COMPUTING

    M. Kasemann

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

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

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

    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.

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

    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

  12. 不同影像学方法对胰腺癌T、N、M分期及可切除性的评估%Prospective evaluation of ultrasonography, multi-slice spiral CT, endoscopic ultrasonography, and magnetic resonance imaging in assessment of TNM staging and assessment of resectibility in pancreatic carcinoma

    田艳涛; 曲辉; 赵平; 王成锋; 单毅; 赵东兵; 王贵齐; 赵心明; 欧阳汉; 郝玉芝; 孙跃民

    2008-01-01

    目的 前瞻性评估超声(US)、多层螺旋CT(MSCT)、内镜超声(EUS)和核磁共振(MRI)在胰腺癌T、N、M分期及可切除性的预测价值.方法 对68例胰腺癌分别进行超声(US)、螺旋CT(MSCT)、核磁共振(MRI)、超声内镜(EUS)检查,评估其在T、N、M分期和可切除性与手术病理结果比较及临床意义.结果 EUS对肿瘤大小的独立预测效果最好,最大径回归系数和最小径回归系数分别为1.025(P=0.043)和0.987(P<0.0001);在对淋巴结转移的评估中,EUS具有最高的敏感性(75.0%)、准确性(87.5%)和阴性预测价值(91.7%),单元Logistic回归显示与外科发现有显著相关性(OR值:33.00,95%CI:7.18~151.77 P<0.0001),且多元Logistic回归分析证实EUS具独立预测价值(OR值:34.50,95%CI:6.54~182.09,P<0.0001).MSCT评估远处转移具最高敏感性88.9%,其对胰腺癌术前TNM分期准确率最高,为61.8%.4种方法对胰腺癌可切除性的判断均与手术结果具有相关性,但多元回归分析尚无一种影像学检查具有独立预测价值.结论 MSCT对胰腺癌的TNM分期准确性最高,EUS评估肿瘤大小和淋巴结转移效果最好,对胰腺癌的术前评估尚需要两种以上的方法联合应用.%Objective To evaluate prospectively the efficacy and clinical significance of ultrasonography(US), multi-slice spiral CT (MSCT) , magnetic resonance imaging (MRI) , and endoscopic ultrasonography (EUS) in assessment of the TNM staging and resectibility of pancreatic carcinoma. Methods Consecutive 68 patients with pancreatic carcinoma underwent US, MSCT, MRI, and EUS to assess their efficacies in assessment of the size of carcinoma, lymph node metastasis, and distant metastasis. The results of theses imaging techniques were compared with the surgical and pathological findings. Results EUS was the most precise technique in evaluating the T staging of pancreatic carcinoma with the coefficients of regression of maximum and minimum radiuses of 1. 025 (P=0

  13. Choice of surgical procedures based on combined assessment of 64 multi-slice spiral computer tomography and fibrinogen levels in treatment of colon cancer%64排多层螺旋CT和纤维蛋白原联合评估结肠癌对手术方案选择的影响

    张琼文; 吕东昊; 邰阳; 汪晓东; 李立

    2010-01-01

    目的 探讨64排多层螺旋CT(MSCT)和纤维蛋白原(FIB)联合术前评估结肠癌对手术方案选择的影响.方法 前瞻性纳入130例结肠癌患者,随机均分为A组和B组,A组术前行MSCT和FIB联合评估,B组只进行MSCT评估,将术前分期和预测手术方案分别与术后病理分期和实际手术方案比较.结果 实际纳入病例120例,A组60例,B组60例.2组基线情况一致.A组术前T、N、M及TNM分期的准确度分别为76.7%、78.3%、98.3%和78.3%;B组术前分别为76.7%、56.7%、96.7%和58.3%.2组在N、TNM分期之间的差异有统计学意义.A组手术预测符合率为98.3%,B组为80.0%,2组差异具有统计学意义(P=0.001). 结论 MSCT和FIB联合评估结肠癌患者的策略可以提高术前分期的准确性的同时显著提高手术预测方案的符合率.

  14. The prevalence of undiagnosed abnormalities on non-contrast-enhanced computed tomography compared to contrast-enhanced computed tomography of the brain

    Cornelia Minné

    2014-04-01

    Full Text Available Background: Even though magnetic resonance imaging (MRI is the gold standard investigation for intracranial pathology, it is not widely available in developing countries and computed tomography (CT of the brain remains the first-line investigation for patients with suspected intracranial pathology. It is generally accepted that certain intracranial pathology can be missed on non-contrast-enhanced CT (NECT of the brain if a contrast-enhanced CT (CECT is not done. We have to consider on the one hand the risk of delayed or missed diagnosis and on the other hand the cost, increased radiation exposure and contrast-induced reactions. Advances in CT technology have also improved the resolution of CT scan images, making it easier to identify pathology on an NECT of the brain. To date, no study comparing NECT to CECT of the brain, utilising 64-slice CT technology, has been published.Objectives: To determine the prevalence of undiagnosed abnormalities on non-contrast-enhanced computed tomography (NECT scans of the brain reported as normal, on a 64-slice CT scanner.Method: A descriptive retrospective study was undertaken of CT brain scans done during a 12-month period at a tertiary provincial hospital in the Northern Tshwane district of Gauteng, South Africa. The CT brain scans were evaluated by three reviewers (general radiologists. The NECT and contrast-enhanced computed tomography (CECT scans of the brain were reviewed independently on separate occasions. Reviewers were blinded to patient history, each other’s interpretation, and to their own interpretation of the NECT when evaluating the CECT and vice versa. Discrepancies in interpretation were resolved during a consensus meeting between all three reviewers. The reviewers also re-evaluated the NECT scans of the cases with undiagnosed abnormal findings during this session. A decision was made pertaining to the visibility of the abnormal findings on the NECT scan.Results: In this study, 3.28% of cases

  15. Evaluation of myocardial bridge with multidetector computed tomography

    The myocardial bridge (MB) is an intramural segment of coronary artery that is covered with myocardial tissue. The current diagnostic methods are coronary angiography, intravascular ultrasound and intracoronary Doppler, which are all invasive modalities. In this study, multidetector computed tomography (MDCT) was used to detect and evaluate the anatomical properties of the MB. The 607 patients with suspected or known coronary artery disease underwent 64-slice MDCT. MB was diagnosed when an intramural segment of coronary artery was visualized on axial and multiplanar reconstruction images. The prevalence, length, myocardial thickness, and location were evaluated. Of the 607 patients, 39 (6.42%) had a MB. In 20 patients (52.6%), the MB was located in the mid left anterior descending artery. The length of tunneled artery was a mean 16.3 mm, from 6.9 mm to 30 mm, and the maximum thickness of the myocardial tissue was between 0.5 mm and 3.9 mm, with a mean of 1.8 mm. The length of the MB correlated significantly with thickness (P=0.049). The incidence of MB and its anatomical properties can be evaluated with MDCT, which might be a useful and noninvasive method of detecting this variant. (author)

  16. Computer-assisted 3-dimensional anthropometry of the scaphoid.

    Pichler, Wolfgang; Windisch, Gunther; Schaffler, Gottfried; Heidari, Nima; Dorr, Katrin; Grechenig, Wolfgang

    2010-02-01

    Scaphoid fracture fixation using a cannulated headless compression screw and the Matti-Russe procedure for the treatment of scaphoid nonunions are performed routinely. Surgeons performing these procedures need to be familiar with the anatomy of the scaphoid. A literature review reveals relatively few articles on this subject. The goal of this anatomical study was to measure the scaphoid using current technology and to discuss the findings with respect to the current, relevant literature.Computed tomography scans of 30 wrists were performed using a 64-slice SOMATOM Sensation CT system (resolution 0.6 mm) (Siemens Medical Solutions Inc, Malvern, Pennsylvania). Three-dimensional reconstructions from the raw data were generated by MIMICS software (Materialise, Leuven, Belgium). The scaphoid had a mean length of 26.0 mm (range, 22.3-30.7 mm), and men had a significantly longer (Pscaphoid than women (27.861.6 mm vs 24.561.6 mm, respectively). The width and height were measured at 3 different levels for volume calculations, resulting in a mean volume of 3389.5 mm(3). Men had a significantly larger (Pscaphoid volume than women (4057.86740.7 mm(3) vs 2846.56617.5 mm(3), respectively).We found considerable variation in the length and volume of the scaphoid in our cohort. We also demonstrated a clear correlation between scaphoid size and sex. Surgeons performing operative fixation of scaphoid fractures and corticocancellous bone grafting for nonunions need to be familiar with these anatomical variations. PMID:20192143

  17. Ruptured ectopic pregnancy diagnosed with computed tomography

    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

  18. 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.

    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

  19. [Phantom Study on Dose Reduction Using Iterative Reconstruction in Low-dose Computed Tomography for Lung Cancer Screening].

    Minehiro, Kaori; Takata, Tadanori; Hayashi, Hiroyuki; Sakuda, Keita; Nunome, Haruka; Kawashima, Hiroko; Sanada, Shigeru

    2015-12-01

    We investigated dose reduction ability of an iterative reconstruction technology for low-dose computed tomography (CT) for lung cancer screening. The Sinogram Affirmed Iterative Reconstruction (SAFIRE) provided in a multi slice CT system, Somatom Definition Flash (Siemens Healthcare) was used. An anthropomorphic chest phantom (N-1, Kyoto Kagaku) was scanned at volume CT dose index (CTDIvol) of 0.50-11.86 mGy with 120 kV. For noise (standard deviation) and contrast-to-noise ratio (CNR) measurements, CTP486 and CTP515 modules in the Catphan (The Phantom Laboratory) were scanned. Radiological technologists were participated in the perceptual comparison. SAFIRE reduced the SD values by approximately 50% compared with filter back projection (FBP). The estimated dose reduction rates by SAFIRE determined from the perceptual comparison was approximately 23%, while 75% dose reduction rate was expected from the SD value reduction of 50%. PMID:26685831

  20. A comparison of perfusion computed tomography and contrast enhanced computed tomography on radiation target volume delineation using rabbit VX2 brain tumor model

    Objective: To compare the accuracy of blood volume perfusion imaging (perfusion CT)with contrast enhanced 64-slice spiral computed tomography (CECT) in the evaluation of gross tumor volume (GTV) and clinical target volume (CTV) using rabbits with VX2 brain tumor. Methods: Perfusion CT and CECT were performed in 20 rabbits with VX2 brain tumor. The GTV and CTV calculated with the maximal and minimal diameter of each tumor in the blood volume (BV) maps and CECT were measured and compared to those in pathological specimens. Results: The mean value of the maximal and minimal diameter of GTV was (8.19 ± 2.29) mm and (4.83 ± 1.31) mm in pathological specimens, (11.98 ±3.29) mm and (7.03±1.82) mm in BV maps, while (6.36±3.85) mm and (3.17±1.93) mm in CECT images, which were significantly different (pathological specimen vs. BV map, t = 7.17, P =0.000;pathological specimen vs. CECT, t = 8.37, P = 0.000, respectively). The mean value of the maximal and minimal diameter of CTV in pathologic specimens was (12.87 ± 3.74) mm and (7.71 ± 2.15) mm, which was significantly different from that of GTV and CTV in CECT (t = - 3. 18, P = 0. 005 and t = - 4.24, P =0.000; t= -11.59,P=0.000 and t= -9.39, P=0.000), while similar with that of GTV in BV maps (t = - 1.95,P = 0. 067; t = - 2. 06, P = 0. 054). For CECT, the margin from GTV to CTV was 81.83% ±40.33% for the maximal diameter and 276.73% ± 131.46% for the minimal. While for BV maps, the margin was 7.93% ± 17. 84% and 12.52% ± 27. 83%, which was significant different from that for CECT images (t=7.36, P=0. 000 and t= -8.78, P=0.000). Conclusions: Compared with CECT, the BV map from 64-slice spiral CT perfusion imaging might have higher accuracy in target volume delineation for brain tumor. (authors)

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

    Ghita, Monica

    . Results were compared against organ dose measurements previously obtained at Shands UF. Important dose reductions were assessed for the broad beam volumetric acquisition of this new scanner when compared to the standard 64-slice helical protocols.

