Abstract 3998: Anterior Choroidal Artery Involvement Is Predictor Of Poor Neurological Outcomes In Distal Carotid Occlusions

Introduction Distal internal carotid (ICA) occlusions with ischemic stroke has been shown to have poor outcomes despite successful endovascular treatment related recanalization. Anterior choroidal artery (AchA) infarcts are commonly seen with distal ICA occlusion. We hypothesized that anterior choroidal artery territory involvement may be a key factor responsible for poor neurological outcomes in these patients and evaluated this hypothesis in two independent imaging databases of endovascular treated patients with distal ICA occlusion. Methods The computed tomography angiography (CTA) database of the Calgary stroke programme and Keimyung University MR databases were reviewed. All patients with acute ischemic stroke with distal ICA occlusions were identified. Patients with endovascular intervention with or without thrombolytic therapy were analyzed. CT or MRI done from day 1 - 7 after the procedure was evaluated for involvement of areas supplied by AchA. Patients from Keimyung University, Daegu South Korea had MR imaging with acute protocol before endovascular intervention. Patients with partial and complete involvement of anterior choroidal artery were categorized in the same group. MRS ≤2 at 3 months was used as good outcome. Recanalization was defined as TIMI 2-3 flow on angiography. Results Among 1454 patients from Calgary CTA database, 90 patients were identified to have distal ICA occlusions (Figure). Overall, involvement of anterior choroidal artery on followup imaging was a strong predictor of poor neurological outcomes (p=0.003, RR 4.3, 95% CI 1.57-11.75). Among 265 patients from Keimyung MR database, 55 patients were identified with distal ICA occlusions, of which 48 underwent endovascular treatment. Good Overall, involvement of anterior choroidal artery on baseline imaging was a strong predictor of poor neurological outcomes (p=0.003, RR 4.3, 95% CI 1.57-11.75). Overall, involvement of anterior choroidal artery on follow-up imaging was also a strong predictor of poor neurological outcomes (p=0.003, RR 4.3, 95% CI 1.57-11.75). Conclusion There is significant proportion of patients having AchA infarcts with distal ICA occlusion. Sparing of AchA territory is associated with good outcome whendistal ICA occlusions are successfully recanalized. Baseline AchA infarcts in a setting of distal ICA occlusion tend to have poor outcomes irrespective of whether recanalization is achieved.