A review of acute ischemic stroke caused by distal, medium vessel occlusions

Acute ischemic stroke (AIS) due to distal, medium vessel occlusion (DMVO) is increasingly recognized as the next frontier for mechanical thrombectomy. Distal, medium vessel occlusions are typically defined as an occlusion in the following arteries: anterior cerebral artery, M2–M4 segments of the middle cerebral artery, posterior cerebral artery, posterior inferior cerebellar artery, anterior inferior cerebellar artery, and superior cerebellar artery. It is estimated that 25–40% of all AIS is due to DMVO. Because of the large burden of DMVO, the frequency of literature published regarding these occlusions has greatly increased in recent years. Furthermore, treatment modalities have been created specifically for DMVOs. Due to the rapidly evolving literature on this topic, remaining up to date on DMVO definitions, anatomy, management, imaging, and clinical course is difficult. In this review article, we synthesized existing literature regarding the aforementioned topics and discussed future directions.