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

    The present data show a global increase in the rate of cardiovascular disease. Cardiac CT angiography has developed as a fast and non-invasive cardiac imaging modality following the introduction of multi-slice computed tomogaraphy. The aim of this study was to measure the radiation dose to the thyroid and pelvis regions in patients undergoing cardiac CT angiography using the Care Dose 4D method of 64-slice scanner. Eighty-one patients (41 males and 40 females) who were diagnosed with suspected coronary artery disease and were referred to Golestan Hospital, Imaging Department were recruited. Inclusion criteria were based on the protocol of multi-slice CT coronary angiography. The radiation dose to the thyroid and pelvis regions was measured using thermo luminescent dosimeters (TLDs). The mean radiation dose to the thyroid in male and female subjects was 0.32 mSv and 0.41 mSv, respectively (P = 0.032) (total mean, 0.36 mSv). The mean radiation dose to the pelvis in male and female subjects was 81 μSv and 112 μSv, respectively (P = 0.026) (total mean, 96.5 μSv), The total mean radiation dose to the thyroid and gonads was 0.36 mSv, and 96.5 μSv, respectively for the subjects. These values were high for one organ in a single study. Gender can affect the radiation dose to the thyroid and gonads. This can be attributed to the anatomical characteristic differences of the male and female subjects

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

    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.

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

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

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

    Jodocy, Daniel, E-mail: daniel.jodocy@klinikum-minden.de [Department of Internal Medicine III (Cardiology), Medical University of Innsbruck, Anichstraße 35, A-6020 Innsbruck (Austria); Abbrederis, Susanne, E-mail: susanne.abbrederis@uki.at [Department of Internal Medicine II (Gastroenterology and Hepatology), Medical University of Innsbruck, Anichstraße 35, A-6020 Innsbruck (Austria); Graziadei, Ivo W., E-mail: ivo.graziadei@i-med.ac.at [Department of Internal Medicine II (Gastroenterology and Hepatology), Medical University of Innsbruck, Anichstraße 35, A-6020 Innsbruck (Austria); Vogel, Wolfgang, E-mail: wolfgang.vogel@uki.at [Department of Internal Medicine II (Gastroenterology and Hepatology), Medical University of Innsbruck, Anichstraße 35, A-6020 Innsbruck (Austria); Pachinger, Otmar, E-mail: otmar.pachinger@uki.at [Department of Internal Medicine III (Cardiology), Medical University of Innsbruck, Anichstraße 35, A-6020 Innsbruck (Austria); Feuchtner, Gudrun M., E-mail: gudrun.feuchtner@i-med.ac.at [Department of Radiology, Medical University of Innsbruck, Anichstraße 35, A-6020 Innsbruck (Austria); Jaschke, Werner, E-mail: werner.jaschke@i-med.ac.at [Department of Radiology, Medical University of Innsbruck, Anichstraße 35, A-6020 Innsbruck (Austria); Friedrich, Guy, E-mail: guy.friedrich@uki.at [Department of Internal Medicine III (Cardiology), Medical University of Innsbruck, Anichstraße 35, A-6020 Innsbruck (Austria)

    2012-09-15

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

  6. Determination of dosimetric quantities in pediatric abdominal computed tomography scans*

    Jornada, Tiago da Silva; da Silva, Teógenes Augusto

    2014-01-01

    Objective Aiming at contributing to the knowledge on doses in computed tomography (CT), this study has the objective of determining dosimetric quantities associated with pediatric abdominal CT scans, comparing the data with diagnostic reference levels (DRL). Materials and methods The study was developed with a Toshiba Asteion single-slice CT scanner and a GE BrightSpeed multi-slice CT unit in two hospitals. Measurements were performed with a pencil-type ionization chamber and a 16 cm-diameter polymethylmethacrylate trunk phantom. Results No significant difference was observed in the values for weighted air kerma index (CW), but the differences were relevant in values for volumetric air kerma index (CVOL), air kerma-length product (PKL,CT) and effective dose. Conclusion Only the CW values were lower than the DRL, suggesting that dose optimization might not be necessary. However, PKL,CT and effective dose values stressed that there still is room for reducing pediatric radiation doses. The present study emphasizes the importance of determining all dosimetric quantities associated with CT scans. PMID:25741103

  7. Determination of dosimetric quantities in pediatric abdominal computed tomography scans

    Jornada, Tiago da Silva [Universidade Federal de Sao Paulo (UNIFESP), Sao Paulo, SP (Brazil). Escola Paulista de Medicina. Dept. de Diagnostipo por Imagem; Silva, Teogenes Augusto da, E-mail: silvata@cdtn.br [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

    2014-09-15

    Objective: aiming at contributing to the knowledge on doses in computed tomography (CT), this study has the objective of determining dosimetric quantities associated with pediatric abdominal CT scans, comparing the data with diagnostic reference levels (DRL). Materials and methods: the study was developed with a Toshiba Asteion single-slice CT scanner and a GE BrightSpeed multi-slice CT unit in two hospitals. Measurements were performed with a pencil-type ionization chamber and a 16 cm-diameter polymethylmethacrylate trunk phantom. Results: No significant difference was observed in the values for weighted air kerma index (C{sub W}), but the differences were relevant in values for volumetric air kerma index (C{sub VOL}), air kerma-length product (P{sub KL,CT}) and effective dose. Conclusion: Only the CW values were lower than the DRL, suggesting that dose optimization might not be necessary. However, P{sub KL,CT} and effective dose values stressed that there still is room for reducing pediatric radiation doses. The present study emphasizes the importance of determining all dosimetric quantities associated with CT scans. (author)

  8. Computed tomography of the vesicular glands: anatomical animal model (Oryctolagus cuniculus)

    Spiral CT is a non-invasive imaging method of choice for animal anatomical studies. The aim of the study was to establish the imaging anatomical features of the vesicular glands in the rabbit. Eight sexually mature healthy clinically male New Zealand rabbits of 18 months of age with body weight from 2.8 kg to 3.2 kg were used. The animals were anesthetized. As contrast medium Opti-ray350 was administrated. The computed tomography scan was complied with certain bone and soft tissue markers. For this purpose, a whole body multi-slice spiral computed tomography scanner was used. The both soft tissue glands were heterogeneous and relatively hyperdense structures, and defined in detail from the adjacent soft tissues. The urinary bladder neck was ventrally to the glands. Both vesicular glands were better differentiated each other when the rabbit is examined in abdominal recumbence. In dorsal recumbence the shape of the transversal image of the glandular finding was oval. In abdominal recumbence both the left and right soft tissue vesicular gland were defined. Transversal anatomical computed tomographic investigation of the rabbit vesicular gland is a detailed and definitive method, to study the normal morphology of these glands. Key words: Vesicular Gland. Helical Computed Tomography. Anatomy. Rabbit

  9. Planning deep inferior epigastric perforator flaps for breast reconstruction: a comparison between multidetector computed tomography and magnetic resonance angiography

    Cina, A.; Rinaldi, P.; Cipriani, A.; Bonomo, L. [Agostino Gemelli Hospital, Catholic University of Sacred Heart, Department of Radiological Sciences, Rome (Italy); Barone-Adesi, L.; Salgarello, M. [Agostino Gemelli Hospital, Catholic University of Sacred Heart, Department of Surgery, Plastic and Reconstructive Surgery Unit, Rome (Italy); Masetti, R. [Agostino Gemelli Hospital, Catholic University of Sacred Heart, Department of Surgery, Breast Surgery Unit, Rome (Italy)

    2013-08-15

    Deep inferior epigastric perforator (DIEP) flaps have become the state of the art in breast reconstruction. We compared the diagnostic performance of multidetector computed tomography (CTA) and magnetic resonance angiography (MRA) in DIEP flap planning. Twenty-three women (mean age 48.0 years, range 26-72 years) underwent preoperative blinded evaluation using 64-slice CTA and 1.5-T MRA. Perforator identification, measurement of their calibre, intramuscular course (IMC), assessment of direct venous connections (DVC) with main superficial veins, superficial venous communications (SVC) between the right and left hemi-abdomen and deep inferior epigastric artery (DIEA) branching type were performed. Surgery was carried out by the same team. Intraoperative findings were the standard of reference. Accuracy in identifying dominant perforators was 91.3 % for both techniques and mean error in calibre measurement 1.18 {+-} 0.35 mm for CTA and 1.63 {+-} 0.39 mm for MRA. Accuracy in assessing perforator IMCs was 97.1 % for CTA and 88.4 % for MRA, DVC 94.4 % for both techniques, SVC 91.3 % as well, and DIEA branching type 100 % for CTA and 91.3 % for MRA. Image acquisition and interpretation time was 21 {+-} 3 min for CTA (35 {+-} 5 min for MRA). In a strategy to optimise DIEP flap planning avoiding radiation exposure, MRA can be proposed alternatively to CTA. (orig.)

  10. Planning deep inferior epigastric perforator flaps for breast reconstruction: a comparison between multidetector computed tomography and magnetic resonance angiography

    Deep inferior epigastric perforator (DIEP) flaps have become the state of the art in breast reconstruction. We compared the diagnostic performance of multidetector computed tomography (CTA) and magnetic resonance angiography (MRA) in DIEP flap planning. Twenty-three women (mean age 48.0 years, range 26-72 years) underwent preoperative blinded evaluation using 64-slice CTA and 1.5-T MRA. Perforator identification, measurement of their calibre, intramuscular course (IMC), assessment of direct venous connections (DVC) with main superficial veins, superficial venous communications (SVC) between the right and left hemi-abdomen and deep inferior epigastric artery (DIEA) branching type were performed. Surgery was carried out by the same team. Intraoperative findings were the standard of reference. Accuracy in identifying dominant perforators was 91.3 % for both techniques and mean error in calibre measurement 1.18 ± 0.35 mm for CTA and 1.63 ± 0.39 mm for MRA. Accuracy in assessing perforator IMCs was 97.1 % for CTA and 88.4 % for MRA, DVC 94.4 % for both techniques, SVC 91.3 % as well, and DIEA branching type 100 % for CTA and 91.3 % for MRA. Image acquisition and interpretation time was 21 ± 3 min for CTA (35 ± 5 min for MRA). In a strategy to optimise DIEP flap planning avoiding radiation exposure, MRA can be proposed alternatively to CTA. (orig.)

  11. Evaluation of the Correlation Between Myocardial Bridging and Atherosclerotic Changes in Coronary Artery Segment Proximal to the Bridge by 64-Slice Multidetector CT Scan

    Safa Hoodeshenas; Abbas Arjmand Shabestari

    2011-01-01

    Background/Objective: The aim of this study was"nto evaluate the prevalance and characteristics of myocardial bridging (MB) and to assess the correlation"nbetween atherosclerosis and MB."nMaterials and Methods: Retrospective evaluation"nof 2790 coronary angiograms were obtained by 64-"nslice multidetector CT. The prevalance, length, depth,"nprecise of MB location and concomitant atherosclerosis"nproximal to tunneled segment were evaluated. The"ngroup of...

  12. Evaluation of the Correlation Between Myocardial Bridging and Atherosclerotic Changes in Coronary Artery Segment Proximal to the Bridge by 64-Slice Multidetector CT Scan

    Safa Hoodeshenas

    2011-05-01

    Full Text Available Background/Objective: The aim of this study was"nto evaluate the prevalance and characteristics of myocardial bridging (MB and to assess the correlation"nbetween atherosclerosis and MB."nMaterials and Methods: Retrospective evaluation"nof 2790 coronary angiograms were obtained by 64-"nslice multidetector CT. The prevalance, length, depth,"nprecise of MB location and concomitant atherosclerosis"nproximal to tunneled segment were evaluated. The"ngroup of subjects with MB was compared with the"ncontrol group (subjects without MB."nResults: Of the 2790 subjects, 548 (19.64% were"nfound to have MB. MB was present equally in men"nand women. The tunneled segment was intact in"nall subjects. A negative significant correlation was"nfound between the presence of MB and severity of"natherosclerosis in the proximal segment of the coronary"nartery (p<0.001; df=2×2=42.75. The mid LAD was the"nmost common coronary artery involved. The severity"nof atherosclerosis in the part proximal to the tunneled"nsegment correlated with the thickness of bridge"n(p=0.035, but no significant correlation was found"nwith the length of the bridged segment (p=0.431."nConclusion: The myocardial bridge not only does not"npredispose to the development of atherosclerosis in"nthe coronary artery segment proximal to the bridge,"nbut may also be a protective factor.

