Background:
In hearing preservation cochlea implantation the decision has to be made between a short electrode array with a low risk of hearing loss versus a long array with a larger cochlea coverage for electric stimulation only. Partial insertion of a longer electrode offers a solution for progressive hearing loss with afterloading of the electrode array.
Methods:
24 patients were implanted using partial insertion of a 24 mm electrode (16 mm insertion depth) and a 28 mm electrode (insertion depth 20 mm). Hearing preservation and speech perception in noise were examined.
Results:
The median hearing loss with 16 mm insertion was 6 dB, for 20 mm 17 dB. All patients use EAS with a median of 80% in HSM in sentence test in noise (10 dB SNR)
Discussion:
A partial insertion allows a good hearing preservation. Patients will benefit from EAS with excellent speech perception results in noise. In case of progressive loss the electrode can be inserted deeper to increase the cochlea coverage for electric stimulation only.
