Residual Hearing Preservation with the Evo® Cochlear Implant Electrode Array: Preliminary Results

Area of Science:

• Otolaryngology
• Neurosurgery
• Biomedical Engineering

Background:

• Preserving residual hearing is crucial for cochlear implant (CI) patients, enabling combined electric-acoustic stimulation.
• Combined stimulation enhances speech perception and sound quality.
• Developing soft surgery techniques and specialized electrodes is key for hearing preservation.

Purpose of the Study:

• To evaluate a soft surgery approach for hearing preservation in patients with low-frequency residual hearing.
• The approach combines round-window insertion, dexamethasone, and hyaluronic acid with a straight, soft electrode array.

Main Methods:

• A pre-clinical trial involving seven patients with low-frequency residual hearing.
• Surgical technique included round-window insertion and topical dexamethasone application.
• The EVO electrode was used in the soft surgery protocol.

Main Results:

• The soft surgery protocol was successfully implemented in five out of seven patients.
• In the successful cases, average hearing threshold shifts were 18.7 dB HL up to 500 Hz and 15.7 dB HL up to 1 kHz.
• These results indicate satisfactory levels of residual hearing preservation.

Conclusions:

• The EVO electrode facilitates residual hearing preservation in cochlear implantation.
• A soft surgical approach incorporating round-window insertion and specific medications (dexamethasone, hyaluronic acid) achieves significant hearing preservation.