Abstracts

Rationale: MRI guided strereotactic laser abalation (SLA) is now an available option to approach epileptogenic regions that were previously not easily amneable to resective epilepsy surgery. The effectiveness, risk and benefits of this procedure still need to be assesedMethods: Patients (n=5 ),with medically refractory focal epilepsy underwent stereotactic frame-based placement of MR-compatible laser catheter (1.6mm diameter) through a 3.2mm twist drill hole. An FDA-cleared laser surgery system (Visualase; Visualase/Medtronics, Inc., Houston, TX) was utilized to monitor the ablation of epileptogenic foci with real-time MRI thermometry. Temperature limits were set to protect nearby structures like the hypothalamus, basilar artery, fornices, mamillothalamic tracts as well as other structures dependent on the anatomic location of the lesionResults: All three patients with hypothalamic hamartomas became seizure free. One patient developed Panhypopituitarism, bullemia and resolving amnestic syndrome despite protection of adjacent critical structures. One patient with left occipital periventricular heteretopia had significant reduction in her seizure frequency with no complications. One patient with a frontal lesion became seizure free but had a bleed. Significant perioperative cerebral edema was noted in 2 patientsConclusions: MR Guided Stereotactic ablation is associated with seizure freedom or significant reduction in seizures in patients that were previously difficult to treat surgically. Perioperative and long term complications of this procedure should also be recognized.