The current status of audiologic rehabilitation for profound unilateral sensorineural hearing loss

Audiologic rehabilitation of individuals with profound unilateral sensorineural hearing loss (USNHL) has traditionally been limited to the use of air-conduction contralateral routing of sound (CROS) hearing aids. Treatment for these individuals has expanded with new applications of the bone-anchored hearing aid (BAHA), transcranial hearing aid (t-CROS), and the cochlear implant. In this article, the authors review the literature that addresses these various treatment options.

Contemporary review

Historical information is available that describes the limited efficacy of air-conduction CROS hearing aids in lifting hearing handicap associated with USNHL. Current investigations on providing cross hearing are generally focused on use of the BAHA. Little is known at present whether new developments in hearing aid technology can improve on conventional air-conduction CROS or t-CROS approaches. Interestingly, the cochlear implant seems to be a viable option for individuals with USNHL and tinnitus who also have intact auditory nerve pathways.

There is indication in the literature that BAHA provides greater relief of hearing handicap associated with USNHL than CROS hearing aids; however, both have been found to provide limited patient satisfaction and seemingly fall short of restoring true sound localization. Adequate trials have not been performed comparing BAHA with the best CROS hearing aid technology. Transcranial hearing aids and cochlear implants are experimental methods to treat USNHL and hold promise, although there remains a lack of studies available to fully support this.