Abstract TP102: Hypoperfusion Intensity Ratio Predicts Infarct Growth After Successful Thrombectomy For Distal Medium Vessel Occlusions

Abstract

Background and Purpose: We evaluated whether quantitative measurement of collaterals by the hypoperfusion-intensity-ratio (HIR) on baseline computed-tomography-perfusion (CTP) was correlated with infarct growth after successful endovascular recanalization of acute ischemic stroke (AIS) with primary distal, medium vessel occlusions (DMVO), as well as clinical outcome. Methods: We performed a retrospective analysis of consecutive AIS patients who underwent an initial CTP and were successfully recanalized by thrombectomy for DMVO. We evaluated the association of baseline HIR with infarct growth and clinical outcome. Results: Between January 2018 and January 2021, 40 patients suffering from an AIS with DMVO were successfully recanalized by MT (65% [26/40] female, median age 72 [65-83] years). Baseline HIR was strongly correlated with Infarct growth after successful recanalization (r=0.501, p=0.001). ROC analysis determined that a HIR<0.306 was an optimal threshold, it was associated with lower infarct growth compared to HIR≥0.306 (respectively 7.2 mL [IQR: 4.2-11.7] vs. 23.8 mL [IQR: 9.1-45.1], relative-risk of 0.38 [0.08-0.68], p = 0.015); as-well-as higher rates of good clinical outcome (75% [21/28] vs. 33% [4/12], p < 0.017, Odds ratio 6.0 [1.37-26.20]). Conclusion: Good collaterals on initial CTP assessed by an HIR<0.306 may be associated with less infarct growth and better clinical outcomes after MT recanalization for AIS with DMVO.