Predictive Factors of Postoperative Seizure for Pediatric Patients with Unruptured Arteriovenous Malformations.

BACKGROUND: Seizure is the second-most common presentation in patients with arteriovenous malformations (AVMs) and superimposes a significant burden on pediatric patients. Postoperative seizure risk in unruptured AVMs is underreported in the pediatric AVM literature. We aimed to characterize and identify predictive factors for postoperative seizures in this study.

METHODS: We performed a retrospective review of all surgically treated pediatric patients with unruptured AVM at our institution from 2001 to 2014. Patients younger than 18 years of age were included. Baseline variables was compared against our outcome of interest, which was defined as patients with or without follow-up seizures. Multivariable Cox regression was performed to identify potential predictive factors.

RESULTS: The average age of all patients was 13.1 years, and 68.2% were male. Nine patients were asymptomatic (13.6%), and seizure presentation occurred in 57.6% (n = 38). During an average follow-up of 4.2 years, 12 (18.2%) patients experienced postoperative seizures, with 5 (17.9%) of 28 patients with seizures being de novo. In patients with seizure presentation, 81.6% were completely seizure-free throughout follow-up. In multivariable analysis, larger AVM size (hazard ratio [HR] 1.63, P = 0.023) and temporal location (HR 8.35, P = 0.007) were found to increase the risk of follow-up seizures. On the contrary, seizure presentation (HR 1.91, P = 0.369) and postoperative infection (HR 2.37, P = 0.265) were not associated.

CONCLUSIONS: Surgery may eliminate most seizures with low risk of inducing de novo seizures in pediatric patients with unruptured AVM. Predictive factors for postoperative seizures included large AVM size and temporal location. For selected unruptured AVMs with small size and nontemporal location, consideration of surgery as primary treatment for persistent seizures is a reasonable option.