Comparison of Speech Understanding and Melodic Perception of Two Tonotopic Fitting Modalities With or Without Fine Structure in Newly Implanted Cochlear Patients: Randomized Double-blind Crossover Study.
Trial Snapshot
- Phase
- Not Applicable
- Status
- Completed
- Sponsor
- Enrollment
- 21
- Locations
- 2
- Primary Endpoint
- Speech recognition in noise
Study Overview
Brief Summary
Brief Summary:
Main objective:
Comparison of a tonotopy based fitting strategy (TFS) with fine structure coding to a tonotopy based fitting strategy without fine structure coding (TnoFS) for speech perception in noise.
Secondary objectives:
Comparison of TFS to TnoFS for the perception of musical elements (contour test).
Comparison of TFS to TnoFS for speech perception in quiet
Comparison of TFS to TnoFS for the qualitative preference for the listening of musical pieces.
Comparison of TFS to TnoFS for the melodic recognition
Detailed Description
Introduction: Cochlear implantation allows the rehabilitation of profound bilateral deafness, restoring speech perception and verbal communication when the traditional hearing aid no longer provides satisfactory hearing gain (Nimmons et al.).
A cochlear implant includes an electrode array and its functioning is based on the principle of cochlear tonotopy: each electrode encodes a frequency spectrum according to its position in the cochlea (high frequencies are assigned to the basal electrodes and low frequencies to the apical electrodes). The cochlear implant thus breaks down the frequency spectrum into a number of frequency bands via bandpass filters corresponding to the number of electrodes in the implant. During the fitting these bands can be modified by the audiologist.
The fitting software developed by the manufacturers proposed a default fitting with a lower limit between 100 and 250 Hz according to the brands and an upper limit of about 8500 Hz. The frequency bands assigned to each electrode follow a logarithmic scale with the high frequencies for the basal electrodes and the low frequencies for the apical electrodes. This distribution takes into account the number of active electrodes but does not take into account the anatomy and the natural cochlear tonotopy specific to each patient.
Several studies have analyzed the anatomical variations of the cochlear dimensions: size of the cochlea and the ratio between the contact surfaces of the electrodes with the cochlea are variable from one patient to another (Stakhovskaya O et al., P. Pelliccia et al.).
The insertion depth during surgery is also variable due to parameters related to the patients as well as to the operator, which seems to impact the understanding of speech in noise (Deep electrode insertion and sound coding in cochlear implants - Ingeborg Hochmair et al.).
Study Design
- Study Type
- Interventional
- Allocation
- Randomized
- Intervention Model
- Crossover
- Primary Purpose
- Other
- Masking
- Double (Participant, Investigator)
Masking Description
Double blind study: the patient and the investigator don't know the fitting.
Eligibility Criteria
- Ages
- 18 Years to — (Adult, Older Adult)
- Sex
- All
- Accepts Healthy Volunteers
- No
Inclusion Criteria
- •Adult patient (>= 18 years old) speaking French
- •Patient who fulfils the criteria for cochlear implantation
- •Total hearing loss for less than 5 years
Exclusion Criteria
- •retro-cochlear pathology: auditory neuropathy, vestibular schwannoma
- •patient with residual hearing < 60 dB HL at 250 Hz and < 80 dB HL at 500 Hz
Outcomes
Primary Outcomes
Speech recognition in noise
Time Frame: at 12 weeks post-activation
The speech recognition in noise is evaluated with syllabic list of 40 phonemes. The patient has to recognize 20 syllables. The phonemes are scored: each good answer is scored 1 yielding a total between 0 and 1 (or 0% and 100%). Signal-noise-ratios of 9, 6, 3 and 0 dB will be tested with speech at 65 dB SPL.
Secondary Outcomes
- Melodic recognition(at 12 weeks post-activation)
- Speech recognition in quiet(at 12 weeks post-activation)
- Melodic contour test(at 12 weeks post-activation)
- Qualitative measure of music(at 12 weeks post-activation)