Hypothalamic hamartomas--clinical, neuropathological and surgical aspects.

INTRODUCTION: Hypothalamic hamartomas are rare congenital lesions of the tuber cinereum presenting with the classic triad of gelastic epilepsy, central precocious puberty and developmental delay. The clinical course in the majority is one of progression, commencing with gelastic seizures in infancy, deteriorating into more complex seizure disorders and resulting in a catastrophic epilepsy associated with a concomitant cognitive and behavioural decline. OBSERVATION: Electrophysiological, radiological and pathophysiological studies have confirmed the intrinsic epileptogenicity of the hypothalamic hamartoma. Secondary generalised epilepsy seen in this condition is theorised to be through propagation via the mamillothalamic pathways with attachment to the mamillary bodies identified on MRI. Indications as to timing for surgery remain ill-defined although there is a theoretical argument to intervene before the development of secondary generalised epilepsy. SURGICAL APPROACH: Currently, the most effective surgical route appears to be the transcallosal anterior interforniceal approach although newer approaches of endoscopic disconnection and radiosurgery are being assessed.