2018 Volume 39 Issue 3 Pages 364-370
The purpose of this case study was to clarify the characteristics of tone-in-noise (TIN) test in estimating true puretone thresholds for functional hearing loss. A series of differential audiometries was carried out to a case of teenager (18 years of age, female) with bilateral mild sensori-neural hearing loss, who was also complicated by functional hearing loss. Obtained thresholds of puretone and SRT showed severe hearing loss, whereas the results of ABR and DPOAE showed mild hearing loss. In the results of TIN test, (1) improbable thresholds shifts (10～20 dB) were found in ipsilateral masking, when narrow-band noises were presented at the same effective masking levels equal to the feigned puretone thresholds, (2) as decreasing noise levels, the responsive puretone thresholds proportionally descended, and (3) the noise detection levels showed similar values within 15 dB to the previous true puretone thresholds obtained in 13 years of age. The findings suggested that the noise detection levels in TIN test could estimate true puretone thresholds in the case with functional hearing loss.
