Patients with Pendred syndrome: is cochlear implantation beneficial?

Objective: To evaluate the benefit of cochlear implantation in patients with Pendred syndrome.

Design: Retrospective study.

Setting: Tertiary centre.

Participants And Main Outcome Measures: Speech perception was measured using a phonetically balanced word list at a sound pressure level of 65 dB. Post-operative phoneme scores at 12-month for adults and 36-month for children with Pendred syndrome were compared to scores of patients with an enlarged vestibular aqueduct (EVA) and a reference group with an unknown cause of hearing impairment. Quality of life was measured with the Nijmegen Cochlear Implant Questionnaire to evaluate the differences between pre- and post-implantation.

Results: The mean post-operative phoneme scores were as follows: in the Pendred group, 91% (n = 16; SD = 10) for children and 78% (n = 7; SD = 14) for adults; in the reference group, 79% (n = 59; SD = 20) for children and 73% (n = 193; SD = 18) for adults; and in the EVA group, 84% (n = 6; SD = 7) for children and 66% (n = 12; SD = 22) for adults. A significant difference in speech perception was found between the children of the Pendred group and the reference group of 11.4% (SE = 5.2; P = 0.031). Between the adults, a difference of 11.2% (SE = 6.7; P = 0.094) was found. The difference between the Pendred group and the EVA group was 5.7%(SE = 4.5; P = 0.22) for children and 9.9% (SE = 8.7; P = 0.28) for adults. A significant improvement post-implantation in four of the six subdomains of the quality of life questionnaire was found: basic sound perception (P = 0.002), advanced sound perception (P = 0.004), speech production (P = 0.018) and activity limitations (P = 0.018). The two not significant subdomains were self-esteem (P = 0.164) and social interaction (P = 0.107).

Conclusions: After cochlear implantation, children with Pendred syndrome performed better than the reference group with respect to speech perception, however, adults performed similar. No significant differences were found between the Pendred and EVA group. Consequently, during pre-operative counselling, the two groups of patients may be considered comparable in terms of expected speech perception performance after cochlear implantation.