ASFNR Current State of Practice in Neuroimaging of Distal Medium Vessel Occlusion Stroke

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: 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.