Optimization of a Non-invasive Electrophysiological Method for Studying the Functionality of Auditory Nerve Fibers (ECOG)

University Hospital, Clermont-Ferrand

Status

Enrolling

Conditions

Without Hearing Disorders

Healthy Volunteer

Treatments

Diagnostic Test: Electrocochleography, electrophysiology thet for analyse the wave I generated by the auditory pathways

Study type

Interventional

Funder types

Other

Identifiers

NCT04198909

RBHP 2018 GIRAUDET

2018-A02525-50 (Other Identifier)

Details and patient eligibility

About

Acoustic overexposure can induced temporary or hearing loss. Usually hearing loss is associated with cochlear cell damages. Recently, a new pathological entity was described and called "hidden hearing loss". In animal model, the histopathology revealed a selective reduction in the number of auditory fibers, resulting in a decrease in the amplitude of wave I of the auditory brainstem response. Electrocochleography (Ecog) is a method for recording the electrical potentials of the cochlea (e.g. wave I). In clinical routine, Ecog is performed invasively with sedation or local anesthesia. Actually, a non invasive approach could be perform but it seems necessary to optimize this method and to define reference values in healthy volunteers.

Full description

The sound overexposure is a major cause of hearing disorders. The installation of hearing disorders can be temporary or permanent. Most of the time the investigators see a rise in hearing thresholds that can be accompanied by tinnitus. However, sometimes-hearing disorders aren't characterized by higher auditory threshold but by a complaint of understanding in noise. Two explanation are the either possible with a lesion at the peripheral level (sensory organ) or central lesion (auditory pathways). Peripheral damage is easily analysed by conventional tests such as the audiogram. Concerning the central lesions, through to the Electrocochleography, one sees a diminution of the wave I which corresponds to the nerve fiber injury. The wave I can more easily be analysed by the Electrocochleography method. This technique previously used an electrode deposited trans-tympanically in contact with the sensory organ. But, the evolution of a non-invasive technique is now available. However, several assemblies of the electrode are then possible without knowing the impact of these on the morphology of the wave I. Moreover, no normative values are also referenced in the literature on the population without hearing problems. It's in this context that clinical study is carried out in order to optimize the technique on the assembly of the electrode and the acoustic stimulation delivered. After this analyses and obtaining an optimal technique it's envisaged to study the morphology of the wave I in healthy volunteers aged 18-25 years. A pre-inclusion visit will verify the volunteers doesn't have a hearing disorders through a questionnaire, otoscopy, tympanometry and audiometry. Then two steps will be realized. The first is to evaluate the morphology of wave I according to assembly of electrode and acoustic stimulation delivered (machine calibration or calibration in the external auditory canal). The second step will provide normative values for people 18-25 years old who aren't hearing-impaired. Volunteers will have the choice to participate in one or both stages. The aim is to obtain wave I reference values for Electrocochleography technique. The secondary objectives are to analyse the impact of the assembly of the electrode and the adaptation of the acoustic stimulation presented.

Enrollment

430 estimated patients

Sex

All

Ages

18 to 55 years old

Volunteers

Accepts Healthy Volunteers

Inclusion criteria

Between 18 and 55 years old
be affiliated to a social security system
understand (oral and written) of the French language
be a qualified hearing with normal tympanogram and audiogram

Exclusion criteria

have a complaint of hearing
have a exposure to noise (professional and/or activities)
refusal to participate in the study
have ear infections and/or ENT medical history
have cardiovascular, metabolic, neurological and psychiatric desease
being a protected person
healthy volunteer who has received compensation equal to or greader than 4500€ in clinical study