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Sample records for 64-slice spiral ct

  1. 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)

  2. 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.

  3. 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)

  4. 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)

  5. 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)

  6. 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

  7. 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.

  8. 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)

  9. 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

  10. 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)

  11. 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)

  12. 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)

  13. 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

  14. 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

  15. 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

  16. 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

  17. 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

  18. 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

  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

    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. 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.)

  1. 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

  2. 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.

  3. 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。

  4. 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。

  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. 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.

  7. 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。

  8. 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.

  9. 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

  10. 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

  11. 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

  12. 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

  13. 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

  14. 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

  15. 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.

  16. 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.

  17. 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

  18. 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

  19. 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

  20. 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.

  1. 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.)

  2. 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.)

  3. 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.

  4. 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

  5. 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

  6. 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.

  7. 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.)

  8. 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.)

  9. 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

  10. 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.

  11. 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

  12. 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

    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)

  13. 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.

  14. 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.)

  15. 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.)

  16. 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.

  17. 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

  18. 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

  19. 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

  20. 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...

  1. 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.

  2. 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).

  3. 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

  4. 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)

  5. 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...

  6. 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.

  7. 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.

  8. 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.

  9. 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.

  10. 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.

  11. 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.)

  12. 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)

  13. 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

  14. 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.

  15. 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...

  16. 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

  17. 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.)

  18. 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.)

  19. 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

  20. 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

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

    Murphy, David J., E-mail: 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

  2. 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)

  3. 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.)

  4. 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.

  5. 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.

  6. 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.

  7. 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).

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

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

    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.

  9. 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

  10. 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.

  11. 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)

  12. 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.

  13. 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.)

  14. 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.)

  15. 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.)

  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. 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.)

  18. 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.)

  19. 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

  20. 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.

  1. 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.

  2. 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...

  3. 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.

  4. 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

  5. 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

  6. 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

  7. 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...

  8. 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.

  9. 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.

  10. 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

  11. Spiral CT of Non-Graft Post Cardiac Surgery Complications: A Pictorial Essay

    S. Shirani

    2010-06-01

    Full Text Available Spiral CT is a rapidly growing method for noninvasive visualization of post-operative complications, including post-operative complications in CABG (coronary artery bypass graft. In the recent years, several different, yet more efficient types have been introduced with progressive improvement in the diagnostic accuracy in the detection of post-operative complications. The introduction of 64-slice technology, which allows high resolution as well as reconstructed images, has resulted in further progress in the diagnostic process. This kind of diagnostic equipment will spread rapidly in the world. Although studies with large numbers of patients regarding spiral CT as a routine diagnostic method have not been reported, there is great need for it all over the world. In this article, we intend to review the spiral CT findings of non-graft complications in patients after cardiac surgery.

  12. 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)

  13. Subsecond spiral CT: new developments

    X-ray computerized tomography (CT) scanning with continuous patient transport has been established under the name spiral CT since several years as the standard clinical examination procedure. Presently this technique is being improved dramatically with respect to scan speed, temporal response and z-axis resolution. This is achieved by the use of latest technical developments: rotation speed up to 2 s-1 and multi-row detector array systems. Today detector systems with M = 4 simultaneously measured slices are available. We report about recent investigations on new algorithms that are based on multi-slice spiral data. It is shown that the new technology not only provides significant reduction in overall scan times and thereby of the CT scanner's X-ray tube load; beyond that, the new technology makes CT imaging of the beating heart with high level image quality feasible in standard clinical routine. (author)

  14. Groove Pancreatitis: Spiral CT Findings

    To describe the spiral CT findings of groove pancreatitis, a little known entity, and to review its differential diagnosis. We present 8 cases of groove pancreatitis. or pancreatitis affecting the groove between pancreatic head, duodenum and common bile duct, all studied with spiral CT. For two cases, in which were performed cephalic duodenopancreatectomies, anatomopathological correlations were available. In the other 6 cases, radiological follow-ups of anywhere between 5 and 36 months were utilized. In all eight cases, spiral CT showed expansion and increasing density of lipids within the groove with poor contrast enhancement indicative of the fibrous nature of this pathology, and associated with cystic areas in its interior and/or the duodenal wall. the pancreatic head was unaffected in pure forms of groove pancreatitis, and hypodense areas were observed in zones of cephalic segmental enhancement. Knowledge of this little known form of chronic pancreatitis, and the radiological findings that permit its diagnosis are important for the radiologist since its differential diagnosis includes neoplasia of the peri-ampullary region. (Author) 6 refs

  15. [Spiral CT angiography in practice].

    Pavcec, Zlatko; Zokalj, Ivan; Rumboldt, Zoran; Pal, Andrej; Saghir, Hussein; Ozretić, David; Latin, Branko; Perhoć, Zeljka; Marotti, Miljenko

    2005-01-01

    Incidence of vascular diseases and development of new radiologic techniques in the last three decades has given strong impuls for introduction of non-invasive vascular diagnostic methods. Thanks to the introduction of Doppler ultrasound, new types of computed tomography (CT) and magnetic resonance (MR) scanners, non-invasive vascular diagnostic methods are replacing conventional invasive (catheter) angiographic methods. Computed tomographic angiography (CTA) is a noninvasive vascular diagnostic method based on continuous scanning with CT scanner during intravenous application of contrast material. Performing of CTA is possible after introduction of spiral CT technique whose characteristics are short imaging time and volumetric data acquisition. The main goal of this article, based on our experiences, is to review the role of CTA, performed on single-slice CT scanner, in managment of patients with vascular pathology. PMID:16145870

  16. 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.

  17. 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.

  18. 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.

  19. 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

  20. Pulmonary metastases. Spiral CT with surgical correlation

    Kuriyama, Keiko; Hosomi, Naohiro; Sawai, Yuka [Osaka Prefectural Center for Adult Diseases (Japan)] [and others

    1995-01-01

    Spiral volumetric computed tomography (CT) with single breath-hold technique is clearly sensitive than conventional sequential CT in the detection of pulmonary nodules. The sensitivity of spiral volumetric CT for detection of pulmonary metastases in 27 patients schedule for thoracotomy and curative resection of lesions was evaluated with prospective study. The spiral volumetric CT protocol consisted of a 10 mm/sec table feed during 24-second breath hold with 10-mm section thickness using 360deg linear interpolation (n=13), and 5-mm section thickness using 180deg linear interpolation (n=14). Of 145 resected metastases, 86 (59%) were depicted by spiral volumetric CT. Seventy-four (99%) of 75 large nodules ({>=}5 mm in diameter) were depicted, however, only 12 (17%) of 70 small nodules (<5 mm in diameter) were depicted by spiral volumetric CT. Future large prospective studies evaluating individual malignancies are needed to assess the impact on long-term survival of early detection of pulmonary metastases with spiral volumetric CT. (author).

  1. Spiral CT of pancreas. Clinical comparison with conventional CT and dynamic CT; Spiral-CT des Pankreas. Klinischer Vergleich mit der konventionellen CT und der dynamischen CT

    Hidajat, N. [Strahlenklinik und Poliklinik, Universitaetsklinikum Rudolf Virchow, Freie Univ. Berlin (Germany); Schedel, H. [Strahlenklinik und Poliklinik, Universitaetsklinikum Rudolf Virchow, Freie Univ. Berlin (Germany); Vogl, T. [Strahlenklinik und Poliklinik, Universitaetsklinikum Rudolf Virchow, Freie Univ. Berlin (Germany); Schroeder, R.J. [Strahlenklinik und Poliklinik, Universitaetsklinikum Rudolf Virchow, Freie Univ. Berlin (Germany); Keck, H. [Chirurgische Klinik und Poliklinik, Universitaetsklinikum Rudolf Virchow, Freie Univ. Berlin (Germany); Feix, R. [Strahlenklinik und Poliklinik, Universitaetsklinikum Rudolf Virchow, Freie Univ. Berlin (Germany)

    1995-07-01

    Spiral CT is compared with the dynamic CT and the conventional CT with regard to the enhancement of the pancreas and peripancreatic vessels and the visualisation of anatomic details. Compared with dynamic CT, spiral CT of the pancreatic region in the arterial phase (flow 4 ml/s, delay 15-18 s) leads to a stronger contrast of the peripancreatic vessels and the pancreas (108 vs. 86 HU). In the following spiral CT of the upper abdomen (flow 1 ml/s, delay 70 s), a high enhancement of both arteries and veins could be achieved. Intrapancreatic structures and peripancreatic vessels were better seen in the spiral CT than in the conventional CT. The combination of spiral CT of the pancreatic region in the arterial perfusion phase and spiral CT of the upper abdomen in the arterial-venous phase enables an optimal enhancement of the pancreas and the abdominal vessels and a reliable visualisation of anatomic details. (orig./MG) [Deutsch] Es werden die Spiral-CT, die dynamische CT (Dynamic Sequence) und die konventionelle CT im Hinblick auf die Kontrastierung der Pankreasregion und die Visualisierung von anatomischen Details miteinander verglichen. Die Spiral-CT der Pankreasregion fuehrte im Vergleich zur dynamischen CT (Fluss 4 ml/s, Verzoegerung 15-18 s) zu einer hoeheren Dichtesteigerung der peripankreatischen Arterien und des Pankreas (108 vs. 86 HE). Bei der anschliessend durchgefuehrten Spiral-CT des Oberbauches (Fluss 1 ml/s, Verzoegerung 70 s) wurde ein hoher Kontrast sowohl der Arterien als auch der Venen erreicht. Mit dieser gelang eine bessere Erkennbarkeit von intrapankreatischen Strukturen und peripankreatischen Gefaessen als mit der konventionellen CT. Die Kombination der Spiral-CT des Pankreas in der arteriellen Perfusionsphase und der Spiral-CT des Oberbauches in der arteriell-venoesen Phase ermoeglicht eine optimale Kontrastierung des Pankreas und der Oberbauchgefaesse sowie eine zuverlaessige Erfassung von anatomischen Details. (orig./MG)

  2. 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)

  3. Imaging of head and neck tumors -- methods: CT, spiral-CT, multislice-spiral-CT

    Spiral-CT is standard for imaging neck tumors. In correspondence with other groups we routinely use spiral-CT with thin slices (3 mm), a pitch of 1.3-1.5 and an overlapping reconstruction increment (2-3 mm). In patients with dental fillings a short additional spiral parallel to the corpus of the mandible reduces artifacts behind the dental arches and improves the diagnostic value of CT. For the assessment of the base of the skull, the orbital floor, the palate and paranasal sinuses an additional examination in the coronal plane is helpful. Secondary coronal reconstructions of axial scans are helpful in the evaluation of the crossing of the midline by small tumors of the tongue base or palate. For an optimal vascular or tissue contrast a sufficient volume of contrast medium and a start delay greater than 70-80 s are necessary. In our opinion the best results can be achieved with a volume of 150 ml, a flow of 2.5 ml/s and a start delay of 80 s. Dynamic enhanced CT is only necessary in some special cases. There is clear indication for dynamic enhanced CT where a glomus tumor is suspected. Additional functional CT imaging during i-phonation and/or Valsalva's maneuver are of great importance to prove vocal cords mobility. Therefore, imaging during i-phonation is an elemental part of every thorough examination of the hypopharynx and larynx region. Multislice-spiral-CT allows almost isotropic imaging of the head and neck region and improves the assessment of tumor spread and lymph node metastases in arbitrary oblique planes. Thin structures (the base of the skull, the orbital floor, the hard palate) as well as the floor of the mouth can be evaluated sufficiently with multiplanar reformations. Usually, additional coronal scanning is not necessary with multislice-spiral-CT. Multislice-spiral-CT is especially advantageous in defining the critical relationships of tumor and lymph node metastases and for functional imaging of the hypopharynx and larynx not only in the

  4. Imaging of head and neck tumors -- methods: CT, spiral-CT, multislice-spiral-CT

    Baum, Ulrich E-mail: baum@idr.med.uni-erlangen.de; Greess, Holger; Lell, Michael; Noemayr, Anton; Lenz, Martin

    2000-03-01

    Spiral-CT is standard for imaging neck tumors. In correspondence with other groups we routinely use spiral-CT with thin slices (3 mm), a pitch of 1.3-1.5 and an overlapping reconstruction increment (2-3 mm). In patients with dental fillings a short additional spiral parallel to the corpus of the mandible reduces artifacts behind the dental arches and improves the diagnostic value of CT. For the assessment of the base of the skull, the orbital floor, the palate and paranasal sinuses an additional examination in the coronal plane is helpful. Secondary coronal reconstructions of axial scans are helpful in the evaluation of the crossing of the midline by small tumors of the tongue base or palate. For an optimal vascular or tissue contrast a sufficient volume of contrast medium and a start delay greater than 70-80 s are necessary. In our opinion the best results can be achieved with a volume of 150 ml, a flow of 2.5 ml/s and a start delay of 80 s. Dynamic enhanced CT is only necessary in some special cases. There is clear indication for dynamic enhanced CT where a glomus tumor is suspected. Additional functional CT imaging during i-phonation and/or Valsalva's maneuver are of great importance to prove vocal cords mobility. Therefore, imaging during i-phonation is an elemental part of every thorough examination of the hypopharynx and larynx region. Multislice-spiral-CT allows almost isotropic imaging of the head and neck region and improves the assessment of tumor spread and lymph node metastases in arbitrary oblique planes. Thin structures (the base of the skull, the orbital floor, the hard palate) as well as the floor of the mouth can be evaluated sufficiently with multiplanar reformations. Usually, additional coronal scanning is not necessary with multislice-spiral-CT. Multislice-spiral-CT is especially advantageous in defining the critical relationships of tumor and lymph node metastases and for functional imaging of the hypopharynx and larynx not only in the

  5. Spiral CT of pancreas. Clinical comparison with conventional CT and dynamic CT

    Spiral CT is compared with the dynamic CT and the conventional CT with regard to the enhancement of the pancreas and peripancreatic vessels and the visualisation of anatomic details. Compared with dynamic CT, spiral CT of the pancreatic region in the arterial phase (flow 4 ml/s, delay 15-18 s) leads to a stronger contrast of the peripancreatic vessels and the pancreas (108 vs. 86 HU). In the following spiral CT of the upper abdomen (flow 1 ml/s, delay 70 s), a high enhancement of both arteries and veins could be achieved. Intrapancreatic structures and peripancreatic vessels were better seen in the spiral CT than in the conventional CT. The combination of spiral CT of the pancreatic region in the arterial perfusion phase and spiral CT of the upper abdomen in the arterial-venous phase enables an optimal enhancement of the pancreas and the abdominal vessels and a reliable visualisation of anatomic details. (orig./MG)

  6. 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.

  7. 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.

  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. Assessment of spiral CT pneumocolon in preoperative colorectal carcinoma

    Can-Hui Sun; Zi-Ping Li; Quan-Fei Meng; Shen-Ping Yu; Da-Sheng Xu

    2005-01-01

    AIM: To investigate the value of spiral CT pneumocolon in preoperative colorectal carcinoma.METHODS: Spiral CT pneumocolon was performed prior to surgery in 64 patients with colorectal carcinoma. Spiral CT images were compared to specimens from the resected tumor.RESULTS: Spiral CT depicted the tumor in all patients.Comparison of spiral CT and histologic results showed that the sensitivity and specificity were 95.2%, 40.9% in detection of local invasion, and 75.0%, 90.9% in detection of lymph node metastasis. Compared to the Dukes classification,the disease was correctly staged as A in 6 of 18 patients,as B in 18 of 23, as C in 10 of 15, and as D in 7 of 8. Overall,spiral CT correctly staged 64.1% of patients.CONCLUSION: Spiral CT pneumocolon may be useful in the preoperative assessment of patients with colorectal carcinoma as a means for assisting surgical planning.

  10. Physical performance characteristics of spiral CT scanning

    This paper reports on CT scanning in spiral geometry that has recently been introduced; it is achieved by continuous patient transport during continuous multirotational data acquisition. While the advantages for clinical studies are obvious, the physical performance characteristics have to be investigated to detail. Phantom studies and clinical studies have been performed on a Somatom Plus (Siemens AG, Erlangen, West Germany). In addition, simulation studies have been carried out to estimate section-sensitivity profiles, noise, and artifact behavior. RESULTS: Many of the standard physical performance characteristics (eg, spatial resolution, image uniformity, dose values, and contrast) are not affected by spiral CT scanning. Artifact behavior, pixel noise, and section-sensitivity profiles are changed as a function of table speed; the changes agree with predictions by simulation. Pixel noise is reduced by about a factor of 0.8 in reconstruction by an interpolation procedure. Sensitivity profiles are smoothed because the original profile is convolved with the object motion function. Drawbacks of spiral CT with respect to image quality are not significant. The advantages offered by continuous canning and arbitrary retrospective selection of section positions within the scanned volume clearly more than compensate for the slight disadvantages

  11. 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

  12. 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

  13. Functional spiral CT of the larynx; Funktionelle Spiral-CT des Kehlkopfes

    Kloeppel, R. [Universitaetsklinikum Leipzig (Germany). Zentrum fuer Radiologie; Auerbach, K. [Universitaetsklinikum Leipzig (Germany). Zentrum fuer Radiologie; Kamprad, F. [Universitaetsklinikum Leipzig (Germany). Zentrum fuer Radiologie; Meister, E.F. [Universitaetsklinikum Leipzig (Germany). Klinik fuer Hals-Nasen-Ohrenkrankheiten

    1996-05-01

    Imaging of the larynx by computed tomography has reached a new quality through spiral CT. Its significance for evaluation of vocal cords function is examined with 10 patients with glottic tumours before, during and after radiation therapy. The spiral CT procedure which complements laryngoscopy is described: Gantry tilt 10 caudal, two spiral CT starting at the cricoid cartilage with 3 mm slice thickness and pitch 1, one with flat breathing and one with `i` phonation; overlapping reconstruction with large zoom factor, secondary reconstruction image reformating. (orig.) [Deutsch] Die computertomographische Darstellung des Kehlkopfes hat durch die Spiraltechnik eine neue Qualitaet erreicht. Ihre Bedeutung fuer die Funktionsbeurteilung der Stimmlippen wird an 10 Patienten mit glottischen Tumoren vor, waehrend und nach Strahlentherapie untersucht. Das die Laryngoskopie ideal ergaenzende Verfahren der Spiral-CT in Funktionsstellung wird vorgestellt: Gantrykippung von 10 nach ventral, zwei Spiraluntersuchungen vom Ringknorpel beginnend nach kranial in 3 mm Schichtdicke und Tischgeschwindigkeit erstens in ruhiger Atmung und zweitens in `i`-Phonation, 1 mm ueberlappende Rekonstruktion mit hohem Zoomfaktor, obligate Sekundaerschnittrekonstruktionen. (orig.)

  14. 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.

  15. 3D Reconstruction in Spiral Multislice CT Scans

    M. Ghafouri

    2005-01-01

    Introduction & Background: The rapid development of spiral (helical) computed tomography (CT) has resulted in exciting new applications for CT. One of these applications, three-dimensional (3D) CT with volume ren-dering, is now a major area of clinical and academic interest. One of the greatest advantages of spiral CT with 3D volume rendering is that it provides all the necessary information in a single radiologic study (and there-fore at the lowest possible price) in cases that previousl...

  16. 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.

  17. Acute appendicitis in unenhanced spiral CT: Diagnostic luxury or benefit?

    Purpose: To evaluate the diagnostic accuracy of thin collimated unenhanced spiral-CT in patients with clinically suspected acute appendicitis and to determine the impact on patient management and overall costs. Method: Unenhanced focussed appendiceal spiral-CT was performed in 56 patients (23 women and 33 men) with clinically suspected acute appendicitis. Scans were obtained from the L4 level to the symphysis pubis using 5 mm collimation, 7.5 mm table feed (pitch 1.5) and 4 mm increment without i.v., oral, or rectal contrast material. Prospective diagnoses based on CT findings were compared with surgical (and histopathological) results and clinical follow-up. The effect of spiral-CT on patient management and clinical pressources was assessed. Results: 29 patients (10 women and 19 men) underwent appendectomy. Unenhanced spiral-CT was an accurate impaging technique for the initial examination of patients with suspected acute appendicitis with a sensitivity of 95.4% and a specificity 100%, an accuracy of 98.2%, a positive predictive value of 100%, and a negative predictive value of 97.1%. In 27 patients with no evidence of acute appendicitis, an alternative diagnosis could be made in 24 patients by unenhanced spiral-CT. Conclusion: Unenhanced spiral-CT is an accurate test to diagnose or to exclude acute appendicitis. Routine appendiceal spiral-CT can improve medical care and reduce the overall costs for patients suspected of having acute appendicitis. (orig.)

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

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

    2011-01-01

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

  19. 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

  20. 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.

  1. 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.

  2. Dosimetry in dental radiology. Dentascan spiral CT versus panoramic radiography

    The study compares the doses absorbed by the dentomaxillary area in spiral CT and panoramic examinations. The dose measurements demonstrate that patients receive smaller doses with panoramic radiography than with spiral CT with Dentascan. After following for some variations from instrumental differences, they are in substantial agreement with literature data. Further investigations are needed considering the radiobiological risk related to the growing spread of Dentascan examinations

  3. Negative spiral CT in acute pulmonary embolism

    Purpose: To retrospectively evaluate the clinical outcome of non-anticoagulated patients with clinically suspected acute pulmonary embolism (PE) and no symptoms or signs of deep venous thrombosis (DVT) following a negative contrast medium-enhanced spiral CT of the pulmonary arteries (s-CTPA). Material and Methods: During a 24-month period, 739 of 751 patients underwent s-CTPA with acceptable diagnostic quality for clinically suspected acute PE. All patients who had a CT study not positive for PE were followed up with a questionnaire, a telephone interview and review of all medical reports, including autopsies and death certificates for any episodes of venous thromboembolism (VTE) during a 3-month period. Results: PE was diagnosed in 158 patients. Of the remaining 581 patients with a negative s-CTPA, 45 patients were lost to follow-up. 88 patients were excluded because of anticoagulation treatment (cardiac disorder n=32, chronic VTE or acute symptomatic DVT n=31, PE diagnosed at pulmonary angiography n=1, thrombus prophylaxis during diagnostic work-up or other reasons than VTE n=24) and 7 patients undergoing lower extremity venous studies because of symptoms of DVT (all negative). Thus, 441 patients with a negative s-CTPA and no DVT symptoms, venous studies or anticoagulant treatment constituted the follow-up cohort. Four of these patients had proven VTE (all PE) during the 3-month follow-up period. Two of the PE episodes contributed to the patient's death. Conclusion: Patients with clinically suspected acute PE, no symptoms or signs of DVT and a negative single slice s-CTPA using 3-5 mm collimation, may safely be left without anticoagulation treatment unless they are critically ill, have a limited cardiopulmonary reserve and/or if a high clinical suspicion remains

  4. Spiral CT Scan for Detecting Coronary Artery Stenosis

    A. Soltani Shirazi

    2005-07-01

    Full Text Available Background/ Objective: Coronary vessel calcification is an obvious sign of atherosclerotic disease of coronary arteries. Electron beam CT scan is currently the imaging modality of choice for assessing coronary artery calcifications. However, its high cost makes it unavailable to a large number of medical centers. We carried out this study to compare the diagnostic yield of spiral CT scans as an alternative, to coronary angiography. Patients and Methods: A hundred patients suspicious of having coronary artery disease (CAD underwent angiography as well as spiral CT scan of the heart. On CT scan, calcification of >90 Hounsfield on a surface area of >0.5 mm2, anatomically superimposed on coronary arteries were highlighted as calcified areas using the volumetric feature of the scanner. The findings were compared to angiographic results. Results: Of 100 patients enrolled (62 males, 69 had coronary artery obstruction (>50% stenosis on angiography. Angiography was normal in the rest. Spiral CT scan had a sensitivity of 94% and a specificity of 61% for the diagnosis of coronary artery disease. The PPV and NPV were 84% and 79%, respectively. Among the coronary arteries, LAD findings had the highest sensitivity (92% and the lowest specificity (65% in the diagnosis of CAD. With age, spiral CT scan had more sensitivity and less specificity for CAD. Conclusion: Detecting calcification by spiral CT scanning could be a useful non-invasive method for diagnosis and evaluation of coronary artery stenosis.

  5. 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...

  6. 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 ...

  7. 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

  8. Dynamic study of the larynx with spiral CT

    Park, Jong Yeon; Choi, Chang Ho; Yoon, Chi Soon; Kim, Yoon Gyoo; Nam, Sang Hwa; Kim, Kun Il; Kim, Byung Soo; Wang, Soo Guen [College of Medicine, Pusan National University, Busan (Korea, Republic of)

    1994-03-15

    It is essential to know the functional and morphologic changes of the larynx in the evaluation of laryngeal lesions. Conventional CT which has relatively long examination time is not suitable for this aim. The purposes of this study are to evaluate the capability of spiral CT in the dynamic study of the larynx and to know whether this new technique can replace conventional laryngography or not. Five healthy volunteers and 20 patients with laryngeal lesions underwent spiral dynamic CT scans with 3-dimensional reconstruction of the mucosal surface. A series of spiral CT scans were done while the volunteers performed various laryngeal positions to obtain the functional and morphologic information. The maneuvers used were: quite breathing, 'E' phonation, Valsalva maneuver, modified Valsalva maneuver, and a new method of our own, 'modified breath holding' technique. The patients were scanned when in quite breathing. Additional scans were obtained by using the 'modified breath holding' technique. The dynamic study with spiral CT could provide high resolutional images which nicely depicted the mobility of vocal cords and the mucosal changes of the laryngeal cavity in both healthy volunteer and patient groups. In patient group, the new 'modified breath holding' technique was easier and more reproducible than other maneuvers. Spiral CT allows a dynamic study of the larynx and can be a new alternative of laryngography.

  9. Multislice spiral CT for the diagnostics of pancreatic tumors; Mehrzeilen-Spiral-CT in der Diagnostik von Pankreastumoren

    Baum, U.; Lell, M.; Noemayr, A.; Greess, H.; Bautz, W. [Erlangen-Nuernberg Univ., Erlangen (Germany). Inst. fuer Diagnostische Radiologie; Wolf, H. [Erlangen-Nuernberg Univ., Erlangen (Germany). Inst. fuer Medizinische Physik; Brunner, T. [Erlangen-Nuernberg Univ., Erlangen (Germany). Klinik und Poliklinik fuer Strahlentherapie

    1999-11-01

    Purpose. Investigation of the capabilities of MSCT and its value for the staging of pancreatic carcinomas. Methods. 50 Patients with suspected pancreatic carcinoma were examined with a biphasic multislice-spiral-CT protocol: Slice collimation 4x1 mm, Pitch 3.5-4 mm. After administration of 120 ml contrast medium and 50 ml NaCl with a flow rate of 3.0 ml/s the examination was started with a delay of 40 s (pancreatic phase) and 80 s (portalvenous phase). Results: Multislice spiral CT allows the examination of the whole upper abdomen with nearly isotropic data sets. This is the premise for the optimal assessment of the tumor extent in all planes, excellent demarcation of the tumor against the adjacent vessels and organs and the demarcation of small peripancreatic lymph nodes. Conclusions. Multislice spiral CT and the use of interactive multiplanar reconstructions improve the staging of pancreatic cancer. (orig.) [German] Ziel unserer Untersuchungen war es, die Moeglichkeiten der Mehrzeilen-Detektor-Spiral-CT und ihre Bedeutung fuer das Staging von Pankreastumoren zu evaluieren. Bei insgesamt 50 Patienten, bei denen der Verdacht auf ein Pankreaskarzinom bestand, wurde im Rahmen der Tumorstagings ein biphasisches hochaufgeloestes Mehrzeilen-Spiral-CT mit einer Schichtkollimation von 4x1 mm, einem Pitch von 3,5-4, 120 ml Kontrastmittel, 50 ml 0,9%NaCl-Bolus, 3,0 ml/s Fluss und einem Startdelay von durchschnittlich 40 s (Pankreasparenchymphase) und 80 s (portalvenoese Phase) durchgefuehrt. Die Mehrzeilen-Spiral-CT ist in der Lage die gesamte Pankreasloge und auch die angrenzenden Organe mit hoher Ortsaufloesung in allen Raumebenen abzubilden. Die nahezu isotrope multiplanare Bildgebung erlaubt die vollstaendige Erfassung der Tumorausdehnung in allen Raumebenen und eine bessere Abgrenzung der Tumoren gegenueber dem angrenzenden Fettgewebe, den benachbarten Organen (Gefaesse, Duodenum, Magen) und einen sichereren Nachweis von peripankreatischen Lymphknoten. Die Mehrzeilen-Spiral-CT

  10. Diagnosis of seat belt injury using spiral CT

    Seat belt injury (s.b.i.) arises from not properly applied seat belts in case of car accidents. The importance of spiral CT for the diagnosis of s.b.i., especially of hidden traumatic lesions, will be demonstrated. Our experience includes 9 children in the age of 4 to 13 years suffering from life-threatening s.b.i. After life-saving treatment we took a spiral CT (Somatom plus S): First spiral CT, 10 mm slice thickness, without contrast medium (c.m.) and second spiral CT, 5 mm slice thickness, start delay 35-45 s after a large volume of c.m. Of these, 8 of 9 children survived. Besides bruising signs, head injuries, and knee point lesions in 4 of 9 cases, a combination of uptured duodenum, ruptured liver or spleen, and chance fractures of the spine was found which is typical for s.b.i. In the remaining 5 cases, two of the lesions were combined. Rupture of the small bowel was manifested mainly as the discrete finding of free air or inhomogeneous ascites with a high density (bowel contents mixed with blood). Not only the emergency doctor but also the radiologist should take into account the complexity of seat belt injuries. Spiral CT is the imaging method of choice in the case of polytraumatic children. (orig.)

  11. 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.

  12. Spiral CT in patients with chronic thromboembolic lung disease; Spiral-CT bei chronisch-thromembolischer Lungenerkrankung

    Kontrus, M. [Universitaetsklinik fuer Radiodiagnostik, Ludwig Boltzmann Institut fuer Radiologisch-Physikalische Tumordiagnostik, Wien (Austria); Bankier, A.A. [Universitaetsklinik fuer Radiodiagnostik, Ludwig Boltzmann Institut fuer Radiologisch-Physikalische Tumordiagnostik, Wien (Austria); Winkelbauer, F.W. [Universitaetsklinik fuer Radiodiagnostik, Ludwig Boltzmann Institut fuer Radiologisch-Physikalische Tumordiagnostik, Wien (Austria); Klepetko, W. [Abteilung Herz-Thoraxchirurgie, Universitaetsklinik fuer Chirurgie, Wien (Austria); Lang, I. [Abteilung Kardiologie, Universitaetsklinik fuer Innere Medizin 2, Wien (Austria); Wiesmayr, M.N. [Universitaetsklinik fuer Radiodiagnostik, Ludwig Boltzmann Institut fuer Radiologisch-Physikalische Tumordiagnostik, Wien (Austria); Herold, C.J. [Universitaetsklinik fuer Radiodiagnostik, Ludwig Boltzmann Institut fuer Radiologisch-Physikalische Tumordiagnostik, Wien (Austria)

    1996-06-01

    Chronic thromboembolic pulmonary hypertension (CTEPH) is a rare result of recurrent pulmonary embolism and is treated by pulmonary thromboendarterectomy. Knowledge of the exact location of the thrombi is necessary in planning this operation. To date, pulmonary, angiography is the diagnostic imaging gold standard. Since the introduction of spiral CT excellent vascular opacification of the pulmonary arteries has become feasible, and thrombi in the pulmonary arteries can be visualized directly. Spiral CT is superior to angiography in demonstrating thrombi in the central pulmonary arteries, whereas angiography proves superior to CT in the valuation of abnormalities within segmental arteries. The sensitivity of spiral CT in confirming the diagnosis of CTEPH is reported to be more than 90%. According to the literature and based on our own results, the decision concerning operability is possible on the basis of spiral CT images in more than 80% of patients with CTEPH. Spiral CT as a non-invasive tool may be used for CTEPH screening, for postoperative follow-up after pulmonary thrombendarterectomy and, combined with pulmonary angiography, to optimize operation planning. (orig.) [Deutsch] Die chronisch thrombembolische pulmonale Hypertension (CTEPH) ist ein seltenes Krankheitsbild, das vermutlich eine Folgeerscheinung nach rezidivierenden Pulmonalembolien darstellt. Die chirurgische Pulmonalisthrombendarteriektomie ist heute die Therapieoption der Wahl. Zur Planung dieser Operation ist eine exakte Darstellung der thrombotischen Gefaesswandveraenderungen Voraussetzung. Als diagnostischer Goldstandard gilt bis heute die Pulmonalisangiographie. Die Einfuehrung der Spiral-CT ermoeglichte nun erstmals nichtinvasiv eine gute Kontrastierung der gesamten Pulmonalarterien und damit eine direkte und suffiziente Darstellung der Thromben in zentralen Pulmonalarterien der Pulmonalisangiographie leicht ueberlegen, waehrend dessen die Angiographie eine bessere Darstellung der

  13. Multislice spiral CT of the paranasal sinuses; Mehrschicht-Spiral-CT der Nasennebenhoehlen: Erste Erfahrungen unter besonderer Beruecksichtigung der Strahlenexposition

    Dammann, F.; Bode, A.; Heuschmid, M.; Kopp, A.; Georg, C.; Pereira, P.L.; Claussen, C.D. [Tuebingen Univ. (Germany). Radiologische Universitaetsklinik

    2000-08-01

    Purpose: To evaluate the potential of multislice CT in the diagnosis of the paranasal sinuses. Methods: Dose measurements were performed exposing an Alderson Rando phantom in a four-slice spiral CT (MS-CT) while applying a variety of scan parameters. Additionally, 30 consecutive patients underwent a transversal examination by the MS-CT using 1/1/3.5/0.5 mm spiral parameters and an additional transversal or coronal scan on a conventional single slice spiral CT (SS-CT) with 2/3/1 mm. Coronal reformations of the MS-CT were compared with the primary coronal SS-CT, or coronal reformations of the transversal SS-CT, respectively, with regard to image quality and depiction of relevant anatomical details of the region. Results: Superficial exposure values at the level of the eye lenses as well as for the thyroid gland were superior for MS-CT (3.62 mGy, and 0.12 mGy, resp.) as compared to SS-CT (2.96 mGy, and 0.07 mGy). Image quality was equal or superior for MS-CT as compared to SS-CT in all but one case. Drawbacks of SS-CT, such as dental amalgam artifacts, stair step artifacts or partial volume artifacts did not notably affect the coronal reformations of MS-CT. Conclusions: MS-CT seems to have the potential to replace primary coronal CT of the paranasal sinuses without any loss of image quality, but may even improve the overall diagnostic value. Radiation doses may still have to be reduced. (orig.) [German] Ziel: Erprobung eines Multislice-CT (MS-CT) zur Diagnostik der Nasennebenhoehlen (NNH). Methode: An einem Alderson Rando Phantom wurden Dosismessungen bei der Spiral-CT der NNH mit einem Mehrschicht-CT (MS-CT) unter Verwendung unterschiedlicher Scanparameter durchgefuehrt. Anschliessend wurden 30 konsekutive Patienten an dem MS-CT mit den Spiralparametern 1/1/3,5/0,5 mm und einem konventionellen Einzeilen Spiral-CT (SS-CT; 2/3/1 mm) untersucht. Die koronaren Rekonstruktionen der transversalen MS-CT wurden mit den koronaren Rekonstruktionen bzw. den primaeren koronaren

  14. 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.)

  15. 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

  16. Design Consideration and Reconstruction Method for Double-source Double-multislice Spiral CT

    LIU Zun-gang; ZHAO Jun; ZHUANG Tian-ge

    2007-01-01

    To accelerate the scan speed and improve the image quality, a new type of CT configuration, "doublesource double-multislice spiral CT" (DSDMS-CT), which is based on two sets of single-source multislice spiral CT was proposed with a special reconstruction algorithm.Simulation results using the fan-beam filtered backprojection algorithm with a special interpolation method were presented for both single-source multislice spiral CT and DSDMS-CT.The results of new CT model show that it scans faster than the traditional spiral CT and has a better slice sensitivity profile (SSP) with larger pitch value.

  17. Value of noncontrast spiral CT for suspected acute appendicitis

    To assess the diagnostic accuracy and clinical efficacy of noncontrast spiral CT in patients with suspected acute appendicitis. Over a six-month period, 100 patients with suspected acute appendicitis were prospectively evaluated with noncontrast spiral CT. All scans were obtained from the lower body of L3 to the symphysis pubis, with 5mm or 10mm collimation and pitch of 1 or 1.5, and without intravenous or oral contrast material. Diagnosis was established by means of surgical or clinical follow-up. Prospective diagnosis based on CT findings was compared with surgical results and clinical follow-up. Acute appendicitis was confirmed in 47 of 100 patients. On the basis of the Ct findings, SI patients were prospectively interpreted as positive for appendicitis, but in six the diagnosis was false-positive. Two of the 47 with acute appendicitis were prospectively interpreted as normal. The preoperative diagnosis of acute appendicitis was, thus, 45 true-positive, 47 true-negative, six false-positive and two false-negative yielding a sensitivity of 96%, a specificity of 89%, an accuracy of 92%, a positive predictive value of 88%, and a negative predictive value of 96%. Using CT, an alternative diagnosis was established in 14 patients. Noncontrast spiral CT is a useful technique for diagnosing acute appendicitis. =20

  18. Spiral CT colonography in inflammatory bowel disease

    Tarjan, Zsolt E-mail: tarjan@radi.sote.hu; Zagoni, Tamas; Gyoerke, Tamas; Mester, Adam; Karlinger, Kinga; Mako, Erno K

    2000-09-01

    Objective: Most of the studies on virtual colonoscopy are dealing with the role of detecting colorectal polyps or neoplasms. We have undertaken this study to evaluate the value of CT colonography in patients with colonic Crohn's disease. Methods and material: Five patients (three males, two females, 23-51 years, mean age 42 years) with known (4) or suspected (1) Crohn's disease of the colon underwent fiberoptic colonoscopy and CT colonography in the same day or during a 1-week period. The images were evaluated with the so called zoomed axial slice movie technique and in some regions intra- and extraluminal surface shaded and volume rendered images were generated on a separate workstation. The results were compared to those of a colonoscopy. Results: The final diagnosis was Crohn's disease in four patients and colitis ulcerosa in one. Total examination was possible by colonoscopy in two cases, and with CT colonography in all five cases. The wall of those segments severely affected by the disease were depicted by the axial CT scans to be thickened. The thick walled, segments with narrow lumen seen on CT colonography corresponded to the regions where colonoscopy was failed to pass. Air filled sinus tracts, thickening of the wall of the terminal ileum, loss of haustration pseudopolyps and deep ulcers were seen in CT colonography. Three dimensional (3D) endoluminal views demonstrated pseudopolyps similar to endoscopic images None of the colonoscopically reported shallow ulcerations or aphtoid ulcerations or granular mucosal surface were observed on 2- or 3D CT colonographic images. Conclusion: CT colonography by depicting colonic wall thickening seems to be a useful tool in the diagnosis of Crohn's colitis, which could be a single examination depicting the intraluminal, and transmural extent of the disease.

  19. Spiral CT colonography in inflammatory bowel disease

    Objective: Most of the studies on virtual colonoscopy are dealing with the role of detecting colorectal polyps or neoplasms. We have undertaken this study to evaluate the value of CT colonography in patients with colonic Crohn's disease. Methods and material: Five patients (three males, two females, 23-51 years, mean age 42 years) with known (4) or suspected (1) Crohn's disease of the colon underwent fiberoptic colonoscopy and CT colonography in the same day or during a 1-week period. The images were evaluated with the so called zoomed axial slice movie technique and in some regions intra- and extraluminal surface shaded and volume rendered images were generated on a separate workstation. The results were compared to those of a colonoscopy. Results: The final diagnosis was Crohn's disease in four patients and colitis ulcerosa in one. Total examination was possible by colonoscopy in two cases, and with CT colonography in all five cases. The wall of those segments severely affected by the disease were depicted by the axial CT scans to be thickened. The thick walled, segments with narrow lumen seen on CT colonography corresponded to the regions where colonoscopy was failed to pass. Air filled sinus tracts, thickening of the wall of the terminal ileum, loss of haustration pseudopolyps and deep ulcers were seen in CT colonography. Three dimensional (3D) endoluminal views demonstrated pseudopolyps similar to endoscopic images None of the colonoscopically reported shallow ulcerations or aphtoid ulcerations or granular mucosal surface were observed on 2- or 3D CT colonographic images. Conclusion: CT colonography by depicting colonic wall thickening seems to be a useful tool in the diagnosis of Crohn's colitis, which could be a single examination depicting the intraluminal, and transmural extent of the disease

  20. Spiral CT of hypervascular liver tumors and liver transplants

    This paper evaluates the accuracy of spiral CT with bolus contrast material injection in delineation of hypervascular liver tumors and follow-up of liver transplants. Spiral CT scans were obtained on a Somatom Plus (Siemens) in 35 patients with hypervascular liver tumors (22 hepatocellular carcinoma [HCC], 8 focal nodular hyperplasia, 3 adenomas, 2 metastases) and in 80 patients with liver transplants. A contrast material bolus of 100 mL was administered with a flow of 3 mL/sec. The whole liver was investigated in one breath hold (24 seconds) with a table feed of 10 mm/sec. Images 5 mm thick were reconstructed from the data set. These images were compared with conventional incremental dynamic CT scans (contrast material bolus 100 mL; flow 1 mL/s). Spiral CT showed the whole tumor volume hyperattenuated due to the arterial hypervascularization in all 35 cases. In incremental dynamic CT, all tumors appeared hypoattenuated compared with the liver

  1. The role of spiral CT in pelvic trauma management

    Rapid and accurate assessment of pelvic injury is critical for good patient management. Plain X-ray is often used as a preliminary evaluation of the injury but this may not give adequate diagnosis of the acetabulum fracture, subtle fracture of the pelvic bone and the associated soft tissue injuries. Nowadays, spiral CT has taken an increasing role in the evaluation of pelvic trauma. It gives a rapid assessment of the bone and soft tissue injuries as compared to conventional CT. Besides, 2-D (multiplanar imaging) and 3-D image reconstruction with multiple angle views, provide the maximum information which facilitates detailed pelvic trauma evaluation. Three cases were used to illustrate the role of spiral CT in pelvic trauma management. Copyright (1999) Blackwell Science Pty Ltd

  2. 3D imaging of aortic aneurysma using spiral CT

    The use of 3D reconstructions (3D display technique and maximum intensity projection) in spiral CT for diagnostic evaluation of aortic aneurysma is explained. The data available showing 12 aneurysma of the abdominal and thoracic aorta (10 cases of aneurysma verum, 2 cases of aneurysma dissecans) were selected for verification of the value of 3D images in comparison to transversal displays of the CT. The 3D reconstructions of the spiral CT, other than the projection angiography, give insight into the vessel from various points of view. Such information is helpful for quickly gathering a picture of the volume and contours of a pathological process in the vessel. 3D post-processing of data is advisable if the comparison of tomograms and projection images produces findings of nuclear definition which need clarification prior to surgery. (orig.)

  3. Unenhanced spiral CT in Urolithiasis: indication, performance and interpretation

    Unenhanced spiral computed tomography is now applied in the investigation of patients with acute flank pain to search for suspected urinary tract calculi. Spiral CT can depict urinary calculi more accurately than plain radiographs, sonography or excretory urography, and can be performed using a low dose protocol. Almost all urinary calculi, including calculi composed of uric acid, xanthine and cystine, can be detected. In addition to determining size and location of the stone, unenhanced helical CT can predict its composition. Furthermore, it reveals secondary signs of obstruction, such as dilatation of the renal collecting system and perinephric stranding. In the absence of urolithiasis, CT can frequently detect or exclude other causes of acute flank pain, thus guiding subsequent imaging and the therapeutic management. (orig.)

