Neuroepithelial cysts of the middle ear.

Neuroepithelial cysts are lesions of the central nervous system that have previously been reported in cerebral parenchyma, in the spinal cord, and within the ventricles in association with the choroid plexus. We describe 2 cases of neuroepithelial cysts of the middle ear. One was diagnosed after surgery for a retraction pocket and chronic otitis media complicated by an intraoperative cerebrospinal fluid (CSF) leak. The other produced bilateral spontaneous CSF otorrhea and mimicked the presentation of arachnoid granulations. Both cases were verified with immunohistochemical stains. Neuroepithelial cysts, although rare, should be considered in the differential diagnosis of spontaneous CSF otorrhea or an epitympanic mass.