Evaluation of utility of Invasive Electroencephalography for definitive surgery in patients with Drug-Resistant epilepsy: A Systematic Review and Meta-analysis

World Neurosurg. 2024 Apr 20:S1878-8750(24)00652-1. doi: 10.1016/j.wneu.2024.04.079. Online ahead of print.

Abstract

When non-invasive tests are unable to define the epileptogenic zone in patients, intracranial electroencephalography (iEEG) is a method of localising the epileptogenic zone. Compared to non-invasive evaluations, it offers more precise information about patterns of epileptiform activity, which results in useful diagnostic information that supports surgical decision-making. The primary aim of the present study was to assess the utility of iEEG for definitive surgery for patients suffering from drug-resistant epilepsy (DRE). Online databases like PubMed, Medline, Embase, Scopus, Cochrane Library, Web of Science and IEEE explorer were searched for MeSH terms and free-text keywords. ROBINS I critical appraisal tool was used for quality assessment. Prevalence from different studies was pooled together using the inverse variance heterogeneity method. Eggers regression analysis and funnel plot were used to evaluate publication bias. The systematic review included eighteen studies, while the meta-analysis included ten studies to estimate the prevalence of seizure freedom (class I Engel) in patients undergoing surgery after iEEG. There were 526 patients in all that were included in the meta-analysis. The period of follow-up ranged from one to ten years. The overall pooled estimate of the prevalence of seizure freedom (class I Engel) in patients undergoing surgery after iEEG was 53% (95% CI: 44, 62). The results additionally demonstrated that twelve studies had a moderate risk of bias, whereas six studies had a low risk. Future studies are crucial to enhance our understanding of iEEG, guiding patient choices and unraveling their implications.

Keywords: Drug-resistant epilepsy; Epilepsy surgery; Intracranial EEG; Seizure freedom.

Publication types

  • Review