Hearing Tests for Adults
There are a number of different ways to test adult's hearing loss. Some of these are briefly described below.
In otoscopy, doctor examines a patient's ear by looking through an instrument know as Otoscope as described in the picture on the page. Otoscope is nothing complicated but a magnifying lens with a built in torch in it.
Pure Tone Audiometry (PTA):
PTA tests the combined hearing of both ears. During the PTA test, audiometer (a medical equipment to generate sounds) generates sounds at different volumes and frequencies. During the test, a person listen to the sounds using headphones and press a button when he/she hears the sound.
Fig 2: AOAE Test Procedure
Automated Otoacoustic Emissions Testing (AOAEs):
During AOAE test a small foam tip is inserted into the patient's ear. Then clicking sound is played into patient's ear and he/she needs to be still and quiet. Patient doesnt need to provide any response and its fully automated. AOAE takes anywhere between 30 seconds to one minute and give an indication of person's hearing level.
Auditory Brainstem Response (ABR):
Also known as brainstem evoked response (BSER) testing, it is a screening test to detect the hearing loss in the patient. In ABR test hearing related electrical activities in the brain are recorded by placing electrodes on the scalp. ABR test shows the degree of the hearing loss if present in the patient. This test is also used to test the functioning of ear, cranial nerve and some brain functions related to hearing system. ABR is a a safe and painless test.
The speech perception test (which is also know as as a speech audiometry or speech discrimination test), involves testing the abilities of patient to hear words without using any visual cue (like lip reading or body language). During this tests words are played through instruments (head phone, recorder etc.) or spoken by a non visible tester, and the patient is asked to repeat the words. During the test, usually there is presence of some background noise.
Fig 3: "Tympanometry Test
Tympanometry is used to test the presence of any fluid in behind the eardrum and can also tell if the Eustachian tube is working properly. For a person with normal hearing most of the sound should pass through eardrum to inner ear without reflecting any through the eardrum. If any sound is reflected back from the eardrum, then person's hearing is affected. this test is performed by sealing the patient's ear using a small plastic stopper (bung) and then changing the pressure in ear via the machine. During this test, it measures the pressure behind the ear drum and any its movement.
Whispered voice test:
The whispered voice test is the simplest hearing test and is performed without any equipments. This test can be performed anywhere. during the test, one of the ear of the patient is blocked and the tester speaks/whisper words at different level of loudness and the patient is asked to repeat the words.
Tuning fork (Webber's and Rinne's) test:
Fig 3: "Tuning Fork (Webber's and Rinne's) Test
A tuning fork is a simple instrument which generate sound waves (vibrations) at a fixed pitch. The sound waves are produced by gently tapping the tuning fork. Tuning fork is used for testing different aspects of patient's hearing. During the test, the tester generate sound waves by tapping the tuning fork (on their elbow or knee to make). Just after tapping the tuning fork, the tester place is on the patient's head (at different places) to determine if the hearing loss is conductive (related to outer or middle ear) in nature or it is sensorineural (related to inner ear. More about different kind of hearing loss can be found at the Types of Hearing Loss page.
Bone conduction test:
A bone conduction test is performed to check how well your inner hear/hearing nerves are performing. Bone conduction bypasses outer and middle ear by sending the sounds directly to inner ear through the vibration in bones (rather than through eardrum). Bone conduction test can be performed using a tuning fork, and when used in conjunction with Pure Tone Audiometry (PTA) test, it can pin point which part of the ear is causing the hearing loss.