The aim of this study was to compare the efficacy of indirect and combined bypass surgery for treatment of adult moyamoya disease (MMD). The definition of combined bypass surgery is a combination of superficial temporal artery-middle cerebral artery (STA-MCA) anastomosis and indirect anastomosis. Development of collateral circulation after surgery was investigated.
Forty three patients (58 hemispheres) with MMD were followed by cerebral angiography for at least six months after surgery, between May 2002 and July 2011. Indirect and combined revascularization surgeries were performed in 33 and 25 cases, respectively. Good outcome was defined as more than group B, in accordance with the method suggested by Matsushima.
Development of collateral circulation was not affected by sex (p = 0.493), clinical features (p = 0.206), or Suzuki stage (p = 0.428). Based on postoperative cerebral angiography, the combined bypass surgery group showed a better angiographic outcome, than the encephaloduroarteriomyosynangiosis (EDAMS) group (p = 0.100, odds ratio [OR] 4.107, 95% confidence interval [CI] 0.700 - 24.096). The combined bypass group showed a better response than the encephaloduroarteriogaleosynangiosis (EDAGS) group (p = 0.088, OR 4.600, 95% CI 0.721 - 29.332). Similar responses were observed for EDAGS and EDAMS (p = 0.886, OR 1.120, 95% CI 0.239 - 5.251). The combined bypass group showed a better response than the indirect group (p = 0.064, OR 4.313, 95% CI 0.840 - 22.130).
Results of this study demonstrate that combined bypass results in better revascularization on angiographic evaluation in adult MMD. Therefore, among surgical procedures, combined bypass is a choice that can be recommended.