Implantation of the Cochlear® Nucleus® System in Adults With Single-Sided Deafness

Inclusion criteria

• Ability to provide informed consent.
• Eighteen years-of-age or older at the time of implantation.
• Presence of single-sided deafness as follows:

• Poorer ear (ear to be implanted):

• severe to profound sensorineural hearing loss, defined as pure-tone thresholds 80 dB HL or greater for the frequencies 500, 1000, 2000, 3000, and 4000 Hz.
• Monosyllabic word understanding, as measured using the CNC Word Test at 60 dBA under earphones, less than or equal to 10%.
• Better ear (contralateral ear):

• Normal or near-normal hearing, defined as pure-tone thresholds no poorer than 30 dB HL at 250, 500, 1000, 2000, and 3000 Hz and no poorer than 40 dB HL at 4000 Hz.
• Monosyllabic word understanding, as measured using the CNC Word Test at 60 dBA under earphones, of greater than or equal to 90%.
• Duration of severe to profound sensorineural hearing loss of at least 6 months (to ensure stability of hearing loss) but no greater than 10 years.
• English spoken as a primary language.

Exclusion criteria

• Alleviation of tinnitus as the stated primary or sole motivation for seeking implantation by the subject and/or investigator.
• Actively using an implantable device in the poorer ear.
• Onset of severe to profound hearing loss < 6 years-of-age.
• Evidence of active middle-ear pathology based on otologic examination and/or immittance testing.
• Medical or psychological conditions that contraindicate undergoing surgery.
• Ossification or any other cochlear anomaly at the implant ear that might prevent complete insertion of the electrode array.
• Hearing loss of neural or central origin, including auditory neuropathy.
• Unrealistic expectations on the part of the subject regarding the possible benefits, risks, and limitations inherent to the surgical procedure and prosthetic device.
• Unwillingness and/or inability of the candidate to comply with all investigational requirements including, but not limited to, study protocol and surgical procedure, as determined by the investigator.