Abstracts

Rationale: To investigate the tolerability, efficacy, outcomes of refractory generalized epilepsy, gelastic seizures, ADHD and neurocognitive comorbidities in patients with hypothalamic hamartomas treated with minimally invasive lesionectomy employing laser-induced thermal ablation technology. Hypothalamic hamartomas are rare developmental lesions associated with gelastic epilepsy, generalized epilepsy and simple partial epilepsy, cognitive decline, neurocognitive difficulties, and/or precocious puberty. Seizures are refractory to anticonvulsants, often necessitating different surgical options. Recent application of a minimally invasive laser-induced thermal ablation technology reveals compelling evidence for better tolerability and diminished morbidity with good efficacy and favorable outcomes. Methods: A 3-year-old boy, diagnosed with precocious puberty at 10 months of age in the setting of a type III hypothalamic hamartoma, with a right 1-mm pedunculated and a left 4-mm sessile attachment to the floor of the third ventricle, developed seizures characterized by hand shaking, blank stares lasting up to a minute, tonic seizures and head drops happening daily. Video EEG monitoring showed multiple events with sudden onset of bilateral tonic arm elevation, head drop and gelastic seizures, associated with rhythmic bi-frontal, temporal spike waves. Despite maximum doses of levetiracetam and clobazam, neither seizure frequency, nor behavioral issues (temper tantrums, self-aggression, hyperactivity) improved. Hence surgical options were presented to the family, who opted for the MRI-guided laser thermal ablation of the tumor. Informed consent was obtained as per our approved institutional IRB for MRI-guided laser ablation procedures for patients with epilepsy.Results: The procedure was performed under general anesthesia, with a trajectory to disconnect the hamartoma through the 4-mm sessile attachment. The patient tolerated the procedure well. He was discharged home in stable condition on post-operative day 1. At the 2-week post-procedure assessment, the family reported significant improvement on behavior. At 6-month post-procedure, despite no change in his anticonvulsant regimen, the patient remains seizure-free, with constantly improving behavioral difficulties and personal social skills. The precocious puberty has resolved six months after the procedure. Conclusions: MRI-guided laser-induced thermal ablation is a minimally invasive technology with potential new applications. Initially used for brain tumors, its incipient use for a variety of epileptogenic foci (hypothalamic hamartomas, cortical dysplasias, tuberous-sclerosis complex) or as a disconnection tool that allows new treatment option for patients with refractory epilepsy without potential complications and morbidities of conventional neurosurgery. Although the acute and mid-term results are promising, systematic analysis of long-term outcomes needs to be properly collected and analyzed.