Latency of distortion product otoacoustic emissions (DPOE) is defined as the time that the acoustic stimulus takes to reach the site generating the otoacoustic emission, inside de cochlea, and the return to the external acoustic meatus, to be register. DPOE latency may serve as a useful tool to study cochlear maturational changes as well as the micromechanics of the cochlea, since a relationship between DPE latency and the cochlear traveling wave was observed. Studies on adults showed a decrease in the latency with an increase of the sound frequency, varying from 13.8 ms in 787 hz to 4.4 ms in 5 kz. This decrease occurs due to tonotopic arrangement of the cochlea. Studies on this area are rare in the literature and no criteria of normality are found for these measurements, mainly in newborns. AIM: Thus, the main of this study was to characterize the latency measurements of the DPOE in full-term newborns without any hearing risk. STUDY DESIGN: Control study. MATERIAL AND METHOD: Thirty-one full term newborns of both sexes were evaluated. The procedure used was the "latencygram" program. The tested frequencies were 3 to 6 kHz at the intensity of 70 dBNA for f1 and f2. RESULTS: The obtained results showed a decrease in the latency with the increase in the sound frequency and a difference between sexes was also observed.
latency; otoacoustic emissions; newborns
