Cochlear Implants in Single-Sided Deafness

Abstract

Single-sided deafness presents a unique challenge to otolaryngologists and audiologists. While the normal hearing ear may allow listeners to perform adequately on audiometric screening, individuals with only one functioning cochlea suffer when resolving speech in noisy environments and in sound localization-which both contribute to a reduced quality of life. Though there are a variety of strategies that provide contralateral routing of sound signals, the cochlear implant is the only treatment to truly restore binaural hearing. Only very recently has cochlear implantation (CI) for singlesided deafness begun in earnest, with encouraging results that demonstrate the strengths and pitfalls of implantation over traditional extracochlear methods. The purpose of this review is to update the field by emphasizing binaural benefits, discussing historical treatments of single-sided deafness, critically evaluating recent data on outcomes of CI for single-sided deafness, and recommending indications for cochlear implants in single-sided deafness in children, adults, and subjects with concurrent ipsilateral tinnitus.

Cortical reorganization after cochlear implantation for adults with single-sided deafness

“…The prevalence of SSD is estimated to affect 3–6% of the general population [ 4 ]. The most common etiologies in adults are sudden sensorineural hearing loss (SNHL), Meniere’s disease, temporal bone traumatism, ototoxicity (drugs and/or noise) and vestibular schwannoma [ 5 ].…”

Effects of insertion depth on spatial speech perception in noise for simulations of cochlear implants and single-sided deafness

“…In daily life, the hearing difficulties encountered by individuals with single-sided deafness (SSD) are often underestimated, as some people believe that normal hearing in only one ear is sufficient to ensure a relatively normal auditory experience (Giardina et al, 2014). Recent research has shown that SSD patients face significant hearing challenges in complex or noisy environments, and in localizing or lateralizing sound sources (Firszt et al, 2012; Kamal et al, 2012; Vermeire et al, 2009).…”

“…Hearing rehabilitation of SSD patients has recently drawn much attention. Treatment with conventional contralateral routing of signal (CROS) or bone-anchored hearing aid (BAHA) have shown limited success (Baguley et al, 2006; Bishop et al, 2010), as these approaches cannot provide any bilateral auditory input (van Zon et al, 2015; Giardina et al, 2014). Cochlear implants (CIs) are able to provide bilateral auditory input in conjunction with contralateral normal hearing.…”

“…SSD patients have benefitted from cochlear implantation in terms of localization, tinnitus reduction, and quality of life (e.g., Tavora-Vieira et al, 2013; Tokita et al, 2014; van Zon et al, 2015). However, the benefits of cochlear implantation for speech understanding in noise have been more variable and in many cases, very limited, depending on which aspect of binaural hearing is tested (e.g., van Zon et al, 2015; Giardina, 2014). …”

Effects of SoundBite Bone Conduction Hearing Aids on Speech Recognition and Quality of Life in Patients with Single-Sided Deafness

“…SSD patients cannot accurately determine the sound source and need to turn their heads to find the sound. Moreover, speech recognition is not ideal in a noisy environment, which greatly affects the quality of life of patients [ 31 , 32 ]. The abbreviated profile of hearing aid benefit (APHAB) hearing aid gain scale is usually used to evaluate the benefit of SoundBite.…”