  13. 64排螺旋CT血管成像诊断永存三叉动脉%Diagnosis of persistent trigeminal artery with 64-slice spiral CT angiography

    袁飞; 刘银社; 赵军; 谷鹏; 顾欣; 冯凯琳

    2010-01-01

    目的 观察64排螺旋CT血管成像(CTA)在诊断永存三叉动脉(PTA)中的价值,提高对该血管变异的认识.方法 回顾性分析2734例行头颈64排螺旋CTA检查中的5例PTA患者的影像学资料,分析PTA的发生率、起源、走行、后循环供血及合并其他血管畸形的情况.结果 ①PTA的发生率为0.18%(5/2734),其中3例位于右侧,2例位于左侧.②三叉动脉均起自颈内动脉海绵窦段,血管走行外侧型4例,内侧型1例;按Saltzman分型显示PTA后循环供血情况:Ⅰ型1例,Ⅱ型1例,Ⅲ型3例.③吻合点近端的基底动脉及双侧椎动脉发育不良3例,吻合点近端基底动脉完全萎缩1例;合并PTA的动脉瘤1例,合并对侧大脑中动脉成窗1例.结论 64排CTA能清晰、快速、无创、准确地显示PTA及其走行.在鞍区或鞍上区手术及介入治疗前,了解这种异常血管的有助于制定合理的手术和介入治疗方案,避免因操作不当所致的危险.

  14. 64排螺旋CT血管造影诊断颅内动脉瘤%DIAGNOSIS OF INTRACRANIAL ANEURYSM WITH 64-SLICE SPIRAL CT ANGIOGRAPHY

    钱惠农; 王有刚; 朱蕴杰; 姜峰

    2009-01-01

    [目的]评估64排螺旋CT血管造影(CTA)在颅内动脉瘤诊断中的作用.[方法]对48例自发性蛛网膜下腔出血(SAH)患者进行CTA检查,同期行数字减影血管造影(DSA),分析比较两种检查的结果.[结果]11例SAH患者其CTA和DSA均未见异常.37例CTA和DSA结果存在异常患者中,CTA发现37个动脉瘤,DSA发现38个(2例多发性动脉瘤),CTA遗漏2个动脉瘤,误诊1个动脉瘤.CTA诊断动脉瘤的灵敏度为94.7%,特异度为91.7%.[结论]64排螺旋CTA是诊断颅内动脉瘤的一种简单、快速、准确的方法,具有极高的临床价值.

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

    Bagheri, Mohammadhadi, E-mail: Bagherimh@gmail.com [Department of Radiology, Shiraz University of Medical Sciences, Namazi Hospital, Shiraz (Iran, Islamic Republic of); Hajati, Azadeh, E-mail: azadeh.hajati@gmail.com [Department of Radiology, Shiraz University of Medical Sciences, Namazi Hospital, Shiraz (Iran, Islamic Republic of); Hosseini, Mohammadkazem, E-mail: hosseiniaslm@sums.ac.ir [Department of Radiology, Shiraz University of Medical Sciences, Namazi Hospital, Shiraz (Iran, Islamic Republic of); Ostad, Seyed Pouria, E-mail: Pouria.Ostad@gmail.com [Department of Radiology, Shiraz University of Medical Sciences, Namazi Hospital, Shiraz (Iran, Islamic Republic of)

    2012-09-15

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

  16. Infant Cardiac CT Angiography with 64-Slice and 256-Slice CT: Comparison of Radiation Dose and Image Quality Using a Pediatric Phantom

    Lee, Yi-Wei; Yang, Ching-Ching; Mok, Greta S. P.; Wu, Tung-Hsin

    2012-01-01

    Background The aims of this study were to investigate the image quality and radiation exposure of pediatric protocols for cardiac CT angiography (CTA) in infants under one year of age. Methodology/Principal Findings Cardiac CTA examinations were performed using an anthropomorphic phantom representing a 1-year-old child scanned with non-electrocardiogram-gated (NG), retrospectively electrocardiogram-gated helical (RGH) and prospectively electrocardiogram-gated axial (PGA) techniques in 64-slic...

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

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

  18. Visualisation of the temporary cavity by computed tomography using contrast material.

    Schyma, Christian; Hagemeier, Lars; Greschus, Susanne; Schild, Hans; Madea, Burkhard

    2012-01-01

    The temporary cavity of a missile produces radial tears in ordnance gelatine, which correlate to the energy transfer. Computed tomography is a useful and non-destructive method to examine gelatine blocks. However, the tears give only few radiocontrast by air filling, which decreases with the time past shooting. Therefore, systematically, a radiocontrast material was searched to enhance the contrast. Different contrast materials were amalgamated to acryl paint, and about 7 g was sealed in a foil bag, which was integrated in the front of a standard 10% gelatine cylinder. Shots with Action-5 expanding bullets were performed from a 5-m distance. Gelatine was scanned by multi-slice computed tomography. The multiplanar reconstructed images were compared to mechanically cut slices of 1 cm thickness. It was shown experimentally that iodine containing water-soluble contrast material did not give sufficient contrast and caused diffusion artefacts. Best results were obtained by barium sulphate emulsion. The amount of acryl paint was sufficient to colour the tears for optical scanning. The radiocontrast of barium leads to satisfying imaging of tears and allowed the creation of a three-dimensional reconstruction of the temporary cavity. Comparison of optical and radiological results showed an excellent correlation, but absolute measures in computed tomographic (CT) images remained lower compared with optically gathered values in the gelatine slices. Combination of paint and contrast material for CT examination will facilitate the evaluation of complex ballistic models and increase accuracy. PMID:21437598

  19. Cine CT: a new technology for cardiac computed tomography

    The technical requirements for adequate evaluation of cardiac anatomy and physiology, namely scan speeds in the 33-100 msec range, simultaneous multi-slice capability, 15-20 multi-level scans/second and a repeat multi-slice study at one per second, have been realized with the inception of the Cine-CT scanner. This scanner acquires scan data in 50 milliseconds by eliminating moving parts and using a scanning electron beam to produce a high speed X-ray source. The authors describe this scanner and the three scanning modes available: continuous or cine mode; flow or triggered mode; and full resolution mode. (Auth.)

  20. The application and advantages of multi-slice CT in the diagnosis of myocardial bridging

    Objective: To investigate the ability of electrocardiogram-gated multislice CT (MSCT) in the diagnosis of myocardial bridging. Methods: Fifty-one patients (82 coronary arteries) with suspected coronary artery disease underwent multi-detector row CT, conventional coronary angiography and intravascular ultrasonography as well. The sensitivity, specificity and accuracy of MSCT for the detection of myocardial bridging were determined. The interobserver agreement was calculated by using Cohen's Kappa test. Results: A total of 26 tunneled arteries exclusively located near the middle segment of left anterior descending coronary artery were found by coronary angiography and intravascular ultrasonography. Compared to the invasive methods, MSCT correctly detected 23 of 26 myocardial bridges with a sensitivity of 88% (23/26), specificity of 96% (52/54) and accuracy of 94% (75/80). The Kappa value for overall interobserver variation was 0. 62. Two myocardial bridges diagnosed by MSCT were missed with the invasive method. With the results of invasive and non-invasive methods combined as the standard of reference, the overall sensitivity, specificity, and accuracy of MSCT in detecting myocardial bridging were 89% (25/28) , 91% (21/23), and 90% (46/51), respectively. Conclusion: As a non-invasive imaging modality, MSCT is feasible and reliable in the detection of myocardial bridging. (authors)

  1. Multi-slice to volume registration of ultrasound data to a statistical atlas of human pelvis

    Ghanavati, Sahar; Mousavi, Parvin; Fichtinger, Gabor; Foroughi, Pezhman; Abolmaesumi, Purang

    2010-02-01

    Identifying the proper orientation of the pelvis is a critical step in accurate placement of the femur prosthesis in the acetabulum in Total Hip Replacement (THR) surgeries. The general approach to localize the orientation of the pelvis coordinate system is to use X-ray fluoroscopy to guide the procedure. An alternative can be employing intra-operative ultrasound (US) imaging with pre-operative CT scan or fluoroscopy imaging. In this paper, we propose to replace the need of pre-operative imaging by using a statistical shape model of the pelvis, constructed from several CT images. We then propose an automatic deformable intensity-based registration of the anatomical atlas to a sparse set of 2D ultrasound images of the pelvis in order to localize its anatomical coordinate system. In this registration technique, we first extract a set of 2D slices from a single instance of the pelvic atlas. Each individual 2D slice is generated based on the location of a corresponding 2D ultrasound image. Next, we create simulated ultrasound images out of the 2D atlas slices and calculate a similarity metric between the simulated images and the actual ultrasound images. The similarity metric guides an optimizer to generate an instance of the atlas that best matches the ultrasound data. We demonstrated the feasibility of our proposed approach on two male human cadaver data. The registration was able to localize a patient-specific pelvic coordinate system with origin translation error of 2 mm and 3.45 mm, and average axes rotation error of 3.5 degrees and 3.9 degrees for the two cadavers, respectively.

  2. Dosimetric assessments multi-slice CT of the chest and abdomen in pediatrics

    The objective of this study is the dosimetry evaluation in pediatric MSCT of thorax and abdomen, and the estimation of effective dose in the different ranges of age taking into account the new ICRP recommendations, by variations that may be involved in explorations that affect breast. (Author)

  3. Whole-body diffusion imaging applying simultaneous multi-slice excitation

    Kenkel, David; Wurning, M.C.; Filli, L.; Ulbrich, E.J.; Boss, A. [Universitaetsspital Zuerich (Switzerland). Diagnostische und Interventionelle Radiologie; Runge, V.M. [Univ. Hospital Zurich (Switzerland). Dept. of Neuroradiology; Beck, T. [Siemens Healthcare GmbH, Erlangen (Germany)

    2016-04-15

    The purpose of this study was to examine the feasibility of a fast protocol for whole-body diffusion-weighted imaging (WB-DWI) using a slice-accelerated echo-planar sequence, which, when using comparable image acquisition parameters, noticeably reduces measurement time compared to a conventional WB-DWI protocol. A single-shot echo-planar imaging sequence capable of simultaneous slice excitation and acquisition was optimized for WB-DWI on a 3 T MR scanner, with a comparable conventional WB-DWI protocol serving as the reference standard. Eight healthy individuals and one oncologic patient underwent WB-DWI. Quantitative analysis was carried out by measuring the apparent diffusion coefficient (ADC) and its coefficient of variation (CV) in different organs. Image quality was assessed qualitatively by two independent radiologists using a 4-point Likert scale. Using our proposed protocol, the scan time of the WB-DWI measurement was reduced by up to 25.9 %. Both protocols, the slice-accelerated protocol and the conventional protocol, showed comparable image quality without statistically significant differences in the reader scores. Similarly, no significant differences of the ADC values of parenchymal organs were found, whereas ADC values of brain tissue were slightly higher in the slice-accelerated protocol. It was demonstrated that slice-accelerated DWI can be applied to WB-DWI protocols with the potential to greatly reduce the required measurement time, thereby substantially increasing clinical applicability.

