Hearing LossFunCoSyNCT06556160
Fundamental and Clinical Study of Cochlear Synaptopathy
A study testing near field recording of human auditory nerve activity during retro sigmoid approach with contact electrode in people with Hearing Loss, run by CHU de Reims at 1 site in France.
Trial summary
In humans, surface electrophysiological recording of the cochlear nerve in response to a sound stimulus provides information about the integrity and function of synapses (synaptic transmission) and nerve fibre function. However, this information remains global. Read more about this study
- Who is it for?
- Ages 18 to 70 years
- Conditions the study is for
- Hearing Loss
- What is being tested?
- near field recording of human auditory nerve activity during retro sigmoid approach with contact electrode
- Type of treatment
- Surgery or procedure
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 19 participants
- Where
- 1 siteFrance
- Study dates
- 21 Mar 2023to 4 Nov 2025
- Phase
- Interventional
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 70 years
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Patients with normal hearing will be included:
- male or female
- over 18 and up to 70 years of age
- normal otoscopic examination
- due to undergo surgery on the cerebellopontine angle (microvascular decompression).
- free of neuro-sensory deafness, defined by mean hearing thresholds of less than or equal to 20 dB HL in pure tone audiometry in air conduction bilaterally on the side of the ear operated on and on the non-operated side from 0.25 to 8 kHz
Show all 15Show fewer
- affiliated to a social security scheme
- have read the information note describing the study and have agreed in writing to take part by signing the informed consent form.
- Patients with a hearing impairment will be included:
- male or female
- over 18 and up to 70 years of age
- normal otoscopic examination
- due to undergo surgery on the cerebellopontine angle (microvascular decompression).
- have a sensorineural hearing loss defined by hearing thresholds of 20 dB HL or better from 0.25 to 2 kHz and from 20 dB HL excluded to 55 dB HL at frequencies above 2 kHz.
- have read the information note describing the study and have agreed in writing to take part by signing the informed consent form.
Who cannot join
- Patients will be excluded from the study for whom the auditory nerve is not accessible during surgery, in particular because of complete tumour invasion of the cochlear nerve (stage III and IV neuroma, advanced meningioma) or because of a particular anatomical feature not identified during the preoperative examination, making it impossible to expose the nerve for recordings (protrusion of the posterior surface of the rock).
Trial locations and contacts
1 site in 1 country.
About this study
Official title: Basic and Clinical Studies of Cochlear Synaptopathy
In humans, surface electrophysiological recording of the cochlear nerve in response to a sound stimulus provides information about the integrity and function of synapses (synaptic transmission) and nerve fibre function. However, this information remains global. The investigators have preliminary data showing that it is possible to extract and characterise the functional properties of nerve fibres during otoneurosurgery in humans, and therefore to isolate the neuronal sub-populations mentioned above more precisely than is currently possible. The use of these electrophysiological data from near-field recordings, i.e. in contact with the nerve, will enable the design and improvement of a mathematical model of the human cochlea. This model will provide access to the individual responses of each nerve fibre and fill the current gap in knowledge between the functioning of these fibres and global surface recordings.
Read the detailed description
During functional surgery on the cerebellopontine angle, a ball electrode is placed on the human cochlear nerve to monitor hearing. Once the electrode is in place, clicks and random noise bands will be delivered in order to analyze the cochlear electrophysiological signal produced. Depending on the characteristics recorded, this signal can be used at a given frequency and intensity to identify the populations of auditory neurons mainly involved. Prior to surgery, each patient will have been examined by the audiologist in order to determine the auditory thresholds in silence and noise, in tone and in speech, to carry out the digit test and to perform an electrocochleography and distortion products. Each result analyzed will be the subject of a further analysis using the mathematic model of the human cochlea.
- Conditions
- Hearing Loss
- Being tested
- near field recording of human auditory nerve activity during retro sigmoid approach with contact electrode
- Keywords
- Hearing Loss, Deafness, Micro vascular decompression, otoneurosurgery, retrosigmoid approach
- Medical subject headings
- Hearing Loss, Deafness
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
near field recording of human auditory nerve activity during retro sigmoid approach with contact electrodeProcedure or surgery
During surgery using a retro-sigmoid approach in the cerebellopontine angle (microvascular decompression), near-field recording of human auditory nerve activity using a contact electrode is performed on patients with normal or impaired hearing threshold.
