Stereo‐electroencephalography‐guided radiofrequency thermocoagulation in patients with focal epilepsy: A systematic review and meta‐analysis.

Summary: Objective: Despite the increasing number of studies reporting results of stereo‐electroencephalography (SEEG)–guided radiofrequency‐thermocoagulation (SEEG‐guided RF‐TC) in the treatment of patients with drug‐resistant focal epilepsy, the exact efficacy of this approach remains unclear. The seizure‐freedom rate varies greatly across studies and the factors associated with efficacy have not been formally investigated. Methods: All prospective or retrospective studies reporting efficacy and/or safety of SEEG‐guided RF‐TC in patients with drug‐resistant focal epilepsy were included. The primary outcome was the seizure‐free rate 1 year after the procedure. Secondary outcomes were (1) the responder rate 1 year after the procedure and (2) the proportion of patients with permanent neurologic deficit 1 year after the procedure. Each outcome was assessed in all patients and in 4 groups of patients defined by the etiology of epilepsy. Each outcome was pooled using inverse variance weighting, logit transformation of proportion, and a random‐effects model. Results: No prospective study was identified and a total of 6 retrospective studies, reporting efficacy and safety data of 296 patients, were included. The pooled rate of permanent neurologic deficit was 2.5% (95% confidence interval [CI] 1.2%‐5.3%), without heterogeneity across studies. In contrast, both the seizure‐free and responder rates varied greatly across studies, and statistical heterogeneity was high. The pooled seizure‐free and responder rates were 23% (95% CI 8%‐50%) and 58% (95% CI 36%‐77%), respectively. Both for the seizure‐free and responder rates, the greatest efficacy was observed in patients with periventricular nodular heterotopia and the lowest in patients with normal magnetic resonance imaging (MRI) findings. Significance: SEEG‐guided RF‐TC is a safe procedure with low risk of complications. In contrast, the level of evidence regarding its efficacy remains low. Better identification of factors associated with seizure outcome are needed. [ABSTRACT FROM AUTHOR]