Indirect revascularization in Moyamoya vasculopathy: clinical and radiological outcomes of multiple burr hole surgery

Abstract

Purpose Moyamoya vasculopathy is a progressive cerebrovascular disease characterized by stenosis of the intracranial internal carotid arteries, leading to chronic cerebral ischemia. Indirect revascularization techniques, such as multiple burr hole surgery, aim to promote collateral vessel formation and improve cerebral perfusion. This study evaluates the clinical and radiological outcomes of multiple burr hole surgery in a diverse Belgian patient population with Moyamoya vasculopathy. Methods A retrospective single-center cohort study was conducted, including 15 patients (22 hemispheres) who underwent multiple burr hole surgery between 2007 and 2024. Clinical outcomes, stroke recurrence, and magnetic resonance (MR) perfusion parameters-relative cerebral blood volume (rCBV) and relative time to peak (rTTP)-were analyzed pre-and postoperatively in five predefined brain regions. Of the 22 hemispheres, raw MR perfusion data were available in 11 (50%), limiting subgroup analyses and statistical power. Results Postoperative MR perfusion imaging demonstrated significant improvements in rCBV and rTTP in the frontal, parietal, and occipital lobes of surgically treated hemispheres (p < 0.05) after a median follow-up of 21 months. No significant changes were observed in deep brain structures (thalamus and basal ganglia) or the contralateral hemisphere. Clinically, one patient experienced a recurrent ischemic stroke during follow-up. One patient developed transient postoperative paresthesia, and one patient suffered fatal cerebral edema. Conclusion Multiple burr hole surgery has the potential to be an effective technique for enhancing cerebral perfusion in selected patients with Moyamoya vasculopathy. The observed improvements in superficial cortical perfusion support its role as an alternative to direct revascularization in selected cases. Future long-term follow-up studies are essential to assess sustained benefits and refine patient selection criteria for indirect revascularization.