Pathology of deafness and disequilibrium in head injury:a human temporal bone study

A Caucasian male suffered a skull fracture at age twenty-two. There was bilateral deafness with partial recovery of hearing in the left ear. He was able successfully to wear a hearing aid in this ear for only thirteen years. His balance remained impaired until death at age fifty of unrelated causes. Temporal bone histologic studies revealed bilateral transverse fractures extending through the ampullated end of the three semicircular canals and vestibula. The cochleae were not involved. In the right ear, the organ of Corti was missing in the basal 14 mm and shrunken in the remainder of the cochlea. In the left ear, the organ of Corti was missing in the basal 14 mm and present with partial hair cell loss in the remainder of the cochlea. Spiral ganglion neuron loss correlated in severity with the organ of Corti lesions bilaterally. The membranous vestibular labyrinth showed distension and ruptures with total loss of sensory epithelium of the cristae and maculae bilaterally. Progressive deterioration of left ear residual hearing cannot be explained on the basis of sensorineural deficit; it probably was the result of biochemical alterations. Total loss of vestibular sensory epithelium bilaterally explained the persistent disequilibrium.