Recipients With Limited Bimodal Benefit: HA or CROS

The rationale is to determine (in individuals with limited perceived bimodal benefit) whether the CROS device may be a better solution for obtaining two-sided input. If yes, this study would be practice-changing.

It is well accepted that bilateral input can significantly improve speech understanding in noise for patients with cochlear implants. For cochlear implant (CI) recipients who have a CI on only one side, two sided input can be provided with simultaneous use of a hearing aid (HA) or a CROS device on the opposite side. The decision about which device to use depends on the level of residual hearing a recipient has in non CI-implanted ear, and more specifically what level of useable residual hearing s/he has. Access to useable low frequency hearing can not only improve speech understanding in noise, it can also improve sound quality, pitch perception and music perception. Clinicians can reasonably predict that a recipient with hearing thresholds better than 60 dB HL at low frequencies (below 750 Hz) would benefit from amplification. For recipients with no measurable acoustic hearing in the contralateral ear, CROS would be a reasonable option, especially if bilateral implantation is not feasible or desired. However, it is more difficult to predict the appropriate device in individuals who have some measurable acoustic hearing but may be receiving limited benefit from it. This can be especially challenging because audiometric thresholds are not a reliable predictor of bimodal benefit. Additionally, acoustic hearing can provide subjective benefits which could hold different intrinsic value or significance for different individuals depending on their life style and listening needs.