Optimization of remote assessment in cochlear implant recipients.

Cochlear implantation is the established standard of care for rehabilitation of
patients with severe to profound hearing loss. Patients getting an cochlear
implant (CI) follow an intensive rehabilitation program in order to make
optimal use of the implant. After this rehabilitation phase, patients need
aftercare and monitoring for the rest of their lives. Patient management and
monitoring therefore leads to an increasing cumulative workload for CI-centers.
Additionally, technological advances have led to expanding cochlear implant
candidacy in recent years (Snel-Bongers et al., 2018), contributing to a
furtherly increased workload.

A visit to the clinic generally consists of subjective testing (e.g. a speech
recognition test), objective testing (e.g. impedance measurements) and the
patients* evaluation of, for example, sound quality or hearing performance by a
clinician. Based on the gathered information, the clinician adjusts the
settings of the processor.

In managing the increasing workload, growing interest has been shown in remote
hearing care, also for cochlear implants. Researchers have shown that remote
testing of speech recognition (De Graaff et al., 2016; de Graaff et al., 2018,
2019; Goehring et al., 2012; Hughes et al., 2012) and evaluation of objective
parameters such as impedances or electric compound action potentials (eCAPs)
(Hughes et al., 2012; Parreño et al., 2020) is feasible. Regarding remote
speech recognition testing, which is of paramount importance in clinical care,
it was found that background noise and reverberation had a severe influence on
speech recognition scores in remote sites compared to the clinic (Goehring et
al., 2012; Hughes et al., 2012). This problem can be circumvented by making use
of increased connectivity capabilities of modern CI processors, where audio
input can be presented through dedicated audio cables (De Graaff et al., 2016;
de Graaff et al., 2018, 2019) or, in newer generations of sound processors,
direct streaming. In these studies, it was found that clinical results
sometimes deviated when measured via loudspeaker compared to direct audio
input. Additionally, patients in general were positive about remote testing but
sometimes had difficulty using the experimental setup.

A future project will focus on a new platform for at-home monitoring and
testing of cochlear implants, developed by one of the manufacturers of cochlear
implants, Advanced Bionics (AB). Their Research Application allows for
clinicians to read out the technical status of the implant and sound processor,
but can also be used for audiological testing using direct Bluetooth streaming,
or perform a subjective rating of hearing performance by the patient by means
of questionnaires. Before studying the at-home application, it must be
determined whether results that are obtained via direct Bluetooth streaming and
self-scoring are the same, and as reliable, as clinical testing. Moreover, this
needs to be evaluated thoroughly for multiple tests that are done in our
clinic, which earlier studies did not include.

This study is a prospective, single-centre, cross-sectional study. The total
duration of the study is estimated to be 1 year. Cl users and normal-hearing
subjects are included as study groups. The CI subjects will participate in a
maximum of 4 test days. The normal hearing controls in one to two test days.
Each test day consists of a test session that lasts for approximately 2 hours,
with breaks between if needed. The setting is the LUMC ENT department, where
the CI subjects have already followed similar procedures as part of their
regular clinical program.

There is minimal risk involved. Subjects use their regular clinical
programming. The only predictable risk, for both the CI users and normal
hearing subjects, is that they have to listen in a challenging listening
environment, potentially leading to mild fatigue.

Benefits to the Cl population would be 1) an extra test moment, adding to the
monitoring that is done as part of their regular clinical follow-up, 2) extra
insight in their own performance with CI, as the clinical test battery is
extended with extra tests and 3) in case there are equivalent results between
the two presentation modes, this might allow the bulk of CI patients to
self-test at home in the future, reducing the need to come into the clinic.
There is no direct benefit for normal hearing subjects.