Abstract
We analyzed the effect of superficial temporal to middle cerebral artery (STA-MCA) bypass to prevent future strokes based on the data of the clinical course and the course of the collateral circulation.
Thirty-five patients with hemorrhagic type moyamoya disease were examined during the follow-up period with a mean of 6.3 years after the initial intracranial hemorrhage. Eighteen patients were conservatively managed, 12 patients underwent STA-MCA bypass, and the last 5 patients underwent encephaloduroarteriosynangiosis (EDAS). The ophthalmic artery flow was examined as the collateral circulation using the color Doppler flow imaging (CDFI).
During the follow-up period, 13 patients (43%, 5.86%/patient/year) experienced a cerebral event such as ischemia or rebleeding. The incidence of a future stroke event in the patients treated with STA-MCA bypass (p<0.05) was significantly lower than that in the patients conservatively managed or treated with EDAS using the log-rank test. At the initial stage, the hemorrhagic side ophthalmic artery CDFI showed a high-flow pattern and a significantly high peak systolic flow velocity (Vs) compared to the opposite side (p<0.05). During the follow-up period, in the conservatively managed patients, the Vs value did not change markedly. On the other hand, in the patients treated with STA-MCA bypass, the Vs value decreased significantly (p<0.05).
Clinical symptoms and ophthalmic artery CDFI findings confirmed that STA-MCA bypass in patients with hemorrhagic type moyamoya disease prevents future strokes.
