Hypothalamic hamartomas: Optimal approach to clinical evaluation and diagnosis

Hypothalamic hamartomas (HHs) present a difficult medical problem, manifested by gelastic seizures, which are often medically intractable. Although existing techniques offer modest surgical outcomes with the potential for significant morbidity, the relatively novel technique of magnetic resonance imaging (MRI)-guided stereotactic laser ablation (SLA) offers a potentially safer, minimally invasive method with high efficacy for the HH treatment. We report here on 14 patients with medically refractory gelastic epilepsy who underwent stereotactic frame-based placement of an MR-compatible laser catheter (1.6mm diameter) through a 3.2-mm twist drill hole. A U.S. Food and Drug Administration (FDA)-cleared laser surgery system (Visualase, Inc.) was utilized to ablate the HH, using real-time MRI thermometry. Seizure freedom was obtained in 12 (86%) of 14 cases, with mean follow-up of 9months. There were no permanent surgical complications, neurologic deficits, or neuroendocrine disturbances. One patient had a minor subarachnoid hemorrhage that was asymptomatic. Most patients were discharged home within 1day. SLA was demonstrated to be a safe and effective minimally invasive tool in the ablation of epileptogenic HH. Because use of SLA for HH is being adopted by other medical centers, further data will be acquired to help treat this difficult disorder.