Tinnitus and 2f1-f2 distortion product otoacoustic emissions following salicylate overdose.

A 22-year-old woman consumed approximately 10 g of salicylate with suicidal intent. She had a severe hearing loss and a strong tinnitus within 22 h of the overdose, and then 24 h later a subsequent hearing restoration and tinnitus abolishment. Transiently evoked otoacoustic emissions (TEOAEs) and 2f1−f2 distortion product otoacoustic emissions (DPOAEs) were measured in both states. In the state of intoxication DPOAEs could be recorded well in the frequency range that corresponded to the appearance of the tinnitus despite the 50-dB hearing loss. The corresponding DPOAE I/O-functions were linearized, indicating loss of outer hair cell compression. After recovery, DPOAE level and DPOAE growth were within the normal range and showed normal physiological compression. The TEOAEs were missing in the acute state of intoxication. This case supports the hypothesis that aspirin-induced tinnitus is generated at the outer hair cell level. Whereas TEOAEs only give evidence that something might have changed in the cochl...