Conclusion: Middle and inner ear interactions in otitis media can lead to cochlear pathology. More severe pathological changes observed in the basal turn of the cochlea are consistent with prevalence of sensorineural hearing loss at higher frequencies in patients with otitis media.
Methods: Of 614 temporal bones with otitis media, 47 with chronic and 35 with purulent otitis media were selected following strict exclusion of subjects with a history of acoustic trauma, head trauma, ototoxic drugs, and other diseases affecting the cochlear labyrinth. Temporal bones with labyrinthine inflammatory changes were further evaluated for loss of hair cells and other histopathologic changes compared to age-matched controls.
Results: In all, 19% of temporal bones with chronic and 9% with purulent otitis media showed labyrinthine inflammatory changes. In chronic otitis media, inflammatory changes were: 56% localized purulent, 22% localized serous, 11% generalized seropurulent, and 11% generalized serous. Inflammatory changes in temporal bones with purulent otitis media included 67% localized purulent and 33% were generalized seropurulent. Pathological findings included: serofibrinous precipitates and inflammatory cells in scala tympani of basal turn and cochlear aqueduct, significant loss of outer and inner hair cells, and significant decrease in area of stria vascularis in the basal turn of the cochlea, as compared to controls.