Distortion product otoacoustic emissions in neonates and two-month-old infants

Abstract

Evoked otoacoustic emissions have potential as a device for mass hearing screening in hospital and community health settings. Although transient evoked otoacoustic emissions have been studied extensively, there is comparatively little information on distortion product otoacoustic emission (DPOAE) in the literature. The aim of this study was to examine and compare the characteristics of DPOAEs found in neonates and two-month-old infants. Twenty fullterm neonates and 20 two-month-old infants were screened using the ILO92 Otodynamics Analyzer. The findings revealed that DPOAE amplitude was significantly higher at most test frequencies in the two-month-old infants than in the neonates. However, this was accompanied by a significant increase in noise floor for the two-month-old group. No significant differences were found in signal-to-noise ratios between the two groups. The results suggest that it may be of clinical benefit to test infants at two months of age rather than at birth provided that subject noise in the older age group can be controlled.