Background and Purpose—This study aimed to derive and validate an optimal collateral measurement on computed tomographic perfusion imaging for patients with acute ischemic stroke.Methods—In step 1 analysis of 22 patients, the parasagittal region of the ischemic hemisphere was divided into 6 pial arterial zones to derive the optimal collateral threshold by receiver operating characteristic analysis. The collateral threshold was then used to define the collateral index in step 2. In step 2 analysis of 156 patients, the computed tomographic perfusion collateral index was compared with collateral scores on dynamic computed tomographic angiography in predicting good clinical outcome by simple regression.Results—The optimal collateral threshold was delay time >6 s (sensitivity, 88%; specificity, 92%). The computed tomographic perfusion collateral index, defined by the ratio of delay time >6 s/delay time >2 s volume, showed a significant correlation with dynamic computed tomographic angiography collateral scores (correlation coefficient, 0.62; P<0.001), with an optimal cut point of 31.8% in predicting good collateral status (sensitivity of 83% and specificity of 86%). When predicting good clinical outcome, the delay time collateral index showed a similar predictive power to dynamic computed tomographic angiography collaterals (area under the curve, 0.78 [0.67–0.83] and 0.77 [0.69–0.84], respectively; P<0.001).Conclusions—Computed tomographic perfusion can accurately quantify collateral flow after acute ischemic stroke.

中文翻译：

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灌注计算机断层扫描可准确量化急性缺血性中风后的侧支血流。

背景与目的-本研究旨在推导并验证急性缺血性卒中患者在计算机断层扫描灌注成像中的最佳并行测量。方法-在22例患者的第1步分析中，将缺血半球的矢状旁矢状区域分为6股动脉通过接收器工作特性分析得出最佳抵押品阈值。然后，在第2步中使用并行阈值定义并行指数。在对156例患者进行的第2步分析中，将计算的X线断层造影并行指数与动态X线断层血管造影上的并行分数进行比较，以通过简单的回归预测良好的临床结果。最佳并行阈值是延迟时间> 6 s（敏感性为88％；特异性为92％）。P <0.001），在预测良好的侧支状态时最佳切点为31.8％（敏感性为83％，特异性为86％）。当预测良好的临床结果时，延迟时间侧支指数显示出与动态计算机断层血管造影侧支相似的预测能力（曲线下面积分别为0.78 [0.67-0.83]和0.77 [0.69-0.84]；P <0.001）。 -计算机断层扫描灌注可以准确量化急性缺血性中风后的侧支血流。