  4. Automatic fuzzy contouring and parameter extraction of the left ventricle from multi-slice MR images

    Cardiac MR Imaging is a non invasive technique that allows the acquisition of a series of short-axis slices of the heart. These images encompass the entire left ventricle in the different phases of the cardiac cycle. The principal physiological parameters extracted from this series are the ejection fraction and the wall thickness. To this end, the determination of both the endocardial and the epicardial contour is required. Following the extraction of three parameters for each pixel, the fuzzy set of the cardiac contour points is defined. The first parameter depends on the pixel grey level value, the second on the presence of an edge and the third on the information retrieved on the previous slice. The calculation of the membership degree to the fuzzy set of the cardiac contour points for each pixel involves the creation of a matrix of membership degrees. The cardiac contours are determined on this matrix with the aid of a dynamic programming technique, graph searching. (authors)

  5. Assessment of colonic disease by multi-slice CT pneumocolon after incomplete colonoscopy

    Objective: To evaluate the use of preoperative MSCT in patients with clinically suspected colorectal disease after incomplete colonoscopy. Methods: After incomplete colonoscopy, 31 patients underwent MSCT before and after intravenous injection of iodinated contrast agent. CT virtual colonography (CTVC), multiplanar reformation (MPR), shaded surface display (SSD), and Raysum images were obtained by using 4 different software in workstation. The results of MSCT were compared with the findings of colonoscopy, intraoperative colon palpation, and postoperative pathology. Results: After incomplete colonoscopy, MSCT was successfully performed in all 31 cases. Postoperative pathology revealed 22 colorectal cancers (one synchronous cancers, two with polyps) and 9 benign disease. 22 colonic carcinomas were all correctly diagnosed by MSCT (including synchronous disease), 2 benign diseases were misdiagnosed as malignancy, and one polyp was missed. Conclusion: MSCT is a feasible and useful method for evaluating the entire colon before surgery in patients with occlusive disease. (author)

  6. Study of adult nasal airway by multi-slice spiral CT

    Objective: To investigate the characteristics and value of nasal area-distance curves. Methods: Based on data from CT images, nasal cavity cross-sectional areas in 60 volunteers were reconstructed. The size of each nasal airway and the distance from nostril to the corresponding cross-sectional area were measured. Area-distance curves were then established according to data obtained. t test was used to analysis the data. Results: Three types of curves were found and categorized according to their shapes. Type Ⅰ consisted of 56 sides (46.7%), type Ⅱ 40 sides (33.3%), and type Ⅲ 24 sides (20.0%). For curves of nasal valve area, smooth type was seen in 86 sides (71.7%), and concave type in 34 sides (28.3%). Curves in area of inferior turbinate head were seen with shallow notch (48 sides, 40.0%), deep notch (54 sides, 45.0%), and no notch(18 sides, 15.0%). Curves in area of middle turbinate head were seen with shallow notch (31 sides, 25.8%), deep notch (38 sides, 31.7%), and no notch (51 sides, 42.5%). Nasal minimal cross-sectional area was located at nasal valve area in 76 sides (63.3%), head of inferior turbinate in 26 sides (21.7%), region anterior to nasal valve in 15 sides (12.5%), head of middle turbinate in 1 side, and region anterior to choana in 2 sides. The cross-sectional area at nasal valve m men and women were (197.9±41.2) and (151.2±35.5) mm2, respectively. The cross-sectional area at choana in men and women were (361.8±97.9) and (296.3 81.8) mm2, respectively. There was significant difference between men and women at both sites (t=4.707 and 0.007, P<0.01). The distance from nostril to nasal valve in men and women were (14.0±2.4) and (11.8±2.9) mm, which presented significant difference, too (t=3.232, P<0.01). Conclusions: CT nasal area-distance curve varied with individual, CT may provide information for evaluating nasal passage on individual basis. (authors)

  7. The clinical research of multi-slice spiral CT in intestinal imaging

    Objective: To investigate the value and usefulness of optimized multislice CT enterography (MSCTE) with orally administered isosmotic mannitol (2.5%) as negative contrast in demonstrating the small bowel and its abnormality. Methods: Forty patients suspected of intestinal tumors were randomly divided into two groups and underwent conventional or optimized MSCTE. The expansion degree of bowel lumen and the thickness of bowel wall were evaluated for the six segments of the small intestine. The other 20 patients suspected of gastrointestinal diseases underwent gastrointestinal CT imaging, The expansion degree of bowel lumen and the wall thickness of bowel wall were statistically analyzed with Chi-Square test and t test. Results: The wall thickness of the stomach, ileum and colon were (2.56± 0.52), (1.41±0.15), (1.46±0.13), (1.91±0.25), (1.97±0.26), (2.01±0.19), (2.04±0.24) and (2.05±0.18)mm. Optimized method was superior to conventional method in the expansion degree of the second and third segments of the small intestine (P0.05). The gastrointestinal CT imaging was poor in the depiction of' the duodenum and jejunum, but stomach, ileum and colon were fully illustrated. Conclusion: Optimized MSCTE was superior to conventional method in demonstrating the small bowel, and gastrointestinal CT imaging can expand diagnostic scope because of good observation of whole gastrointestinal tract. (authors)

  8. Recurrent Fully Convolutional Neural Networks for Multi-slice MRI Cardiac Segmentation

    Poudel, Rudra P K; Lamata, Pablo; Montana, Giovanni

    2016-01-01

    In cardiac magnetic resonance imaging, fully-automatic segmentation of the heart enables precise structural and functional measurements to be taken, e.g. from short-axis MR images of the left-ventricle. In this work we propose a recurrent fully-convolutional network (RFCN) that learns image representations from the full stack of 2D slices and has the ability to leverage inter-slice spatial dependences through internal memory units. RFCN combines anatomical detection and segmentation into a si...

  9. Multi-slice spiral CT evaluation in Crohn's disease of small bowel

    Objective: To assess the value of enhanced MSCT scan for the Crohn's disease of small bowel. Methods: Fourty-five patients of small bowel Crohn's disease who were proved by multi-method were examined by two-phase enhanced scan with MSCT. The images were reformed in ADW 4.2 by MPR mainly. The CT values of the lesion segments in different phases were tested, with one way ANOVA in statistical analysis; the density difference between the lesion segments and normal segments in different phases were tested, the cases were divided according to 10 HU, and compared them with each other by χ2 test. Results: The average CT value of lesion segments was (39.3±3.7) HU in plain scan, (74.8±13.8) HU in artery phase, (90.2±12.3) HU in portal vein phase, there were sinigicant difference in them (F=258.87, P10 HU respectively in plain scan, 6 cases and 39 cases in artery phase, 2 cases and 43 cases in portal vein phase, by χ2 test, there were sinigicant difference between plain scan and artery phase (χ2=32.49, P2= 39.22, P2= 1.10, P>0.05). After enhancement, the lesions can display clearly than plain scan, and the detectable rate was raised highly. Conclusion: Two-phase enhancement scan can diagnosis the Crohn's disease of small bowel and evaluate it overall. (authors)

  10. Functional Study of the Heart using MRI and Multi-slice CT (MSCT

    "Sh. Akhlaghpour

    2005-08-01

    Full Text Available Introduction & Background: By using newer imaging techniques (MRI and MSCT, it is possible to perform functional studies of the heart including, wall mo-tion, chamber volume evaluation, and myocardial mass and wall thickness. While MRI had recently been introduced as the gold standard method for the morphological and functional studies of the heart, recent advances in the number of detectors, rotation time, and reconstruction protocols made Multislice CT (MSCT another new application for functional studies of the heart too. Ordinary raw data for coro-nary CT angiography is sufficient for these functional studies. Apart from the point that which technique is to be used to get a standard and reproducible meas-urement, a proper imaging strategy is necessary. To use MSCT, various softwares are available for these studies. By the use of these two modalities, valvular evaluations are also possible as addressed in many recent publications. In this article the strategy for functional study of the heart is presented and some case studies are also discussed.

  11. Micro computed tomography features of laryngeal fractures in a case of fatal manual strangulation.

    Fais, Paolo; Giraudo, Chiara; Viero, Alessia; Miotto, Diego; Bortolotti, Federica; Tagliaro, Franco; Montisci, Massimo; Cecchetto, Giovanni

    2016-01-01

    Cases of subtle fatal neck compression are often complicated by the lack of specificity of the post-mortem signs of asphyxia and by the lack of clear signs of neck compression. Herein we present a forensic case of a 45-year-old schizophrenic patient found on the floor of the bedroom of a psychiatric ward in cardiopulmonary arrest and who died after two days in a vegetative state. The deposition of the roommate of the deceased, who claimed responsibility for the killing of the victim by neck compression, was considered unreliable by the prosecutor. Autopsy, toxicological analyses, and multi-slice computed tomography (MSCT), micro computed tomography (micro-CT) and histology of the larynx complex were performed. Particularly, micro-CT analysis of the thyroid cartilage revealed the bilateral presence of ossified triticeous cartilages and the complete fragmentation of the right superior horn of the thyroid, but it additionally demonstrated a fracture on the contralateral superior horns, which was not clearly diagnosable at MSCT. On the basis of the evidence of intracartilaginous laryngeal hemorrhages and bilateral microfracture at the base of the superior horns of the larynx, the death was classified as a case of asphyxia due to manual strangulation. Micro-CT was confirmed as a useful tool in cases of subtle fatal neck compression, for the detection of minute laryngeal cartilage fractures, especially in complex cases with equivocal findings on MSCT. PMID:26832384

  12. Flat panel computed tomography of human ex vivo heart and bone specimens: initial experience

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

    2005-02-01

    The aim of this technical investigation was the detailed description of a prototype flat panel detector computed tomography system (FPCT) and its initial evaluation in an ex vivo setting. The prototype FPCT scanner consists of a conventional radiographic flat panel detector, mounted on a multi-slice CT scanner gantry. Explanted human ex vivo heart and foot specimens were examined. Images were reformatted with various reconstruction algorithms and were evaluated for high-resolution anatomic information. For comparison purposes, the ex vivo specimens were also scanned with a conventional 16-detector-row CT scanner (Sensation 16, Siemens Medical Solutions, Forchheim, Germany). With the FPCT prototype used, a 1,024 x 768 resolution matrix can be obtained, resulting in an isotropic voxel size of 0.25 x 0.25 x 0.25 mm at the iso-center. Due to the high spatial resolution, very small structures such as trabecular bone or third-degree, distal branches of coronary arteries could be visualized. This first evaluation showed that flat panel detector systems can be used in a cone-beam computed tomography scanner and that very high spatial resolutions can be achieved. However, there are limitations for in vivo use due to constraints in low contrast resolution and slow scan speed. (orig.)

  13. Impact of iterative reconstruction on shape reproducibility of three-dimensional computed tomography

    The purpose of this study was to evaluate the effect of an iterative reconstruction method (IR) on shape reproducibility in three-dimensional (3D) computed tomography images. We used an IR (sinogram-affirmed iterative reconstruction: SAFIRE) implemented in a 64-channel multi slice computed tomography system (Siemens, SOMATOM Definition AS). We scanned a simulated vessel phantom with 180-Hounsfield unit (HU) vessel contrast at various radiation doses and reconstructed axial images of filtered back projection (FBP) and SAFIRE. Then we reconstructed multi-planar reconstruction (MPR) and volume rendering (VR) images from the axial images. Roundness was evaluated from MPR images and vessel surface roughness was evaluated from pixel value profiles of a vessel in VR images and visual evaluation by radiological technologists. In comparison on equivalent dose, the roundness and roughness were improved with increase of SAFIRE strength level. However, in comparison on equivalent noise (standard deviation: SD) of axial images, SAFIRE strength levels of 2 to 5 were significantly inferior to FBP (p<0.05). SAFIRE strength of 1 with a dose reduction of 19% maintained the shape reproducibility in all evaluations. Therefore, it would be not appropriate to use the SD of axial image as index for the dose reduction rate determination of 3D-CT images. (author)

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

    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.)

  15. Prone position is essential for detection of pulmonary vein pseudostenosis by enhanced multidetector computed tomography in patients who undergo pulmonary vein isolation

    Pulmonary vein (PV) stenosis is a major complication of PV isolation (PVI) by catheter ablation, so in the present study the optimal position for detecting PV stenosis on enhanced multidetector computed tomography (MDCT) image acquisition was determined. The 64-slice enhanced MDCT was carried out before and after PVI in 116 consecutive patients with atrial fibrillation while they were in the prone position, as well as while supine. The supine position MDCT image showed >50% diameter stenosis of the PV in 11 (9%) patients before PVI (% diameter stenosis: mean 55±4%, range 51-65%). Greater than 50% diameter stenosis was seen in the left inferior PV in all 11 patients. The prone position attenuated the PV stenosis findings in the MDCT images in all 11 patients (mean 9±6%, range 2-18%). Stenosis visualized on images acquired in the supine position was, therefore, concluded to be pseudostenosis caused by descending aorta compression. At 3 months after PVI, no significant changes in PV diameter were observed in these 11 patients. The present study demonstrated that the prone position is essential for eliminating PV pseudostenosis observed on supine-position enhanced MDCT images. The results also indicate that preexisting PV organic stenosis is rare. (author)

  16. Sex-specific biatrial volumetric measurements obtained with use of multidetector computed tomography in subjects with and without coronary artery disease.

