SEEG-guided radiofrequency thermocoagulation of epileptic foci in the paediatric population: Feasibility, safety and efficacy

Abstract

Focal epilepsy in children may be refractory to pharmacological treatment and surgical resection may be an appropriate option. When invasive electroencephalogram is required in the presurgical evaluation, depth electrodes can be used to create focal lesions in the epileptogenic zone using radiofrequency thermocoagulation (RFTC), to disrupt the epileptogenic zone. Methods: This study aimed to assess the efficacy and safety of RFTC in a paediatric population of 46 patients. Results: The mean age of onset was 3.3 years and the mean age at SEEG was 8.2 years. MRI lesions were identified in 71.7% of the series, among them 60% of malformation of cortical development. 43.5% of the patients were seizure free at 1 month, 26.1% were responders. The mean duration of improvement was 6.8 months. 8 children were seizure free for > 8 months and among them, 6 are currently seizure free for 8-24 months. 5 patients had functional deficits post-procedures, transient in 4 patients and prolonged in one of whom. 3/5 were anticipated following the results of cortical stimulation. Multivariate analysis found 3 independent criteria linked to RFTC efficiency one month after RFTC: frequency of the seizures before RFTC, age and number of contacts used. Conclusion: RFTC is a safe method for the paediatric population providing important predictive information for surgical resection. An improvement in seizure frequency, often transient, is seen in 2/3 of our patients. RTFC could be useful as a palliative technique for children with an epileptogenic zone overlapping with eloquent areas, with minimal risk of sequelae.

Network radiofrequency ablation for drug resistant epilepsy

“…They reported two seizure free patients, four with improvement, and three without improvement. Interestingly, the Chipaux study specifically excluded patients with a large epileptogenic zone as RFA was not expected to interrupt the diffuse epileptogenic network [10] . Conversely, our four patients were specifically selected for RFA due to a presumed large epileptogenic network we hoped to disrupt.…”

Radiofrequency Thermocoagulation in Refractory Focal Epilepsy: The Montreal Neurological Institute Experience

“…In the handful of series published on this technique, several have described subsequent resections after RF-TC with successful outcomes. 5,7,9,12,18 Early response, albeit transient, has also been suggested to hold a positive predictive value for Engel Class 1 outcome after surgical resection. 7,9 At this time, we do not feel that RF-TC is a replacement for resective surgery especially in those cases which are easily amenable to resection.…”

“…In patients with EZs in speech or motor areas who are deemed to be poor candidates for resection, RF-TC may be used as a palliative option. 18 There is little downside to performing an ablation, even in cases that are deemed appropriate for future resection, as it may impart some seizure freedom until the patient returns for the definitive operation. Even a short period of improvement in seizures may allow the patient a glimpse into a seizure-free life and provide motivation for the definitive operation.…”

“…Since the description of the first experience with SEEG-guided RF-TC by Guenot et al in 2004, a handful of series have been published with experiences from different centers in Europe and Asia. [2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19] These reports have utilized RF-TC techniques to address various pathologies causing refractory epilepsy. Given the safety profile and size of lesion created, as determined by Bourdillon et al in their in vivo and in vitro data, the SEEGguided RF-TC method may be an ideal technique for these lesions.…”

Effects of stereotactic radiofrequency thermocoagulation in the globus pallidus internus on refractory tic disorders

“…Again, some patients with TS or tic disorders were refractory to this treatment. Radiofrequency thermocoagulation has been applied clinically in the nervous system primarily for the treatment of epilepsy [35,36]. Because Kurlan et al and Sun et al had applied radiofrequency thermocoagulation in the gyri cinguli and anterior capsule interna for the treatment of TS or refractory tic disorders [5,18], we hypothesized that the use of radiofrequency thermocoagulation in the globus pallidus internus could be more effective for refractory tic disorders.…”