Clinical Presentation and Stroke Incidence Differ by Moyamoya Etiology

Abstract

Introduction: Moyamoya arteriopathy, which can be idiopathic or associated with sickle cell disease, neurofibromatosis, Down syndrome, or cranial radiation therapy, is a progressive cerebral arteriopathy associated with high rates of incident and recurrent stroke. Little is known about how these subgroups differ with respect to clinical presentation, radiographic findings, stroke risk, and functional outcomes. Methods: Using ICD codes, we identified children ages 28 days to 18 years treated for moyamoya arteriopathy at our tertiary care center between 2003 and 2019. Demographic, clinical, and radiographic data were extracted from the medical record. The Pediatric Stroke Recurrence and Recovery Questionnaire was administered to consenting participants. Results: Sixty-nine patients met inclusion criteria (33 idiopathic, 18 sickle cell disease, 11 neurofibromatosis, 6 Down syndrome, 1 cranial radiation therapy). Median follow-up time was 7.7 years; 24 patients had at least 5 years of follow-up data. Frequency of stroke at presentation differed by subgroup ( P < .001). Of patients with at least 2 years of follow-up, 33 (55%) experienced stroke. The proportion of patients experiencing stroke differed by subgroup (50% of idiopathic cases, 72% of sickle cell disease, 11% of neurofibromatosis, and 100% of Down syndrome, P = .003). The frequency of bilateral versus unilateral disease ( P = .001) and stroke-free survival following presentation ( P = .01) also differed by subgroup. Conclusions: In this single-center cohort, moyamoya subgroups differed with respect to clinical and radiographic characteristics, with neurofibromatosis-associated moyamoya syndrome having a milder phenotype and Down syndrome–associated moyamoya portending a more aggressive course. These findings need confirmation in a larger, multi-center cohort with longer duration of follow-up.