Multiple arachnoid Membrane Opening to Promote Angiogenesis in Adult MMD patients after combine bypass surgery, a multicenter randomized controlled clinical trial

INTERVENTION: test group:Open arachnoid membrane during Moyamoya bypass surgery;control group:Do not open arachnoid membrane during Moyamoya bypass surgery; CONDITION: Moyamoya disease PRIMARY OUTCOME: Matsushima grade; SECONDARY OUTCOME: Surgical infection;subdural hematoma;hyper‐perfusion syndrome;new brain infarction; INCLUSION CRITERIA: Inclusion criteria 1. Age ranging between 30 and 65 years 2. Digital subtraction angiography (DSA) imaging studies demonstrating MMD or MMS 3. Modified Rankin Scale (mRS) score 0–2 4. A qualifying transient ischaemic attack (TIA) or ischaemic stroke occurred within the past 12 months 6. The most recent stoke occurred more than 3 weeks previously 7. The neurological deficit must have been stable for more than 1 month 8. No massive cerebral infarction (more than 50%of the MCA territory) demonstrable in a CT or magnetic resonance imaging (MRI) study 9. CTP demonstrates misery perfusion (MTT more than 4 s and rCBF (symptomatic side/asymptomatic side) < 0.95) 10. Must be competent to give informed consent 11. Must be legally an adult 12. Must be geographically accessible and reliable for follow‐up