EVOLUTION OF TRANSIENT EVOKED OTOACOUSTIC EMISSIONS IN PRETERM NEWBORNS - A PRELIMINARY-STUDY

Transient evoked otoacoustic emissions (TEOEs) were recorded in a coho rt study of preterm neonates in order to study their basic properties as a function of gestational age. Their main properties were: (1) TEOE s spectrum did not vary with age; it was analogous to those of full te rm; (2) there was no statistically significant variation of the TEOEs amplitude with age. The maturation of outer hair cell properties appea rs to be complete at a gestational age of 29 weeks. Because a number o f infants at risk for hearing loss are preterm babies, screening for T EOEs has to be performed in the neonatal care unit. To improve the acc uracy and efficiency of the test, Screening should take place as close to hospital discharge as possible, with the optimum time at 35 gestat ional weeks.