Clinical Trial Details
— Status: Enrolling by invitation
Administrative data
| NCT number |
NCT03306082 |
| Other study ID # |
150417 |
| Secondary ID |
R01DC014037 |
| Status |
Enrolling by invitation |
| Phase |
N/A
|
| First received |
|
| Last updated |
|
| Start date |
June 23, 2015 |
| Est. completion date |
May 31, 2026 |
Study information
| Verified date |
December 2023 |
| Source |
Vanderbilt University Medical Center |
| Contact |
n/a |
| Is FDA regulated |
No |
| Health authority |
|
| Study type |
Interventional
|
Clinical Trial Summary
Cochlear implants are surgically implanted devices which restore the ability to hear to the
hearing impaired. While remarkably successful, even in the best of performers restoration of
hearing to levels of normal listeners is unusual. Approximately 3 weeks after surgery,
cochlear implants are activated via mapping - a process in which each individual electrode
(FDA approved cochlear implants have between 12 and 22 electrodes) is turned on and the
stimulus level adjusted to a level that is comfortable and beneficial to the recipient. At
present, this standard of care mapping procedure is performed without knowledge of the
physical location between the cochlear implant electrodes and the neural interface. The
research team has developed a new method of mapping using post-operative CT scans and image
processing to specify the physical relationship between the cochlear implant electrodes and
the neural interface allowing customized mapping. Using this information, the investigators
deactivate sub-optimally positioned electrodes. The investigators term this "Image-guided
Cochlear Implant Programming" (IGCIP). The study collects data in a prospective fashion for
those CI recipient undergoing IGCIP.
Description:
Over 320,000 individuals have received cochlear implants (CIs) to restore hearing to the
hearing impaired. Commercially available CIs have 12, 16, or 22 independent electrodes (the
number is dependent on the manufacturer of the CI) which cover the entire frequency spectrum
of the cochlea from 20,000 Hertz (Hz) at the base of to 200Hz at the apex. After
implantation, an audiologist individually adjusts stimulation levels of each electrode
following which all electrodes are turned on such that the whole frequency spectrum of speech
can be appreciated. This is known as "standard of care" (SOC) programming. While
postoperative speech understanding is significantly better than preoperative levels, even the
best performers complain that the fidelity of natural hearing is not reproduced.
Additionally, a significant minority achieves poor outcomes despite normally functioning
equipment for reasons that are unknown but likely relate to poor neural survival; however,
this cannot be confirmed as postmortem histopathology is required to accurately document
spiral ganglion cell count. In recent years much attention has focused on the interface
between the cochlear implant electrodes and the auditory neurons they are stimulating.
Technological improvements at Vanderbilt in imaging processing have made it possible to
determine the location of each electrode array in relationship to the frequency spectrum of
the cochlea. Using this information, the investigators have developed a new method of CI
programming which they call image-guided cochlear implant programming, or IGCIP in which
sub-optimally placed electrodes are turned-off or deactivated. Sub-optimally placed
electrodes are defined as ones for which their neighboring electrodes are in closer proximity
to the site of their neural stimulation. By deactivating sub-optimally positioned electrodes,
channel interaction is reduced allowing a cleaner signal to be presented to the auditory
nerve. The purpose of the study is to prospectively collect audiological outcomes on patients
undergoing IGCIP. The investigators hypothesize that CI recipients will perform better with
IGCIP as compared to SOC.
Cochlear implant recipients who have reached asymptotic improvement in performance with SOC
will be offered enrollment. They will undergo post-operative CT scanning to determine the
relationship between the cochlear implant electrodes and the neural interface.
Recommendations regarding deactivation of sub-optimally placed electrodes will be
communicated to the audiology team who, if in their clinical judgement deems deactivation of
these electrodes reasonable, will implement the changes for a 1 month trial. The participant
will return at 1 month to have audiological assessment as per the clinical standard of care.
Based on these results, which will be shared with the patient, the patient can choose to use
IGCIP or SOC for long term cochlear implant programming.
