Indications and results of direct cerebral revascularization in the modern era

Background There has been a progressive decrease in the indications for cerebral revascularization during the past 30 years, particularly with the advance of endovascular techniques. Our objective was to define indications for and evaluate outcomes of patients treated with bypass surgery in the modern endovascular era. Methods We retrospectively reviewed the charts of all patients who underwent direct cerebral revascularization procedures between January 2006 and March 2013. Results In total, 121 patients underwent 131 direct microsurgical revascularization procedures. The indications for bypass surgery were moyamoya angiopathy (40 patients, 47 bypasses), complex aneurysms (54 patients, 56 bypasses), and occlusive vascular disease (27 patients, 28 bypasses). Revascularization resulted in improvement of symptoms in 77.5% of patients with moyamoya angiopathy (mean clinical follow-up 18.8 months) and 55.5% of patients with occlusive vascular disease (mean clinical follow-up 10.4 months). Among the aneurysm patients treated with revascularization, 81.5% had a favorable outcome (Glasgow Outcome Scale score 4-5) at long-term follow-up (mean clinical followup 18.5 months). Conclusions Although microvascular cerebral revascularization is no longer performed as commonly as in the past, it remains an essential part of the skill set required to treat select vascular pathologies. Complex aneurysms are the single largest indication for direct bypass procedures. Moyamoya disease is by far the largest indication if indirect bypass procedures are included in the analysis. In experienced hands, the morbidity and mortality of patients undergoing cerebral revascularization procedures are low and long-term outcomes generally excellent.