Accuracy of distortion-product otoacoustic emissions-based ototoxicity monitoring using various primary frequency step-sizes.

OBJECTIVE A cisplatin ototoxicity monitoring protocol was recently proposed using distortion-product otoacoustic emissions (DPOAEs) measured in 1/48th octave steps over the highest obtainable quarter octave ( Dille et al, 2010 ). This protocol can take up to 40 minutes to complete in both ears among seriously ill patients in a potentially noisy test environment. The goal of the current study was to contrast the diagnostic accuracy of ototoxicity monitoring protocols based on changes in DPOAE levels at wider, more rapidly tested, primary frequency step sizes. DESIGN Measure DPOAE levels in 1/48th octave steps over the highest half-octave of obtainable DPOAEs prior to treatment and at each ototoxicity monitoring session during the course of treatment with cisplatin. STUDY SAMPLE Nineteen cancer patients being treated with cisplatin at the Portland Veterans Affairs Medical Center were observed over 56 monitoring appointments. Hearing thresholds in the sensitive region for ototoxicity (SRO) were measured concurrently with DPOAE levels. RESULTS DPOAE levels measured in 1/24th octave steps provided comparable accuracy, and half the testing time, to the 1/48th octave step protocol previously described. CONCLUSIONS DPOAE level shifts measured in 1/24th octave steps may provide a basis for rapid ototoxicity monitoring among adult cancer patients treated with cisplatin.