Clinical Trial Details
— Status: Recruiting
Administrative data
| NCT number |
NCT04906135 |
| Other study ID # |
2018H0344 |
| Secondary ID |
R21DC019458 |
| Status |
Recruiting |
| Phase |
N/A
|
| First received |
|
| Last updated |
|
| Start date |
October 1, 2021 |
| Est. completion date |
June 30, 2025 |
Study information
| Verified date |
April 2023 |
| Source |
Ohio State University |
| Contact |
n/a |
| Is FDA regulated |
No |
| Health authority |
|
| Study type |
Interventional
|
Clinical Trial Summary
Usher syndrome (USH) causes extensive degeneration in the cochlear nerve (CN), especially in
CN fibers innervating the base of the cochlea. As the first step toward developing
evidence-based practice for managing implant patients with USH, this study evaluates local
neural health, as well as the neural encoding of temporal and spectral cues at the CN in
implanted patients with USH. Aim 1 will determine local CN health in patients with USH by
assessing the sensitivity of the electrically evoked compound action potential to changes in
interphase gap and pulse polarity. Aim 2 will determine group differences in neural encoding
of temporal and spectral cues at the CN between patients with USH and patients with
idiopathic hearing loss. Aim 3 will use supervised machine learning techniques to develop an
objective tool for assessing the electrode-neuron interface at individual electrode
locations.
Description:
Usher syndrome (USH) is an autosomal recessive disorder characterized by hearing loss, visual
impairment, and in some cases, vestibular dysfunction. It is the leading cause of hereditary
deaf-blindness in humans. USH causes extensive degeneration in the cochlear nerve (CN),
especially in CN fibers innervating the base of the cochlea. Whereas there is no treatment
for arresting this degenerative process or for restoring visual loss, the restoration of
auditory input is possible with cochlear implantation. Due to the progressive deterioration
in vision, using visual cues for communication will eventually become impossible. Therefore,
the importance of optimizing auditory inputs through cochlear implants (CIs) for patients
with USH is paramount. However, patients with USH have much higher rates of neurological,
mental, or behavioral disorders than the general CI patient population, which limits their
ability to provide reliable behavioral responses or sufficient verbal descriptions of their
auditory perception, especially for pediatric patients. In addition, optimal programming
parameters for CI users with CN damage differ from those used in typical CI users due to
declined CN responsiveness to electrical stimulation. As a result, the clinical programming
process in implanted patients with USH can be extremely challenging. To date, auditory neural
encoding of electrical stimulation in patients with USH has not been systematically
evaluated. Consequently, the field lacks evidence-based practice guidelines for managing
implanted patients with USH. For patients who cannot provide reliable feedback, clinicians
rely on a "trial-and-error" approach for adjusting CI programming settings, which ultimately
may not result in appropriate programming maps for individual patients. Therefore, there is
an urgent need to develop objective clinical tools for optimizing CI settings for these
patients. As the first step toward developing evidence-based practice for managing patients
with USH, this study evaluates local neural health, as well as the neural encoding of
temporal and spectral cues at the CN in implanted patients with USH. Aim 1 will determine
local CN health in patients with USH by assessing the sensitivity of the electrically evoked
compound action potential to changes in interphase gap and pulse polarity. Aim 2 will
determine group differences in neural encoding of temporal and spectral cues at the CN
between patients with USH and patients with idiopathic hearing loss. Aim 3 will use
supervised machine learning techniques to develop an objective tool for assessing the
electrode-neuron interface at individual electrode locations. Results of this study have high
scientific significance because they will establish how CN degeneration affects neural
encoding and processing of electrical stimulation, and identify tests that distinguish the
loss of spiral ganglion neurons from the loss of peripheral axons. Results of this study also
have high clinical significance because they will 1) lay the groundwork for developing
effective, evidence-based clinical practice guidelines for managing patients with USH, and 2)
yield an objective tool for assessing the site-specific electrode-neuron interface in all CI
users, which is foundational for creating optimal programming maps for individual patients.
