Perfusion imaging to identify optimal large-core acute ischemic stroke candidates for mechanical thrombectomy


  • Mechanical thrombectomy improved clinical outcomes for patients with a larger ischemic penumbra (hypoperfusion to core ratio >1.2) in the setting of acute ischemic stroke with large vessel occlusion (LVO) and large ischemic core (>50 mL). Outcomes were also improved with mechanical thrombectomy in patients with ischemic core ≥70 mL plus a critical hypoperfusion to core volume ratio ≥1.8.

Why this matters

  • Traditionally, mechanical thrombectomy has not been recommended for patients with acute stroke with LVO and a large ischemic core (i.e., a large volume of irreversibly damaged brain tissue). These patients were underrepresented in pivotal trials due to the high likelihood of poor outcomes despite intervention.

  • Observational studies and subgroup analyses have suggested that penumbra size and persistence may influence functional benefits following mechanical thrombectomy in patients with large-core acute ischemic stroke.

  • Perfusion imaging may be used to calculate a critical hypoperfusion to core volume ratio that could help to stratify large-core ischemic stroke patients based on penumbra size. It is possible that patients with a large core, but substantial persistent penumbra may benefit from mechanical thrombectomy.