  4. 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

  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. Multidetector spiral CT arthrography of the shoulder

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

    2008-10-15

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

  7. Multidetector spiral CT arthrography of the shoulder

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

  8. Reduction of patient radiation dose in Spiral CT scan

    To optimize patient radiation dose in Spiral CT scan of dento-maxillo-facial region by measuring the absorbed dose in the phantom and to evaluate reliability of dose estimation methods using CTDI (CT Dose Index, FDA, USA). Spiral CT scanning with 'pitchs' (ratio of table speed to slice thickness per rotation) more than 1 was used for dose measurements. The dose was measured using a human phantom (Alderson Research Laboratories, USA) in the CT scan with a 3rd generation CT scanner of Somatom Plus (Siemens, Germany) for bone imaging. CTDI for this CT scanner were 9.2 mGy/100 mA at the center in an acrylic resin phantom with diameter of 16 cm and 8.5 mGy/100 mA at 1 cm depth from the phantom surface. X-ray tube voltage of 120 kV and tube current of 85 mA was used. Slice thickness was varied from 1 to 3 mm and table speed per rotation was also varied from 1 to 5 mm per rotation. X-Omat-V (Eastman Kodak, USA) films and TLD (Thermo-Luminescent-Dosimetry) dosimeters of the type of MSO-S (Kyokko, Japan) were used in the dosimetry. Patients radiation dose reduced with increasing the pitch of SPIRAL scan. Measured dose was uniformly distributed and well corresponded to the dose calculated using CTDI. However, measured doses on scanning with 1 mm slice thickness were always higher than those with 2 to 5 mm slice thickness. The lowest radiation dose was obtained with scanning with 2 mm slice thickness and table speed of 4 mm per rotation which give the dose of about 4 mGy per one CT examination in the imaged tissues. The highest dose per one CT examination was measured in 'dental CT' for the mandibular region with 1 mm slice thickness and table speed of 1 mm per rotation which gave 12 mGy by film dosimetry and 9 mGy by TLD dosimetry. SPIRAL scan with pitch more than 1 was effective for reduction of patient radiation dose without reducing the image quality. CTDI was also useful to estimate the dose except scans with 1 mm slice thickness. (author)

  9. Low-dose spiral CT: applicability to paediatric chest imaging

    Background. Spiral CT of the chest is an imaging technique with unequivocal indications and proven higher sensitivity and specificity than conventional chest X-rays. However, particularly in children, attempts should be made to reduce radiation exposure to a minimum. Objective. To evaluate whether a low-dose technique in spiral CT scanning results in adequate diagnostic information. Materials and methods. In a prospective study, 27 children (range 3 weeks to 14 years, mean 7 years) underwent a low-dose CT examination of the chest for various indications. The tube energy was 12.5 mAs (n = 5), 25 mAs (n = 17), 50 mAs (n = 3), or 75 mAs (n = 2) per slice. Two radiologists evaluated, in consensus, the CT scans with respect to their diagnostic value and comparison was made with 20 standard-dose chest CT examinations of adults (175 mAs per slice, mean age 56 years) with respect to technical image quality (noise and artefacts). In a second part of the study, dose measurements were carried out by means of exposing thermoluminescent dosimeters attached to a water/air phantom simulating a child's chest. Results. All low-dose CT scans were of diagnostic image quality and no additional studies were necessary. The average image noise was significantly higher than in standard-dose CT examinations (SD 39.5 compared with 12.5 for unenhanced soft tissue, P < 0.01), but did not hinder accurate diagnosis. Artefacts were exclusively due to patient motion. Radiation exposure per slice was approx. 4 mGy at 25 mAs and 34 mGy at 250 mAs, regardless of slice thickness. Conclusions. For all indications in paediatric CT scanning of the chest, low-dose technique provides adequate image quality without loss of diagnostic information. The radiation exposure is approximately 5-20 % of a standard-dose CT. (orig.)

  10. 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

  11. Synchronized control of spiral CT scan for security inspection device

    In security inspection system of spiral CT, the synchronization between removing and rotating, and the scan synchronization between rotating and sampling influence quality of image reconstruction, so it is difficulty and important that how to realize synchronized scan. According to the controlling demand of multi-slice Spiral CT, the method to realize synchronized scan is given. a synchronized control system is designed, in which we use a industrial PC as the control computer, use magnetic grids as position detectors, use alternating current servo motor and roller motor as drivers respectively drive moving axis and rotating axis. This method can solve the problem of synchronized scan, and has a feasibility and value of use. (authors)

  12. Spiral CT in the diagnosis of acute pulmonary embolism

    Hartmann, I.J.C.; Prokop, M. [Univ. Medical Center Utrecht, Utrecht (Netherlands)

    2002-07-01

    The traditional approach in patients with clinically suspected pulmonary embolism includes ventilation-perfusion (V/Q) scintigraphy as the first step. This relatively fast and noninvasive technique allows diagnosis or exclusion of pulmonary embolism in a considerable proportion of patients. However, depending on the patient group and evaluation criteria, the results of the V/Q lung scan are nondiagnostic in 40 to 70% of cases. Further testing is needed because pulmonary embolism will be present in only about a quarter of these patients. In order to find a non-invasive strategy for the diagnostic work-up of PE, several promising developments have been made, e.g. D-dimer analysis and spiral CT angiography. Both techniques are fast, noninvasive, and easy to perform and are now conquering the medical world. In this overview we will focus on Spiral CT: what is its role now and what might be expected in the near future? (orig.)

  13. Spiral CT in the evaluation of the neck

    This paper evaluates prospectively the clinical utility of spiral CT when studying lesions of the neck. Twenty-one patients with suspected neck lesions were evaluated by using spiral studies in 18 intravenous contrast material was administered with an automatic power injector. Patients performed a puffed-cheek maneuver during the studies and were instructed not to swallow. Two readers evaluated the studies for soft-tissue detail, vascular opacification, pharyngeal distention, and swallowing-respiratory artifact. Scores of 1(poor) to 3 (excellent) were assigned to each examination in each category. Scanning times ranged from 24 to 36 seconds. Though the image quality was slightly less than that obtained with conventional CT techniques, the soft-tissue detail scores averaged 2.7. The rapid scanning times minimized respiratory-swallowing artifacts permitted pharyngeal distention, optimizing evaluation of the valleculae and pyriform sinuses; and allowed adequate vascular opacification by using contrast material volumes of 50-100mL

  14. Spiral CT in the diagnosis of acute pulmonary embolism

    The traditional approach in patients with clinically suspected pulmonary embolism includes ventilation-perfusion (V/Q) scintigraphy as the first step. This relatively fast and noninvasive technique allows diagnosis or exclusion of pulmonary embolism in a considerable proportion of patients. However, depending on the patient group and evaluation criteria, the results of the V/Q lung scan are nondiagnostic in 40 to 70% of cases. Further testing is needed because pulmonary embolism will be present in only about a quarter of these patients. In order to find a non-invasive strategy for the diagnostic work-up of PE, several promising developments have been made, e.g. D-dimer analysis and spiral CT angiography. Both techniques are fast, noninvasive, and easy to perform and are now conquering the medical world. In this overview we will focus on Spiral CT: what is its role now and what might be expected in the near future? (orig.)

  15. 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.

  16. Low-dose spiral CT in pediatric diagnostic evaluation of the chest; Niedrigdosis-Spiral-CT in der paediatrischen Thoraxbildgebung

    Rogalla, P.; Stoever, B.; Scheer, I.; Juran, R.; Hamm, B. [Radiologie der Charite der Humboldt-Univ. zu Berlin (Germany); Gaedicke, G. [Paediatrie der Charite, Humboldt-Univ. zu Berlin (Germany)

    1997-12-01

    The conclusion drawn by the authors is that it should be possible to reduce the radiation dose in pediatric CT imaging of the chest by a factor of at least 3, as compared to normal CT imaging of adult patients. However, there is no rule of thumb to be given as to what tube amperes might be best for low-dose CT. The authors achieved suitable results applying the spiral scanning technique and between 25 mA and 75 mA for examination of children. (orig./CB) [Deutsch] Zusammenfassend wird fuer moeglich gehalten, die Strahlendosis bei der paediatrischen Thorax-CT gegenueber der normalen Thorax-CT bei Erwachsenen um einen Faktor von mindestens 3 zu reduzieren. Allerdings gibt es keine Regel dafuer, welche Roehrenstromeinstellung fuer Niedrigdosis-CT die Beste ist. Wir sind zu dem Ergebnis gekommen, dass bei Einsatz des Spiral-Scanning-Verfahrens 25 mA bis 75 mA zur Untersuchung der Kinderthorax ausreichen. (orig.)

  17. 3D Reconstruction in Spiral Multislice CT Scans

    M. Ghafouri

    2005-08-01

    Full Text Available Introduction & Background: The rapid development of spiral (helical computed tomography (CT has resulted in exciting new applications for CT. One of these applications, three-dimensional (3D CT with volume ren-dering, is now a major area of clinical and academic interest. One of the greatest advantages of spiral CT with 3D volume rendering is that it provides all the necessary information in a single radiologic study (and there-fore at the lowest possible price in cases that previously required two or more studies. Three-dimensional vol-ume rendering generates clinically accurate and immediately available images from the full CT data set with-out extensive editing. It allows the radiologist and clinician to address specific questions concerning patient care by interactively exploring different aspects of the data set. Three-dimensional images integrate a series of axial CT sections into a form that is often easier to interpret than the sections themselves and can be made to appear similar to other more familiar images such as catheter angiograms. The data are organized into a 3D matrix of volume elements (voxels. The screen of the computer monitor is a 2D-surface composed of discrete picture elements (pixels. Presenting what is stored in memory (ie, floating within the monitor on a 2D-screen is a challenge, but it is the very problem that 3D reconstruc-tion software has creatively solved. Voxel selection is usually accomplished by projecting lines (rays through the data set that correspond to the pixel matrix of the desired 2D image. Differences in the images produced with various 3D rendering techniques are the result of variations in how voxels are selected and weighted. In this article, I compare 3D volume rendering of spiral CT data with other rendering techniques (shaded surface display, maximum intensity projection and present a brief history of 3D volume rendering and discuss the im-plementation of this promising technology in terms of

  18. Electron beam CT versus 16-slice spiral CT: how accurately can we measure coronary artery calcium volume?

    The purpose of this study was to investigate how accurately CAC volume we can be measured using electron beam computed tomography (CT) and 16-slice spiral CT. CAC models with known volume attached to a cardiac phantom were scanned. The error of measurement, variability between measured and real volumes, and inter-scan measurement variability were obtained. For spiral CT, seven different parameters were included: (1) slice thickness (0.625 mm, 1.25 mm and 2.5 mm), (2) retrospective spiral electrocardiograph (ECG)-gated or prospective axial ECG-triggering, (3) overlapping or non-overlapping. The error of measurement was 15% on electron beam CT and 8-20% on spiral CT. CAC volumes were underestimated in 92% and overestimated in 8% of the electron beam CT scans. Volumes were underestimated in 79%, correct in 5% and overestimated in 16% of the spiral CT scans. The best measurement and the least variability was observed on 0.625-mm retrospective spiral ECG-gated CT (error of 8%), a significant result (t-test: P<0.01) when compared with electron beam CT. CAC volume measurement on CT scanners may be significantly different and often underestimates the real volume of CAC. For precise evaluation of CAC volume, thin-slice retrospective spiral ECG-gated scan using a spiral CT scanner is desirable. (orig.)

  19. Acute cholecystitis: two-phase spiral CT finding

    Oh, Eung Young; Yoon, Myung Hwan; Yang, Dal Mo; Chun Seok; Bae, Jun Gi; Kim, Hak Soo; Kim, Hyung Sik [Chungang Ghil Hospital, Incheon (Korea, Republic of)

    1998-07-01

    To describe the two-phase spiral CT findings of acute cholecystitis. Materials and Methods : CT scans of nine patients with surgically-proven acute cholecystitis were retrospectively reviewed for wall thickening, enhancement pattern of the wall, attenuation of the liver adjacent to the gallbladder, gallstones,gallbladder distension, gas collection within the gallbladder, pericholecystic fluid and infiltration of pericholecystic fat. Results : In all cases, wall thickening of the gallbladder was seen, though this was more distinct on delayed images, Using high-low-high attenuation, one layer was seen in five cases, nd three layers in four. On arterial images, eight cases showed transient focal increased attenuation of the liver adjacent to the gall bladder;four of these showed curvilinear attenuation and four showed subsegmental attenuation. One case showed curvilinear decreased attenuation between increased attenuation of the liver and the gallbladder, and during surgery, severe adhesion between the liver and gallbladder was confirmed. Additional CT findings were infiltration of pericholecystic fat (n=9), gallstones (n=7), gallbladder distension (n=6), pericholecystic fluid(n=3), and gas collection within the gallbladder (n=2). Conclusion : In patients with acute cholecystitis,two-phase spiral CT revealed wall thickening in one or three layers ; on delayed images this was more distinct. In many cases, arterial images showed transient focal increased attenuation of the liver adjacent to the gallbladder.

  20. Spiral CT features of abdomen after whipple's operation

    To assess the CT features of postoperative anatomical changes, surgical complications, and patterns of tumor recurrence after Whipple's operation. 42 spiral CT scans of 31 patients who had undergone Whipple's operation were retrospectively reviewed. Postoperative diagnoses were distal CBD cancer in 13 patients, cancer of the ampulla of Vater in ten, cancer of the head of the pancreas in seven, and microcystic cystadenocarcinoma of the pancreas in one. Time intervals between surgery and CT ranged from 1 week to 5 years. CT features of postoperative anastomotic changes, surgical complications, and patterns of tumor recurrence were analyzed. Gastro- or duodeno-jejunal anastomosis was seen in 32 CT scans(74%), pancreaticojejunostomy in 27(64%), and choledochojejunostomy in 24(57%). Pneumobilia was seen in ten patients(34%). Abnormal fluid collections in the peripancreatic and perihepatic space were demonstrated in two patients who underwent CT scans within 3 weeks after operation. Other complications included wound abscess(n=2), and portal vein occlusion(n=1). The most common site of metastasis was the lymph node(n=8)(retroperitoneal:n=5; mesentery root:n=4; and celiac:n=2), followed by the liver(n=6), peritoneum(n=3), adrenal gland(n=2), and afferent loop(n=1). In three cases, there was local recurrence in the pancreatic bed. To reduce possible diagnostic errors during CT interpretation, a Knowledge of normal postoperative anatomy, common complications, and patterns of disease recurrence following Whipple's operation is important

  1. Intracranial aneurysms: evaluation in 200 patients with spiral CT angiography

    The goal of this study was to assess the usefulness of spiral CT angiography (CTA) with three- dimensional reconstructions in defining intracranial aneurysms, particularly around the Circle of Willis. Two hundred consecutive patients with angiographic and/or surgical correlation were studied between 1993 and 1998, with CTA performed on a GE HiSpeed unit and Windows workstation. The following clinical situations were evaluated: conventional CT suspicion of an aneurysm; follow-up of treated aneurysm remnants or of untreated aneurysms; subarachnoid haemorrhage (SAH) and negative angiography; family or past aneurysm history; and for improved definition of aneurysm anatomy. Spiral CTA detected 140 of 144 aneurysms, and an overall sensitivity of 97%, including 30 of 32 aneurysms 3 mm or less in size. In 38 patients with SAH and negative angiography, CTA found six of the seven aneurysms finally diagnosed. There was no significant artefact in 17 of 23 patients (74%) with clips. The specificity of CTA was 86% with 8 false-positive cases. Spiral CTA is very useful in demonstrating intracranial aneurysms. (orig.)

  2. 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.

  3. Radiation exposure with spiral CT of the paranasal sinuses; Strahlenexposition bei der Spiral-CT der Nasennebenhoehlen

    Dammann, F.; Momino-Traserra, E.; Remy, C.; Claussen, C.D. [Radiologische Universitaetsklinik Tuebingen (Germany). Abt. fuer Radiologische Diagnostik; Pereira, P.L.; Baumann, I.; Koitschev, A. [Universitaetsklinik Tuebingen (Germany). Klinik fuer Hals-Nasen-Ohrenheilkunde

    2000-03-01

    Purpose: Determination of the radiation doses in spiral CT of the paranasal sinuses using a variety of mAs values and scan protocols. Material and methods: CT examinations of the paranasal sinuses were performed using an Alderson-Rando phantom. Radiation dose was determined by LiF-TLD at the level of high risk organs in the head and neck region for combinations of different scan parameters (2/3, 3/3, 3/4 mm) and decreasing charges (200, 150, 100, 50, 25 mAs) on a spiral CT. Additional measurements were performed on three other CT scanners using the 2/3 mm protocol at 50 mAs, and a single slice technique (5/5 mm) on one scanner. Results: The lowest dose values found were 1.88 mGy for the eye lenses, 1.35 mGy for the parotid gland, 0.03 mGy for the thyroid gland and 0.1 mGy for the medulla oblongata using 2 mm collimation and 3 mm table feed at 25 mAs. Maximal dose values resulted using the 3/3 mm protocol at 200 mAs (31.00 mGy for the eye lense, 0.65 mGy for the thyroid gland). There were no significant differences found between the different CT scanners. Conclusions: Using up-to-date CT scanners, radiation exposure may be reduced by a factor of 15-20 compared to that of conventional CT technique. Thus, the exposure of the eye lens comes to only a thousandth of the value supposedly inducing a cataract, as published by the ICRP. (orig.) [German] Ziel: Systematische Erfassung der Strahlenexposition bei der Spiral-CT der Nasennebenhoehlen bei unterschiedlichen Dosen und Scanprotokollen. Material und Methoden: Am Alderson-Rando-Phantom wurden die Dosen an Risikoorganen im Kopf-Halsbereich mittels LiF-TLD-Sonden fuer Kombinationen aus unterschiedlichen Scanparametern (2/3, 3/3, 3/4 mm) und absteigender Ladung (200, 150, 100, 50, 25 mAs) an einem Spiral-CT gemessen. Zusaetzlich wurden Messungen an drei weiteren CT-Geraeten mit dem 2/3-Protokoll bei 50 mAs sowie an einem dieser Geraete im Einzelschicht-Modus mit 5/5 mm durchgefuehrt. Ergebnisse: Die niedrigsten Dosen

  4. Low-dose spiral CT: applicability to paediatric chest imaging

    Rogalla, P.; Stoever, B.; Scheer, I.; Juran, R.; Hamm, B. (Department of Diagnostic and Interventional Radiology, Humboldt-Univ. Berlin (Germany)); Gaedicke, G. (Department of Pediatrics, Humboldt-Univ., Berlin (Germany))

    1999-08-01

    Background. Spiral CT of the chest is an imaging technique with unequivocal indications and proven higher sensitivity and specificity than conventional chest X-rays. However, particularly in children, attempts should be made to reduce radiation exposure to a minimum. Objective. To evaluate whether a low-dose technique in spiral CT scanning results in adequate diagnostic information. Materials and methods. In a prospective study, 27 children (range 3 weeks to 14 years, mean 7 years) underwent a low-dose CT examination of the chest for various indications. The tube energy was 12.5 mAs (n = 5), 25 mAs (n = 17), 50 mAs (n = 3), or 75 mAs (n = 2) per slice. Two radiologists evaluated, in consensus, the CT scans with respect to their diagnostic value and comparison was made with 20 standard-dose chest CT examinations of adults (175 mAs per slice, mean age 56 years) with respect to technical image quality (noise and artefacts). In a second part of the study, dose measurements were carried out by means of exposing thermoluminescent dosimeters attached to a water/air phantom simulating a child's chest. Results. All low-dose CT scans were of diagnostic image quality and no additional studies were necessary. The average image noise was significantly higher than in standard-dose CT examinations (SD 39.5 compared with 12.5 for unenhanced soft tissue, P < 0.01), but did not hinder accurate diagnosis. Artefacts were exclusively due to patient motion. Radiation exposure per slice was approx. 4 mGy at 25 mAs and 34 mGy at 250 mAs, regardless of slice thickness. Conclusions. For all indications in paediatric CT scanning of the chest, low-dose technique provides adequate image quality without loss of diagnostic information. The radiation exposure is approximately 5-20 % of a standard-dose CT. (orig.) With 3 figs., 1 tab., 17 refs.

  5. Abdominal spiral CT in children: which radiation exposure is required?

    We decided to test to what extent dose reduction is possible in abdominal spiral computed tomography (CT) in young children without loss of anatomic diagnostic information. A retrospective study was performed of 30 abdominal CT examinations of children aged 3 months to 7 years. These were divided into two groups: group A with reduced radiation exposure (tube current 50 mA, CT dose index CTDIFDA ≤0.83 mGy) and group B with standard radiation exposure (tube current ≥100 mA, CTDIFDA ≥1.66 mGy). Image quality was assessed using a four-part scale ('excellent', 'good', 'sufficient', 'poor') on visual image impression and visibility of 32 anatomical details. Five experienced radiologists read the CT scans independently who were blinded to the examination parameters. Differences in ranked data were evaluated with Wilcoxon's rank sum test. No difference between groups A and B was observed in visual image impression. Detail visibility was significantly lower in group A, but the differences were limited to right upper quadrant structures (portal vein, common bile duct, pancreatic head, adrenals) and to arterial branches. Significant differences in visibility rated as 'poor' were only found for the hepatic, splenic and renal arteries; all other structures showed no difference between groups A and B. A protocol with reduced radiation exposure (50 mA, CTDIFDA ≤0.83 mGy) allowed the demonstration of most anatomic structures in abdominal spiral CT in young children. For the precise demonstration of small details (e.g. structures of the right upper quadrant), a protocol with standard radiation exposure (≥100 mAs) was superior. (orig.)

  6. Spiral CT findings of peliosis hepatis : a case report

    Kim, Young Hoon; Han, Joon Koo; Choi, Byung Ihn; Kim, Yong Il; Yeon, Kyung Mo [Seoul National Univ. College of Medicine, Seoul (Korea, Republic of)

    1997-03-01

    Peliosis hepatis is a rare disease, resulting in blood filled spaces in the hepatic parenchyma. The authors report a case of peliosis hepatis associated with cholangiocarcinoma of the liver, and include a review of the literature. A 56-year-old man presented with febrile sensation and abdominal distention. Spiral CT showed an irregularly marginated mass, 4cm in size and with peripheral enhancement, in the left lobe of the liver, which was enlarged;its right hepatic lobe revealed inhomogeneous enhancement in portal dominant phase and homogeneous enhancement in the equilibrium phase. Pathologic reports revealed adenocarcinoma in the left lobe of the liver and peliosis hepatis in the right lobe.

  7. 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.)

  8. 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.)

  9. Demonstration of chronic recurrent pulmonary emboli with spiral CT

    Chronic recurrent pulmonary emboli may lead, in rare cases, to progressive pulmonary arterial hypertension which cannot be treated medically. These patients may be helped by bilateral pulmonary thrombenarterectomy. The value of spiral CT in the diagnosis of this condition was demonstrated in 31 patients. In 12 patients, thrombi could be shown to be cause of the pulmonary arterial hypertension. Indirect criteria were vascular occlusions, changes in calibre and mural irregularities which were shown in varying degrees in all patients. In 22 of 31 patients there was non-homogeneity of perfusion with greater opacification of the perfused lung parenchyma. In 11 patients scars related to pleural surfaces were seen. Typical changes of right heart insufficiency (cardiomegaly, widened central pulmonary arteries) were shown in all patients by CT. (orig.)

  10. Spiral CT in gastric carcinoma: Comparison with barium study,fiberoptic gastroscopy and histopathology

    Feng Chen; Yi-Cheng Ni; Kai-Er Zheng; Sheng-Hong Ju; Jun Sun; Xi-Long Ou; Man-Hua Xu; Hao Zhang; Guy Marchal

    2003-01-01

    AIM: To evaluate spiral computed tomography (CT) including virtual gastroscopy for diagnosis of gastric carcinoma in comparison with upper gastrointestinal series (UGI),fiberoptic gastroscopy (FG) and histopathology.METHODS: Sixty patients with histologically proven gastric carcinoma (54 advanced and 6 early) were included in this study. The results of spiral CT were compared with those of UGI and FG. Two observers blindly evaluated images of spiral CT and UGI and video recording of FG with consensus in terms of diagnostic confidence with a five-point scale.Sensitivities of lesion detection, Borrmann′s classification of spiral CT, UGI and FG, as well as the accuracy of TNM staging of spiral CT were determined by comparing them to surgical and histological findings.RESULTS: The lesion detection rate was 98 % (59/60),95 % (57/60) and 98 % (59/60) for spiral CT, UGI and FG,respectively. There were no statistical differences in the detection sensitivity among the three techniques (P>0.05).For the sensitivity in Borrmann′s classification, spiral CT was higher than that of UGI (P=0.025) and similar to that of FG (P>0.05). The accuracy of spiral CT in staging the gastric carcinoma was 76.7 %. Six cases of early gastric carcinoma were all detected by spiral CT as well as FG.CONCLUSION: Spiral CT is equivalent to UGI and FG in the detection of gastric carcinoma, and superior to UGI but similar to FG in the Borrmann′s classification of advanced gastric carcinoma. Spiral CT is more valuable than FG in the staging of gastric carcinoma.

  11. 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)

  12. Spiral CT features of nonfunctioning endocrine tumors of the pancreas

    Objective: To understand the CT features of nonfunctioning endocrine tumors (NFETs) of the pancreas by enhanced dual-phase spiral CT. Methods: Eighteen surgically and pathologically confirmed NFETs of the pancreas were studied with retrospective analysis. The spiral CT findings were investigated by using pre-contrast and contrast scanning (including arterial and portal venous phase) with 10 mm thickness and 1.0 pitch. The contrast-enhanced study started in 30 s and 70 s after initiation of injection of the contrast medium with a volume of 90 ml at the rate of 3 ml/s. Results: The average size of the tumor was 5.3 cm x 5. 9 cm x 6. 2 cm. The tumor localized in the pancreatic head in 9 cases, in the pancreatic neck in 4, in the pancreatic body-tail junction in 3, and in the pancreatic tail in 2. On pre-contrast imaging, the tumors showed mild hypodensity in 7 cases, hypodensity in 3, cystic density in 2, and isodensity in 6, respectively. Among all the lesions 4 tumors exhibited calcification. Moderate to marked enhancement of the lesion accounted for 72.2% (13/ 18). There were 5 tumors with homogenous enhancement, 5 tumors with heterogenous enhancement, and 3 tumors with ring enhancement on the arterial phase scanning. Meanwhile, of the 9 cases with pancreatic head tumor, there was only one case with mild dilation of the common bile duct, and mild dilated pancreatic duct was seen in 3 cases and mild atrophy of the pancreas in 1 case. Peripancreatic vessels were invaded in 5 cases. Conclusion: NFETs of the pancreas presented with moderate to marked enhancement during arterial phase scanning in this study. Meanwhile, the tumor was less likely to invade the common bile duct, pancreatic duct, and peripancreatic vessels as well

  13. Clinical application of low-dose spiral CT for orthodontics

    Objective: To determine the effect of reducing the value of mA or kV on the image quality and the radiation dose of the patients undergoing low-dose spiral CT for orthodontics. Methods: Thirty patients were divided into three groups, each group has 10 patients. They were group 1 (80 kV and 200 mA), group 2 (120 kV and 80 mA), group 3 (120 kV and 200 mA) The volume CT dose index (CTDI) was recorded and the average dose-length produce (DLP) was calculated in three groups,respectively. Image quality of three groups were compared and scored by two radiologists, and the results were statistically analysed. Results: The CTDI and DLP of 80 kV group (group 2) were 8.7 mGy and (36.80 ± 3.60) mGy · cm, respectively, those of 80 mA group (group 3) were 19.6 mGy and (82.14 ± 7.18) mGy · cm, respectively, and those of conventional-dose group (group 1) were 19.6 mGy and (82.14 ± 7.18) mGy · cm, respectively. There was no significant difference among three groups in diagnostic image quality. Conclusions: Low-dose spiral CT for orthodontics, especially the low-kV scan, may decrease the radiation exposure and guarantee the image quality. (authors)

  14. Single-breathhold spiral volumetric CT of the hepatobiliary system

    Interscan respiration prolongs contrast enhancement studies beyond the vascular phase and makes anatomically contiguous scanning of the upper abdomen difficult. The authors intended to scan complete subvolumes within the hepatobiliary system during a single breathhold. A commercial CT scanner allowing up to 12 continuous 1-sec rotations (5--10 mm collimation, 170--250 mAs per rotation) was modified by mounting a movable table on top of the regular table. Instead of measuring one anatomical level dynamically, the authors synchronized data acquisition with longitudinal patient movement (5--10 mm/sec). Dedicated image reconstruction corrected for the helical scanning geometry. Twenty patients with focal liver or biliary pathology were studied. In all patients, spiral volumetric computed tomography (SVCT) demonstrated portal veins, dilated bile ducts, major arteries, and both intrahepatic and extrahepatic mass lesions continuously. Where indicated, reformatting was performed and judged superior to reformatting based on standard single sections

  15. Non-invasive coronary angiography with multislice spiral CT

    The short imaging time of 1/4 second, renders the new generation of multiple-slice spiral CT devices with ECG gating enables the investigation of the heart without disturbing motion artefacts. With this method, calcifications of the coronary arteries can be detected or excluded. Certain amounts of coronary 'chalk' in asymptomatic patients with risk factors point to coronary artery disease and thus a need to modulate the risk factors. With the aid of intravenous injection of contrast medium during the examination, non-calcified plaques in the coronary arteries can also be visualized. A limiting factor is that the patient's heart rate should not exceed 60 beats per minute. Indications for this examination are visualization of coronary vessels with the aim of excluding coronary artery disease, pre-operative planning and monitoring of bypass vessels, and non-invasive follow-up after PTCA and stenting. (orig.)

  16. Helical CT defecography; La defecografia con Tomografia Computerizzata spirale

    Ferrando, R.; Fiorini, G.; Beghello, A.; Cicio, G.R.; Derchi, L.E.; Consigliere, M.; Resasco, M. [Genua Univ., Genua (Italy). Ist. di Radiologia, Cattedra R; Tornago, S. [Genua Univ. Genua (Italy). 2 Clinica Ortopedica

    1999-11-01

    The purpose of this work is to investigate the possible role of Helical CT defecography in pelvic floor disorders by comparing the results of the investigations with those of conventional defecography. The series analyzed consisted of 90 patients, namely 62 women and 28 men, ranging in age 24-82 years. They were all submitted to conventional defecography, and 18 questionable cases were also studied with Helical CT defecography. The conventional examination was performed during the 4 standard phases of resting, squeezing, Valsalva and straining; it is used a remote-control unit. The parameters for Helical CT defecography were: 5 mm beam collimation, pitch 2, 120 KV, 250 m As and 18-20 degrees gantry inclination to acquire coronal images of the pelvic floor. The rectal ampulla was distended with a bolus of 300 mL nonionic iodinated contrast agent (dilution: 3g/cc). The patient wore a napkin and was seated on the table, except for those who could not hold the position and were thus examined supine. Twenty-second helical scans were performed at rest and during evacuation; multiplanar reconstructions were obtained especially on the sagittal plane for comparison with conventional defecographic images. Coronal Helical CT defecography images permitted to map the perineal floor muscles, while sagittal reconstructions provided information on the ampulla and the levator ani. To conclude, Helical CT defecography performed well in study of pelvic floor disorders and can follow conventional defecography especially in questionable cases. [Italian] Scopo di questo lavoro e' ricercare un ruolo per la defeco-TC con apparecchiatura elicoidale nello studio delle malattie del pavimento pelvico confrontandola con i risultati consolidati della defecografia tradizionale. Si sono visionati 90 pazienti, 62 femmine e 28 maschi, con eta' compresa tra 24 e 82 anni, con defecografia tradizionale; di questi, 18 casi con diagnosi dubbia sono stati studiati anche con defeco-TC spirale

  17. 永存三叉动脉的多层螺旋CT诊断%Multislice Spiral CT Diagnosis of Persistent Trigeminal Artery

    陈德强; 张艳春

    2012-01-01

    目的 探讨多层螺旋CT血管成像(CTA)在诊断永存三叉动脉(PTA)中的价值.资料与方法 回顾性分析2546例行头颅64层螺旋CTA检查者中的10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 (1)PTA的发生率为0.39%( 10/2546),其中1例位于右侧,9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8例,中央型2例;按Saltzman分型显示PTA后循环供血情况:Ⅰ型7例,Ⅱ型1例,Ⅲ型2例.(3)吻合点近端的基底动脉及双侧椎动脉发育不良7例.结论 64层CTA能清晰、准确地显示PTA的走行及后循环供血情况.%Objective To assess the value of multislice spiral CT angiography in the diagnosis of persistent trigeminal artery. Materials and Methods The imaging data of 10 patients with persistent trigeminal artery in 2546 patients who received 64 slice CTA of craniocervical arteries were analyzed retrospectively. The incidence,origin,running,and blood supply from posterior circulation of persistent trigeminal artery, and its complicated other vascular malformations were analyzed. Results (1 )The incidence of persistent trigeminal artery was 0. 39% (10/2546). One of them was on the right side and nine were on the left side. (2 ) All the trigeminal arteries originated from the cavernous segment of internal carotid artery. Eight patients were lateral type and two patients were central type. According to Saltzman' s classification about the blood supply from posterior circulation:seven patient was Saltzman type Ⅰ,one was type Ⅱ ,and two were type HI. (3)Seven patients had basilar artery and bilateral vertebral artery hypoplasia at the point of proximal anastomosis. Conclusion 64 slice CTA can clearly display the running route of persistent trigeminal artery and its blood supply of posterior circulation.

  18. Role of spiral CT in the diagnostic work-up of acute and chronic pulmonary embolism

    With the more widespread availability of spiral CT scanners during the last five years spiral CT angiography of the pulmonary arteries has been etablished as an accurate test for acute and chronic pulmonary embolism. It is reliable in the direct visualization of thrombotic material down to the segmental level. In several studies, sensitivity and specificity of 80 to 100% as compared with pulmonary angiography were reported. Compared with scintigraphy and echocardiography, spiral CT more often provides a definite and certain diagnosis. In addition to the direct visualization of the emboli spiral CT shows vessel wall thickening as a sign of older emboli, infarction, pneumonia, pleural effusion. Differential diagnoses are depicted significantly more frequent compared with scintigraphy. In chronic thromboembolic disease spiral CT detects vessel wall alterations even more often than angiography. Additionally, spiral CT demonstrates typical changes due to pulmonary hypertension and right heart failure. Depending on the experience of the investigator and the local conditions, spiral CT is equally well suited for further work-up of indeterminate scintigraphic findings or as a primary screening tool for patients in whom pulmonary embolism is suspected. (orig./MG)

  19. 螺旋CT尿路成像在上尿路梗阻性病变的运用及诊断价值%Application Value of Spiral CT Urography in Diagnosis of Upper Urinary Tract Obstruction Diseases

    李亭; 郭春梅; 王成龙; 李真林; 张洪静; 伍兵

    2011-01-01

    Objective To discuss the utilization and diagnostic value of 64-slice spiral CT urography for upper urinary tract obstruction diseases.Methods We collected the clinical data of 132 patients who were diagnosed with upper urinary tract obstruction by 64-slice spiral CT urography between December 2009 and January 2011.We analyzed the imaging features and compared them with surgical and pathological results.Results Confirmed by surgical and pathological results, 132 patients included 31 cases of urethral stone, 51 cases of congenital variant and malformation, 16 cases of ureteral infection, 29 cases of tumors in urinary tract, 3 cases of extraneous compression,and 2 cases of cysts next to the renal pelvis.CT diagnosis for all cases were basically in line with clinical and pathological results.Conclusion CT urography is an extremely valuable imaging method to diagnose the diseases of urinary system.It can display lesions broadly and reveal their inner and peripheral circumstances clearly, thus can help us determine the reasons and natures of the lesions precisely.%目的 探讨64层螺旋CT尿路造影在上尿路梗阻性病变中的运用及诊断价值.方法 收集2009年12月-2011年1月132例行螺旋CT尿路造影,并确诊为上尿路梗阻病变患者资料,分析其图像特点并与手术及病理结果对比.结果 132例患者经临床及手术病理证实,输尿管结石31例,先天异常及畸形51例,输尿管感染性病变16例,尿路肿瘤29例,外源性压迫3例,肾盂旁囊肿2例;所有患者均显示良好,与临床及病理结果基本吻合.结论 CT尿路造影能多方位清楚显示病变内部及周围情况,可准确的显示、判断尿路梗阻的原因、性质,是一种对泌尿系疾病诊断极有价值的影像学检查方法.

  20. 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

  1. An evaluation of spiral CT scan in diagnosis of unresectable pancreatic carcinoma

    Objective: To investigate the spiral CT findings and diagnostic criteria of unresectable pancreatic carcinoma. Methods: The spiral CT findings of 17 cases of pancreatic carcinoma, confirmed by surgery and histo-pathologic examinations, were retrospectively studied. Factors like peripancreatic vasculars and fat tissue, metastases or adjacent involvement, and the protocol of the scan were carefully evaluated. Results: The CT manifestations of unresectable pancreatic carcinoma included: peripancreatic vascular involvement, metastasis found liver and peritoneum, adjacent organ involvement, distant metastatic lymphadenopathy and invasion of peripancreatic fat plane accompanied with other signs of unresectable lesion revealed in the same evaluation. Conclusion: Spiral CT scan accurately evaluates the range, degree of tumor, metastatic lesions and especially the peripancreatic vascular involvement. Spiral CT scan is a valuable in determining the resectability of pancreatic cancer

  2. 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.

  3. 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

  4. 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

  5. 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

  6. First results of spiral CT angiography in the evaluation of carotid artery stenosis; Erste Ergebnisse der Spiral-CT-Angiographie beim Nachweis von Stenosen der A. carotis

    Link, J. [Klinik fuer Radiologische Diagnostik, Kiel Univ. (Germany); Mueller-Huelsbeck, S. [Klinik fuer Radiologische Diagnostik, Kiel Univ. (Germany); Brossmann, J. [Klinik fuer Radiologische Diagnostik, Kiel Univ. (Germany); Grabener, M. [Klinik fuer Herz- und Gefaesschirgurgie, Kiel Univ. (Germany); Voss, C. [Klinik fuer Herz- und Gefaesschirgurgie, Kiel Univ. (Germany); Heller, M. [Klinik fuer Radiologische Diagnostik, Kiel Univ. (Germany)

    1995-03-01

    To determine the value of spiral CT angiography in Maximum Intensity Projection (MIP)-technique for evaluation of carotid artery stenosis. A comparison of the MIP technique with intraarterial DSA was done in 24 patients with 40 stenoses. Quantification of stenosis was determined according to the NASCET study: mild (0-29%), moderate (30-69%), severe (70-99%) and occlusion (100%). Totally the correlation of spiral CT angiography with DSA was 80% (r=0.93; p=0.0001). In the moderate stenosis group (r=1; p=0.1573), severe stenosis group (r=0.89; p=0.002) and the occlusion group (r=1; p=0.0009) there was a good correlation with DSA. In the mild stenosis group (r=0.55; p=0.0704) correlation of spiral CT angiography with DSA was poor. Spiral CT angiography allows an excellent delineation of calcifications. Tandem lesions and collateral flow cannot be shown with spiral CT angiography. (orig./MG) [Deutsch] Ziel der Studie war es, die Wertigkeit der Spiral-CT-Angiographie in der Maximum-Intensitaets-Projektion (MIP)-Technik bei der Beurteilung von Stenosen der A. carotis interna zu ueberpruefen. Ein Vergleich der MIP-Technik mit der selektiven DSA wurde bei 24 Patienten mit 40 Stenosen der A. carotis interna durchgefuehrt. Die Stenosequantifizierung erfolgte nach den Kriterien der NASCET-Studie: Geringgradig (0-29%); mittelgradig (30-69%); hochgradig (70-99%); Verschluss (100%). Die Spinal-CT-Angiographie korrelierte mit der DSA in 80% (R=0,93; p=0,0001). Bei den mittelgradigen (R=1; p=0,1573) und hochgradigen Stenosen (R=0,89; p=0,002) sowie bei den Verschluessen (R=1; p=0,0009) bestand eine gute Korrelation zur DSA. Bei den geringgradigen Stenosen (R=0,55; p=0,0704) war die Korrelation mit der DSA weniger gut. Kalkplaques lassen sich mit der Spiral-CT-Angiographie hervorragend darstellen. Tandemstenosen und der intrazerebrale Kollateralkreislauf sind mit der Spiral-CT-Angiographie bisher nicht evaluierbar. (orig./MG)

  7. Improvement in printing technique of spiral CT three-dimensional colour image

    Objective: To investigate the printing technique of spiral CT three-dimensional (3D) colour image. Methods: The 3D colour images of 136 patients were printed, with the equipment of Marconi spiral CT, personnel computer, colour ink printer, and network switchboard. Results: All printed images were satisfied by this method. Conclusion: This technique is economic, simple, and useful, and can meet the need for clinical diagnosis and operation. (authors)

  8. Diagnosing pulmonary embolism: establishing and consolidating the role of spiral CT

    Strijen, Marco van

    2007-01-01

    In the Antelope study availability, use and diagnostic accuracy of spiral CT in patients clinically suspected of PE was investigated. This study was divided in two separate phases, starting with a prospective evaluation of available diagnostic techniques part of the diagnostic consensus strategy in The Netherlands in a specifically designed algorithm. Phase I showed that in a direct comparison with the gold standard sensitivity and specificity of spiral CT is too low to endorse its role as a ...

  9. The diagnostic value of 3D spiral CT imaging of cholangiopancreatic ducts on obstructive jaundice

    Linquan Wu; Xiangbao Yin; Qingshan Wang; Bohua Wu; Xiao Li; Huaqun Fu

    2011-01-01

    Objective: Computerized tomography (CT) plays an important role in the diagnosis of diseases of biliary tract. Recently, three dimensions (3D) spiral CT imaging has been used in surgical diseases gradually. This study was designed to evaluate the diagnostic value of 3D spiral CT imaging of cholangiopancreatic ducts on obstructive jaundice. Methods: Thirty patients with obstructive jaundice had received B-mode ultrasonography, CT, percutaneous transhepatic cholangiography (PTC) or endoscopic retrograde cholangiopancreatography (ERCP), and 3D spiral CT imaging of cholangiopancreatic ducts preoperatively. Then the diagnose accordance rate of these examinational methods were compared after operations. Results: The diagnose accordance rate of 3D spiral CT imaging of cholangiopancreatic ducts was higher than those of B-mode ultraso-nography, CT, or single PTC or ERCP, which showed clear images of bile duct tree and pathological changes. As to malignant obstructive jaundice, this examinational technique could clearly display the adjacent relationship between tumor and liver tissue, biliary ducts, blood vessels, and intrahepatic metastases. Conclusion: 3D spiral CT imaging of cholangiopancreatic ducts has significant value for obstructive diseases of biliary ducts, which provides effective evidence for the feasibility of tumor-resection and surgical options.

