From the Department of Neurosciences, Experimental Neurology and Leuven Research Institute for Neuroscience and Disease (LIND), KU Leuven-University of Leuven, B-3000 Leuven, Belgium (A.W., R. Lemmens); VIB, Vesalius Research Center, Laboratory of Neurobiology, B-3000 Leuven, Belgium (A.W., R. Lemmens); Department of Neurology, University Hospitals Leuven, B-3000 Leuven, Belgium (A.W., R. Lemmens); Laboratory for Cognitive Neurology, KU Leuven, Herestraat 49, 3000 Leuven, Belgium (P.D.); Department of Clinical Sciences, Section of Neurology, Lund University, Sweden (B.N.); Guided Development GmbH, Heidelberg, Germany (R. Laage); Universitätsklinikum Hamburg-Eppendorf, Klinik und Poliklinik für Neurologie, Kopf-und Neurozentrum, Hamburg, Germany (G.T.); Stroke Center, Stanford University, Palo Alto, CA (G.W.A.); and Department of Neurology Austin Health, and Melbourne Brain Center, Florey Institute of Neuroscience and Mental Health, Heidelberg, Australia (V.T.).
Stroke. 2016 Oct;47(10):2559-64. doi: 10.1161/STROKEAHA.116.013903. Epub 2016 Sep 6.
Acute stroke patients with unknown time of symptom onset are ineligible for thrombolysis. The diffusion-weighted imaging and fluid-attenuated inversion recovery (FLAIR) mismatch is a reasonable predictor of stroke within 4.5 hours of symptom onset, and its clinical usefulness in selecting patients for thrombolysis is currently being investigated. The accuracy of the visual mismatch rating is moderate, and we hypothesized that the predictive value of stroke onset within 4.5 hours could be improved by including various clinical and imaging parameters.
In this study, 141 patients in whom magnetic resonance imaging was obtained within 9 hours after symptom onset were included. Relative FLAIR signal intensity was calculated in the region of nonreperfused core. Mean Tmax was calculated in the total region with Tmax >6 s. Mean relative FLAIR, mean Tmax, lesion volume with Tmax >6 s, age, site of arterial stenosis, core volume, and location of infarct were analyzed by logistic regression to predict stroke onset time before or after 4.5 hours.
Receiver-operating characteristic curve analysis revealed an area under the curve of 0.68 (95% confidence interval 0.59-0.78) for the visual diffusion-weighted imaging/FLAIR mismatch, thereby correctly classifying 69% of patients with an onset time before or after 4.5 hours. Age, relative FLAIR, and Tmax increased the accuracy significantly (P<0.01) to an area under the curve of 0.82 (95% confidence interval 0.74-0.89). This new predictive model correctly categorized 77% of patients according to stroke onset before versus after 4.5 hours.
In patients with unknown stroke onset, the accuracy of predicting time from symptom onset within 4.5 hours is improved by obtaining relative FLAIR and perfusion imaging.
对于症状发作时间不明的急性脑卒中患者，不适合进行溶栓治疗。弥散加权成像与液体衰减反转恢复（FLAIR）不匹配是症状发作 4.5 小时内发生脑卒中的合理预测指标，目前正在研究其在选择溶栓患者方面的临床应用价值。视觉不匹配评分的准确性为中等水平，我们假设通过纳入各种临床和影像学参数，可以提高 4.5 小时内脑卒中发作的预测准确性。
本研究纳入了 141 例在症状发作后 9 小时内进行磁共振成像检查的患者。在未再灌注核心区域计算相对 FLAIR 信号强度。在 Tmax>6 s 的总区域计算平均 Tmax。通过逻辑回归分析相对 FLAIR 平均值、Tmax 平均值、Tmax>6 s 的病变体积、年龄、动脉狭窄部位、核心体积和梗死部位，以预测 4.5 小时前或后脑卒中发作时间。
受试者工作特征曲线分析显示，视觉弥散加权成像/FLAIR 不匹配的曲线下面积为 0.68（95%置信区间 0.59-0.78），正确分类了 69%的 4.5 小时前或后发病的患者。年龄、相对 FLAIR 和 Tmax 显著提高了准确性（P<0.01），曲线下面积为 0.82（95%置信区间 0.74-0.89）。该新预测模型根据 4.5 小时前或后脑卒中发作正确分类了 77%的患者。
对于症状发作时间不明的脑卒中患者，通过获取相对 FLAIR 和灌注成像可以提高预测 4.5 小时内脑卒中发作时间的准确性。
