Rupture risk and outcomes of giant aneurysms in pediatric patients: a multi-institutional case series and systematic review.

Objective: Giant aneurysms in pediatric patients are vascular lesions that can cause significant neurological morbidity and mortality. Their rarity has precluded large cohort studies to inform their management. The objective of this study was to understand the clinical course and outcomes of giant aneurysms in pediatric patients.

Methods: The authors performed a multi-institutional cohort study of cases from Boston Children's Hospital and Barrow Neurological Institute, as well as a systematic review and pooled cohort analysis of previously reported cases using descriptive statistics and multivariate regression modeling.

Results: Fifteen patients were included in the multi-institutional cohort, and an additional 88 patients were included from 14 series, yielding 103 patients within the pooled cohort. Among the pooled cohort, the most common aneurysm locations were in the middle cerebral artery (36%), internal carotid artery (27%), vertebral artery (11%), and vertebrobasilar junction (8%). Within 69 cases containing radiographic data in the analysis, 38% of aneurysms were saccular. Twenty-eight cases presented with aneurysm rupture (28%), including 0% of cavernous carotid aneurysms, 26% of other anterior circulation aneurysms, and 44% of posterior circulation aneurysms (p = 0.003). In multivariate analysis, posterior circulation location (OR 2.66, 95% CI 1.03-6.86) and younger age (OR 0.90 per year, 95% CI 0.81-1.00) were associated with aneurysm rupture presentation. Most cases were treated (97%) rather than observed (3%). The mortality rate was 3% for unruptured aneurysms and 18% for ruptured aneurysms. A favorable neurological outcome occurred in 80% of unruptured aneurysm cases and 54% of ruptured cases. In multivariate analysis, unruptured aneurysm presentation (OR 3.74, 95% CI 1.24-11.29) and endovascular treatment modality (OR 5.05, 95% CI 1.56-16.29) were associated with a favorable outcome.

Conclusions: Giant aneurysms are rare entities in pediatric patients that are unlikely to be discovered incidentally and usually merit treatment. Most patients survive with good neurological outcome, even in ruptured aneurysm cases. These data reveal that posterior circulation location and younger age are risk factors that correlate with an increased risk of aneurysm rupture.