Efficacy of STA-MCA bypass surgery in moyamoya angiopathy: long-term follow-up of the Caucasian Krupp Hospital cohort with 81 procedures

Abstract

Background: Despite the consensus on the efficacy of revascularizing surgery in moyamoya angiopathy (MA) in Asia, the indication in Caucasian moyamoya patients is controversially discussed.

Objective: The efficacy of revascularizing surgery in adult European patients with MA should be clarified.

Methods: This study retrospectively analyzed the rate of further strokes and hemorrhages as well as MRI and Duplex ultrasound features during long-term follow up after STA-MCA bypass.

Results: Eighty-one STA-MCA bypass procedures in 54 patients with MA operated in one single German institution were analyzed. All 54 patients (100%) were Caucasians. After two diffusion restricted spots in MRI perioperatively (2.5%) and short-lasting symptoms directly after surgery, no patient experienced further new symptoms related to stroke or hemorrhages nor no new gliotic scars or microbleeds on MRI for 38.2 months. Duplex ultrasound 3 months after surgery documented bypass patency in 100% and sonographic sign for good relevance of the bypass in 96.2%. In addition, the diameter of the donor vessel had increased in 89.9% as an indicator for the relevance of the bypass. Semi-quantitative analysis of perfusion changes in the operated hemispheres demonstrated an increase in perfusion in the MCA territory in 56 of 74 (75.7%) hemispheres 36.7 months after surgery. In MRA images, a reduction of typical moyamoya collaterals was found in 65 of 79 hemispheres (82.3%) after a mean of 37.2 months.

Conclusion: Direct STA-MCA bypass is an effective therapy in Caucasian patients with hemodynamically compromised MA.

Keywords: Bypass surgery; Efficacy; Europeans; Moyamoya angiopathy; Stroke.