Last modified: 2018-09-09
Abstract
Introduction: Moyamoya disease is a progressive steno-occlusive arteriopathy that causes stroke and recurrent ischemic events (RIEs). MRI assessment of cerebrovascular reactivity (CVR) can be performed by measuring BOLD-MRI response to vasoactive stimuli. Negative BOLD-MRI reactivity, termed 'steal', predict RIEs in adults. Our objective was to determine whether 'steal' status is predictive of RIEs in childhood moyamoya.
Methods: We performed baseline and follow-up BOLD-CVR studies in a prospective cohort of children with moyamoya from 2000-2017. Children were followed until the date of RIE or end of follow-up. That hazard ratios for the time-varying steal status were calculated using univariate and multivariate Cox proportional hazard models.
Results: During a median (range) follow-up of 24 (0.4-140) months, of 37 children (57% female, median age 10.7 [1-17.7] years at baseline), 11 (30%) had RIEs. Children with positive steal, although non-statistically significant, were at a greater risk of experiencing RIEs with HR= 2.7 (95% CI 0.58-12.33, p=0.21). Age-adjusted multivariate Cox models showed a tendency toward significance for steal status (unilateral or bilateral) in predicting RIEs (HR=3, 95% CI 0.64-14.5, p=0.159). When considered separately, bilateral steal had the highest risk of RIEs followed by unilateral steal (HR=4, 95% CI 0.61-26.3, p=0.149 and HR=2.7, 95% CI 0.525-14, p=0.2335, respectively). Non-significant findings were obtained upon controlling for moyamoya etiology or surgical interventions.
Conclusions: Our preliminary findings suggest significantly reduced ischemic-free survival probabilities in children with moyamoya and negative BOLD-MRI reactivity. ‘Steal” status could be a potential predictor of RIE.