Stereoelectroencephalography-guided radiofrequency thermocoagulation of the epileptogenic zone: a potential treatment and prognostic indicator for subsequent excision surgery

Acta Neurochir (Wien). 2024 May 13;166(1):210. doi: 10.1007/s00701-024-06106-x.

Abstract

Purpose: To evaluate the safety and efficacy of stereoelectroencephalography (SEEG)-guided radiofrequency thermocoagulation (RFTC) for drug-resistant focal epilepsy and investigate the relationship between post-RFTC remission duration and delayed excision surgery effectiveness.

Methods: We conducted a retrospective analysis of 43 patients with drug-resistant focal epilepsy who underwent RFTC via SEEG electrodes. After excluding three, the remaining 40 were classified into subgroups based on procedures and outcomes. Twenty-four patients (60%) underwent a secondary excision surgery. We determined the predictive value of RFTC outcome upon subsequent surgical outcome by categorizing the delayed secondary surgery outcome as success (Engel I/II) versus failure (Engel III/IV). Demographic information, epilepsy characteristics, and the duration of seizure freedom after RFTC were assessed.

Results: Among 40 patients, 20% achieved Engel class I with RFTC alone, while 24 underwent delayed secondary excision surgery. Overall, 41.7% attained Engel class I, with a 66.7% success rate combining RFTC with delayed surgery. Seizure freedom duration was significantly longer in the success group (mean 4.9 months, SD = 2.7) versus the failure group (mean 1.9 months, SD = 1.1; P = 0.007). A higher proportion of RFTC-only and delayed surgical success group patients had preoperative lesional findings (p = 0.01), correlating with a longer time to seizure recurrence (p < 0.05). Transient postoperative complications occurred in 10%, resolving within a year.

Conclusion: This study demonstrates that SEEG-guided RFTC is a safe and potential treatment option for patients with drug-resistant focal epilepsy. A prolonged duration of seizure freedom following RFTC may serve as a predictive marker for the success of subsequent excision surgery.

Keywords: Drug-resistant focal epilepsy; Epilepsy surgery; Radiofrequency thermocoagulation; SEEG.

MeSH terms

  • Adolescent
  • Adult
  • Child
  • Drug Resistant Epilepsy* / surgery
  • Electrocoagulation* / methods
  • Electroencephalography* / methods
  • Epilepsies, Partial* / physiopathology
  • Epilepsies, Partial* / surgery
  • Female
  • Humans
  • Male
  • Middle Aged
  • Prognosis
  • Retrospective Studies
  • Stereotaxic Techniques
  • Treatment Outcome
  • Young Adult