Computerized cranial tomography of free intracranial fat in congenital tumors

Three additional cases of free intracranial fat associated with congenital tumors are reported. The migration of fat with positional change is detailed. Free intraventricular fat may present without transcerebral rupture of the tumor. Our experience with these three patients, plus the two previously reported, suggest that two conditions must be present for oily material to enter the ventricular system through the outlets of the fourth ventricle: first, there must be a reversal of bulk flow of cerebrospinal fluid; second, the oily material must have a specific gravity less than that of cerebrospinal fluid. Also noted from our series is the absence of serious clinical sequelae associated with rupture or leakage of fatty tumors.