  10. The value of spiral CT scan on fracture of ankle joint and tarsal bones

    Objective: To study the value of spiral CT scan on the fracture of ankle joint and tarsal bones. Methods: 43 cases with the fracture of ankle joint and tarsal bones were collected and analyzed. All the cases were examined by plain film radiography and spiral CT thin slice scan. Multi-planar reformation (MPR), surface shaded display (SSD) and other techniques of image post-processing were performed in 35 cases of them. Results: Spiral CT scan could demonstrate more fractures than plain film radiography in 28 cases(65.1%). There are 15 cases (34.9%) which are normal in plain film radiography but abnormal in Spiral CT scan. Spiral CT could demonstrate the different length, width, direction and number of linear low density shadow. SSD and MPR were performed again in the cases with avulsion fracture and fragmental fracture to demonstrate the fracture direction and the shape, size and location of fragments more clearly. Conclusion: Spiral CT thin slice scan with image post-processing techniques can play an important role in fracture of ankle joint and tarsal bones. (authors)

  11. Enteroelysis and spiral CT examination in diagnosis and evaluation of small bowel Crohn's disease

    Introduction: During the last few decades introducing many of new radiologic methods, diagnostic conditions and facilities of Crohn's disease has became markedly improved. Appropriate using of these techniques definitely modifies the management of patients with known or suspected Crohn's disease serving reliable information about extent, severity and possible complications of disease. Enteroclysis and Computed tomography are the two major and basic methods to disclose or confirm diagnosis of Crohn's disease, obtain appropriate inforination about disease either with mucosal, transmural or extraintestinal manifestation. Methods and patients: We evaluated 281 patients who were referred in our institution under suspicion of Crohn's disease. Enteroclysis and abdominal spiral CT in all cases were carried out usually within 1 week. The 172 patients underwent abdominal spiral CT as the primary examination to evaluate diagnostic value of spiral CT in this entity, while 109 patients had enteroclysis followed by abdominal CT. In 11 cases we also perforined CT enteroclysis with administration of 0.5% methylcellulose solution thorough nasojejunal tube controlled by electric motor driven contrast pump. Results were compared with final clinical, pathological or surgical data were available. Results: From the 281 patients eventually 74 proved Crohn's disease; sensitivity and specificity of enteroclysis proved to be 96 and 98%, while spiral CT sensitivity and specificity was 94 and 95%, respectively. Enteroclysis was superior to the spiral CT in demonstration of early lesions and functional disorders, while spiral CT proved to be essential in evaluation of transmural and extraintestinal complications. Conclusions: Regarding enteroclysis and spiral CT as complementary methods, they provide excellent results in diagnosis of Crohn's disease

  12. Measurement error of spiral CT volumetry: influence of low dose CT technique

    To examine the possible measurement errors of lung nodule volumetry at the various scan parameters by using a small nodule phantom. We obtained images of a nodule phantom using a spiral CT scanner. The nodule phantom was made of paraffin and urethane and its real volume was known. For the CT scanning experiments, we used three different values for both the pitch of the table feed, i.e. 1:1, 1:15 and 1:2, and the tube current, i.e. 40 mA, 80 mA and 120 mA. All of the images acquired through CT scanning were reconstructed three dimensionally and measured with volumetry software. We tested the correlation between the true volume and the measured volume for each set of parameters using linear regression analysis. For the pitches of table feed of 1:1, 1:1.5 and 1:2, the mean relative errors were 23.3%, 22.8% and 22.6%, respectively. There were perfect correlations among the three sets of measurements (Pearson's coefficient = 1.000, p< 0.001). For the tube currents of 40 mA, 80 mA and 120 mA, the mean relative errors were 22.6%, 22.6% and 22.9%, respectively. There were perfect correlations among them (Pearson's coefficient=1.000, p<0.001). In the measurement of the volume of the lung nodule using spiral CT, the measurement error was not increased in spite of the tube current being decreased or the pitch of table feed being increased

  13. 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

  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. 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.

  16. Measurement of total lung capacity : a comparison of spiral CT and spirometry

    Chung, Kyung Il; Park, Kyung Ju; Lee, Eh Hyung; Yune, Heun Young; Suh, Jung Ho [Ajou Univ. School of Medicine, Suwon (Korea, Republic of); Choe, Kyu Ok; Lim, Tae Hwan [Yonsei Univ. College of Medicine, Seoul (Korea, Republic of); Chung, In Hyuk [Ulsan Univ. College of Medicine, Seoul (Korea, Republic of)

    1996-08-01

    To determine the potential of spiral CT as a functional imaging modality of the lung aside from its proven value in morphological depiction. Spiral CT scan was performed in ten normal female and nine normal male adults (mean age: 39, height: 163 cm, weight: 62 kg ) after single full breath-holding. Three dimensional lung images were reconstructed(minimal threshold value: -1,000HU, maximal threshold values: -150, 250, -350, -450 HU) to obtain total lung volume(TLV) on a histogram. Total lung volume measured by spiral CT was compared with TLV obtained by spirometry. Mean TLV measured by spirometry was 5.62L and TLV measured by CT at maximal threshold values of -150, -250, -350, and -450 HU was 5.53, 5.33, 5.15, and 4.98L, respectively. Mean absolute differences between the modalities of 0.17L(3%), 0.32L(5.6%), 0.48L(8.5%), 0.65L(11.5%) were statistically significant(p<0.001). Linear regression coefficients between the modalities were 0.99, 0.97, 095, and 0.94 and no statistically significant differences in accuracy of threshold levels in the estimation of lung volume(r=0.99, standard error=0.034L in all) were seen. TLV measured by spiral CT closely approximated that measured by spirometry. Spiral CT may be useful as a means of evaluating lung function.

  17. Measurement of total lung capacity : a comparison of spiral CT and spirometry

    To determine the potential of spiral CT as a functional imaging modality of the lung aside from its proven value in morphological depiction. Spiral CT scan was performed in ten normal female and nine normal male adults (mean age: 39, height: 163 cm, weight: 62 kg ) after single full breath-holding. Three dimensional lung images were reconstructed(minimal threshold value: -1,000HU, maximal threshold values: -150, 250, -350, -450 HU) to obtain total lung volume(TLV) on a histogram. Total lung volume measured by spiral CT was compared with TLV obtained by spirometry. Mean TLV measured by spirometry was 5.62L and TLV measured by CT at maximal threshold values of -150, -250, -350, and -450 HU was 5.53, 5.33, 5.15, and 4.98L, respectively. Mean absolute differences between the modalities of 0.17L(3%), 0.32L(5.6%), 0.48L(8.5%), 0.65L(11.5%) were statistically significant(p<0.001). Linear regression coefficients between the modalities were 0.99, 0.97, 095, and 0.94 and no statistically significant differences in accuracy of threshold levels in the estimation of lung volume(r=0.99, standard error=0.034L in all) were seen. TLV measured by spiral CT closely approximated that measured by spirometry. Spiral CT may be useful as a means of evaluating lung function

  18. Comparison between spiral CT and MR imaging in evaluation of focal hepatic masses

    The main aim of this study was to compare spiral CT and MR imaging in the detection and characterization of focal hepatic masses. Seventy-nine patients with 155 focal hepatic masses confirmed pathologically, or radiologically and clinically [hepatocellular carcinoma(HCC) (n=52), hemangioma (n=36), cysts (n=35), metastasis (n=27), intrahepatic cholangiocarcinoma (n=5), underwent two- or three-phase spiral CT, and T1-, T2-weighted, and dynamic contrast-enhanced MR imaging. The detection and characterization of focal hepatic masses by these modalities were evaluated and compared. The detection rates of spiral CT and MR imaging, respectively, were as follows: HCC, 81%(42/52) and 94%(49/52); hemangioma, 75%(27/36) and 100%(36/36); cysts, 80%(28/35) and 100%(35/35); metastasis, 67%(18/27) and 100%(27/27); and intrahepatic cholangiocarcinoma, 100%(5/5) and 100%(5/5). MR imaging was superior to spiral CT in mass detection of HCC, hemangioma, cysts, and metastasis (p < .05). The characterization rates of spiral CT and MR imaging, respectively, were as follows: HCC, 52%(27/52) and 71%(37/52); hemangioma, 67%(24/36) and 100%(36/36); cysts, 63%(22/35) and 100%(35/35); metastasis, 37%(10/27) and 100%(27/27); and intrahepatic cholangiocarcinoma, 40%(2/5) and 80%(4/5). In the mass characterization of HCC, hemangioma, cysts, and metastasis, MR imaging was superior to spiral CT(p < .05). In the detection and characterization of focal hepatic masses, including hepatocellular carcinoma, hemangioma, hepatic cyst and metastasis, MR imaging is superior to spiral CT

  19. Spiral CT scanning plan to generate accurate Fe models of the human femur

    In spiral computed tomography (CT), source rotation, patient translation, and data acquisition are continuously conducted. Settings of the detector collimation and the table increment affect the image quality in terms of spatial and contrast resolution. This study assessed and measured the efficacy of spiral CT in those applications where the accurate reconstruction of bone morphology is critical: custom made prosthesis design or three dimensional modelling of the mechanical behaviour of long bones. Results show that conventional CT grants the highest accuracy. Spiral CT with D=5 mm and P=1,5 in the regions where the morphology is more regular, slightly degrades the image quality but allows to acquire at comparable cost an higher number of images increasing the longitudinal resolution of the acquired data set. (author)

  20. 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)

  1. First results of spiral CT angiography in the evaluation of carotid artery stenosis

    To determine the value of spiral CT angiography in Maximum Intensity Projection (MIP)-technique for evaluation of carotid artery stenosis. A comparison of the MIP technique with intraarterial DSA was done in 24 patients with 40 stenoses. Quantification of stenosis was determined according to the NASCET study: mild (0-29%), moderate (30-69%), severe (70-99%) and occlusion (100%). Totally the correlation of spiral CT angiography with DSA was 80% (r=0.93; p=0.0001). In the moderate stenosis group (r=1; p=0.1573), severe stenosis group (r=0.89; p=0.002) and the occlusion group (r=1; p=0.0009) there was a good correlation with DSA. In the mild stenosis group (r=0.55; p=0.0704) correlation of spiral CT angiography with DSA was poor. Spiral CT angiography allows an excellent delineation of calcifications. Tandem lesions and collateral flow cannot be shown with spiral CT angiography. (orig./MG)

  2. Renal colic: comparison of spiral CT, US and IVU in the detection of ureteral calculi

    Yilmaz, S.; Sindel, T.; Arslan, G.; Oezkaynak, C.; Karaali, K.; Kabaalioglu, A.; Lueleci, E. [Department of Radiology, Akdeniz University Medical Faculty, Arapsuyu, Antalya (Turkey)

    1998-03-01

    The aim of our study was to compare noncontrast spiral CT, US and intravenous urography (IVU) in the evaluation of patients with renal colic for the diagnosis of ureteral calculi. During a period of 17 months, 112 patients with renal colic were examined with spiral CT, US and IVU. Fifteen patients were lost to follow-up and excluded. The remaining 97 patients were defined to be either true positive or negative for ureterolithiasis based on the follow-up data. Sensitivity, specificity, positive and negative predictive value and accuracy of spiral CT, US and IVU were determined, and secondary signs of ureteral stones and other pathologies causing renal colic detected with these modalities were noted. Of 97 patients, 64 were confirmed to have ureteral calculi based on stone recovery or urological interventions. Thirty-three patients were proved not to have ureteral calculi based on failure to recover a stone and diagnoses unrelated to ureterolithiasis. Spiral CT was found to be the best modality for depicting ureteral stones with a sensitivity of 94 % and a specificity of 97 %. For US and IVU, these figures were 19, 97, 52, and 94 %, respectively. Spiral CT is superior to US and IVU in the demonstration of ureteral calculi in patients with renal colic, but because of its high cost, higher radiation dose and high workload, it should be reserved for cases where US and IVU do not show the cause of symptoms. (orig.) With 4 figs., 3 tabs., 12 refs.

  3. Renal colic: comparison of spiral CT, US and IVU in the detection of ureteral calculi

    The aim of our study was to compare noncontrast spiral CT, US and intravenous urography (IVU) in the evaluation of patients with renal colic for the diagnosis of ureteral calculi. During a period of 17 months, 112 patients with renal colic were examined with spiral CT, US and IVU. Fifteen patients were lost to follow-up and excluded. The remaining 97 patients were defined to be either true positive or negative for ureterolithiasis based on the follow-up data. Sensitivity, specificity, positive and negative predictive value and accuracy of spiral CT, US and IVU were determined, and secondary signs of ureteral stones and other pathologies causing renal colic detected with these modalities were noted. Of 97 patients, 64 were confirmed to have ureteral calculi based on stone recovery or urological interventions. Thirty-three patients were proved not to have ureteral calculi based on failure to recover a stone and diagnoses unrelated to ureterolithiasis. Spiral CT was found to be the best modality for depicting ureteral stones with a sensitivity of 94 % and a specificity of 97 %. For US and IVU, these figures were 19, 97, 52, and 94 %, respectively. Spiral CT is superior to US and IVU in the demonstration of ureteral calculi in patients with renal colic, but because of its high cost, higher radiation dose and high workload, it should be reserved for cases where US and IVU do not show the cause of symptoms. (orig.)

  4. MRI with superparamagnetic iron oxide vs. double-spiral CT when identifying malignant liver lesions

    Purpose: The purpose of this study was to evaluate the efficacy of MRI with superparamagnetic iron oxide (SPIO) and double-spiral CT in the detection of liver metastases and hepatocellular carcinoma. Results: SPIO-MRI shows the highest rate of detection and is significantly superior to native MRI and native CT. The highest rate of detection by CT is shown in the portal-venous phase of contrast; nevertheless, the rate is significantly inferior to SPIO-MRI. In general, the native phases of CT and MRI are significantly inferior to the contrast phases of both. SPIO-MRI shows a higher rate of false positive findings. Conclusion: The time-consuming and cost-intensive SPIO-MRI significantly increases the rate of detectability for malignant liver lesions compared with double-spiral CT but it also increases the rate of false positive findings. (orig./AJ)

  5. Hepatic spiral CT in children: scan delay time-enhancement analysis

    Purpose. To compare the effect of different time delays between contrast administration and the start of spiral CT scanning on hepatic enhancement in children. Materials and methods. Forty-five children (2-9 years old, mean 6 years) with no evidence of hepatic disease were examined with spiral CT. Sequential spiral scans through the entire liver were performed following a uniphasic injection of nonionic contrast medium. In group 1 scanning started at 80 % of the contrast injection time, in group 2 scanning started at 100 % of injection time, and in group 3 scanning started at 150 % of injection time. Mean hepatic, aortic, and inferior vena caval enhancement were determined using regions-of-interest measurements. Results. Mean hepatic enhancement was 41.4, 47.0, and 40.6 HU for the 80 %, 100 %, and 150 % injection times, respectively. Enhancement was significantly greater in the 100 % injection time group (p < 0.05). A mean aortocaval difference of greater than 10 HU was present in all examinations. Conclusion. Our results suggest that delaying the initiation of spiral CT scanning until the completion of the contrast injection increases hepatic enhancement in children. These data should help to improve the quality of hepatic spiral CT in pediatric patients. (orig.). With 2 tabs

  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. The diagnosis of intrahepatic cholangiocarcinoma with spiral CT

    Objective: To explore the CT features of intrahepatic cholangiocarcinoma. Methods: CT findings of 37 cases with intrahepatic cholangiocarcinoma proved by pathologically were analyzed retrospectively. Results: Three kinds of enhancement areas could be found, that were non-enhancement area, gradually contrast enhancement area and delayed contrast enhancement area. Two or three enhanced features could be found in one lesion. Conclusion: CT scanning was an important method for intrahepatic cholangiocarcinoma. The CT features could help us give a correct diagnosis. (authors)

  8. 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.

  9. Spiral CT arthrography of the knee: technique and value in the assessment of internal derangement of the knee

    Computed tomography imaging has achieved excellent multiplanar capability and submillimeter spatial resolution due to the development of the spiral acquisition mode and multidetector row technology. Multidetector spiral CT arthrography (CTA) yields valuable information for the assessment of internal derangement of the joints. This article focuses on the value of spiral CTA of the knee in the assessment of the meniscus, anterior cruciate ligament, and hyaline cartilage lesions. Advantages and disadvantages of spiral CTA with respect to MR imaging are presented. (orig.)

  10. Correlation between contrast enhancement of portal vein and spleen size in dual-phase spiral CT

    To evaluate using spiral CT the effect of spleen size on blood flow in the portal venous system and to know the usefulness of this evaluation. Fifty-one patients without evidence on spiral CT scan of abnormality thought to affect portal venous flow presented between December 1994 and June 1995. We measured spleen size and Hounsfield units of portal vein in dual-phase, and calculated the ratio of the unit in the portal phase to that in the arterial phase. Spleen size was measured, using the length of X-axis by that of Z-axis on spiral CT scan. We then measured the correlation between the two values. CT was performed with a Somatom Plus-S scanner(Siemens, Erlangen, Germany). A total dose of 120ml of non-ionic contrast material(Ultravist) was administered at a rate of 3 ml/sec. Arterial and portal phase were obtained after 30 seconds and 60 seconds from the begining of the contrast agent injection. The correlation between spleen size and contrast enhancement of the portal vein was relatively significant(Pearson's correlation coefficient(r)=0.41801). Spleen size significantly affects portal venous flow on spiral CT scan. The evaluation of spleen size and contrast enhancement of the portal vein could be useful in the differential diagnosis of diseases which affect portal venous flow

  11. Functional spiral-CT in post-tumor follow-up of the irradiated larynx; Funktionsspiral-CT in der Nachsorge bestrahlter Kehlkopfkarzinome

    Keitel, T.; Kloeppel, R.; Kamprad, F. [Universitaetsklinikum Leipzig (Germany). Zentrum fuer Radiologie; Meister, E.F. [Universitaetsklinikum Leipzig (Germany). Klinik fuer Hals-Nasen-Ohrenkrankheiten

    1998-02-01

    The importance of spiral-CT is clinically accepted for diagnosing spreading disease and for making a decision about the therapy strategy for head and neck tumors. Its importance for follow-up after radiotherapy was examined in 26 patients with irradiated laryngeal tumors. Using spiral-CT multiple signs of alterations (n=98) can be diagnosed, which are not only important for tumor relapse, but also for assessment. Spiral-CT offers the possibility of achieving various additional information about the larynx that cannot be obtained with laryngoscopy. In follow-up examinations after radiation, laryngoscopy and spiral-CT are recommended as an integrated neck examination using the breath-holding technique (separately reconstructed) and also as functional spiral-CT of the vocal cords in `I`-phonation. (orig.) [Deutsch] Die Spiral-CT hat bei der Ausbreitungsdiagnostik und Therapieentscheidung von Karzinomen des Kopf-Hals-Bereiches einen anerkannt hohen Stellenwert. Ihre Bedeutung fuer die Tumornachsorge wird an 26 Patienten mit alleinig bestrahltem Kehlkopfkarzinom untersucht. Spiralcomputertomographisch koennen zahlreiche Veraenderungen (n=98) aufgezeigt werden, die nicht allein fuer die Rezidivdiagnostik von Interesse sind, sondern zusaetzliche moeglicherweise gutachterlich relevante Informationen liefern, die laryngoskopisch in dieser Sensitivitaet nicht zu erreichen sind. Im Nachsorgemanagement empfiehlt sich neben der Laryngoskopie die Durchfuehrung des Spiral-CT als integrierte Halsuntersuchung in Atemruhelage (separat rekonstruiert) und zusaetzlich als Funktionsspiral-Spiral-CT der Stimmlippen in `I`-Phonation. (orig.)

  12. Diagnosis of pulmonary embolism with spiral CT as a second procedure following scintigraphy

    Strijen, Marco J.L. van; Kieft, Gerard J. [Department of Radiology, Leyenburg Ziekenhuis, Leyweg 275, 2545 CH The Hague (Netherlands); Monye, Wouter de; Bloem, Johan L. [Department of Radiology, Leiden University Medical Center, P.O. Box 9600, 2300 RC Leiden (Netherlands); Pattynama, Peter M.T. [Department of Radiology, Leiden University Medical Center, P.O. Box 9600, 2300 RC Leiden (Netherlands); Department of Radiology, Erasmus University Medical Center Rotterdam, Dr. Molewaterplein 40, 3015 GD Rotterdam (Netherlands); Huisman, Menno V. [Leiden University Medical Center, Dept. of General Internal Medicine, P.O. Box 9600, 2300 RC Leiden (Netherlands); Smith, Sierd J. [Department of Internal Medicine, Leyenburg Hospital, Leyweg 275, 2545 CH The Hague (Netherlands)

    2003-07-01

    Heading Abstract.Our objective was to evaluate, in a routine clinical setting, the role of spiral CT as a second procedure in patients with clinically suspected pulmonary embolism (PE) and abnormal perfusion scan. We prospectively studied the role of spiral CT in 279 patients suspected of PE. All patients started their diagnostic algorithm with chest radiographs and perfusion scintigraphy. Depending on the results of perfusion scintigraphy, patients proceeded to subsequent levels in the algorithm: stop if perfusion scintigraphy was normal; CT and pulmonary angiography if subsegmental perfusion defects were seen; ventilation scintigraphy followed by CT when segmental perfusion defects were seen; and pulmonary angiography in this last group when results of ventilation/perfusion scintigraphy and CT were incongruent. Reference diagnosis was based on normal perfusion scintigraphy, high probability perfusion/ventilation scintigraphy in combination with abnormal CT, or pulmonary angiography. If PE was present, the largest involved branch was noted on pulmonary angiography, or on spiral CT scan in case of a high-probability ventilation/perfusion scan and a positive CT scan. A distinction was made between embolism in a segmental branch or larger, or subsegmental embolism. Two hundred seventy-nine patients had abnormal scintigraphy. In 27 patients spiral CT and/or pulmonary angiography were non-diagnostic and these were excluded for image analysis. Using spiral CT we correctly identified 117 of 135 patients with PE, and 106 of 117 patients without PE. Sensitivity and specificity was therefore 87 and 91%, respectively. Prevalence of PE was 53%. Positive and negative predictive values were, respectively, 91 and 86%. In the high-probability group, sensitivity and specificity increased to 97 and 100%, respectively, with a prevalence of 90%. In the non-high probability-group sensitivity and specificity decreased to 61 and 89%, respectively, with a prevalence of 25%. In a routine

  13. Diagnosis of pulmonary embolism with spiral CT as a second procedure following scintigraphy

    Heading Abstract.Our objective was to evaluate, in a routine clinical setting, the role of spiral CT as a second procedure in patients with clinically suspected pulmonary embolism (PE) and abnormal perfusion scan. We prospectively studied the role of spiral CT in 279 patients suspected of PE. All patients started their diagnostic algorithm with chest radiographs and perfusion scintigraphy. Depending on the results of perfusion scintigraphy, patients proceeded to subsequent levels in the algorithm: stop if perfusion scintigraphy was normal; CT and pulmonary angiography if subsegmental perfusion defects were seen; ventilation scintigraphy followed by CT when segmental perfusion defects were seen; and pulmonary angiography in this last group when results of ventilation/perfusion scintigraphy and CT were incongruent. Reference diagnosis was based on normal perfusion scintigraphy, high probability perfusion/ventilation scintigraphy in combination with abnormal CT, or pulmonary angiography. If PE was present, the largest involved branch was noted on pulmonary angiography, or on spiral CT scan in case of a high-probability ventilation/perfusion scan and a positive CT scan. A distinction was made between embolism in a segmental branch or larger, or subsegmental embolism. Two hundred seventy-nine patients had abnormal scintigraphy. In 27 patients spiral CT and/or pulmonary angiography were non-diagnostic and these were excluded for image analysis. Using spiral CT we correctly identified 117 of 135 patients with PE, and 106 of 117 patients without PE. Sensitivity and specificity was therefore 87 and 91%, respectively. Prevalence of PE was 53%. Positive and negative predictive values were, respectively, 91 and 86%. In the high-probability group, sensitivity and specificity increased to 97 and 100%, respectively, with a prevalence of 90%. In the non-high probability-group sensitivity and specificity decreased to 61 and 89%, respectively, with a prevalence of 25%. In a routine

  14. 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

  15. Invited article: Helical/spiral CT scanning: a pediatric radiology perspective

    Helical/spiral CT technology has several potential benefits for scanning pediatric patients. These benefits include reduced sedation rates, decreased radiation exposure with scanning at extended pitch, improved image quality, and better three-dimensional and reformatted images. This paper reviews the technical and clinical considerations relevant to scanning the pediatric patient and offers suggestions for protocol development. (orig.)

  16. Spiral-CT angiography after intraarterial iliac stent placement

    In a prospective study 32 patients underwent CT-A after stent placement in the iliac arteries. The vascular morphology was analyzed regarding neointimal hyperplasia and calcification pattern. The results were compared with those of clinical findings (walking distance), Doppler ultrasound (ankle-brachial index) and DSA. All 47 stents were visible and patent (100%). One misplacement was identified. A good correlation was found between an improved ankle-brachial index and CT-A (88.5%) and extension of the walking distance and CT-A (92.3%). Concerning location, number and grade of stenoses the results between CT-A and DSA matched in 42.1%. An exact mapping of calcified plaques was possible in all cases. (orig./MG)

  17. 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.)

  18. Low-dose spiral CT in pediatric diagnostic evaluation of the chest

    The conclusion drawn by the authors is that it should be possible to reduce the radiation dose in pediatric CT imaging of the chest by a factor of at least 3, as compared to normal CT imaging of adult patients. However, there is no rule of thumb to be given as to what tube amperes might be best for low-dose CT. The authors achieved suitable results applying the spiral scanning technique and between 25 mA and 75 mA for examination of children. (orig./CB)

  19. 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

  20. 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.

  1. Administration of contrast medium in spiral CT: Results of a consensus conference

    The rapidity of spiral (helical-) computed tomography requires new protocols for i.v. contrast media administration. Flow rate, volume and delay are discussed controversially in the literature. Hence, a consensus meeting was initiated. In this meeting, problem related questions were designed, discussed and answered using a digital vote system. Spiral-CT-technology was found to be the ideal examination technique for thorax, liver, pancreas, kidney and the retroperitoneal space with an overall agreement between 89 and 97%. The exclusive use of nonionic contrast media and power injectors was recommended by 100% of the participants. More than 90% of the contributors did not accept native scans only for examinations of the neck, thorax, liver, pancreas, kidney and the retroperitoneal space. Regarding volume, flow rate, delay and physical CT-parameters the agreement laid between 50 and 100%. The meeting concluded that randomised controlled studies should be performed to evaluate detailed contrast media protocols for helical CT. (orig.)

  2. 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.

  3. Spiral CT during pharmacoangiography with angiotensin II in patients with pancreatic disease. Technique and diagnostic efficacy

    Kuroda, C.; Mihara, N.; Hosomi, N.; Inoue, E.; Fujita, M. [Osaka Medical Center for Cancer and Cardiovascular Diseases (Japan). Dept. of Diagnostic Radiology; Ohigashi, H.; Ishikawa, O. [Osaka Medical Center for Cancer and Cardiovascular Diseases (Japan). Dept. of Surgery; Nakaizumi, A. [Osaka Medical Center for Cancer and Cardiovascular Deseases (Japan). Dept. of Internal Medicine; Ishiguro, S. [Osaka Medical Center for Cancer and Cardiovascular Diseases (Japan). Dept. of Pathology

    1998-03-01

    Purpose: To compare the diagnostic efficacy of pancreatic pharmacoangiographic CT using angiotensin II with conventional angiographic CT. Material and Methods: Eighteen patients with space-occupying pancreatic disease were examined in this study. Pharmacoangiographic CT was performed with a 1-3-{mu}/6-ml solution of angiotensin II injected through a catheter into the celiac artery during spiral CT. Results: In 17 of the 18 (94%) patients, the area of pancreatic parenchymal enhancement was the same or larger at pharmacoangiographic CT than at conventional angiographic CT. The attenuation value of the pancreatic parenchyma was significantly increased at pharmacoangiographic CT (p=0.0010). Although the attenuation value of tumors was also increased on images obtained after the injection of angiotensin II, the tumor-to-pancreas contrast was significantly greater at pharmacoangiographic CT (p=0.0479). The mean differences in attenuation between tumor and pancreas at angiographic CT with and without angiotensin II were respectively 182 HU and 115 HU. Conclusion: Pharmacoangiographic CT with angiotensin II proved superior to conventional angiographic CT in the diagnosis of pancreatic disease. We therefore recommend it as a supplementary technique at the angiographic examination of patients with suspected pancreatic tumor. (orig.).

  4. Epidurography: Comparison with CT-, helical-CT- and MR-Epidurography; Die Epidurographie: Vergleich mit CT-, Spiral-CT- und MR-Epidurographie

    Tomczak, R. [Univ. Ulm, Klinik fuer Radiologie (Germany); Seeling, W. [Univ. Ulm, Klinik fuer Anaesthesiologie (Germany); Rieber, A. [Univ. Ulm, Klinik fuer Radiologie (Germany); Sokiranski, R. [Univ. Ulm, Klinik fuer Radiologie (Germany); Rilinger, N. [Univ. Ulm, Klinik fuer Radiologie (Germany); Brambs, H.J. [Univ. Ulm, Klinik fuer Radiologie (Germany)

    1996-08-01

    liegenden Epiduralkathetern (EK) und drei Probanden nach Anlage eines EK wurden nach Injektion von Gadolinium-DTPA einer MR-Epidurographie, die drei Probanden zusaetzlich einem Doppel-Helix-Spiral-CT nach Injektion von jodhaltigem Kontrastmittel unterzogen. Ergebnisse: 40% der Patienten zeigten ein Schienenstrangphaenomen bedingt durch eine unterschiedlich starke Fuellung des Epiduralraumes mit Kontrastmittel im Bereich der Wirbelboegen und des Zwischenwirbelbogenbereiches, 76% der Patienten zeigten keinen ventralen thorakalen Epiduralraum, 56% eine Aufhellungslinie im a.-p. Bild der Epidurographie, die als Plica mediana dorsalis im CT identifiziert wurde. Die vorbeschriebenen Phaenomene wurden auch bei allen in der Spiral-CT- und MR-Epidurographie untersuchten Personen nachgewiesen. Schlussfolgerung: Die CT-Epidurographie ist geeignet zur Erklaerung von Bildmustern der Epidurographie. (orig.)

  5. 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.

  6. Stellenwert des Nativ-Spiral-CT in der Diagnostik von Ureterkonkrementen

    Rau O

    2006-01-01

    Full Text Available Die differentialdiagnostische Vorgehensweise bei Pat. mit einer Urolithiasis, insbesondere bei Pat. mit nicht schattengebenden Konkrementen im konventionellen Röntgen, ist oftmals schwierig. Wir evaluierten den Einsatz des Nativ-Spiral-CT in dieser Patientengruppe. Die Sensitivität und Spezifität variiert in der Literatur zwischen 80 und 100 %. Zwischen 4/99 und 11/04 führten wir bei 103 Patienten (Pat. mit kolikartigen Flankenschmerzen, aber ohne Steinnachweis im konventionellen Röntgen, ein natives Spiral-CT durch. Zusätzlich verglichen wir mit dem korrespondierenden Ultraschall und der dazugehörigen Urinanalyse. Endpunkte unserer Untersuchung waren einerseits (A der makroskopische Steinnachweis, entweder als spontan abgegangenes Konkrement oder nach interventioneller Bergung des Konkrementes, bzw. (B kein Nachweis eines Konkrementes. Ein Steinnachweis ließ sich bei 55/103 Pat. führen. Bei 41/55 ließ sich mittels Spiral-CT das Konkrement bestätigen. Dies entspricht einer Spezifität von 75 %. 49 der 55 Pat. hatten zusätzlich eine Erythrozyturie und ebenfalls 49/55 zeigten im Ultraschall eine Dilatation des Nierenbeckenkelchsystems. Bei 48 Pat. von 103 wurden keine Konkremente gesichert. Bei 39 Pat. ließ sich in dieser Gruppe im Spiral-CT ebenfalls kein Konkrementnachweis führen, was einer Sensitivität von 82 % entspricht. Falsch positive Ergebnisse bei 9 Pat. ließen sich retrospektiv in der Auswertung der Spiral-CT’s auf Kalzifizierung benachbarter Strukturen zurückführen. Bei 34/48 wurde eine Erythrozyturie und bei 32/48 eine Dilatation des oberen Harntraktes diagnostiziert. Retrospektiv wurden diese Symptome auf eine infektiöse Mitbeteiligung des Retroperitonealraumes zurückgeführt. Zusätzlich ließ sich eine Raumforderung der Leber, eine Raumforderung im Bereich des proximalen Femur und drei Kolontumore sichern. Unsere Serie von Spiral-CT’s bei Pat. ohne Konkrementnachweis im konventionellen Röntgen zeigte eine

  7. Spiral-CT angiography after intraarterial iliac stent placement; Spiral-CT-Angiographie nach arterieller iliakaler Stentapplikation

    Freund, M. [Kiel Univ. (Germany). Klinik fuer Radiologische Diagnostik; Palmie, S. [Kiel Univ. (Germany). Klinik fuer Radiologische Diagnostik; Wesner, F. [Kiel Univ. (Germany). Klinik fuer Radiologische Diagnostik; Heller, M. [Kiel Univ. (Germany). Klinik fuer Radiologische Diagnostik

    1995-10-01

    In a prospective study 32 patients underwent CT-A after stent placement in the iliac arteries. The vascular morphology was analyzed regarding neointimal hyperplasia and calcification pattern. The results were compared with those of clinical findings (walking distance), Doppler ultrasound (ankle-brachial index) and DSA. All 47 stents were visible and patent (100%). One misplacement was identified. A good correlation was found between an improved ankle-brachial index and CT-A (88.5%) and extension of the walking distance and CT-A (92.3%). Concerning location, number and grade of stenoses the results between CT-A and DSA matched in 42.1%. An exact mapping of calcified plaques was possible in all cases. (orig./MG) [Deutsch] Nach perkutaner transluminaler Angioplastie (PTA) und Stenteinlage wurden 32 Patienten prospektiv mittels CT-A untersucht. Es erfolgte eine Analyse der Gefaessmorphologie hinsichtlich neointimaler Hyperplasien und Verkalkungsmuster. Weiterhin wurden die Ergebnisse mit denen der intraarteriellen digitalen Subtraktionsangiographie (i.a. DSA), dem klinischen Befund (Gehstrecke) und der Doppler-Ultraschalluntersuchung (Arm-Knoechel-Index/AKI) verglichen. Alle 47 Stents konnten in der CT-A exakt lokalisiert und als offen identifiziert werden (100%). Eine Stentfehllage wurde diagnostiziert. Der Nachweis neointimaler Hyperplasie gelang aufgrund von Metallartefakten im Stentniveau nicht. Verkalkungen waren in allen Faellen nachweisbar. Eine Uebereinstimmung zwischen DSA und CT-A hinsichtlich des Schweregrades, der Anzahl und Lokalisation von Stenosen fand sich nur in 42,1%. In 88,5% der Faelle bestand eine Uebereinstimmung zwischen CT-morphologischem Befund und verbessertem AKI, in 92,3% mit verlaengerter Gehstrecke. (orig./MG)

  8. 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.

  9. 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)

  10. Efficacy of spiral CT in the evaluation of peritoneal seeding of gastric cancer

    To determine usefulness of spiral CT in the preoperative evaluation of peritoneal seeding from a gastric carcinoma. From a database of 411 consecutive patients with surgically proven advanced gastric cancinoma obtained over a six-month period, 17 with peritoneal seeding and a control group of 24 without peritoneal seeding underwent spiral CT scanning with 7-8 mm scan thickness and interval during the portal phase. Preoperative CT images were analyzed by two readers who reached a consensus with regard to the presence and location of the ascites, thickening of the parietal peritoneum, and changes in the omentum and mesentery. Ascites was present in 47% (8/17) of patients with peritoneal seeding the right subhepatic space (n=6, 35%) and right paracolic gutter (n=5, 29%)-but not the cul-de-sac (n=2, 12%)-were common sites of fluid collection. Permeative changes in the omentum and mesentery were seen in 18% (3/17) and 12% (2/17) of patients, respectively. Among five controls with false positive results, ascites in the cul-de-sac was present in three (two males and one female, 12%) while omental nodules and a thickened peritoneum were found in two (8%) and one (4%), respectively. In nine controls with false negative results, small disseminated nodules were seen in the mesentery and omentum at surgical field. The sensitivity and specificity of spiral CT were 47% (8/17) and 79% (19/24), respectively. In terms of sensitivity and specificity, spiral CT is not especially accurate in distinguishing peritoneal seeding from gastric carcinoma

  11. Virtual endoscopy using spiral CT in patients with carcinomas of the hypopharynx and larynx

    Song, Sang Gook; Seo, Jeong Jin; Chung, Tae Woong; Kim, Hyeong Kil; Jeong, Gwang Woo; Jeong, Yong Yeon; Kang, Heoung Keun; Cho, Jae Sik [Medical School, Chonnam University, Kwangju (Korea, Republic of)

    2000-05-01

    To compare the usefulness of virtual endoscopy using spiral CT with that of laryngoscopy in the detection and evaluation of laryngeal and pharyngeal carcinomas. Twenty-four patients with pathologically proven laryngeal and pharyngeal carcinomas underwent laryngoscopy and virtual endoscopy using spiral CT. Eleven of the carcinomas were supraglottic, five were glottic, and eight were hypopharyngeal. Source images obtained by spiral CT were transmitted to an independent workstation and virtual endoscopic images were obtained using Navigator software. These were graded according to their quality (good, fair, bad), and were interpreted by two radiologists who were blinded to the conventional endoscopic findings. These latter were subsequently compared with the virtual endoscopic findings in terms of similarity to laryngoscopic examination and detectability of lesions. The overall image quality of virtual endoscopy was good in 16 cases (67%), fair in eight (33%), and bad in no case. Among the 11 supraglottic carcinomas, image quality was good in seven cases (64%), and fair in four (36%). In four of the five glottic carcinomas (80%) quality was good, and in one case (20%) it was fair, while among the eight hypopharyngeal carcinomas, quality was good in five cases (63%), and fair in three (37%). Overall, detection of the lesion was possible in 23 cases (96%). Due to the small size of the lesion, the one case of glottic carcinoma was not detected. Virtual endoscopy using spiral CT is a safe and noninvasive method, and also successfully detects laryngeal and pharyngeal lesions, with good image quality. For the evaluation of laryngeal and hypopharyngeal carcinoma, its use ma complement that of axial CT. (author)

  12. Evaluation of triphasic contrast enhanced spiral CT for diagnosing hepatocellular adenoma (report of 5 cases)

    Objective: To evaluate the diagnostic and differential value of triphasic, especially the arterial phase, contrast enhanced CT scans for the hepatocellular adenoma, and to improve CT diagnostic accuracy. Methods: Spiral CT scanning of pre- and post-contrast arterial phase, portal venous phase and delayed phase was performed in 5 patients with hepatocellular adenomas proved surgically and pathologically. The enhancement was administrated with venous injection of 3 ml/sec, totally 100 ml angiografin. Arterial phase of contrast-enhanced scanning started 20-30 sec, portal venous phase 60-70 sec and delay scanning 3 min after the injection of contrast medium. The degrees of the enhancement of adenoma and normal tissues of liver in the three contrast enhanced phases were calculated and compared statistically. Results: In plain CT, the lesions were iso-density in 4 cases and slight hypo density in 1 case, which was hardly distinguished from the normal tissue. In all 5 cases, the lesions showed marked enhancement in the arterial phase compared with normal tissue of liver (38 HU high), and there were markedly statistical difference (t = 18.94, P 0.05). The mean CT value of hepatocellular adenoma in the arterial phase was much higher than that in portal venous and delay phase, there were statistical differences between them (F = 18.39, P < 0.01). Conclusion: Triphasic contrast enhanced spiral CT scan, especially the arterial phase scan, is valuable in detecting and differentiating hepatocellular adenoma

  13. Cardiac spiral dual-source CT with high pitch: a feasibility study

    Ertel, Dirk; Kalender, Willi A. [University of Erlangen-Nuernberg, Institute of Medical Physics (IMP), Erlangen (Germany); Lell, Michael M. [University of Erlangen-Nuernberg, Department of Radiology, Erlangen (Germany); Harig, Frank [University of Erlangen-Nuernberg, Center of Cardiac Surgery, Erlangen (Germany); Flohr, Thomas; Schmidt, Bernhard [Siemens Healthcare, Forchheim (Germany)

    2009-10-15

    Increase of pitch in spiral CT decreases data acquisition time; dual-source CT (DSCT) systems provide improved temporal resolution. We evaluated the combination of these two features. Measurements were performed using a commercial DSCT system equipped with prototype software allowing pitch factors from p=0.35 to 3.0. We measured slice sensitivity profiles as a function of pitch to assess spatial resolution in the z-direction and the contrast of structures moved periodically to measure temporal resolution. Additionally we derived modulation transfer functions to provide objective parameters; both spatial and temporal resolution were essentially unchanged even at high pitch. CT of the cardiac region of three pigs was performed at p=3.0. In vivo CT images confirmed good image quality; direct comparison with standard low-pitch phase-correlated CT image datasets showed no significant difference. For a normalized z-axis acquisition of 12 cm, the corresponding effective dose value was 2.0 mSv for the high-pitch CT protocol. We conclude that spiral DSCT imaging with a pitch of 3.0 can provide unimpaired image quality with respect to spatial and temporal resolution. Applications to cardiac and thoracic imaging with effective dose below 1 mSv are possible. (orig.)

  14. Clinical application of 64-slices spiral CT angiography in diagnosing subarachnoid hemorrhage and Nursing care%64层螺旋CT血管造影在蛛网膜下腔出血诊断的临床运用及护理

    黎兴华

    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)病因诊断中的运用及护理.方法:对2005年9月~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CTA确诊.CTA对SAH病因诊断中的敏感性和特异性均为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,做好检查时的护理配合,可使血管的空间立体结构及周边关系显示良好,有助于治疗方法的选择和难度的评估.

  15. 64排螺旋CT与血清肿瘤标志物联合检测在肺癌诊断中的价值%THE VALUE OF 64-SLICE SPIRAL CT COMBINED WITH SERUM TUMOR MARKERS FOR THE DIAGNOSIS OF LUNG CANCER

    杨晋

    2014-01-01

    目的 探讨64排螺旋CT与血清肿瘤标志物联合检测在肺癌诊断中的价值,旨在为肺癌的临床诊断提供参考.方法 选取55例肺癌患者(观察组)和50例肺部良性病变者(对照组),分别采用64排螺旋CT扫描、检测血清肿瘤标志物如癌胚抗原(CEA)、细胞角质素片段抗原21-1(CYFRA 21-1)及神经元特异性烯醇化酶(NSE)等指标,分析血清肿瘤标志物、CT单独检测以及联合检测的敏感性和特异性.结果 观察组CEA、CYFRA 21-1及NSE水平均高于对照组,且二组比较差异有统计学意义(P<0.05);血清肿瘤标志物与CT扫描联合诊断的特异性(92.2%)和敏感性(90.2%)均明显提高.结论 血清肿瘤标志物与CT扫描联合用于肺癌的诊断,可进一步提高肺癌诊断的准确性、特异性及敏感性,对于肺癌的临床诊断具有重要的应用价值.

  16. 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)

  17. SPECT/spiral-CT hybrid imaging in unclear foci of increased bone metabolism: a case report

    In bone scintigraphy, the differentiation between degenerative processes and bone metastases is still difficult. Therefore, additional radiological studies are regularly needed after bone scintigraphy. The now introduced hybrid-cameras combining single-photon emission computed tomography (SPECT) and spiral-CT are unique in the sense that they offer the opportunity to correlate the functional information with morphology in one session. We herein present two patients in whom this technological setup allowed a definite diagnosis in scintigraphically unclear vertebral lesions. In a patient with breast cancer, hypermetabolic lesions were clearly correlated with osteolyses. In another patient with synovial carcinoma, spondylosis and spondylarthrosis caused focal tracer uptake in the lumbar spine. In addition to an improved diagnostic accuracy, SPECT/Spiral-CT will considerably abbreviate the diagnostic process. (orig.)

  18. SPECT/spiral-CT hybrid imaging in unclear foci of increased bone metabolism: a case report

    Roemer, W.; Kuwert, T. [Nuklearmedizinische Klinik, Friedrich-Alexander-Univ. Erlangen/Nuernberg (Germany); Beckmann, M.W. [Frauenklinik, Friedrich-Alexander-Univ. Erlangen/Nuernberg (Germany); Forst, R. [Lehrstuhl fuer Orthopaedie mit Orthopaedischer Chirurgie, Friedrich-Alexander Univ. Erlangen/Nuernberg (Germany); Bautz, W. [Radiologisches Inst., Friedrich-Alexander-Univ. Erlangen/Nuernberg (Germany)

    2005-07-01

    In bone scintigraphy, the differentiation between degenerative processes and bone metastases is still difficult. Therefore, additional radiological studies are regularly needed after bone scintigraphy. The now introduced hybrid-cameras combining single-photon emission computed tomography (SPECT) and spiral-CT are unique in the sense that they offer the opportunity to correlate the functional information with morphology in one session. We herein present two patients in whom this technological setup allowed a definite diagnosis in scintigraphically unclear vertebral lesions. In a patient with breast cancer, hypermetabolic lesions were clearly correlated with osteolyses. In another patient with synovial carcinoma, spondylosis and spondylarthrosis caused focal tracer uptake in the lumbar spine. In addition to an improved diagnostic accuracy, SPECT/Spiral-CT will considerably abbreviate the diagnostic process. (orig.)