    Budoff, Matthew J; Pagali, Sandeep R; Hamirani, Yasmin S; Chen, Andy; Cheu, Gordon; Gao, Yanlin; Li, Dong; Mao, SongShou

    2014-06-01

    Atrial volumetric measurement has proven clinical implications. Advances in cardiac imaging, notably the precision enabled by multidetector computed tomography (MDCT), herald the need for new criteria of what constitutes normal volumetric measurements. With use of 64-slice MDCT, we compared the atrial volumes in healthy individuals with those in individuals with coronary artery disease. By means of manual segmentation, we measured biatrial volume in 686 participants who underwent retrospective electrocardiographic-gated MDCT angiographic evaluation. The study population included a control group of 203 persons with no cardiac abnormalities, and a study group of 483 patients with obstructive coronary artery disease. All variables were compared between men and women and between the groups. We found a significant difference in left atrial end-systolic and end-diastolic volumes between men and women in the control group (P <0.05); however, right atrial volumes were similar. In comparison with the entire control group, the coronary artery disease group had significantly higher left atrial volume, significantly lower right atrial stroke volume, and significantly lower biatrial ejection fraction, except for left atrial ejection fraction in men. Right atrial volume and left atrial stroke volume were not significantly different. The results imply that a sex-specific reference value is necessary for left atrial volumetric evaluation, and that left atrial volume and biatrial ejection fraction (excluding left atrial ejection fraction in men) might be useful during diagnosis and prognosis in patients who have coronary artery disease. PMID:24955043

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

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

    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.)

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

    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

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

    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

  20. The prevalence of coronary artery variations on coronary computed tomography angiography

    Background: Coronary computed tomography angiography (CCTA) can delineate the coronary artery anatomy precisely. Basic knowledge of the normal coronary artery anatomy and familiarity with its common variations are essential in order to assess CCTA accurately. Purpose: To determine the prevalence of coronary artery variations detected by 64-slice multidetector CT. Material and Methods: CCTA images of 2096 patients were evaluated retrospectively. Relatively unusual coronary artery morphological features that were seen in greater than 1% of the study population were classified as variations. Results: Coronary artery circulation was right dominant in 86.6%, left dominant in 9.6%, and balanced in 3.8% of patients. The conus artery arose from the right coronary artery in 83%, or directly from the aorta with a separate ostium in 17% of cases which was much more common in men than women. The sinoatrial node artery originated from the right coronary artery (65.6%) or the circumflex artery (33.7%). The atrioventricular node artery originated from the right coronary artery in 86.4% or the circumflex artery in 13.6% of cases. The left main coronary artery was shorter than 0.5 cm in 4.7% of cases and trifurcated into the intermediate artery in 31.3% of cases. A myocardial bridge was observed in 21.6%, coronary ectasia-aneurysm in 2%, dual left anterior descending artery (LAD) type 1 in 1.38%, and a variant of type 1 in 0.1% of cases. The presence of coronary atherosclerosis was higher in patients with coronary ectasia-aneurysm than the patients who did not have coronary ectasia-aneurysm (90.5% vs. 72.2%, P = 0.000). Conclusion: CCTA is a non-invasive imaging modality for the depiction of variations of the coronary arteries. The incidence of coronary artery variations is high and various, and readers should be familiar and looking for these conditions during interpretation of CCTA examinations

  1. Determination of computed tomography diagnostic reference levels in North-Central Nigeria

    The aim of this study is to estimate computed tomography (CT) dose levels for common CT examinations in North-Central Nigeria. Dose parameters and scan parameters for the most commonly performed CT examinations (head, chest and abdominal CT scans) were surveyed during a four month period in 4 CT centres with Multislice scanning capabilities (4- 64 slices). Data on CT volume index (CTDIvol) and dose length product (DLP) displayed on scanner console was recorded for a minimum of 10 averaged-sized (70±10kg) patients for each facility to estimate the DRLs. The rounded 75th percentile of the distribution was then used to calculate a DRL for each centre and the region by compiling all results from centres surveyed. Data for 226 patients was collected. CT dosimetry software Impact CT patient dosimetry calculator, version 1.0.4 with National Radiation Protection Board SR250 data set was used to validate and compare surveyed scanner generated dose values. Estimated regional DRLs for head, chest and abdominal scans are (60mG and 1024 mGy.cm), (10mGy and 407mGy.cm) and (15mGy and 757mGy.cm) for CTDIvol and DLP respectively. Mean effective dose values are 1.7mSv, 5mSv and 11.9mSv for head, chest and abdominal scan respectively. A wide variation of mean doses was observed across the centres, however, DRLs estimates were lower than EC (1999) values but above UK (2003) DRLs except for chest examination, this indicates a need for optimization. Validation result show unity (‹10% overall variation) between scanner generated and software calculated dose values. (au)

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

    Martin J Willemink

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

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

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

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

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

    2010-07-15

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

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

    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.

  6. Utilizing computed tomography scans for analysis of motorcycle helmets in real-world crashes - biomed 2011.

    Loftis, Kathryn L; Moreno, Daniel P; Tan, Joshua; Gabler, Hampton C; Stitzel, Joel D

    2011-01-01

    In 2008, there were more than 5,000 motorcycle crash fatalities in the United States. Many states have motorcycle helmet laws that are meant to protect riders during a crash. After recruiting motorcycle occupants injured in crashes, a protocol was established to scan three different types of motorcycle helmets commonly worn (cap, ¾ shield, and full face shield) using a computed tomography (CT) scanner. The protocol developed was for a GE 64 slice PET/CT Discovery VCT scanner with axial images from anterior to posterior helmet acquired in helical mode. It had 512x512 resolution and the full face and ¾ face shield helmets were scanned with greater voxels in the axial plane compared to the skull cap helmets. New helmets were scanned as exemplary images for comparison with helmets involved in motorcycle crashes. After CT scans were gathered, three-dimensional reconstructions were made to visualize scratches and impacts to the exterior of the helmets. Initial work was also conducted in analyzing interior components, and a trend was seen in decreased thickness between the interior foam and shell with sides of the exterior helmet thought to have contacted roadside barriers or the ground during motorcycle crashes. These helmet analysis methods have been established, and will be used to investigate multiple motorcycle crashes in conjunction with occupant injuries and direct head impacts to improve helmet design and the understanding of head injuries. This work also establishes the basis for development of finite element models of three of the most common helmet types. PMID:21525626

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

    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)

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

    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

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

    Brunner, Stephen T.

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

  10. The Noninvasive Diagnosis and Postoperative Evaluation of Anomalous Right Coronary Artery from the Pulmonary Artery (ARCAPA) using Coronary MDCT: A Case Report

    Lim, Jae Hoon; Seon, Hyun Ju; Kim, Yun Hyeon [Chonnam National University Hospital, Gwangju (Korea, Republic of); Choi, Song; Kang, Yang Jun [Chonnam National University Hwasun Hospital, Hwasun (Korea, Republic of)

    2010-02-15

    A 63-year-old man was admitted with complaints of exertional dyspnea and atypical chest pain. Coronary angiography and 64-slice multidetector computed tomography (MDCT) revealed an anomalous origin of the right coronary artery from the pulmonary artery (ARCAPA). He received a coronary artery bypass graft (CABG). The incidence of ARCAPA is extremely rare. We report here on the first case of ARCAPA that was noninvasively diagnosed and postoperatively followed up with 64-slice MDCT.

  11. Review: Pre- and postinterventional control of stent grafts by means of single and multislice spiral computerized tomography

    Purpose. Could contrast enhanced computed tomography replace conventional catheter angiography in the preoperative evaluation of aortic aneurysms before stentgraft implantation? Does multi slice computed tomography have advantages comparing to single slice computed tomography? Methods. We compared 15 single slice with 13 multi slice computed tomography studies and reconstructions according to their ability to replace conventional catheter angiography in the preoperative evaluation. In the postoperative follow-up 60 single slice computed tomography studies were compared to 60 multi slice studies. Results. By using appropriate reconstructions the spiral computed tomography studies could deliver all information necessary for implantation. In our study no advantage of multi slice computed tomography could be detected. In the postoperative evaluation of stengrafts our computed tomography scan protocol could detect all relevant complications in single and multi slice computed tomography. No significant advantage of multi slice computed tomography could be detected. Conclusion. Contrast enhanced computed tomography is equal to conventional catheter angiography in the pre- and postoperative evaluation of stentgrafts. No significant advantage of multi slice versus single slice could be detected. (orig.)

  12. Evaluation by multislice computed tomography of atherosclerotic coronary artery plaques in non-culprit, remote coronary arteries of patients with acute coronary syndrome

    Patients with acute coronary syndrome (ACS) frequently have vulnerable plaques in the remote coronary arteries, suggesting that ACS is part of the pan-coronary process. In the present study the computed tomography (CT) plaque density in non-culprit atherosclerotic coronary artery lesions was evaluated by multi-slice computed tomography (MSCT) in patients with ACS and non-ACS. MSCT was performed in 21 patients with ACS and 53 patients with non-ACS: 16 of the 21 ACS patients (76%) and 30 of the non-ACS 53 patients (57%) had non-calcified plaques in the non-culprit coronary arteries (p=0.18). CT-low-density plaques (CT density <68 Hounsfield units (HU)) were more frequent in the ACS group (13/16 patients, 81%) than in the non-ACS group (13/30 patients, 43%, p=0.03). In addition, the CT density of the non-culprit lesion was significantly lower in patients with ACS than in those with non-ACS (44.1±22.9 and 77.3±33.7 HU, respectively). Patients with ACS more frequently had CT-low-density plaques in the non-culprit, remote arteries than those with non-ACS, which suggests that ACS treatment should focus not only on stabilizing the culprit lesion but also on systemic stabilization of non-culprit lesions. (author)

  13. Reference absolute and indexed values for left and right ventricular volume, function and mass from cardiac computed tomography

    Left ventricular (LV) and right ventricular (RV) volumetric and functional parameters are important biomarkers for morbidity and mortality in patients with heart failure. To retrospectively determine reference mean values of LV and RV volume, function and mass normalised by age, gender and body surface area (BSA) from retrospectively electrocardiographically gated 64-slice cardiac computed tomography (CCT) by using automated analysis software in healthy adults. The study was approved by the institutional review board with a waiver of informed consent. Seventy-four healthy subjects (49% female, mean age 49.6±11) free of hypertension and hypercholesterolaemia with a normal CCT formed the study population. Analyses of LV and RV volume (end-diastolic, end-systolic and stroke volumes), function (ejection fraction), LV mass and inter-rater reproducibility were performed with commercially available analysis software capable of automated contour detection. General linear model analysis was performed to assess statistical significance by age group after adjustment for gender and BSA. Bland–Altman analysis assessed the inter-rater agreement. The reference range for LV and RV volume, function, and LV mass was normalised to age, gender and BSA. Statistically significant differences were noted between genders in both LV mass and RV volume (P-value<0.0001). Age, in concert with gender, was associated with significant differences in RV end-diastolic volume and LV ejection fraction (P-values 0.027 and 0.03). Bland–Altman analysis showed acceptable limits of agreement (±1.5% for ejection fraction) without systematic error. LV and RV volume, function and mass normalised to age, gender and BSA can be reported from CCT datasets, providing additional information important for patient management.

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

    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.

