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

Abstract

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.

Keywords: case series; giant aneurysm; rupture; systematic review; vascular disorders.

FIG. 1.

PRISMA flowchart. Data added to the PRISMA template (from Moher D, Liberati A, Tetzlaff J, Altman DG, The PRISMA Group. Preferred Reporting Items for Systematic Reviews and Meta-Analyses: The PRISMA Statement. PLoS Med. 2009;6[7]:e1000097) under the terms of the Creative Commons Attribution (CC BY-NC 2.0) License (https://creativecommons.org/licenses/by/2.0).

FIG. 2.

A 14-year-old boy presented with progressive headache and was found to have a giant, partially thrombosed left MCA aneurysm. He underwent superficial temporal artery (STA)–MCA bypass, clip ligation, and aneurysm resection. Preoperative anteroposterior (A) and lateral (B) angiograms are shown. The patient was treated with proximal clip occlusion, STA-MCA bypass, and aneurysm clip placement and resection to reduce mass effect while maintaining flow to nearby perforator arteries. Postoperative CT angiography (CTA) reconstruction (C) as well as coronal (D) and axial (E) CTA, demonstrated no residual aneurysm and reconstitution of distal flow through a patent bypass graft. The patient remained neurologically intact postoperatively.

FIG. 3.

An 11-year-old girl presented with progressive headache and was found to have an unruptured giant VBJ aneurysm, demonstrated by preoperative anteroposterior (A) and lateral (B) angiography. The patient underwent balloon occlusion testing of the bilateral VAs with a concurrent left ICA injection, which demonstrated adequate posterior circulation flow through the posterior communicating artery (C and D). After this radiographic test, the bilateral VAs were occluded. Postprocedural testing showed successful coil occlusion of both distal VAs (E and F) and she was discharged with an intact neurological examination.

FIG. 4.

Bar graphs showing the frequency of favorable outcomes for the six most common aneurysm locations, including the MCA (A), cavernous ICA (B), VA (C), VBJ or BA (D), supraclinoid ICA (E), and PCA (F), stratified by rupture status and treatment modality.