Hearing tests are used to determine the type and severity of the hearing loss. Several measurements are made during this test for each the right and left ear.
The first test is called air-conduction audiometry. Headphones are used to find the lowest volume that you can hear sound. This represents the normal way sound enters the ear.
The second type of hearing test is called bone conduction audiometry. For this test, a probe is placed behind your ear on the mastoid bone. Vibrations from the probe get transmitted directly to the cochlea, bypassing the ear canal, eardrum, and ossicles. The lowest level of sound you can detect is recorded. This gives us a measurement of how well the actual hearing nerves are working.
If there difference between the air-conduction and the bone conduction tests, it is called a conductive hearing loss. Reasons for a conductive loss include wax in the ear, fluid in the ear, a hole in the ear drum or middle ear bones that are not working normally. Such causes are often treatable.
If there is no difference between the two types of hearing tests, the hearing loss is considered a nerve, or sensory, type of hearing loss. This is a common type of hearing loss that occurs with age or can be noise-related. In some rare instances, this type of hearing loss may recovered if it was sudden in onset.
Another test preformed will determine how well your ear can understand speech. Some people can understand everything if the volume is loud enough. Other people cannot understand a word no matter how loud the volume is. This test is important because hearing aids are only useful if you can still understand spoken words.
The final part of the test checks the pressures in the middle ear. It can be used to document a hole in the ear drum, fluid in the ear, or an ear with pressure problems – essentially one which cannot pop.
These are the most common types of hearing tests. There are others that can be done to give more detailed information. Comparing the results of all the types of hearing tests allows the doctor to accurately determine the cause of the hearing loss.