Cochlear Implantation in Nontraditional Candidates

Abstract

Objective Traditionally, children are cochlear implant (CI) candidates if bilateral severe to profound hearing loss is present and amplification benefit is limited. The current study investigated abilities of adolescents with asymmetric hearing loss (one ear with severe to profound hearing loss and better hearing contralaterally), where the poorer ear received a CI and the better ear maintained amplification. Study Design Within-subject case study Setting Pediatric hospital, outpatient clinic Patients Participants were five adolescents who had not met traditional CI candidacy due to one better hearing ear, but did have one ear that met criteria and was implanted. All maintained hearing aid (HA) use in the contralateral ear. In the poorer ear pre-implant, three participants had used amplification and the other two had no HA experience. Main Outcome Measure Participants were assessed in three listening conditions: HA alone, CI alone, and both devices together (bimodal) for speech recognition in quiet and noise, and sound localization. Results Three participants had CI open-set speech recognition and significant bimodal improvement for speech recognition and localization compared with the HA or CI alone. Two participants had no CI speech recognition and limited bimodal improvement. Conclusions Some adolescents with asymmetric hearing loss who are not typical CI candidates can benefit from a CI in the poorer ear, compared to a HA in the better ear alone. Additional study is needed to determine outcomes for this population, especially those who have early onset profound hearing loss in one ear and limited HA experience.

Cochlear implantation and single-sided deafness

“…This study suggests that perhaps there are some limitations in improving localization in patients with pre or peri-lingual deafness 21 . A more recent study by Firszt reported 3 of 5 adolescents with unilateral hearing loss had improved speech recognition and sound localiation 28 .…”

Asymmetric and unilateral hearing loss in children

“…It has been long established that binaural hearing provides improved speech perception, improved localization of sound, increased loudness perception due to binaural summation, and overall improved hearing both in noisy and quiet environments (Cadieux, Firszt, & Reeder, 2013; Ching, van Wanrooy, & Dillon, 2007). Ease of listening has been more recently identified to be a binaural benefit.…”

“…Even though children with single-sided deafness were not initially recommended cochlear implants due to the hearing in the normalhearing ear being “too good,” implantation has been shown to be successful in children with AHL or UHL (Dwyer, Firszt, & Reeder, 2014; Hassepass et al, 2013). In addition, while not yet considered the standard of care, implant centers are beginning to implant children with AHL, and so far are reporting positive results by implanting the poorer-hearing ear (Cadieux et al, 2013). As previously mentioned, however, instituting speech therapy and IEPs for children with UHL does not completely eliminate the risk of future academic difficulties (J.…”

Limiting asymmetric hearing improves benefits of bilateral hearing in children using cochlear implants

“…These studies reveal benefits of bimodal hearing over the use of a cochlear implant alone but continued challenges for listening to speech in noise. Data from some children with better hearing in the non-implanted ear also reveal bimodal improvements in speech perception and spatial hearing that depend on duration of deafness in the poorer ear and access to consistent sound in the better ear 11,12,28,51 . The cohorts of bimodal users represent a very diverse population of implant users 28,51–54 .…”

“…We thus sought to promote bilateral hearing development by providing the most appropriate device in each ear to our large cohort of children with deafness 7 . A cochlear implant was provided in ears with severe/profound deafness; children with bilateral deafness received two cochlear implants whereas children with better hearing in one ear received one cochlear implant and a hearing aid in the other, better hearing, ear (bimodal hearing) 7,11–13 .…”