Optimized SEEG-guided radiofrequency thermocoagulation in the treatment of pediatric hypothalamic hamartomas

Purpose: This study investigated the role of one-stage stereo-array radiofrequency thermocoagulation based on stereotactic electroencephalography in the treatment of pediatric hypothalamic hamartomas.

Methods: We analyzed the clinical data of 28 patients with hypothalamic hamartoma. A high-density focal stereo-array electrode implantation strategy was adopted. Stereotactic electroencephalography guided bipolar coagulations were performed between two contiguous contacts of the same electrode, or between two adjacent contacts of different electrodes. Patients with hypothalamic hamartoma were divided into two groups based on hamartoma size (maximum diameter < 15 mm vs maximum diameter ≥ 15 mm). Numbers of implanted electrodes and contacts used for thermocoagulation were documented. Seizure outcome was evaluated according to Engel's classification.

Results: Surgical procedures were well tolerated and no repeated surgery was performed. The median number of electrodes implanted in the two groups was significantly different (p = 0.0009), as well as the median number of contacts where radiofrequency thermocoagulation was applied (p = 0.0006). Moreover, the number of implanted electrodes and contacts used for thermocoagulation were positively correlated with the hamartoma volume (Spearman's rho = 0.7074, p＜0.0001 and Spearman's rho = 0.7435, p＜0.0001, respectively). The overall seizure-free rate was 82.1 %, with 92.9 % of the patients having favorable outcomes for at least 12 months of follow-up. Seizure outcomes between two groups were not statistically significant (p = 0.3138).

Conclusion: One-stage high-density focal stereo-array stereotactic electroencephalography guided radiofrequency thermocoagulation using cross-bonded electrode contacts for ablation range expansion is a safe and effective surgical approach for children with hypothalamic hamartoma.