Abstract WP222: Basilar Artery Stenosis in Children With Moyamoya

Abstract

Introduction: Moyamoya is a progressive cerebrovascular disease characterized by stenosis of the cerebral arteries in the anterior circulation and less often the posterior circulation. To our knowledge, studies examining the prevalence of basilar artery stenosis do not exist outside of case reports. Methods: We retrospectively examined children with moyamoya followed at a single institution from November 2011 through August 2023. Children with moyamoya and basilar stenosis mentioned in their chart were initially included. A pediatric neurologist reviewed all records and neuroimaging to verify diagnosis of basilar artery stenosis. Results: Out of our cohort of 331 children with moyamoya, 24 (7.2%) children had basilar artery stenosis. In the group of 24 children with moyamoya and basilar artery stenosis 63% were females. The median age at moyamoya diagnosis was 4.8 years (interquartile range [IQR] 2.2,8.3). At time of diagnosis 16 children (67%) had basilar artery stenosis. The median time from diagnosis was 0 years (IQR 0, 1.3). At time of diagnosis all children had anterior circulation stenosis (internal carotid artery, middle cerebral artery and/or anterior cerebral artery), 13 (54%) had posterior cerebral artery stenosis and 6 (25%) had vertebral artery stenosis. Post-operative strokes following revascularization surgery occurred in 8 (33%) out of the 24 children. An associated disorder was found in 11 (46%) including ACTA2, PHACE syndrome, cranial radiation, trisomy 21, sickle cell disease, neurofibromatosis type 1 and morning glory disc. Conclusion: To our knowledge we present the first study to examine prevalence of basilar artery stenosis in a large single center cohort of children with moyamoya. In our cohort 7.2% of children with moyamoya had basilar artery stenosis. A large proportion of children with basilar artery stenosis developed stroke post-operatively. Genetic evaluation may be warranted in children with moyamoya and basilar artery stenosis given that 46% of the children had an associated disorder identified.