Can Combined Bypass Surgery at Middle Cerebral Artery Territory Save Anterior Cerebral Artery Territory in Adult Moyamoya Disease?

Background: Patients with moyamoya disease are frequently encountered with improved symptoms related to anterior cerebral artery territory (ACAt) and middle cerebral artery territory (MCAt) after bypass surgery at MCAt.
Objective: To evaluate hemodynamic changes in MCAt and ACAt after bypass surgery in adult moyamoya disease.
Methods: Combined bypass surgery was performed on 140 hemispheres in 126 patients with MCAt symptoms. Among them, 87 hemispheres (62.1%) accompanied preoperative ACAt symptoms. Clinical, hemodynamic, and angiographic states were evaluated preoperatively and approximately 6 months after surgery.
Results: Preoperative symptoms resolved in 127 MCAt (90.7%) and 82 ACAt (94.3%). Hemodynamic analysis of total patients showed a significant improvement in MCAt basal perfusion and reservoir capacity ( P < .001 and P = .002, respectively) and ACAt basal perfusion ( P = .001). In a subgroup analysis, 82 hemispheres that completely recovered from preoperative ACAt symptoms showed a significant improvement in MCAt basal perfusion and reservoir capacity ( P < .001 and P = .05, respectively) and ACAt basal perfusion ( P = .04). Meanwhile, 53 hemispheres that had never experienced ACAt symptoms significantly improved MCAt basal perfusion and reservoir capacity ( P < .001 and P = .05, respectively); however, no ACAt changes were observed. A qualitative angiographic analysis demonstrated a higher trend of leptomeningeal formation from MCAt to ACAt in the former subgroup ( P = .05). During follow-up, no ACAt infarctions were observed.
Conclusion: Combined bypass surgery at MCAt resulted in hemodynamic improvements in ACAt and MCAt, especially in patients with preoperative ACAt symptoms.
(Copyright © 2017 by the Congress of Neurological Surgeons)