Evaluation of Electrode-modiolus Distance and Cochlear Fibrosis Using Depth Sounding and Spectroscopy Tools

NCT ID: NCT05402969

Last Updated: 2024-05-29

Study Results

Results pending

The study team has not published outcome measurements, participant flow, or safety data for this trial yet. Check back later for updates.

Basic Information

Get a concise snapshot of the trial, including recruitment status, study phase, enrollment targets, and key timeline milestones.

Recruitment Status

RECRUITING

Total Enrollment

180 participants

Study Classification

OBSERVATIONAL

Study Start Date

2023-01-12

Study Completion Date

2025-01-12

Brief Summary

Review the sponsor-provided synopsis that highlights what the study is about and why it is being conducted.

Cochlear fibrosis development can compromise the success and the outcomes of the cochlear implantation (CI) thus affecting the quality of life of the implanted patient. Correlating the results of the Transimpedance Matrix (TIM) measurements to the implant electrode location determined by the Cone Beam Computer Tomography (CBCT), this study aims to identify a range of TIM profiles within the implanted population, certain profiles suggesting the growth of the fibrosis tissue in cochlea

Detailed Description

Dive into the extended narrative that explains the scientific background, objectives, and procedures in greater depth.

Fibrosis tissue growth after the CI is an inflammatory reaction to a foreign body occurring around the electrode array. It is considered responsible for a larger current diffusion, less precise stimulation of auditory nerve fibres and elevated electrical impedances thus affecting the functioning and the battery life of an implant. Fibrosis has been also proposed as a factor reducing residual hearing. Hence, its early detection and prevention can significantly improve the outcomes of CI.

To date, no reliable technique to visualise cochlear fibrosis in vivo exists. However, the TIM measurement developed by Cochlear® including depth sounding and spectroscopy tools could possibly provide a better "view" of the fibrosis apparition after CI. This approach has been already successfully applied in the University Hospital of Montpellier, France, to the patients-users of the Advanced Bionics cochlear implants.

One of the factors provoking the fibrosis tissue development is an electrode positioning into the scala vestibule (SV) versus scala tympani (ST). CBCT will be used to visualise the electrode location as well as possible damages of the inner ear caused by CI. The imaging data will be then linked to the TIM measurements results.

Potential participants will be recruited from the French population of the Cochlear® implant users either coming for their regular checks-up at the ENT service of the University Hospital of Montpellier and implanted for more than 6 month (time necessary for the fibrosis tissue to develop) or recently implanted at the same hospital.

For the patients with long-term implantation (160 participants planned) the TIM measurements will be performed only once whereas the newly implanted group (20 participants planned) will require these measurements to be repeated several times: on the day of the surgery as well as 15 days, 1 month, 2 months, 3 months and 6 months after it. For the first group the post operational CBCT imaging file will be extracted from the patient medical record; for the second group CBCT will be performed during the surgery.

The main objective of this study is:

For the group with long-term implantation - to show the difference in TIM profiles according to the electrode scala position (ST or SV) determined by CBCT 6 months or more after the implantation For the group with recent implantation - to evaluate the changes in TIM profiles with time according to the electrode scala position (ST or SV) determined by CBCT

The secondary objectives are common for both groups:

* To analyse various patient subgroups defined by the electrode type (Contour Advanced - only for long-term implantation, Slim Straight, Slim Modiolar) and the inner ear access (round window, enlarged round window or cochleostomy)
* To identify the TIM profile threshold values, potential indicators of the cochlear fibrosis apparition, depending on the electrode type
* To evaluate the depth sounding tool accuracy for the measurement of the distance between the electrode and the spiral ganglion in comparison to CBCT depending on the type of the electrode array.
* To evaluate the spectroscopy tool accuracy for fibrosis detection in specific cochlear areas (around electrodes dislocated to SV or basal electrodes in case of cohleostomy)

Conditions

See the medical conditions and disease areas that this research is targeting or investigating.

Sensorineural Hearing Loss Fibrosis

Study Design

Understand how the trial is structured, including allocation methods, masking strategies, primary purpose, and other design elements.

Observational Model Type

COHORT

Study Time Perspective

OTHER

Study Groups

Review each arm or cohort in the study, along with the interventions and objectives associated with them.

Patients with long-term implantation

Patients undergone CI more than 6 months ago. After the study is presented to the patient and the egligibility criterias are verified, the patient is proposed to sign a consent form (visit 0). Once the consent form is signed, the visit 1 is scheduled (0 to 90 days after the visit 0). During the visit 1 TIM measurements are performed, including depth sounding and spectroscopy, and adversed affects if any are collected.

Transimedance Matrix measurements

Intervention Type PROCEDURE

TIM measurements are based on cochlear implant back-telemetry function. Each electrode contact is stimulated in monopolar mode. Transimpedance is represented by the ratio between the voltage measured at each recording electrode and the current injected at the stimulation contact. The result of the measurements is a matrix of 21x21 transimpedances. Stimulation current cannot be perceived by a patient thus making TIM measurements a non-invasive and painless procedure. The test duration is only 2-3 minutes

Depth sounding and spectroscopy

Intervention Type PROCEDURE

Depth sounding and spectroscopy are based on the matrixes obtained after TIM imaging. Deep sounding measures the capacitances throughout the electrode array whereas spectroscopy determines the phase of every transimpedance value. These tests take 10 to 15 minutes together. The stimulation intensity used by depth sounding technique can be perceived by a patient. If it is considered as unpleasant, the test will be stopped.

