Clinical features and endovascular treatment of ruptured peripheral cerebral aneurysms associated with moyamoya disease: an 8-year single-center experience.

Objective: Ruptured peripheral cerebral aneurysm (PPCA) associated with moyamoya disease (MMD) is rarely reported, and its optimal treatment remains controversial. This study aims to present the clinical characteristics, treatment strategies, and outcome predictors of this rare clinical entity.

Methods: A retrospective review of patients with hemorrhagic MMD from January 2013 to December 2020 was performed. All medical records were independently compiled and reviewed.

Results: Twenty-three patients were identified, 56.5% of whom were female. The mean age was 45.9 years with a peak age of onset of 51-60 years. Most patients (65.2%) developed intraventricular hemorrhage with or without intracerebral hemorrhage. These aneurysms were frequently located on the anterior (26.1%) and posterior (43.5%) choroidal arteries. Sixteen (69.6%) aneurysms were embolized and the remaining 7 (30.4%) were managed conservatively due to approach inaccessibility. Good outcomes were achieved in 82.6% of all cases, with 81.3% for embolization and 85.7% for observation. Complete occlusion was observed in all 16 aneurysms embolized. Of the conservatively treated aneurysms, 1 (14.3%) re-ruptured, 1 (14.3%) decreased in size, 2 (28.6%) disappeared, and 3 (42.8%) remained stable in size. Aneurysm rebleeding was associated with an unfavorable outcome (P = 0.026).

Conclusions: PPCA should be considered in the differential diagnosis of hemorrhagic MMD. Aneurysm rebleeding appears to be a potential predictor of poor outcome and therefore aggressive intervention should be advocated. Endovascular embolization may be safe and feasible, and conservative observation should be carefully chosen given the high risk of aneurysm re-rupture.