Unilateral combined bypass surgery might accelerate contralateral radiological progression in pediatric moyamoya disease

Abstract

Background: Surgical cerebral revascularization is recommended to treat pediatric moyamoya disease (MMD). However, whether unilateral combined bypass surgery would cause disease progression on the contralateral side is uncertain. The study aimed to investigate the vascular architecture and regional cerebral blood flow (rCBF) status of pediatric MMD patients after successful unilateral combined bypass surgery and to identify the possible risk factors. Methods: We reviewed the medical records and imaging data of pediatric MMD patients who underwent combined bypass surgery. Digital subtraction angiography (DSA) and magnetic resonance imaging (MRI) with arterial spin labelling (ASL) were performed for vascular architecture and cerebral blood flow investigation. Suzuki’s angiographic stage and moyamoya vessel grading system were both used. Progression was defined as an increase in either Suzuki stage or moyamoya vessel grade detected after unilateral surgery. Results: Twenty-seven successive patients with a median age of 8 years (Interquartile Range (IQR) 5-14 years old) were identified. On the non-operated (non-OP) side, eleven (40.7%) patients demonstrated progression, all of whom showed an increase in the moyamoya vessel grade, and five also displayed Suzuki stage progression. After contralateral surgery, rCBF barely changed on the non-OP side compared to pre-operation (49.6 vs 50.2 ml/100g/min, p=0.445). Moreover, contralateral progression was associated with the earlier Suzuki stage on the non-OP side (p = 0.007). Conclusions: Combined bypass surgery might accelerate the radiological progression on the contralateral side, which occurs before the decline of rCBF. Earlier Suzuki stage of the non-OP side was prone to rapid progression after unilateral combined revascularization.