Long-term effects of revascularization on brain volume and clinical outcomes in pediatric moyamoya disease.

Abstract

Objective: The long-term effects of revascularization surgery on the developing pediatric brain in patients with moyamoya disease (MMD) are yet to be fully understood. In this study, the authors aimed to evaluate long-term brain volume changes following revascularization surgery and to explore their clinical significance in this patient population.

Methods: This retrospective multicenter study included data collected between January 2011 and June 2021 at three hospitals. Changes in lateral ventricle and intracranial space volumes were quantified by comparing preoperative MRI studies with those obtained during the final follow-up at least 1 year postsurgery. Associations between these volumetric changes and clinical as well as radiological factors were analyzed.

Results: The study included 61 pediatric patients with MMD. Following revascularization surgery, the mean absolute volume of the lateral ventricles significantly increased from 9.7 to 11.0 cm3 (p < 0.0001), and the intracranial space volume increased from 812.0 to 834.4 cm3 (p < 0.0001). A weak correlation was identified between follow-up duration and volume changes in both the lateral ventricles (r = 0.26, p = 0.04) and the intracranial space (r = 0.28, p = 0.03). Approximately 75% of cases showed a greater rate of ventricular volume increase relative to intracranial space expansion, with 16.4% (10 cases) exhibiting disproportionately larger lateral ventricle enlargement exceeding 50%. Univariate analysis revealed that combined revascularization, compared with indirect anastomosis alone, resulted in significantly greater lateral ventricle enlargement (p = 0.003). Additionally, severe headaches that persist after surgery (p = 0.0008) and new cerebral infarction during the long-term follow-up (p = 0.028) were significantly associated with increased lateral ventricle volume. Multivariate analysis identified an age > 4 years, combined revascularization, severe postoperative headaches, and new cerebral infarction during the long-term follow-up as independent predictors of postoperative ventricular enlargement.

Conclusions: This study revealed a previously unrecognized pattern of gradual lateral ventricle volume changes in pediatric patients with MMD following revascularization surgery. These findings underscore the importance of long-term MRI monitoring to detect subtle but clinically relevant morphological changes. The results suggest that vigilant monitoring of these changes could help optimize clinical outcomes and improve quality of life in this vulnerable patient population.