DRILL-INDUCED HEARING-LOSS IN THE NONOPERATED EAR

The reversible hearing loss in the nonoperated ear noted by patients a fter ear surgery remains unexplained. This study proposes that this he aring loss is caused by drill noise conducted to the nonoperated ear b y vibrations of the intact skull. This noise exposure results in dysfu nction of the outer hair cells, which may produce a temporary hearing loss. Estimations of outer hair cell function in the nonoperated ear w ere made by recording the change in amplitude of the distortion-produc t otoacoustic emissions before and during ear surgery. Reversible dril l-related outer hair cell dysfunction was seen in 2 of 12 cases. The c hanges in outer hair cell function and their clinical implications are discussed.