Cochlear changes after herpes simplex virus infection.

After direct inoculation of herpes simplex virus (HSV) into the scala tympani of the guinea pig, the tectorial membrane showed various morphological changes: atrophy, roll-up and dot formation. Immunofluorescent and electronmicroscopic studies revealed that the changes were due to HSV infection. The findings were compared with those observed in the temporal bones of a 77-year-old patient who suffered from sudden deafness. The tectorial membranes of both temporal bones showed various changes identical with those observed in experimental viral labyrinthitis. This supports the view that sudden deafness in this particular patient was of viral origin. In the animal experiment, HSV antigen could be detected from the cochlea of the non-inoculated side, which was morphologically normal. Further study is required to reactivate HSV in the cochlea with latent infection. This animal can probably be used as an animal model for sudden deafness.