2076 The Use of the MMA in EC-IC Bypass for Moya Moya Disease: A Case Series

INTRODUCTION: Extracranial-intracranial (EC-IC) bypass in the treatment of Moyamoya disease traditionally involves a Superficial Temporal Artery (STA) to Middle Cerebral Artery (MCA) bypass. However, there are rare cases in the Moya Moya population wherein the STA is absent. We present our experience in using the Middle Meningeal Artery (MMA) in 5 cases as a viable donor vessel in such situations. METHODS: A retrospective case series was undertaken to investigate long term outcomes in patients who underwent MMA-MCA bypass for surgical treatment of Moya Moya disease. RESULTS: A total of 5 patients, including pediatric patients (n=3) with an average age of 10.3 years old and adult patients (n=2) with an average age of 40 years old, underwent surgical revascularization with an MMA-MCA anastomosis. The average follow up period was 4.8 years with 4 out of 5 grafts patent at the most recent follow up study. Case 4 - A 8-year-old male with history of sickle cell anemia and ischemic Moya Moya disease underwent a left MMA-MCA anastomosis in 2016. Preoperative angiogram demonstrates an absent STA but prominent MMA. Intraoperative photographs demonstrate careful preservation and preparation of MMA, followed by anastomosis to an M4 branch of the MCA with good flow on indocyanine green (ICG) angiography, and a 8 year follow-up DSA demonstrating the patency of the MMA graft. CONCLUSIONS: MMA-MCA anastomosis can be an option for revascularization in Moya Moya disease in cases in which the STA is absent.