  19. Spiral CT vesiculography: a new method for examining patients with histologically confirmed prostate carcinoma

    Purpose: Development of an imaging method for detection of seminal vesicle invasion in patients with histologically proven carcinoma of the prostate. Materials and methods: In 24 patients with histologically proven carcinoma of the prostate we preoperatively performed an antegrade vaso-vesiculography with non-ionic, iodine-containing contrast agent followed by a spiral CT of the seminal vesicles. Results: In 21 patients we achieved both a bilateral and a bulging enhancement of the seminal vesicle lumen. The method is introduced and described in detail. Conclusions: Intraductal application of contrast agent just before spiral CT results in unfold and bulging enhanced seminal vesicles. From the differentiation of the lumen, the wall, and the surrounding fat of the seminal vesicles as well as the enhanced ejaculatory ducts we expect information on tumourous infiltration in cases of histologically proven carcinomas of the prostate. (orig.)

  20. Preliminary clinical experience of spiral CT virtual colonoscopy for detection of colorectal polyps

    Objective: To evaluate spiral CT virtual colonoscopy (SCT VC) for detection of colorectal polyps. Methods: Spiral CT (SCT) was performed in 18 patients with breath holding. All data sets acquired with 4-5 mm collimation and overlapping reconstruction 50%-70% from SCT were transferred to workstation, and various opacities were assigned to generate SCTVC view. The results of SCT VC were confirmed by fibreoptic colonoscopy and (or) surgery. Results: SCTVC detected 71 colorectal polyps in 9 patients. One polyp was flat, while the others were sessile with dimension from 2 mm to 13 mm except 1 with 20 mm. Polyps 5 mm were well delineated and the number, size , morphology, and exact location could be ascertained. The sensitivity of SCTVC for polyp detection was >82%. Conclusion: SCTVC is a reliable, rapidly evolving technology that provides computer-simulated endoscopic visualization of the colonic polyps

  1. Virtual bronchoscopy of pediatric patients based on multislice spiral CT (MSCT): initial clinical experience; Virtuelle Bronchoskopie am Kind unter Verwendung der Mehrzeilen-Spiral-CT: erste klinische Erfahrungen

    Kirchner, J.; Laufer, U.; Jendreck, M.; Kickuth, R.; Schilling, E.M.; Liermann, D. [Katholisches Marienhospital Herne (Germany). Klinik fuer Radiologische Diagnostik und Nuklearmedizin

    2000-07-01

    We demonstrate the benefit of the accelerated examination based on multislice spiral CT (MSCT) in the pediatric patient which has not been reported so far. Material and methods: MSCT (tube voltage 120 kV, tube current 110 mA, 4x1 mm slice thickness, 500 ms rotation time, pitch 6) was performed on a CT scanner of the latest generation (Volume Zoom, Siemens Corp., Forchheim, Germany). In total we examined 11 patients. Results: In all patients we obtained sufficient data for 3D reconstruction avoiding general anesthesia. 6/11 examinations were described to be without pathological finding. A definite diagnosis was obtained in 10 patients. Virtual bronchoscopy could avoid other invasive diagnostic examination in 8/11 patients. (orig.) [German] Wir berichten von unseren Erfahrungen mit der bislang noch nicht beschriebenen, durch die Anwendung der Mehrzeilen-Spiral-Computertomographie (MSCT) verbesserten virtuellen Bronchoskopie des Kleinkindes. Material und Methode: Die MSCT (120 kV Roehrenspannung, 110 mA Roehrenstrom, Schichtdicke 4x1 mm, Pitch 6, 500 ms Rotationszeit) wurde an einem Computertomographen der neusten Generation durchgefuehrt (Volume Zoom, Siemens AG, Forchheim). Insgesamt wurden 11 Patienten untersucht. Ergebnisse: Bei allen Patienten konnten fuer die 3D-Nachbearbeitung verwendbare Datensaetze ohne Durchfuehrung einer Narkose erhoben werden. Eine definitive Diagnose wurde anhand der virtuellen Bronchoskopie in 10 Faellen erhoben, hiervon wurden 6 Untersuchungen als unauffaellig bezueglich des Tracheobronchialsystems beschrieben. Die virtuelle Bronchoskopie konnte eine weitere invasive diagnostische Untersuchung in 8/11 Faellen vermeiden. (orig.)

  2. Technique and value of three dimensional reconstruction of stones in the renal pelvis using spiral CT

    5 patients with staghorn calculi in the renal pelvis were examined by spiral CT. From the raw data three dimensional reconstructions of the stones were obtained. In all patients it was possible to compare the three dimensional model with the stone following performance of percutaneous lithopaxy and endoscopic removal of the fragments. In all cases the three dimensional reconstruction provided a realistic image of the stones and was of practical value for the urologist for preoperative diagnosis and intraoperative control. (orig.)

  3. 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...

  4. Thromboembolic Complications Following Spine Surgery Assessed with Spiral CT Scans: DVT/PE Following Spine Surgery

    Kim, Han Jo; Walcott-Sapp, Sarah; Adler, Ronald S.; Pavlov, Helene; Boachie-Adjei, Oheneba; Westrich, Geoffrey H.

    2010-01-01

    Spine surgery is associated with a significant risk of postoperative pulmonary embolism (PE) and/or deep vein thrombosis (DVT). The goal of this study was to determine which symptoms and risk factors were associated with spiral CT scans positive for PE and/or DVT in the postoperative spine surgery patient. We conducted a retrospective review of all spine patients who underwent a postoperative CT to rule out PE during the period of March 2004–February 2006. The type of surgical procedure, risk...

  5. Spiral CT in kidney: assumption of renal function by objective evaluation of renal cortical enhancement

    To correlate the degree of renal cortical enhancement, objectively evaluated by means of spiral CT with the serum level of creatinine, and to determine the extent to which this degree of enhancement may be used to detect renal parenchymal disease. Eighty patients (M:F = 50:30; age + 25-19, (mean 53) years) with available serum level of creatinine who underwent spiral CT between September and October 1999 were included in this study. In fifty patients the findings suggested hepatic or biliary diseases such as hepatoma, biliary cancer, or stone, while in thirty, renal diseases such as cyst, hematoma, or stone appeared to be present. Spiral CT imaging of the cortical phase was obtained at 30-40 seconds after the injection of 120 ml of non-ionic media at a rate of 3 ml/sec. The degree of renal cortical enhancement was calculated by dividing the CT attenuation number of renal cortex at the level of the renal hilum by the CT attenuation number of aorta at the same level. The degree of renal cortical enhancement was compared with the serum level of creatinine, and the degree of renal cortical enhancement in renal parenchymal disease with that of the normal group. Among eighty patients there were five with renal parenchymal disease and 75 with normal renal function. The ratio of the CT attenuation number of renal cortex to that of aorta at the level of the renal hilum ranged between 0.49 and 0.99 (mean, 0.79; standard deviation, 0.15). while the serum level of creatinine ranged between 0.6 and 3.2 mg/dl. There was significant correlation (coefficient of -0.346) and a statistically significant probability of 0.002 between the ratio of the CT attenuation numbers and the serum level of creatinine. There was a significant difference (statistically significant probability of less than 0.01) between those with renal parenchymal disease and the normal group. The use of spiral CT to measure the degree of renal cortical enhancement provides not only an effective index for

  6. Spiral CT of hepatocellular carcinoma: value of dynamic fast infusion of contrast material

    To assess the value of dynamic fast infusion of contrast material in the detection and diagnosis of hepatocellular carcinoma(HCC) with spiral CT. Two-phase dynamic spiral CT was performed in 59 patients with 104 HCCS. 150ml of nonionic contrast material was injected with an automatic injector at the rate of 5ml/sec. Two-phase images were obtained at 20-45 sec(arterial dominant phase) and 2-5 min(equilibrium phase) after the initiation of bolus injection of contrast material. The tumors were divided into three groups(5cm) according to the size and the enhancement patterns on two-phase images were compared. In the arterial phase, HCCs showed total or partial hyperattenuation in 79% of cases(82/104), isoattenuation in 12%, and hypoattenuation in 9%. In the equilibrium phase, HCCs showed hypoattenuation in 86%(89/104) and isoattenuation in 14%. The most common and characteristic enhancement patterns of HCCs were hyperattenuation in the arterial phase and hypoattenuataion in the equilibrium phase;in the latter, capsules were demonstrated in 45% of cases. Invasions of the portal and/or hepatic vein were demonstrated in 34% of cases. Dynamic fast infusion(5 ml/sec) of contrast material(150ml)is useful in the detection and diagnosis of HCCs with spiral CT

  7. Power doppler ultrasound findings of renal infarct after experimental renal artery occlusion: comparison with spiral CT

    To evaluate the efficacy of power Doppler ultrasonography (PDUS) in depicting renal infarction in rabbits during experimental renal segmental arterial occlusion, and to compare the results with those of CT scanning. In 28 rabbits weighing 2.5 4kg, the segmental renal artery was occluded through the left main renal artery by embolization with Ivalon (Nycomed, Paris, France). Power Doppler ultrasonography and spiral CT scanning were performed before and at 2, 5, 8, 15, and 24 hours, and 3 and 7 days after occlusion of the segmental renal artery. The location of infarcted areas and collaterals, as seen on PDUS and CT scans, was evaluated by two radiologists. In all cases, as seen on power Doppler ultrasonography, infarcted areas-when compared with normal parenchyma, clearly demonstrated wedge-shaped perfusion defects in the kidney. The location of the lesion closely corresponded to the location seen during CT scanning. After renal arterial occlusion, transiently congested capsular arteries, which were named 'capsular sign', were seen in 63% of rabbits in the two and five-hour groups. No significant cortical rim sign was demonstrated on power Doppler ultrasonography, though it was noted on spiral CT at 15 and 24 hours, and 3 and 7 days after renal arterial occlusion. Power Doppler ultrasonography was useful for the diagnosis of renal infarction. Congested capsular artery seen in the early stage of renal infarction might be a characteristic finding of this condition, as seen on power Doppler ultrasonography

  8. Pulmonary spheral tuberculosis: features and clinical significance of spiral dynamic CT

    Objective: To assess the features and clinical significance of spiral dynamic CT in patients with pulmonary spheral tuberculosis. Methods: The 54 foci in 42 patients with pulmonary spheral tuberculosis were studied. Thin-sections at 2 mm thickness and 2 mm interval through the nodular center were obtained before and after administration of contrast material. Results: In 54 pulmonary spheral tuberculosis, maximum enhanced CT value in 51 (94.4%, 51/54) foci was less than 20 HU, and more than 20 HU in the other 3(5.6%, 3/54) foci. 27(50.0%, 27/54) foci showed no any enhancement, 24, (44%, 24/54) foci showed capsular enhancement, 1(1.9%, 1/54) focus showed peripheral enhancement and 2(3.7%, 2/54) foci showed extensive enhancement. The accuracy of the correct diagnosis was 25.9% in terms of plain CT and 94.4% in terms of enhanced CT scanning. The difference was significant (x2 = 50.1, P < 0.05). The curative effect of extensive enhanced foci and peripheral enhanced foci was optimal, capsular enhanced foci was second, and non-enhanced foci was barely satisfactory. Conclusion: Spiral dynamic CT technique may improve the accuracy of diagnosing pulmonary spheral tuberculosis. No enhancement and/or capsular enhancement were suggestive of tuberculosis. The enhancing character of foci might contribute to assess the curative effect of anti-tuberculosis

  9. Virtual endoscopy of the upper respiratory tract using spiral CT

    Purpose: The technical conditions, the optimized scanning protocols and the facilities of virtual endoscopy (VE) are presented in an overview. Methods: Phantom studies showed that, for a single-row-detector helical CT, collimation of 3.0 mm combined with pitch of 1.5 provided an optimal compromise between image quality and the scan duration per breath-hold. A multi-row-detector helical CT requires only a fraction of the scanning time. This is especially important for patients with dyspnea. Results: The threshold-dependent virtual endoscopic surface rendering is a reliable and rapidly practicable reconstruction algorithm for the imaging of the upper airway. Conclusions: The VE technique is suitable for the imaging of space-occupying tumors and restricted stenoses. With VE follow-up examinations can be performed non-invasively and interventional procedures can be prepared in an optimal way. Because of the computed tomographic data acquisition the structure of the mucosa is not assessable and there is no opportunity to obtain a biopsy specimen. (orig.)

  10. 螺旋CT平扫及重建技术辅助上颌前牙种植15例%Case report of 15 dental implantation assisted with spiral CT in anterior region of maxilla

    王仁欣; 张占利; 董鹏飞

    2013-01-01

    Objective: To evaluate the clinical efficiency of 64-slice spiral CT in the anterior maxilla. Methods:15 patients with delayed implantation in anterior region of maxilla was examed with CT scan and/or 3D reconstruction, and dental implantation doctors account for the complications and assisted surgery operation of implantation, and get the advantage of CT images VS X-Ray. Results: CT images can stereoscopically and directly reveal the height, width and density of the implantation zone,which helps dental implantation doctors to have a fluent communication with patients. Conclusion:CT images can provide reliable evidence for planning a precise surgery and benefit doctors communicating with their patients. CT scan should be suggested an necessary examine in implantation of anterior maxilla.%  目的:探讨采用64排CT平扫及重建技术在上颌前牙种植中应用的临床意义。方法:对我科近2年来上颌前牙延期种植患者术前进行64排CT平扫/(及)重建,根据CT结果,进行术前分析设计,与患者沟通解释种植手术所需要的其他辅助操作及手术并发症,总结CT图像对手术的指导意义及在医患沟通方面的优势。结果:CT扫描能清晰地显示出种植区骨密度、骨厚度及高度情况,有利手术方案的制定,增强了种植医师对手术解释的说服力和医患之间的信任程度,更有利医患沟通。结论:上颌前牙种植前的CT扫描检查对上颌前牙种植的术前指导及医患沟通具有重要的临床意义,建议CT扫描做为上颌前牙种植前的常规检查。

  11. Visual classification of emphysema heterogeneity compared with objective measurements: HRCT vs spiral CT in candidates for lung volume reduction surgery

    The aim of this study was to investigate whether spiral CT is superior to high-resolution computed tomography (HRCT) in evaluating the radiological morphology of emphysema, and whether the combination of both CT techniques improves the evaluation in patients undergoing lung volume reduction surgery (LVRS). The material consisted of HRCT (with 2-mm slice thickness) and spiral CT (with 10-mm slice thickness) of 94 candidates for LVRS. Selected image pairs from these examinations were evaluated. Each image pair consisted of one image from the cranial part of the lung and one image from the caudal part. The degree of emphysema in the two images was calculated by computer. The difference between the images determined the degree of heterogeneity. Five classes of heterogeneity were defined. The study was performed by visual classification of 95 image pairs (spiral CT) and 95 image pairs (HRCT) into one of five different classes of emphysema heterogeneity. This visual classification was compared with the computer-based classification. Spiral CT was superior to HRCT with 47% correct classifications of emphysema heterogeneity compared with 40% for HRCT-based classification (p<0.05). The combination of the techniques did not improve the evaluation (42%). Spiral CT is superior to HRCT in determining heterogeneity of emphysema visually, and should be included in the pre-operative CT evaluation of LVRS candidates. (orig.)

  12. Risk-benefit analysis and cost-effectiveness analysis of lung cancer screening by spiral CT

    Mass screening of lung cancer has been widely performed using indirect chest X-ray method in Japan. However reduction of the mortality for lung cancer is questioned. We have proposed that recently developed spiral CT should be adopted for the screening of lung cancer, since CT has an excellent detectability for small nodule. Lung Cancer Screening CT (LSCT) has been developed by author's group using spiral CT with low dose and light weight in order to make a mobile unit. In this paper risk-benefit analysis and cost-effectiveness analysis are described for the LSCT screening of lung cancer. As a risk, radiation carcinogenesis due to exposure from LSCT are compared with gain of life-expectancy by screening and men of 40 years or more and women of 45 years or more are justified. The cost per person-year is estimated for LSCT screening which is better than that of present method, although total cost is higher. The LSCT screening could be recommended if total cost is affordable. (author)

  13. The usefulness of thin-section spiral CT in the evaluation of mediastinal lymph node metastasis from non-small cell lung cancer : a prospective study and comparison with thick-section spiral CT

    To compare the accuracy of thick-and thin-section spiral CT and to determine whether, in diagnosing mediastinal lymph node metastasis from non-small cell lung cancer, the latter is superior to the former. Between March 1997 and March 1998, 51 patients with pathologically proven non-small cell lung cancer underwent thoracotomy with full nodal dissection. Thick- and thin-section spiral CT were performed in all patients, with a mean interval of 14 days. The former was performed with 10 mm thickness and 10 mm interval, and the lather with 3 mm thickness and 3 mm interval. Mediastinal lymph nodes were localized according to the lymph node mapping scheme of the American Thoracic Society and were considered positive for metastasis if they exceeded 10 mm in short-axis diameter. A total of 227 mediastinal nodal stations in 51 patients were obtained. Of these, 188 stations included in thin-section spiral CT were analyzed and the prevalence of mediastinal nodal metastasis was found to be 10%. On a station-by-station basis, and for thick- and thin-section spiral CT, respectively, the overall sensitivities of mediastinal lymph node metastasis were 32% and 53% (p less than .05), while specificities were 91% and 92% (p greater than .05). Although there were no statistically significant differences in sensitivity and specificity according to nodal station, thin-section spiral CT tended to be superior to the thick-section type for stations 7 and 10R in terms of sensitivity, and for stations 4L and 5 in terms of specificity. Thin-section spiral CT was more sensitive than thick-section spiral CT is the evaluation of mediastinal lymph node metastasis from non-small cell lung cancer. This may be due to the higher resolution of the former and its ability to discriminate between lymph node and vessel. (author)

  14. The usefulness of thin-section spiral CT in the evaluation of mediastinal lymph node metastasis from non-small cell lung cancer : a prospective study and comparison with thick-section spiral CT

    Kim, Ji Hoon; Lee, Jin Sung; Sohn, Kwang Hyun; Park, Seung Il; Song, Koun Sik; Lim, Tae Hwan [Asan Medical Center, College of Medicine, University of Ulsan, Seoul (Korea, Republic of); Kim, Hyae Young [Mokdong Hospital, Ewha Womams University, Seoul (Korea, Republic of)

    2000-05-01

    To compare the accuracy of thick-and thin-section spiral CT and to determine whether, in diagnosing mediastinal lymph node metastasis from non-small cell lung cancer, the latter is superior to the former. Between March 1997 and March 1998, 51 patients with pathologically proven non-small cell lung cancer underwent thoracotomy with full nodal dissection. Thick- and thin-section spiral CT were performed in all patients, with a mean interval of 14 days. The former was performed with 10 mm thickness and 10 mm interval, and the lather with 3 mm thickness and 3 mm interval. Mediastinal lymph nodes were localized according to the lymph node mapping scheme of the American Thoracic Society and were considered positive for metastasis if they exceeded 10 mm in short-axis diameter. A total of 227 mediastinal nodal stations in 51 patients were obtained. Of these, 188 stations included in thin-section spiral CT were analyzed and the prevalence of mediastinal nodal metastasis was found to be 10%. On a station-by-station basis, and for thick- and thin-section spiral CT, respectively, the overall sensitivities of mediastinal lymph node metastasis were 32% and 53% (p less than .05), while specificities were 91% and 92% (p greater than .05). Although there were no statistically significant differences in sensitivity and specificity according to nodal station, thin-section spiral CT tended to be superior to the thick-section type for stations 7 and 10R in terms of sensitivity, and for stations 4L and 5 in terms of specificity. Thin-section spiral CT was more sensitive than thick-section spiral CT is the evaluation of mediastinal lymph node metastasis from non-small cell lung cancer. This may be due to the higher resolution of the former and its ability to discriminate between lymph node and vessel. (author)

  15. High-resolution virtual laryngoscopy based on helical CT data sets; Hochaufloesende virtuelle Laryngoskopie aus Spiral-CT-Datensaetzen

    Aschoff, A.J.; Seifarth, H.; Fleiter, T.; Sokiranski, R.; Goerich, J.; Merkle, E.M.; Wunderlich, A.P.; Brambs, H.J. [Universitaetsklinikum Ulm (Germany). Abt. fuer Diagnostische Radiologie; Zenkel, M.E. [Universitaetsklinikum Ulm (Germany). Hals-Nasen-Ohrenheilkunde

    1998-10-01

    This pilot study investigated the feasibility and clinical value of high-resolution virtual real-time laryngoscopy based on helical CT data sets. Nine patients with laryngeal pathology (three with tumors of the vocal cords, two laryngeal carcinomas, one with invasion of the larynx by thyroid carcinoma and six subglottic stenoses) underwent examination by helical CT at a collimation of 1 mm. Following acquisition, the images were processed at a workstation with standard visualization software, such that virtual endoscopy (VE) in real time was possible. The images were then compared with the findings of conventional endoscopy. Because of swallowing artifacts, reconstruction failed in 2 of 12 patients. None of the carcinomas of the vocal cords was recognized at VE or in the cross-sectional CT images. VE provided the correct diagnosis in 8 of 12 cases (laryngeal tumors, subglottic stenoses). Virtual laryngoscopy is capable of simulating the visual findings of endoscopy in cases of laryngeal tumors and subglottic stenoses. Small tumors of the vocal cords are not adequately visualized. The major problem affecting results is motion artifacts resulting from involuntary swallowing. (orig.) [Deutsch] Im vorliegenden Beitrag wird eine Pilotstudie zur Ueberpruefung der Machbarkeit und des klinischen Nutzens einer hochaufloesenden virtuellen Echtzeitlaryngoskopie aus Spiral-CT-Datensaetzen vorgestellt. 12 Patienten mit Erkrankungen im Kehlkopfbereich (3 Stimmlippentumore, 2 Larynxkarzinome, ein in den Larynx eingebrochenes Schilddruesenkarzinom und 6 subglottische Stenosen) wurden mittels hochaufloesender Spiral-CT (Kollimation 1 mm) untersucht. Anschliessend wurden die Bilder auf einer Workstation mit einer standardmaessigen Visualisierungssoftware so rekonstruiert, dass eine virtuelle Endoskopie (VE) in Echtzeit moeglich wurde, welche der herkoemmlichen Fiberendoskopie gegenuebergestellt wurde. 2 der 12 Patienten waren bedingt durch Schluckartefakte nicht zu rekonstruieren

  16. 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.

  17. 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

  18. Spiral CT scanning technique in the detection of aspiration of LEGO foreign bodies

    Background:. Radiolucent foreign bodies (FBs) such as plastic objects and toys remain difficult to identify on conventional radiographs of the neck and chest. Children may present with a variety of respiratory complaints, which may or may not be due to a FB. Objective: To determine whether radiolucent FBs such as plastic LEGOs and peanuts can be seen in the tracheobronchial tree or esophagus using low-dose spiral CT, and, if visible, to determine the optimal CT imaging technique. Materials and methods: Multiple spiral sequences were performed while varying the CT parameters and the presence and location of FBs in either the trachea or the esophagus first on a neck phantom and then a cadaver. Sequences were rated by three radiologists blinded to the presence of a FB using a single scoring system. Results: The LEGO was well visualized in the trachea by all three readers (both lung and soft-tissue windowing: combined sensitivity 89 %, combined specificity 89 %) and to a lesser extent in the esophagus (combined sensitivity 31 %, combined specificity 100 %). The peanut was not well visualized (combined sensitivity < 35 %). The optimal technique for visualizing the LEGO was 120 kV, 90 mA, 3-mm collimation, 0.75 s/revolution, and 2.0 pitch. This allowed for coverage of the cadaver tracheobronchial tree (approximately 11 cm) in about 18 s. Although statistical power was low for detecting significant differences, all three readers noted higher average confidence ratings with lung windowing among 18 LEGO-in-trachea scans. Conclusion: Rapid, low-dose spiral CT may be used to visualize LEGO FBs in the airway or esophagus. Peanuts were not well visualized. (orig.)

  19. 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.

  20. Differential diagnosis of gallbladder wall thickening by two phase spiral CT : gallbladder carcinoma versus cholicystitis

    Park, Sun; Cho, Soon Gu; Kim, Mi Young; Woo, Je Hong; Shin, Seok Hwan; Lee, Kykung Hee; Suh, Chang Hae [Inha Univ. College of Medicine, Inchon (Korea, Republic of)

    2001-04-01

    To determine whether an analysis of two-phase CT features provides a sound basis for differential diagnosis between gallbladder carcinoma and cholecystitis. We reviewed a total of 89 cases of gallbladder carcinoma (n=35) or cholecystitis (n=54) in patients who had undergone two-phase spiral CT. For this, a GE Highspeed Advantage scanner (GE Medical Systems, Milwaukee, U . S . A .) was used. A total of 120ml of contrast material was injected at a rate of 2-3 ml/sec. Arterial and venous phase scans were obtained 35 and 65 seconds, respectively, after the initiation of contrast infusion. All cases of gallbladder carcinoma and 468 of cholecystitis (of a total of 482) were confirmed by histopathology. We reviewed the two phase spiral CT features, analyzing and assessing thickness of the lesion, the enhancement pattern seen during the arterial and the venous phase, invasion of liver, pericholecystic fat infiltration, dilatation of intrahepatic ducts, and other associated findings. Mean wall thickness was 12.6 mm in the gallbladder carcinoma group, and 7.2 mm in the cholecystitis group. The common enhancement patterns seen in gallbladder carcinoma were 1) a highly enhanced thick inner wall layer during the arterial phase which became iso attenuated with adjacent liver parenchyma during the venous phase (16/35; 45.7%) and 2) highly enhanced thick inner wall layer during both the arterial and venous phase (8/35; 22.9%). The most common enhancement pattern in cholecystitis cases was an iso attenuated thin inner wall layer during both the arterial and the venous phase (44/54; 81.5%). Findings of intrahepatic mass formation by direct invasion (9/35), lymph node enlargement (12/35), and metastasis to other organs (7/35) occurred only in cases of gallbladder carcinoma (18/35, 51.4%) than of cholecystitis (10/54, 18.5%). The incidence of pericholecystic fat infiltration and fluid collection was not significantly different between the gallbladder cancer and cholecystitis groups

  1. Dosimetry in dental radiology. Dentascan spiral CT versus panoramic radiography; Dosimetria nella radiologia odontostomatologica: confronto tra tomografia computerizzata spirale e ortopantomografia

    Villari, N.; Stecco, A.; Zatelli, G. [Florence Univ., Florence (Italy). Dipt. di fisiopatologia clinica

    1999-05-01

    The study compares the doses absorbed by the dentomaxillary area in spiral CT and panoramic examinations. The dose measurements demonstrate that patients receive smaller doses with panoramic radiography than with spiral CT with Dentascan. After following for some variations from instrumental differences, they are in substantial agreement with literature data. Further investigations are needed considering the radiobiological risk related to the growing spread of Dentascan examinations. [Italian] Questo lavoro intende confrontare le dosi assorbite nel distretto dento-mascellare, con le due principali tecniche utilizzate in questo campo: TC spirale e ortopantomografia. Emerge come l'esame panoramico delle arcate dentarie eseguito con l'ortopantomografo comporti la'ssorbimento di dosi inferiori rispetto a quelle dell'esame TC spirale con programma Dentascan. Questi dati, pur essendo soggetti a variabilita' dovuta alla strumentazione utilizzata, sono paragonabili a quelli di altri studi e impongono ulteriori approfondimenti dato il crescente ricorso degli implantologi alla TC spirale con programma di ricostruzione Dentascan.

  2. 3-D CT for cardiovascular treatment planning

    Wildermuth, S.; Leschka, S.; Duru, F.; Alkadhi, H. [Inst. for Diagnostic Radiology, Univ. Hospital Zurich (Switzerland)

    2005-11-15

    The recently developed 64-slice CT scanner together with the use of 2-D and 3-D reconstructions can aid the cardiovascular surgeon and interventional radiologist in visualizing exact geometric relationships to plan and execute complex procedures via minimally invasive or standard approaches.Cardiac 64-slice CT considerably benefits from the high temporal and spatial resolution allowing the reliable depiction of small coronary segments. Similarly, abdominal vascular 64-slice CT became possible within short examination times and allowing an optimal arterial contrast bolus exploitation. We demonstrate four representative cardiac and abdominal examples using the new 64-slice CT technology which reveal the impact of the new scanner generation for cardiovascular treatment planning. (orig.)

  3. The diagnosing value of reconstruction and virtual endoscopy of spiral CT angiography on aortic dissection

    Objective: To evaluate the value of reconstruction and virtual endoscopy of spiral CT angiography in diagnosing aortic dissection. Methods: Seventeen patients with aortic dissection were examined by spiral CT with contrast agent and the post processing included shaded surface display (SSD), maximum intensity projection (MIP), multiplanar reconstruction (MPR), curved planar reconstruction (CPR) and CT virtual endoscopy (CTVE). Results: The true and false lumen, exfoliate intima, calcification, and thrombus could be seen on axial imaging, SCTA, MPR and CTVE. Both the panorama of aortic lesion including exfoliate intima, true and false lumen and its extent, size and involvement of vascular branches could be preferably shown on MIP, CPR and SSD. Calcification of vascular wall could be clearly displayed on MIP. The true and false lumen, exfoliate intima, calcification, thrombus and crevasse could be revealed on MPR because the whole lesion could be reconstructed and observed from any angle on it. Some structures, which were not on the same plane, could be shown on the same two-dimensional plane, but their deep relations could not be done. The true and false lumen, exfoliate intima and crevasse could also be seen on CTVE. Conclusion: axial imaging combined with other imaging techniques of SCTA including MPR, MIP, CPR, SSD and CTVE will roundly display aortic dissection. SCTA will be a reliable and safe method in diagnosing aortic dissection and be able to replace invasive DSA on a certain extent

  4. 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)

  5. Portal venous calcifications 20 years after portosystemic shunting Demonstration by spiral CT with CT angiography and 3D reconstructions

    Background: Evaluation of the value of spiral computed tomography (SCT), and postprocessing procedures in patients with extensive portal venous calcifications 20 years after portosystemic shunting was performed. Methods: In two patients spiral CT (SCT) examinations of the abdomen (slice thickness 3 mm, table feed 6 mm/s) were performed prior and after application of 150 ml of contrast material administered at a flow rate of 4 ml/s. Axial images were reconstructed at 2 mm increments for postprocessing procedures and 6 mm increments for axial source images. Postprocessing was performed with a maximum intensity projection (MIP) and shaded surface display (SSD) imaging program. Results: In both cases preoperative plain film radiography of the chest and abdomen showed large curvilinear calcifications located at the upper quadrant of the abdomen. The calcifications were directed along the expected axis and position of the portal vein and the portosystemic venous anastomosis. Axial CT slices and CTA showed that the calcifications were located in the vessel wall and that the portal vein lumen as well as the portosystemic venous anastomosis were patent. Conclusion: Long-standing portal hypertension is capable of causing portal venous calcifications due to mechanical stress to the vessel wall even years after performing portosystemic shunting. Typically, the calcifications are directed along the expected axis and position of the portal vein. SCT of the portal venous system is a reliable method to differentiate between calcifications in a thrombus or in the vessel wall, which may have therapeutic significance

  6. Multiphasic spiral CT of renal masses: comparison among phases following contrast injection

    To assess the utility of multiphasic spiral CT for characterizing renal masses. The study included 36 patients(53 lesions) referred for the evaluation of renal masses suspected on the basis of the results of sonography or radiography. Spiral CT of the kidneys was performed prior to and following power injection of intravenous contrast material (Optiray-320). Postcontrast imaging data were obtained and analyzed during early and late corticomedullary(20-30-second delay), nephrographic(60-70-second delay), and excretory (5-minute delay) phases. During each phase, the ability to detect renal masses was evaluated, and the ability to diagnose these masses on routine and multiphasic CT was assessed. Routine precontrast and excretory phase CT studies were performed and the usefulness of each phase for the diagnosis of renal cell carcinoma(RCC) and transitional cell carcinoma(TCC) was evaluated. The rates for the detection of renal masses were as follows:94.3% on precontrast scan, 93.8% during the early corticomedulolary phase(ECMP), 98.1% during the late corticomedullary phase(LCMP), 100% during the nephrographic phase(NP), and 98.1% during the excretory phase (EP). During both routine and multiphasic CT, diagnostic accuracy was 96.2%, though for differential diagnosis, multiphasic CT was more helpful than routine CT in 4/16 cases of RCC and 2/8 cases of TCC. The highest for lesion characterization, during the LCMP in RCC, and the LCMP and NP in TCC;for evaluation of tumor margin during the EP in both RCC and TCC; for delineation of the renal artery, during the LCMP in both RCC and TCC;for delineating the renal vein, during the NP in RCC, and the LCMP in TCC. For the detection and correct diagnosis of lesions, multiphasic CT was not superior to routine CT, but for the characterization of RCC and TCC, the former was helpful. The most useful phase can differ according to the kind of renal mass, and so for characterization of the mass, the most appropriate phase must be

  7. Kontrastmittel-MRT (MnDPDP) in der Detektion von Lebermetastasen kolorektaler Karzinome im Vergleich zu Ultraschall, Spiral-CT, Spiral-CTAP und operativem Befund

    Kramer, Hubertus

    2005-01-01

    30 Patienten mit gesichertem kolorektalem Karzinom und V.a.Lebermetastasen wurden zusätzlich zur etablierten präoperativen Diagnostik mit Ultraschall, Spiral-CT und Spiral-CTAP mit MnDPDP verstärkter MRT der Leber untersucht. Bei 18 Patienten konnte eine zeitnahe intraoperative Beurteilung der Leber durchgeführt werden. Es zeigte sich, dass die MRT+MnDPDP der SCTAP bei der Entdeckung von Lebermetastasen zumindest gleichwertig ist. Im Vergleich zu den anderen Verfahren resultierte aufgrund bes...

  8. Analysis of value of multislice spiral CT urography in the diagnosis of upper urinary tract obstruction%多层螺旋 CT 泌尿造影对上尿路梗阻性疾病的诊断价值

    张昊

    2016-01-01

    Objective To investigate the feasibility of the implementation of the urinary tract obstruction in multi - slice spiral CT urography (MSCTU)′s. Methods 27 patients were chosen from May 2014 to May 2015 in our hospital and confirmed by upper urinary tract obstruction unex-plained total,the use of 64 - slice spiral CT for patients MSCTU exploration,the acquired image to the workstation volume rendering(VRT),maxi-mum density contrast( MIP)and multiplanar reconstruction(MPR),study the three - dimensional stereoscopic image processing. Results The group of 27 cases,there are 13 cases belong to urinary stones,five cases belong to congenital malformations,three cases belong to the ureter in-flammatory / adhesions stenosis,and renal cysts huge,extrinsic compression and ureteral tumors in 2 cases. MSCTU diagnosis consistent 27 patients with surgical pathology. Conclusion Patients with upper urinary tract obstruction implementation MSCTU inspection,diagnosis and dif erential value highly suitable for universal use.%目的:探讨在上尿路梗阻性疾病中实施多层螺旋 CT 泌尿造影(MSCTU)的可行性。方法选取2014年5月至2015年5月收录并证实上尿路不明原因梗阻的患者共27例,使用64层螺旋 CT 机对患者进行MSCTU 探查,将获取的图像送至工作站进行容积再现( VRT)、最大密度造影(MIP)与多平面重建(MPR),研究三维处理后的立体图像。结果27例病例中,有13例为泌尿系结石,5例为先天性畸形,3例为输尿管炎性/粘连狭窄,肾巨大囊肿、外源性压迫与输尿管肿瘤各2例。27例患者的 MSCTU 诊断结果与手术病理一致。结论对上尿路梗阻性疾病患者实施 MSCTU 检查,有高度的诊断与鉴别价值,适合普及使用。

  9. Opacification of the urinary tract in portal venous spiral CT without delayed scans

    In portal venous spiral CT there is no visible renal contrast excretion within the usual period of scanning. To opacify collecting systems additional delayed scanning is required. We administered an extra pre-dose of contrast medium before the main portal venous bolus in order to opacify the urinary tract and studied its effects on liver attenuation. In 32 patients examined first by non-contrast spiral CT 20 ml of a non-ionic IV CM were injected. Five minutes later, orientating cuts in the liver and along the urinary tract were obtained. Immediately thereafter, a 120-ml bolus was administered at 3 ml/s for portal venous phase helical CT (60-s delay craniocaudad). The quality of renal excretion was graded visually (excellent, fair, poor, none). Hepatic attenuation measurements were performed at comparable regions of interest. In all patients 20 ml CM opacified the renal pelvis after 5 min. Depiction of the ureters was excellent in 14, fair in 11 and poor or none in 7 cases. There was little effect on mean hepatic attenuation by the 20-ml pre-bolus after 5 min: mean enhancement 2.3 HU (range -0.6 to 7.8 HU). Mean hepatic enhancement after the 120-ml portal venous bolus ranged between 23.6 and 74.1 HU (mean 51.5 HU). When opacification of the urinary tract is necessary, pre-administration of a 20-ml bolus 5 min before portal venous scanning may save an extra delayed spiral. The effects on hepatic enhancement are negligible. (orig.)

  10. A case of occult insulinoma localized by pancreatic dynamic enhanced spiral CT

    2010-01-01

    Insulinomas are the most common category of pancreatic endocrine tumors,with an annual incidence of 1-4 cases per million people.Most are intrapancreatic,benign and solitary.Therefore,they have an excellent prognosis after surgical resection.However,the localization diagnosis of insulinomas still poses a challenge to surgeons and radiologists.In this case,the tumor was occult and could not be found by either abdominal enhanced spiral computed tomography(CT)or ultrasonography.Therefore,we tried a new method ...

  11. The Role of Spiral Multidetector Dynamic CT in the Study of Williams-Campbell Syndrome

    Williams-Campbell syndrome is a cystic bronchiectatic disease secondary to deficiency or defect of cartilaginous plates in the wall of the airways. In the literature, two main forms are suggested: congenital and acquired (post-infectious). The most frequent symptoms are represented by recurrent pulmonary infections from childhood. Multislice spiral dynamic CT has a major role in the study of cystic pulmonary disease and in differentiating Williams-Campbell syndrome from the other causes of cystic bronchiectasis, in which even lung function tests can give deceptive results

  12. The Role of Spiral Multidetector Dynamic CT in the Study of Williams-Campbell Syndrome

    Scioscio, V. di; Zompatori, M.; Mistura, I.; Montanari, P.; Santilli, L.; Luccaroni, R.; Sverzellati, N. [Medical Univ. of Bologna, S. Orsola-Malpighi Policlinic (Italy). Dept. of Radiology

    2006-10-15

    Williams-Campbell syndrome is a cystic bronchiectatic disease secondary to deficiency or defect of cartilaginous plates in the wall of the airways. In the literature, two main forms are suggested: congenital and acquired (post-infectious). The most frequent symptoms are represented by recurrent pulmonary infections from childhood. Multislice spiral dynamic CT has a major role in the study of cystic pulmonary disease and in differentiating Williams-Campbell syndrome from the other causes of cystic bronchiectasis, in which even lung function tests can give deceptive results.

  13. 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)

  14. 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

  15. 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 ...

  16. 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 ...

  17. CT Angiography of the Coronary Arteries

    H.Ghanaati

    2005-08-01

    Full Text Available Introduction & Background: Cardiac imaging is currently one the most rapidly advancing fields in clinical cardiology. Continuing technical innovations are expanding the applicability and usefulness of non-invasive imaging modalities such as ultrasound, nuclear imaging, positron emis-sion tomography Magnetic Resonance Imaging and most recently computed tomography (CT. In 1998, the 4-slice spiral CT scanners were introduced with a rotation time of 500ms a collimated detector width varying from 0.5 to 1.25mm. In 2002, the 16-slice spiral CT scanners were first used for coronary imag-ing. The rotation time and some of these scanners is now less than 400ms, the slice thickness varies be-tween 0.5 and 0.75mm, and a complete cardiac scan can be performed in less than 20s. In 2004, 64-slice spiral CT released into the market. Imaging of the heart requires acquisition or image reconstruction that is synchronized to the motion of the heart. Nie-man et al, irrespectively of the image quality, evalu-ated all branches with a minimal luminal diameter of 2.0mm and sensitivity and specificity of 95% and 86% respectively in comparison to angiography.

  18. 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

  19. Virtual bronchoscopy of pediatric patients based on multislice spiral CT (MSCT): initial clinical experience

    We demonstrate the benefit of the accelerated examination based on multislice spiral CT (MSCT) in the pediatric patient which has not been reported so far. Material and methods: MSCT (tube voltage 120 kV, tube current 110 mA, 4x1 mm slice thickness, 500 ms rotation time, pitch 6) was performed on a CT scanner of the latest generation (Volume Zoom, Siemens Corp., Forchheim, Germany). In total we examined 11 patients. Results: In all patients we obtained sufficient data for 3D reconstruction avoiding general anesthesia. 6/11 examinations were described to be without pathological finding. A definite diagnosis was obtained in 10 patients. Virtual bronchoscopy could avoid other invasive diagnostic examination in 8/11 patients. (orig.)

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

    龚静山; 徐坚民

    2004-01-01

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

  1. 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)

  2. Evaluation of MRU and spiral CT in the diagnosis of ureteral disease

    Objective: To discuss the diagnostic value of MRU and spiral CT in ureteral disease. Methods: MRU and SCTU were performed in 24 cases with ureteral disease including 9 cases of ureteral calculus, 5 carcinomas, 9 stenosis, and 1 malformation. Result: (1) On SCTU, the location and diameter of 9 ureteral calculus (8 radiolucent, 1 radiopaque) enlargement of renal pelvis and ureter were displayed. (2) Irregular ureteral wall, local rarefaction or discontinuity of contrast medium in ureter were detected in 5 cases of tumour in which rectums were narrowed gradually, in 7 cases of simple ureteral stenosis without thickening of the wall. (3) 1 malformation with double renal pelvis and ureter was demonstrated on MRU urinary tract dilatation at different levels clearly visualized in all the cases of impaired renal function. Conclusion (1) SCTU is superior to IVU and conventional CT by improving diagnosis of ureteral disease. (2) MR urography would be renal important information which might not be obtained by IVU

  3. Spiral CT and optimization of the modalities of the iodinated intravenous contrast material: Experimental studies in human pathology

    Spiral (or helical) CT represents the most recent improvement in the field of computed assisted tomography (CAT scan). The capabilities of this new imaging modality are much superior to these of conventional CT scanning; then result from the rapid acquisition and from the volumetric nature of the derived data set. The short time of data acquisition had made mandatory the revision of protocols for intravenous administration of iodinated contrast material. By the means of several studies, carried out on pathologic and healthy patients, we have attempted to improve knowledge in factors influencing CT attenuation values after injection of contrast material, in the aim of improving contrast administration performed during spiral CT scanning. Anatomical landmarks that we have studied till now have been liver, the pancreas, the kidney and the cervical spine. In addition, a paired based methodology has been used. The volumetric set of data derived from spiral CT scanning leads to optimal post-processing tasks, the most interesting being related to cine-display and multiplanar reformatting; both modalities have been evaluated, about the pancreas and the musculo-skeletal system respectively. Conversely, this new modality, as for other imaging modalities, is responsible for additional costs derived from restless increase in the number of images to be dealt with and from the occurrence of new tasks (in post-processing particularly). The place of spiral CT in diagnostic strategies among other modern imaging modalities should be assessed, especially with respect to Magnetic Resonance Imaging (MRI). (author)

  4. Spiral CT features of abdomen after whipple's operation

    Kim, T. H.; Lee, K. Y.; Shin, K. H.; Jung, M. H.; Park, C. M.; Cha, I. H. [Korea Univ. College of Medicine, Seoul (Korea, Republic of)

    1997-04-01

    To assess the CT features of postoperative anatomical changes, surgical complications, and patterns of tumor recurrence after Whipple's operation. 42 spiral CT scans of 31 patients who had undergone Whipple's operation were retrospectively reviewed. Postoperative diagnoses were distal CBD cancer in 13 patients, cancer of the ampulla of Vater in ten, cancer of the head of the pancreas in seven, and microcystic cystadenocarcinoma of the pancreas in one. Time intervals between surgery and CT ranged from 1 week to 5 years. CT features of postoperative anastomotic changes, surgical complications, and patterns of tumor recurrence were analyzed. Gastro- or duodeno-jejunal anastomosis was seen in 32 CT scans(74%), pancreaticojejunostomy in 27(64%), and choledochojejunostomy in 24(57%). Pneumobilia was seen in ten patients(34%). Abnormal fluid collections in the peripancreatic and perihepatic space were demonstrated in two patients who underwent CT scans within 3 weeks after operation. Other complications included wound abscess(n=2), and portal vein occlusion(n=1). The most common site of metastasis was the lymph node(n=8)(retroperitoneal:n=5; mesentery root:n=4; and celiac:n=2), followed by the liver(n=6), peritoneum(n=3), adrenal gland(n=2), and afferent loop(n=1). In three cases, there was local recurrence in the pancreatic bed. To reduce possible diagnostic errors during CT interpretation, a Knowledge of normal postoperative anatomy, common complications, and patterns of disease recurrence following Whipple's operation is important.

