Mismatch between objective measure and subjective perception of speech recognition in a patient with single-sided deafness and unilateral cochlear implant

We present a case report of a patient with single-sided deafness. She was implanted with a cochlear implant (CI), model Synchrony Flex28 (MED-EL) at the age of 64 years. Residual hearing was preserved. The initial fitting occurred 2 months postop. She achieved a very good speech perception score of 72% (HSM sentence test in noise, SNR 10 dB).

At the follow-up 6 months later the patient was satisfied with her CI and didn’t report any problems. Nevertheless she was unable to perform the speech test in noise. The cause was a failure of the acoustic component. After replacement of the faulty part the patient reported that sound quality didn’t change at all, but a repetition of the speech test led to a recognition score of 79%.

Due to the normal-hearing ear low pitched sound was sufficiently represented. Since localization is not possible with low pitched sound, the patient didn’t recognize any deterioration of speech recognition. Only by means of direct coupling between speech processor and audio source poor speech recognition was revealed.

To conclude, in case of CI users with single-sided deafness, a thoroughly check of external parts is necessary, because subjective perception may not reveal a faulty part. On the other hand it is shown that residual hearing can deliver a significant contribution to speech recognition, especially in noisy environment.

Poster-PDF A-1058.pdf

Publication History

Article published online:
10 June 2020