256iCT血管成像在下肢动脉支架植入术后的应用价值

The Value of 256iCT Angiography in Lower Extremity Artery Stent

目的探讨256iCT血管成像在下肢动脉支架植入术后支架内再狭窄的应用价值。方法对36例有临床症状的下肢动脉支架植入术后患者行256iCT下肢动脉增强扫描,将薄层轴位原始图像传入EBW工作站,运用曲面重组(curve plannar reconstruction,CPR)、多平面重组(multiplannar reconstruction,MPR)、最大密度投影(maximum intensity projection,MIP)、容积再现(volume rendering,VR)等后处理方法进行血管重组。所有患者在行CT扫描后1周内行数字减影血管造影(digital subtraction angiography,DSA)检查。以DSA结果为金标准,计算256iCT对支架内再狭窄的敏感性、特异性、阳性预测值、阴性预测值及准确性。结果 36例患者共放置支架72枚,其中58枚(80.6%)支架显影良好可以评价。在可评价支架中,以DSA为诊断标准,血管重组图像结合原始轴位图像,256iCT血管成像诊断下肢动脉支架再狭窄的敏感性、特异性、阳性预测值、阴性预测值及准确性分别为100%(27/27)、96.8%(30/31)、96.4%(27/28)、100%(30/30)、98.3%(57/58)。结论 256iCT下肢血管成像评价下肢动脉支架术后再狭窄的敏感性和准确性较高,可以作为下肢动脉支架术后怀疑支架内再狭窄患者的重要检查手段。

Objective To assess the clinical value of 256iCT angiography in the diagnosis of lower extremity artery in-stent restenosis（ISR）.Methods A total of 36 patients with symptomatic lower extremity arterial occlusive disease after lower extremity artery stenting（72 stented lesions） underwent 256iCT angiography.Original axial images were transferred to EBW workstation and reconstruction images（CPR、MPR、MIP、VR） were performed.36 patients underwent digital subtraction angiography（DSA） in the following week after CT angiography.The sensitivity,specificity,positive predictive value,negative predictive values and accuracy of 256iCTA for diagnosis of ISR were analyzed,with DSA as the reference standard.Results Of 72 stents,58（79.2%） were determined to be assessable on CTA.Overall,DSA images as the reference standard,arterial reconstruction images combined with the original axial images,the sensitivity,specificity,positive predictive value,negative predictive value and accuracy of 256iCTA were 100%（27/27）、96.8%（30/31）、96.4%（27/28）、100%（30/30）、98.3%（57/58） in detecting the in-stents restenosis.Conclusion 256iCT angiography have high sensitivity and accuracy for the diagnosis of ISR,therefore,it can be used in clinical practice as a test for patients with suspected ISR after lower extremity stent implantation.