  5. Correlation between Dynamic Spiral-CT Enhancement Parameters and Tumor Angiogenesis in Renal Cell Carcinomas

    Jinhong Wang; Weixia Chen; Xiuhui Zhang; Pengqiu Min; Rongbo Liu; Hengxuan Yang

    2005-01-01

    OBJECTIVE To prospectively investigate the correlation between the enhancement parameters of a dynamic-CT (D-CT) scan for renal cell carcinomas (RCC) and the carcinoma tissue microvessel density (MVD) in renal cell carcinomas (RCC).METHODS Twenty-four cases of renal cell carcinoma verifyied by histopathology were scanned via dynamic-CT, followed by a whole kidney scan. Enhancement parameters were derived as follows .The slope of the contrast media uptake curve (S), area under the curve(AR), the density difference before and after tissue enhancement (△HU) and tissue blood ratio (TBR) were calculated for all lesions. Time-density curve types were ranked from the lowest to the highest of the slope of the contrast media uptake curve (S) as type A, B and C. Pathologic slides corresponding to the CT imagings were subjected to CD34 monoclonal antibodies, then were evaluated with an image analyzer to count hot spots of MVD. By using the Spearman rank correlation tests, statistical analysis was performed to determine the strength of the relationship between enhancement parameters and MVD determinations.RESULTS The carcinoma tissue MVD showed a direct correlation with the enhancement parameters of D-CT (r=0.54, r=0.62, r=0.55, r=0.64, r=0.44,P< 0.05). Moreover the S, △HU, TBR and type curves all demonstrated a strong correlation with the MVD. By analyzing the various enhancement parameters of the time-density curves, the relationship between the enhancement CT parameters corresponding to the tumor's MVD was identified.CONCLUSION A dynamic spiral-CT scan may be a helpful method as a measurement of tumor angiogenesis in vivo in RCC.

  6. 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.

  7. Reproducibility of coronary calcium quantification in repeat examinations with retrospectively ECG-gated multisection spiral CT

    High reproducibility is a key requirement for coronary calcium scoring in follow-up examinations. We investigated the inter-examination reproducibility of calcium scoring with retrospectively ECG-gated multisection spiral CT (MSCT). Fifty patients were examined twice with MSCT. Slices were reconstructed with retrospective ECG gating in the diastolic phase with 3-mm slice width and up to 125-ms temporal resolution. We calculated the Agatston score, calcium volume with and without isotropic interpolation, and calcium mass, and derived the mean and median variability. We investigated the change of variability with use of 3-mm non-overlapping and overlapping increments (2, 1.5, 1 mm). Use of overlapping increment results in considerably reduced interscan variability. We observed a minimum mean variability of 12% and a minimum median variability of 9% for the Agatston score. For volume and mass quantification we obtained a minimum mean variability of 7.5% and a minimum median variability of 5%. Multisection spiral CT enables coronary calcium quantification with high reproducibility in follow-up examinations mainly founded on image data with reduced partial-volume errors due to overlapping increment. (orig.)

  8. 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.

  9. Three-dimensional cholangio-spiral CT demonstration of a post-traumatic bile leak in a child

    Bilioma is a rare complication of traumatic liver injury, and the precise site of bile leak is often difficult to demonstrate with a non-invasive technique. We report a case of post-traumatic bile leak in a 15-year-old girl in whom spiral CT after intravenous cholangiography allowed excellent preoperative demonstration of the extent of the liver rupture and an exact location of the bile leak. We think that spiral-CT cholangiography could be an accurate, non-invasive technique to investigate the biliary system in cases of paediatric liver trauma. (orig.) (orig.)

  10. Multislice spiral CT virtual endoscopy: the clinical application in the diagnosis of vascular diseases

    Objective: To evaluate the display ability and the clinical application of multislice spiral CT virtual endoscopy (CTVE) in the diagnosis of vascular diseases. Methods: Fifty-six patients were examined by CT virtual endoscopy. 32 patients also had DSA for comparison. 18 patients were confirmed by operation (3 patients also had DSA). 9 patients with pulmonary embolism were confirmed by other examinations and treatments. Results: 56 patients showed successful CT virtual endoscopy images. CT virtual endoscopy images could clearly show the inner wall and inner structures of the vessels, mural thrombus, calcification form, stenosis of the vessels, the true and false lumina of aortic dissections, the lesion of false aneurysm, and the anatomic relationship between the lesion and surrounding structures of the normal vessels. Out of the 32 patients with vessel abnormalities on DSA, 24 patients (75%) showed the lesions on CTVE. 17 out of 18 patients with operation showed the lesions on CTVE. All 9 patients with pulmonary embolism showed the abnormalities on CTVE. Chi-square test: χ2=5.2809, P=0.071 patients showed the vascular diseases on CTVE in 56 patients (84%). Conclusion: MSCT virtual endoscopy could provide more information of the vessel by displaying the inner wall and allowing users to map the vessels in a display. It is helpful in correct diagnosis and guiding surgery

  11. Assessment of vascular invasion in pancreatic head cancer with multislice spiral CT: value of multiplanar reconstructions

    Bruegel, Melanie; Link, Thomas M.; Rummeny, Ernst J.; Lange, Peter; Dobritz, Martin [Department of Radiology, Klinikum rechts der Isar, Technische Universitaet Muenchen, Ismaninger Strasse 22, 81675, Munich (Germany); Theisen, Joerg [Department of Surgery, Klinikum rechts der Isar, Technische Universitaet Muenchen, Ismaninger Strasse 22, 81675, Munich (Germany)

    2004-07-01

    The use of multiplanar reconstructions (MPRs) generated from multislice spiral CT (MSCT) data sets in the preoperative assessment of vascular invasion in pancreatic cancer was evaluated. Forty patients underwent biphasic high-resolution MSCT prior to surgery for pancreatic head cancer. Image reconstruction included thin-slice axial, sagittal and coronal MPRs as well as an MPR perpendicular to the course of a major peripancreatic vessel in proximity to the tumor. CT criteria for vascular invasion were: (1) circumferential involvement >180 and (2) vessel narrowing. Imaging findings of 52 vessels were correlated with surgical and histopathological reports. Regarding the CT criterion circumferential involvement, vascular invasion was demonstrated on axial MPRs with a sensitivity and specificity of 58 and 97%. For the assessment with coronal and sagittal MPRs sensitivity was only 47%. Vascular invasion was recognized best on perpendicular MPRs with a sensitivity, specificity and accuracy of 74, 97 and 88%, respectively. Vessel narrowing was a less reliable CT criterion for vascular invasion, mainly due to the lower specificity of 91% obtained with each available MPR. Thin-slice MPRs oriented perpendicularly to a possibly invaded vessel exactly depict the grade of circumferential involvement and thus have the capability to improve the assessment of vascular invasion in pancreatic cancer. (orig.)

  12. Dual phase spiral CT of the pancreas : comparison of arterial and portal phase

    Chung, Myung Jin; Choi, Byung Ihn; Han, Joon Koo [Seoul National Univ. College of Medicine, Seoul (Korea, Republic of)

    1996-11-01

    To compare the images of arterial phase (AP) and portal venous phase (PVP) in the evaluation of conspicuousness of lesion and peripancreatic arterial and venous opacification in pancreatic diseases. Dual-phase spiral CT was performed in 37 patients with pancreatic adenocarcinoma and 21 patients with pancreatitis. CT scans were performed with 5 mm collimation at 1:1 pitch table feed. Images of AP and PVP were obtained at 30 and 65 seconds after administration of contrast material, was initiated. Using a grading system, images were analalysed for conspicuousness of lesion and vascular opacification(grade 1=good, grade 2=fair, grade 3=poor). In pancreatic adenocarcinoma, 35 and 36 of 37 cases showed low attenuation on AP and PVP, respectively. With regard to conspicuousness of tumour, PVP(mean grade:1.24) was superior AP(mean grade:1.43), but not significantly(p=0.0745). In arterial opacification, AP(mean grade:1.03) was significantly superior to PVP(mean grade:1.30, ; p=0.0051). In venous opacification, PVP(mean grade:1.19) was significautly to AP(mean grade:2.41;p<0.0001). In pancreatitis, 14 and 15 of 21 cases showed localized hypo-attenuating lesion indicating necrosis or fluid collection, on AP and PVP, respectively. With regard to conspicuousness of lesion, PVP(mean grade:1.61) was superior to AP(mean grade:1.81), but not significantly(p=0.1088). In arterial opacification, AP(mean grade:1.05) was significantly superior to PVP(mean grade:1.38;p=0.0180). In venous opacification, PVP(mean grade:1.10) was significantly superior to AP(mean grade:2.33;p=0.0005). For the diagnosis and staging of pancreatic disease, dual-phase spiral CT in arterial and portal venous phase may be recommendable. The portal venous phase of spiral CT seems, however, to be superior to the arterial phase because the lesion is more conspicuous and there is venous opacification.

  13. Dual phase spiral CT of the pancreas : comparison of arterial and portal phase

    To compare the images of arterial phase (AP) and portal venous phase (PVP) in the evaluation of conspicuousness of lesion and peripancreatic arterial and venous opacification in pancreatic diseases. Dual-phase spiral CT was performed in 37 patients with pancreatic adenocarcinoma and 21 patients with pancreatitis. CT scans were performed with 5 mm collimation at 1:1 pitch table feed. Images of AP and PVP were obtained at 30 and 65 seconds after administration of contrast material, was initiated. Using a grading system, images were analalysed for conspicuousness of lesion and vascular opacification(grade 1=good, grade 2=fair, grade 3=poor). In pancreatic adenocarcinoma, 35 and 36 of 37 cases showed low attenuation on AP and PVP, respectively. With regard to conspicuousness of tumour, PVP(mean grade:1.24) was superior AP(mean grade:1.43), but not significantly(p=0.0745). In arterial opacification, AP(mean grade:1.03) was significantly superior to PVP(mean grade:1.30, ; p=0.0051). In venous opacification, PVP(mean grade:1.19) was significautly to AP(mean grade:2.41;p<0.0001). In pancreatitis, 14 and 15 of 21 cases showed localized hypo-attenuating lesion indicating necrosis or fluid collection, on AP and PVP, respectively. With regard to conspicuousness of lesion, PVP(mean grade:1.61) was superior to AP(mean grade:1.81), but not significantly(p=0.1088). In arterial opacification, AP(mean grade:1.05) was significantly superior to PVP(mean grade:1.38;p=0.0180). In venous opacification, PVP(mean grade:1.10) was significantly superior to AP(mean grade:2.33;p=0.0005). For the diagnosis and staging of pancreatic disease, dual-phase spiral CT in arterial and portal venous phase may be recommendable. The portal venous phase of spiral CT seems, however, to be superior to the arterial phase because the lesion is more conspicuous and there is venous opacification

  14. Malignant focal hepatic lesions complicating underlying liver disease: dual-phase contrast-enhanced spiral CT sensitivity and specificity in orthotopic liver transplant patients

    The aim of this study was to determine the accuracy of contrast-enhanced biphasic spiral CT as a screening tool in the preoperative evaluation of orthotopic liver transplant (OLT) patients. Spiral-CT examinations were performed before liver transplantation in 53 patients. Scans were retrospectively reviewed and compared with pathologic findings in fresh-sectioned livers. When findings between spiral CT and pathology were discordant, formalized livers were reexamined with lesion-by lesion evaluation. Fresh pathologic evaluation revealed 23 liver lesions (16 HCC, 7 macro-regenerative nodules). Malignancy was identified in 13 of 53 patients (24.5%). Pre-transplantation spiral CT depicted 27 liver lesions (23 HCC, 4 macro-regenerative nodules). Malignancy was suspected in 14 patients (26.4%). In 10 of 53 (18.9%), spiral CT and pathologic evaluation were discordant. Subsequent retrospective pathologic evaluation showed malignancy in 4 additional patients. Spiral CT compared with the retrospective pathologic findings revealed 36 real-negative, 14 real-positive, 0 false-positive, and 3 false-negative patients with malignancy. Sensitivity and specificity of spiral CT in detection of malignancy was 82 and 100%, respectively. Contrast-enhanced biphasic spiral CT is an accurate technique in the evaluation of patients preceding OLT. Routine fresh-sectioned liver pathologic findings are not as sensitive as previously estimated. (orig.)

  15. Malignant focal hepatic lesions complicating underlying liver disease: dual-phase contrast-enhanced spiral CT sensitivity and specificity in orthotopic liver transplant patients

    Mortele, K.J. [Dept. of Radiology, University Hospital Gent (Belgium); Department of Radiology, Brigham and Women' s Hospital, Harvard Medical School, 75 Francis Street, Boston, MA 02115 (United States); De Keukeleire, K. [Dept. of Radiology, University Hospital Gent (Belgium); Praet, M. [Dept. of Pathology, University Hospital Gent, Gent (Belgium); Van Vlierberghe, H. [Dept. of Gastroenterology, University Hospital Gent, Gent (Belgium); Hemptinne, B. de [Dept. of Surgery, University Hospital Gent, Gent (Belgium); Ros, P.R. [Department of Radiology, Brigham and Women' s Hospital, Harvard Medical School, 75 Francis Street, Boston, MA 02115 (United States)

    2001-09-01

    The aim of this study was to determine the accuracy of contrast-enhanced biphasic spiral CT as a screening tool in the preoperative evaluation of orthotopic liver transplant (OLT) patients. Spiral-CT examinations were performed before liver transplantation in 53 patients. Scans were retrospectively reviewed and compared with pathologic findings in fresh-sectioned livers. When findings between spiral CT and pathology were discordant, formalized livers were reexamined with lesion-by lesion evaluation. Fresh pathologic evaluation revealed 23 liver lesions (16 HCC, 7 macro-regenerative nodules). Malignancy was identified in 13 of 53 patients (24.5%). Pre-transplantation spiral CT depicted 27 liver lesions (23 HCC, 4 macro-regenerative nodules). Malignancy was suspected in 14 patients (26.4%). In 10 of 53 (18.9%), spiral CT and pathologic evaluation were discordant. Subsequent retrospective pathologic evaluation showed malignancy in 4 additional patients. Spiral CT compared with the retrospective pathologic findings revealed 36 real-negative, 14 real-positive, 0 false-positive, and 3 false-negative patients with malignancy. Sensitivity and specificity of spiral CT in detection of malignancy was 82 and 100%, respectively. Contrast-enhanced biphasic spiral CT is an accurate technique in the evaluation of patients preceding OLT. Routine fresh-sectioned liver pathologic findings are not as sensitive as previously estimated. (orig.)

  16. Measurements of computed tomography dose index for axial and spiral CT scanners

    The energy deposited in the patient by the rotating x-ray beam in computed tomography produces more uniform absorbed dose values within the section of imaged tissue than those produced in conventional radiological procedures. The dose values within a specific section are determined by factors such as voltage, current, scan field, rotation angle, filtration, collimation, and section thickness and spacing. This study is a part of extensive project, aiming to investigate practice of computed tomography at various hospitals and to implement a Reference Dose Levels (RDLs) to routine CT examinations in Egypt. The dosimetric quantities proposed in the European Guidelines (EG) for CT are weighted computed tomography dose index (CTDIw) for a single slice and dose-length product (DLP) for a complete examination. Patient-related data as well as technical parameters for head, chest, abdomen and pelvis examinations were collected for seven CT scanners in public and private hospitals.Dose measurements were performed for both axial and spiral models for a range of CT examinations using CT dosimetry head and body phantoms, and ion chamber designed for CT dosimetry. The determined CTDIw and DLP values were compared with the European Commission reference dose levels (ECRDLs) and also with some international survey results. Mean values of CTDIw had a range of 36-69 m Gy with average 55 m Gy for head, and 11-35 mGy with average 23 mGy for chest, abdomen and pelvis examinations. The current reference CTDIw values are 60 m Gy for adult head and 25 m Gy for adult Abdomen

  17. The usefulness of levin tube inserted drip infusion spiral CT: comparison with conventional method in subtotal gastrectomy patients

    Park, Young Jin; Kim, Young Hwan; Yoon, Jung Hee; Cha, Soon Joo; Kim, Jeong Sook [Sanggye Paik Hospital, Seoul (Korea, Republic of); Kim, Sung Rok; Hur, Gham; Rhim, Hyun Chul [Hanyang University Hospital, Seoul (Korea, Republic of)

    1998-04-01

    The purpose of this study is to access the usefulness of newly designed Levin tube inserted drip infusion spiral CT for the evaluation of remnant stomach and anastomosis site in patients who have undergone subtotal gastrectomy for stomach cancer. A new technique named Levin tube inserted drip infusion spiral CT was used to prospectively study 23 patients. A 16Fr Levin tube was inserted into the remnant stomach; 500 ml of tap water was drip infused just before CT scanning and an additional 500 ml of water was infused during IV contrast injection. Water was infused by gravity, using a water bottle suspended at a height of 90 cm (Group A). The 31 patients who underwent conventional spiral CT scanning immediately after the divided ingestion of 900 ml diluted gastrografin were selected as a control group (Group B). The anatomic delineation of the anastomosis site was graded by two radiologists as excellent (3), good(2), fair (1) or poor (0). To evaluate the degree of distension, the maximal diameters of remnant stomach and the anastomosis site, and the thickness of the stomach wall, were also measured. In patients who had undergone subtobal gastrectomy, Levin tube inserted drip infusion spiral CT showed excellent anatomic delineation of the site of anastomosis and remnant stomach. We found that because it increases the distension of remnant stomach and the anastomosis site, this technique is effective for the evaluation of postoperative stomach. (author). 10 refs., 2 tabs., 3 figs.

  18. 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)

  19. Use of spiral CT angiography to judge central pulmonary vascular involvement from lung cancer

    Objective: To evaluate the accuracy of spiral CT angiography (SCTA) in judging central pulmonary vascular involvement from lung cancer located in the hilum and correlate the resultant images with pathologic and surgical findings. Methods: SCTA was done in 33 patients who were preoperatively diagnosed as having lung carcinoma located in the hilum. Contrast medium was injected at a rate of 3 ml/sec with a power injector. The delay time was from 20 to 25 seconds. The pitch was 1 with 3 mm-collimation. Images of central pulmonary arteries and veins were reconstructed with shaded surface display (SSD), maximum intensity projection (MIP), curved planar reformation (CPR), and multi-planar reformation (MPR). Then the relation between tumor and vessels was assessed prospectively on both 3 mm interval axial CT and SCTA images with comparison to subsequent pathologic or surgical findings. Results: (1) In showing the integrity of central pulmonary arteries and veins, images reconstructed by different ways of SCTA had different strong and weak points. (2) The grading standard in this study, with which the relation between vessels and tumor was judged, reflected the basic and common characters of central pulmonary vascular involvement by tumor located in the hilum. compared with axial CT images, SCTA was more accurate in judging the relation between central pulmonary vessels and tumor, and the correlation of SCTA imaging features with pathological patterns and surgical findings was better than that of axial CT images, P < 0.05 and P < 0.0001, respectively. Conclusion: It was feasible to show the relation between central pulmonary vessel and lung cancer located in the hilum with SCTA. And the accuracy of judging the vascular involvement with SCTA was higher than that with axial CT

  20. Pulmonary emphysema quantitation with Computed Tomography. Comparison between the visual score with high resolution CT, expiratory density mask with spiral CT and lung function studies

    CT is the most accurate method to detect pulmonary emphysema in vivo. They compared prospectively two different methods for emphysema quantitation in 5 normal volunteers and 20 consecutive patients with chronic obstructive pulmonary disease (COPD). All subjects were submitted to function tests and HRCT; three scans were acquired at preselected levels during inspiration. The type and extent of pulmonary emphysema were defined by two independent observers under blind conditions. Disagreements were subsequently settled by consent. All subjects were also examined with expiratory spiral CT using a density mask program, at two different cut-off levels (-850,-900 HU). Visual score and expiratory spiral density mask values (-850 HU) were significantly correlated (r = 0.86), but the visual extent of emphysema was always higher than shown by expiratory spiral CT. The emphysema extent assessed with both CT methods correlated with the function result of expiratory airflow obstruction and gas diffusion impairment (visual score versus forced expiratory volume in one second: r = -0.81, versus single breath carbon monoxide diffusion: r = -0.78. Spiral expiratory density mask -850 HU versus forced expiratory volume in one second: r = -0.85 versus single breath carbon monoxide diffusion: r = -0.77). When -900 HU was used as the cut-off value for the expiratory density mask, the correlation with single breath carbon monoxide diffusion worsened (r = -0.56). Visual score and expiratory density mask -850 HU gave similar results and permitted COPD patients to be clearly distinguished from normal controls (p < 0.01). They believe the true residual volume should lie somewhere in between the CT value and the function results with the helium dilution technique and conclude that the extent of pulmonary emphysema can be confidently assessed with CT methods. Finally, the simple visual score may be as reliable as such highly sophisticated new methods as the spiral expiratory density mask

  1. Spiral hydro-CT of the pancreas in the thin-slice method; Hydrospiral-CT des Pankreas in Duennschichttechnik

    Richter, G.M. [Abt. fuer Radiodiagnostik, Radiologische Universitaetsklinik Heidelberg (Germany); Simon, C. [Abt. fuer Radiodiagnostik, Radiologische Universitaetsklinik Heidelberg (Germany)]|[Abt. Allgemeine Chirurgie, Chirurgische Universitaetsklinik Heidelberg (Germany); Hoffmann, V. [Abt. fuer Radiodiagnostik, Radiologische Universitaetsklinik Heidelberg (Germany); DeBernardinis, M. [Abt. fuer Radiodiagnostik, Radiologische Universitaetsklinik Heidelberg (Germany); Seelos, R. [Abt. Allgemeine Chirurgie, Chirurgische Universitaetsklinik Heidelberg (Germany); Senninger, N. [Abt. Allgemeine Chirurgie, Chirurgische Universitaetsklinik Heidelberg (Germany); Kauffmann, G.W. [Abt. fuer Radiodiagnostik, Radiologische Universitaetsklinik Heidelberg (Germany)

    1996-05-01

    In an open prospective study, 151 patients with a suspected pancreatic neoplasm based on clinical, laboratory or other imaging data were examined between May 94 and October 95. Our newly developed Hydro-CT methodology included intravenous injection of 40 mg N-butylscopolaminium bromide (Buscopan) for intestinal paralysis, gastric and duodenal wall distension by oral administration of an average of 1.5 l warm tap water, 30 RAO patient positioning, an individualized contrast injection technique as determined beforehand by time-to-peak measurement in the portal vein and thin-slice spiral CT (3 mm increment, 6 mm table feed and 3 mm secondary reconstruction). A detailed evaluation form was used to assess (1) tumor detection rate, (2) differentiation of malignant versus benign disease, (3) differential diagnosis, and (4) accuracy of assessment of resectability by identification of infiltration into adjacent organs and vessel structures relevant for resectability such as splenic, superior mesenteric, portal vein and celiac trunk, superior mesenteric, splenic and hepatic arteries. As the gold standard for positive tumor detection surgery and microscopic diagnosis were used, and for negative tumor detection an event-free survival of 6 months. Almost all examinations were well tolerated. In only 4% was on-site administration of a gastric tube required because of vomiting. In 2% of the patients a slight allergic reaction to be contrast medium was seen. The prevalence of a pancreatic neoplasm was 38%. In tumor detection Hydro-CT reached an overall accuracy of 97.4% with a sensitivity of 100% and a specificity of 95.9%. In the differentiation of benign versus malignant disease Hydro-CT reached an overall accuracy of 89.7% with a sensitivity of 92.5% and a specificity of 83.3%. The prevalence of a pancreatic carcinoma was 24%; 4% other malignant tumors were found (distal common bile duct carcinoma, cystadenocarcinoma). (orig./MG) [Deutsch] Von Mai 1994 bis Oktober 1995 wurden

  2. [Small renal cell carcinoma (≤ 4 cm): enhancement patterns on triphasic spiral CT].

    Rebonato, Alberto; Pierotti, Luisa; Barberini, Francesco; Rosi, Giovanni; Macarini, Luca; Scialpi, Michele

    2012-11-01

    The aim of this study was to define enhancement patterns of small renal cell carcinoma (RCC) (≤4 cm) by triphasic spiral CT. In 24 patients with RCC, hypervascularity and hypovascularity were identified in 12 and 12 RO, respectively, in the cortico-medullary phase (CMP). Hypervascular RCC showed increased density in the CMP (170,7±46,3 UH) and a gradual wash-out in the nephrographic phase (NP) (152,5±41 UH) and pielographic phase (PF) (99,2±38 UH). Hypovascular RCC showed increased density in the CMP (52,9±24,7 UH) and a gradual wash-out in NP (64,5±16,9 UH) and PP phases (55,0±17,3 UH). PMID:23096734

  3. Reduced volume of contrast media; effect on vascular opacification and image quality in spiral CT of the chest

    To evaluate the effect of reduced volume of contrast media on vascular opacification and image quality in spiral CT of the chest. Sixty patients referred for chest CT were examined with spiral CT with 60ml (n=30) or 90ml(n=30) of 30% ionic contrast media(Rayvist 300r, Schering, Germany) alternately. Injection rate of each group was as follows; 2.0ml/sec for 20 seconds followed by 1.0ml/sec for 20 seconds in 60ml group and 2.0ml/sec for 45 seconds in 90ml group. Twenty-five seconds scanning delay was employed. For the objective comparison of vascular opacification, CT numbers were measured at superior vena cava, ascending and descending aorta, right and left pulmonary artery, left atrium, and inferior vena cava. For the subjective comparison three radiologists scored the grade of vascular opacification and image quality blindly and independently. All data were analyzed statistically. The mean values of measured CT numbers in 90ml group were higher than those in 60ml group (p<.05) at the same level. The overall mean score of vascular opacification in 90ml group was 2.86, and 2.31 in 60ml group(p<.0001). In the overall mean score of image quality, there was no statistically significant difference between 90ml group(2.46) and 60ml group(2.40). Although there is some degradation of vascular opacification in 60ml group, overall image quality is not degraded. Therefore, 60ml of contrast media can be used in spiral CT of the chest without degradation of overall image quality except in spiral CT angiography

  4. 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)

  5. Evaluation of image quality and dose in renal colic: comparison of different spiral-CT protocols

    Rimondini, A.; Mucelli, R.P.; Dalla Palma, L. [Dept. of Radiology, University of Trieste (Italy); De Denaro, M.; Bregant, P. [Dept. of Medical Physics, Ospedale Maggiore, Trieste (Italy)

    2001-07-01

    The aim of this study was to test different technical spiral-CT parameters to obtain optimal image quality with reduced X-ray dose. Images were acquired with a spiral-CT system Philips Tomoscan AVE1, using 250 mA, 120 kV, and 1-s rotational time. Three protocols were tested: protocol A with 5-mm thickness, pitch 1.6, slice reconstruction every 2.5 mm; protocol B with 3-mm thickness, pitch 1.6, slice reconstruction every 1.5 mm; and protocol C with 3-mm thickness, pitch 2, slice reconstruction every 1.5 mm. Two phantoms were employed to evaluate the image quality. Axial images were acquired, then sagittal and coronal images were reconstructed. Finally, the absorbed X-ray dose for each protocol was measured. Regarding image quality, 5-mm-thick images (protocol A) showed greater spatial resolution and lower noise compared with 3-mm-thick images (protocols B and C) on the axial plane; 3-mm reconstructed sagittal and coronal images (protocols B and C) showed an improved image quality compared with 5-mm reformatted images (protocol A). Concerning X-ray dose, the mean dose was: protocol A 19.6{+-}0.8 mGy; protocol B 14.4{+-}0.6 mGy; protocol C 12.5{+-}1.0 mGy. Our study supports the use of thin slices (3 mm) combined with pitch of 1.6 or 2 in renal colic for X-ray dose reduction to the patient and good image quality. (orig.)

  6. Evaluation of 10 mAs and low-contrast CT image optimization based on the multifractal spectrum in brain of infant

    Objective: To analyze scanned image optimization based on the multifractal soectrum and image fractal algorithm of 64-slice spiral CT in brain of infant. Methods: The image data of Toshiba Aquilion 64-slice CT scanning using 10 mAs were imported to image processing toolboxs of Matlab 7.1. The evaluation of multifractal spectrum and image denosing were performed, and compared with image quality of conventional low-dose CT using 50 mAs. Results: The low-contrast scanned image used 10 mAs is the valueless medical image because of serious noise. Image denoise based on the fractal model had superior characteristic of image detail preserving and better contrast-to-noise ratio(CNR). There existed a group difference in the score of image quality between the rude imaging noise and optimized image based on the multifractal spectrum algorithm, though the score was still significantly lower than the normal dosage scanned image (F=38.85, P<0.01). The group difference was also manifested the image quality of infants can achieve basically the request of clinical diagnosis by suitable model denoising algorithm. Conclusions: Image denoising based on the multifractal spectrum model can be used on the low-dose and low-contrast CT image optimization. It improved the CNR of the pathological region. The radiation dose of CT scanning in infants would be declined significantly by its further application in the future. (authors)

  7. 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

  8. Effect of the degree of sternal depression on the cardiac rotation in pectus excavatum: evaluation with spiral CT

    Objective: To evaluate the effects of the degree of sternal depression on the cardiac rotation in pectus excavatum by using spiral CT. Methods: Spiral CT features of 32 patients with surgically corrected pectus excavatum were retrospectively reviewed. They included 27 males and 5 females ranging in age from 6 months to 17 years (mean, 6.3 years). Analysis was based on relationship among the degree of sternal depression, CT depression index, cardiac rotation angle, and PV angle. Results: 32 cases of pectus excavatum presented the sternal depression (21 ± 7) mm, CT depression index 2.9 ± 1.8, cardiac rotation angle (55.9 ± 9.8) degree, and PV angle (49.8 ± 14.0) degree, respectively. The sternal depression (17 mm) in cases with CT depression index less than 2.4 was smaller than those with CT depression index 2.4-2.9 (21 mm) and CT depression index larger than 2.9 (27 mm) (F 5.39, P<0.01). Cardiac rotation angle (49.7 degree) in cases with CT depression index less than 2.4 was smaller than those with CT depression index 2.4-2.9 (55.5 degree) and CT depression index larger than 2.9 (66.9 degree) (F=7.44, P<0.01). PV angle (58.7 degree) in cases with CT depression index less than 2.4 was larger than those with CT depression index 2.4-2.9 (46.5 degree) and CT depression index more than 2.9 (42.4 degree) ( F=3.33, P<0.05). Cardiac rotation angle of pectus excavatum had positive correlation with the CT depression index (γ=0.73, P<0.01). Conclusion: Spiral CT is a better tool for revealing chest deformity and corresponding cardiac rotation. The degree of sternal depression in pectus excavatum directly influences the cardiac rotation, and they had positive correlation. (authors)

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

    Jing-Shan Gong; Jian-Min Xu

    2004-01-01

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

  10. Unenhanced spiral CT in acute ureteral colic: a replacement for excretory urography?

    To compare the usefulness of unenhanced spiral CT (UCT) with that of excretory urography (EU) in patients with acute flank pain. Thirty patients presenting with acute flank pain underwent both UCT and EU. Both techniques were used to determine the presence, size, and location of urinary stone, and the presence or absence of secondary signs was also evaluated. The existence of ureteral stone was confirmed by its removal or spontaneous passage during follow-up. The absence of a stone was determined on the basis of the clinical and radiological evidence. Twenty-one of the 30 patients had one or more ureteral stones and nine had no stone. CT depicted 22 of 23 calculi in the 21 patients with a stone, and no calculus in all nine without a stone. The sensitivity and specificity of UCT were 96% and 100%, respectively. EU disclosed 14 calculi in the 21 patients with a stone and no calculus in eight of the nine without a stone. UCT and EU demonstrated secondary signs of ureterolithiasis in 15 and 17 patients, respectively. For the evaluation of patients with acute flank pain, UCT is an excellent modality with high sensitivity and specificity. In near future it may replace EU

  11. Measurement and analysis of cardiopulmonary vascular in Lanzhou healthy adults with multislice spiral CT

    Objective: To constitute a normal standard of cardiopulmonary vascular diameter and size of normal adult in Lanzhou, and to compared with the other's data reported in the previous bibliography by measuring diameter and area of cardiopulmonary artery lumen of the healthy adults in Lanzhou with multislice spiral CT (MSCT). Methods: Three hundred Lanzhou adults with no cardiopulmonary disease were equally assigned to 3 groups according to their age (A group: 18-39 years, B group: 40-60 years, C group: 61-80 years; 50 females and 50 males in each group). CT data were acquired at the end of deep inspiration phase and measurements were done on 3D reconstruction image with precise landmarks. All the results were statistically analyzed. Results: The diameters and areas of the main pulmonary artery left pulmonary artery right pulmonary artery ascending aorta and descending aorta differed significantly among the 3 groups (P<0.05). In groups B and C, there were significant differences in diameters and areas of pulmonary artery left pulmonary artery and right pulmonary between different genders (P<0.05). Conclusion: Imaging standard is provided for Lanzhou adult in early diagnosis of cardiopulmonary disease. The diameters and areas of main pulmonary artery left pulmonary artery and right pulmonary artery of Lanzhou healthy adults are different from that of other regions. It may be related to the geographical environment and the state of air pollution in Lanzhou. (authors)

  12. 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

  13. Image Quality of 3rd Generation Spiral Cranial Dual-Source CT in Combination with an Advanced Model Iterative Reconstruction Technique: A Prospective Intra-Individual Comparison Study to Standard Sequential Cranial CT Using Identical Radiation Dose

    Wenz, Holger; Máté E Maros; Meyer, Mathias; Förster, Alex; Haubenreisser, Holger; Kurth, Stefan; Schoenberg, Stefan O.; Flohr, Thomas; Leidecker, Christianne; Groden, Christoph; Scharf, Johann; HENZLER, THOMAS

    2015-01-01

    Objectives To prospectively intra-individually compare image quality of a 3rd generation Dual-Source-CT (DSCT) spiral cranial CT (cCT) to a sequential 4-slice Multi-Slice-CT (MSCT) while maintaining identical intra-individual radiation dose levels. Methods 35 patients, who had a non-contrast enhanced sequential cCT examination on a 4-slice MDCT within the past 12 months, underwent a spiral cCT scan on a 3rd generation DSCT. CTDIvol identical to initial 4-slice MDCT was applied. Data was recon...

  14. 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

  15. SPIO-MR imaging versus double-phase spiral CT in detecting malignant lesions of the liver

    Purpose: To assess the diagnostic performance of superparamagnetic iron oxide MR (SPIO-MR) imaging compared with double-phase spiral CT in detecting liver metastases and hepatocellular carcinoma. Material and Methods: Thirty-eight patients with a total of 144 malignant lesions of the liver were examined by CT and SPIO-MR. After definition of a gold standard by a panel of experts, the patient images were randomized and presented to a blinded jury of 5 independent observers whose task was to identify as many lesions as possible. The results were tested for statistical significance using multifactorial analysis of variance (α=5%). Results: SPIO-MR produced the highest detection rate and was significantly superior (p<0.05) to unenhanced MR imaging and double spiral-phase contrast-enhanced CT (DPS-CECT). Maximum performance in DPS-CECT was obtained during the portal venous contrast phase but was significantly inferior to SPIO-MR imaging. The scores for unenhanced CT and unenhanced MR were significantly lower than for the corresponding enhanced procedures. SPIO-MR imaging produced a higher incidence of false-positive findings (n=39). Conclusion: SPIO-MR produced a significantly better detection rate for malignant focal liver lesions compared with double-phase spiral DPS-CECT but was associated with a higher rate of false-positive findings. (orig.)

  16. SPIO-MR imaging versus double-phase spiral CT in detecting malignant lesions of the liver

    To assess the diagnostic performance of superparamagnetic iron oxide MR (SPIO-MR) imaging compared with double-phase spiral CT in detecting liver metastases and hepatocellular carcinoma. Thirty-eight patients with a total of 144 malignant lesions of the liver were examined by CT and SPIO-MR. After definition of a gold standard by a panel of experts, the patient images were randomized and presented to a blinded jury of 5 independent observers whose task was to identify as many lesions as possible. The results were tested for statistical significance using multifactorial analysis of variance (alpha=5%). SPIO-MR produced the highest detection rate and was significantly superior (p<0.05) to unenhanced MR imaging and double spiral-phase contrast-enhanced CT (DPS-CECT). Maximum performance in DPS-CECT was obtained during the portal venous contrast phase but was significantly inferior to SPIO-MR imaging. The scores for unenhanced CT and unenhanced MR were significantly lower than for the corresponding enhanced procedures. SPIO-MR imaging produced a higher incidence of false-positive findings (n=39). SPIO-MR produced a significantly better detection rate for malignant focal liver lesions compared with double-phase spiral DPS-CECT but was associated with a higher rate of false-positive findings

  17. The usefulness of three-dimensional imaging with spiral CT in the evaluation of upper airway stenosis

    To assess the usefulness of three-dimensional (3D) spiral CT imaging in patients with upper airway stenosis. We performed 3D spiral CT imagings in ten patients in whom upper airway stenosis was clinically suspected. Eight of these patients had upper airway stenosis caused by intubation or tracheostomy (n-6), tuberculosis (n=1), or extrinsic compression by a thyroid mass (n=1). Spiral CT scanning (30-second continuous exposure and 90-mm length) was performed with a table speed of 3mm/sec and a section thickness of 3mm. The selected starting point was the epiglottis. The resulting data were reformatted by multiplanar reformation (MPR) and shaded surface display (SSD) with peeling after reconstruction of 2mm interval. In the evaluation of location and extent of stenosis, we compared fidings of 3D imaging with those of baseline axial images (n=10), endoscopy (n=9) and operation (n=4). The locations of stenosis in eight patients were as follows;tracheostoma (n=4), subglottic region (n=3), and larynx (n=1). In all eight, 3D imaging demonstrated the location and extent of stenosis, which exactly correlated with endoscopic and operative findings. In one patient, however, another stenotic area in the tracheal bifurcation was not discovered because this lesion was not included in the field of CT scan. In two patients, the diagnosis on 3D images of no 'stenosis' was comfirmed by clinical findings or operation. No differences in diagnostic accuracy were noted between axial images, MPR, and SSD when evalvating the location and extent of stenosis; vertical extent was shown more easily by 3D imaging than by axial images, however. 3D imaging with spiral CT may be an useful adjunctive method in the evaluation of upper airway stenosis with variable causes

  18. The usefulness of three-dimensional imaging with spiral CT in the evaluation of upper airway stenosis

    Jang, Won Ho; Yoon, Dae Young; Bae, Sang Hoon; Rho, Young Soo; Jung, Yin Gyo [Hallym Univ. College of Medicine, Seoul (Korea, Republic of)

    1996-01-01

    To assess the usefulness of three-dimensional (3D) spiral CT imaging in patients with upper airway stenosis. We performed 3D spiral CT imagings in ten patients in whom upper airway stenosis was clinically suspected. Eight of these patients had upper airway stenosis caused by intubation or tracheostomy (n-6), tuberculosis (n=1), or extrinsic compression by a thyroid mass (n=1). Spiral CT scanning (30-second continuous exposure and 90-mm length) was performed with a table speed of 3mm/sec and a section thickness of 3mm. The selected starting point was the epiglottis. The resulting data were reformatted by multiplanar reformation (MPR) and shaded surface display (SSD) with peeling after reconstruction of 2mm interval. In the evaluation of location and extent of stenosis, we compared fidings of 3D imaging with those of baseline axial images (n=10), endoscopy (n=9) and operation (n=4). The locations of stenosis in eight patients were as follows;tracheostoma (n=4), subglottic region (n=3), and larynx (n=1). In all eight, 3D imaging demonstrated the location and extent of stenosis, which exactly correlated with endoscopic and operative findings. In one patient, however, another stenotic area in the tracheal bifurcation was not discovered because this lesion was not included in the field of CT scan. In two patients, the diagnosis on 3D images of no 'stenosis' was comfirmed by clinical findings or operation. No differences in diagnostic accuracy were noted between axial images, MPR, and SSD when evalvating the location and extent of stenosis; vertical extent was shown more easily by 3D imaging than by axial images, however. 3D imaging with spiral CT may be an useful adjunctive method in the evaluation of upper airway stenosis with variable causes.

  19. 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

  20. Shallow and deep breath lung tumor volume as estimated by spiral volumetric CT in comparison to standard axial CT using virtual simulation

    Purpose/Objective: In order to assess an individual patient tumor volume (TV) margins that are sufficient to design a beam-eye-view (BEW) conformal portal, the radiographic extent of gross tumor volume (GTV) dimensions and its fluctuation with breathing are measured by fast spiral CT scanning of patients treated for Stage II, III lung cancers using 5-6 field multi-collimated conformal beams. Materials and Methods: Over the course of conformal radiotherapy for lung cancer, a full thorax CT scans of the patient were taken by conventional axial CT scanning with patients immobilized in the treatment position and breathing normally. Patient(s) with good pulmonary function test (PFT) status were selected to perform deep breathing and re-scanned by fast spiral techniques in order to re-acquire the tomographic variation in the (GTV) with breathing. A Picker spiral ZAP-100 software running on the AQSim-PQ-2000 was used with a variable helical pitch of 1.0, 1.5 and 2.0. The variable pitch spirals were limited to tumor bed, diaphragm and lung apex area for measurements. Effect of breathing motion along x,y,z direction were then assessed for each beam-eye-view portal as seen in digitally reconstructed radiography (DRR) at the treated gantry angle. Results: Comparison of axial and spiral scans shows the progression of lung and diaphram motion with breathing can be gauged better in spiral scans. The movement of the diaphragm during shallow breathing has been found to be 2-3cm by measuring the distance between the most inferior and superior slices where diaphragm is present. The variation of the tumor dimensions along AP/PA and lateral direction seems to be less sensitive to breathing than those along inferior-superior direction. Conclusion: The fast spiral CT scanning is sensitive to patient lung motion and can be used to determine the fluctuations of the gross tumor volume with breathing. The extent of the fluctuation is location dependent and increases as one moves from the

  1. CT-guided needle biopsy in pulmonary and mediastinal masses. Influence of spiral CT and different biopsy needles on the results; CT-gestuetzte Nadelbiopsie bei pulmonalen und mediastinalen Raumforderungen. Der Einfluss der Spiral-CT und unterschiedlicher Biopsienadeln auf die Ergebnisse

    Rotte, K.H. [Robert-Roessle-Klinik, Klinikum Rudolf Virchow, Freie Univ. Berlin, Berlin-Buch (Germany)

    1995-05-01

    The efficacy of percutaneous CT-guided needle biopsies was investigated in 68 patients with pulmonary lesions and in 65 patients with mediastinal masses. In comparison with conventional multisectional CT, the time needed for the localization of the needle tip could be reduced by use of spiral CT. Comparing aspiration and cutting biopsy needle we achieved a higher accuracy of 94% in case of mediastinal masses and of 90% by using cutting needles. The rate of complications, such as pneumothoraces, is relatively low. (orig.) [Deutsch] Der Wert der perkutanen CT-gestuetzten Nadelbiopsie wurde bei 68 Patienten mit pulmonalen Herden und bei 65 Patienten mit mediastinalen Raumforderungen ueberprueft. Die Spiral-CT fuehrte im Vergleich mit der konventionellen Mehrschnitt-Computertomographie zu einer Erleichterung der Lokalisierung der Nadelspitze und zu einer Verkuerzung der hierfuer benoetigten Zeit. Die Punktionsergebnisse konnten mit der Spiral-CT nicht signifikant verbessert werden. Der Vergleich von CT-gezielten Schneidbiopsien mit Aspirationsbiopsien zeigte mit einer Treffsicherheit von 94% bei den mediastinalen Raumforderungen und von 90% bei den pulmonalen Herden eine Ueberlegenheit der Schneidbiopsie. Die Komplikationsrate war gering. (orig.)

