[Acoustic distortion products otoacoustic emissions (DPOAE) in neonatal screening]. / L'impiego delle DPOAE negli screenings neonatali.

The purpose of the work was to determine the feasibility of direct nursery DPOAE testing in a universal hearing screening, evaluate the results and calculate the reliability of this test vs. Auditory Brainstem Responses (ABR). To this purpose DPOAE (sweep and I/O test) were performed on 500 children born between January and August 1996 at the Civil Hospital of Mestre, Italy. All the children were examined in the nursery, no matter what the risk factors or specific motivations. Besides determining whether the examination could be performed, its specificity and sensitivity, the time required and any variation depending on the day of testing were also evaluated. In a high percentage of cases (11.2%) it proved impossible to perform the test. In addition, when compared to ABR, the percentage of false positives was rather high (16.2%) and specificity was 84%. As conceived, the test requires 6'09" per ear. Comparison of the differences in results according to day of execution did not appear significant although there was a lower percentage of false positive after the third day of life. DPOAE can be measured in the nursery. The high number of false positives and the frequent need to repeat the measurements, however, increase the amount of time required for this test, thus voiding any time savings over an ABR screening: a test which is rather lengthy by provides a high degree of specificity.

[Neonatal screening: risk factors and outcome in 4400 children]. / Screening neonatale: fattori di rischio e risultati su 4400 bambini.

The aim of this study was to determine the incidence of neonatal deafness and how effective screening could be in a cohort of infants under the national health service in Mestre Venice. The criteria used in the screening of a population at risk were those established by the JCIH (1990). All the children born between September 1992 and August 1995 (4408 infants) were examined in an attempt to identify risk factors. The children presenting one or more risk factors and those admitted to neonatal intensive care for any reason were submitted to ABR testing. The results were considered negative if the wave V was perceived at an intensity < or = 40 dB nHL. Of the 4408 children screened, a total of 5 were found with a degree of deafness in excess of 50 dB HL. Three children were found to be at risk while two had a silent history. In terms of etiology, 2 children showed genetic transmission, one there had a 21 trisomia while it proved impossible to determine the cause of deafness in the remaining two. As indicated in other studies, application of a risk register makes it possible to identify congenital deafness in 50-60% of the cases. For this reason the authors consider mass screening through the use of oto-acoustic emissions to be quite useful.