BiCROS Hearing Aid
A BiCROS (bilateral contralateral routing of signals) hearing aid system is used when a person has hearing loss in both ears but one ear is unaidable, meaning it is too severely impaired to benefit from amplification. A standard CROS system routes sound from a deaf or unaidable ear to a normal-hearing ear. A BiCROS system builds on this by also providing amplification for the better ear, which itself has some degree of hearing loss.
The system works as follows: a microphone on the poorer ear picks up sound from that side and transmits it wirelessly to a hearing aid worn on the better ear. The better ear receives both that transmitted signal and its own amplification through the hearing aid. The result is that sounds from both sides of the environment are made available to the one hearing ear, with the better ear's own hearing loss addressed through the hearing aid component.
BiCROS is appropriate when one ear is too damaged for amplification (due to very severe or profound loss with very poor word recognition) while the other ear has mild to moderate hearing loss. An audiologist assesses candidacy based on audiometric and speech recognition results. The decision between BiCROS and other options such as bone-anchored devices depends on the degree of loss, ear anatomy, and individual listening needs.
