[Middle ear abnormalities in Klippel-Feil syndrome].

Klippel-Feil syndrome is characterized by a short-neck and a low occipital hairline due to such deformaties of the cervical spine as aplasia, dysplasia and fusions of the cervical and thoracic vertebrae. Approximately 1/3 of cases have sensorineural deafness, although occasional unilateral or bilateral conductive hearing loss due to middle ear malformations have been described. We have now treated two cases with unilateral middle ear malformations in patients with known Klippel-Feil syndrome. In the first case a completely malformed stapes was found as well as an atypical course of the facial nerve, which was found to be exactly over an absent oval window. In the second case aplasia of the stapes was seen and the oval and round windows were absent. No epitympanum was identifiable and a compact mastoid was found. In addition to audiometry, high-resolution CT was indispensable in diagnosis. However, surgical procedures in cases with unilateral middle ear deformations should be performed only on explicit request of the patient and not before the age of 16.