Abstract
Facial paralysis in the newborn may be caused by trauma associated with delivery or by lesions secondary to congenital developmental anomalies. We previously reported the absence of the facial nerve in the horizontal segment of the temporal bone on both sides in a patient with Mobius' syndrome, usually classified as a nuclear developmental defect. In this study we report the findings from 7 additional temporal bones with similar abnormalities. A study of 42 temporal bones from infants with various congenital anomalies revealed nine temporal bones in which the facial nerve disappeared mid-way through the course of the temporal bone. Some of the nerve fibers suggested regeneration after necrotic lesions induced during the perinatal period.