  15. Clinical application of low-dose CT combined with computer-aided detection in lung cancer screening

    Objective: To investigate the clinical value of chest low-dose CT (LDCT) combined with computer-aided detection (CAD) system for lung cancer screening in high risk population. Methods: Two hundred and nineteen healthy candidates underwent 64-slice LDCT scan. All images were reviewed in consensus by two radiologists with 15 years of thoracic CT diagnosis experience. Then the image data were analyzed with CAD alone. Finally images were reviewed by two radiologists with 5 years of CT diagnosis experience with and without CT Viewer software. The sensitivity, false positive rate of CAD for pulmonary nodule detection were calculated. SPSS 11.5 software and Chi-square test were used for the statistics. Results: Of 219 candidates ,104(47.5% ) were detected with lung nodules. There were 366 true nodules confirmed by the senior radiologists. The CAD system detected 271 (74.0%) true nodules and 424 false-positive nodules. The false-positive rate was 1.94/per case. The two junior radiologists indentifid 292 (79.8%), 286(78.1%) nodules without CAD and 336 (91.8%), 333 (91.0%) nodules with CAD respectively. There were significant differences for radiologists in indentifying nodules with or without CAD system (P<0.01). Conclusions: CAD is more sensitive than radiologists for indentifying the nodules in the central area or in the hilar region of the lung. While radiologists are more sensitive for the peripheral and sub-pleural nodules,or ground glass opacity nodules, or nodules smaller than 4 mm. CAD can not be used alone. The detection rate can be improved with the combination of radiologist and CAD in LDCT screen. (authors)

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

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

    2011-06-01

    Computed tomography (CT) was used for preoperative planning of minimal-invasive total hip arthroplasty (THA). 92 patients (50 males, 42 females, mean age 59.5 years) with a mean body-mass-index (BMI) of 26.5 kg/m(2) underwent 64-slice CT to depict the pelvis, the knee and the ankle in three independent acquisitions using combined x-, y-, and z-axis tube current modulation. Arthroplasty planning was performed using 3D-Hip Plan(®) (Symbios, Switzerland) and patient radiation dose exposure was determined. The effects of BMI, gender, and contralateral THA on the effective dose were evaluated by an analysis-of-variance. A process-cost-analysis from the hospital perspective was done. All CT examinations were of sufficient image quality for 3D-THA planning. A mean effective dose of 4.0 mSv (SD 0.9 mSv) modeled by the BMI (p<0.0001) was calculated. The presence of a contralateral THA (9/92 patients; p=0.15) and the difference between males and females were not significant (p=0.08). Personnel involved were the radiologist (4 min), the surgeon (16 min), the radiographer (12 min), and administrative personnel (4 min). A CT operation time of 11 min and direct per-patient costs of 52.80 € were recorded. Preoperative CT for THA was associated with a slight and justifiable increase of radiation exposure in comparison to conventional radiographs and low per-patient costs. PMID:20022723

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

    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.

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

    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.

  19. Preliminary study on hemodynamics in human carotid bifurcation by computational fluid dynamics

    Objective: To investigate the visualization and quantitation of hemodynamic variables at carotid artery bifurcation in vivo by combining computational fluid dynamics (CFD) and vascular imaging. Methods: A healthy volunteer underwent CT angiography of left carotid artery by SIEMENS multi-slice CT. Parameters of hemodynamics at this carotid bifurcation were calculated and visualized by combining vascular imaging post-processing and CFD. Results: (1) The average range of flow velocity was 0.04-0.36 m/s. A region of high velocity was seen at medial wall of internal carotid artery (ICA) and medial wall of external carotid artery (ECA), respectively. The largest contiguous region of low velocity occurred at the carotid bulb. (2)The average range of absolute pressure, static pressure and dynamic pressure was 100 266.70-101 615.90 Pa, -1058.34-290.88 Pa, and 6.12-553.25 Pa, respectively. (3) The average range of wall shear stress (WSS) at the bifurcation was 0.59-5.35 Pa. There was a large region of low WSS at carotid bulb and posterior wall of ICA, with the lowest value of 0.25 Pa. Also there was a small region of low WSS at anterior and lateral wall of ECA. Conclusion: CFD combined with vascular imaging can calculate and visualize the parameters of hemodynamics at carotid bifurcation in vivo individually. It is an interdisciplinary science of computer, radiology and hemodynamics and provides a new method to investigate the relationship of vascular geometry and flow condition with atherosclerotic pathological changes. (authors)

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

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

    2015-04-15

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

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

    Arnous, Samer

    2012-02-01

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

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

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

    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.)

  3. Radiation doses in pediatric computed tomography procedures: Challenges facing new technologies

    Despite the fact that in recent years an increasing number of radiologists and radiological technologists have been applying radiation dose optimization techniques in paediatric Computed Tomography (CT) examinations, dual and multi-slice CT (MSCT) scanners present a new challenge in Radiation Protection (RP). While on one hand these scanners are provided with Automatic Exposure Control (AEC) devices, dose reduction modes and dose estimation software, on the other hand Quality Control (QC) tests and CT Kerma Index (C) measurements and patient dose estimation present specific difficulties and require changes or adaptations of traditional QC protocols. This implies a major challenge in most developing countries where Quality Assurance Programmes (QAP) have not been implemented yet and there is a shortage in the number of medical physicists This paper analyses clinical and technical protocols as well as patient doses in 204 CT body procedures performed in 154 children. The investigation was carried out in a paediatric reference hospital of Uruguay, where are performed an average of 450 paediatric CT examinations per month in a sole CT dual scanner. Besides, CVOL reported from the scanner display was registered in order to be related with the same dosimetric quantity derived from technical parameters and C values published on tables. Results showed that not all the radiologists applied the same protocol in similar clinical situations delivering unnecessary patient dose with no significant differences in image quality. Moreover, it was found that dose reduction modes represent a drawback in order to estimate patient dose when mA changes according to tissue attenuation, in most cases in each rotation. The study concluded on the importance of QAP that must include education on RP of radiologists and technologists, as well as in the need of medical physicists to perform QC tests and patient dose estimations and measurements. (author)

  4. Radiation doses in pediatric computed tomography procedures: challenges facing new technologies

    Despite the fact that in recent years an increasing number of radiologists and radiological technologists have been applying radiation dose optimization techniques in paediatric Computed Tomography (CT) examinations, dual and multi -slice CT (MSCT) scanners present a new challenge in Radiation Protection (RP). While on one hand these scanners are provided with Automatic Exposure Control (AEC) devices, dose reduction modes and dose estimation software, on the other hand Quality Control (QC) tests and CT Kerma Index (C) measurements and patient dose estimation present specific difficulties and require changes or adaptations of traditional QC protocols. This implies a major challenge in most developing countries where Quality Assurance Programmes (QAP) have not been implemented yet and there is a shortage in the number of medical physicists This paper analyses clinical and technical protocols as well as patient doses in 204 CT body procedures performed in 154 children. The investigation was carried out in a paediatric reference hospital of Uruguay, where are performed an average of 450 paediatric CT examinations per month in a sole CT dual scanner. Besides, CVOL reported from the scanner display was registered in order to be related with the same dosimetric quantity derived from technical parameters and C values published on tables. Results showed that not all the radiologists applied the same protocol in similar clinical situations delivering unnecessary patient dose with no significant differences in image quality. Moreover, it was found that dose reduction modes represent a drawback in order to estimate patient dose when mA changes according to tissue attenuation, in most cases in each rotation. The study concluded on the importance of QAP that must include education on RP of radiologists and technologists, as well as in the need of medical physicists to perform QC tests and patient dose estimations and measurements. (author)

  5. Predictive Modelling of Cardiac 2D Multi-Slice MRI with Simultaneous Resolution of Cardiac and Respiratory Motion

    Pedersen, Henrik; Ólafsdóttir, Hildur; Darkner, Sune;

    2009-01-01

    This paper introduces a novel approach to modelling of volumetric cardiac magnetic resonance imaging (MRI) with simultaneous resolution of cardiac and respiratory motion. The major challenge is that the inherent slow nature of MRI prevents obtaining real-time volumetric images of the heart with...... respiratory bellow and a vectorcardiogram, and utilizes a combination of deformation modelling and pixel intensity modelling. We demonstrate that this approach reliably models volumetric cardiac MRI for any combination of cardiac and respiratory phase....

  6. Predictive Modelling of Cardiac 2D Multi-Slice MRI with Simultaneous Resolution of Cardiac and Respiratory Motion

    Pedersen, Henrik; Ólafsdóttir, Hildur; Darkner, Sune; Lyksborg, Mark; Larsen, Rasmus

    2009-01-01

    This paper introduces a novel approach to modelling of volumetric cardiac magnetic resonance imaging (MRI) with simultaneous resolution of cardiac and respiratory motion. The major challenge is that the inherent slow nature of MRI prevents obtaining real-time volumetric images of the heart with sufficient spatial and temporal resolution. To overcome this problem our method predicts pixel intensities in multiple 2D slices, acquired with high spatial and temporal resolution, and subsequently as...

  7. Multi-slice echo-planar spectroscopic MR imaging provides both global and local metabolite measures in multiple sclerosis

    Mathiesen, Henrik Kahr; Tscherning, Thomas; Sorensen, Per Soelberg;

    2005-01-01

    MR spectroscopy (MRS) provides information about neuronal loss or dysfunction by measuring decreases in N-acetyl aspartate (NAA), a metabolite widely believed to be a marker of neuronal viability. In multiple sclerosis (MS), whole-brain NAA (WBNAA) has been suggested as a marker of disease...... progression and treatment efficacy in treatment trials, and the ability to measure NAA loss in specific brain regions early in the evolution of this disease may have prognostic value. Most spectroscopic studies to date have been limited to single voxels or nonlocalized measurements of WBNAA only...

  8. The value of multi-slice spiral CT liver perfusion imaging to evaluate the chronic hepatic fibrosis and cirrhosis

    Objective: To investigate the value of the MSCT liver perfusion imaging parameters in the evaluation of the chronic hepatic fibrosis and cirrhosis. Methods: Liver CT perfusion (CTP) was performed in 107 participants,including 31 patients with mild hepatic fibrosis (S1, S2), 34 patients with severe hepatic fibrosis (S3, S4) and early stage of hepatic cirrhosis which conformed by liver pathologic biopsy, 42 patients with hepatic cirrhosis who had typical clinical and image signs, and 30 healthy subjects as control group. The data of CTP (HAP, PVP, LTP, HPI and TTP) at different stages were obtained with Body perfect CT-syngo CT2007A and control study with histopathologic stage. Compared the study index by the one-way ANOVA analysis. Used Spearman rank correlation to analysis the relationship between liver perfusion imaging parameters and the degrees of the chronic hepatic fibrosis. Used Logistic regression to analysis the maximum regression coefficient among the liver perfusion imaging parameters, which affected the histopathologic stage mostly. Results: In the subgroups of the chronic hepatic fibrosis S1, S2, S3, S4 to the hepatic cirrhosis,HAP values was (28.9 ±8.6), (24.6 ±2.4), (29.2 ±2.3) and (38.9 ± 7.0) ml · 100 ml-1 · min-1, respectively. HAP decreased firstly,then increased. Statistic analysis showed the difference of HAP between later-stage cirrhosis and other groups (F=40.26, P<0.01). PVP values of above subgroups was (111.3 ± 18.1), (92.9 ±5.3), (73.0 ±9.0) and (54.1 ± 13.8) ml · 100 ml-1 ·min-1, respectively. TLP values of above subgroups was (140.2 ± 25.9), (117.1 ± 4.5), (102.3 ± 8.7)and (93.0 ± 11.8) ml · 100 ml-1·min-1, respectively. The difference of PVP, TLP among each subgroup was significant (F=136.79, 67.40, respectively, P<0.01). HPI values of above subgroups was (20.4 ± 2.6)%, (21.0 ±2.1)%, (28.5 ±3.1)% and (42.6± 11.1)%, respectively. TTP values of above subgroups was (123.7±22.2), (137.1 ±27.1), (145.0 ±28.6) and (166.5 ±25.1)s, respectively. The difference of HPI, TTP among each subgroup was significant (F=93.05, 17.37, respectively; P<0.01). PVP, TLP was significant negative correlation with the degree of the hepatic fibrosis (r=-0.920, -0.846, respectively; P<0.01). HAP, HPI and TTP was significant positive correlation with the degree of the hepatic fibrosis (r=0.611, 0.882 and 0.545, respectively; P<0.01). Logistic regression analysis showed the regression coefficient of PVP (-8.798) was maximum.With an area under the receiver operating characteristic curve of PVP =84.76 ml · 100 ml-1 · min-1 as a diagnose critical point. The sensitivity was 0.890, the specificity was 0.950, and the accuracy was 0.931 in the prediction of the chronic hepatic fibrosis. Conclusions: MSCT liver perfusion imaging parameters can reflect the hemodynamic changes of chronic hepatic fibrosis and cirrhosis. CTP may be helpful for differentiation the severe hepatic fibrosis and early stage of hepatic cirrhosis and later-stage cirrhosis. (authors)

  9. Multi-slice spiral CT in the diagnosis of congenital heart diseases associated with tracheobronchial stenosis in children

