Wide Frequency Band Test of Hearing in Veterans
Condition: Hearing Loss, Sensorineural; Hearing Loss, Conductive; Hearing Loss, Mixed Conductive-Sensorineural; Otosclerosis; Tympanic Membrane Perforation; Otitis Media With Effusion; Cholesteatoma
MeSH terms: Hearing Loss; Deafness; Otitis Media; Otitis Media with Effusion; Hearing Loss, Sensorineural; Otosclerosis; Tympanic Membrane Perforation; Hearing Loss, Conductive; Hearing Loss, Mixed Conductive-Sensorineural; Cholesteatoma
Study type: Observational

Summary: 
      The accurate assessment of auditory status is critical for planning treatment for Veterans
      with hearing loss to include medical and audiological management. Current physiologic tests
      of auditory function in the standard clinical audiological test battery for Veterans have
      limited sensitivity in detecting some middle-ear disorders, and do not include a direct test
      of cochlear function. Recent studies have shown promise for new wide-bandwidth (WB) tests of
      absorbance for improved sensitivity in the assessment of middle-ear function including
      acoustic reflex testing. The addition of WB tests of cochlear function included in the WB
      test battery provides an opportunity to improve audiological diagnosis of a range of hearing
      disorders in Veterans. The automation provided by the WB test battery could provide
      additional benefits in reducing the duration of the evaluation, leaving more time for
      evaluation of test findings and counseling. Results from this study may lead to the
      improvement of audiological care for Veterans with hearing loss.
    

Detailed description: 
      The goal of this research is to evaluate a comprehensive test battery of new wide-bandwidth,
      i.e., wideband (WB), acoustical tests of auditory function in the differential diagnosis of
      middle ear, cochlear and neural pathologies in a population of Veterans. WB tests refer to
      ear canal tests using sound responses measured from 0.2 kilohertz (kHz) to frequencies as
      high as 8 kHz, a bandwidth that is critical for speech perception. There will be tests in the
      battery for middle-ear assessment using power absorption, cochlear assessment using
      otoacoustic emissions (OAEs) and the acoustic stapedius reflex (ASR) using middle ear power
      absorption. Results will be compared with a standard single-frequency clinical immittance
      test battery routinely used in the assessment of auditory function in Veterans. Aim 1 seeks
      to evaluate the accuracy of the WB test battery in the differential diagnosis of middle-ear
      pathology and related conductive hearing loss by comparing the sensitivity and specificity of
      the WB battery to the traditional immittance battery for the following disorders common in
      Veterans: tympanic membrane perforation, serous otitis media, cholesteatoma, and
      otosclerosis. Aim 2 seeks to modify a WB ASR test to provide automatic detection of the ASR
      threshold for comparison with the traditional single-frequency ASR threshold. Aim 3 seeks to
      validate the use of Transient-evoked otoacoustic emission (TEOAE) and spontaneous otoacoustic
      emissions (SOAEs)tests in Veterans to assess cochlear status, and evaluate their test
      performance in classifying ears with normal hearing and sensorineural hearing loss. Finally,
      Aim 4 seeks to compare the diagnostic accuracy of the full WB test battery with the full
      single-frequency admittance test battery to detect any type of hearing loss including
      sensorineural, conductive and mixed. The hypothesis is that the WB test battery is more
      accurate than the traditional immittance test battery in identifying ears with normal
      auditory status and ears with a range of risks for auditory pathology.

      Methods:

      Subjects- Human subjects will be recruited for this study who have had a hearing evaluation
      from the VA Audiology Service at the Portland VA Medical Center and the H. Quillen VA Medical
      Center. These subjects will respond to flyers or be contacted from an IRB-approved human
      subject volunteer registry. Additional details regarding recruitment and selection criteria
      may be found in the next sections of the protocol. The investigators will recruit
      approximately equal numbers of subjects, with a total of 640. Data will be acquired at the
      two sites from a total of 190 adult subjects with normal hearing and 180 adult subjects with
      sensorineural hearing loss. These subjects will be recruited from three age groups: 20-39
      years, 40-59 years and 60-79 years for age comparisons of normative middle-ear data. Data
      will also be acquired at both sites from 250 adult subjects with middle-ear disorders and/or
      conductive hearing loss from ages 20-89 years. Of this latter group, the investigators plan
      to enroll 50 subjects with tympanic membrane perforation, 50 subjects with serous otitis
      media, 50 subjects with cholesteatoma, 50 subjects with otosclerosis, and 50 subjects with
      unspecified middle-ear disorders. The investigators expect that approximately 20 subjects
      (from all groups, normal hearing, sensorineural hearing loss, and middle-ear disorders) will
      be lost as screen failures or will drop from the study, and thus, the investigators will
      recruit an additional 20 subjects to replace these. This brings the total planned number of
      subjects recruited for study to 640.

      Testing- All subjects will receive the same clinical and WB test battery. Each subject will
      be tested in one laboratory visit. Subjects will be enrolled in this study that upon
      otoscopic inspection of their ear canals, have no active drainage from the ears, and have ear
      canals free of cerumen (wax) impaction, bilaterally. Subjects who are found to have draining
      ears or cerumen impaction will be referred for treatment. These individuals may be enrolled
      in the study following successful treatment for their conditions. All subjects will have a
      standard pure-tone air- and bone-conduction audiogram while comfortably seated in a
      sound-treated booth. Standard insert earphones and a bone-conduction vibrator will be used to
      present the sound stimuli. Next, speech audiometry will be completed and the speech reception
      thresholds, uncomfortable loudness test for speech, and speech recognition scores will be
      obtained. Then the subjects will have a standard immittance test battery consisting of a
      tympanogram and acoustic reflex threshold testing. Stimuli will not exceed a level of 100
      decibels hearing level (dB HL). Finally, the wideband test battery will be performed with
      adults seated comfortably in a sound-treated booth. A small probe with a soft rubber tip will
      be inserted in the subject's ear canal, and the subject will be asked to remain quiet while
      sounds are presented to an ear via sound sources within the probe. Responses will be measured
      using a miniature microphone within the probe. The tests in the wideband battery are similar
      to the clinical admittance battery and include ambient absorbance, absorbance tympanometry
      and acoustic reflex threshold. The otoacoustic emission testing is a separate measurement of
      inner ear function typically conducted in the clinic using different equipment.
    

Observational model: Case-Control
Time perspective: Cross-Sectional
Sampling method: Non-Probability Sample
Study population: 
        Veterans will be recruited for this study who have had a hearing evaluation from the VA
        Audiology Service at the Portland VA Medical Center and the H. Quillen VA Medical Center.
        We may also recruit from approved subject registries at each study site, and from those who
        respond to approved fliers posted at the each site.
      
Keywords: Ear, Middle; Ear, Inner; Audiometry; Acoustic impedance tests