Complications of epilepsy surgery: A systematic review of focal surgical resections and invasive EEG monitoring

Purpose Underutilization of epilepsy surgery remains a major problem and is in part due to physicians' misconceptions about the risks associated with epilepsy surgery. The purpose of this study was to systematically review the literature on complications of focal epilepsy surgery. Methods A literature search was conducted using PubMed and Embase to identify studies examining epilepsy surgery complications. Abstract and full text review, along with data extraction, was done in duplicate. Minor medical and neurologic complications were defined as those that resolved completely within 3months of surgery, whereas major complications persisted beyond that time frame. Descriptive statistics were used to report complication proportions. Key Findings Invasive monitoring: Minor complications were reported in 7.7% of patients, whereas major complications were reported in only 0.6% of patients undergoing invasive monitoring. Resective surgery: Minor and major medical complications were reported in 5.1% and 1.5% of patients respectively, most common being cerebrospinal fluid (CSF) leak. Minor neurologic complications occurred in 10.9% of patients and were twice as frequent in children (11.2% vs. 5.5%). Minor visual field defects were most common (12.9%). Major neurologic complications were noted in 4.7% of patients, with the most common being major visual field defects (2.1% overall). Perioperative mortality was uncommon after epilepsy surgery, occurring in only 0.4% of temporal lobe patients (1.2%extratemporal). Significance The majority of complications after epilepsy surgery are minor or temporary as they tend to resolve completely. Major permanent neurologic complications remain uncommon. Mortality as a result of epilepsy surgery in the modern era is rare.