Seizure Rates After Stereotactic Radiosurgery for Cerebral AVMs: A Single Center Study

Objectives: Seizure control after stereotactic radiosurgery (SRS) for arteriovenous malformations (AVMs) is an area of growing interest, with previous studies reporting up to 70% seizure freedom after treatment. The goals of this study were to identify specific patient and AVM characteristics associated with seizure presentation and seizure outcomes after SRS treatment.

Methods: A retrospective review of consecutive patients undergoing SRS for brain AVMs between 2009 and 2019 at our institution was conducted. Chi-squared and logistic regression analyses were utilized to identify patient and AVM factors associated with preoperative seizure presentation and development of new onset seizures after SRS.

Results: Two hundred ten consecutive patients presenting with AVMs treated with SRS were reviewed. Factors associated with seizure presentation included larger AVM size (P = 0.02), superficial venous drainage (P < 0.05), and parietal location (P = 0.04). Of 188 patients with follow-up (90%), 30 patients presented with seizures and 14 (47%) were seizure-free post-SRS. Of 158 patients presenting without seizure, 29 (18%) developed de novo seizures during follow-up. De novo post-SRS seizures were associated with prior craniotomy for resection of AVM (P = 0.04), post-treatment hemorrhage (P = 0.02), parietal location (P = 0.05), adverse effect requiring steroids (P < 0.01), and adverse effect requiring surgery (P < 0.01).

Conclusions: Seizures are a common presentation of brain AVMs and can be treated effectively with SRS. However, seizures can also be a complication of SRS and are associated with post-treatment hemorrhage, edema, and need for future open surgery.