  2. 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)

  3. Comparison of fan-beam, cone-beam, and spiral scan reconstruction in x-ray micro-CT

    Sasov, Alexander

    2001-06-01

    We developed and tested reconstruction software packages for different algorithms: fan-beam, cone-beam (Feldkamp) and spiral (helical) scans. All algorithms were applied to different simulations as well as to the real datasets from the commercial micro-CT instruments. From the results of testing a number of strong and weak points at different approaches was found. Several examples from the different application areas (bone microstructure, industrial applications) show typical reconstruction artifacts with different algorithms.

  4. 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.

  5. 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)

  6. Multiplanar spiral CT enterography in patients with Crohn's disease using a negative oral contrast material: initial results of a noninvasive imaging approach

    Reittner, Pia; Goritschnig, Toria; Doerfler, Otto [Department of Radiology, Karl Franzens Medical School and University Hospital Graz, Auenbruggerplatz 9, 8036 Graz (Austria); Petritsch, Wolfgang; Hinterleitner, Thomas [Department of Internal Medicine, Karl Franzens Medical School and University Hospital Graz, Auenbruggerplatz 9, 8036 Graz (Austria); Preidler, Klaus W.; Szolar, Dieter H. [Diagnostikum Graz Sued West, Weblinger Guertel 25, 8054 Graz (Austria)

    2002-09-01

    The aim of this study was to prospectively define the role of multiplanar spiral CT enterography with a new negative oral contrast material for noninvasive assessment of the small bowel in patients with Crohn's disease. Thirty patients with established Crohn's disease prospectively underwent spiral CT enterography at 45-60 min after distension of the small bowel with 1400 ml of a negative oral contrast material (Mucofalk water enema). Spiral CT scans were obtained 50 s after administration of intravenous contrast material with the following parameters: 5-mm collimation; 7.5-mm/s table feed; and 3-mm reconstruction interval. The adequacy of bowel opacification, luminal distension, and the contribution of two-dimensional multiplanar reformatted imaging were assessed by two observers. Spiral CT imaging findings were compared with results of enteroclysis as well as endoscopic and histological findings in all patients. Spiral CT enterography with Mucofalk water enema was well tolerated in 29 of 30 patients. Findings on spiral CT enterography were comparable with those of barium studies in 25 of 30 patients, superior to those on barium studies in 4 patients, and inferior in 1 patient (p<0.05). The addition of multiplanar reformatted images to axial spiral CT scans significantly improved observers' confidence in image interpretation (p<0.05) but did not reveal additional abnormalities. Multiplanar spiral CT enterography with Mucofalk excellently provides information in patients with Crohn's disease. This technique accurately depicts the level of small bowel obstruction and the extent of inflammatory small bowel disease and its extraluminal complications. (orig.)

  7. Multiplanar spiral CT enterography in patients with Crohn's disease using a negative oral contrast material: initial results of a noninvasive imaging approach

    The aim of this study was to prospectively define the role of multiplanar spiral CT enterography with a new negative oral contrast material for noninvasive assessment of the small bowel in patients with Crohn's disease. Thirty patients with established Crohn's disease prospectively underwent spiral CT enterography at 45-60 min after distension of the small bowel with 1400 ml of a negative oral contrast material (Mucofalk water enema). Spiral CT scans were obtained 50 s after administration of intravenous contrast material with the following parameters: 5-mm collimation; 7.5-mm/s table feed; and 3-mm reconstruction interval. The adequacy of bowel opacification, luminal distension, and the contribution of two-dimensional multiplanar reformatted imaging were assessed by two observers. Spiral CT imaging findings were compared with results of enteroclysis as well as endoscopic and histological findings in all patients. Spiral CT enterography with Mucofalk water enema was well tolerated in 29 of 30 patients. Findings on spiral CT enterography were comparable with those of barium studies in 25 of 30 patients, superior to those on barium studies in 4 patients, and inferior in 1 patient (p<0.05). The addition of multiplanar reformatted images to axial spiral CT scans significantly improved observers' confidence in image interpretation (p<0.05) but did not reveal additional abnormalities. Multiplanar spiral CT enterography with Mucofalk excellently provides information in patients with Crohn's disease. This technique accurately depicts the level of small bowel obstruction and the extent of inflammatory small bowel disease and its extraluminal complications. (orig.)

  8. Image Quality of 3rd Generation Spiral Cranial Dual-Source CT in Combination with an Advanced Model Iterative Reconstruction Technique: A Prospective Intra-Individual Comparison Study to Standard Sequential Cranial CT Using Identical Radiation Dose.

    Holger Wenz

    Full Text Available To prospectively intra-individually compare image quality of a 3rd generation Dual-Source-CT (DSCT spiral cranial CT (cCT to a sequential 4-slice Multi-Slice-CT (MSCT while maintaining identical intra-individual radiation dose levels.35 patients, who had a non-contrast enhanced sequential cCT examination on a 4-slice MDCT within the past 12 months, underwent a spiral cCT scan on a 3rd generation DSCT. CTDIvol identical to initial 4-slice MDCT was applied. Data was reconstructed using filtered backward projection (FBP and 3rd-generation iterative reconstruction (IR algorithm at 5 different IR strength levels. Two neuroradiologists independently evaluated subjective image quality using a 4-point Likert-scale and objective image quality was assessed in white matter and nucleus caudatus with signal-to-noise ratios (SNR being subsequently calculated.Subjective image quality of all spiral cCT datasets was rated significantly higher compared to the 4-slice MDCT sequential acquisitions (p<0.05. Mean SNR was significantly higher in all spiral compared to sequential cCT datasets with mean SNR improvement of 61.65% (p*Bonferroni0.05<0.0024. Subjective image quality improved with increasing IR levels.Combination of 3rd-generation DSCT spiral cCT with an advanced model IR technique significantly improves subjective and objective image quality compared to a standard sequential cCT acquisition acquired at identical dose levels.

  9. Assessment of Hemodynamics in a Rat Model of Liver Cirrhosis with Precancerous Lesions Using Multislice Spiral CT Perfusion Imaging

    Guolin Ma

    2013-01-01

    Full Text Available Rationale and Objectives. To develop an optimal scanning protocol for multislice spiral CT perfusion (CTP imaging to evaluate hemodynamic changes in liver cirrhosis with diethylnitrosamine- (DEN- induced precancerous lesions. Materials and Methods. Male Wistar rats were randomly divided into the control group (n=80 and the precancerous liver cirrhosis group (n=40. The control group received saline injection and the liver cirrhosis group received 50 mg/kg DEN i.p. twice a week for 12 weeks. All animals underwent plain CT scanning, CTP, and contrast-enhanced CT scanning. Scanning parameters were optimized by adjusting the diatrizoate concentration, the flow rate, and the delivery time. The hemodynamics of both groups was further compared using optimized multislice spiral CTP imaging. Results. High-quality CTP images were obtained with following parameters: 150 kV; 150 mAs; 5 mm thickness, 5 mm interval; pitch, 1; matrix, 512×512; and FOV, 9.6 cm. Compared to the control group, the liver cirrhosis group had a significantly increased value of the hepatic arterial fraction and the hepatic artery perfusion (P<0.05 but significantly decreased hepatic portal perfusion and mean transit time (P<0.05. Conclusion. Multislice spiral CTP imaging can be used to evaluate the hemodynamic changes in the rat model of liver cirrhosis with precancerous lesions.

  10. Dose reduction in subsecond multislice spiral CT examination of children by online tube current modulation

    The potential of online tube current modulation in subsecond multislice spiral CT (MSCT) examinations of children to reduce the dose without a loss in image quality is investigated in a controlled patient study. The dose can be reduced for oval patient sectional view without an increase in noise if the tube current is reduced where the patient diameter and, consequently, attenuation are small. We investigated a product version of an online control for tube current in a SOMATOM Sensation 4 (Siemens, Forchheim). We evaluated image quality, noise and dose reduction for examinations with online tube current modulation in 30 MSCT of thorax/abdomen and abdomen and compared mA s for tube current modulation to the mA s in standard weight-adapted children protocols. Image quality was rated as ''very good,'' ''good,'' ''diagnostic'' and ''poor'' in a consensus by three radiologists. Noise was assessed in comparison to 24 MSCT examinations without tube current modulation measured as SD in ROIs. The dose was reduced from 26 to 43% (mean 36%), depending on the patient's geometry and weight. (orig.)

  11. Multiplanar functional imaging of the larynx and hypopharynx with multislice spiral CT

    Lell, Michael M.; Greess, Holger; Janka, Rolf; Bautz, Werner A.; Baum, Ulrich [University Erlangen-Nuremberg, Institute of Diagnostic Radiology, Erlangen (Germany); Hothorn, Torsten [University Erlangen-Nuremberg, Department of Medical Informatics, Biometry and Epidemiology, Erlangen (Germany)

    2004-12-01

    The purpose of this study is to evaluate multislice spiral CT (MSCT) in multiplanar functional imaging of the larynx and hypopharynx and to define the optimal image planes for the delineation of the tumor and specific anatomical structures. Forty patients with suspected tumors of the larynx or hypopharynx were examined with MSCT during quiet breathing (QB), E-phonation (EP) and modified Valsalva maneuver (VM). Images were read in the axial, coronal and sagittal planes. Overall image quality, delineation of the tumor and anatomic structures for different conditions and orientations were graded using a three-point scale; the conditional permutation test was applied to detect quality differences. Differences between image types were statistically significant. The axial plane was superior in overall image quality and the delineation of the tumor, pyriform sinus, vocal cords and fat within the parapharyngeal/visceral space. The coronal plane was best for delineating the ventricle and the paraglottic space, the sagittal plane for the retropharyngeal and the preepiglottic space. For tumor detection, sensitivity, specificity and accuracy were 0.92, 1.0 and 0.93 for QB.ax, 0.94, 0.8 and 0.92 for EP.ax and 0.85, 1.0 and 0.87 for VM.ax, respectively. Examination during QB should be the standard procedure; additional scanning with EP improved tumor assessment. (orig.)

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

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

  13. Enhanced spiral CT scan Nursing%螺旋CT增强扫描的护理体会

    杨柳

    2014-01-01

    目的:探讨行螺旋CT增强扫描患者的护理体会。方法选取我院CT室在2012年1月至2013年12月收治的行螺旋CT增强扫描的患者40例,对所有患者均加强扫描前、中、后的护理。结果本组40例患者均顺利完成CT增强扫描,轻度过敏反应3例,中度过敏反应1例,无重度过敏反应,且所有患者均获得较好质量的影像图像。结论加强对行螺旋CT增强扫描患者的护理,尤其是对造影剂应用方面的护理,可更好提高扫描效果,减少不良反应。%Objective To investigate enhanced spiral CT scan of the patient care experience .Methods CT room in our hospital from January 2012 to December 2013 admitted row spiral CT scans of 40 patients,all patients were strengthened before scanning,during and after care.Results 40 patients were successfully enhanced CT scan,mild allergic reactions three cases,one case of moderate allergic reactions,no severe allergic reactions,and all patients get better quality video images.Conclusion Strengthening row spiral CT scan of the patient care,especially inIs the application of contrast agent care,can better improve the scan results,reduce adverse reactions.

  14. Dynamic study of the larynx with spiral CT in the tumors of the pyriform sinus and supraglottis

    The purpose of this study is to evaluate the CT findings of tumor in the pyriform sinus, and to assess by functional study of the larynx the extent to which its characteristic findings differ from those of supraglottic tumor. CT scans of 14 patients with tumor in the pyriform sinus were reviewed and compared with those of 17 patients with supraglottic tumor. In all cases, spiral CT scanning involved both quiet breathing and modified breath holding : we evaluated the images and analysed the primary site of tumors and the displacement of air in the pyriform sinus. Extra and intralaryngeal extension of the tumors was also assessed. In tumors in the pyriform sinus, CT findings were thickening of more than two walls in 14, the siplacement of air in 9, extralaryngeal extension in 13, extension to the post-cricoid space patients. In supraglottic tumors, CT findings were thickening of the medial wall in 17, extralaryngeal extension in 1, extension to the post-cricoid space in 1, invasion of the ipsilateral paralaryngeal space in 17, and of the contralateral paralaryngeal space in 6, invasion of the pre-epiglottic space in 11, and widening of the cricothyroid space in 9 patients. In this type of tumor, the displacement of air was not seen. The characteristic CT findings of tumor in the pyriform sinus were thickening of more than two walls of the pyriform sinus and the anterior or medial displacement of air. To assess the site at which a tumor originates, spiral CT scanning is needed, together with functional study. (author). 12 refs., 1 tab., 4 figs

  15. Differentiation between sarcoidosis and Hodgkin’s lymphoma based on mediastinal lymph node involvement pattern: Evaluation using spiral CT scan

    The purpose of this study was to determine the specific and detailed anatomic sites and morphologic characteristics of mediastinal lymph nodes on spiral computed tomography for the purpose of differentiation between sarcoidosis and Hodgkin’s lymphoma. Anatomical distribution of mediastinal lymph nodes on spiral CT was reviewed in 39 patients with sarcoidosis and 37 patients with Hodgkin’s lymphoma using the International Association for the Study of Lung Cancer (IASLC) lymph node map. Other morphologic features such as lymph node calcification or coalescence of adjacent lymph nodes were also compared. Zone 10 was involved more often in sarcoidosis than in Hodgkin’s lymphoma. On the other hand, there was a higher tendency for presence of zone 1 and 3 as well as retrocrural and internal mammary lymphadenopathy in Hodgkin’s lymphoma than in sarcoidosis. Sarcoidosis presented with intranodal calcifications more often than Hodgkin’s lymphoma. Coalescence, pressure effect on adjacent structures and central cavitations were significantly more common in Hodgkin’s lymphoma. Findings of the present study indicate that specific anatomical distribution and morphological patterns of mediastinal lymph nodes, as demonstrated on spiral CT, can be useful in differentiating sarcoidosis from Hodgkin’s lymphoma

  16. Automatic detection of pulmonary nodules at spiral CT: clinical application of a computer-aided diagnosis system

    The aim of this study was to evaluate a computer-aided diagnosis (CAD) workstation with automatic detection of pulmonary nodules at low-dose spiral CT in a clinical setting for early detection of lung cancer. Eighty-eight consecutive spiral-CT examinations were reported by two radiologists in consensus. All examinations were reviewed using a CAD workstation with a self-developed algorithm for automatic detection of pulmonary nodules. The algorithm is designed to detect nodules with diameters of at least 5 mm. A total of 153 nodules were detected with at least one modality (radiologists in consensus, CAD, 85 nodules with diameter <5 mm, 68 with diameter ≥5 mm). The results of automatic nodule detection were compared to nodules detected with any modality as gold standard. Computer-aided diagnosis correctly identified 26 of 59 (38%) nodules with diameters ≥5 mm detected by visual assessment by the radiologists; of these, CAD detected 44% (24 of 54) nodules without pleural contact. In addition, 12 nodules ≥5 mm were detected which were not mentioned in the radiologist's report but represented real nodules. Sensitivity for detection of nodules ≥5 mm was 85% (58 of 68) for radiologists and 38% (26 of 68) for CAD. There were 5.8±3.6 false-positive results of CAD per CT study. Computer-aided diagnosis improves detection of pulmonary nodules at spiral CT and is a valuable second opinion in a clinical setting for lung cancer screening despite of its still limited sensitivity. (orig.)

  17. Spiral CT arthrography of multiplanar reconstruction and virtual arthroscopy technique in diagnosis of knee with internal derangements

    熊传芝; 郝敬明

    2004-01-01

    5Objective:To evaluate the values of spiral CT arthrography with multiplanar reconstruction and virtual arthroscopy technique in diagnosis of internal derangements of the knee. Methods:Ten bovine knees were used for experiment. The menisci, anterior and posterior cruciate ligaments and cartilage of these 10 bovine knees were injured with a hook. Each of the joints was injected with 100 mi air, then soon scanned with a PQ6000 spiral computed tomography scanner. The data obtained was input into the work station, and multiplanar reconstruction technique was used to illustrate lesions in the knees. The results of CT diagnosis were compared to those found by gross inspection of the specimens. Clinically, 10 knees of 9 patients diagnosed as internal derangement were evaluated with the same method after 50-70 ml air was injected into each of the joints. Nine months later, the data of 2 patients were used for CT endoscopy reconstruction. The results were compared with intraoperative findings. Results:Experimentally,the sensitivity and specificity were 88.9% and 93.9% by detection of meniscal abnormalities, 85.7% and 100% by detection of cruciate ligament lesions, and 72.7% and 100% by detection of cartilage damage, respectively. Clinically, the sensitivity and specificity were 90. 0% and 95.0% by detection of meulscal lesion. As to ligament, the figures were 85.7% and 100% respectively. Images of virtual arthroscopy simulated the images of real arthroscopy. Conclnsious:Spiral CT arthrography of multiplanar reconstruction technique offers fime images of internal structures of the knee, with clear border and internal structure. It is an accurate method for detecting meulscal, cruciate and collateral ligament and cartilaginous lesions that cause internal derangement of the knee.Virtual arthroscopy technique is a hopeful method for detecting reasons of derangement of the knee.

  18. Quantification of cardiac function with multislice spiral CT using retrospective EKG-gating: comparison with MRI

    Purpose: To quantify left ventricular function derived from retrospectively ECG-gated multislice spiral CT (MSCT) data sets in comparison to MRI. Materials and Methods: In 16 patients (14 males, 2 females, mean age 56.8 ± 11.5 years), retrospectively ECG-gated MSCT angiography of the coronary arteries and breath-hold steady state free precession cine MRI were performed. From MSCT data-sets, 20 axial image series were reconstructed every 5% of the RR interval. Multiplanar images were reformatted in the short axis orientation from axial images. End-systolic and end-diastolic images were selected. From these images end-systolic volume (ESV), end-diastolic volume (EDV) and stroke volume (SV) as well as the ejection fraction (EF) and myocardial mass (MM) were determined using the Simpson's method and compared with MRI. Furthermore, image quality was assessed for both imaging modalities using a four point grading scale. Results: All parameters were found to have an excellent correlation between MSCT and MRI data (Pearson's correlation coefficient 0.95 - 0.99), without clinically relevant differences between both modalities. On average, the difference between both methods was 0.5 ml for ESV, 0.8 ml for EDV, 1.3 ml for SV, 0.9% for EF and 2.3 g for MM. Image quality was slightly better for MRI (1.5 ± 0.65) than for MSCT (1.64 ± 0.74). Conclusion: Retrospectively ECG-gated MSCT angiography can not only visualize the coronary arteries but also enables precise quantification of the left ventricular function from the same MSCT data set. (orig.)

  19. Renal colic: a randomised trial of non-enhanced spiral CT compared to intravenous pyelography

    Full text: Many studies have demonstrated high accuracy of non-enhanced spiral CT (NECT) in renal colic, with sensitivities and specificities of 95-100%. There have been few studies comparing the diagnostic utility and outcomes of patients investigated with NECT and intravenous pyelography (IVP). Two hundred patients presenting to the Emergency Department of a tertiary public teaching hospital with suspected acute renal colic were randomised into undergoing NECT or IVP. Assessments were made of diagnostic utility, incidence of alternative diagnosis, requirement for further imaging, length of hospital stay, urological intervention rates, radiation dosage and costs. NECT was better than IVP in making a definitive diagnosis of ureteric calculus or of recent calculus passage (65/102, 66% versus 42/98, 41%). Calculi were missed in 2 patients in the IVP group.Two patients in each group had alternative diagnosis by initial imaging. There was no difference in the length of hospital stay or intervention rate. More plain x-rays during admission and more IVPs during follow-up were performed in the NECT group. Median effective radiation dosages were 2.97mSv (IVP) and up to 5mSv (NECT). NECT provides greater diagnostic utility in this randomised comparison, but no difference in measured outcomes. The incidence of alternative diagnoses was low, probably due to patient selection. Financial costs for each modality are comparable in a public tertiary hospital. Radiation dosages are higher for NECT and, for this reason it may be appropriate to consider limiting NECT use to patients who do not have classical symptoms of renal colic, to older patients and those with a contraindication to the administration of intravenous contrast media. Copyright (2002) Blackwell Science Pty Ltd

  20. Curved planar reformation of the facial nerve canal with multislice spiral CT

    Objective: To study the methods of delineating the whole length of bilateral facial nerve canals in one image. Methods: High resolution computed tomography of the temporal bone was performed in 60 cases (120 ears) by Philips Mx8000 multislice spiral CT. Parameters: 120 kV, 200-250 mAs, Collimation: 0.5 mm, Pitch: 0.875, Scan time: 0.75 s/ring, Matrix: 512 x 512, Reformation interval: 0.1-0.2 mm, Reformation matrix: 1024 x 1024. Curved planar reformation (CPR) images were prepared along the facial nerve canal in the axial plane, and in the coronal and sagittal plane of multiplanar reconstruction (MPR). In the axial plane, a reference line was traced following the facial nerve canal from the internal auditory meatus, through the labyrinthine segment, the tympanic segment up to the second genu and mastoid segment. Another two protocols of curved reformatting were adopted: (a) a curved line was delineated along the facial nerve canal on the coronal reformatted image; (b) a curved line was drawn along the facial nerve canal on the sagittal reformatted image. The reference lines were carefully revised and moved exactly to the center of each segment of the facial nerve canal. For displaying bilateral facial nerve canals in one image, one reference line should be drawn along bilateral facial nerve canals. Results: In 56 cases of 60 CPR, images in the axial plane, and coronal plane of MPR could show the unilateral or bilateral facial nerve canals clearly. The result of CPR of bilateral facial nerve canals in sagittal plane of MPR was unsatisfactory. The image on one side was often clear, but just part of it could be showed on the other. So the left and right facial nerve canals should be reformed separately. In 4 cases, CPR was unsatisfactory. In 1 of them the labyrinthine and tympanic segment had breaks because the patient's head shook during the scanning. In 3 of them the facial nerve canals were showed unsatisfactorily because of the inexact position of head during the

  1. 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

  2. Postoperative follow-up of Stanford type A aortic dissections with Spiral-CT and MRI: Normal imaging findings and typical complications; Spiral-CT und MRT der operierten Stanford Typ A-Aortendissektion: Verlauf und Komplikationen

    Sommer, T.; Pauleit, D.; Hofer, U.; Preusse, K.; Layer, G.; Schild, H. [Bonn Univ. (Germany). Radiologische Klinik; Abu-Ramadan, D.; Likungu, J. [Bonn Univ. (Germany). Klinik fuer Herz- und Gefaesschirurgie

    1998-02-01

    Purpose: To demonstrate normal postoperative Spiral-CT and MRI findings and typical complications in patients with aortic repair after Stanford type A aortic dissection. Results: The following postoperative complications were seen: Three pseudoaneurysms which developed at the proximal anastomoses of the Dacron prosthesis in two cases and at the insertion site of the reimplanted left coronary artery after implantation of a composite graft (Bentall procedure) in one case; one re-dissection; one perforation of the false lumen; periprostethic flow in one patient after surgical repair of type A dissection by the graft inclusion technique; progressive dilatation of the false lumen in 4 cases; dilatation of the aortic root in a Marfan patient after replacement of the ascending aorta. Conclusion: Precise knowledge of the surgical technique performed is crucial to accurate postoperative imaging evaluation. MRI is the method of choice in the postoperative follow-up of clinically stable patients with aortic dissections. (orig./AJ) [Deutsch] Ziel: Darstellung der verschiedenen Operationsverfahren bei der Stanford Typ A-Dissektion mit ihren typischen Aspekten in Spiral-CT und MRT sowie ihren spezifischen Komplikationen. Ergebnisse: Folgende postoperative Komplikationen traten auf: Drei Pseudoaneurysmen, die zweimal von der proximalen Anastomose des Aorta-ascendens-Ersatzes sowie einmal von der Insertionsstelle der reimplantierten linken Koronararterie (Operation nach Bentall) ausgingen; eine Re-Dissektion; eine gedeckte Perforation des falschen Lumens; periprothetischer Fluss nach Anwendung der Graft-Inclusion-Technik; progrediente Dilatation des falschen Lumens in 4 Faellen; aneurysmatische Erweiterung des originaeren Aortenbulbus bei einem Marfan-Patienten nach suprakoronarem Aorta-ascendens-Ersatz. Schlussfolgerung: Bei der postoperativen Verlaufskontrolle von Patienten mit Aortendissektionen mittels Spiral-CT und MRT sind Kenntnisse der verschiedenen Operationsverfahren mit

  3. Measuring of the airway dimensions with spiral CT images: an experimental study in Japanese white big-ear rabbits

    Objective: To measure the length, angle and their correlation of the main anatomical dimensions of the trachea and bronchus in experimental Japanese white big-ear rabbits with the help of spiral CT 3D images, in order to lay the foundation of treating the airway disorders with stenting in animal experiment. Methods: Multi-slice CT scanning of cervico-thoracic region was performed in 30 healthy adult Japanese white big-ear rabbits, the longitudinal, transversal dimensions of the trachea, the glottis-carina length, the inner diameter and length of bronchi, and the angle formed by bronchial long axis and sagittal section were measured. Results: No significant difference was found in the inner diameters of various parts of the trachea and upper apical bronchi. The angle formed by bronchial long axis and sagittal section were smaller than that of the left ones. And the inner diameters of the right main bronchus was bigger than the left ones. Conclusion: The complex branching structure of the rabbit airway tree can be well displayed on spiral CT 3D images. Through measuring and statistical analysis of the results the authors have got a regressive equation for estimating the value of the inner diameter, length, angle, etc. concerning the airway tree, which is very helpful for providing the useful anatomical parameters in rabbit experiment. (authors)

  4. Spiral CT of the lung in children with malignant extra-thoracic tumors: distribution of benign vs malignant pulmonary nodules

    The purpose of this paper is to clarify the distribution of benign vs malignant pulmonary nodules which are seen on spiral CT in children with malignant extra-thoracic solid tumors. Seventy-four children with known solid, extra-thoracic tumors underwent spiral CT of the chest. According to the initial and follow-up (interval 9.2±4.7 months) findings, the children were graded into four groups: I= normal; II= solitary nodule unchanged at follow-up; III= multiple nodules with one or more than one unchanged at follow-up; and IV= solitary or multiple nodules all changed at follow-up. Nodules without change at follow-up were regarded as benign. Forty-nine children did present with normal pulmonary CT exams. In 7 cases solitary pulmonary nodules were found unchanged (group II) at follow-up and in 2 cases (group III) some of the nodules were stationary. Thus, 12% (9 of 74) presented with at least one pulmonary nodule that did not change at follow-up. Solitary nodules (in groups II and IV) with a diameter <5 mm were in 70% (7 of 10) unchanged at follow-up and regarded as benign. In children with known solid extra-thoracic tumors at initial presentation, 70% of solitary nodules (<5 mm) may be benign. To avoid overstaging, smaller solitary nodules must not automatically be regarded as metastases. (orig.)

  5. Optimal scan time of dual-phase spiral CT in normal rabbit liver : effect of contrast injection rate

    To determine the effect of contrast injection rate on rabbit liver enhancement and the optimal temporal window for dual-phase spiral CT of rabbit liver at each injection rate Using spiral CT, seven New Zealand White rabbits underwent dynamic scanning at one level of liver. Three protocols of contrast injection rates were employed, namely 0.3ml/sec(group 1), 1 ml/sec(group 2) and 2 ml/sec(group 3). During 120 seconds of total scan time, the scan interval was 3 seconds. Densities of the aorta, liver and portal vein were averaged in equivalent time. The different injection rate protocols were compared for peak enhancement/time on a time density curve. Mean peak enhancement (HU) in equivalent time(secs) was 310/18(group 1), 383/9(group 2) and 357/6(group 3) in the aorta ; 34/36, 40/36 and 41/30 in the liver ; and 135/36, 153/24 and 170/21 in the portal vein. The temporal window during the arterial phase was 12-21 sec(group 1), 6-12 sec(group 2), and 6-12 sec(group 3). The temporal window during the portal phase was from 30 sec(0.3ml/sec), 21 sec(1ml/sec) and 21sec(2ml/sec). During dual-phase spiral CT, the temporal window for liver scanning should be determined according to each contrast injection rate. A slow contrast injection rate prolongs the temporal window during the arterial phase

  6. Spiral CT angiography and surgical correlations in the evaluation of intracranial aneurysms

    Preda, L.; Di Maggio, E.M.; La Fianza, A.; Dore, R.; Fulle, I.; Solcia, M.; Campani, R. [Istituto di Radiologia, IRCCS Policlinico S. Matteo, p.le C. Golgi, 2, I-27 100 Pavia (Italy); Gaetani, P.; Rodriguez y Baena, R. [Neurosurgery, Istituto Clinico ``Humanitas``, I-20089 Rozzano (Midway Islands) (Italy); Cecchini, A. [Servizio di Radiodiagnostica, IRCCS Policlinico S. Matteo, p.le C. Golgi, 2, I-27 100 Pavia (Italy); Infuso, L. [Neurochirurgia, Dipartimento di Chirurgia, IRCCS Policlinico S. Matteo, p.le C. Golgi, 2, I-27 100 Pavia (Italy)

    1998-06-02

    We investigated the accuracy of spiral computed tomography angiography (CTA) in the detection and study of intracranial aneurysms by comparing CTA with selective angiograms and surgical findings. Twenty-six patients (9 men and 17 women; mean age 53.1 {+-} 1.8 years) with suspected intracranial aneurysms were submitted to CTA (1- to 2-mm slices, pitch 1:1, 24 s, RI = 1) after a conventional CT examination showing subarachnoid hemorrhage (SAH) in 19 cases and during neuroradiological investigations performed for other reasons in 7 cases. One hundred twenty to 150 ml iodate contrast agent (0.3-0.4 gI/ml) were injected intravenously at 5 ml/s rate and with 12- to 25-s delay calculated with a preliminary test bolus. Three-dimensional shaded surface display (3D SSD) and maximum intensity projection (MIP) reconstructions were obtained from axial images. Then, within 48 h, all patients were submitted to digital subtraction angiography (DSA), with separate assessment of CTA and DSA findings. Twenty-two aneurysms shown by CTA were confirmed at DSA and surgery (true positives), whereas the vascular lesion was not confirmed at DSA in 2 cases (false positives). The presence of intracranial aneurysms was excluded at both CTA and subsequent DSA in 7 cases (true negatives) and there were no false negatives; sensitivity was 100 %, specificity 77.8 %, and diagnostic accuracy 93.5 %. Computed tomography angiography aneurysm location was confirmed at surgery in all cases, with very high accuracy in assessing the presence of an aneurysm neck (100 %). Computed tomography angiography accurately depicted the aneurysm shape in 20 of 22 cases, but failed to depict its multilobed nature in 2 cases. The mean aneurysm diameter calculated at CTA was 0.99 {+-} 0.12 cm vs 1.09 {+-} 0.11 cm at surgery (p < 0.01). The present results suggest that the high sensitivity of CTA, if confirmed by further studies, might help in avoiding having to resort to arteriography after negative CTA in SAH patients

  7. Assessment of bone segmentation quality of cone-beam CT versus multislice spiral CT: a pilot study.

    Loubele, M.; Maes, F.; Schutyser, F.A.C.; Marchal, G.; Jacobs, R.; Suetens, P.

    2006-01-01

    OBJECTIVES: The objective of this study was to quantitatively assess the quality of jawbone models generated from cone beam computed tomography (CBCT) by comparison with similar models obtained from multislice spiral computed tomography (MSCT). MATERIAL AND METHODS: Three case studies were performed

  8. 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.

  9. Difference of contrast enhancement characteristics of hepatic hemangiomas according to lesion size on two-phase spiral CT

    The purpose of this study is to determine the different of enhancement patterns of hepatic hemangioma according to the lesion size, using dual-phase spiral CT. Fifty-nine lesions in 45 patients with hepatic hemangiomas were subjected to spiral CT. According to size, the lesions were divided into two groups ( ≥ 2.5 cm : n=25). The enhancement patterns of the lesions were classified as one of four types (homogeneous hyperdense, peripheral hyperdense, central hyperdense, peripheral hyperdense, central hyperdense, or hypodense) during the early phase, and as one of five types (homogeneous hyperdense, peripheral hyperdense, central hyperdense, hypodense of isodense) during the delayed phase. We evaluated differences in enhancement patterns during the early and delayed phase according to lesion size. During the early phase, the enhancement patterns of lesions large than 2.5 cm were peripheral hyperdense (96%) or homogeneous hyperdense (4%); those of less than 2.5 cm were peripheral hyperdense (53%), homogenous hyperdense (26%), hypodense (18%), or central hyperdense (3%). Thus, hemangiomas in these two groups usually showed a peripheral enhancement patterns were more common. During the delayed phase, the enhancement patterns of lesions larger than 2.5 cm were peripheral hyperdense (3%), or isodense (3%). Thus, the enhancement patterns of lesions larger than 2.5 cm showed a homogeneous enhancement pattern. The enhancement patterns of hepatic hemangiomas differ according to lesion size. A knowledge of these differences is helpful in the diagnosis of hepatic hemangioma. (author). 16 refs., 2 tabs., 3 figs

  10. Prospectively ECG-triggered high-pitch spiral acquisition for coronary CT angiography using dual source CT: technique and initial experience

    Lell, Michael; Anders, Katharina [University of Erlangen, Diagnostic Radiology, Erlangen (Germany); Marwan, Mohamed; Schepis, Tiziano; Pflederer, Tobias; Kuettner, Axel; Ropers, Dieter; Daniel, Werner G.; Achenbach, Stephan [University of Erlangen, Department of Cardiology, Erlangen (Germany); Flohr, Thomas [CT Division, Siemens Healthcare, Forchheim (Germany); Eberhard-Karls-University, Institute of Diagnostic Radiology, Tuebingen (Germany); Allmendinger, Thomas; Thierfelder, Carsten [CT Division, Siemens Healthcare, Forchheim (Germany); Kalender, Willi; Ertel, Dirk [University of Erlangen, Institute of Medical Physics, Erlangen (Germany)

    2009-11-15

    We evaluated radiation exposure and image quality of a new coronary CT angiography protocol, high-pitch spiral acquisition, using dual source CT (DSCT). Coronary CTA was performed in 25 consecutive patients with a stable heart rate of 60 bpm or less after premedication, using 2 x 128 0.6-mm sections, 38.4-mm collimation width and 0.28-s rotation time. Tube settings were 100 kV/320 mAs and 120 kV/400 mAs for patients below and above 100-kg weight, respectively. Data acquisition was prospectively ECG-triggered at 60% of the R-R interval using a pitch of 3.2 (3.4 for the last 10 patients). Images were reconstructed with 75-ms temporal resolution, 0.6-mm slice thickness and 0.3-mm increment. Image quality was evaluated using a four-point scale (1 = excellent, 4 = unevaluable). Mean range of data acquisition was 113 {+-} 22 mm, mean duration was 268 {+-} 23 ms. Of 363 coronary artery segments, 327 had an image quality score of 1, and only 2 segments were rated as ''unevaluable''. Mean dose-length product (DLP) was 71 {+-} 23 mGy cm, mean effective dose was 1.0 {+-} 0.3 mSv (range 0.78-2.1 mSv). For 21 patients with a body weight below 100 kg, mean DLP was 63 {+-} 5 mGy cm (0.88 {+-} 0.07 mSv; range 0.78-0.97 mSv). Prospectively ECG-triggered high-pitch spiral CT acquisition provides high and stable image quality at very low radiation dose. (orig.)

  11. Low-dose protocol of the spiral CT in orthodontics: comparative evaluation of entrance skin dose with traditional X-ray techniques

    Cordasco, Giancarlo; Portelli, Marco; Militi, Angela; Nucera, Riccardo; Giudice, Antonino Lo; Gatto, Elda; Lucchese, Alessandra

    2013-01-01

    Background The aim of this study was to evaluate the amount of radiation doses absorbed by soft tissues (entrance skin dose) with a low-dose spiral computed tomography (CT) protocol compared to conventional X-ray techniques commonly used in orthodontics. Methods The amount of skin dose has been evaluated using a tissue-equivalent head-neck radiotherapy humanoid phantom with thermoluminescent dosimeters placed at the level of eye lens, parotid glands, and thyroid glands. CT images have been ta...

  12. 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.)

  13. Screenings of lung cancer with low dose spiral CT: results of a three year pilot study and design of the randomised controlled trial Italung-CT

    Purpose: To report the results of a three-year observational pilot study of lung cancer screening with low dose computed tomography (CT) and to present the study design of a randomised clinical trial named as Italung CT. Materials and methods: Sixty (47 males and 13 females, mean age 64±4.5 years) heavy smokers (at least 20 packs-year) underwent three low-dose spiral CT screening tests one year apart on a single slice or multislice CT scanner. Indeterminate nodules were managed according to the recommendations of the Early Lung Cancer Action Project. Results: Indeterminate nodules were observed in 33 (55%) of the subjects (60% at the baseline screening test, 24% at the first annual test and 16% at the second annual test). The size of the largest indeterminate nodule was <5mm in diameter in 20 subjects. 10 of whom showed the nodule at the baseline test. Forty-five subjects (75%) completed the first annual test and 42 (70%) the second annual test. One (1.6%) prevalent lung cancer (adenosquamous carcinoma) and one (2.2%) incident lung cancer (small cell cancer at the first annual examination) were observed, as well as pulmonary localisation of Hodgkin's lymphoma (at the second annual test). In addition, one subject underwent lung surgery for a chondromatous hamartoma. Conclusions: The results of the pilot study are substantially in line with those of other observational studies of greater sample size. This justifies optimism about the reliability of the results in the screened arm of the Italung Ct trial which hast just began

  14. The role of lung ventilation/perfusion scintigraphy (V/Q) in the diagnosis of pulmonary embolism in comparison with multislice spiral CT

    Objective: To evaluate the clinical value of lung ventilation/perfusion scintigraphy (V/Q) in the diagnosi of pulmonary embolism (PE) and compare with multislice spiral CT. Methods: Fifty-three consecutive patients with suspected PE underwent V/Q in one day procedure, multislice CT were also performed in same day. Results: Out of 53 patients with suspected PE 29 were diagnosed as PE. The sensitivity, specificity and accuracy of lung scintigraphy were 100%(29/29), 100%(24/24), 100%(53/53) respectively, and those of spiral CT were 72.4% (21/29), 92.3%(24/26) and 85% (45/53) respectively. The correlation rate of two modalities was 86.3 (Kappa=0.38). In patients with PE, 85 segments were determined as 'completely occluded' in CT scan, whereas 65 segments showed radioactive defects in lung scintigraphy. In 256 segments, CT showed partial occlusion, only 206 segments showed decrease in radioracer uptake and 26 segments were subsegmental defects. Conclusion: V/Q in one day procedure is feasible and sensitive for the diagnosis of pulmonary embolism. V/Q and spiral CT are complemental. (authors)

  15. Comparison between standard radiography and spiral CT with 3D reconstruction in the evaluation, classification and management of tibial plateau fractures

    Wicky, S.; Schnyder, P.; Meuli, R.A. [Department of Diagnostic and Interventional Radiology, University Hospital, Lausanne (Switzerland); Blaser, P.F.; Blanc, C.H.; Leyvraz, P.F. [Department of Orthopedics and Traumatology, University Hospital, Lausanne (Switzerland)

    2000-08-01

    The aim of this study was to compare the diagnostic efficiency of plain film and spiral CT examinations with 3D reconstructions of 42 tibial plateau fractures and to assess the accuracy of these two techniques in the pre-operative surgical plan in 22 cases. Forty-two tibial plateau fractures were examined with plain film (anteroposterior, lateral, two obliques) and spiral CT with surface-shaded-display 3D reconstructions. The Swiss AO-ASIF classification system of bone fracture from Mueller was used. In 22 cases the surgical plans and the sequence of reconstruction of the fragments were prospectively determined with both techniques, successively, and then correlated with the surgical reports and post-operative plain film. The fractures were underestimated with plain film in 18 of 42 cases (43%). Due to the spiral CT 3D reconstructions, and precise pre-operative information, the surgical plans based on plain film were modified and adjusted in 13 cases among 22 (59%). Spiral CT 3D reconstructions give a better and more accurate demonstration of the tibial plateau fracture and allows a more precise pre-operative surgical plan. (orig.)

  16. Comparison between standard radiography and spiral CT with 3D reconstruction in the evaluation, classification and management of tibial plateau fractures

    The aim of this study was to compare the diagnostic efficiency of plain film and spiral CT examinations with 3D reconstructions of 42 tibial plateau fractures and to assess the accuracy of these two techniques in the pre-operative surgical plan in 22 cases. Forty-two tibial plateau fractures were examined with plain film (anteroposterior, lateral, two obliques) and spiral CT with surface-shaded-display 3D reconstructions. The Swiss AO-ASIF classification system of bone fracture from Mueller was used. In 22 cases the surgical plans and the sequence of reconstruction of the fragments were prospectively determined with both techniques, successively, and then correlated with the surgical reports and post-operative plain film. The fractures were underestimated with plain film in 18 of 42 cases (43%). Due to the spiral CT 3D reconstructions, and precise pre-operative information, the surgical plans based on plain film were modified and adjusted in 13 cases among 22 (59%). Spiral CT 3D reconstructions give a better and more accurate demonstration of the tibial plateau fracture and allows a more precise pre-operative surgical plan. (orig.)

  17. Assessment of pulmonary function using pixel indexes of multiple-slice spiral CT low-dose two-phase scanning in chronic obstructive pulmonary disease

    张利华

    2012-01-01

    Objective To explore the values of pixel indexes (PI) with multiple-slice spiral CT low-dose two-phase scanning for assessing the pulmonary function in chronic obstructive pulmonary disease(COPD) . Methods Thirty-six patients with COPD (COPD group) and 30 healthy people(control group) underwent pulmonary

  18. CT findings in patients with chronic thromboembolic pulmonary hypertension; Spiral-CT bei chronisch thromboembolischer pulmonaler Hypertonie

    Heinrich, M.; Grgic, A.; Heckmann, M.; Kramann, B. [Abt. fuer Radiodiagnostik, Universitaetsklinikum des Saarlandes, Homburg (Germany); Tscholl, D.; Schaefers, H.J. [Abt. fuer Herz-, Thorax- und Gefaesschirurgie, Universitaetsklinikum des Saarlandes, Homburg (Germany); Uder, M. [Inst. fuer Diagnostische Radiologie, Friedrich Alexander-Univ. Erlangen-Nuernberg, Erlangen (Germany)

    2005-07-01

    Chronic thromboembolic pulmonary hypertension (CTEPH) is thought to be a rare complication of pulmonary embolism. However, it was recently demonstrated that CTEPH is more common than previously thought after pulmonary embolism. Without treatment, CTEPH is associated with a very high mortality rate. Making the correct diagnosis early is essential, because there is a potential curative treatment in the form of pulmonary thromboendarterectomy (PTE). Because of the unspecific clinical symptoms of CTEPH, the different imaging modalities play a crucial role in diagnosis making. Since the introduction of the multi-detector CT technology, CT has become an important part in the diagnostic work up of pulmonary embolism and CTEPH and is often used as a first-line diagnostic tool. CT is not only a reliable tool for the diagnosis of CTEPH, but also is helpful in estimating the operability of these patients. PTE is still associated with a mortality rate of about 10%. Particularly an insufficient decrease of the pulmonary vascular resistance after PTE leads to a very high mortality rate. Therefore, it is crucial to correlate the degree of the surgical accessible obstruction of the pulmonary vasculature with the degree of pulmonary hypertension in deciding for or against PTE. The aim of this review is to describe the CT findings in patients with CTEPH and their use in differentiating CTEPH from other diseases like acute pulmonary embolism and primary pulmonary hypertension. Moreover, the correlation of different CT imaging features with surgical success after PTE will be discussed. (orig.)