    Objective: To explore the diagnostic value of post processing techniques of MSCT for diagnosing congenital heart disease associated with tracheobronchial stenosis in children. Methods: Thirty four patients with congenital heart disease complicated by tracheobronchial stenosis were evaluated with MSCT. MPR, CPR, MinIP and VR were performed to show the tracheobronchial morphology. Findings in 43 segments of 32 cases were compared with the findings of surgical operation. Mann-Whitney test was employed to assess the significance of measurement between the post processing techniques and the operation. Results: The length of stenotic segments were variable seen at operation, with values between 4- 39 mm in trachea, 4-33 mm in main bronchi and 3-12 mm in lobe bronchi, respectively. The biggest difference between the measurement of operation and MSCT was 4 mm (3 segments). Other differences of stenotic segments were within 3 mm. Six segments exhibited mild, 16 moderate and 21 severe stenosis at surgery. By contrast, five segments exhibited mild, 17 moderate and 21 severe stenosis by MPR or CPR, 2 mild, 9 moderate and 32 severe stenosis by MinIP and 4 mild, 11 moderate and 28 sever stenosis by VR, respectively. There was no significant difference in measuring the degree of tracheobronchial stenosis between MPR or CPR, VR and the surgery (Z=-0.105, -1.479; P>0.05), while MinIP frequently overrated the degree of stenosis compared with the measurement at surgery (Z=-2.484, P=0.013). Conclusion: The integrated three dimensional reformations of MSCT scan can accurately evaluate the degree and extent of congenital heart disease associated with tracheobronchial stenosis in children and provide valuable information for clinical management. (authors)

  10. The measurement of organic radiation dose of multi-slice CT scanning by using the Chinese anthropomorphic chest phantom

    Objective: Using the Chinese anthropomorphic chest phantom to measure the absorbed dose of various tissues and organs under different noise index, and to assess the radiation dose of MSCT chest scanning with the effective dose (ED). Methods: The equivalence of the Chinese anthropomorphic chest phantom (CDP-1 C) and the adult chest on CT sectional anatomy and X-ray attenuation was demonstrated. The absorbed doses of various tissues and organs under different noise index were measured by laying thermoluminescent dosimeters (TLD) inside the phantom, and the corresponding dose-length products (DLP) were recorded. Both of them were later converted into ED and comparison was conducted to analyze the dose levels of chest CT scanning with automatic tube current modulation (ATCM) under different noise index. Student t-test was applied using SPSS 12.0 statistical software. Results: The Phantom was similar to the human body on CT sectional anatomy. The average CT value of phantom are - 788.04 HU in lung, 45.64 HU in heart, 65.84 HU in liver, 254.32 HU in spine and the deviations are 0.10%, 3.04%, 4.49% and 4.36% respectively compared to humans. The difference of average CT value of liver was statistically significant (t=-8.705, P0.05). As the noise index increased from 8.5 to 22.5, the DLP decreased from 393.57 mGy · cm to 78.75 mGy · cm and the organs dose declined. For example, the average absorbed dose decreased from 22.38 mGy to 3.66 mGy in lung. Compared to ED calculating by absorbed dose, the ED calculating by DLP was lower. The ED values of the two methods were 6.69 mSv and 8.77 mSv when the noise index was set at 8.5. Conclusions: Application of the Chinese anthropomorphic chest phantom to carry out CT dose assessment is more accurate. The noise index should be set more than 8.5 during the chest CT scanning based on ATCM technique. (authors)

  11. Beziehung zwischen primären Multi-Slice-CT-Befunden und posttraumatischer Lebensqualität bei polytraumatisierten Patienten

    Knopke, Steffen

    2010-01-01

    Purpose: To determine the added diagnostic benefit of using MS-CT and to determine the quality of life in multiple trauma patients differentiated by severity of injury and affected body region. Materials and Methods: A retrospective analysis was performed of the 16-row whole-body spiral CT findings in 275 multiple trauma patients (73.1% men, 26.9% women; age 39.6 ± 18.9 years) with regard to additional findings and new findings obtained with CT compared to the findings obtained by conventi...

  12. Cloud Computing Vs. Grid Computing

    Seyyed Mohsen Hashemi; Amid Khatibi Bardsiri

    2012-01-01

    Cloud computing emerges as one of the hottest topic in field of information technology. Cloud computing is based on several other computing research areas such as HPC, virtualization, utility computing and grid computing. In order to make clear the essential of cloud computing, we propose the characteristics of this area which make cloud computing being cloud computing and distinguish it from other research areas. The service oriented, loose coupling, strong fault tolerant, business model and...

  13. Should computed tomography angiography supersede invasive coronary angiography for the evaluation of graft patency following coronary artery bypass graft surgery?

    Gabriel, Joseph; Klimach, Stefan; Lang, Peter; Hildick-Smith, David

    2015-08-01

    Invasive coronary angiography (ICA) has long been the established gold standard in assessing graft patency following coronary artery bypass graft (CABG). Over the past decade or so however, improvements in computed tomography angiography (CTA) technology have allowed its emergence as a useful clinical tool in graft assessment. The recent introduction of 64-slice and now 128-slice scanners into widespread distribution, and the development of 320-detector row technology allowing volumetric imaging of the entire heart at single points in time within one cardiac cycle, has increased the potential of CTA to supersede ICA in this capacity. This study sought to examine the evidence surrounding this potential. A best evidence topic was constructed according to a structured protocol. The enquiry: In [patients who have undergone coronary artery bypass graft surgery] is [computed tomography angiography or invasive coronary angiography] superior in terms of [graft patency assessment, stenosis detection, radiation exposure and complication rate]? Four hundred and twenty-four articles were identified from the search strategy. Four additional articles were identified from references of key articles. Seventeen articles selected as best evidence were tabulated. The reliability of CTA as a tool in the detection of graft patency and stenosis has continued to improve with each successive generation of multislice technology. The latest 64- and 128-slice CTA techniques are able to detect graft patency and stenosis with very high sensitivities and specificities comparable with ICA, while remaining non-invasive procedures associated with fewer complications (ICA carries a 0.08% risk of myocardial infarction and 0.7% risk of minor complications in clinically stable patients). Present limitations of the technology include the accurate visualization of distal anastomoses and clip artefacts. In addition, the capacity of diagnostic ICA to be combined simultaneously with percutaneous coronary

  14. Computer-aided detection of nodule in low-dose CT screening for lung cancer

    Objective: To evaluate the performance of computer-aided detection (CAD) system for detection of pulmonary nodules in 64-slice low-dose CT screening and to investigate whether CAD can improve the performance of radiologists in detecting pulmonary nodules. Methods: One hundred low-dose screening CT examinations were randomly selected from the database containing 578 consecutive cases between Jun 2007 and Jun 2008. All the examinations were performed on a 64-MSCT scanner with the exposure of 120 kVp, 30 or 40 mA, or automatic exposure control. Before the study started, the screening reports had been made with double reading by two radiologists. All the selected images were analyzed with the lung VCAR software from GE Healthcare with a nodule diameter threshold 3.0 mm. All discrepancies between the screening reports and the CAD results were reviewed and the true non-calcified nodules were determined in consensus by two experienced chest radiologists. Detected nodules were classified by density, size and location.The performance of the double reading and the CAD system were compared and analyzed statistically. McNemar-Bowker test was used for the statistical analysis. Results: A total of 257 true noncalcified nodules were determined in all 100 low-dose screening CT examinations. The detection rate of CAD system was 91.1% (234/257), with the missed rate of 8.9% (23/257). Twenty three nodules were missed by CAD, in which 10 were solid with the diameter ranged from 2.4 to 6.0 mm, and 13 were nonsolid with the diameter ranged from 2.1 to 8.6 mm.Of the 23 nodules, 17 were located in the outer zones of lungs and 6 in the inner zones. The double reading showed a detection rate of 59.1% (152/257) and a missed rate of 40.9% (105/257), which was significantly lower than CAD. The diameter of all the 105 missed nodules by radiologists were ranged from 2.4 to 11.8 mm, in which 94 nodules were solid, 10 were partly solid and 1 was nonsolid, with 69 located in outer zones of lungs

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

    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

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

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

    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.

  17. Development of the voxel computational phantoms of pediatric patients and their application to organ dose assessment

    Lee, Choonik

    A series of realistic voxel computational phantoms of pediatric patients were developed and then used for the radiation risk assessment for various exposure scenarios. The high-resolution computed tomographic images of live patients were utilized for the development of the five voxel phantoms of pediatric patients, 9-month male, 4-year female, 8-year female, 11-year male, and 14-year male. The phantoms were first developed as head and torso phantoms and then extended into whole body phantoms by utilizing computed tomographic images of a healthy adult volunteer. The whole body phantom series was modified to have the same anthropometrics with the most recent reference data reported by the international commission on radiological protection. The phantoms, named as the University of Florida series B, are the first complete set of the pediatric voxel phantoms having reference organ masses and total heights. As part of the dosimetry study, the investigation on skeletal tissue dosimetry methods was performed for better understanding of the radiation dose to the active bone marrow and bone endosteum. All of the currently available methodologies were inter-compared and benchmarked with the paired-image radiation transport model. The dosimetric characteristics of the phantoms were investigated by using Monte Carlo simulation of the broad parallel beams of external phantom in anterior-posterior, posterior-anterior, left lateral, right lateral, rotational, and isotropic angles. Organ dose conversion coefficients were calculated for extensive photon energies and compared with the conventional stylized pediatric phantoms of Oak Ridge National Laboratory. The multi-slice helical computed tomography exams were simulated using Monte Carlo simulation code for various exams protocols, head, chest, abdomen, pelvis, and chest-abdomen-pelvis studies. Results have found realistic estimates of the effective doses for frequently used protocols in pediatric radiology. The results were very

  18. Rethinking Computations

    Wiedermann, Jiří; van Leeuwen, J.

    Exeter: AISB, 2013 - (Bishop, M.; Erden, Y.), s. 6-10 ISBN 978-1-908187-31-4. [AISB Symposium on Computing and Philosophy: The Scandal of Computation - What is Computation? /6./. Exeter (GB), 03.04.2013-05.04.2013] R&D Projects: GA ČR GAP202/10/1333 Institutional support: RVO:67985807 Keywords : computation * epistemology * philosophy of computing Subject RIV: IN - Informatics, Computer Science

  19. Cloud Computing

    Bhavana Gupta

    2012-01-01

    Cloud computing is such a type of computing environment, where business owners outsource their computing needs including application software services to a third party and when they need to use the computing power or employees need to use the application resources like database, emails etc., they access the resources via Internet. Cloud computing the use of computing resources (hardware and software) that are delivered as a service over a (typically the Internet).

  20. Computer Music

    Cook, Perry R.

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

  1. Computer Music

    Cook, Perry

    This chapter covers algorithms, technologies, computer languages, and systems for computer music. Computer music involves the application of computers and other digital/electronic technologies to music composition, performance, theory, history, and perception. The field combines digital signal processing, computational algorithms, computer languages, hardware and software systems, acoustics, psychoacoustics (low-level perception of sounds from the raw acoustic signal), and music cognition (higher-level perception of musical style, form, emotion, etc.). Although most people would think that analog synthesizers and electronic music substantially predate the use of computers in music, many experiments and complete computer music systems were being constructed and used as early as the 1950s.

  2. Comparative study of 64-slice CT angiography and digital subtraction angiography in spontaneous subarachnoid hemorrhage cases%自发性蛛网膜下腔出血的CTA与DSA对比研究

    薛波; 高国波; 李勇; 张立军; 李昌晓

    2013-01-01

    目的:探讨64层CTA与DSA对自发性蛛网膜下腔出血(spontaneous subarachnoid hemorrhage,s-SAH)的应用价值及其限度.方法:收集153例s-SAH患者的CTA及DSA检查资料,回顾性分析2种检查方法的图像质量(采取1~3分评分制),并比较2种方法在脑动脉瘤检出方面的灵敏度、特异度及准确度.结果:图像质量评分CTA为(2.63±0.262)分,DSA为(2.73±0.254)分,二者差异无统计学意义(P>0.05).CTA对脑动脉瘤的检出的灵敏度为96.2%,特异度为94.9%,准确度为95.9%;DSA灵敏度为97.7%,特异度为97.4%,准确度为97.6%,二者差异无统计学意义(P>0.05).结论:在s-SAH患者中,CTA与DSA均能准确检出动脉瘤所致破裂出血.相较于DSA,CTA能多方位显示病变,对血管壁及血管周围情况的显示更具价值.

