[Diagnosis and operative sequela of rare abnormalities of the inner ear].

Two cases of congenital unilateral deafness in otherwise normal children are presented. X-ray examination showed a partition of the inner ear canal in one of them. A review of the literature showed this lesion to be very rare, but it is more frequent in combination with other malformations such as the Klippel-Feil-syndrome, Wildervanck-syndrome and Thalidomide embryopathy. The second child showed an extensive malformation of the cochlear and vestibular parts of the inner ear and of the internal auditory meatus. The vestibulocochlear nerve was absent. An arachnoidal cyst protruding into the tympanic cavity formed the only boundary between the middle ear and the cerebrospinal fluid. This resulted in relapsing meningitis and a postmeningitic hearing loss on the other side. A tympanoscopy and closure of the connection between the tympanic cavity and the internal auditory meatus stopped the ascending infections.