Anterior Temporal Lobectomy versus Selective Amygdalohippocampectomy: Comparative Meta-analysis of Surgical Interventions for Refractory Mesial Temporal Lobe Epilepsy

Introduction: Mesial temporal lobe epilepsy (MTLE)—a disorder in which seizure foci develop in the setting of hippocampal sclerosis—is the single most common cause of drug-resistant epilepsy (DRE). This pathology is responsible for approximately 30% of all surgical procedures performed for medically refractory epilepsy. While substantial evidence suggests that surgical intervention is effective for MTLE, further investigation is needed to determine whether selective amygdalohippocampectomy (SAH) or anterior temporal lobectomy (ATL) yields better seizure freedom and cognitive outcomes. As such, we provide a comprehensive overview of the current evidentiary base informing the selection of surgical interventions for MTLE by performing a three-database systematic review according to PRISMA guidelines.

Methods: Each database was queried using pre-determined search terms. Studies returned by each search were assessed for possible inclusion in the present study according to predefined inclusion and exclusion criteria. Where possible, meta-analysis was performed using the Mantel-Haenszel method to compare seizure and cognitive outcomes between SAH and ATL for MTLE. Throughout all statistical analyses, p < 0.05 was regarded as the threshold for statistical significance.

Results: Of the 4,317 studies screened, 30 reports featuring 3,298 patients met our predefined inclusion criteria. Meta-analysis revealed that the likelihood of seizure freedom following each of the two most common surgical procedures used for MTLE is roughly equivalent (OR: 0.7859, 95% CI [0.5779, 1.0688], I ² = 62%, p = 0.12). Overall, SAH did not prove superior to ATL (regarding visual field outcomes) when both transcortical and transsylvian SAH approaches were assessed on subanalysis (RR = 0.96, 95% CI [0.90, 1.03], I ² = 16%, p = 0.26). Comparison of cognitive/intellectual quotient outcomes following treatment of MTLE via SAL versus ATL using weighted SMDs proved equivocal for each categorical sub-analysis. Nonetheless, the test for the overall combined effect of the three subanalyses suggests that cognitive outcomes are superior following surgical management of MTLE when SAH is performed (SMD = −0.19, 95% CI [−0.35, −0.03, I ² = 0%, p < 0.05). Neither the subanalyses nor the overall combined meta-analysis appeared likely to have been influenced by heterogeneity. Egger’s plot demonstrates a fair degree of symmetry across studies and indicates a low risk for publication bias.

Conclusion: Although neither ATL nor SAH proved superior for surgical treatment of MTLE when assessed according to seizure or visual field outcomes, both surgical modalities appear safe and efficacious for patients with drug-resistant, medically refractory MTLE. Concerning cognitive outcomes, our analysis suggests that SAH may result in better cognitive recovery than ATL, which is logical given the more limited extent of the resection.

Publication History

Article published online:
07 February 2025