& Continuing Education Courses
Sponsored by: Jordan Hearing and Balance, LLC South Jordan Utah
Lynn S. Alvord PhD
Tests for Hearing
Following are brief explanations of the various tests for hearing.
Pure Tone Audiometry – A test with earphones or ear inserts finding the lowest intensity (threshold) the patient can hear and respond to pure tones. Can also be tested using bone conduction, which by-passes the outer and middle ear.
Purpose – Determines the degree of hearing loss at various test frequencies. Good for determining diagnosis of hearing loss type, as well as degree of hearing loss.
Patient participation – Patient indicates each time he/she hears the sound, even if very low volume.
Speech Audiometry – Uses earphones, ear inserts or bone conducted sound to determine lowest intensity the patient can hear and respond to speech as delivered live by the tester or by CD, tape, or computer generated speech.
Purpose - Finds threshold (lowest level speech is heard) and/or determines clarity of speech in a percentage value (word recognitions score).
Patient Participation – Patient must repeat back words.
Tympanogram - Takes measurements of ear canal, ear drum and middle ear as well as certain reflexes.
Purpose – Assesses ear drum, middle ear pressure or fluid (as in ear infections), whether tubes are in and working, whether certain fistulas are present, etc. Also measures the status of inner ear reflexes for various purposes such as status of 8th nerve and 7th nerve for assessment of possible tumors, Bells Palsy, and other disorders, etc.
Patient Participation – Not necessary usually.
Auditory Brainstem Response (ABR) – Assess electrical signals given off by various inner ear centers, brainstem centers, and brain areas. There are similar tests to this such as “stacked ABR, auditory steady state and others.
Purposes – Assesses hearing loss in patients who cannot respond normally, assesses status of the auditory nervous system for various reasons such as determining disorders such as 8th nerve tumor, auditory neuropathy (when used with oto-acoustic emissions), and auditory processing disorders.
Patient Participation – Not needed except when assessing brain function.
Oto-acoustic emissions (OAE) –Tests hearing (if greater sensorineural loss than 30 dB) by detecting small sounds “emitted” by the healthy ear. A sensitive microphone probe is placed into the ear canal. Sound signals generated from the ear itself are measured, and if present and have normal characteristics, normal hearing is established (“normal” in this case means no worse than 30 dB SN loss).
Purposes – A good test for those who cannot respond to sound with a hand wave, etc. (babies, handicapped patients, etc.). OAE tests the cochlea’s outer hair cell “motility” (ability to move). Another purpose of the test is locate more precisely where the problem is. The test does not assess the hearing nerve (VIII nerve), just the cochlea, therefore, when used in combination with ABR, determination can be made as to the location of the loss. For example, in “auditory neuropathy”, a problem of the VIII nerve or higher, ABR would be abnormal, but OAE would be normal.
Patient Participation –patient does not need to participate, but must be very still and not making noises
(as babies often do).