1996 Volume 5 Issue 1 Pages 53-58
We report the case of a hypothalamic hamartoma associated with dysgenesis of the corpus callosum in a 4-year-old boy who was admitted to hospital because of gelastic seizures that had persisted for 3 years. Although a neurological examination on admission revealed no abnormal finding, his penis was large, 2.5x 6.0 cm in size. Magnetic resonance T1-weighted imaging demonstrated a mass with a relatively low intensity in the interpeduncular cistern, whereas on T2-weighted imaging this mass was depicted as being hyperintense. Additionally, this mass did not enhance on use of a contrast medium, and the corpus callosum was found to be dysgenetic. Hermonal research showed normal serum LH values, however, the FSH and testosterone values and the FSH response to an administration of LH-RH showed a pubertal pattern. Using a right peritoneal approach, samples of the patient's tissue were taken for a biopsy, and the results of a histological examination revealed nearly normal cortical tissue. However, the cytoplasms of the ganglion cells reacted positively to LH-RH immunohistochemical staining. Based on these findings the patient was diagnosed as having a hypothalamic hamartoma. Although several cases of hypothalamic hamartoma associated with other malformations, such as hydroce-phalus, porencephaly, poly-or syndactyly, and similar anomalies, have been reported, cases of a hypothalamic hamartoma associated with dysgenesis of the corpus callosum have rarely been reported. A hamartoma is thought to develop from 35 to 40 days after gestation, whereas the corpus callosum develops from the 6th to the 20th week. Based on the time disparity between the development of a hamartoma and the corpus callosum, to find an of hypothalamic hamartoma and dysgenesis of corpus callosum associationship between them at 6 weeks of gestation is indeed a rare event.
