Cochlear Promontory Stimulation for Treatment of Tinnitus

Not Applicable

Completed

Conditions: Tinnitus

Registration Number: NCT03759834

Lead Sponsor: Mayo Clinic

Brief Summary: Tinnitus is the perception of sound when no external noise is present. The Center for Disease Control (CDC) estimates over 50 million - nearly 15% of the general public -experience some form of tinnitus. Roughly 20 million people struggle with burdensome chronic tinnitus, with 2 million experiencing extreme and debilitating symptoms.

The 2014 Clinical Practice Guideline on tinnitus from the American Academy of Otolaryngology - Head and Neck Surgery summarized the existing state of tinnitus management by stating "A cure for primary tinnitus does not yet exist, and despite claims to the contrary, no method has been proven to provide long-term suppression of tinnitus."

The purpose of this study is to look at the safety and efficacy of cochlear promontory stimulation in the short term relief of tinnitus. The secondary goal of the study is to determine the optimum region(s) of the cochlear promontory in planning for an implantable electrical device for long term tinnitus suppression.

Detailed Description: Candidate subjects will undergo a temporal bone Computed Tomography (CT) scan, contrast enhanced head Magnetic Resonance Imaging (MRI), audiogram with immittance testing, pitch and level matching of tinnitus, Distortion Product Otoacoustic Emissions (DPOAE) and Auditory Brainstem Response (ABR) testing prior to promontory stimulation. Head MRI, DPOAE, audiogram and immittance testing are considered clinically routine for assessment of asymmetric tinnitus. Temporal bone CT, ABR, tinnitus pitch, level matching, masking levels and residual inhibition testing are not standard clinical assessments for asymmetric tinnitus. In addition, subjects will complete the Tinnitus Handicap Inventory (THI), Tinnitus Functional Index (TFI) and Visual Analog Scale (VAS) questionnaires three separate times within the week prior to promontory stimulation testing. Additional testing for comorbid anxiety and depressive conditions will be a screening Generalized Anxiety Disorder (GAD7), Patient Health Questionnaire (PHQ8), and short Health Anxiety Inventory (HAI-S). The NEO Personality Inventory (NEO PI) will be administered to provide baseline information. The initial session of promontory stimulation will define optimal stimulation parameters (i.e., location, current level, pulse-width, phase polarity), where maximal tinnitus suppression occurs with minimal or no auditory percept. After these parameters are established, the patient will complete the THI, TFI, and VAS immediately prior to stimulation, during stimulation, and following completion of stimulation at 10-minutes, 1-hour, 24-hours, 48-hours, and 1-week following completion of stimulation. In addition, pitch and level matching of tinnitus will be completed immediately upon completion of each promontory stimulation session. Each patient will undergo three successive treatments separated by 1-week. Prior to each treatment, the patient will receive an audiogram and DPOAE testing to document interval safety. At the conclusion of the study, subjects will be asked about their willingness to undergo surgical implantation of a device capable of long-term scheduled or on-demand electrical stimulation for tinnitus suppression

Recruitment & Eligibility

Status: COMPLETED

Sex: All

Target Recruitment: 25

Inclusion Criteria

Normal to moderate sensorineural hearing loss (based on pure tone audiometry (PTA) of 500, 1000 and 2000 Hz) and a word recognition score equal to or greater than 60%
Asymmetric or unilateral subjective tonal tinnitus
Tinnitus that is disruptive
1. Determined by THI score (in the severe range i.e. ≥56/100)
2. TFI (in the severe range i.e. ≥52/100)
3. Tinnitus VAS (≥ 5/10 )
Tinnitus that is intractable, and has not been ameliorated by conventional measures such as a hearing aid or masking
Normal contrast-enhanced MRI of the head

Exclusion Criteria

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
Prior major head trauma
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

a. Determined by screening using the GAD 7, PHQ8, and HAI-S
- GAD7 > 9 (indicates clinically significant anxiety)
- PHQ > 9 (indicates clinically significant depression)
- HAI-S > 25 (hypochondriacal level illness anxiety)
Inability to assess, continue or complete trial
Currently on regularly scheduled antidepressants, anxiolytics or antipsychotics; 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

Study & Design

Study Type: INTERVENTIONAL

Study Design: SINGLE_GROUP

Primary Outcome Measures

Name	Time	Method
Change in Short Term Relief of Tinnitus as Measured by the Tinnitus Handicap Inventory	Baseline to 4 months	The Tinnitus Handicap Inventory (THI) has 25 questions with possible answers of Yes (4 points), Sometimes (2 points), and No (0 points). Scores categories are (1-16: Slight or no handicap - Grade 1), (18-36: Mild handicap - Grade 2), (38-56: Moderate handicap - Grade 3), (58-76: Severe handicap - Grade 4), (78-100: Catastrophic handicap - Grade 5). Total score ranges from 0 to 100 with higher scores indicating a worse outcome.

Secondary Outcome Measures

Name	Time	Method
Optimal Location of Tinnitus Relief	Immediately after electrical stimulation procedure (approximately 1 min after stimulation)	Location on the cochlear promontory where highest perceived benefit from electrical stimulation
Auditory Feedback	Immediately after electrical stimulation procedure (approximately 1 min after stimulation)	The number of subjects that reported hearing the electrical stimulus (if at all)
Tactile Feedback	Immediately after electrical stimulation procedure (approximately 1 min after stimulation)	The number of subjects that reported feeling the electrical stimulus (if at all)
Change in Short Term Relief of Tinnitus as Measured by the Tinnitus Functional Index	Baseline to 4 months	The Tinnitus Functional Index (TFI) contains eight subscales (domains), of which seven contain 3 items and one contains 4. The possible responses for each item range from 0 (did not interfere) to 10 (completely interfered). The total score is transformed to a scale ranging from 0 (no interference) to 100 (completely interfered with activities).
Change in Short Term Relief of Tinnitus as Measured by the Visual Analog Scale	Baseline to 4 months	The Visual Analog Scale (VAS) for Numeric Pain Distress was used for this outcome. The VAS is a 11-item questionnaire assessing pain. Using a scale of 0 (no pain) and 10 (unbearable pain). Total scores range from 0 - 110, lower scores indicating lower pain and higher scores indicating greater pain.