From the Departments of Medical Imaging (K.N., A.M., E.A.K.) and Neurology (B.M.C.), University of Arizona, Tucson, AZ; and the UCLA Stroke Investigators, University of California Los Angeles, Los Angeles, CA (D.S.L., J.P.V.).
Stroke. 2013 Nov;44(11):3090-6. doi: 10.1161/STROKEAHA.113.002377. Epub 2013 Aug 29.
This study compares the concordance between arterial spin labeling (ASL) and dynamic susceptibility contrast (DSC) for the identification of regional hypoperfusion and diffusion-perfusion mismatch tissue classification using a quantitative method.
The inclusion criteria for this retrospective study were as follows: patients with acute ischemic syndrome with symptom onset <24 hours and acquisition of both ASL and DSC MR perfusion. The volumes of infarction and hypoperfused lesions were calculated on ASL and DSC multi-parametric maps. Patients were classified into reperfused, matched, or mismatch groups using time to maximum >6 sec as the reference. In a subset of patients who were successfully recanalized, the identical analysis was performed and the infarction and hypoperfused lesion volumes were used for paired pre- and posttreatment comparisons.
Forty-one patients met our inclusion criteria. Twenty patients underwent successful endovascular revascularization (TICI>2a), resulting in a total of 61 ASL-DSC data pairs for comparison. The hypoperfusion volume on ASL-cerebral blood flow best approximated the DSC-time to peak volume (r=0.83) in pretreatment group and time to maximum (r=0.46) after recanalization. Both ASL-cerebral blood flow and DSC-TTP overestimated the hypoperfusion volume compared with time to maximum volume in pretreatment (F=27.41, P<0.0001) and recanalized patients (F=8.78, P<0.0001).
ASL-cerebral blood flow overestimates the DSC time to maximum hypoperfusion volume and mismatch classification in patients with acute ischemic syndrome. Continued overestimation of hypoperfused volume after recanalization suggests flow pattern and velocity changes in addition to arterial transit delay can affects the performance of ASL.
本研究通过定量方法比较动脉自旋标记（ASL）和动态对比增强磁共振（DSC）在识别局部低灌注和弥散-灌注不匹配组织分类方面的一致性。
本回顾性研究的纳入标准如下：症状发作<24 小时且同时采集 ASL 和 DSC 磁共振灌注成像的急性缺血综合征患者。在 ASL 和 DSC 多参数图上计算梗死和低灌注病变的体积。使用时间至峰值>6 秒作为参考，将患者分为再灌注、匹配或不匹配组。在一部分成功再通的患者中，进行了相同的分析，并使用治疗前后相同的梗死和低灌注病变体积进行配对比较。
41 名患者符合我们的纳入标准。20 名患者接受了成功的血管内再通治疗（TICI>2a），共获得 61 对 ASL-DSC 数据进行比较。预处理组中，ASL-脑血流与 DSC-峰值时间体积相关性最佳（r=0.83），再通后与时间至峰值相关性最佳（r=0.46）。预处理（F=27.41，P<0.0001）和再通患者（F=8.78，P<0.0001）中，ASL-脑血流和 DSC-TTP 均高估了低灌注体积。
在急性缺血综合征患者中，ASL-脑血流高估了 DSC 时间至峰值低灌注体积和不匹配分类。再通后低灌注体积的持续高估表明，除了动脉通过延迟外，血流模式和速度的变化也会影响 ASL 的性能。
