CROS and Quality of Life of Elderly Cochlear Implant Recipients and Their Care Givers

The purpose of this study is to assess the effect of the Naida Link contralateral routing of signal (CROS) device on speech understanding in challenging listening situations and on the quality of life in unilateral CI recipients and their frequent communication partners. We hypothesize that:

1. Unilateral CI recipients will obtain higher speech understanding scores with the CROS device in challenging listening conditions
2. Use of the CROS device will lead to positive changes in ratings on Quality of Life measures for (i) unilateral CI recipients, and (ii) their frequent communication partners

A frequent communication partner (FCP) is an individual (a family member, or a friend, or a care taker, or a significant other, or a colleague, etc.) who has at least two hours of in-person interactions with the CI recipient every week.

Cochlear Implants (CI) are now a well-accepted treatment for individuals with severe to profound hearing impairment. Compared to using one CI, bilateral CIs are known to provide access to some of the benefits of binaural hearing like improved speech understanding in noise (primarily due to headshadow), improved localization, reduced stress and fatigue, and improved quality of life (e.g., Dunn et al. 2012, Litovsky et al. 2012, Härkönen et al. 2016, Reeder et al. 2014, Agrawal 2008). However, a number of CI recipients are unable to or choose not to be implanted bilaterally for many reasons. Those with acoustic hearing in the contralateral ear can benefit significantly by using a hearing aid in that ear (bimodal hearing) (Ching et el. 2006, Dorman and Gifford 2010, Dorman et al. 2015, Dunn et al. 2005, Firszt et al. 2012, Illg et al. 2014, Farinetti et al. 2015).

Unilateral CI recipients do not have access to advantages of bilateral and bimodal hearing. In addition to reduced speech understanding in noise, especially when the speech source is located towards the non-CI, they can also experience increased stress and fatigue. Studies have shown that a CROS device, when worn on the contralateral, non-implanted ear, can help overcome speech understanding deficits due to head-shadow. The effect of such technology on quality of life of the CI recipient and their frequent communication partners has not been evaluated over an extended duration of use.

Study methodology:

Fourteen unilateral CI recipients will participate in this study. Testing will be conducted at the University of Utah Hospital ENT clinic. The study will comprise of 2 clinic visits separated by a take-home phase of 6 months. A designated FCP will be a part of each study visit, preferably.

Following are the test measures for CI recipients:

* Questionnaires
* Data logs
* Pure-tone audiometry
* Speech intelligibility

Following are the test measures for FCPs:

• Questionnaires

Speech testing will be conducted in a sound booth with a two speaker set-up (± 90°). AZBio sentences (Spahr et al., 2012) presented at 65 dB A will be the target stimuli. The interferer will be a multi-talker babble. The babble will be presented at an individualized level for each participant where their performance in noise in SCROS(Off)NCI configuration is half of their performance in quiet in SCROS(Off) configuration.

Study devices: For speech testing in the sound booth, a study Naida CI Q90 sound processor will be used. For the take-home phase, recipients will use their own Naida CI processor (Q70 or Q90). A Naida Link CROS will also be used for sound-booth testing as well as the take-home phase.

Workflow:

After recruiting, following will be mailed to the participants to be completed prior to the study visit and hand carried to visit 1:

For each CI subject:

(i) Informed consent form (ii) APS-SSD (Schafer et al, 2013, modified by H. Snapp, 2017) (iii) Nijmegen questionnaire (adapted from Hinderink et al, 2000)

For each CI subject's frequent communication partner:

(i) Informed consent form (ii) SOS-HEAR

Eligibility Criteria:
Inclusion Criteria:

* Unilateral recipients of Advanced Bionics CII/90K/Ultra implants
* Ages 18 years and above
* At least 6 months of CI use experience
* Current users of a Naida CI Q70 or Q90 processor
* Do not currently use a Naida Link CROS device
* Limited usable/aidable hearing in the contralateral ear
* Fluent in spoken English
* Willingness to use the CROS device regularly for the study duration
* Willingness to follow-up on a biweekly/monthly basis

Exclusion Criteria:

* \< 6 months of CI use experience
* \< 30% sentence recognition scores in quiet with unilateral CI
* Inability to participate in speech testing
* Inability to follow and complete questionnaires
* Inability to designate an FC
* not a unilateral recipient of Advanced Bionics CII/90K/Ultra implants

Frequent communication partner (FCP) participants' inclusion criteria:

* Ages 18 years and above
* Fluent in spoken English
* Willingness to participate in the study
* Spends at least two hours of in-person interactions with the recipient of Advanced Bionics CII/90K/Ultra implants every week.

FCP's Exclusion criteria:

* Under the age of 18 years
* Not fluent in spoken English
* Spends less than two hours of in-person interactions with the recipient of Advanced Bionics CII/90K/Ultra implants per week