Pathology of Méniére's disease. Further studies.

Abstract

Temporal bone findings are described in a 66-year-old white man with a one and one-half year history of Meniere's syndrome. Unilateral advanced endolymphatic hydrops of the cochlea and saccule, and numerous outpouchings of the utricle and semicircular ampullae were present. There was displacement of the utricle into the perilymphatic space of all the ampullae, as well as retrograde endolymphatic hydrops of most of the crus commune. The endolymphatic duct and intermediate portion of the endolymphatic sac demonstrated a rather straight course to the posterior fossa, with virtually no lateral curving. This same finding, however, was present in the opposite side where there was no evidence of endolymphatic hydrops. The cochlea, on the involved side, demonstrated considerable decrease in spiral ganglion cells and outer and inner hair cells throughout, most severe in the beginning of the basal turn. Degenerative changes were present in all the vestibular sensory receptor areas. Incidental histological otosclerosis of the oval window was found bilaterally. An unusual finding was bilateral focal nodular hyperplasia of the Schwann cells of the facial nerve within the internal auditory canal, with no compression of adjacent nerve trunks. This condition is rare and may simulate true tumors. The etiology here was unassociated with any other neurological disorder and is unexplained.