Abstracts

Rationale: Stereotactic laser ablation (SLA) has broad applications in the management of intracranial pathology. We describe a novel surgical approach using robot-assisted SLA as an accurate and minimally invasive method of safely ablating non-lesional epileptic foci in the management of medically intractable epilepsy.Methods: After stereoelectroencephalography (SEEG) mapping for seizure localization, epileptic network nodes were targeted using laser technology under robotic guidance in 4 patients with non-lesional medically intractable epilepsy and “difficult to localize” seizures. The laser applicators (1.65 mm diameter) positions were confirmed under intraoperative MRI (IMRIS, Inc.). Multi-planar and real-time thermal images were performed with treatment estimates in each plane. Immediate post-ablation confirmation was done using a T1 MRI post-gadolinium contrasted series. Demographics, seizure outcome and complications were analyzedResults: MRI confirmed accurate placement of the ablation catheter along the preplanned trajectory with the applicator advanced to the gray-white matter boundary of the targeted foci. Epileptic networks involving the orbitofrontal, insular and perisylvian cortical areas were targeted. Overall operative time was approximately 2.5 to 3 hours. Patients were discharged in less than 24 hours. No complications were noted. All patients had seizure frequency and severity improved after the surgical treatment. The mean follow up was 6 months.Conclusions: The SEEG guided laser ablation method, although tested in a small group of patients, demonstrated promising results. The proposed method correspond to a minimally invasive treatment alternative for patients with medically refractory epilepsy with “difficult to localize” seizures.