Imaging Characteristics of Hypothalamic Hamartomas in an Australian Paediatric Population

Background Hypothalamic hamartoma (HH) is a rare congenital malformation that can significantly disrupt patient quality of life and typically presents with either central precocious puberty or gelastic seizures. Objective We seek to add to the current literature through a retrospective review of all cases of HH seen at our paediatric tertiary centre over the previous two decades. We also sought to test the novel hypothesis that lesions located closer to or contacting the infundibulum were more likely to present with central precocious puberty (CPP). Materials and Methods Retrospective review of the public PACS system was performed, yielding a total of sixteen patients with HH identified on MRI between January 2000 and February 2022. Imaging and patient records were retrospectively evaluated. Results Six patients presented with central precocious puberty (CPP), six with gelastic or other seizure disorders, and four had alternate presenting issues. Our study demonstrates a statistically significant relationship between pedunculated lesions and CPP and between sessile/intrahypothalamic lesions and gelastic seizure/neuropsychiatric symptoms. We did not demonstrate a relationship between tumour location relative to the infundibulum or mammillary bodies and clinical manifestations. Conclusion Hypothalamic hamartomas are rare congenital malformations which typically present with one of two classical phenotypes: CPP or gelastic seizure. The study demonstrates a statistically significant relationship between pedunculated lesions and CPP and between lesions with third ventricular involvement and gelastic seizure/neuropsychiatric symptoms. We did not demonstrate a clear relationship between specific tumour location within the hypothalamus and phenotype; larger cohort studies are recommended to further investigate this hypothesis.