  19. 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.)

  20. Multislice spiral CT in pancreas examination: study on the effects of contrast enhancement with two injection conditions of contrast material

    Objective: To assess the effects of the intravenous injection rate and dose of contrast material on pancreatic parenchyma and peripancreatic vessel enhancement using multislice spiral CT. Methods: Forty patients without pancreatic disease were divided randomly into group A (n=20) and B (n=20). The injection rate was 5 ml/s for group A and 3 ml/s for group B, and the injection dose was 120 ml for group A and 90 ml for group B. All patients underwent non-enhanced and triple-phase (including arterial phase, pancreatic phase, and liver phase) enhanced scanning. The enhancement of pancreatic parenchyma at pancreatic phase was compared between the two groups, and the comparison of display rate and degree of peripancreatic blood vessels was done as well. The display degree of vessels was evaluated using a 0-3 point scale. Results: The pancreatic enhancement of group A was superior to that of group B (t=3.59, P2=26.27, P=0.00). The average value for the display degree of peripancreatic big vessels and the other major peripancreatic vessels was 2.93-3.00 and 0.60-2.80 in group A, and 2.33-2.80 and 0.07-1.53 in group B, respectively. There was also a significant difference (U=0.00 and 12.50, P=0.00 and 0.04) between group A and B for the display degree of peripancreatic big vessels, as well as the other major peripancreatic vessels. Conclusion: It is considered that 5 ml/s and 120 ml for injection rate and dose of contrast material in pancreas examination on multislice spiral CT is an optimized protocol, which helps the small lesion detection and improves the judgement accuracy of peripancreatic vascular invasion. (author)

  1. Evaluation of image quality and dose in thoracic spiral CT examination in patients with pulmonary carcinoma. Preliminary results

    We have applied criteria for CT quality defined in the European Guidelines to a samples of thoracic CT examinations for the indication of pulmonary carcinoma of 5 institutions of the Community of Madrid that have spiral CT equipment. The selected examinations have been evaluated independently by five radiologists to determine the degree of adherence to the quality criteria for image defined in the Guidelines s for examinations of general thorax. Dosimetric measurements carried out in parallel have served to estimate the values of CT (CTDIw) dose indices, dose-length product (DLP) and effective dose for every patient. The result show a high global adherence to the quality criteria (96%), with averages per institution being between 94% (in two institutions) and 98% (in three institutions). There are 10 of 16 criteria that are adhered to in all examinations of the sample: those which are not adhered to systematically are: two of visualization (1.1 and 1.4), with 92-96% fulfillment, and four of critical reproduction (2.6; 2.8; 2.9 and 2.10), with percentages of adherence between 91% and 96%. The average CTDIw values per institution are in the interval 12.9-19.1 mGy; those of DLP between 263 and 577 mGy cm and those of effective dose between 4.2 and 9.2 mSv. The DLP-image quality correlation in institutions with the best image quality was null in two of them and direct and moderate in the third. In both institutions with the poorest image: (Author) 20 refs

  2. 3-D segmentation algorithm of small lung nodules in spiral CT images

    Diciotti S; Picozzi G; Falchini M; Mascalchi M; Villari N; Valli G

    2008-01-01

    Abstract—Computed tomography (CT) is the most sensitive imaging technique for detecting lung nodules, and is now being evaluated as a screening tool for lung cancer in several large samples studies all over the world. In this report, we describe a semiautomaticmethod for 3-D segmentation of lung nodules in CT images for subsequent volume assessment. The distinguishing features of our algorithm are the following. 1) The user interaction process. It allows the introduction ...

  3. Evaluation of spiral CT three-dimensional computed tomography reconstruction guidance in percutaneous kyphoplasty

    Objective: To explore the clinical guiding value of spiral computed tomography(SCT) with three-dimensional computed tomography reconstruction (3-DCT)in percutaneous kyphoplasty (PKP). Methods: 24 patients prepared to be treated with PKP were examined under 3-DCT before the treatment. Results: According to the contra-indications shown by 3-DCT, 11 patients' operation were cancelled; the others were treated with PKP and got good outcomes due to the accurate data provided by 3-DCT. Conclusion: SCT plays an important role in PKP. (authors)

  4. CT angiography of the coronary arteries with a 16-row spiral tomograph. Effect of spatial resolution on image quality

    Purpose. To evaluate image quality of coronary CT angiography with retrospectively ECG-gated 16 multi-slice spiral CT (MSCT), reconstructed with 0.75 mm slice thickness for optimal spatial resolution and with 1.3 mm slice thickness, to produce spatial resolution comparable to a 4-MSCT.Materials and methods. Ten patients underwent coronary CT angiography with a 16-MSCT (Siemens Sensation 16, Forchheim, Germany) with 0.75 mm detector collimation. Raw helical CT data were retrospectively reconstructed using two different settings. Setting A: B20f smooth kernel, axial MPR with 1.3 mm slice thickness and 0.7 mm increment. Setting B: B35f ''HeartView'' medium-smooth kernel, 0.75 mm slice thickness, 0.5 mm increment. In the axial slices two regions of interest (ROIs) were placed in the area of the aortic root (AR) and more caudal in the area of the left ventricle (LV). Image noise was determined by the standard deviation of the CT numbers.Two readers determined visibility of coronary arteries by standardized maximum intensity projections (MIP) post-processing in left, right anterior and left anterior oblique projection plane from setting A and B. Each projection was rated on a five point rating scale concerning plaque delineation. Points determined for each data set were summed up and used for comparison.Results. No significant difference between the CT-numbers was found for setting A and B (A: 283.0 in AR/295.9 in LV and B: 282,9 in AR/297.2 in LV; p >0.2). However, the image noise was significantly different for setting A and B (A: 4.46 in AR/1.67 in LV and B: 8.16 in AR/7.38 in LV; p <0.01). Better delineation of the coronary arteries and atherosclerotic lesions could be achieved from MIP projections in setting B compared to setting A.Conclusion. Higher image noise is present in coronary 16-MSCT with thin-slice reconstruction compared to simulated 4-MSCT. However the MIP-reconstructions benefit most from the higher spatial resolution. (orig.)

  5. Detection of pulmonary metastases with pathological correlation: effect of breathing on the accuracy of spiral CT. Editor's note

    Background. CT of the chest for suspected pulmonary metastases in adults is generally performed using a breath-hold technique. The results may not be applicable to young children in whom breath-holding may be impossible. Objective. Determine the effect of breathing on the accuracy of pulmonary metastasis detection by spiral CT (SCT). Materials and methods. Prior to euthanasia four anesthetized dogs with metastatic osteosarcoma underwent SCT with a collimation of 5 mm and a pitch of 2, during both induced breath-hold and normal quiet breathing. Images were reconstructed as contiguous 5-mm slices. Macroscopically evident metastases were noted at postmortem. Hard-copy SCT images were reviewed by ten radiologists, each of whom circled all suspected metastases. SCT images were compared with postmortem results to determine true and false positives. Results. The pathologist identified 132 macroscopically evident pulmonary metastases. For metastasis detection, there was no significant difference between breath-hold SCT and breathing SCT. Conclusion. In our animal model, SCT can be performed during normal resting breathing without significant loss of accuracy in the detection of pulmonary metastases. (orig.). With 3 tabs

  6. Detection of pulmonary metastases with pathological correlation: effect of breathing on the accuracy of spiral CT. Editor`s note

    Coakley, F.V. [Abdominal Imaging Section, Department of Radiology, University of California, San Francisco, CA (United States); Cohen, M.D. [Department of Radiology, Riley Hospital for Children, Indianapolis, IN (United States); Waters, D.J. [Department of Veterinary Clinical Sciences, Purdue University, West Lafayette, IN (United States); Davis, M.M. [Department of Pathology, Riley Hospital for Children, Indianapolis, IN (United States); Karmazyn, B. [Department of Radiology, Riley Hospital for Children, Indianapolis, IN (United States); Gonin, R. [Division of Biostatistics, Department of Medicine, Riley Hospital for Children, Indianapolis, IN (United States); Hanna, M.P. [Division of Biostatistics, Department of Medicine, Riley Hospital for Children, Indianapolis, IN (United States)

    1997-07-01

    Background. CT of the chest for suspected pulmonary metastases in adults is generally performed using a breath-hold technique. The results may not be applicable to young children in whom breath-holding may be impossible. Objective. Determine the effect of breathing on the accuracy of pulmonary metastasis detection by spiral CT (SCT). Materials and methods. Prior to euthanasia four anesthetized dogs with metastatic osteosarcoma underwent SCT with a collimation of 5 mm and a pitch of 2, during both induced breath-hold and normal quiet breathing. Images were reconstructed as contiguous 5-mm slices. Macroscopically evident metastases were noted at postmortem. Hard-copy SCT images were reviewed by ten radiologists, each of whom circled all suspected metastases. SCT images were compared with postmortem results to determine true and false positives. Results. The pathologist identified 132 macroscopically evident pulmonary metastases. For metastasis detection, there was no significant difference between breath-hold SCT and breathing SCT. Conclusion. In our animal model, SCT can be performed during normal resting breathing without significant loss of accuracy in the detection of pulmonary metastases. (orig.). With 3 tabs.

  7. 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.

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

    The aim of this study is to investigate the relationship between16-slice spiral CT perfusion imaging and tumor angiogenesis and VEGF (vascular endothelial growth factor) expression in patients with benign and malignant pulmonary nodules, and differential diagnosis between benign and malignant pulmonary nodules. Sixty-four patients with benign and malignant pulmonary nodules underwent 16-slice spiral CT perfusion imaging. The CT perfusion imaging was analyzed for TDC (time density curve), perfusion parametric maps, and the respective perfusion parameters. Immunohistochemical findings of MVD (microvessel density) measurement and VEGF expression was evaluated. The shape of the TDC of peripheral lung cancer was similar to those of inflammatory nodule. PH (peak height), PHpm/PHa (peak height ratio of pulmonary nodule to aorta), BF (blood flow), BV (blood volume) value of peripheral lung cancer and inflammatory nodule were not statistically significant (all P > 0.05). Both showed significantly higher PH, PHpm/PHa, BF, BV value than those of benign nodule (all P < 0.05). Peripheral lung cancer showed significantly higher PS (permeability surface) value than that of inflammatory nodule and benign nodule (all P < 0.05). BV, BF, PS, MTT, PH, PHpm/PHa, and MVD among three groups of peripheral lung cancers were not significantly (all P > 0.05). In the case of adenocarcinoma, BV, BF, PS, PHpm/PHa, and MVD between poorly and well differentiation and between poorly and moderately differentiation were statistically significant (all P < 0.05). The peripheral lung cancers with VEGF positive expression showed significantly higher PH, PHpm/PHa, BF, BV, PS, and MVD value than those of the peripheral lung cancer with VEGF negative expression, and than those of benign nodule with VEGF positive expression (all P < 0.05). When investigating VEGF negative expression, it is found that PH, PHpm/PHa, and MVD of inflammatory nodule were significantly higher than those of peripheral lung cancer

  9. 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

    der Mehrzeilen-Spiral-CT einer simultanen Diagnostik der Lungenembolie sowie der Venenthrombose von Beinen, Becken und Abdomen. Methode: Insgesamt 70 Patienten wurden bei klinischem Verdacht auf Lungenarterienembolie in der Mehrzeilen-Spiral-CT (LightSpeed QX/I, GE, USA) untersucht. Die Kontrastierung erfolgte mit einem einmaligen intravenoesen Bolus von 150 ml eines 30%igen jodhaltigen Kontrastmittels mit einem Flow von 4 ml/s. Die Untersuchung der Pulmonalarterien wurde mit einer Einzelschichtdicke von 2,5 mm und einem Pitch von 1,5 durchgefuehrt. Anschliessend wurden die Venen der unteren Koerperhaelfte - von den proximalen Unterschenkelvenen bis zum Eintritt der V. cava inferior in den rechten Vorhof - mit einer Schichtdicke von 3,75 mm und einem Pitch von 1,5 erfasst. Das Ergebnis der Untersuchung wurde in 48 Faellen mit der Lungenszintigraphie, in 46 Faellen mit der Dopplersonographie der Venen und in 10 Faellen mit der Phlebographie verglichen. Ferner wurde die Bildqualitaet nach subjektiven Kriterien auf einer Skala von 0 bis 4 beurtellt. Ergebnis: Bei allen Patienten gelang die gleichzeitige Darstellung der Pulmonalarterien bis in den subsegmentalen Bereich sowie der Becken- und Beinvenen einschliesslich der V. cava inferior. Die Bildqualitaet erreichte den hoechsten Score bei der Bewertung dieser arteriellen bzw. venoesen Gefaessabschnitte mit Ausnahme der Unterschenkelvenen (Score 2,4). Der Vergleich mit anderen bildgebenden Verfahren dokumentierte die Ueberlegenheit der Methode in der Diagnostik von haemodynamisch wirksamen Lungenembolien und von therapeutisch relevanten Venenthrombosen mit einer signifikant genaueren Einschaetzung zentraler Lungenembolien gegenueber der Szintigraphie und der Moeglichkeit der vollstaendigeren Detektion von Cavathrombosen im Vergleich zur Phlebographie und zur Dopplersonographie. Periphere Lungenembolien koennen allerdings dem Nachweis der Methode entgehen. Hier ist die Szintigraphie vorrangig. (orig.)

  10. 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)

  11. Clinical application of multislice spiral CT angiography in evaluation of anomalous vertebral artery

    Objective: To evaluate the diagnostic value of 16-slice spiral computed tomography angiography (MSCTA) in evaluation of anomalous vertebral artery. Methods: MSCTA data from 32 patients with anomalous vertebral artery were retrospectively analyzed. Results: 22 cases had vertebral artery course variation (bended into the C5, C4 or C3 foramen transversarium), 7 cases had variation in the prevertebral segments of vertebral arteries, 15 patients had unilateral vertebral congenital stenosis, 1 case had double vertebral artery branch, 1 case had vertebral arterial fenestration, and 2 cases had vertebral artery in one side that did not converged upon basilar artery and unilateral vertebral artery formed basilar artery. Conclusion: MSCTA is a useful noninvasive imaging tool for the diagnosis of vertebral artery variations. (authors)

  12. The diagnostic value of high resolution spiral CT in fracture of the skull base%高分辨率螺旋 CT 对颅底骨折的诊断价值

    徐柱荣

    2014-01-01

    目的:探讨高分辨率螺旋CT扫描对颅底骨折的诊断价值。方法对57例临床疑有颅底骨折的患者先行常规CT扫描,然后行高分辨率螺旋CT扫描,并对结果进行对比分析。结果57例患者中高分辨率螺旋CT扫描检出颅底骨折45例,常规CT扫描检出10例,两者比较差异具有统计学意义( P<0.01)。结论螺旋CT高分辨率检查技术显著提高颅底骨折的检出率,对临床治疗有重要的指导意义,应作为常规检查方法。%Objective To explore the diagnosis value of high resolution spiral CT scan in fracture of the skull base .Methods Fifty-seven patients with clinically suspected skull base fracture received conventional CT scan -ning first, then received high resolution spiral CT scanning , and the result analysis were compared .Results In 57 patients, 45 cases of fracture of the skull base were detected by high resolution spiral CT scan , 10 cases were detec-ted by conventional CT scanning , showing significant difference between two methods ( P<0.01 ) .Conclusion Spi-ral CT high-resolution technique significantly increase the detection rate of the fracture of the skull base , and has im-portant guiding significance to the clinical treatment , should be used as a routine examination method .

  13. Diagnosis of normal variation of hepatic artery on axial image of spiral CT: importance of a vascular structure in a portocaval space and fissure of ligamentum venosum

    To determine the predictaility of an aberrant hepatic artery by detection of a vessel in the portocaval space or fissure for the ligamentum venosum, as seen on arterial-phase spiral CT images. Axial spiral CT scans (10mm section thickness, 10mm table feed) were obtained in 100 patients with hepatic mass and were examined by two radiologists. In each case, each determined whether a vessel was located in the portocaval space or fissure for the ligamentum venosum, and the type of aberrant artery. All patients underwent conventional angiography and the results were interpreted by another radiologist and compared with the results as shown on CT. Twelve-one cases with a vessel within the portocaval space and 14 with a vessel within the fissure for the ligamentum venosum showed variation of the hepatic artery. When a vessel was located transversely in the portocaval space, sensitivity, specificity, and positive and negative predictive value of an aberrant hepatic artery were 94%, 100%, 100% and 99%, respectively;when a vessel was located in the fissure for the ligamentum venosum, the corresponding rates were 88%, 100%, 100%, and 98%. The detection on arterial-phase spiral CT images of a vessel in the portocaval space or fissure for the ligamentum venosum can reliably predict the existence of an aberrant hepatic artery

  14. Use of spiral CT and the contrast medium iohexol to determine in one session aortorenal morphology and the relative glomerular filtration rate of each kidney

    The aim of this study was to determine the relative glomerular filtration rate (GFR), i.e. the GFR of each kidney in percent of total GFR, by spiral CT. In 41 patients, who were part of a follow-up program after endoluminal stent grafting of aortic aneurysm, spiral CT with the contrast medium iohexol was used to evaluate the morphology of the aorta and kidneys. The opportunity was taken to utilize the already injected iohexol to determine the relative GFR with an extra CT sequence. In each patient two determinations were made, 6 or 12 months apart. The amount of a GFR marker accumulating in Bowman's space, tubuli, and renal pelvis within 2-3 min after i.v. injection, before any marker had left the kidney via the ureter, was defined as proportional to the GFR of that kidney. The renal accumulation of iohexol was obtained by spiral CT using 10-mm collimation and a table speed of 10 mm/s (pitch ratio 1:1) from the upper to the lower poles. The correlation coefficient between the relative GFR of each kidney determined at the first and second examination was excellent (r=0.99) with a median (range) difference of 1% (0-6%) of total GFR. The radiation dose calculated as the mean absorbed dose to the kidneys was 50 mGy and the effective dose 5 mSv. The morphology of aorta and kidneys and the relative GFR of each kidney can be determined in one session with spiral CT using iohexol as both angiographic contrast medium and as a GFR marker. It is also possible to take some plasma samples in the same session to determine iohexol concentration to calculate the body clearance of iohexol (or take plasma and urine samples to calculate the renal clearance of iohexol). (orig.)

  15. Comparison of Image Registration Based Measures of Regional Lung Ventilation from Dynamic Spiral CT with Xe-CT

    Ding, Kai; Fuld, Matthew K; Du, Kaifang; Christensen, Gary E; Hoffman, Eric A; Reinhardt, Joseph M

    2012-01-01

    Purpose: Regional lung volume change as a function of lung inflation serves as an index of parenchymal and airway status as well as an index of regional ventilation and can be used to detect pathologic changes over time. In this article, we propose a new regional measure of lung mechanics --- the specific air volume change by corrected Jacobian. Methods: 4DCT and Xe-CT data sets from four adult sheep are used in this study. Nonlinear, 3D image registration is applied to register an image acquired near end inspiration to an image acquired near end expiration. Approximately 200 annotated anatomical points are used as landmarks to evaluate registration accuracy. Three different registration-based measures of regional lung mechanics are derived and compared: the specific air volume change calculated from the Jacobian (SAJ); the specific air volume change calculated by the corrected Jacobian (SACJ); and the specific air volume change by intensity change (SAI). Results: After registration, the mean registration err...

  16. Pulmonary embolism: Prospective comparison of spiral CT with ventilation - perfusion scintigraphy

    The pulmonary thromboembolism (PTE) it is an entity common with great morbidity and mortality that it requires a diagnosis soon and specify. Commonly the ventilation gammagraphy - perfusion has been the used exam of first more frequent line when one suspects the PTE but unfortunately a great quantity of reports is called of intermediate probability, for what requires complementary studies, to confirm or to discard the diagnosis. A prospective study was made with 142 patients that had suspicion of TEP in the hospital of Vancouver (Canada) and in the hospital of Calmette (France), being carried out in all gammagraphy of ventilation-perfusion and helical CT, being only taken to lung angiography to those that not had high clinical suspicion of TEP with gammagraphy or helical CT very suggestive or tuneless, undergoing the results valuation for different observers

  17. Hepatic tumors in children: Spiral CT findings and their significance for differential diagnosis

    Liver tumors in childhood are rare. They can be subdivided in benign or primary and secundary malignent liver tumors. The prognosis of malignant liver disease has improved due to extended therapy in the past few years. Thus, diagnosis of liver tumors in childhood gains in significance. After a suspect ultrasound diagnosis, usually computed tomography (CT) is used as a radiologic sectioning method. Guided by a retrospective analysis of 15 cases, the importance of the Helical-CT is presented. Helical-CT is a good diagnostic method for pediatric cases due to reduced scan times. By the basis of clinical data, distribution, and density, various differential diagnoses can be made. Benign liver tumors, especially cysts and frequently haemangioma, can easily be diagnosed and controlled because of their typical echogenicity and contrast visualisation. In cases of hamartoma, focal nodal hyperplasia, and adenoma computed tomography diagnosis is often necessary. Primary malignant liver tumors can prove to be unilocular hepatoblastomas or hepatocellular carcinomas, while disseminated liver invasions usually are considered as metastatic liver tumors of kidney or adrenal cancer. (orig.)

  18. Pulmonary emphysema quantitation with Computed Tomography. Comparison between the visual score with high resolution CT, expiratory density mask with spiral CT and lung function studies; Valutazione quantitativa dell`enfisema polmonare mediante Tomografia Computerizzata. Confronto tra il punteggio visivo con alta risoluzione nell`inspirazione, maschera della densita` automatica con Tomografia Computerizzata spirale nell`espirazione ed esami funzionali respiratori

    Zompatori, Maurizio; Battaglia, Milva; Rimondi, Maria Rita; Vivacqua, Donatella; Biscarini, Manuela [Policlinico S. Orsola-Malpighi, Bologna (Italy). Radiologia padiglione Pneumonefro; Fasano, Luca; Pacilli, Angela Maria Grazia; Guerrieri, Aldo; Fabbri, Mario [Policlinico S. Orsola-Malpighi, Bologna (Italy). Istituto di Fisiopatologia Respiratoria; Cavina, Mauro [Policlinico S. Orsola-Malpighi, Bologna (Italy). TSRM. Servizio di Tomografia Computerizzata

    1997-04-01

    CT is the most accurate method to detect pulmonary emphysema in vivo. They compared prospectively two different methods for emphysema quantitation in 5 normal volunteers and 20 consecutive patients with chronic obstructive pulmonary disease (COPD). All subjects were submitted to function tests and HRCT; three scans were acquired at preselected levels during inspiration. The type and extent of pulmonary emphysema were defined by two independent observers under blind conditions. Disagreements were subsequently settled by consent. All subjects were also examined with expiratory spiral CT using a density mask program, at two different cut-off levels (-850,-900 HU). Visual score and expiratory spiral density mask values (-850 HU) were significantly correlated (r = 0.86), but the visual extent of emphysema was always higher than shown by expiratory spiral CT. The emphysema extent assessed with both CT methods correlated with the function result of expiratory airflow obstruction and gas diffusion impairment (visual score versus forced expiratory volume in one second: r = -0.81, versus single breath carbon monoxide diffusion: r = -0.78. Spiral expiratory density mask -850 HU versus forced expiratory volume in one second: r = -0.85 versus single breath carbon monoxide diffusion: r = -0.77). When -900 HU was used as the cut-off value for the expiratory density mask, the correlation with single breath carbon monoxide diffusion worsened (r = -0.56). Visual score and expiratory density mask -850 HU gave similar results and permitted COPD patients to be clearly distinguished from normal controls (p < 0.01). They believe the true residual volume should lie somewhere in between the CT value and the function results with the helium dilution technique and conclude that the extent of pulmonary emphysema can be confidently assessed with CT methods. Finally, the simple visual score may be as reliable as such highly sophisticated new methods as the spiral expiratory density mask

  19. 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.

  20. Evaluation of transplant renal artery stenosis examined by multislice spiral CT angiograph

    Objective: To evaluate the value of multislice CT angiography (MSCTA) in transplant renal artery stenosis (TRAS). Methods: Fifteen cases of TRAS underwent enhanced MSCT scanning postoperation. Multi-planar reformation (MPR), CPR (curved-planar reformation), volume rendering (VR), multi-planar volume reformation (MPVR), maximum intensity projection (MIP) and vessel probe (VP) reformation were performed to observe transplant kidney's artery. To analyse all the reconstruction technique and find the advantage and shortage of them. Results: CT findings of TRAS showed local vascular thining and enhanced renal parenchyma degradinged. CT reconstruction technique: 1 Trans-plant kidney's artery of only one case could be shown in the same MPR plane; 2 Transplant kidney's artery of 13 cases could be shown in CPR coronal and sagittal plane; 3 with 15 cases of VR, stage of courser and shape of angiostegnosis could be observed clearly through rotating the reconstruction image from different directions; 4 15 cases of MPVR could reveal transplant kidney's artery and TRAS at the same time; 5 9 cases of MIP could show TRAS in one plane; 6 15 cases of VP could show condition inside the vessel of transplant kidney, with the degree of stenosis appeared clearly. Of 15 cases of TRAS, stenosis occurred in stoma (8 cases), distant place from stoma (4 cases), stoma and distant place form stoma (2 cases), stenosis occurred in whole range (oe case). Conclusion: MSCTA has an important role as an imaging technique to evaluate TRAS of transplant kidney, which can replace DSA. It can reveal the stenosis part of vessel and direct PTA, to evaluate therapeutic effect of endovascular stent placement. MSCTA will be widespread used clinically. (authors)

  1. Non-contrast spiral CT for patients with suspected renal colic

    Katz, D.S. [Department of Radiology, Stanford University Medical Center, 300 Pasteur Drive, CA 94305-5105 (United States); Lane, M.J. [Department of Radiology, Stanford University Medical Center, 300 Pasteur Drive, CA 94305-5105 (United States); Sommer, F.G. [Department of Radiology, Stanford University Medical Center, 300 Pasteur Drive, CA 94305-5105 (United States)

    1997-06-01

    Renal colic, defined as acute flank pain caused by the passage of a ureteral calculus, is a common condition, but the correct diagnosis may not be apparent clinically. For decades, intravenous urography has been the test of choice for evaluating patients with suspected renal colic. Recently, unenhanced (non-contrast) helical CT has been shown to be an accurate and highly effective examination which can be used instead of intravenous urography. In this article, the technique is reviewed in detail, including its advantages and potential pitfalls. (orig.). With 12 figs.

  2. Multislice spiral CT in pancreas examination: optimal multi-phase enhanced scan delay time

    Objective: To ascertain the optimal multi-phase scan enhanced delay time of MSCT in pancreas examination. Methods: Sixty-one patients without pancreatic disease were choosed at randomly in the two approaches study: Firstly, 21 patients underwent single-level enhanced serial CT scanning of the pancreas. By means of injection dosage of 120 ml contrast at 5 ml/s rate, CT value of the peripancreatic aorta and portal vein, pancreatic and hepatic parenchyma was measured respectively in order to determine the optimal delay time of multi-phase scanning (including arterial phase, pancreatic phase, and liver phase). Secondly, incremental pancreatic multi-phase MSCT were performed in 40 patients with the same dosage of contrast and injection rate. The display rate and degree (categorized on a scale of 0-3) of peripancreatic blood vessels at arterial phase and pancreatic phase was evaluated emphatically. Results: (1) The results of single-level enhanced serial CT scanning indicated that the average time was 30 s for peak enhancement of the peripancreatic aorta (the CT value of the peripancreatic aorta mostly exceeded 200 HU at 20 s), 40 s for the pancreatic parenchyma, 45 s for the peripancreatic portal vein, and 60 s for the hepatic parenchyma (the platform stage for the hepatic parenchyma ranged from 60 s to 80 s). (2) The results of step two showed that the display rate and the average score of display degree was 100% and 2.93-2.95 for the big peripancreatic arteries at the arterial phase,78%-98% and 0.85-2.63 for the other main peripancreatic arteries at the arterial phase; 100% and 2.80-2.88 for the big peripancreatic veins at the pancreatic phase, 90%-100% and 1.08-1.90 for the other main peripancreatic veins at the pancreatic phase. Conclusion: The optimal protocol of MSCT was the triple-phased enhancement scan for pancreas, and the recommended delay time was 20 s for arterial phase, 45 s for pancreatic phase, and 80 s for liver phase, respectively

  3. Non-contrast spiral CT for patients with suspected renal colic

    Renal colic, defined as acute flank pain caused by the passage of a ureteral calculus, is a common condition, but the correct diagnosis may not be apparent clinically. For decades, intravenous urography has been the test of choice for evaluating patients with suspected renal colic. Recently, unenhanced (non-contrast) helical CT has been shown to be an accurate and highly effective examination which can be used instead of intravenous urography. In this article, the technique is reviewed in detail, including its advantages and potential pitfalls. (orig.). With 12 figs

  4. 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)

  5. The selection of window width and levels for measuring the airway dimensions with spiral CT scan: an experimental study in Japanese white big-ear rabbits

    Objective: To investigate the optimal window width and window level for measuring the airway dimensions with spiral CT scan in Japanese white big-ear rabbits so as to lay the foundation for airway stenting in animal experiments. Methods: Multi-slice spiral CT scanning of cervico-thoracic region was performed in 30 healthy adult Japanese white big-ear rabbits, the anteroposterior and transversal diameter of the thoracic trachea, the anteroposterior diameter of the right and left bronchus were measured with lung window, mediastinum window and special fat window separately. The revealing rate of the tracheal wall and the measuring results in different windows and levels were recorded and compared with the anatomical data. The differences of the relevant data were statistically analyzed. Results: With lung window, the tracheal wall was well demonstrated, but the relevant data were smaller than that with mediastinum window. With mediastinum window, the data were bigger and the tracheal wall border appeared blurred. The results obtained with fat window were close to the actual anatomical data. Conclusion: For accurately measuring the anteroposterior and transversal diameter of the thoracic trachea in Japanese white big-ear rabbits with multi- slice spiral CT scan, fat window should be adopted, which is helpful for the preparation of tracheal and bronchial stents. (authors)

  6. 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)

  7. A comparison between ventilation/perfusion scintigraphy and multislice spiral CT in the diagnosis of chronic thromboembolic pulmonary hypertension

    Objective: Chronic thromboembolic pulmonary hypertension (CTEPH) is one of the important causes of pulmonary hypertension with poor prognosis. Several imaging techniques had been used to identify CTEPH. The aim of this study was to assess the reliability of ventilation/perfusion (V/Q) scintigraphy and multislice spiral CT pulmonary angiography (CTPA) in the diagnosis of chronic thromboembolic pulmonary hypertension, and the concordance rate (or 'agreement' as in the original article) between the two techniques. Methods: Forty-nine in-patients with pulmonary hypertension without history of con- genital heart disease, valvular heart disease and acute pulmonary embolism were included in this study. All these patients underwent V/Q scintigraphy as well as CTPA for detecting CTEPH. The final diagnosis was confirmed by pulmonary angiograpy. The results of V/Q scintigraphy and CTPA were compared with the χ2 test. Results: The sensitivity, specificity and accuracy of V/Q scintigraphy in diagnosis of CTEPH was 100.0% (17/17), 71.9% (23/32) and 81.6% (40/49), respectively, and those of CTPA was 94.1% (16/17), 81.2% (26/32) and 85.7% (42/49), respectively. The concordance rate was 75.5% (37/49, Kappa=0.513), no statistically significant difference (χ2=0.75, P > 0.05 ) was found between V/Q scintigraphy and CTPA. Conclusion: Both V/Q scintigraphy and CTPA are reliable to diagnose CTEPH. (authors)

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

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

    2013-12-15

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

  9. 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

  10. Left ventricular functional parameters using ECG-gated multidetector spiral CT in comparison with invasive ventriculography

    Purpose: To evaluate the accuracy of left ventricular function using a multidetector CT (MDCT) with retrospective ECG-gating and to compare the results with conventional ventriculography. Materials and methods: In 26 patients, retrospectively ECG-gated MDCT of the heart (Volume Zoom, Siemens, Germany) as well as conventional coronary angiography including ventriculography was performed to exclude or follow coronary artery disease. CT examination (120 KV, 400 mAs) was carried out with 4 x 1 mm collimation (500 ms gantry rotation time). For CT angiography, 150 ml of contrast media was injected intravenously at a flow rate of 4 ml/s. All data sets of the functional cardiac parameters were reconstructed in end-systolic and end-diastolic phase. End-systolic volume (ESV), end-diastolic volume (EDV) and ejection fraction (EF) were determined from multiplanar reformations orthogonally through the cardiac short axis and analyzed using special evaluation software (ARGUS, Siemens). The results were compared with ESV, EDV and EF obtained from invasive ventriculography. Results: In all cases, a sufficient quality of the MDCT images was achieved. EDV (150.1±16.2 ml MDCT vs. 138.7±16.9 ml ventriculography; mean difference 11.4±12.7 ml,. r=0.51) had an acceptable correlation to conventional ventriculography, and ESV (58.1±14.6 ml vs. 50.2±13.4 ml; mean difference 7.9±8.8 ml; r=0.81) and EF (60.9±13.6% vs. 64.9±12.7%; mean difference 4.0±6.2%; r=0.79) showed a good correlation. In comparison with invasive ventriculography, MDCT tended to overestimate significantly EDV (p=0.008) and ESV (p=0.003) and to underestimate EF (0.001). Conclusion: MDCT of the heart with retrospective ECG-gating enables efficient estimation of left ventricular function, providing important additional information of non-invasive cardiac imaging using MDCT. However, EDV and EVS were significantly overestimated and EF was underestimated in MDCT compared to ventriculography. (orig.)

  11. 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)

  12. Multislice spiral CT of left pulmonary artery sling with tracheobronchial anomaly

    Objective: To discuss the value of MSCT in diagnosis of left pulmonary artery sling (LPAS) with tracheobronchial anomaly. Methods: MSCT was performed in 9 children with LPAS and tracheobronchial anomalies, CT findings were analyzed retrospectively. Results: According to the Wells classification of LPAS, which includes two main types and two subtypes,there were 2 patients of type 1A, 3 patients of type 1 B, 2 patients of type 2A and 2 patients of type 2B. All of children had tracheobronchial stenosis.Local tracheobronchial stenosis was found in 4 patients (all were type 1) and long tracheobronchial stenosis in 5 patients (1 patient with type 1 and 4 patients with type 2). Conclusions: MSCT is an ideal imaging modality for simultaneously identifying LPAS and associated tracheobronchial anomalies. The Wells classification is very useful for operation planning. (authors)

  13. High-resolution MRI vs multislice spiral CT: Which technique depicts the trabecular bone structure best?

    The purpose of this study was to compare trabecular bone structure parameters obtained from high-resolution magnetic resonance (HRMR) and multislice computed tomography (MSCT) images with those determined in contact radiographs from corresponding specimen sections. High-resolution MR and MSCT images were obtained in 39 distal radius specimens. For HRMR the in-plane spatial resolution was 0.152 x 0.153 mm2 with a slice thickness of 0.9 and 0.3 mm using a 3D T1-weighted spin-echo sequence. For MSCT the resolution was 0.247 x 0.247 mm2 with a collimation of 1 mm. Using a diamond saw, 117 0.9- to 1-mm-thick sections were obtained from these specimens and contact radiographs were acquired. In the corresponding sections structure parameters analogous to bone histomorphometry were determined. Significant correlations between MR- and CT-derived structure parameters and those derived from the contact radiographs were found (p<0.01); r values of up to 0.75 were obtained for HRMR imaging and up to 0.70 for MSCT. On the average, structure parameters showed higher correlations for the MR- than for the CT-derived data. For the MR data the threshold algorithm used for binarizing the images substantially affected these correlations. In conclusion, trabecular bone structure parameters assessed in distal radius HRMR and MSCT images are significantly correlated with those determined in corresponding specimen sections (p<0.01). High-resolution MR-derived structure parameters, however, performed better in the prediction of trabecular bone structure. (orig.)

  14. Value of cardiac multislice spiral CT for the assessment of degenerative aortic stenosis: comparison with echocardiography

    Objective: To non-invasively assess the severity of aortic valve stenosis (AS) by the determination of aortic valve calcification (AVC) using multislice spiral computed tomography (MSCT). Materials and Methods: Forty-one consecutive patients (17 male, 24 female, mean age 71.0±7.9 years) with a history of AS and an aortic valve area ≤2 cm2 underwent retrospectively ECG-gated 4-slice MSCT and echocardiography. The AVCs were quantitatively assessed using the score described by Agatston as well as by calculating the calcium mass. The echocardiographically determined aortic valve area (AVA) and the severity of AS according to the ACC/AHA guidelines were compared to the degree of a aortic valve calcifications. Pearson's correlation coefficient, cut-off values, kappa test and F-test with post hoc Boneferroni t-tests were calculated. Results: Calcium scores were significantly higher in patients with severe AS, when compared to mild or moderate AS (p<0.001). In patients suffering from severe AS, the mean Agatston score was 4125.5±1168.9 (calcium mass 904.1±263.3) while in patients with moderate and mild AS the corresponding values were 1596.3±987.0 (319.1±208.3) and 785.9±390.1 (149.1±90.2), respectively. Pearson's correlation coefficients were r-=0.75 for the Agatston score and r=-0.72 for the calcium mass. There was a moderate agreement between severity of AS according to the ACC/AHA guidelines and the degree of AS determined from AVC scores with κ=0.6091 and κ=0.6985, respectively. Conclusion: Severe AS may be differentiated from moderate or mild AS using cardiac MSCT. Extensive calcifications of the aortic valve presenting with an Agatston-Score ≥2824 (calcium mass ≥611) indicate a severe AS and should be taken as an indication for further diagnostic workup. (orig.)

  15. Assessment value of combination of spiral CT, serum CRP and urine TPS-2 test in diagnosis and prognosis of acute pancreatitis

    To investigate the assessment efficiency of the severity and prognosis of acute pancreatitis by the combination of spiral CT, serum CRP and urine TPS-2 test, 79 cases of acute pancreatitis (AP), 50 cases of acute abdomen patients with non acute pancreatitis (NAP) and 50 cases of healthy persons with physical examination were retrospectively analyzed. The serum CRP and urine TPS-2 were detected,and serum CRP and urine TPS-2 of 19 cases in Group AP were dynamic monitored. The spiral CT scanning was performed at the same time,and then the data and CT findings were comprehensive analyzed. According to Balthazar CT grade: the patients were graded as Grade A (16 cases), Grade B (19 cases), Grade C (23 cases), Grade D (15 cases) and Grade E (6 cases). Grade A-C were for mild pancreatitis (MAP), and Grade D-E were for severe pancreatitis (SAP). The serum CRP level of Group SAP was significantly higher than that in Group MAP (P<0.05). The positive rate of urine TPS-2 in Group AP was higher than that in Group NAP (P<0.05). The positive rate of urine TPS-2 in Group SAP was higher than that of Group MAP, but the difference did not have statistical significance. The serum CPR concentration of Grade C-E was significantly higher than that of Grade A-B. The positive rate of urine TPS-2 of Grade B-E was significantly higher than that of Grade A, but the difference did not have statistical significance,and it had no statistical significance of positive rate of urine TPS-2 between Grade B-E. The combination of spiral CT, serum CRP and urine TPS-2 test has important clinical meaning in the evaluation, monitoring and prognosis of acute pancreatitis. (authors)

  16. Effect of imaging parameters of spiral CT scanning on image quality for the dental implants. Visual evaluation using a semi-anthropomorphic mandible phantom

    The purpose of this study was to evaluate the effect of parameters of spiral CT scanning on the image quality required for the planning of dental implants operations. A semi-anthropomorphic mandible phantom which has artificial mandibular canals and teeth roots was used as a standard object for imaging. Spiral CT scans for the phantom settled in water phantom with diameters of 20 and 16 cm were performed. Visibility of the artificial mandibular canal made of a Teflon tube and gaps between tooth apex and canal in the mandibular phantom was evaluated for various combinations of the slice thickness, tables speeds, angles to the canal, and x-ray tube currents. Teeth roots were made of PVC (poly vinyl chloride). The artificial mandibular canal was clearly observed on the images of 1 mm slice thickness. At the same table speed of 2 mm /rotation, the images of thin slice (1 mm) were superior to that of thick slice (2 mm). The gap between teeth apex and canal was erroneously diagnosed on the images with table speeds of 3 mm/rotation. Horizontal scanning in parallel to the canal result in poor image quality for observation of mandibular canals because of the partial volume effect. A relatively high x-ray tube current (125 mA) at thin slice (1 mm) scanning was required for scanning the mandibular phantom in 20 cm water vessel. Spiral scanning with slice thickness of 1 mm and table speeds of 1 of 2 mm/rotation seemed to be suitable for dental implants. The result of this study suggested that diagnosis from two independent spiral scans with a different angle to the object was more accurate and more efficient than single spiral scanning. (author)

  17. The Diagnostic Value of Spiral CT Scan on Peripheral Lung Cancer%螺旋CT扫描对周围型肺癌的诊断价值

    苏毅; 王乐乐; 倪傲

    2012-01-01

    目的 探讨螺旋CT扫描对周围型肺癌的诊断价值.方法 收集经螺旋CT扫描及病理证实的60例周围型肺癌,其中34例行增强CT扫描,对其CT影像学资料进行分析.结果 周围型肺癌的主要CT征象有:结节状、肿块状、斑片状、分叶征、毛刺征、支气管充气征或空泡征、胸膜凹陷征、血管集束征等.增强CT扫描周围型肺癌呈均匀或不均匀强化,CT值增幅约20~60 Hu,CT值增幅小于20 Hu则提示良性病变如结核球,CT值增幅大于60 Hu考虑炎性病变可能性大.结论 螺旋CT及增强CT扫描对周围型肺癌的诊断及鉴别诊断具有重要价值.%Objectives To study the diagnostic value of spiral CT scan on peripheral lung cancer. Methods 60 cases of Peripheral Lung Cancer that have been underwent Spiral CT Scan and confirmed by pathlogy were collected, and among them, 35 cases were performed with enhanced CT scan and their CT images were analyzed. Results The CT signs of Peripheral Lung Cancer are nodules, bump, patchy consolidation, the sub lobe drafts, the burr drafts the vacuole drafts, the bronchial tube gasification drafts, the pleural membrane drafts hollowly and the blood vessel gathers drafts. The results of enhanced CT scan on Peripheral Lung Cancer show homogeneous and non-homogeneous enhancement, and the increase amplitude of CT is about 20-60 Hu. When the increase amplitude is lower than 20Hu, it means benign lesions such as tuberculoma; when the increase amplitude is higher than 60Hu, it probably means inflammatory lesions. Conclusion The Spiral CT Scan and enhanced CT scan are of great significance in diagnosis and the differential-diagnosis.

