Non-auditory stimulation in adult cochlear implant users

Area of Science:

• Otorhinolaryngology
• Neurosurgery
• Biomedical Engineering

Background:

• Multichannel cochlear implants (CI) offer significant hearing restoration.
• Non-auditory stimulation (NAS) can occur, presenting as facial nerve stimulation or pain.
• Understanding NAS incidence and contributing factors is crucial for optimizing CI outcomes.

Purpose of the Study:

• To determine the incidence of NAS in adult CI recipients.
• To identify factors associated with NAS, including patient history and electrode placement.
• To evaluate the effectiveness of programming strategies in managing NAS.

Main Methods:

• Retrospective case review of 163 adult CI recipients (1988-1998).
• Analysis of device types (Nucleus, Med-el), patient diagnoses, and electrode locations.
• Correlation of NAS events (facial nerve stimulation, pain) with clinical factors and programming adjustments.

Main Results:

• NAS occurred in 23.9% of patients: 12.3% facial nerve stimulation, 11.0% pain.
• Otosclerosis was linked to facial nerve stimulation; skull base fracture to pain.
• Electrode location influenced NAS: base turn for pain, distal for facial nerve stimulation.
• Programming strategies successfully eliminated NAS in all affected patients.

Conclusions:

• NAS is a notable complication of multichannel CI, influenced by patient factors and electrode positioning.
• Shorting of current through low-resistance temporal bone areas is a likely mechanism.
• Effective management strategies exist, ensuring no adverse impact on speech perception scores.