  3. 64层螺旋CT血管造影在蛛网膜下腔出血诊断的临床运用%Clinical application of 64-slices spiral CT angiography in diagnosing subarachnoid haemorrhage

    苏海; 孙晓川; 朱继; 唐文渊

    2007-01-01

    目的:探讨64层螺旋CT血管造影(CTA)在蛛网膜下腔出血(SAH)病因诊断中的作用.方法:对2005年9月到2006年9月收治入院的89例SAH患者行64层螺旋CT血管造影检查,其中49例同时接受数字减影血管造影(DSA)检查.分析CTA检查结果并与DSA检查结果比较.结果:89例患者中CTA检出动脉瘤70例,动静脉畸形9例,静脉窦血栓2例,阴性8例;在同时接受DSA检查的49例患者中,发现动脉瘤41例,动静脉畸形4例,阴性4例,其中除1例CTA发现并经临床证实的动脉瘤DSA检查为阴性外,其余全部证实CTA诊断.CTA对SAH病因诊断中的敏感性和特异性都为100%,DSA分别为98%和100%.结论:64层螺旋CTA对SAH的病因诊断是一种无创、快速、便捷的影像学检查方法,可显示血管的空间立体结构及周边关系,有助于治疗方法的选择和难度的评估.

  4. The value in detection of acute nontraumatic subarachnoid hemorrhage with 64 slice multidetector CT angiography%64层CTA对急性非外伤性蛛网膜下腔出血的应用价值

    杜忆兵; 闫宇涛; 王晓辉; 陆利霞

    2009-01-01

    目的:用64层螺旋CTA评价急性非外伤性蛛网膜下腔出血(SAH)病因并选择治疗方法.方法:对68例急性非外伤性SAH患者发病7天内行CTA检查,明确病因,根据CTA结果选择治疗方法并评价疗效.图像处理采用MPVR、MIP及3DVR重建.结果:68例SAH患者均经DSA及外科手术证实.其中45例为动脉瘤破裂所致,1例血管炎,2例动脉硬化,1例夹层动脉瘤,19例动脉无明显异常.68例SAH中64例由CTA做出病因诊断(准确率94.1%、敏感性91.8%、特异性100%、阳性预测值100%、阴性预测值82.6%).CTA直接显示43例动脉瘤,1例血管炎及1例夹层动脉瘤.43例动脉瘤有42例根据CTA结果选择治疗(97.7%).其中栓塞29例,有26例(89.7%)栓塞满意.13例行外科手术钳闭.结论:64层CTA能准确评价SAH病因及动脉瘤的特征.对选择治疗方法十分有价值.

  5. Value of 64-slice 3D-CTA in diagnosis and surgical treatment of intracranial aneurysm%64层3D-CTA对颅内动脉瘤诊断及临床评估的应用价值

    江涌; 孙晓川; 朱继; 何朝晖; 阮建; 张晓冬; 唐文渊

    2007-01-01

    目的 通过比较64层3D-CTA与DSA在临床诊断颅内动脉瘤及其评估外科治疗的优缺点,评价64层3D-CTA在颅内动脉瘤诊断及治疗中的临床应用价值.方法 回顾性分析2005年9月至2006年12月期间,重庆医科大学附属第一医院神经外科99例自发性蛛网膜下腔出血患者的临床资料,患者均行3D-CTA检查,分析CTA检查结果并与DSA检查结果比较.结果 99例SAH患者经3D-CTA检查发现动脉瘤70例,其中41例同时接受DSA检查,除1例外,全部证实DSA的发现,DSA所漏诊的1例经手术证实为微小动脉瘤.结论 64层螺旋CTA对颅内动脉瘤的诊断敏感性及特异性高,且能够清楚显示解剖结构,有助于治疗方法的选择和难度的评估.

  6. Assessment of the right ventricular function in patients with chronic obstructive pulmonary disease and cor pulmonale using cardiac 64-slice spiral CT comparing with 1.7 T MRI

    Objective: To assess the right ventricular function in patients with moderate to severe chronic obstructive pulmonary disease (COPD) and eor pulmonale using cardiac 64 MSCT comparing with MRI. Methods: Forty-six patients with COPD determined by pulmonary function test (PFT) were prospectively studied. According to the Global Initiative for COPD classification, the COPD patients were divided into three groups depending on the severity of the disease: mild COPD (16 cases), moderate COPD (16 cases) and severe COPD (14 cases). Twenty age-matched subjects were included as the controls. The RV function was assessed by 64-MSCT and 1.5 T cardiac MRI in all four groups. Pearson correlation analysis was used to evaluate the relationship between the right ventricular ejection fraction (RVEF), myocardial mass (MM) and the PFT results in COPD patients. AP value of less than 0.05 was considered statistically significant. End-diastolic volume (EDV), end-systolic volume (ESV), RVEF and MM on MSCT were compared with that on MRI using Pearson correlation analysis. Bland-Airman plot was used to evaluate the correlation between MSCT and MRI. Results: The RVEF was (51.6 ± 5.6)% in mild COPD, (49.8 ± 6.0)% in moderate COPD, (39.4 ± 7.2)% in severe COPD, and (53 ± 5.9)% in controls, respectively. The MM was (44.5 ± 5.4) g in mild COPD, (49.6 ± 5.0) g in moderate COPD, (57.1 ± 3.4) g in severe COPD, and (40.8 ± 3.9) g in controls, respectively. The EDV was (139.9 ± 25.0), (130.2 ± 21.2), (107.6 ± 18.4) and (149.2 ± 27.9) ml, the SV was (72.1 ± 16.1), (64.3 ± 11.0), (42.5 ± 16.5) and (77.0 ± 11.7) ml in four groups, respectively. The values of RVEF and RVEDV were significantly lower in severe COPD than that in mild COPD, moderate COPD and controls (FRVEF=143, FRVEDV=38.07, PRVEF= 1.03, FEDV=3.22, FEFV=0.44, FSV=2.77, P>0.05). The MM of the RV was significantly different between controls and the other three groups (F=66.34, P<0.01). All parameters of the RV function on cardiac CT were correlated well with that on cardiac MRI. The MM of the RV showed moderate correlation (r=0.82), RV volumes and RVEF significant correlation (r=0.98 and 0.97 for RV EDV and RV ESV, r=0.95 for RVEF, respectively). A strong correlation between MSCT and MRI for the assessment of RV function was also found using Bland-Altman plot. The correlation was excellent between the MSCT results and forced expiratory volume in 1 sec (r=0.781 for RVEF, r=-0.824 for RV MM) in COPD patients. Conclusions: Cardiac MSCT can accurately assess the RV size and function in comparison to MRL Patients with severe COPD have RV dysfunction. (authors)

  7. 64排CT与全景牙片在埋伏牙诊断中的应用%Diagnositic Value of 64-Slice CT and Intraoral Digital Dental Radiography Technique in Embedded Teeth

    陈殿森; 陈望; 滑炎卿

    2011-01-01

    目的:评价64排螺旋CT与口腔全景X线牙片对上颌前部埋伏牙诊断及定位的应用价值.方法:对42例全景X线牙片疑上颌埋伏牙患者行64排螺旋CT扫描,并应用64排螺旋CT图像后处理功能,做三维重建和多层面重建,获取相应牙体的任意平面、任意方位图像.结果:42例患者,38例为上颌前部埋伏牙,25例埋伏牙位于腭侧,9例埋伏牙位于唇侧,4例埋伏牙牙根位于腭侧,而牙冠位于唇侧,经手术证实,符合率100%.结论:多排螺旋CT对儿童上颌埋伏牙能做出精确定位,对上颌埋伏牙诊断及定位的价值优于全景数字X线牙片,可作为上颌埋伏牙临床外科治疗及正畸治疗前的重要检查方法.%Objective: To compare the clinic application of multirow spiral CT (MSCT) and intraoral digital dental radiography technique in location with embedded teeth of children. Methods: Forty-two children suspected for embedded teeth were examined by MSCT and intraoral digital dental radiography technique with multiplanar reformation (MPR) and three dimensional (3D) reconstruction of MSCT. Results: A total of 38 cases of embedded teeth were diagnosed, including 25 embedded teeth located in palate sides, 9 in lip sides, and 4 cases of which the teeth root located in palate sides, and the teeth crown located in lip sides. According to the resluts of surgery, the accurate rate was 100%. Conclusion; Multirow spiral CT can accurately locate embedded teeth of children, and have an obvious advantage over the intraoral digital dental radiography technique in diagnosis and locating of embedded teeth. It is an important method to be applied in examing embedded teeth in upper jaw.

  8. Evaluation of early coronary graft patency after coronary artery bypass graft surgery using multislice computed tomography angiography

    Raissi Kamal

    2009-12-01

    Full Text Available Abstract Background Coronary artery bypass graft (CABG surgery is the standard of care in the treatment of advanced coronary artery disease, and its long-term results are affected by the failure of bypass grafts. The aim of the present study was to evaluate the early patency rate in coronary bypass grafts. Methods A total of 107 consecutive patients who underwent CABG were included in this study. Early graft patency was evaluated via computed tomography (CT angiography in the first week after surgery. Results There were a total of 366 grafts, comprised of 250 venous grafts and 116 arterial grafts. Multi-slice CT detected acute graft occlusions in 32 (8.7% of all the grafts, including 26 (10% of the 250 venous grafts and 6 (5% of the 116 arterial grafts. The patency rates obtained were 97.3% for the left internal mammary (IMA grafts, 50% for the radial artery grafts, and 50% for the right IMA grafts. Additionally, 107 (96.4% grafts to the left anterior descending artery (LAD were classified as patent, whereas 1 (30% of the 3 grafts in the left circumflex (LCX region and 1 (50% of the 2 grafts in the right coronary artery (RCA territory were found to be occluded. In the venous category, 8 (13.7% of the 58 grafts to LAD were found to be occluded. In the LCX region, 9 (8.5% of the 106 grafts were classified as occluded, while the remaining 97 (91.5% grafts were patent. The venous grafts to RCA were occluded in 9 (10.4% of the 86 grafts. Amongst the multiple preoperative, intraoperative, and postoperative factors, pump time was significantly longer in the patients with occluded grafts than in those with patent grafts (P = 0.04. Conclusion The IMA grafts had the highest early patency rate amongst the coronary bypass grafts. However, the other arterial grafts were associated with a high rate of acute occlusions.

  9. Computational tools and methods for objective assessment of image quality in x-ray CT and SPECT

    Palit, Robin

    Computational tools of use in the objective assessment of image quality for tomography systems were developed for computer processing units (CPU) and graphics processing units (GPU) in the image quality lab at the University of Arizona. Fast analytic x-ray projection code called IQCT was created to compute the mean projection image for cone beam multi-slice helical computed tomography (CT) scanners. IQCT was optimized to take advantage of the massively parallel architecture of GPUs. CPU code for computing single photon emission computed tomography (SPECT) projection images was written calling upon previous research in the image quality lab. IQCT and the SPECT modeling code were used to simulate data for multi-modality SPECT/CT observer studies. The purpose of these observer studies was to assess the benefit in image quality of using attenuation information from a CT measurement in myocardial SPECT imaging. The observer chosen for these studies was the scanning linear observer. The tasks for the observer were localization of a signal and estimation of the signal radius. For the localization study, area under the localization receiver operating characteristic curve (A LROC) was computed as AMeasLROC = 0.89332 ± 0.00474 and ANoLROC = 0.89408 ± 0.00475, where "Meas" implies the use of attenuation information from the CT measurement, and "No" indicates the absence of attenuation information. For the estimation study, area under the estimation receiver operating characteristic curve (AEROC) was quantified as AMeasEROC = 0.55926 ± 0.00731 and ANoEROC = 0.56167 ± 0.00731. Based on these results, it was concluded that the use of CT information did not improve the scanning linear observer's ability to perform the stated myocardial SPECT tasks. The risk to the patient of the CT measurement was quantified in terms of excess effective dose as 2.37 mSv for males and 3.38 mSv for females. Another image quality tool generated within this body of work was a singular value

  10. Grid Computing

    2016-05-01

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

  11. Cloud Computing