Clinical and angiographic outcomes after combined direct and indirect bypass in adult patients with moyamoya disease: A retrospective study of 76 procedures

Abstract

Abstract. The present retrospective study was performed to evaluate the clinical outcome, as well as post-operative collateral formation and revascularization patterns in combined bypass. Surgical revascularization has been the mainstay of treatment for moyamoya patients. A total of 76 hemispheres from 64 moyamoya patients undergoing combined superficial temporal artery-middle cerebral artery (STA-MCA) anastomosis and encephalo-duro-myo-synangiosis (EDMS) were retrospectively reviewed. Computed tomography perfusion and DSA were routinely performed. Modified Rankin scale (mRS) scoring and Kaplan-Meier analysis were performed, and post-operative collateral grading on digital subtraction angiography (DSA), reconstruction patterns and vessel diameter were measured to evaluate the revascularization area and vascular compensatory effect. During the follow-up period, the chief complaint was partially alleviated in 57/64 patients (89.1%). In all patients, mRS was significantly decreased after the operation. Good revascularization was established in most patients at 6 months after the surgery: 92.1% of sides were scored as 2 and 77.6% were scored as 3 by post-operative collateral grading on DSA. Dominant collateral revascularization originating from EDMS was more frequent than that from STA-MCA anastomosis (31 vs. 19 hemispheres) at 6-month follow-up. Morphologically, the calibers of the STA main trunk (2.60±0.65 mm) increased profoundly at the first 10 post-operative days (3.32±1.05 mm) and shrank back to pre-operative status at 6 months (2.20±1.01 mm) and 12 months (2.36±0.73 mm) according to DSA examination. Middle meningeal artery (MMA) and deep temporal artery (DTA) demonstrated continuous augmentation during the follow-up time (from 1.30±0.46 to 1.87±0.69 mm for MMA and 1.11±0.25 to 2.11±1.16 mm for DTA). These results strongly suggested that combined STA-MCA bypass and EDMS provided efficient revascularization and reduced acute cerebral events. 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 association between the two revascularization methods.

Angiographic Outcomes of Direct and Combined Bypass Surgery in Moyamoya Disease

“…Meanwhile, indirect surgery takes more time to improve cerebral blood flow, which requires approximately about 3 months for neoangiogenesis from connective tissue (4, 19). DB provided early augmentation of blood flow, whereas the indirect surgery provided a more durable long-term neoangiogenesis, indicating a complementary association between the two procedures (29). Theoretically, CB may have better angiographic outcomes than DB.…”

Moyamoya Disease: A Review of Current Literature

“…Combination revascularization procedures combine both direct and indirect revascularization. Direct bypass provides immediate cerebral perfusion, whereas the indirect component leads to a sustained revascularization response [ 46 ]. In the perioperative period, normocapnia, adequate body fluid balance, and blood pressure should be maintained to avoid ischemic complications [ 31 ].…”

Direct Bypass Surgery Vs. Combined Bypass Surgery for Hemorrhagic Moyamoya Disease: A Comparison of Angiographic Outcomes

“…A growing number of studies have suggested that combined bypass surgery provided better revascularization for the general MMD population than direct bypass alone, because the surgical effect was double-secured by both instant increase of blood flow from direct anastomosis and subsequent spontaneous ingrowth of collaterals from the indirect bypass(16–20). However, it was also agreed that treating hemorrhagic MMD with indirect bypass surgery alone might not receive satisfying results (21–23).…”