Ictal laughter associated with paroxysmal hypothalamopituitary dysfunction

Purpose: Seizures with ictal laughter (also termed gelastic seizures) have been associated with hypothalamic hamartomas and precocious puberty. It is not known, however, where in the brain such seizures originate. We describe a child with gelastic seizures and a hypothalamic lesion (probably a hamartoma) in whom two dysfunctional phenomena were observed. Results: First, there was a hyperperfusion in the hypothalamopituitary areas shown by ictal [(99m)]Te hexamethylpropyleneamine oxime (HM-PAO) single photon-emission computed tomography (SPECT). Second, there was an ictal pulse of gonadotropins, 17 beta-estradiol, and growth hormone well above the normal limits in one of the seizures. Conclusion: These findings suggest that gelastic seizures associated with hypothalamic hamartomas are generated in the hypothalamus or in its neighboring regions and that these seizures may cause paroxysmal dysfunction of the hypothalamopitutary axis.