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1.

Purpose

Our aim was to evaluate the accuracy, sensitivity and specificity of 64-slice multidetector computed tomography (MDCT) in the assessment of occlusions and stenoses of arterial and venous bypass grafts and disease progression in the native vessels distal to the graft, and to compare the results with those of conventional coronary angiography.

Materials and methods

We enrolled 78 individuals (45 men, 33 women; mean age 59) and evaluated 213 bypass grafts using a 64-slice MDCT scanner. All patients underwent conventional coronary angiography with a mean time interval between the two examinations of 2 days.

Results

One patient was excluded due to arrhythmia during the examination. The 212 bypass grafts in the remaining 77 patients (98.7%) consisted of 115 (54%) venous grafts and 97 (46%) arterial grafts. In the 115 venous grafts, MDCT showed a sensitivity, specificity and accuracy of 100% in evaluating occluded grafts and a sensitivity of 94.4%, specificity of 98.4% and accuracy of 96.9% in evaluating significant stenoses. In evaluating occluded arterial grafts, sensitivity was 83.3%, specificity 100% and accuracy 98.9%, whereas in evaluating stenoses of arterial grafts, sensitivity was 100%, specificity 97.7% and accuracy 98%.

Conclusions

Sensitivity, specificity and accuracy in evaluating native coronary vessels distal to the graft allow for a complete assessment of the surgical and native circulation. The examination appears therefore to be exhaustive in ruling out or confirming the presence of diseased vessels in the postoperative follow-up.  相似文献   

2.
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.  相似文献   

3.
目的评价320排动态容积CT(320-slice dynamic volume CT,320-DVCT)动脉造影诊断冠状动脉支架内部再狭窄的准确性。 方法208例怀疑发生支架内再狭窄的冠状动脉支架植入患者,进行320-DVCT动脉造影检查,之后2~7 d内行冠状动脉造影检查。 结果320-DVCT动脉造影可获得较好的图像质量,可用于诊断冠状动脉支架内再狭窄。对于直径≥3.0 mm的支架,其图像优级率和成功率明显高于直径<3.0 mm的支架。320-DVCT诊断冠状动脉支架内再狭窄的敏感性91.30%,特异性95.21%,阳性预测值86.3%,阴性预测值97.07%,准确率94.24%;诊断左前降支支架内再狭窄的敏感性89.29%,特异性96.77%,阳性预测值89.29%,阴性预测值96.77%,准确率95.04%;诊断左回旋支支架内再狭窄的敏感性88.89%,特异性92.73%,阳性预测值80.00%,阴性预测值96.23%,准确率91.78%;诊断右冠状动脉支架内再狭窄的敏感性88.00%,特异性94.92%,阳性预测值88.00%,阴性预测值94.92%,准确率92.86%。 结论320-DVCT动脉造影是目前较新的一种安全无创、有效诊断冠状动脉支架内再狭窄的检查方法。  相似文献   

4.
Multislice CT coronary angiography (CT-CA) has emerged as a potential imaging method for coronary artery disease. This study aimed to ascertain the accuracy of 16-slice CT in the diagnosis of significant coronary stenosis (>or=50% reduction of lumen diameter). This mixed retrospective/prospective observational study compared 95 paired 16-slice CT-CA and fluoroscopic coronary angiography (FCA) sets. A cardiologist and a radiologist blinded to the FCA findings evaluated CT-CA images independently by visual estimation. Disagreement between these reporters was arbitrated by a third CT reporter (a cardiologist). A separate cardiologist blinded to CT-CA findings assessed FCA by visual estimation. Of 1,161 coronary segments assessable on FCA, 1,103 segments (95%) were assessable on CT-CA. The CT-CA correctly diagnosed 147/180 segments with significant stenoses (sensitivity = 82%) and correctly identified 874/923 coronary segments without significant stenoses (specificity = 95%). The positive and negative predictive values of CT-CA in the diagnosis of coronary segment with significant stenosis were 75 and 96%, respectively. On patient-based analysis, CT-CA correctly identified all 68 studies with at least one vessel with significant stenosis (sensitivity = 100%; specificity = 83%). The positive and negative predictive values of CT-CA in identifying patients with significant coronary stenosis were 94 and 100%, respectively. The 16-slice CT-CA showed moderately good sensitivity but very high specificity and negative predictive value in the diagnosis of significant coronary stenosis. The CT-CA would appear to be a useful 'rule-out' test for patients with low-risk profile for ischaemic heart disease.  相似文献   

5.
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 diameter.  相似文献   

6.
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° and 45° 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.  相似文献   

7.

