Research Advances in Imaging Interpretation of DWI-FLAIR Mismatch in Acute Ischemic Stroke

doi:10.3969/j.issn.1673-5765.2025.09.016

Abstract

Abstract: In acute ischemic stroke (AIS), DWI-FLAIR mismatch refers to an imaging finding where the MRI DWI sequence shows hyperintensity in the acute infarct core, while the corresponding region on the FLAIR sequence displays isointensity. This finding reflects the spatial distribution discrepancy between the infarct core (irreversibly damaged area) and the ischemic penumbra (potentially salvageable area). Recent studies have demonstrated that assessment based on DWI-FLAIR mismatch can help identify AIS patients who still possess salvageable brain tissue. It provides an important imaging basis for determining the eligibility of patients with unknown onset time (such as wake-up stroke) for reperfusion therapy. In previous clinical studies, the interpretation of DWI-FLAIR mismatch primarily relied on visual assessment by physicians, thus leading to the issue of interpretive heterogeneity. With the development of technologies such as radiomics and deep learning, the interpretation of DWI-FLAIR mismatch is progressively advancing toward precision and intelligence. This article systematically reviews the recent advances in the imaging interpretation of DWI-FLAIR mismatch and prospectively discusses the optimization path of the emergency care system for AIS patients guided by precise imaging.

Key words: Acute ischemic stroke; Diffusion-weighted imaging-fluid attenuated inversion recovery mismatch; Imaging

摘要： 在急性缺血性卒中（acute ischemic stroke，AIS）中，DWI-FLAIR不匹配是指MRI DWI序列上显示有急性梗死病灶（呈现高信号），而对应的FLAIR序列显示该区域呈等信号的一种影像学表现。DWI-FLAIR不匹配反映了梗死核心（不可逆损伤区）与缺血半暗带（潜在可挽救区）在空间分布上的差异。近年来研究表明，基于DWI-FLAIR不匹配的缺血半暗带评估有助于筛选仍存在可挽救脑组织的AIS患者，为发病时间不明（如醒后卒中）的患者是否适宜接受再灌注治疗提供了重要的影像学依据。既往临床研究中，DWI-FLAIR不匹配的判读多依赖医师的视觉评估，因此存在判读异质性问题。随着影像组学与深度学习等技术的发展，DWI-FLAIR不匹配的判读正逐步向精准化与智能化方向迈进。本文系统综述了近年来DWI-FLAIR不匹配影像学判读的进展，并展望了基于精准影像学指导的AIS患者急救体系优化路径。

关键词: 急性缺血性卒中; 弥散加权成像-液体抑制反转恢复不匹配; 影像学

CLC Number:

LI Huan, YU Xiangming. Research Advances in Imaging Interpretation of DWI-FLAIR Mismatch in Acute Ischemic Stroke[J]. Chinese Journal of Stroke, 2025, 20(9): 1198-1202.

李欢, 于向明. 急性缺血性卒中DWI-FLAIR不匹配影像学判读研究进展[J]. 中国卒中杂志, 2025, 20(9): 1198-1202.

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