Each patient is explored preoperatively by hearing tests to search synaptopathie. During the surgery, stimuli are delivered.
| Study group | Role | What they receive |
|---|---|---|
| hearing impaired patients | Experimental | have a sensorineural hearing loss defined by hearing thresholds of 20 dB HL or better from 0.25 to 2 kHz and from 20 dB HL excluded to 55 dB HL at frequencies above 2 kHz. Receives: Procedure: near field recording of human auditory nerve activity during retro sigmoid approach with contact electrode |
| normal hearing patients | Active comparator | free of neuro-sensory deafness, defined by mean hearing thresholds of less than or equal to 20 dB HL in pure tone audiometry in air conduction bilaterally on the side of the ear operated on and on the non-operated side from 0.25 to 8 kHz Receives: Procedure: near field recording of human auditory nerve activity during retro sigmoid approach with contact electrode |
What is being measured
The primary outcome is the main question the study is designed to answer.
In response to a stimulus, the neurophonic potential recorded in the form of a wave called PSTR will be characterised patients defined as normo and hearing loss based on preoperative audiometric tests
During ponto cerebellum retro sigmoide surgery. In response to a stimulus, the neurophonic potential recorded in the form of a wave called PSTR will be characterised patients defined as normo and hearing loss based on preoperative audiometric tests by the following indices:- the amplitude of the peak- the amplitude of the plateau- the peak to plateau ratio- the time constant for the rapid decay of the peak- the time constant for the slow decay of the peak.
Measured: At 48 months
Compare the amplitude and spectrum of global evoked auditory nerve activity with basic stimuli between patients defined as normo and hearing loss based on preoperative audiometric tests
During ponto cerebellum retro sigmoide surgeryelectrocochleography and distortion products.
Measured: At 48 months
Secondary outcomes (1)
compare the primary objective with the results obtained with a mathematical model of the human cochlea in order to improve the responses of our model.
During ponto cerebellum retro sigmoide surgery
Measured: At 48 months
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted15 Aug 2024
- Study start21 Mar 2023
- Primary completion16 Jul 2025
- Study completion4 Nov 2025
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Hearing LossStudies of the same condition, open and under way.
- More trials run by CHU de ReimsThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Basic science
- Allocation
- Non-randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Enrolment
- 19 participants (actual)
Sponsor and investigators
- Lead sponsor
- CHU de Reims
- Sponsor type
- University, hospital or other
- Responsible party
- Sponsor
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT06556160
- Sponsor's protocol ID
- PO23045
- Acronym
- FunCoSy
- Status last verified
- Dec 2025
- First submitted
- 17 Aug 2023
- Last updated
- 18 Dec 2025
- Results posted
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
Study at a glance
From the registry record, last updated by the sponsor on 18 Dec 2025. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Basic and Clinical Studies of Cochlear Synaptopathy
- ClinicalTrials.gov ID
- NCT06556160
- Acronym / sponsor ID
- FunCoSy / PO23045
- Conditions
- Hearing Loss
- Keywords
- Hearing Loss, Deafness, Micro vascular decompression, otoneurosurgery, retrosigmoid approach
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 19 participants (actual)
- Lead sponsor
- CHU de ReimsUniversity, hospital or other
- Study start
- 21 Mar 2023 (actual)
- Primary completion
- 16 Jul 2025 (actual)
- Study completion
- 4 Nov 2025 (actual)
- First posted
- 15 Aug 2024 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
In humans, surface electrophysiological recording of the cochlear nerve in response to a sound stimulus provides information about the integrity and function of synapses (synaptic transmission) and nerve fibre function. However, this information remains global. The investigators have preliminary data showing that it is possible to extract and characterise the functional properties of nerve fibres during otoneurosurgery in humans, and therefore to isolate the neuronal sub-populations mentioned above more precisely than is currently possible. The use of these electrophysiological data from near-field recordings, i.e. in contact with the nerve, will enable the design and improvement of a mathematical model of the human cochlea. This model will provide access to the individual responses of each nerve fibre and fill the current gap in knowledge between the functioning of these fibres and global surface recordings.
