Systematic Review and Meta-Analysis of Responsive Neurostimulation in Epilepsy

Dorian M Kusyk; Justin Meinert; Kristen Camille Stabingas; Yue Yin; Alexander C Whiting

doi:10.1016/j.wneu.2022.07.147

Systematic Review and Meta-Analysis of Responsive Neurostimulation in Epilepsy

World Neurosurg. 2022 Nov:167:e70-e78. doi: 10.1016/j.wneu.2022.07.147. Epub 2022 Aug 7.

Authors

Dorian M Kusyk¹, Justin Meinert², Kristen Camille Stabingas¹, Yue Yin³, Alexander C Whiting⁴

Affiliations

¹ Department of Neurosurgery, Allegheny Health Network, Pittsburgh, Pennsylvania, USA.
² College of Medicine, Drexel University, Philadelphia, Pennsylvania, USA.
³ Allegheny-Singer Research Institute, Allegheny Health Network, Pittsburgh, Pennsylvania, USA.
⁴ Department of Neurosurgery, Allegheny Health Network, Pittsburgh, Pennsylvania, USA. Electronic address: Alexander.whiting@ahn.org.

PMID: 35948217
DOI: 10.1016/j.wneu.2022.07.147

Abstract

Background: Neuromodulatory implants provide promising alternatives for patients with drug-resistant epilepsy (DRE) in whom resective or ablative surgery is not an option. Responsive neurostimulation (RNS) operates a unique "closed-loop" system of electrocorticography-triggered stimulation for seizure control. A comprehensive review of the current literature would be valuable to guide clinical decision-making regarding RNS.

Methods: Following Preferred Reporting Items for Systematic Reviews and Meta-Analyses protocols, a systematic PubMed literature review was performed to identify appropriate studies involving patients undergoing RNS for DRE. Full texts of included studies were analyzed and extracted data regarding demographics, seizure reduction rate, responder rate (defined as patients with >50% seizure reduction), and complications were compiled for comprehensive statistical analysis.

Results: A total of 313 studies were screened, and 17 studies were included in the final review, representative of 541 patients. Mean seizure reduction rate was 68% (95% confidence interval 61%-76%), and the mean responder rate was 68% (95% confidence interval 60%-75%). Complications occurred in 102 of 541 patients, for a complication rate of 18.9%. A strong publication bias toward greater seizure reduction rate and increased responder rate was demonstrated among included literature.

Conclusions: A meta-analysis of recent RNS for DRE literature demonstrates seizure reduction and responder rates comparable with other neuromodulatory implants for epilepsy, demonstrating both the value of this intervention and the need for further research to delineate the optimal patient populations. This analysis also demonstrates a strong publication bias toward positive primary outcomes, highlighting the limitations of current literature. Currently, RNS data are optimistic for the treatment of DRE but should be interpreted cautiously.

Keywords: Epilepsy; Meta-analysis; Neuromodulation; Responsive neurostimulation.

Publication types

Meta-Analysis
Systematic Review

MeSH terms

Deep Brain Stimulation* / methods
Drug Resistant Epilepsy* / surgery
Epilepsy* / therapy
Humans
Seizures
Treatment Outcome