[Importance of impedance audiometry on infant hearing screening test with otoacoustic emissions]

The target of this paper is to evaluate the importance of Impedanciometry in a protocol with transient evoked otoacoustic emissions on high risk infant hearing screening. We used tympanometry and stapedious reflex only when otoacoustic emissions became altered. This method try to decrease the impact in this test caused for middle ear diseases. We realized an Impedanciometry study in all children with abnormal otoacoustic responses and then, we obtained normal otoacoustic responses when tympanometry normalize. In the other hand, the time of test wasn't too large, between 15-20 minutes for child. The analysis of specificity and positive predictive value, of otoacoustic emissions without Impedanciometry was 89% and 45% respectively, however the same values with Impedanciometry was 96% and 75% respectively. In our opinion, high frequency of middle ear diseases in children, and our results, justify the introduction of Impedanciometry in a complete protocol of hearing screening with Otoacoustic Emissions, preventing appearance of false positive caused by these diseases.