Purpose

The aim of this study was to perform a meta-analysis of the diagnostic accuracy of 64-slice CT angiography for the detection of coronary in-stent restenosis in patients treated with coronary stents when compared to conventional coronary angiography.

Materials and methods

A search of PUBMED/MEDLINE, ProQuest and Cochrane library databases for English literature was performed. Only studies comparing 64-slice CT angiography with conventional coronary angiography for the detection of coronary in-stent restenosis (more than 50% stenosis) were included for analysis. Sensitivity and specificity estimates pooled across studies were tested using a fixed effects model.

Results

Fourteen studies met selection criteria for inclusion in the analysis. The mean value of assessable stents was 89%. Prevalence of in-stent restenosis following coronary stenting was 20% among these studies. Pooled estimates of the sensitivity and specificity of overall 64-slice CT angiography for the detection of coronary in-stent restenosis was 90% (95% CI: 86%, 94%) and 91% (95% CI: 90%, 93%), respectively, based on the evaluation of assessable stents. Diagnostic value of 64-slice CT angiography was found to decrease significantly when the analysis was performed with inclusion of nonassessable segments in five studies, with pooled sensitivity and specificity being 79% (95% CI: 68%, 88%) and 81% (95% CI: 77%, 84%). Stent diameter is the main factor affecting the diagnostic value of 64-slice CT angiography.

Conclusion

Our results showed that 64-slice CT angiography has high diagnostic value (both sensitivity and specificity) for detection of coronary in-stent restenosis based on assessable segments when compared to conventional coronary angiography.  相似文献   

8.
PURPOSE: Our aim was to evaluate the diagnostic accuracy of 64-slice computed tomography coronary angiography (MSCT-CA) for detecting significant stenosis (>or=50% lumen reduction) in a population of patients at low to intermediate risk. MATERIALS AND METHODS: We studied 72 patients (38 men, 34 women, mean age 53.9+/-8.0 years) with atypical or typical chest pain and stratified in the low-to intermediate risk category. MSCT-CA (Sensation 64 Cardiac, Siemens, Germany) was performed after IV administration of 100 ml of iodinated contrast material (Iomeprol 400 mgI/ml, Bracco, Italy). Two observers, blinded to the results of conventional coronary angiography (CAG), assessed the MSCT-CA scans in consensus. Diagnostic accuracy for detecting significant stenosis was calculated. RESULTS: CAG demonstrated the absence of significant disease in 70.1% of patients (51/72). No patient was excluded from MSCT-CA. There were 37 significant lesions on 1,098 available coronary segments. Sensitivity, specificity and positive and negative predictive value of MSCT-CA for detecting significant coronary artery on a per-segment basis were 100%, 98.6%, 71.2% and 100%, respectively. All patients with at least one significant lesion were correctly identified by MSCT-CA. MSCT-CA scored 15 false positives on a per-segment base, which affected only marginally the per-patient performance (only one false positive). CONCLUSIONS: We concluded that 64-slice CT-CA is a diagnostic modality with high sensitivity and negative predictive value in patients at low to intermediate risk.  相似文献   

