Instant Auditory Benefit of an Adhesive BCHD on Children with Bilateral
Purposes: To evaluate the instant auditory benefit of an adhesive bone
conduction hearing aid (ADHEAR) on children with bilateral congenital
microtia, especially the sound localization ability under unilateral and
bilateral fitting. Methods: Twelve patients with bilateral congenital
microtia aged from 6 to 17 were included in this study. Pure tone
threshold under sound field, speech recognition threshold in quiet and
sound localization abilities were tested and compared before and after
wearing the device. The pure tone threshold test was additionally
repeated for two different wearing method – adhesive or fixed with
softband; the sound localization test was repeated for both unilateral
and bilateral fitting. Correlation analysis was then conducted to find
the influencing factors of sound localization improvement. Results:
Significant auditory improvement were found: the average pure tone
threshold (PTA) reduced by 24.8 (adhesive) and 27.3 dB HL (softband),
with no significant difference between the two wearing methods. The
speech recognition threshold also improved by 29.0 dB. As for sound
localization abilities, no significant improvement was found under
unilateral fitting; but half (6 of 12) of the patients were notably
benefited from bilateral fitting. The improvement was found to be strong
correlated with the patients’ unaided sound localization ability –
those with poorer localization abilities tends to benefit more.
Moreover, it was found that the sound localization improvement was also
negatively related with the malformation degrees of the patients’ head.
Summary: ADHEAR affords significant auditory benefits for children with
bilateral congenital microtia, in terms of sound and speech perception.
The sound localization abilities could be partly improved instantly by
bilateral fitting, and the improvement is related with factors such as
adaption and skull malformations.