OBJECTIVE: 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.
METHODS: 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.
RESULTS: 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.
CONCLUSION: 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.
