Third ventricular schwannoma with hydrocephalus.

Intraventricular schwannomas are rare, with only 20 cases reported in the literature to our knowledge, including two cases of schwannomas in the third ventricle. We report a 23-year-old man with a mass in the posterior portion of the third ventricle and obstructive hydrocephalus. The intraventricular mass was clearly visualized and removed by neuroendoscopic surgery, and endoscopic third ventriculostomy was simultaneously performed for the hydrocephalus. Histological and immunohistochemical assays of the surgical sample established a diagnosis of intraventricular schwannoma. The patient had a favourable outcome and no neurological deficits 1 year later. The schwannoma was distant from the choroid plexus, which supports the hypothesis that the schwannoma originated from ectopic neural crest cells that were displaced during embryogenesis.