Surgical Outcomes of Laser Interstitial Thermal Therapy for Temporal Lobe Epilepsy: Systematic Review and Meta-analysis

Abstract

Background: Laser interstitial thermal therapy (LITT) has emerged as a safe and effective approach to the treatment of temporal lobe epilepsy (TLE). The relationship of ablation volume with postoperative outcomes remains an area of contention.

Methods: We conducted a systematic review and meta-analysis of available studies on LITT for TLE. Seizure freedom and complication rates were meta-analyzed using a random-effects model. Meta-regression of seizure freedom rate for the overall cohort and mesial temporal sclerosis (MTS) subset (n = 384) was performed adjusting for overall ablation volume as well as percentage of hippocampal and amygdala ablation.

Results: A total of 13 studies (551 patients) were analyzed. Pooled mean ablation volume was 5376 mm³ (range, 2900-7110 mm³), pooled mean hippocampal ablation was 67.5% (range, 56%-78.3%) and pooled mean amygdala ablation was 58.8% (range, 43%-73.7%). Overall seizure freedom rate was 58% (95% confidence interval [CI], 54%-62%) and was not significantly associated with total ablation volume (P = 0.42), hippocampal ablation (P = 0.67), or amygdala ablation (P = 0.33). Seizure freedom rate for patients with MTS was 66% (95% CI, 58%-74%) and was also not found to be significantly associated with total ablation volume (P = 0.15), hippocampal ablation (P = 0.73), or amygdala ablation (P = 0.43). Overall complication rate was 17% (95% CI, 13%-22%).

Conclusions: The findings show a pooled seizure freedom rate of 58% for all patients with TLE and 66% for patients with MTS undergoing LITT. The evidence is insufficient to support a significant relationship of seizure freedom rate with total ablation volume as well as hippocampal or amygdala ablation.

Keywords: Amygdala; Epilepsy surgery; Hippocampus; Mesial temporal sclerosis; Meta-analysis; Seizure freedom; Systematic review.