Intrinsic third ventricular craniopharyngiomas: report on six cases and a review of the literature.

BACKGROUND: Craniopharyngiomas constitute 2 to 4% of intracranial neoplasms. However, the purely intraventricular variety are rare. Their magnetic resonance imaging (MRI) characteristically shows an intact third ventricular floor, a patent suprasellar cistern, an intact pituitary stalk, and the absence of sellar abnormalities.

METHODS: Between 1994 and June 2002, 6 patients with purely intraventricular craniopharyngioma were surgically managed. There were 4 cystic and 2 solid lesions. The surgical approaches utilized included a frontal, parasagittal, transcallosal approach with the third ventricle being accessed using either the transforaminal or subchoroidal approach (n = 3); pterional, transsylvian (n = 1), and bifrontal interhemispheric (n = 2) approaches in which the third ventricle was accessed via the lamina terminalis. A ventriculoperitoneal shunt was required for one of the 3 patients with hydrocephalus.

RESULTS: Total excision was performed in 3 patients with cystic craniopharyngioma, while a small residual lesion was left adherent to the third ventricular floor in the others. There was one perioperative mortality because of septicemia. Two patients required thyroxine supplementation. Two patients developed transient and one other patient a sustained diabetes insipidus. The 2 patients with solid tumors received radiotherapy for the residual lesions. At follow up ranging from 8 to 36 months, neither tumor recurrence nor regrowth was observed in any of the patients. The symptoms of raised intracranial pressure, hypothalamic dysfunction or visual field defects had resolved.

CONCLUSIONS: Intraventricular craniopharyngiomas occur in an older population and present mainly with raised intracranial pressure. Visual and endocrinologic imbalances are much less in these lesions compared to the suprasellar craniopharyngiomas. They mainly attach to the third ventricular floor. The surgical approaches to the third ventricle, along with radiotherapy and hormone supplementation, were successful in the management of these rare tumors.