[Fatal intracranial increase in pressure caused by a colloid cyst of the 3d ventricle not diagnosed intra vitam].

The case is reported of a 26 year-old man with a colloid cyst of the third ventricle (paraphyseal cyst; neuroepithelial cyst), which gave rise to a fatal increase in intracranial pressure. Despite repeated hospitalisation the diagnosis was not established prior to death. This report serves as a reminder that this rare disorder must be considered in the differential diagnosis of conditions causing increased intracranial pressure in view of the life-saving therapeutic management required to avert a fatal outcome.