Cone Beam Computer Tomography

Intervention Type PROCEDURE

CBCT is a routine postoperative assessment after CI, non-invasive and painless for patients.

Recently implanted patients

Patients enrolled at their pre-op appointments (visit 0 - egligibilty criterias are verified and the consent collected). Visit 1 (0 to 90 days after visit 0) is a surgery. TIM measurements, icluding deep sound and spectroscopy, are performed after the CI and all adverse events are noted. CBCT is routinely done the next day after CI. TIM measurements (as well as adverse event collection) are repeated during visits 2, 3, 4, 5 and 6 (appoitments 15 days, 1, 2, 3 and 6 months after the surgery).

Transimedance Matrix measurements

Intervention Type PROCEDURE

TIM measurements are based on cochlear implant back-telemetry function. Each electrode contact is stimulated in monopolar mode. Transimpedance is represented by the ratio between the voltage measured at each recording electrode and the current injected at the stimulation contact. The result of the measurements is a matrix of 21x21 transimpedances. Stimulation current cannot be perceived by a patient thus making TIM measurements a non-invasive and painless procedure. The test duration is only 2-3 minutes

Depth sounding and spectroscopy

Intervention Type PROCEDURE

Depth sounding and spectroscopy are based on the matrixes obtained after TIM imaging. Deep sounding measures the capacitances throughout the electrode array whereas spectroscopy determines the phase of every transimpedance value. These tests take 10 to 15 minutes together. The stimulation intensity used by depth sounding technique can be perceived by a patient. If it is considered as unpleasant, the test will be stopped.

Cone Beam Computer Tomography

Intervention Type PROCEDURE

CBCT is a routine postoperative assessment after CI, non-invasive and painless for patients.

Interventions

Learn about the drugs, procedures, or behavioral strategies being tested and how they are applied within this trial.

Transimedance Matrix measurements

TIM measurements are based on cochlear implant back-telemetry function. Each electrode contact is stimulated in monopolar mode. Transimpedance is represented by the ratio between the voltage measured at each recording electrode and the current injected at the stimulation contact. The result of the measurements is a matrix of 21x21 transimpedances. Stimulation current cannot be perceived by a patient thus making TIM measurements a non-invasive and painless procedure. The test duration is only 2-3 minutes

Intervention Type PROCEDURE

Depth sounding and spectroscopy

Depth sounding and spectroscopy are based on the matrixes obtained after TIM imaging. Deep sounding measures the capacitances throughout the electrode array whereas spectroscopy determines the phase of every transimpedance value. These tests take 10 to 15 minutes together. The stimulation intensity used by depth sounding technique can be perceived by a patient. If it is considered as unpleasant, the test will be stopped.

Intervention Type PROCEDURE

Cone Beam Computer Tomography

CBCT is a routine postoperative assessment after CI, non-invasive and painless for patients.

Intervention Type PROCEDURE

Other Intervention Names

Discover alternative or legacy names that may be used to describe the listed interventions across different sources.

TIM measurements CBCT

Eligibility Criteria

Check the participation requirements, including inclusion and exclusion rules, age limits, and whether healthy volunteers are accepted.

Inclusion Criteria

Group with long-term implantation:

* Age18 years or older
* Affiliation to the French social security
* Signed and dated informed consent form
* Users of uni or bilateral cochlear implants for more than 6 months (CI24CA, CI422, CI512, CI522, CI532, CI612; CI622; CI632), in primo-implantation or reimplantation, with more than 18 electrodes active
* Postoperation CBCT imaging results available

Recently-implanted group:

* Age18 years or older
* Affiliation to the French social security
* Signed and dated informed consent form
* Indication for CI622 or CI632 cochlear implants
* Postoperation CBCT imaging results available

Exclusion Criteria

* Vulnerable individuals (minors, adults protected in accordance to the French Public Health code, patients deprived of liberty by court decision)
* Daily usage of the cochlear implant for less than 4 hours or weekly usage for less than 5 days
* Failure or disfunction of the cochlear implant
Minimum Eligible Age

18 Years

Maximum Eligible Age

120 Years

Eligible Sex

ALL

Accepts Healthy Volunteers

No

Sponsors

Meet the organizations funding or collaborating on the study and learn about their roles.

University Hospital, Montpellier

OTHER

Sponsor Role lead

Responsible Party

Identify the individual or organization who holds primary responsibility for the study information submitted to regulators.

Responsibility Role SPONSOR

Locations

Explore where the study is taking place and check the recruitment status at each participating site.

University Hospital Montpellier

Montpellier, , France

Site Status RECRUITING

Countries

Review the countries where the study has at least one active or historical site.

France

Central Contacts

Reach out to these primary contacts for questions about participation or study logistics.

Venail Frederic, MD, PhD

Role: CONTACT

+33467336890

Facility Contacts

Find local site contact details for specific facilities participating in the trial.

Frédéric Venail

Role: primary

Other Identifiers

Review additional registry numbers or institutional identifiers associated with this trial.

RECHMPL20_0666

Identifier Type: -

Identifier Source: org_study_id

More Related Trials

Additional clinical trials that may be relevant based on similarity analysis.