A Pivotal Study to Evaluate the Efficacy and Safety of a Totally Implantable Cochlear Implant (TICI) System in Adults

Inclusion Criteria: * Individuals aged 18 years and older at time of consent. * Clinically established post-linguistic moderately severe to profound sensorineural hearing loss (PTA4 of \>55 dB HL), in the ear to be implanted. * Meets local candidacy criteria for cochlear implantation. * Compromised functional hearing with a hearing aid in the ear to be implanted, as determined by the investigator. * Willing to undergo unilateral cochlear implantation. * Candidate is a fluent speaker in the language used to assess speech perception performance as determined by the investigator * Direct access to a compatible Smart Phone. * Willing and able to provide written informed consent. Exclusion Criteria: * Prior cochlear implantation, in either ear, or medical plan for cochlear implantation during the clinical investigation, contralateral to the ear to be implanted. * Candidates with single-sided deafness as determined by the investigator. * Intra-axial (within-the-brain) lesions or deafness due to lesions of the acoustic nerve affecting the ear to be implanted. * Middle ear infection (including acute otitis media, chronic otitis media, suppurative otitis media, or serous drainage) in the ear to be implanted either at the time of surgery or within 3 months prior to enrolment. * Presence of a tympanic membrane perforation or a history of otologic surgery within 3 months prior to enrolment, in the ear to be implanted. * Previously reported diagnosis of auditory neuropathy, in the ear …