远端中等血管闭塞卒中的神经影像实践现状：ASFNR指南解读
远端中等血管闭塞约占急性缺血性卒中的25%-40%，因血管管径细、走行迂曲及标准CTA敏感度低而诊断困难。近期多项多中心随机对照试验显示机械取栓与最佳药物治疗相比结果异质，且取栓组症状性颅内出血率更高。本文总结当前证据，为放射科医生提供DMVO检测、工作流程标准化、分诊及影像预后评估的实践指南。
要点
- 优化CTA（包括多时相）可提高DMVO诊断信心，应作为首选筛查方法。
- CT灌注 territorial Tmax 和MRI DWI/SWI有助于提高诊断置信度。
- rCBV指数和低灌注强度比等灌注参数对侧支状态和预后有预测价值。
关键影像表现/征象
- 优化CTA（包括多时相）可提高DMVO诊断置信度。
- CT灌注 territorial Tmax 和MRI DWI/SWI可提高DMVO诊断置信度。
- rCBV指数和低灌注强度比等灌注参数可反映侧支状态并具有预后价值。
临床应用与阅片要点
- 采用优化CTA（包括多时相）作为DMVO检测的首选影像方法。
- 结合CT灌注 territorial Tmax 或MRI DWI/SWI提高诊断置信度。
- 利用rCBV指数和低灌注强度比等灌注参数评估侧支状态和预后。
- 结构化报告重要阳性和阴性影像发现，以指导神经科分诊。
以上解读依据论文摘要（全文未开放获取或许可不允许翻译转载）。
英文原文（摘要）· 点击展开
BACKGROUND: Distal medium vessel occlusions (DMVO) constitute approximately 25%-40% of acute ischemic stroke. These potentially disabling strokes remain diagnostically challenging due to vessel caliber, tortuosity, and low sensitivity of standard CT angiography.
RECENT DEVELOPMENTS: Multiple recent multicenter randomized controlled trials (DISTAL, ESCAPE-MeVO, DISCOUNT, ORIENTAL-MeVO and DISTALS) showed overall heterogenous results of mechanical thrombectomy (MT) over best medical treatment to treat DMVO, with higher symptomatic intracranial hemorrhage rates in the MT arm.
PURPOSE: Summarize current evidence and provide a "state of practice" guide for radiologists on DMVO detection, workflow standardization, triage, and imaging-based prognostication.
KEY POINTS: Optimized CTA (including multiphase), CT Perfusion (territorial Tmax), and MRI DWI/SWI improve diagnostic confidence for DMVO. Certain perfusion parameters indicative of collateral status, for instance, rCBV index and hypoperfusion intensity ratio, have prognostic value. Structured reporting of important positive and negative radiologic findings can guide neurologic triage despite neutral trials.
CONCLUSION: Radiologists play a central role in DMVO diagnosis and prognostication. Standardized imaging workflows are essential in the post-trial landscape.
引用
- Sriwastwa A, Allen JW, Jain R, et al. ASFNR Current State of Practice in Neuroimaging of Distal Medium Vessel Occlusion Stroke. AJNR Am J Neuroradiol. 2026. PMID: 42134995. doi:10.3174/ajnr.A9411
供执业医师工作参考，不替代临床判断；数值与分级以指南原文为准。