Abstract TP449: Clinical and Angiographic Outcomes From Combined Direct and Indirect Bypass in Adult Patients with Moyamoya Disease: A Retrospective Study of 76 Procedures

Abstract

Objective: Surgical revascularization is the mainstay of treatment for moyamoya patients. This study was to evaluate the progonosis of combined direct and indirect procedure for moyamoya disease patients. Methods: 76 cerebral hemispheres from 64 adult moyamoya patients undergoing combined superficial temporal artery-middle cerebral artery (STA-MCA) anastomosis and encephalo-duro-myo-synangiosis (EDMS) were reviewed retrospectively. The mean follow-up period was 23±14m (6m-70m). CT or MR perfusion and Digital subtraction angiography (DSA) were performed for preoperative diagnosis and postoperative evaluation of cerebral perfusion and revascularization. mRS score, angiographic collateralization score, vessel diameter were recorded to measure neurological dysfunction, revascularization area and vascular compensatory effect respectively. Results: Among the 64 MMD patients, 69 hemispheres received combined direct and indirect operations; 7 hemispheres only received indirect operations. During our follow-up periods, neurological deficits of 57/64 patients (89.1%) were partially alleviated. mRS was significantly decreased after operations not only in all patients, but also in stroke subgroup or hemorrhage subgroup. Generally, good revascularization was established in most of the patients by combined bypass. 92.1% (70/74) sides was scored 2 and 77.6% (59/74) sides was scored 3 determined by angiographic collateralization score. Compared to the preoperative situations (2.60±0.65mm), the calibers of STA main trunk increased profoundly in at postoperative 10 days (3.32±1.05mm, p<0.05 versus pre-operation), and shrinked back to preoperative status at 6 months (2.24±1.00mm, p>0.05 versus pre-operation) and 12 months (2.36±0.73mm, p>0.05 versus pre-operation). Conclusion: Our findings strongly suggested that combined STA-MCA bypass and EDMS provided efficient revascularization and excellent results in preventing strokes and hemorrhage in adult patients. The direct STA-MCA bypass provided early augmentation of cerebral perfusion, whereas the indirect EDMS provided a more durable long-term revascularization, indicating a complementary relationship between the two revascularization methods.