What To Expect From A Hearing Test
If you or your child has been referred for a diagnostic audiologic evaluation, it could mean that hearing loss is present, or it needs to be ruled out with further testing. The diagnostic audiologic evaluation may be indicated for individuals who did not pass an initial hearing screening.
The complete audiologic evaluation will detail the type and severity of the hearing loss. These results can provide insight in to the cause of the hearing loss in many cases, as well as provide guidance for the audiologist in making appropriate treatment recommendations.
What Tests Will Be Done?
The specific tests done during the comprehensive hearing evaluation will depend on the patient’s age, and cognitive ability. Prior to the hearing testing, the audiologist may perform otoscopy (examining the ear canal) and tympanometry (gentle pressure test of eardrum movement) to determine the health of the ear canal and the middle ear. An OAE (otoacoustic emissions) screening test is routinely done at many offices prior to hearing testing. OAE screeing is a test of the cochlea’s hair cell function inside the inner ear. Hearing testing done inside the sound-isolated booth will include pure tone air and bone conduction testing, as well as speech testing. Most adults and older children are able to complete this full evaluation easily within 20 to 30 minutes.
Pure-tone Air and Bone Conduction Testing
Pure-tone air conduction testing determines the quietest tones that a person can hear at different frequencies, both low and high. Bone conduction testing is similar to pure-tone air conduction testing but instead of headphones delivering the sound, a bone oscillator is placed on the mastoid bone behind the ear to deliver pure tones. The results help the audiologist determine what type of hearing loss is present – conductive, sensorineural, or mixed.
Speech Recognition Testing
A speech recognition threshold (SRT) test consists of two-syllable words that are repeated at the softest level. The value obtained confirms the validity of the pure tone air test results and is a reflection of the lowest level at which the patient can recognize words or speech stimuli.
Word Discrimination Testing
A “discrim” test is done usually at a comfortable listening level and the patient is asked to repeat a list of 25 to 50 words. A carrier phrase is said prior to each word to make a complete sentence. Each test word missed has a value of -4 or -2 points that is then subtracted from 100. The score obtained for each ear is usually a good indicator of someone’s ability to process speech in a quiet environment.
Along with the evaluation, you should generally expect to have time to review the results with the audiologist. He or she can interpret the tests for you, answer your questions, provide you with information and referrals as needed, as well as begin planning for treatment, if indicated. Audiologists are specialists in hearing and hearing rehabilitation. Never hesitate to ask your audiologist for clarification or further information on anything you do not understand.