Pure tone audiometry is a behavioral test used to determine hearing sensitivity. During testing, you will be seated in a sound-treated room, and will be wearing either foam inserts or headphones. You will be asked to press a button each time you hear a sound. The quietest sounds that you hear, called a threshold, will be graphed on an audiogram. The audiogram displays the results of your hearing test showing the type, degree, and configuration of hearing loss present.
If hearing loss is identified, it is imperative to understand the type of hearing loss present in order to determine if the loss can be surgically or medically treated. Hearing loss is defined as one of three types: conductive, sensorineural, or mixed. A conductive hearing loss involves the outer or middle ear. A sensorineural hearing loss involves the inner ear. A mixed hearing loss is a combination of a conductive hearing loss and sensorineural hearing loss. Conductive and mixed hearing losses may be surgically or medically treatable. Sensorineural hearing loss is most likely permanent.
Determining the type of hearing loss involves use of a bone oscillator, which sends vibrations into the inner ear, bypassing the outer ear and middle ear. Conductive hearing loss is identified when the patient hears better by bone conduction than air conduction. Sensorineural hearing loss is identified when bone conduction thresholds are equal to the air conduction thresholds. A mixed hearing loss occurs when there are both conductive and sensorineural components present.