Adult moyamoya after revascularization

Although cerebral revascularization is an accepted treatment for moyamoya, the precise impact of direct or indirect bypass methods on subsequent event rates is infrequently addressed in adult cohorts. We reviewed 45 consecutive adults with 69 hemispheres affected by moyamoya. We evaluated stroke and hemorrhage rates prior to and following revascularization. Direct revascularization was performed for 35 hemispheres (51 %) in 29 patients (64 %). The annual stroke, hemorrhage and overall event rates in this cohort diminished from 8.9 %, 2.0 %, and 11 % per hemisphere-year to 4.5 %, 0 %, and 4.5 % per hemisphere-year after treatment, respectively (p = 0.06). Excluding perioperative events, no events occurred over 41.1 hemisphere-years of follow-up (p = 0.0017). After a mean clinical follow-up period of 1.3 years, 72 % of patients were improved, 24 % the same, and 3 % worse in this cohort. Indirect revascularization was performed for 18 hemispheres (26 %) in 13 patients (29 %). The annual stroke, hemorrhage and overall event rates were 13 %, 0 %, and 13 % per hemisphere-year prior to treatment, and 6.8 %, 4.5 %, and 11 % per hemisphere-year after treatment, respectively (p = 0.67). Excluding perioperative events, the overall annual event rate was 7.1 % (p = 0.69). After a mean clinical follow-up of 2.7 years, 46 % of patients were improved, 38 % were the same and 15 % were worse. Direct revascularization is the optimal choice to prevent subsequent events in adult patients with moyamoya. A favorable impact of indirect revascularization was less clear in this cohort, and should be reserved for patients with an inadequate donor vessel.