Medical vs invasive therapy in AVM-related epilepsy

Objective: To compare invasive arteriovenous malformation (AVM) therapy to conservative management using only antiepileptic drugs (AEDs) for achieving seizure freedom in patients with AVM-related epilepsy. Methods: We searched Medline, Embase, and Cochrane Central up to June 2015 using epilepsy and AVM Medical Subject Headings and keywords. We included original research involving controlled observational cohort studies or randomized controlled trials (RCTs) comparing seizure outcomes between invasive AVM treatments vs AED management alone, and uncontrolled case series of invasive AVM therapy for seizures that contained ≥20 patients. The estimates of seizure freedom were pooled using meta-analysis for the controlled trials, while the estimates for the case series were evaluated using descriptive statistics. Results: Of 2,166 identified abstracts, 98 were reviewed in full text, of which 31 were included in the final dataset. We identified 2 controlled observational studies (n 106 patients) and 29 uncontrolled case series. We identified 1 RCT but it did not report seizure outcomes. The pooled risk ratio for seizure freedom in controlled studies (0.99; 95% confidence interval [CI] 0.69, 1.43) did not indicate superiority to either approach. Seizure freedom in case series varied from 19% (95% CI 11, 30%) to 95% (95% CI 76, 99%) at last follow-up. Conclusions: There is insufficient evidence available to determine if invasive AVM management is superior to AED only for controlling seizures. An RCT of interventional vs medical management using standardized epilepsy-specific presurgical protocols is warranted.