temporal bone histopathologic studies found
damage in the cochlea consistent with viral injuries.
Loss of hair cells and supporting cells, atrophy of the tectorial membrane, atrophy of the stria vascularis, and neuronal loss were observed.
These patterns were similar to findings in documented cases of hearing loss secondary to mumps, measles, and maternal rubella. Viral infection can be implicated as a cause of ISSHL, but this cannot, as yet, be proven. Infections with mumps virus provide the best model for a virally induced sensorineural hearing loss. In one study of ISSHL, subclinical mumps infections were documented in 9 of 130 patients by positive immunoglobulin M (IgM) mumps antibodies.[1]