Objective Measures of Ototoxicity

A leading cause of preventable sensorineural hearing loss is therapeutic treatment with medications that are toxic to inner ear tissues, including certain drugs used to fight cancer and life-threatening infectious diseases. Ototoxic-induced hearing loss typically begins in the high frequencies and progresses to lower frequencies as drug administration continues (Campbell & Durrant, 1993; Campbell et al., 2003; Macdonald, Harrison, Wake, Bliss, & Macdonald, 1994). It is important to detect ototoxicity before damage occurs to the region of hearing < 4 kHz, which is important for speech perception (De Paolis, Janota, & Frank, 1996). Sensitive and time-efficient behavioral techniques have been developed to monitor high-frequency (> 8 kHz) hearing to detect ototoxic-induced changes before damage has progressed to lower frequencies (Fausti et al., 1999). Hearing thresholds obtained through behavioral audiometry are the current gold standard for detecting ototoxic-induced changes in hearing. However, behavioral techniques are not effective for a large population of patients who are unable to provide reliable responses; subsequently, many of these patients do not receive monitoring for ototoxic-induced changes in their hearing. The development of objective measures that do not require patient cooperation is necessary to monitor all patients receiving ototoxic drugs.