Audiologic Testing for Hearing Loss

When assessing an individual with possible hearing loss, specialized tests are performed to better determine the exact type of hearing loss and possible causes. When patients come to the Center for Otosclerosis, three highly sophisticated tests are done to fully evaluate the ear. These tests are administered by highly trained Doctors of Audiology to ensure that the results are accurate and precise. These tests are critical when discussing treatment options with the Center for Otosclerosis Medical Physicians.

Audiometry (Hearing Test)

The main purpose of a hearing test is to determine the degree, configuration and type of hearing
loss. The results of the test are recorded on an audiogram, a graphic chart of hearing results. 
Results from your audiometric evaluation will help determine the nature of hearing loss
(conductive vs. mixed) and if one or both ears are affected. Testing is completed pre-operatively
as well as post-operatively. Otosclerosis typically causes one of the following:

  • Conductive hearing loss is caused due to lack of sound transmission through the middle ear and hearing bones. Otosclerosis causes poor movement, or fixation, in the 3rd hearing bone, the stapes bone. The immobility of the stapes bone causes the conductive hearing loss.
  • Mixed hearing loss is a combination of conductive hearing loss and sensorineural hearing loss (damaged inner ear and/or auditory nerve function). Otosclerosis can affect the inner ear as well and this process can cause sensorineural hearing loss in addition to the conductive hearing loss, thus causing a mixed hearing loss.

The specific type of hearing loss will dictate management options and can be determined by
detailed hearing tests.

Audiologist hearing test image
Audiologist hearing test instruments

Tympanometry (Acoustic Immittance testing)

Middle ear function can be assessed through tympanometry, which will help determine the mobility of the eardrum and help diagnose middle ear problems. A gentle puff of air is sent into the ear canal and the amount the eardrum moves in response to change in air pressure is recorded. The test is quick and painless. This test can help differentiate the various potential causes of conductive or mixed hearing loss by assessing how well the eardrum moves and whether there is a perforation in the eardrum or fluid in the middle ear cavity.

Acoustic Reflex Thresholds (ARTs)

Acoustic Reflex Thresholds assessment takes a deeper look at middle ear function, specifically involving the contraction of the stapedius muscle. The stapedius muscle is the smallest muscle in your body that connects to the stapes bone. This muscle contracts and stiffens the stapes bone and the eardrum in response to louder sounds, thus serving to protect our inner ear when we are exposed to loud sudden sounds. The acoustic reflex pathway involves both the sensory and motor pathways of the 7th and 8th cranial nerves. At the Center for Otosclerosis, we check ART to assess the reflex pathway. In otosclerosis, the reflex pathway is not active because the stapes bone is already immobile, thus not allowing the stapedius muscle to contract and limit the motion of the stapes bone as it should in normal ears. Performing this test allows us to further confirm the diagnosis of otosclerosis.

older man taking a audiologist hearing test