Insertion of Cochlear Implant Electrode Array Using the Underwater Technique for Preserving Residual Hearing

Area of Science:

• Otolaryngology
• Neurosurgery
• Biomedical Engineering

Background:

• Cochlear implantation is a surgical procedure to restore hearing in individuals with severe to profound hearing loss.
• Preserving residual hearing is crucial for optimal outcomes in cochlear implant recipients, particularly those with some pre-existing hearing.
• Minimizing trauma during electrode insertion is essential to protect delicate cochlear structures.

Purpose of the Study:

• To describe and evaluate a novel underwater technique for cochlear implantation.
• To assess the efficacy of this technique in preserving residual hearing post-surgery.

Main Methods:

• A retrospective review of 15 cochlear implantations performed using the underwater technique.
• Patients included children and adults with pre-operative residual hearing at low to mid frequencies.
• The technique involves filling the tympanic cavity with Ringer solution before electrode insertion.

Main Results:

• Hearing preservation was achieved in 13 out of 15 patients (87%) at 6-8 weeks post-surgery.
• At an average follow-up of 15.2 months, 9 patients (64%) maintained measurable residual hearing.
• No residual hearing was measured in 5 patients (36%) at the late follow-up.

Conclusions:

• The underwater technique provides a reliable and nontraumatic method for cochlear electrode insertion.
• This approach respects cochlear physiology and minimizes pressure variations during surgery.
• The technique shows promise for hearing preservation in cochlear implantation.