Abstract W P39: Internal Cerebral Vein Asymmetry on Follow-Up Brain CT after Intravenous Thrombolysis in Acute Anterior Circulation Ischemic Stroke is Associated With Poor Outcome

Abstract

Background and aim: Identifying early predictors of functional outcome after acute ischemic stroke (AIS) is important for planning rehabilitation strategies. Internal cerebral veins (ICV) drain deep parts of brain, run parallel to each other and consistently seen on CTA. Even minor asymmetry in their filling can be identified. We hypothesized that venous drainage would be impaired in patients with acute occlusion of ICA or MCA. Since systemic thrombolysis can alter the vascular findings, we evaluated the relationship between ICV asymmetry on follow-up CTA and functional outcome. Methods: Consecutive AIS patients treated with intravenous thrombolysis between 2007 and 2010 were included. ICV asymmetry was assessed by 2 independent blinded stroke neurologists/ neuroradiologists. Functional outcome was assessed by modified Rankin Scale (mRS) at 3-months, dichotomized as good (0-1) and poor (2-6). Data were analyzed for predictors of functional outcome. Results: Of 2238 patients with AIS, 226 (10.1%) anterior circulation AIS patients received intravenous thrombolysis. Median age 65yrs (range 19-92), 44% males and median National Institute of Health Stroke Scale (NIHSS) 16-points (range 4-32). Hypertension was the commonest risk factor in 173 (76.5%) while 78 (34.5%) had atrial fibrillation. ICV asymmetry on follow-up CTA was assessed in 103 (45.5%) patients. Admission NIHSS score (OR1.07;95%CI 1.079-1.201,p=0.046), change in NIHSS score during first 24 hours (OR 0.737; 95%CI 0.672-0.807,p<0.0001) and ICV asymmetry on follow-up CTA (OR 20.3;95%CI 4.67-52.07,p <0.0001) independently predicted poor outcome at 3-months. Conclusion: ICV asymmetry on follow-up CTA after intravenous thrombolysis is an early predictor of poor functional outcome.