9.
目的评价64层螺旋CT冠状动脉血管成像(CTCA)对冠状动脉变异的诊断价值及临床评价。方法回顾性分析3529例临床疑为心肌缺血患者及常规体查者冠状动脉CTA影像检查结果并对发现的变异冠状动脉进行分类。结果3529例冠状动脉CTA受检者中,共检出冠状动脉变异42例(1.19%,42/3529),MIP、VRT、CPR重建图像均明确显示其开口及走行;其中右冠状动脉起自主动脉左冠状窦者9例,左冠状动脉起自主动脉右冠状窦者2例,左回旋支异位开口于右冠窦1例,冠状动脉高位开口于升主动脉壁者6例.并行左主干3例(前降支、旋支分别开口于左冠窦),左主干开口于肺动脉伴右冠状动脉瘤1例,左旋支-冠状静脉瘘者2例,副冠状动脉9例,右冠状动脉-左心室瘘合并右冠状动脉瘤l例。冠状动脉发育不良8例。结论冠状动脉CTA能准确显示各种类型冠状动脉变异,可作为无创性诊断冠状动脉变异的首选方法。  相似文献   

10.
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.  相似文献   

11.
近年来随着我国社会经济的发展,人们的生活水平的不断提高以及生活习惯及饮食习惯的改变,冠状动脉性疾病的发病率呈现不断上升的趋势,且发病患者的年龄也越来越趋于年轻化。冠状动脉疾病临床上主要为冠状动脉硬化,此外还包括冠状动脉畸形、冠状动脉痉挛等。目前对冠状动脉疾病的诊断主要依赖于影像学检查[1],为了探讨64层螺旋 CT 冠状动脉CTA 在冠状动脉疾病的诊断中的应用价值,特作以下研究。  相似文献   

12.
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.  相似文献   

13.
冠状动脉钙化对64层螺旋CT诊断冠状动脉狭窄的影响   总被引:10,自引:0,他引:10  
目的探讨64层螺旋CT(MSCT)诊断伴钙化斑块的冠状动脉狭窄的正确性。方法60例患者同期行64层MSCT冠状动脉扫描和常规冠状动脉造影(CCA)。用MSCT的平扫图像行钙化积分测定,以CCA结果为金标准,得出64层MSCT诊断有意义病变(冠状动脉狭窄率≥50%)的正确性,并分析钙化对诊断正确性的影响。结果分析797个可以诊断的冠状动脉节段,得出MSCT诊断的敏感性为96%(174/182),特异性为98%(601/615),阳性预测值为93%(174/188),阴性预测值为99%(601/609)。对于钙化积分≥100分(Agatston评分)的冠状动脉节段,MSCT诊断的特异性为63%(12/19),阳性预测值为81%(30/37)。结论对于冠状动脉无钙化或者轻度钙化者,64层MSCT可作为诊断冠心病的可靠手段应用于临床。对于严重钙化者,其诊断的特异性和阳性预测值明显下降。  相似文献   

14.

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.  相似文献   

15.
目的:探讨64层螺旋CT冠状动脉成像的临床应用价值。方法:对120例临床拟诊为冠心病或已确诊的冠心病患者,行64层螺旋CT血管成像,对所有原始数据采用容积再现(VR)、最大密度投影(MIP)、曲面重建(CPR)进行图像后处理,显示冠状动脉主干及主要分支。结果:心率小于70次/min且平稳时冠状动脉成像质量最佳,可较准确显示冠状动脉通畅情况、冠状动脉斑块、狭窄程度及管壁病变。对于搭桥血管及支架植入是否通畅及是否再狭窄显示良好。结论:64层螺旋CT冠状动脉成像无创、快速,对冠状动脉病变的筛选,桥血管及内支架术后疗效随访等有很大的应用价值。  相似文献   

16.
冠状动脉粥样硬化性心脏病(简称冠心病)是一种常见病、多发病。常规冠脉造影是一种有创检查,费用高,很多患者难以接受。多层螺旋CT冠状动脉成像(冠脉CAG)技术,尤其是64层螺旋CT采用多排探测器及锥形X线束,可实现亚秒级扫描,时间分辨率和空间分辨率明显提高,且真正实现了各向同性,  相似文献   

17.
张滨  李英  李海波 《医学影像学杂志》2007,17(12):1294-1296
目的:总结大样本病例64排螺旋CT冠状动脉成像中发现的冠状动脉变异类型及数量,为临床诊治提供依据,积累冠状动脉活体形态学资料,提高对冠状动脉变异的认识。方法:对694例受检者进行心脏冠脉成像检查,并对其图像进行回顾性分析。结果:694例受检者中,44例发现4种不同类型冠状动脉变异,占总数6.34%。其中副冠状动脉33例,RCA起源于左窦2例,LCX起源于右窦7例,左冠状动脉开口异常2例。结论:64排螺旋CT冠状动脉成像可以无创观察冠状动脉解剖及变异,为临床治疗提供依据。对冠状动脉细小分支的显示及对冠状动脉变异的认识有待提高。  相似文献   

