Factors Associated with Moyamoya Syndrome in a Kentucky Regional Population

Abstract

Our study aimed to report both new and previously identified conditions associated with moyamoya syndrome in a Western population and to present our outcomes after surgical treatment with indirect bypass. We performed a retrospective chart review of patients evaluated at our institution from June 2011 to June 2015 who were diagnosed with moyamoya. Data collected include patient demographics, presenting manifestations, vessels involved, comorbid conditions, abnormal laboratory values, treatments administered, and clinical outcomes. Thirty-one patients with moyamoya were enrolled (11 male and 20 female), with 84% Caucasian and 16% African-American. The most common comorbidity was hypertension in 61% of the patients. Coexisting autoimmune conditions were present in 26%, with another 13% having coexisting prothrombotic disorders. Diabetes mellitus was not found to correlate with the Suzuki grade of disease at presentation (P = .30). When noninvasive imaging was performed before the cerebral angiogram, the computed tomography angiography had a false-negative rate of 59%, and magnetic resonance angiography had a false-negative rate of 33%. Twenty-one patients underwent surgical intervention, 2 underwent intracranial stenting, and 19 underwent indirect bypass with encephaloduroarteriosynangiosis. At an average 28-month follow-up, all 15 patients who had an angiogram after intervention showed evidence of neovascularization. Autoimmune and prothrombotic disorders were found to be comorbid in patients with moyamoya at much higher rates than expected in the general population. Diabetes mellitus was not significantly correlated with Suzuki grade. Angiogram remains an important diagnostic modality when noninvasive imaging is negative for vasculopathy. We demonstrate excellent evidence of revascularization within 1 year with intracranial stenting and indirect bypass.