Reversible cisplatin ototoxicity in the albino guinea pig.

Guinea pigs implanted with round window electrodes received daily doses (2.0 mg/kg) of cisplatin until a profound hearing loss occurred (> 40 dB at 8 kHz). Afterwards, pronounced recovery occurred. Recovery progressed over intervals up to 3 weeks before it saturated. Loss and recovery involved both the compound action potential and, less pronounced, the cochlear microphonics. Cochlear potentials evoked by lower frequencies recovered more fully than those evoked by higher frequencies. Loss and recovery was found also in the endocochlear potential. Outer hair cell counts did not change over the recovery period. These findings confirm our previously reported results on the reversibility of cisplatin damage. Further, they implicate the vascular stria as an important target for cisplatin in the cochlea.