Feasibility of the Mi2000 Totally Implantable Cochlear Implant in Severely to Profoundly Deaf Adults.

Cochlear implants (CI) provide a large majority of recipients with a significant degree of speech understanding. However, CI systems rely on external parts, namely Behind-the-Ear (BTE) audio processors with coils or single-unit processors to function. This can have several disadvantages: for instance, the hardware is exposed to external trauma and to the effects of head movement and gravity. The device is also put at risk by humid, dusty, or dirty conditions as well as by physical activities that lead to water exposure such as swimming or sports in general (e.g. perspiration).

In addition, some patients are concerned with the cosmetic appearance of the external parts which are visible (more so than modern behind-the-ear hearing aids), something that may not be desirable to many potential candidates.

This clinical investigation aims to collect data on the use of the Mi2000 system, a totally implantable cochlear implant system, for the first time in human subjects.

Inclusion criteria

• Minimum age of eighteen (18) years at time of enrolment
• Bilateral sensorineural hearing loss with no or limited benefit from a hearing aid (>70 dB HL PTA4)
• Post-lingual onset of deafness
• No or limited benefit from hearing aids for less than 10 years.
• A maximum score of 50% on a monosyllables test in the language of the test centre in the ear to be implanted
• General health condition, psychological and emotional condition deemed compatible with the treatment and tests performed in this study and realistic expectations, as deemed appropriate by the implanting surgeon/implant board
• Fluency in the test language with excellent proficiency, as appropriate to perform speech testing
• Evidence of up-to-date vaccinations against meningitis, as per recommendations by the applicable national body
• Signed and dated informed consent before the start of any study-specific procedure

Exclusion criteria

• Lack of compliance with any inclusion criterion
• Previously having received an implant on the location chosen for placing the cochlear implant
• Having received a hearing implant from another manufacturer than MED-EL on the contralateral ear
• Pre-existing condition known to necessitate MRI scans after implantation of the Mi2000
• Women being pregnant or nursing
• Women of child-bearing age not reporting to use effective contraception
• Contraindication to surgery in the middle and inner ear
• Contraindication to general anaesthesia
• Cochlear malformations, ossification or other obliteration of the cochlea, history of meningitis preventing placement of the electrode array, as confirmed by medical examination
• Acute cholesteatoma
• Acute external or middle ear infections
• Perforated tympanic membrane
• Known intolerance to any of the materials used for the implant or accessories
• Non-functional auditory nerve and/or upper auditory pathway including a history of vestibular schwannoma
• Factors preventing appropriate placement of the stimulator housing and the microphone, including fixation with screws, in the bone of the skull
• Unstable Meniere's disease, Auditory Neuropathy, Epilepsy not responding to treatment
• Unrealistic expectations of the subject
• Permanent inability and/or unwillingness to participation in post-operative care and rehabilitation
• Known intellectual disability and/or psychological diseases
• Participation in other pharmacological clinical trials within four weeks prior to enrolment