(PP1107) Study of Newborn Pressurized Otoacoustic Emissions in Neonatal Hearing Screening

Abstract: Study about the application of the Pressurized Otoacoustic Emissions method in Newborns, aiming to
compensate for possible Middle Ear alterations, observed at the time of Neonatal Hearing Screening,
in order to avoid the need for retesting in cases of referral on the screening.

Summary: The Transient Otoacoustic Emissions (TEOAE) have been highly used in the Newborn Hearing Screening (NHS) programs. At the time of the NHS, neonates may have retained amniotic fluid in the middle ear space, what could attenuate stimuli and inhibit the measurement of the TEOAE, resulting in a referral outcome. As a result, retest scheduling is required at a later date, which makes the process longer. It is possible to analyze the tympanic-ossicular system measurements with Wideband Timpanometry (WBT) and perform Pressurized Otoacoustic Emissions (TEOAE-P), which allows the alteration of the pressure of the External Acoustic Meatus (EAM), compensating for a possible alteration in ME and avoiding need of retesting.

Objective:

To verify whether WBT and TEOAE-P are effective methods for evaluating newborns with ME alteration during NHS.

Method:

- It was a cross-sectional observational study. Eighty-seven neonates born at the maternity ward of CAISM/Unicamp were evaluated.

- Procedures performed: Medical Record Analysis; WBT and TEOAE-A and TEOAE-P, at Maximum Compliance Peak Pressure, using Interacoustics Titan equipment.

- Data analysis: was performed by each ear, with parameters: Average signal/noise ratio in Frequency Bands of 0.87KHz, 1.94KHz, 2.96KHz, 3.97KHz and 4.97KHz.

- From the results obtained the sample was grouped into: G1: Passed TEOAE-A and TEOAE-P; G2: Failed on TEOAE-A and Passed on TEOAE-P; G3: Failed on TEOAE-A and TEOAE-P. Parameters used to consider the ‘Pass’ criteria: 3 or more frequency
bands with S/R ratio > 6 and/or Reproducibility > 50%. Statistical Tests used: T-Paired Test for comparison between the TEOAE-A e TEOAE-P and the one-way ANOVA, for comparison between the groups.

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Results:

Was evaluated 103 newborns, totalizing 177 ears. Comparing TEOAE methods, It was observed that in G1 (n=131) there was no statistic significant difference between the average S / R ratio of TEOAE-A and TEOAE-P, indicating that MAE Pressurization in the presence of TEOAE did not alter or improve its levels. In G2 (n = 18), the average S / R ratio was always higher in TEOAE-P, with a
statistic significant difference in all frequency bands. This result may suggest that, in the case of TEOAE-A referral due to changes in OM pressure, MAE Pressurization proved to be an effective strategy for measurement of TEOAE levels. In G3 (n=28), there was also no statistic significant difference between the mean TEOAE S / N ratio and the TEOAE-P, suggesting that, in these cases, the
referral on the TEOAE measurement was not due to a change in pressure of OM; In these cases, retest scheduling was necessary. When comparing the groups, it was observed that TEOAE-A were lower in G2, with a statistic significant difference when compared to G1, what was expected when comparing pass and fail groups. In the comparison of TEOAE-P, its result in G2 was the same as in G1, showing that with the increase of TEOAE when pressurized, its levels were equal to the levels found in G1.

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Conclusion:

In the analyzed, WBT and TEOAE pressurization in neonates was efficient in the cases of referral because of altered Middle Ear conditions.