Review compares surgical and neurostimulation outcomes in temporal lobe epilepsy

Temporal lobe epilepsy (TLE) is the most common form of focal epilepsy, affecting a significant proportion of patients who develop drug-resistant epilepsy. Surgical interventions, particularly stereoelectroencephalography (SEEG)-guided temporal lobe resection (TLR) and SEEG-guided responsive neurostimulation (RNS), have emerged as pivotal treatment options. This systematic review aims to compare the efficacy, safety, and quality of life (QoL) outcomes associated with these two interventions in adults with drug-resistant TLE.

The review followed the PRISMA 2020 guidelines, with a comprehensive literature search conducted across multiple databases from January to February 2025. Eligible studies included adult patients (≥18 years) with drug-resistant TLE who underwent SEEG-guided TLR or RNS, with preoperative SEEG used for localization. Primary outcomes included seizure freedom, seizure reduction, adverse events, and QoL improvements. Quality assessment was performed using the Cochrane Risk of Bias Tool for randomized trials and the Newcastle-Ottawa Scale for observational studies.

Fifteen studies met the inclusion criteria, encompassing sample sizes ranging from 10 to 440 participants. Key findings include:

• Seizure freedom: SEEG-guided TLR achieved an average seizure freedom rate of 58.5% (range: 32–85%), while SEEG-guided RNS resulted in 12.85% seizure freedom on average.

• Seizure reduction: TLR showed a mean seizure reduction of 75% (range: 60–90%), compared to 63.2% for RNS.

• Quality of life: QoL improvements were reported in 72–82% of TLR patients and 44% of RNS patients.

• Safety: Both interventions demonstrated strong safety profiles. TLR was associated with transient memory deficits (12%) and mild infections (8%). RNS had higher device-related issues, including lead revisions (10%) and minor infections (4%). Cognitive outcomes were better preserved with RNS.

Discussion

The review highlights that SEEG-guided TLR offers superior seizure freedom and reduction rates, making it a highly effective option for patients with well-localized epileptogenic zones. However, it carries risks of cognitive decline, particularly in dominant hemisphere resections. In contrast, RNS provides meaningful seizure reduction with cognitive preservation, making it a valuable alternative for patients with bilateral onset, eloquent cortex involvement, or prior failed resections.

The direct comparison of outcomes is limited by inherent differences in patient populations-RNS cohorts often include more complex cases. Both interventions improve QoL, but standardization of QoL assessment remains lacking. Individualized treatment planning is essential, balancing seizure control, cognitive risks, and patient-centered outcomes.

Limitations and future directions

Most included studies were observational, with only two randomized controlled trials, limiting the strength of comparative conclusions. Variability in outcome definitions and reporting also complicates synthesis. Future research should focus on:

• Standardized outcome metrics for seizure freedom and QoL.

• Long-term prospective studies on cognitive and psychiatric outcomes.

• Investigation of demographic and socio-economic factors influencing treatment response.

• Systematic reporting of device-related complications to refine clinical guidelines.

Conclusions

SEEG-guided TLR and RNS are both effective and safe interventions for drug-resistant TLE, with distinct profiles: TLR offers higher seizure freedom, while RNS preserves cognitive function. Treatment should be personalized based on patient-specific factors, including seizure localization, cognitive risks, and QoL priorities. Future studies should prioritize long-term outcomes and refined patient selection criteria to optimize epilepsy care.