Inclusion Criteria:

• Age: ≥ 18 years of age.
• Normal to moderate SNHL (≤ 70 dB HL; based on PTA of 0.5, 1 and 2 kHz) and WRS ≥ 75% in the ear to be implanted.
• Asymmetric or unilateral subjective tonal tinnitus
• Subjectively severe tinnitus present for at least 6 months, but not longer than 12 years; it is permissible to include people who have had intermittent or constant tinnitus longer than 12 years as long as it was not perceived as severe longer than 12 years.
• Tinnitus that is disruptive by at least two of the three criteria:
  • THI in the severe range (≥ 56/100);
  • TFI in the severe range (≥ 52/100);
  • Tinnitus VAS-A or Tinnitus VAS-L ≥ 50/100.
• Tinnitus that is intractable, and has not been ameliorated by conventional measures such as a hearing aid or masking, when such interventions are potentially clinically indicated (e.g., it is not expected that people with minimal or no hearing loss would trial a conventional hearing aid)
• MRI of the head that does not reveal any anatomical or structural abnormalities of the inner ear, cochlear nerve, or brainstem that would negatively impact response to study intervention (e.g., vestibular schwannoma)
• Temporal bone CT that does not reveal any major anatomical or structural abnormalities that would negatively impact response to study intervention.
• Participants must be able to read, understand, and provide informed consent to participate in the trial.
• Participants must be willing and anticipate being able to return for study procedures and follow up visits.
• Participants must have completed participation in the study entitled “Cochlear Promontory Stimulation for Treatment of Tinnitus: Towards Developing an Implantable Device” (IRB 17-004832) at Mayo Clinic.

Exclusion Criteria:

• Age: < 18 years of age.
• Subjectively severe tinnitus present less than 6 months or longer than 12 years; it is permissible to include people who have had intermittent or constant tinnitus longer than 12 years as long as it was not perceived as severe longer than 12 years.
• History of brain or major ear surgery.
• History of brain or temporal bone tumor(s).
• Recurrent ear infections within the last year.
• Prior major head trauma, defined for the purposes of this study as head trauma that results in sudden injury that causes damage to the brain and results in lasting cognitive impairment.
• Ongoing clinical diagnosis of depression or anxiety; for the purposes of this study, it is permissible to include people who: 1. have a past history of clinically diagnosed depression or anxiety that is no longer currently active; or 2. people who have depressive or anxious symptoms that are thought to primarily result from severe tinnitus
• Presence of clinically significant depressive or anxiety symptoms determined by screening. using the GAD-7, PHQ-8, and SHIA questionnaires.
  • GAD-7 score > 9 (indicates clinically significant anxiety);
  • PHQ-8 score > 9 (indicates clinically significant depression);
  • SHAI score > 25 (hypochondriacal level illness anxiety).
• Currently taking regularly scheduled antidepressant, anxiolytic, antipsychotic or antiepileptic medications, or other neuromodulatory agents; for this study, it is permissible to include people who use such medications at lower doses as a sleep aid or for people who intermittently use such medications for situational anxiety (e.g., Ativan before airplane travel).
• Active use of other tinnitus treatments; for the purposes of this study it is permissible to include people who prefer to use a hearing aid to amplify ipsilateral hearing loss.
• Known pregnancy at time of surgery.
• Any medical condition, including mental illness or substance abuse, deemed by the PI to likely interfere with a patient’s ability to sign informed consent, cooperate and participate in the study, or interfere with the interpretation of the results.

Eligibility last updated 5/18/22. Questions regarding updates should be directed to the study team contact.