Adult-onset Moyamoya Disease: Clinical Features and Prognosis

ABSTRACT

BACKGROUND: The age distribution of patients with moyamoya disease (MMD) forms two characteristic peaks in children and adults. It is well known that hemorrhagic presentation is more frequent in adults, while hemorrhage is rare in children. There is controversy in the management of adult-onset MMD and its natural course is not well defined. We investigated the clinical features and outcomes of adult onset MMD to clarify its characteristics. METHODS: Fifty patients with MMD whose first manifestation appeared later than 15 years of age were studied retrospectively. The first manifestations were divided into ischemic and hemorrhagic categories. The types of reattack and their frequencies according to treatment type, as well as the differences between probable (unilateral) and definite (bilateral) MMD, and current clinical outcomes by the Modified Rankin Scale were investigated. RESULTS: The mean follow-up duration was 24.4+/-25.9 months. The female/male ratio was 1.5. The most frequent age of onset was in the 4th decade. Ischemia was more frequent (58%) than hemorrhage (40%) at the initial presentation. Reattack occurred in 20 (41%) patients and more frequently in the ischemic type (55%) than the hemorrhagic (20%). Patients with probable MMD had a later onset age (39 vs. 31.5 years old) and more frequent reattacks (50%) than patients with definite MMD (38%). Reattack occurred in 2 patients (9.5%) among 21 patients who received surgical revascularization during mean follow-up of 15.1+/-21.7 months. One patient had ischemic reattack and the other had hemorrhagic reattack after operation. Thirty five (71%) of 50 patients had good outcomes but 3 patients with hemorrhagic reattacks had poor outcomes (6%). CONCLUSIONS: Probable and definite MMD have some differences in clinical features such as onset age and reattack. Regardless of initial manifestations, most of the adult MMD patients had good outcomes. However, patients with recur-rent attacks had worse outcomes than those without reattacks, especially of the hemorrhagic type. Therefore, revention of rebleeding should receive more attention in the management of adult MMD.