Comparative Outcomes of Unilateral vs Bilateral Revascularization in Moyamoya Disease: A Multicenter Retrospective Study

BACKGROUND AND OBJECTIVES: Moyamoya disease (MMD) is characterized by progressive steno-occlusion of the internal carotid arteries, leading to compensatory collateral vessel formation. The optimal surgical approach for MMD remains debated, with bilateral revascularization potentially offering more comprehensive protection but involving more extensive surgery compared to unilateral revascularization. This study aims to compare bilateral revascularization and unilateral revascularization short-term safety profile in the treatment of MMD. METHODS: This multicenter retrospective study included patients with MMD who underwent surgical revascularization at 13 academic institutions. Patients were categorized into unilateral and bilateral revascularization groups. Data collected included demographics, clinical characteristics, and outcomes. Propensity score matching was used to balance baseline characteristics. Statistical analyses were conducted using Stata (V.17.0; StataCorp). RESULTS: A total of 497 patients were included, including 90 who had bilateral revascularization and 407 who had unilateral revascularization. Bilateral revascularization was associated with more perioperative asymptomatic strokes (10% vs 2.4%; odds ratio [OR] 4.41, 95% CI 1.73 to 11.19, P = .002) and higher rates of excellent functional outcomes (modified Rankin Scale 0-1) at discharge (92.2% vs 79.1%; OR 3.12, 95% CI 1.39 to 7, P = .006). After propensity score matching, 57 matched pairs were analyzed. There was a higher rate, though not statistically significant difference, of perioperative stroke in the bilateral revascularization group (15.7% vs 8.7%; OR 1.95, 95% CI 0.61 to 6.22, P = .26). No significant differences were noted in modified Rankin scale 0 to 1 and 0 to 2 scores at discharge, National Institute of Health Stroke Scale at discharge, intraoperative complications, or length of hospital stay. The follow-up stroke rates were also not significantly different (OR 0.40, 95% CI 0.11 to 1.39, P = .15). CONCLUSION: This study found no significant differences between bilateral and unilateral revascularization in MMD. Patients who had bilateral revascularization had higher tendency of perioperative stroke, though not statistically significant. Further prospective studies are needed to validate these results.