Epilepsy Surgery — SEEG and Laser Ablation

Drug-resistant focal epilepsy affects up to one-third of patients and warrants evaluation in a comprehensive epilepsy center. Stereo-electroencephalography (SEEG) is a minimally invasive intracranial monitoring technique that uses depth electrodes implanted via robotic stereotactic guidance to record from cortical and deep structures, identifying the seizure onset zone and irritative network in three dimensions.

MRI-guided laser interstitial thermal therapy (LITT) delivers targeted thermal ablation through a 3.2 mm catheter with real-time MR thermography monitoring. It is increasingly used for mesial temporal lobe epilepsy with hippocampal sclerosis, hypothalamic hamartoma, focal cortical dysplasia, and periventricular nodular heterotopia, offering shorter hospitalization (typically 1-2 days), faster return to work, and reduced neuropsychological deficits compared with open resection.

Patient selection involves multidisciplinary review with high-resolution MRI, FDG-PET, video-EEG, neuropsychology, and functional MRI. Outcomes show 50-65 percent seizure freedom for mesial temporal cases, similar to open anterior temporal lobectomy, with better verbal memory preservation. Risks include intracranial hemorrhage (1-2 percent), visual field defects, and incomplete ablation requiring re-treatment.