Ototoxicity from organic solvents assessed by an inner ear test battery

This study adopted an inner ear test battery comprising audiometry, and ocular vestibular-evoked myogenic potential (oVEMP), cervical VEMP (cVEMP) and caloric tests to assess inner ear function in patients with long term exposure to organic solvents.

Eighteen patients exposed to organic solvents and another 18 non-exposed controls from the same environment were enrolled in this study. Each subject underwent an inner ear test battery.

The percentages of abnormalities identified by the oVEMP test, cVEMP test, audiometry and caloric test for the exposed group were 85%, 54%, 50% and 33%, respectively, which showed significant differences when compared with the respective 8%, 8%, 6% and 0 for the non-exposed group. Additionally, a significantly declining trend of inner ear deficits from the utricle to the saccule, cochlea, and semicircular canals was noted in the exposed group, but not in the non-exposed group.

Ototoxicity was identified in those exposed to organic solvents, with the sequence of abnormal inner ear function from the utricle to the saccule, cochlea, and semicircular canals.