Predictors of neoangiogenesis after indirect revascularisation in moyamoya disease: a 10-year follow-up study

Moyamoya disease (MMD) is a rare, chronic and progressive cerebrovascular disorder that is characterised by stenosis and occlusion of the distal carotid, proximal middle and anterior cerebral arteries and is accompanied by the development of small collateral vessel networks.1 Encephaloduroarteriosynangiosis (EDAS) has been a widely established treatment strategy for patients with MMD, however, the factors that affect the formation of collateral circulation after EDAS are unclear. We selected patients who had undergone cerebral angiography at least 5 years after the operation and investigated the relevant factors including RNF213 variation that could affect postoperative collateral formation. We identified all patients with MMD treated by EDAS at the Department of Neurosurgery in the Fifth Medical Center of Chinese PLA General Hospital, Beijing, China, from January 2002 through January 2015. Patients who received long-term postoperative digital subtraction angiography (duration ≥5 years after surgical revascularisation up to the latest follow-up angiography) were selected. All patients with MMD enroled in the study underwent EDAS. The basic clinical data were collected. The angiographic collateral grade was evaluated according to the system described in our recent study.2 Genotyping of p.R4810K was performed following the protocol described in our previous study.3 The last follow-up angiographies were conducted at least 5 years after EDAS. The development of …