[Stimulation increase in evoked acoustic otoemissions]

Evoked otoacoustic emissions (OEAE) are an excellent evaluation method of the hearing organ and are principally useful in newborn screening. During the performance of this technique, doubtful cases sometimes exist and they are customarily considered as failures of the test, increasing the group of children to be re-evaluated. The program IL088 has the possibility of increasing the stimulus intensity (gain). We applied this gain to all children with doubtful OEAE in attempts to give a pass or fail score.

The record of OEAE was accomplished with the system IL088 v3.5. It was applied to 70 ears of healthy newborns, a gain of +15 dB initially and/or +21 dB (if a pass score was not obtained). Some normal ears were included in this group as controls. Of the explored ears, 23 had a normal OEAE, 17 presented a doubtful response and in 30 cases the answers were negative (fail).

This study demonstrates that in doubtful cases, the usefulness of increasing the gain is very high permitting that these cases accomplish pass criteria (15/17). In the ears with a lack of response there is an increased response, but it usually does not reach a passing level (6/30). In children with normal response the pass rate does not vary.

The increase in gain in ears with a doubtful response offers a high a rentability, reducing the the initial failure rate of OEAE without altering the real failure rate or affecting those that initially pass allowing a reduction in the number of second evaluations.