Abstracts

Rationale: To comprehensively examine the outcomes of resective surgery for focal epilepsy, summarize evidence which patients benefit the most and discusses possibilities why epilepsy surgery is still not universally recommended. Methods: Medline and Cochrane databases were searched in June 2014 for randomized controlled trials, meta-analyses, systematic reviews and large retrospective case series (>300 patients) using Mesh terms and indexed text terms. 55 articles were included. Sub-populations and prognostic factors were identified. Systematic reviews for outcomes beyond seizures such as cognitive, psychiatric, quality of life and psycho social outcome were included. Results: Two small randomized controlled trials in 118 patients report significantly greater seizure freedom with surgery as compared to continued medical treatment (p < 0.001). Nine systematic reviews and two large case series of medically refractory patients, report a seizure free outcome in 34%-74% of patients, with a median of 62.4%. The remainder of systematic reviews and meta-analyses examine sub-populations. Patients with extratemporal and/or non-lesional epilepsy benefit less in terms of seizure freedom than patients with temporal epilepsy or MRI abnormalities. Children have similar seizure free outcome as adults. Hippocampal sclerosis and benign tumor have a better outcome than other pathologies. Varying surgical procedures such as selective amygdalo-hippocampectomy or temporal lobectomy for temporal lobe epilepsy show differences in seizure and neuropsychological outcome. Perioperative mortality is low (0.1-0.5%) and the most reported neurological morbidity is visual field defects after temporal lobe resection. Quality of life improves after surgery, but improves the most in those patients who succeed in becoming seizure free after surgery. Conclusions: Among patients with drug-resistant focal epilepsy, resective epilepsy surgery, compared to continued medical treatment, was associated with greater reductions in seizure frequency. Further investigation is necessary to determine long-term cognitive, psychiatric, psychosocial and quality of life outcomes. Surgical treatment maybe underutilized despite the evidence. Reasons for not referring patients to major epilepsy centers need to be addressed. Funding: No funding has been received in support of this abstract.