Cochlear implantation with Slim Modiolar Electrode carriers enables hearing preservation.

Abstract

Purpose: To investigate hearing preservation in patients who received a cochlear implant with a preformed electrode carrier, namely the Slim Modiolar (SM).

Methods: A monocentric, retrospective study was conducted. A total of 51 adult patients (24 females, 27 males), representing 60 ears, were included in the final evaluation. The mean age was 60.9 ± 15.2 years (range 17.5-89.7 years). All patients had some degree of residual hearing. Frequency-specific pure-tone audiometry was performed at three time points: preoperatively (T0), within 30 days postoperatively (T1), and at a later time point during follow-up (T2; 20.7 ± 17.6 months). Low frequency pure tone average and the HEARRING group formula were used to facilitate comparison of hearing preservation rates with other results published so far.

Results: In the first month after surgery, no significant deterioration was observed for the low frequencies, but a significant deterioration was observed at follow-up. Using the HEARRING classification system, the average short-term (T0-T1) hearing preservation score was 70%, which corresponds to partial hearing preservation. During follow-up (T0-T2), the score decreased to 61% in the study group, still representing partial hearing preservation. Complete hearing loss occurred in 20% of the cases.

Conclusion: Especially in the low frequency range, the utilisation of SM electrode carriers during cochlear implantation facilitates preservation of residual hearing.