  18. A retrospectively ECG-gated multislice spiral CT scan and reconstruction technique with suppression of heart pulsation artifacts for cardio-thoracic imaging with extended volume coverage

    A method for cardio-thoracic multislice spiral CT imaging with ECG gating for suppression of heart pulsation artifacts is introduced. The proposed technique offers extended volume coverage compared with standard ECG-gated spiral scan and reconstruction approaches for cardiac applications: Thin-slice data of the entire thorax can be acquired within one breath-hold period using a four-slice CT system. The extended volume coverage is enabled by a modified approach for ECG-gated image reconstruction. For a CT system with 0.5-s gantry rotation time, images are reconstructed with 250-ms image temporal resolution. Instead of selecting scan data acquired in exactly the same phase of the cardiac cycle for each image as in standard ECG-gated reconstruction techniques, the patient's ECG signal is used to omit scan data acquired during the systolic phase of highest cardiac motion. With this approach cardiac pulsation artifacts in CT studies of the aorta, of paracardiac lung segments, and of coronary bypass grafts can be effectively reduced. (orig.)

  19. Clinical study of spiral CT urography in the diagnosis of urinary tract disease in children

    Objective: To evaluate the ability of excretory CT urography (CTU) in the application of the upper urinary tract in children by comparing with intravenous urography (IVU) and magnetic resonance urography (MRU) , and to evaluate the value of CTU in the diagnosis of various diseases on upper urinary tract in children. Methods: Sixty-two children suspected with upper urinary tract disease were imaged by CTU, 31 of them underwent IVU, and 13 of them underwent MRU, Each urinary tract was arbitrarily divided into five parts (calices, pelvis, upper, middle, and lower ureters) for scoring of images on a five-point scale for opacification by contrast material. Opacification scores for the two groups (normal and abnormal) of urinary tracts were then compared. Compared with IVU and MRU, CTU was evaluated in the diagnosis of upper urinary tract disease in children. Results: The score of IVU and CTU was higher than that of MRU for all parts of the normal urinary tracts (P < 0.01) . The score of CTU was higher than that of IVU and MRU for calices and pelvis of the abnormal urinary' tracts (P < 0.01 ) . Differences in scores for upper ureter were not statistically significant among IVU, CTU, and MRU. The score of CTU and MRU was higher than that of IVU for middle and lower ureters (P < 0.01). The accurate rate of CTU in diagnosing renal duplication and renal hypoplasia was 100% , which was higher than that of IVU and MRU. In diagnosing the hydronephrosis, CTU (100%) and MRU (100%) were better than IVU (62.5%); CTU was also more reliable in detecting the ectopic ureteral orifice, ureterocele, and severe renal injury than IVU and MRU. Conclusion: CTU is a reliable technique for the diagnosis of urinary tract diseases. If a child was suspected to have each of the following diseases by ultrasound examination, such as renal duplication, renal hypoplasia, and severe renal injury, CTU could be selected as the first choice

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

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

    2009-01-01

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

  1. The capacity of spiral CT angiography in evaluation of the central pulmonary vascular involvement from central lug cancer

    Objective: To investigate the capacity of CTA including multiplanar reconstructions (MPR) and volume rendering technique (VRT) in evaluation of the central pulmonary vascular involvement from central lung cancer (CLC), and to compare with transverse image. Methods: In a prospective series, 52 spiral CT examinations were performed on a Picker 6000 scanner for suspected CLC. Contrast medium was injected at a rate of 4 ml/s with a power injector. The scanning delay was 20 seconds. The study volume was from the arch of the aorta to the inferior pulmonary veins done in a single breath-hold, using 3 mm collimation, pitch of 1.0 and reconstructed at 1 mm intervals. 6 patients without CLC were excluded. Three radiologists compared transverse image with CTA (MPR and VR) image in a blind way, and then the findings were compared with the surgical and pathological results. Results: Reconstructed image quality was graded as excellent (50.0%) or good (41.3%), whereas motion-related artifacts led to poor image quality in 8.7% of cases. In evaluating vascular encasement of CLC, CTA was more sensitive (97.3% vs 84.0%), specific (91.1% vs 89.3%), and accurate (94.7% vs 86.3%) than transverse images. The difference in sensitivity and accuracy was statistically significant (χ2 = 7.878, P = 0.005 and χ2 = 5.532, P = 0.019, respectively). Conclusions: CTA is a more useful imaging modality before pneumonectomy, especially in pulmonary artery reconstruction and in extended resection for locally advanced lung cancer particularly when cardiopulmonary bypass is needed

  2. The influence of motion artifacts conditioned by reconstruction, on the coronary calcium score in multislice spiral CT

    Purpose: A major problem of the quantification of coronary calcifications is a high variability of the coronary calcium score between recurrent examinations and different observers. Aim of our study is to evaluate the influence of different RR-intervals on the coronary calcium score utilizing retrospectively gated multislice spiral CT (MSCT) data sets. Materials and Method: 50 consecutive patients underwent MSCT examination (Somatom Volume Zoom, Siemens, Forchheim, G) utilizing a standardized scan protocol (4 x 2.5 mm collimation, 3 mm increment, tube current 133 mAs, tube voltage 120 kV). Retrospectively gated image reconstruction was performed every 10% of the RR interval. Coronary calcification was evaluated by the Agatston score. Coronary risk assessment was performed in all patients with image reconstruction beginning at 80% of the RR interval. The reconstruction intervals with the least motion artifacts were identified and chosen as reference for a reevaluation of the coronary risk. The results of different reconstruction times were compared. Results: The mean calcium score was 551.6. The calcium score varied between 512.2 (90%) and 571.7 (70%), depending on the image reconstruction interval. Compared to the mean calcium score a new classification of the coronary risk was necessary in 7/50 of the patients at 80% reconstruction interval, and in 2/50 of the patients at 50% of the RR interval, respectively. Conclusion: Movement of the coronary arteries at different image reconstruction intervals has an important influence on the coronary calcium score. Based on our data, we propose image reconstruction at 50% of the RR interval for evaluation of the coronary calcium score by MSCT. (orig.)

  3. Diagnosis of bronchiectasis with multislice spiral CT: accuracy of 3-mm-thick structured sections

    The aim of this study was to evaluate the accuracy of 3-mm-thick reconstructed sections in the diagnosis of bronchiectasis with multislice CT (MSCT). Forty consecutive patients suspected of bronchiectasis (23 females, 17 males; mean age 51 years) underwent MSCT of the entire thorax with a 4 x 1-mm collimation (120 kV, 0.5 s/rotation, 80 mAs/slice) and a pitch of 1.75. From each data set (mean z-axis coverage: 257 mm; mean duration: 21 s), two series of images were systematically generated: 1-mm (group 1) and 3-mm (group 2)-thick reconstructed scans. Both series of images were obtained at 10-mm intervals and reconstructed with a high-spatial-frequency algorithm. Two observers independently analyzed the presence of bronchiectasis and associated abnormalities in group-1 and group-2 lung images. No significant difference between group 1 and group 2 was found in: (a) the detection of bronchiectasis, identified in 24 patients (60%) in group 1 and in 23 patients (57.5%) in group 2 (p=0.08); (b) the evaluation of the extent of bronchiectasis, identifying focal bronchiectasis in 10 patients (25%) in group 1 and 7 patients (17.5%) in group 2 (p=0.39) and multifocal bronchiectasis in 16 patients (40%) in both groups; (c) the characterisation of bronchiectasis (cylindral bronchiectasis: group 1, n=24, 60%; group 2, n=21, 53%, p=0.08); varicose bronchiectasis: group 1, n=5, 12.5%; group 2, n=6, 15%, p=0.56; and cystic bronchiectasis: group 1, n=2, 5%; group 2, n=2, 5%. Apart from the identification of abnormal bronchial wall thickening (group 2, n=35, 87.5%, vs group 1, n=31, 77.5%, p<0.05), recognition of associated bronchopulmonary anomalies did not differ between the two groups. This study demonstrates a comparable accuracy of the 3- and 1-mm-thick reconstructed scans in the detection and characterization of bronchiectasis. These results suggest the potential usefulness of 3-mm-thick scans generated from 4 x 2.5-mm acquisitions in the screening of bronchiectasis, which would

  4. Left ventricular functional parameters: comparison of 16-slice spiral CT with MRI

    Purpose: the quantitative measurement of left ventricular functional parameters using multislice computed tomography (MSCT) with retrospective ECG-gating and comparison of the results with magnetic resonance imaging (MRI). Materials and methods: thirty-one patients with suspected or known coronary artery disease underwent MSCT angiography with retrospective ECG-gating (Sensation 16, Siemens). Based on the CT data set, short axis reformations of the left ventricle were performed for functional analysis. On a commercially available workstation, end-diastolic-(EDV), end-systolic- (ESV), stroke volume (SV), ejection fraction (EF) and myocardial mass (MM) were calculated from MSCT (temporal resolution 105-210 ms) data according to the modified Simpson's rule and compared to MRI (1.5 T scanner, temporal resolution 48 ms) using a 2D TrueFISP cine sequence with respiration hold. Results: in all cases, the quality was adequate for both MSCT and MRI. MSCT and MRI had an excellent correlation for EDV (r = 0.86), ESV (r = 0.91), EF (r = 0.87) and MM (r = 0.88), and a good correlation for SV (r = 0.70). The mean difference was 13.2±21.9 ml for EDV, 8.7±15.9 ml for ESV, 4.6±12.3 ml for SV, 1.4±5.2% for EF, and 11.9±13.8 g for MM. However, EDV (p = 0.002), ESV (p = 0.005), SV (p = 0.048), and MM (p < 0.0001) were significantly overestimated with MSCT compared to MRI. For EF, no significant difference between MSCT and MRI was found (p = 0.15). Conclusion: for left ventricular functional parameters, MSCT of the heart with retrospective ECG-gating showed a high correlation with MRI, which has an important implication when using MSCT for non-invasive cardiac imaging. Despite the high correlation, overestimation of EDV, EVS, SV, and MM with MSCT has to be taken into account when applying this technology in clinical practice. EF was not significantly different between both modalities. (orig.)

  5. Spiral CT dual-phase scanning for hepatocellular carcinoma: comparison study on the peripheral enhancement and pathology

    Objective: To compare the peripheral enhancement features of hepatocellular carcinoma (HCC) lesions in arterial and portal venous phases with histopathology, and to study the histopathologic bases of peripheral enhancement of the HCC lesions and how it affects the biologic behavior and prognosis. Methods: Forty-two histopathologically proven HCC patients were included. First, an unenhanced scanning covering the whole liver was done, and followed by arterial and portal venous phase scanning. The delay time was 20 sec and 60 sec after the injecting of contrast media. the slides of 5 μm thickness were stained with HE and the standard immunoperoxidase method using the polyclonal antibody of factor VIII-related antigen (F8RA). The pseudo capsule of the lesion, tumor invasion of the pseudo capsule, and the number of positive stained tumor vessels in the pseudo capsule were evaluated. Results: Among the 42 cases, in arterial phase, the pseudo capsule of the HCC lesions was demonstrated as hyper-or hypo-attenuation in 13 and 8 cases, respectively, and no marked pseudo capsule was perceived in 21 cases. In portal venous phase, hyper-attenuated pseudo capsule was shown in 27 cases, hypo-attenuated pseudo capsule in 2 cases, and no pseudo capsule in 13 cases. On CT scans, daughter foci were showed in 14 cases, in which 9 cases were single and 5 of 42 patients, and tumor cells invaded the pseudo capsule in 16 caes among these cases. F8RA immunohistochemical staining showed that the pseudo capsule contained rich positive staining neo-vascular structure in 15 of 25 cases, and the other 10 cases had thick pseudo capsule but few neo-vascular structure. HE staining showed no marked pseudo capsule in 17 cases, in which 8 cases exhibited no clear border between the tumor tissue and liver parenchyma. Conclusion: The peripheral enhancement features of HCC on spiral CT dural-phase scanning could reflect the histopathologic characteristics and predict the biologic behavior and prognosis

  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

    contrast agent was 19% or 38%,no pseudo-color map was created.The viscosity increased when the concentration of the contrast agent was 76%; so it is difficult to inject the contrast agent at such a high concentration.Also no pseudo-color map was generated when the injection time was short (1,2-3,and 4-5 seconds)or the injection rate was low (0.3 mi/s).The best perfusion images and perfusion parameters were obtained during 50 seconds scanning.Each rat was given an injection of 57% diatrizoate at 0.5 mi/s via the tail vein using a high-pressure syringe for 6 seconds.The perfusion parameters included hepatic blood flow (HBF),hepatic blood volume (HBV),mean transit time (MTT) of the contrast agent,capillary permeability-surface area product (PS),hepatic arterial index (HAI),hepatic artery perfusion (HAP),and hepatic portal perfusion (HPP).All these parameters reflected the perfusion status of liver parenchyma in normal rats,Three phases of enhancement were modified according to the time-density curves (TDCs) of the perfusion imaging:hepatic arterial phase (7 seconds),hepatic portal venous phase (15 seconds),and a delayed phase (23-31 seconds).On examination by microscopy,the liver tissues were pathologically normal.Conclusions The appropriate protocol with multi-slice spiral CT liver perfusion reflected normal liver hemodynamics in rats.This study laid a solid foundation for further investigation of the physiological characteristics of liver cancer in a rat model,and was an important supplement to and reference for conventional contrast-enhanced CT scans.

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

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

  8. 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

  9. Coronary CT angiography using 64 detector rows: methods and design of the multi-centre trial CORE-64

    Multislice computed tomography (MSCT) for the noninvasive detection of coronary artery stenoses is a promising candidate for widespread clinical application because of its non-invasive nature and high sensitivity and negative predictive value as found in several previous studies using 16 to 64 simultaneous detector rows. A multi-centre study of CT coronary angiography using 16 simultaneous detector rows has shown that 16-slice CT is limited by a high number of nondiagnostic cases and a high false-positive rate. A recent meta-analysis indicated a significant interaction between the size of the study sample and the diagnostic odds ratios suggestive of small study bias, highlighting the importance of evaluating MSCT using 64 simultaneous detector rows in a multi-centre approach with a larger sample size. In this manuscript we detail the objectives and methods of the prospective ''CORE-64'' trial (''Coronary Evaluation Using Multidetector Spiral Computed Tomography Angiography using 64 Detectors''). This multi-centre trial was unique in that it assessed the diagnostic performance of 64-slice CT coronary angiography in nine centres worldwide in comparison to conventional coronary angiography. In conclusion, the multi-centre, multi-institutional and multi-continental trial CORE-64 has great potential to ultimately assess the per-patient diagnostic performance of coronary CT angiography using 64 simultaneous detector rows. (orig.)

  10. Coronary CT angiography using 64 detector rows: methods and design of the multi-centre trial CORE-64

    Miller, Julie M.; Vavere, Andrea L.; Arbab-Zadeh, Armin; Bush, David E.; Lardo, Albert C.; Texter, John; Brinker, Jeffery; Lima, Joao A.C. [Johns Hopkins Hospital, Johns Hopkins University, Department of Medicine, Division of Cardiology, Baltimore, MD (United States); Dewey, Marc [Charite - Universitaetsmedizin Berlin, Medical School, Humboldt-Universitaet und Freie Universitaet zu Berlin, Department of Radiology, Berlin, PO Box 10098 (Germany); Rochitte, Carlos E.; Lemos, Pedro A. [University of Sao Paulo Medical School, Heart Institute (InCor), Sao Paulo (Brazil); Niinuma, Hiroyuki [Iwate Medical University, Department of Cardiology, Morioka (Japan); Paul, Narinder [Toronto General Hospital, Department of Medical Imaging, Toronto (Canada); Hoe, John [Medi-Rad Associates Ltd, CT Centre, Mt Elizabeth Hospital, Singapore (Singapore); Roos, Albert de [Leiden University Medical Center, Department of Radiology, Leiden (Netherlands); Yoshioka, Kunihiro [Iwate Medical University, Department of Radiology, Morioka (Japan); Cox, Christopher [Johns Hopkins Bloomberg School of Public Health, Department of Epidemiology, Baltimore, MD (United States); Clouse, Melvin E. [Harvard University, Department of Radiology, Beth Israel Deaconess, Boston, MA (United States)

    2009-04-15

    Multislice computed tomography (MSCT) for the noninvasive detection of coronary artery stenoses is a promising candidate for widespread clinical application because of its non-invasive nature and high sensitivity and negative predictive value as found in several previous studies using 16 to 64 simultaneous detector rows. A multi-centre study of CT coronary angiography using 16 simultaneous detector rows has shown that 16-slice CT is limited by a high number of nondiagnostic cases and a high false-positive rate. A recent meta-analysis indicated a significant interaction between the size of the study sample and the diagnostic odds ratios suggestive of small study bias, highlighting the importance of evaluating MSCT using 64 simultaneous detector rows in a multi-centre approach with a larger sample size. In this manuscript we detail the objectives and methods of the prospective ''CORE-64'' trial (''Coronary Evaluation Using Multidetector Spiral Computed Tomography Angiography using 64 Detectors''). This multi-centre trial was unique in that it assessed the diagnostic performance of 64-slice CT coronary angiography in nine centres worldwide in comparison to conventional coronary angiography. In conclusion, the multi-centre, multi-institutional and multi-continental trial CORE-64 has great potential to ultimately assess the per-patient diagnostic performance of coronary CT angiography using 64 simultaneous detector rows. (orig.)

  11. Historical review on the development of computed tomography on the occasion of putting a new spiral CT into operation at the University of Veterinary Medicine, Vienna

    Linear tomography has been well known since the thirties of the last century. Before and alter World War II attempts of taking cross sections were done radiographically, but image quality was extremely poor. About 1960 A.M. Cormack developed a possibility to measure body densities for radiation therapy. After having attempted digitization of x-ray intensities during tissue penetration, G.N. Hounsfield constructed the first scanner in 1972 - in the first run only to examine the head. Improvements of technology lead to a series of generations of scanners which ended in the development of spiral CT and multi-slice detectors. In veterinary medicine the first papers on the use of CT in small animals were published by clinicians in the United States and in Germany nearly at the same time in 1980. A number of reports appeared afterwards from clinicians worldwide. The technique for examination of the horse was first described in the United States in 1986; in Europe the first CT scanner examining horses was established in Utrecht. At the Radiology Clinic of the University of Veterinary Medicine, Vienna, the first scanner for clinical use started to operate in summer 1993. The diagnostic possibilities improved in 1997 by introduction of a large animal weight bearing table. A new spiral CT has been put into operation in February 2001. CT has dramatically improved diagnostic accuracy in diagnostic imaging and lead to advanced therapy and prognosis for the patient in many specialist fields of veterinary medicine, e.g. neurosurgery, neurology, oncology, or orthopedics. (author)

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

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

    2010-01-01

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

  13. Value of negative spiral CT angiography in patients with suspected acute PE: analysis of PE occurrence and outcome

    Krestan, C.R.; Klein, N.; Fleischmann, D.; Kaneider, A.; Kreuzer, S.; Riedl, C.; Herold, C.J. [Department of Radiology, University Hospital of Vienna-AKH, Waehringer Guertel 18-20, 1090, Vienna (Austria); Novotny, C. [Department of Nuclear Medicine, University Hospital of Vienna-AKH, Waehringer Guertel 18-20, 1090, Vienna (Austria); Minar, E. [Division of Angiology, Department of Internal Medicine, University Hospital of Vienna-AKH, Waehringer Guertel 18-20, 1090, Vienna (Austria); Janata, K. [Department of Emergency Medicine, University Hospital of Vienna-AKH, Waehringer Guertel 18-20, 1090, Vienna (Austria)

    2004-01-01

    The aim of this study was to analyze pulmonary embolism (PE) occurrence and retrospective clinical outcome in patients with clinically suspected acute PE and a negative spiral CT angiography (SCTA) of the pulmonary arteries. Within a 35-month period, 485 consecutive patients with clinical symptoms of acute PE underwent SCTA of the pulmonary arteries. Patients with a negative SCTA and without anticoagulation treatment were followed-up and formed the study group. Patient outcome and recurrence of PE was evaluated retrospectively during a period of 6 months after the initial SCTA, and included a review of computerized patient records, and interviews with physicians and patients. Patients were asked to fill out a questionnaire concerning all relevant questions about their medical history and clinical course during the follow-up period. Special attention was focused on symptoms indicating recurrent PE, as well as later confirmation and therapy of PE. Of the 485 patients, 325 patients (67%) had a negative scan, 134 (27.6%) had radiological signs of PE, and 26 (5.4%) had an indeterminant result. Of 325 patients with a negative scan, 269 (83%) were available for follow-up. The main reasons for loss to follow-up were change of address, name, or phone number, or non-resident patients who left abroad. Of 269 patients available for follow-up, 49 patients (18.2% of 269) received anticoagulant treatment because of prior or recent deep venous thrombosis (32.6%) or a history of PE (34.7%), cardiovascular disease (18.4%), high clinical probability (8.2%), positive ventilation-perfusion scan (4.2%), and elevated D-dimer test (2%). The remaining 220 patients, who did not receive anticoagulant medication, formed the study group. Of this study group, 1 patient died from myocardial infarction 6 weeks after the initial SCTA, and the postmortem examination also detected multiple peripheral emboli in both lungs (p=0.45%; 0.01-2.5, 95% confidence interval). The PE did not occur in any other

  14. 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)

  15. To Investigate the Application of Spiral CT Three-dimensional Reconstruction of the Value of Calcaneal Fractures%跟骨骨折应用螺旋 CT 三维重建的价值探讨

    李海源; 李小满; 高莉丽; 林秀琼; 蔡映红; 梁玉英

    2015-01-01

    Objective Analysis of spiral CT three-dimensional reconstruction imaging in the diagnosis of trauma in the clinical value of calcaneus .Methods Collection the patients with calcaneal injury to our hospital for diagnosis and treatment in November 2 0 1 2 to November 2 0 1 4 ,selection of image data w hich patients had X-ray examination and three-dimensional reconstruction of spiral CT examination ,comparison of X -ray and spiral CT 3 D reconstruction ,by using the SPSS1 9 .0 statistical software using chi square test analysis of the dif-ference between X-ray and spiral CT 3 D reconstruction in diagnosis ,classification of calcaneal fracture .Results X-ray examination and CT 3 D reconstruction for diagnosis if there is no statistical significance of calcaneal fracture(P=0 .371 >0 .05 ) ,the fracture type classification (comminuted ,intra-articular) are highly statisti-cally significant( P<0 .0 1 ) .Conclusion X-ray and spiral CT 3 D reconstruction is the basic way to check the calcaneum bone fracture ,but the spiral CT three-dimensional reconstruction can specifically form more intu-itive ,comprehensive ,clear observation of fracture ,bring convenience for Department of orthopedics diagnosis and treatment .%目的:分析螺旋CT三维重建成像技术在诊断跟骨外伤中临床价值。方法收集2012年11月至2014年11月间到我院接受诊治的跟骨外伤患者,挑选其中患者均有进行X线平片检查及螺旋CT三维重建检查的影像资料,比较X线平片检查及螺旋CT三维重建,采用SPSS 19.0统计软件应用卡方检验分析X线平片检查及螺旋CT三维重建对跟骨骨折诊断、分类的差异。结果 X线平片检查与CT三维重建对于诊断是否有跟骨骨折无统计学意义(P=0.371>0.05),对于骨折类型分类(粉碎性、关节内)有高度统计学意义( P<0.01)。结论 X线平片检查及螺旋CT三维重建都是跟骨骨折检查的基本方式,但螺旋CT三维重

  16. Intravenous spiral CT angiography for assessment before orthotopic liver transplantation: Comparison between tomography, MIP, 3-dimensional surface imaging and intraarterial DSA

    Purpose: To analyse the efficacy of intravenous spiral CT angiography (SCTA) for the evaluation before orthotopic liver transplantation (oLT) compared with DSA. Methods: Spiral CT was performed on 31 potential recipients of a liver graft in order to examine hepatic vessels, coeliac axis, splenic artery and superior mesenteric artery. The arterial vessels were reconstructed in 'Maximum Intensity Projection (MIP)' and 'Shaded Surface Display (SSD)'-technique. The axial images, MIP and SSD were compared in 25 patients with DSA with regard to the visualisation of the vascular anatomy, detectability of stenosis and vascular diameters. Results: The type of arterial liver supply could be determined via SCTA in all patients. Stenosis of the coeliac axis was seen in ten patients on the DSA, MIP and SSD and in eight patients on the axial images. Occlusion of the hepatic artery was clearly visualised in two patients on the DSA, axial images and MIP and in one patient on the SSD. There was no false positive diagnosis with SCTA. SSD was seen as the best technique to visualise the vessels without overshadowing. There were no significant differences between the diamters measured from the axial images, MIP and SSD images in transversal direction and the DSA images (p>0.05). Conclusion: SCTA is a greatly promising method for the imaging of vessels supplying the liver before oLT, and may convey more diagnostic information than DSA. (orig.)

  17. Spiral-CT assisted detection and quantification of pulmonary reaction in breast cancer patients treated with cobalt- or linac megavoltage radiation therapy

    Object : The aim of the study is to sensitively detect and quantify the irradiation induced pulmonary side effects in breast cancer patients, using the quantitative spiral-CT analysis. Material and Method : We prospectively investigated 48 patients at an average of 62 yrs. on pulmonary reactions after postopera-tive radiotherapy on mamma carcinoma. The patients were treated with either tangential thoracic fields alone (26 pat) or tangents with additional opposing ap/pa-fields to the supraclavicular(sc) and axillary(ax) region(18 pat) or tangents and sc-ax-fields with an additional parasternal or dorsal field(4 pat). 44 patients underwent irradiation at the 1MV cobalt with 50Gy, while 4 patients were irradiated at the 6MV linac with 50Gy. Quantitative spiral chest-CT was performed before radiotherapy and six(6), respectively twelve(12) weeks after therapy. Using the 'region of interest (RoI)' technique, the peripheral, subpleural and apical lung parenchyma on corresponding slices of the pretherapeutic- and the follow-up chest-CT's was examined according to its' density and volume changes. Especially, the quantitative spiral-CT marks an distinct advantage, allowing the complete reception of the examined lung volume without skipping a slice because of patient's breathing. Results : While the lung regions, within the treatment volume of the tangents showed an average density increase of 10% ±6% at 6 weeks, respectively of 15% ±8% at 12 weeks after radiotherapy, there was only a minor increase at the apical parenchyma, irradiated with the sc-ax fields of 7% ±4%, respectively 10% ±5%. Two patients, receiving a parasternal field demonstrated a sharp density gain of 24% ±7% and 29% ±8%. There were no clinical symptoms suggesting a radiation pneumonitis. An age related density increase could be observed, revealing a gain of 12% ±7% in those patients older than 60 yrs (28pat), while in the younger group (20pat) the rise was 8% ±5%. Regarding the functional lung

  18. Dual-source spiral CT with pitch up to 3.2 and 75 ms temporal resolution: Image reconstruction and assessment of image quality

    Flohr, Thomas G.; Leng Shuai; Yu Lifeng; Allmendinger, Thomas; Bruder, Herbert; Petersilka, Martin; Eusemann, Christian D.; Stierstorfer, Karl; Schmidt, Bernhard; McCollough, Cynthia H. [Siemens Healthcare, Computed Tomography, 91301 Forchheim, Germany and Department of Diagnostic Radiology, Eberhard-Karls-Universitaet, 72076 Tuebingen (Germany); Department of Radiology, Mayo Clinic, Rochester, Minnesota 55905 (United States); Siemens Healthcare, Computed Tomography, 91301 Forchheim (Germany); Department of Radiology, Mayo Clinic, Rochester, Minnesota 55905 (United States)

    2009-12-15

    Purpose: To present the theory for image reconstruction of a high-pitch, high-temporal-resolution spiral scan mode for dual-source CT (DSCT) and evaluate its image quality and dose. Methods: With the use of two x-ray sources and two data acquisition systems, spiral CT exams having a nominal temporal resolution per image of up to one-quarter of the gantry rotation time can be acquired using pitch values up to 3.2. The scan field of view (SFOV) for this mode, however, is limited to the SFOV of the second detector as a maximum, depending on the pitch. Spatial and low contrast resolution, image uniformity and noise, CT number accuracy and linearity, and radiation dose were assessed using the ACR CT accreditation phantom, a 30 cm diameter cylindrical water phantom or a 32 cm diameter cylindrical PMMA CTDI phantom. Slice sensitivity profiles (SSPs) were measured for different nominal slice thicknesses, and an anthropomorphic phantom was used to assess image artifacts. Results were compared between single-source scans at pitch=1.0 and dual-source scans at pitch=3.2. In addition, image quality and temporal resolution of an ECG-triggered version of the DSCT high-pitch spiral scan mode were evaluated with a moving coronary artery phantom, and radiation dose was assessed in comparison with other existing cardiac scan techniques. Results: No significant differences in quantitative measures of image quality were found between single-source scans at pitch=1.0 and dual-source scans at pitch=3.2 for spatial and low contrast resolution, CT number accuracy and linearity, SSPs, image uniformity, and noise. The pitch value (1.6{<=}pitch{<=}3.2) had only a minor impact on radiation dose and image noise when the effective tube current time product (mA s/pitch) was kept constant. However, while not severe, artifacts were found to be more prevalent for the dual-source pitch=3.2 scan mode when structures varied markedly along the z axis, particularly for head scans. Images of the moving

  19. The study of diagnostic accuracy of prospectively electrocardiogram-triggered high-pitch spiral acquisition using Flash dual-sources CT for the assessment of coronary stenoses

    Objectives: To prospectively investigate the diagnostic accuracy,image quality and radiation doses of prospectively ECG-triggered high-pitch spiral acquisition computed tomography coronary angiography (CTCA) using Flash dual-source CT for the diagnosis of significant coronary stenoses. Methods: Seventy-three patients underwent both CTCA and CCA. CTCA was performed using a Flash dual-source CT system with data acquisition at a high-pitch of 3.4. CCA served as the standard of reference. Radiation dose values were calculated using the dose-length product. Results: There were 925 vessel segments in 73 patients. (1) Diagnostic accuracy: the sensitivity, specificity and positive and negative predictive values were 93.2% (164/176), 96.4% (722/749), 85.9% (164/191), 98.4% (722/734) for segment assessment and 98.4% (123/125), 87.4% (83/95), 91.1% (123/135), 97.6% (83/85) for vessel assessment and 100% (44/44), 89.7% (26/29), 93.6% (44/47), 100% (26/26) for patient assessment. (2) Image quality: there were 2 coronary segments of right coronary artery and one segment of left circumflex artery with non-diagnostic image quality. There was no non-diagnostic image quality in left anterior descending artery. (3) Radiation dose: the effective radiation dose was (1.14 ± 0.10) mSv. Conclusions: CTCA using the prospectively ECG-triggered high-pitch spiral mode of the Flash dual-source CT system is associated with high diagnostic accuracy for the assessment of coronary artery stenoses at low dose. (authors)

  20. The role of whole body spiral CT in the primary work-up of polytrauma patients - comparison with conventional radiography and abdominal sonography; Die Rolle der Ganzkoerper-Spiral-CT bei der Primaerdiagnostik polytraumatisierter Patienten - Vergleich mit konventioneller Radiographie und Abdomensonographie

    Albrecht, T.; Schlippenbach, J. von; Wolf, K.J. [Klinik und Poliklinik fuer Radiologie und Nuklearmedizin, Charite - Campus Benjamin Franklin (Germany); Stahel, P.F.; Ertel, W. [Klinik fuer Unfall- und Wiederherstellungschirurgie, Charite - Campus Benjamin Franklin (Germany)

    2004-08-01

    Purpose: To evaluate the role of routine 'whole body spiral CT' in the primary work-up of polytrauma patients for injuries of the thorax, abdomen and spine, and to compare the results with those of conventional radiography of the chest and spine and abdominal ultrasound. Materials and Methods: Fifty consecutive polytrauma patients underwent contrast-enhanced single slice spiral CT (5 mm collimation) from the vertex to the floor of the pelvis as part of the primary work-up after emergency room admission. Overlapping high resolution sections and sagittal reformations of the spine were obtained. Reports of additional chest radiographs (n=43), abdominal ultrasound examinations (n=47) and spine radiographs (n=36) performed in the emergency room were available for retrospective comparison. The 'final diagnoses', which served as the standard of reference, were taken from the patients' records using all information that became available until discharge or death, such as findings from further imaging, surgery and autopsy. Results: CT showed 109 (97%) of 112 thoracic and abdominal soft-tissue injuries. Relevant injuries missed were an early splenic laceration and an early pelvic hematoma, both of which became clinically apparent several hours later. There were 4 false positive CT findings. Conventional chest radiography demonstrated only 20% of thoracic and sonography 22% of abdominal injuries. Chest radiography and sonography produced 2 false-positive findings each. CT showed 66 (87%) of 76 vertebral fractures including all 19 unstable ones. CT missed 5 anterior vertebral body and 5 spinous/transverse process fractures. Conventional radiography found 71% of vertebral fractures including only 50% of the unstable one. (orig.)

  1. Clinical evaluation of ventilation-perfusion scintigraphy and spiral CT angiography in the diagnosis of pulmonary embolism

    Objective: To evaluate the clinical capability of ventilation-perfusion (V-P) scintigraphy and spiral CT angiography (SCTA) in the diagnosis of pulmonary embolism (PE). Methods: The study was performed in 65 consecutive patients with suspected PE who underwent both V-P scintigraphy and SCTA. There were 43 men and 22 women aged 25-78 years (mean, 60.1 years). Averaged interval between V-P scintigraphy and SCTA was 2.6+0.7 days, and non anticoagulation was taken between the two tests. Of the 65 patients, angiography was also performed in 8. V-P scintigraphy was performed by using a SPECT equipped with parallel-hole, low-energy, all-purpose collimator. Both perfusion and ventilation images were acquired in eight projections. First, perfusion images were acquired with 500,000 counts per view after intravenous administration of 185 MBq of Tc-99m macroaggregated serum albumin. If perfusion imaging is normal, examination would be ended. When abnormality was found on perfusion imaging, ventilation images were followed with 400,000 counts per view after administration of 370 MBq of Tc-99m diethylenetriaminepentaacetic acid aerosol. V-P scintigrams are classified as normal, or low, intermediate or high probability of PE by using a modification of the diagnostic criteria, according to the PIOPED study. In this study, normal or low probability of PE is considered as negative, high probability of PE, as positive and intermediate probability of PE, as non-diagnostic. SCTA examinations were performed at 120 kVp and 200- 250 mA with 4-mm-thinck section and a pitch of 3. All scans were obtained in a caudocraninal direction, starting at the level of the lower hemi diaphragm and ending at the top of the aortic arch, with a breath holding lasted from 20 to 30 seconds. Images were reconstructed at l.5 intervals with a standard reconstruction algorithm. Patients received 80-100 ml of 60% iodinated contrast material administered through an automated injector. Images were analyzed with

  2. 44例儿童气道螺旋CT冠状扫描技术探讨%The coronal scans technique of spiral CT on children's airway

    刘先凡; 何玲

    2011-01-01

    目的 探讨儿童气道螺旋CT冠状扫描体位与成像效果的关系.方法 回顾分析2008年7~12月44例气道螺旋CT冠状扫描影像资料,结合体位的设置及测量扫描线与气管长轴的角度探讨冠状扫描的气道显示效果.结果 气道显示效果佳者33例,扫描线基本与气道平行,最大角度小于2°;效果一般者8例,扫描线与气道成5~10°角;效果差者3例,扫描线与气道角度大于12°.结论 螺旋CT冠状扫描显示儿童气道全程佳,体位的设置直接影响气道全程的显示效果.%Objective To explore the relation of imaging effect and coronal scan position of spiral CT on children's airway. Methods Reviewed the images of spiral CT coronal scan on the 44 cases from July to December, 2008,to explore the airway show effect of coronal scan to combine the position design and measurement the angle of scan line and air way long axial. Results The effect of airway showed well in 33 cases,with the scan line parallel airway,the largest angle <2°, common in 8 cases with the scan line were angled 5-10° with airway,bad in 3 cases with the scan line were angled >12° with airway. Conclusion The airway show of children are well with spiral CT coronal scan,the scan position to direct affect the view effect of airway.

  3. Diagnostic image quality of a comprehensive high-pitch dual-spiral cardiothoracic CT protocol in patients with undifferentiated acute chest pain

    Bamberg, Fabian, E-mail: fbamberg@med.lmu.de [Department of Clinical Radiology, Ludwig-Maximilians University, Klinikum Grosshadern, Munich (Germany); Marcus, Roy; Sommer, Wieland; Schwarz, Florian; Nikolaou, Konstantin; Becker, Christoph R.; Reiser, Maximilian F.; Johnson, Thorsten R.C. [Department of Clinical Radiology, Ludwig-Maximilians University, Klinikum Grosshadern, Munich (Germany)

    2012-12-15

    Objective: To evaluate diagnostic image quality of high-pitch dual source comprehensive cardiothoracic CT protocol in patients presenting with acute undifferentiated chest pain. Materials and methods: Consecutive symptomatic subjects (n = 51) with undifferentiated acute chest pain underwent ECG-synchronized high-pitch dual-spiral chest CT angiography (Definition Flash, Siemens Medical Solutions, 2 × 100 kVp or 2 × 120 kV if BMI > 30, collimation: 128 × 0.6 mm, pitch: 3.2). Independent investigators determined the image quality of each cardiac and pulmonary vessel segment, measured contrast-to-noise-ratio (CNR), and determined radiation exposure. In addition, the prevalence of CT findings (pulmonary embolism (PE), aortic dissection (AD) and significant coronary stenosis (≥50%)) was determined. Univariate and multivariate analysis were performed to determine the subpopulation with highest diagnostic quality. Results: Among 51 subjects (66% male, average age: 63 ± 15.8), the prevalence of positive CT findings was moderate (overall: 11.7%). Overall, image quality of the pulmonary, aortic and coronary vasculature was good (1.26 ± 0.43 and CNR: 2.52) with an average radiation dose of 3.82 mSv and 3.2% of segments rated non-evaluable. The image quality was lowest in the coronary arteries (p = 0.02), depending on the heart rate (r = 0.52, p < 0.001). In subjects with a heart rate of ≤65 bpm (n = 30) subjective image quality and CNR of the coronary arteries were higher (1.6 ± 0.5 vs. 2.1 ± 0.5, p = 0.03 and 1.21 ± 0.3 vs. 1.02 ± 0.3, p = 0.05) with only 1.5% segments classified as non-evaluable. Conclusion: High-pitch dual-spiral comprehensive cardiothoracic CT provides low radiation exposure with excellent image quality at heart rates ≤65 bpm. In subjects with higher heart rates, image quality of the aortic and pulmonary vasculature remains excellent, while the assessment of the coronary arteries degrades substantially.

  4. Diagnostic image quality of a comprehensive high-pitch dual-spiral cardiothoracic CT protocol in patients with undifferentiated acute chest pain

    Objective: To evaluate diagnostic image quality of high-pitch dual source comprehensive cardiothoracic CT protocol in patients presenting with acute undifferentiated chest pain. Materials and methods: Consecutive symptomatic subjects (n = 51) with undifferentiated acute chest pain underwent ECG-synchronized high-pitch dual-spiral chest CT angiography (Definition Flash, Siemens Medical Solutions, 2 × 100 kVp or 2 × 120 kV if BMI > 30, collimation: 128 × 0.6 mm, pitch: 3.2). Independent investigators determined the image quality of each cardiac and pulmonary vessel segment, measured contrast-to-noise-ratio (CNR), and determined radiation exposure. In addition, the prevalence of CT findings (pulmonary embolism (PE), aortic dissection (AD) and significant coronary stenosis (≥50%)) was determined. Univariate and multivariate analysis were performed to determine the subpopulation with highest diagnostic quality. Results: Among 51 subjects (66% male, average age: 63 ± 15.8), the prevalence of positive CT findings was moderate (overall: 11.7%). Overall, image quality of the pulmonary, aortic and coronary vasculature was good (1.26 ± 0.43 and CNR: 2.52) with an average radiation dose of 3.82 mSv and 3.2% of segments rated non-evaluable. The image quality was lowest in the coronary arteries (p = 0.02), depending on the heart rate (r = 0.52, p < 0.001). In subjects with a heart rate of ≤65 bpm (n = 30) subjective image quality and CNR of the coronary arteries were higher (1.6 ± 0.5 vs. 2.1 ± 0.5, p = 0.03 and 1.21 ± 0.3 vs. 1.02 ± 0.3, p = 0.05) with only 1.5% segments classified as non-evaluable. Conclusion: High-pitch dual-spiral comprehensive cardiothoracic CT provides low radiation exposure with excellent image quality at heart rates ≤65 bpm. In subjects with higher heart rates, image quality of the aortic and pulmonary vasculature remains excellent, while the assessment of the coronary arteries degrades substantially.

  5. 螺旋 CT动态增强扫描在肺门肿瘤立体适形放射治疗中的价值%The value of spiral CT dynamically enhanced scanning in steric shape-fitting radiotherapy of hilar tumors

    2001-01-01

    Objective To judge hilar tumors and their involvement range and improve the ability for the 3D plan of steric shape- fitting radiotherapy of pulmonary cancer dicide target area.Method Spiral CT dynamically enhanced scanning was used to localize the target area and distinguish pilar tumors,atelactasis,pilar blood vessels and enlarged lymphoid tissues,and define locus and involvement area.Result Local contour showed by spiral CT enhanced dynamically scanning was superior to that by common CT.Conclusion Spiral CT dynamically enhanced scanning is an ideal simulation for 3D conformal radiotherapy.

  6. Diagnostic efficacy of gadoxetic acid (Primovist)-enhanced MRI and spiral CT for a therapeutic strategy: comparison with intraoperative and histopathologic findings in focal liver lesions

    A multicenter study has been employed to evaluate the diagnostic efficacy of magnetic resonance imaging (MRI) using the new liver-specific contrast agent gadoxetic acid (Gd-EOB-DTPA, Primovist), as opposed to contrast-enhanced biphasic spiral computed tomography (CT), in the diagnosis of focal liver lesions, compared with a standard of reference (SOR). One hundred and sixty-nine patients with hepatic lesions eligible for surgery underwent Gd-EOB-DTPA-enhanced MRI as well as CT within 6 weeks. Pathologic evaluation of the liver specimen combined with intraoperative ultrasound established the SOR. Data sets were evaluated on-site (14 investigators) and off-site (three independent blinded readers). Gd-EOB-DTPA was well tolerated. Three hundred and two lesions were detected in 131 patients valid for analysis by SOR. The frequency of correctly detected lesions was significantly higher on Gd-EOB-DTPA-enhanced MRI compared with CT in the clinical evaluation [10.44%; 95% confidence interval (CI): 4.88, 16.0]. In the blinded reading there was a trend towards Gd-EOB-DTPA-enhanced MRI, not reaching statistical significance (2.14%; 95% CI: -4.32, 8.6). However, the highest rate of correctly detected lesions with a diameter below 1 cm was achieved by Gd-EOB-DTPA-enhanced MRI. Differential diagnosis was superior for Gd-EOB-DTPA-enhanced MRI (82.1%) versus CT (71.0%). A change in surgical therapy was documented in 19 of 131 patients (14.5%) post Gd-EOB-DTPA-enhanced MRI. Gd-EOB-DTPA-enhanced MRI was superior in the diagnosis and therapeutic management of focal liver lesions compared with CT. (orig.)

  7. Imaging diagnosis of solitary pulmonary nodules on an open low-field MRI system - comparison of two MR sequences with spiral CT

    Objective: To evaluate and compare two fast gradient-echo sequences (GRE) concerning the visualization of solitary pulmonary nodules with an open low-field MRI system in comparison to computed tomography. Materials and Methods: Fourteen patients with solitary pulmonary nodules detected by spiral CT ranging in size from 6 mm to 42 mm (mean 20 mm) underwent MRI on an open 0.2 T scanner using a spoiled 2D GRE (2D FLASH; TR/ TE/Flip = 100 ms/7.5 ms/30 ) and a totally refocused 2D steady-state GRE (True-FISP; TR/TE/FA = 7.3 ms/3.5 ms/80 ). The image quality concerning artifacts (by flow, breathing and susceptibility) and the morphologic characteristics of the nodules were scored and compared with CT by two independent radiologists. The diameters of the nodules measured by MRI were compared with CT measurements. The sequences were also evaluated with regard to the signal-to-noise ratio (SNR) of the lesion. Results: All lesions were detected with the 2D FLASH sequence. True