Severe middle ear anomaly with underdeveloped facial nerve. A temporal bone histopathologic case report.

The temporal bone histopathologic condition of a 9-year-old patient with unilateral congenital facial palsy and an auricular anomaly is described. The major pathologic findings were an extremely underdeveloped facial nerve, abnormal course of the facial nerve, an abnormally large middle ear artery that was suspected to be a persistent stapedial artery, absence of a pneumatized tympanic cavity, a severe ossicular anomaly, and an enlarged Eustachian tube. We believe that this child had a severe type of developmental anomaly of the middle ear, possibly caused by changes that occurred in early embryonal life. We reviewed the literature for similar cases in which the facial nerve is anomalous. We present a classification of such anomalies in the temporal bone in this case and in eight others and discuss the clinical implications of such anomalies.