title: Few isolated neurons in hypothalamic hamartomas may cause gelastic seizures.
abstract: Hypothalamic hamartomas (HHs) are congenital, benign masses in the hypothalamus and tuber cinereum that may cause central precocious puberty and gelastic seizures. Nodules of small neurons are thought to be a universal feature of the microarchitecture of HH lesions associated with epilepsy. Here we describe the case of a 5-year-old boy with gelastic seizures who underwent resection of a HH that contained nodules of glial cells, but only few, randomly distributed neurons. HHs that contain few or no neurons have only been reported thus far in cases associated with precocious puberty. This case demonstrates that few solitary neurons in HHs can drive the development of gelastic seizures, and nodules of small neurons may not be a universal feature of HHs associated with epilepsy. This finding is clinically important since hypothalamic hamartomas with rare neurons can easily be misdiagnosed as pilocytic astrocytomas or subependymomas if their presence is overlooked. A neuronal stain is helpful in making the correct diagnosis in these cases.
authors.affiliation: Department of Surgery, Division of Neurosurgery, Duke University Medical Center, Durham, N.C., USA.
authors.forename: Ben
authors.initials: B
authors.lastname: Waldau
authors.forename: Roger E
authors.initials: RE
authors.lastname: McLendon
authors.forename: Herbert E
authors.initials: HE
authors.lastname: Fuchs
authors.forename: Timothy M
authors.initials: TM
authors.lastname: George
authors.forename: Gerald A
authors.initials: GA
authors.lastname: Grant
mesh_terms: D001706:Biopsy; D002675:Child, Preschool; D004828:Epilepsies, Partial / Q000209:etiology* / Q000473:pathology*; D006222:Hamartoma / Q000150:complications* / Q000473:pathology*; D006801:Humans; D007027:Hypothalamic Diseases / Q000150:complications* / Q000473:pathology*; D007031:Hypothalamus / Q000473:pathology; D008279:Magnetic Resonance Imaging; D008297:Male; D009474:Neurons / Q000473:pathology