Contralateral hearing aid use in cochlear implanted patients: multicenter study of bimodal benefit

Area of Science:

• Audiology
• Neuroscience
• Biomedical Engineering

Background:

• Many cochlear implant (CI) users retain some hearing in the non-implanted ear.
• Contralateral hearing aid (HA) use with a CI may offer binaural benefits.
• Optimization of HA fitting is crucial for maximizing benefits.

Purpose of the Study:

• To evaluate the binaural benefits of using a contralateral HA with a CI.
• To assess the impact of HA fitting optimization on performance.
• To compare bimodal (CI + HA) performance against monaural (CI alone or HA alone) conditions.

Main Methods:

• Prospective, repeated-measure, multicenter study with 15 adult CI users.
• Intra-subject design comparing CI alone, HA alone, and CI + HA conditions.
• Performance evaluation included speech understanding in quiet and noise, and sound localization before and after HA fitting optimization.

Main Results:

• Bimodal listening significantly improved speech perception in quiet and noise compared to monaural conditions (p < 0.01).
• Bimodal use demonstrated binaural summation and a significant binaural squelch effect.
• Sound localization ability was significantly enhanced with bimodal fitting (p = 0.002).

Conclusions:

• The combination of a hearing aid and cochlear implant significantly improves speech perception and sound localization.
• Bimodal fitting provides superior auditory performance compared to using a CI or HA alone.
• No significant functional performance differences were found after HA fitting optimization.