title: [Facial nerve abnormalities in malformed temporal bone].
abstract: Between 1987 and 1993, 4500 tympanoplasties and stapedectomies were performed at the ENT Department of the University of Würzburg. In 134 cases, surgery was performed for malformation of the middle ear. The surgery reports of these patients were analyzed for anomalies of the facial nerve. Forty cases (29.9%) showed an anomaly of the facial nerve, more often congenital aural atresia or major malformation (30.4%) than minor malformation (29.1%). The most frequent finding was a dislocation of the nerve over the oval niche and resulting narrowing of the oval window (22 cases). Eleven cases showed the facial nerve without bony covers, in two cases there was an exposed nerve over the oval niche. An acute-angled course between horizontal and vertical segment in the mastoid, doubling of the nerve, lateralization of the mastoidal segment, and anterior shift of the Fallopian canal in the mastoid were observed once. To reduce the risk of facial nerve injury, high resolution CT scan studies should be performed before surgery in the presence of congenital aural atresia.
mesh_terms: D003937:Diagnosis, Differential; D004432:Ear, Middle / Q000002:abnormalities* / Q000601:surgery; D005154:Facial Nerve / Q000002:abnormalities* / Q000601:surgery; D006801:Humans; D013201:Stapes Surgery; D014057:Tomography, X-Ray Computed; D014433:Tympanoplasty
vernacular_title: Anomalien des Nervus facialis im fehlgebildeten Felsenbein.