64排螺旋CT血管成像在诊治椎动脉起始部狭窄中的价值

Diagnosis of stenosis at the origin of the vertebral artery with 64-slice spiral digital subtraction CT angiography and its values for predicting the result of stenting

目的评价64排螺旋CT减影血管成像(DSCTA)诊断椎动脉起始部狭窄及在支架成形术术前评估的应用价值。方法 78例患者全部行DSCTA和IDSA检查。应用北美颈动脉内膜切除试验狭窄分级法,在显示狭窄的最佳角度上测定椎动脉最狭窄处的直径(N)与椎动脉起始部远端的正常血管直径(D),计算狭窄率。IDSA检查结果和DSCTA检查结果进行等级相关分析。以DSA检查结果为金标准,以狭窄率30%、50%及70%为界限,评估DSCTA检查椎动脉起始部狭窄的诊断价值。结果①等级相关分析中,DSA检查结果和DSCTA检查结果的等级相关系数为0.960,P<0.01。②以DSA检查结果为金标准,以狭窄率30%、50%及70%为界限,在此3个界限范围内,DSCTA检查的敏感度、特异度、阳性预测值、阴性预测值、准确度均>90%,假阳性率<10%、假阴性率<2%、阳性似然比>10,Youden指数均接近或超过0.9。CDSCTA评估符合椎动脉起始部支架置入术的患者共59例,术中以DSA检查进一步评估,最终行支架置入术55例,DSCTA评估的符合率为93%。④DSCTA可清晰地显示椎动脉起始部狭窄的位置、形态、斑块的性质,还可去除周围干扰,从多角度观察椎动脉起始部的狭窄。结论 DSCTA是诊断椎动脉起始部狭窄的可靠方法 ,并可作为介入治疗术前评估的主要手段。

Objective To evaluate the diagnosis of stenosis at the origin of the vertebral artery with 64-slice spiral digital subtraction CT angiography （DSCTA） and its value for predicting the resuh of stenting. Methods All the 78 patients were examined with DSCTA and DSA. The diameter at the most stenotic site of vertebral artery （N） and the diameter of normal blood vessel distal to the origin of the vertebral artery （D） were measured using the grading method of the North American Symptomatic Carotid Endarterectomy Trial （NASCET）. The stenosis rate was calculated. Spearman＇s rank correlation analysis was performed for the examination results of DSCTA and DSA. Take the examination result of DSA as the gold standard. 30% , 50% , and 70% stenosis were used as the boundary values, the diagnostic value of DSCTA for detecting the stenosis of the vertcbral artery origin was evaluated. Results ①In rank correlation analysis, the Spearman＇s rank correlation coefficients of the examination results of DSA and DSCTA were 0. 960 （P 〈 0.01 ）. ②Taking the DSA result as the gold standard, the stenosis rates of 30%, 50% and 70% were used as the boundary values, In the content of the above three limits, the sensitivity, specificity, positive predicting value, negative predictive value, and accuracy of the DSCTA examinations were more than 90% , the false positive rate was less than 10% , the false negative rates was less than 2% , the positive likelihood ratio was more than 10, and the Youden index was close to or more than 0.9. ③A total of 59 patients assessed with DSCTA met the criteria of stenting at the origin of vertebral artery. After further intraoperative assessment with DSA, finally the stentings were performed in 55 patients. The coincidence rate of the DSCTA assessment was 93%. ④DSCTA could clearly show the position, shape, and plaque feature at the origin of vertebral artery, also could exclude the surrounding interference, and observe the stenosis at origin of vertebral artery from various angles. Conclusion DSCTA is a reliable method for the diagnosis of the stenosis at the origin of vertebral artery, and it may serve a means for evaluation the result of interventional treatment preoperativly.