Surgical outcomes in stereoelectroencephalography versus subdural grids: a systematic review & meta-analysis

Invasive extra-operative monitoring for drug-resistant epilepsy is primarily conducted using stereo-electroencephalography (SEEG) and subdural grids (SDG). This study aims to provide a comprehensive comparison of the two methods. This systematic review was conducted in accordance with PRISMA guidelines. A comprehensive literature search was performed using PubMed, Scopus, Web of Science, and the Cochrane Database. The primary outcomes assessed included postoperative seizure outcome, complications, neurological deficits, and pain. All original English-language studies published up until January 2025 were reviewed, and the risk of bias was evaluated using the Newcastle-Ottawa Scale. Seven studies involving a total of 1,156 patients who underwent SEEG and 737 patients who underwent SDG were included. The pooled analysis demonstrated higher odds of seizure freedom in the SEEG group compared with the SDG group (OR = 1.72, 95% CI: 1.33–2.22). However, the included studies compared clinically distinct patient populations with different indications for invasive monitoring and surgical pathways, which may have influenced seizure outcomes. Across the included studies, SEEG was consistently associated with lower infection rates and reduced postoperative analgesic requirements, while rates of hemorrhage and neurological deficits were generally comparable between groups, with some studies reporting slightly higher hemorrhage rates in SEEG cohorts. SEEG was associated with higher odds of seizure freedom following epilepsy surgery; however, this finding should be interpreted with caution because the included studies compared clinically distinct patient populations with different indications for invasive monitoring, surgical pathways, and resection rates. The available evidence suggests lower infection rates and reduced postoperative analgesic requirements with SEEG, whereas findings regarding hemorrhage and neurological deficits were variable across studies. Further studies with larger, more comparable patient populations are needed to better define procedure-specific risks and outcomes.