Detailed description
During functional surgery on the cerebellopontine angle, a ball electrode is placed on the human cochlear nerve to monitor hearing. Once the electrode is in place, clicks and random noise bands will be delivered in order to analyze the cochlear electrophysiological signal produced. Depending on the characteristics recorded, this signal can be used at a given frequency and intensity to identify the populations of auditory neurons mainly involved. Prior to surgery, each patient will have been examined by the audiologist in order to determine the auditory thresholds in silence and noise, in tone and in speech, to carry out the digit test and to perform an electrocochleography and distortion products. Each result analyzed will be the subject of a further analysis using the mathematic model of the human cochlea.
Study design
- Primary purpose
- Basic science
- Allocation
- Non-randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| hearing impaired patients | Experimental | Procedure: near field recording of human auditory nerve activity during retro sigmoid approach with contact electrodehave a sensorineural hearing loss defined by hearing thresholds of 20 dB HL or better from 0.25 to 2 kHz and from 20 dB HL excluded to 55 dB HL at frequencies above 2 kHz. |
| normal hearing patients | Active comparator | Procedure: near field recording of human auditory nerve activity during retro sigmoid approach with contact electrodefree of neuro-sensory deafness, defined by mean hearing thresholds of less than or equal to 20 dB HL in pure tone audiometry in air conduction bilaterally on the side of the ear operated on and on the non-operated side from 0.25 to 8 kHz |
Who may qualify
- Ages
- 18 to 70 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (15 listed)
- male or female
- over 18 and up to 70 years of age
- normal otoscopic examination
- due to undergo surgery on the cerebellopontine angle (microvascular decompression).
- free of neuro-sensory deafness, defined by mean hearing thresholds of less than or equal to 20 dB HL in pure tone audiometry in air conduction bilaterally on the side of the ear operated on and on the non-operated side from 0.25 to 8 kHz
Key exclusion criteria (1 listed)
- Patients will be excluded from the study for whom the auditory nerve is not accessible during surgery, in particular because of complete tumour invasion of the cochlear nerve (stage III and IV neuroma, advanced meningioma) or because of a particular anatomical feature not identified during the preoperative examination, making it impossible to expose the nerve for recordings (protrusion of the posterior surface of the rock).
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| near field recording of human auditory nerve activity during retro sigmoid approach with contact electrodeDuring surgery using a retro-sigmoid approach in the cerebellopontine angle (microvascular decompression), near-field recording of human auditory nerve activity using a contact electrode is performed on patients with normal or impaired hearing threshold. Each patient is explored preoperatively by hearing tests to search synaptopathie. During the surgery, stimuli are delivered. | Procedure or surgery | hearing impaired patients, normal hearing patients |
Primary outcome
In response to a stimulus, the neurophonic potential recorded in the form of a wave called PSTR will be characterised patients defined as normo and hearing loss based on preoperative audiometric tests
Time frame: At 48 months
During ponto cerebellum retro sigmoide surgery. In response to a stimulus, the neurophonic potential recorded in the form of a wave called PSTR will be characterised patients defined as normo and hearing loss based on preoperative audiometric tests by the following indices:- the amplitude of the peak- the amplitude of the plateau- the peak to plateau ratio- the time constant for the rapid decay of the peak- the time constant for the slow decay of the peak.
Compare the amplitude and spectrum of global evoked auditory nerve activity with basic stimuli between patients defined as normo and hearing loss based on preoperative audiometric tests
Time frame: At 48 months
During ponto cerebellum retro sigmoide surgeryelectrocochleography and distortion products.
1 secondary outcome
compare the primary objective with the results obtained with a mathematical model of the human cochlea in order to improve the responses of our model.
Time frame: At 48 months
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 18 Dec 2025.
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
The record lists no contact. Use the official record to reach the sponsor.
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing near field recording of human auditory nerve activity during retro sigmoid approach with contact electrode in people with Hearing Loss, run by CHU de Reims at 1 site in France.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 15 inclusion and 1 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 18 Dec 2025. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in France. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
In response to a stimulus, the neurophonic potential recorded in the form of a wave called PSTR will be characterised patients defined as normo and hearing loss based on preoperative audiometric tests (time frame: At 48 months). The study lists 2 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 18 Dec 2025.