椎动脉颅外段血流动力学参数对颅内段闭塞性病变的准确性研究

Accuracy study of hemodynamic parameters of extracranial segment of vertebral artery for occlusive lesions in intracranial segment

目的通过超声检测椎动脉颅外段血流动力学参数,评估椎动脉颅内段闭塞性病变的准确性。方法回顾性连续纳入2015年1月至2017年12月于宣武医院神经内科、神经外科因后循环缺血性卒中或短暂性脑缺血发作(TIA)而住院,行常规头颈部血管超声检查,经CT血管成像(CTA)和(或) DSA检查确诊为单侧椎动脉颅内段狭窄或闭塞患者共275例,记录椎动脉颅外段收缩期峰值流速(PSV)、舒张期末流速(EDV)、阻力指数(RI),以DSA检查结果为参照计算PSV、EDV、RI值的受试者工作特征(ROC)曲线下面积(AUC),比较上述各血流动力学参数在不同取值下评估椎动脉颅内段闭塞性病变的敏感度、特异度和准确性。结果 (1)经ROC曲线比较,发现评估椎动脉颅内段发出小脑后下动脉(PICA)之前闭塞,EDV、RI值具有较大的AUC(分别为0. 985和0. 977);评估发出PICA之后闭塞,EDV和PSV具有较大的AUC (分别为0. 959和0. 922); PSV、EDV、RI评估椎动脉颅内段重度狭窄的AUC相对较低(分别为0. 875、0. 894、0. 826)。(2)当EDV≤0 cm/s或RI≥1. 00时,诊断椎动脉颅内段发出PICA之前闭塞的准确性均为97. 8%,特异度和敏感度均分别为98. 7%、91. 9%。当EDV≤10 cm/s时,诊断椎动脉发出PICA之后闭塞的准确性为89. 1%,敏感度91. 2%,特异度87. 9%; PSV≤39 cm/s、RI≥0. 76时,诊断准确性分别为86. 2%、84. 7%。椎动脉颅外段血流动力学参数EDV、PSV、RI评估颅内段重度狭窄的准确性均未达到85. 0%。结论椎动脉颅外段血流动力学参数能够准确诊断椎动脉颅内段闭塞,并且能够区分闭塞部位,但是对重度狭窄的诊断准确性相对较低。

Objective To evaluate the accuracy of vertebral artery occlusive lesions in intracranial segment by measuring the hemodynamic parameters of vertebral artery in extracranial segment with ultrasound. Methods From January 2015 to December 2017,consecutive inpatients with posterior circulation ischemic stroke or transient ischemic attack(TIA) at the Departments of Neurology and Neurosurgery,Xuanwu Hospital,Capital Medical University were enrolled retrospectively. They were examined with head and neck vascular ultrasound. A total of 275 patients were diagnosed as unilateral intracranial vertebral artery stenosis or occlusion after CT angiography(CTA) and/or digital subtraction angiography(DSA) examinations. The peak systolic velocity(PSV),end diastolic velocity(EDV),and resistance index(RI) of the extracranial segment of the vertebral artery were recorded. DSA findings were used as reference,the area under the receiver operating characteristic(ROC) curves(AUC) of the PSV,EDV,and RI values were calculated. The sensitivity,specificity,and accuracy of each of the above hemodynamic parameter at different values were compared. Results(1) By comparing ROC curves,it was found that EDV and RI values had higher AUC(0. 985 and 0. 977 respectively) before evaluating the occlusion of posterior inferior cerebellar artery(PICA) in the intracranial segment of vertebral artery. EDV and PSV had larger AUC(0. 959 and0. 922 respectively) after evaluating the occlusion of PICA. AUCs of PSV,EDV and RI in evaluating severe stenosis in intracranial segment of vertebral artery were relatively lower(0. 875,0. 894 and 0. 826,respectively).(2) When EDV ≤0 cm/s or RI ≥1. 00,the accuracy of occlusion before the diagnosis of PICA in the intracranial segment of the vertebral artery was 97. 8%,and the specificity and sensitivity were98. 7% and 91. 9% respectively. When EDV ≤10 cm/s,the accuracy of occlusion after diagnosis of vertebral artery PICA was 89. 1%,the sensitivity was 91. 2%,specificity was 87. 9%; PSV ≤39 cm/s,RI ≥0. 76,the diagnostic accuracy were 86. 2 % and 84. 7 % respectively. The accuracy of cerebral hemodynamic parameters EDV,PSV,and RI in the evaluation of severe intracranial stenosis was less than85. 0 %. Conclusions The hemodynamic parameters of the extracranial segment of the vertebral artery can accurately diagnose the occlusion of the vertebral artery,and distinguish the occlusion sites. However,the diagnostic accuracy for severe stenosis is relatively lower.