Gamma-Knife Radiosurgery for Hypothalamic Hamartoma-Related Epilepsy

Abstract

Purpose Hypothalamic hamartoma (HH), a rare congenital disorder, can cause intractable epilepsy and requires optimal surgical treatment. This study analyzed the clinical characteristics of HH and evaluated seizure outcomes and the safety of gamma-knife radiosurgery (GKS) in HH-related epilepsy to propose an optimal surgical treatment. Methods We reviewed the medical records of 18 patients with HH treated at Samsung Medical Center (1997 to 2018), and analyzed their presenting symptoms, brain magnetic resonance imaging (MRI) findings, treatment, and response. Results The median diagnostic age was 3.2 years. The first presenting symptom was a seizure in six (33.3%), precocious puberty in five (27.8%), both symptoms in six (33.3%), and no symptoms in one patient who was diagnosed incidentally on brain MRI. All mixed and intrahypothalamic types except one had seizures (n=12), while all five parahypothalamic types presented only precocious puberty. Eleven patients showed intractable epilepsy with medications and underwent surgical treatment (most commonly GKS). Eight patients underwent GKS, and two of them received repeated GKS for recurrent seizures. Six patients showed improved seizure control with GKS as the last treatment. Among them, two patients became seizure-free, and one patient had a decreased frequency of seizures after a single GKS. There was no adverse effect related to GKS. Conclusion Intractable epilepsy was the most common indication for surgical treatment of pediatric HH. GKS was effective in controlling seizures in 75% of HH patients without any adverse effects. Repeated GKS could also be considered as a safe option for intractable and disabling seizures.

Keywords

• radiosurgery
• hypothalamic hamartomas
• drug resistant epilepsy
• puberty, precocious