Abstract P354: SWAN-DWI Mismatch Predicts Clinical Outcome After Mechanical Thrombectomy

Objectives: Asymmetrically prominent veins on magnetic susceptibility sequences are thought to reflect the ischemic penumbra, by detecting high levels of desoxyheglobin. We investigated the relation between star-weighted angiography (SWAN)-diffusion weighted imaging (DWI) mismatch and clinical outcome after mechanical thrombectomy. Methods: We performed a retrospective study on patients who experienced anterior circulation stroke and for whom 1.5-Tesla MRI DWI and SWAN were performed upstream of mechanical thrombectomy. Mismatch was determined by using the Alberta Stroke Program Early CT Score (ASPECTS) on the diffusion-weighted and SWAN sequences. Three subgroups were defined in terms of mismatch level: high mismatch (HM), moderate mismatch (MM) and low mismatch (LM). Favorable outcome was defined as a modified Rankin score of 0-2 at three months. Multivariate logistic regression was used to examine associations between mismatch profiles and favorable outcomes. Results: The study included 108 patients who underwent mechanical thrombectomy. High mismatch was significantly associated with favorable clinical outcome (67% in the HM subgroup vs. 51% and 28% in the MM and LM subgroups respectively; odds ratio 1.25; 95 CI 1.02-1.56; p=0.037). No significant associations between SWAN-DWI mismatch and severe hemorrhagic complications or recanalization quality were brought to light by the present study. Conclusion: SWAN-DWI mismatch is a competent predictor of clinical outcome following mechanical thrombectomy.