18.
目的探讨64排容积CT尿路成像在输尿管结石中的诊断价值。 方法分析200例输尿管结石的患者,其被临床或者手术判定为输尿管结石,所有入选的患者行64排容积CT尿路成像,并采用不同图像后处理:多平面重组法、曲面重组、最大密度投影、容积再现、表面成像。 结果在入选的200例患者中,结石最小的直径为1.5mm,结石位于输尿管上段的有70例,位于下段的有83例,位于中段的有35例,位于输尿管上中下段的有12例。同时还发现合并输尿管畸形的患者。其中,合并肾囊肿的有100例,输尿管囊肿的有5例,膀胱憩室的4例,合并肾结石的有30例,合并膀胱结石的有10例,合并输尿管及肾积脓的2例,肾盂及输尿管畸形的有20例。 结论64排容积CT对于输尿管结石的定位、大小、形态、数量及其周围情况的诊断具有重要的价值,同时可显示泌尿系统是否合并畸形及肾结石、膀胱结石。  相似文献   

19.
目的 探讨64层螺旋CT血管成像技术对主动脉病变的诊断及临床应用价值.方法 32例主动脉病变患者行64层螺旋CT扫描,并对原始数据采用多平面重组(MPR)、曲面成像(CPR)、最大密度投影(MIP)、容积再现(VR)、高级血管分析(AVA)处理.32例主动脉病变均经临床、手术证实.结果 32例主动脉病变中,主动脉夹层16例、假性动脉瘤7例、真性动脉瘤4例、主动脉弓缩窄3例、主动脉离断2例.MPR对内膜破口、附壁血栓显示较佳.内膜片及初始破口显示率为81%(13/16),7例假性动脉瘤周围血栓,显示率100%(7/7);CPR简单、直观显示病变全程,显示率100%(32/32);MIP对钙化及管径精确测量颇有价值,显示率84%(27/32);VR能明确病变的范围和周围血管关系,显示率100%(32/32);AVA对测量血管管径、血管横截面积具有意义,显示率44%(14/32).结论 64层螺旋CT血管成像技术对主动脉病变的诊断具有重要意义.  相似文献   

20.

Background

We sought to evaluate the diagnostic accuracy of 64-slice multi-detector row computed tomography (MDCT) compared with invasive coronary angiography for in-stent restenosis (ISR) detection.

Methods

MEDLINE, Cochrane library, and BioMed Central database searches were performed until April 2009 for original articles. Inclusion criteria were (1) 64-MDCT was used as a diagnostic test for ISR, with >50% diameter stenosis selected as the cut-off criterion for significant ISR, using invasive coronary angiography and quantitative coronary angiography as the standard of reference; (2) absolute numbers of true positive, false positive, true negative, and false negative results could be derived. Standard meta-analytic methods were applied.

Results

Nine studies with a total of 598 patients with 978 stents included were considered eligible. On average, 9% of stents were unassessable (range 0-42%). Accuracy tests with 95% confidence intervals (CIs) comparing 64-MDCT vs invasive coronary angiography showed that pooled sensitivity, specificity, positive and negative likelihood ratio (random effect model) values were: 86% (95% CI 80-91%), 93% (95% CI 91-95%), 12.32 (95% CI 7.26-20.92), 0.18 (95% CI 0.12-0.28) for binary ISR detection. The symmetric area under the curve value was 0.94, indicating good agreement between 64-MDCT and invasive coronary angiography.

Conclusions

64-MDCT has a good diagnostic accuracy for ISR detection with a particularly high negative predictive value. However, still a relatively large proportion of stents remains uninterpretable. Accordingly, only in selected patients, 64-MDCT may serve as a potential alternative noninvasive method to rule out ISR.  相似文献   

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