Hearing preservation and cochlear implants according to inner ear approach: multicentric evaluation

Area of Science:

• Otolaryngology
• Audiology
• Neurosurgery

Background:

• Electroacoustic stimulation (EAS) is effective for individuals with low-frequency residual hearing inadequately addressed by hearing aids.
• Preserving residual hearing during cochlear implant surgery is crucial for EAS efficacy.

Purpose of the Study:

• To assess hearing preservation rates in patients following cochlear implant surgery.
• To compare hearing preservation based on different surgical approaches to the inner ear.

Main Methods:

• A soft surgical technique was employed in 19 subjects using the atraumatic MED-EL FLEX™ EAS electrode.
• Pre- and postoperative audiometric tests were conducted, with an average follow-up of 18.4 months.
• Electrode insertion methods (cochleostomy vs. round window) were analyzed.

Main Results:

• Overall hearing preservation was achieved in 89.4% of cases (17 out of 19 patients).
• Five patients experienced total hearing preservation, while two had no preservation.
• Electrode insertion via the round window approach (16 patients) showed no significant difference in preservation compared to cochleostomy (3 patients).
• All implanted patients demonstrated benefit, including those relying solely on electrical stimulation.

Conclusions:

• The soft surgical technique and atraumatic electrode facilitated high rates of hearing preservation in EAS candidates.
• Both cochleostomy and round window approaches yielded comparable hearing preservation results in this cohort.