QUANTITATIVE ASSESSMENT OF METHODS FOR THE DETECTION OF OTOACOUSTIC EMISSIONS

Objective: To compare the performance of various types of signal detec tor commonly used to detect otoacoustic emissions (OAEs). Method: The signal detectors were tested with signals in various types of noise, i ncluding noise with various amplitude distributions. Commonly utilized transient evoked OAE and distortion product OAE detectors were analyz ed. Results: In both cases it was found that detector performance incr eased as the measurement bandwidth was increased. Noises of different amplitude distributions were found to affect the performance of both t ypes of detectors. The effect of different amplitude distributions dec reased as the measurement bandwidth was increased. For a given power p er spectral line, the transient evoked OAE detector could detect signa ls 6 dB farther into gaussian noise than the distortion product OAE de tector. Conclusions: An analysis of the results of practical methods o f OAE measurement show that distortion product OAEs can be measured wi th higher power per spectral line than transient evoked OAEs. This mea ns that in adult humans distortion product OAEs can be reliably detect ed in about 1/14th of the time of transient evoked OAEs. In neonatal h umans distortion product OAEs can be reliably detected in about two-th irds of the time of transient evoked 0AEs.