Diagnostics
Hearing Test
What is a hearing test?
Hearing tests check how well the individual can hear. When sound enters the ear, it makes the eardrum vibrate. These vibrations move deeper into the ear and stimulate nerve cells. These cells send signals to the brain, which helps understand and recognize different sounds.
This test is called audiometry, audiography, audiogram, or sound test.
Who performs hearing test?
When does hearing loss occur, and what are the types?
Hearing loss can occur when there are issues with the ear’s structure, the nerves inside the ear, or the part of the brain responsible for hearing. There are three main types of hearing loss:
- Sensorineural (nerve deafness): This type of hearing loss is caused by problems with the ear’s structure or the nerves involved in hearing. It can be present from birth or develop later in life. Sensorineural hearing loss is typically permanent and can range from mild (difficulty hearing certain sounds) to profound (inability to listen to any sounds).
- Conductive: This type of hearing loss happens when a blockage prevents sound from reaching the inner ear. It can occur at any age but is most common in infants and young children. Common causes include ear infections or fluid buildup in the ears. Conductive hearing loss is usually mild, temporary, and treatable.
- Mixed: Mixed hearing loss is a combination of sensorineural and conductive hearing loss.
Hearing loss is common among older adults, with around one-third of adults over 65 experiencing some form of hearing loss, often of the sensorineural type.
What is the reason for undergoing a hearing test?
The hearing test is needed if the patient experiences any of the following signs of hearing loss:
- Difficulty understanding people, especially in noisy places.
- Frequently asking others to repeat themselves.
- Struggling to hear high-pitched sounds.
- Needing to increase the volume on TV or music player.
- Hearing a ringing sound in ears.
What are the different types of hearing tests?
Different types of hearing tests are available to assess hearing abilities. These tests typically involve checking the response to various tones, words, and noise environments. Here are some common sound tests:
- Pure-tone Test (Audiometry): This is the most common hearing test where the patient sits in a quiet room designed to minimize background noise. The patient is asked to wear headphones or insert earphones. An audiologist uses a machine called an audiometer to deliver sounds at various frequencies and volumes. The patient communicates their perception of these sounds by raising their hand, pressing a button, or affirmatively responding with “yes.” The audiologist documents these responses on an audiogram, which shows the pattern and degree of hearing loss if present.
- Tuning Fork Tests: A tuning fork, which produces a tone when it vibrates, is used to assess hearing. The tuning fork is placed behind the ear or on top of the head. Patients are then prompted to signal the detection of the sound and indicate the ear in which it is heard. This test helps identify hearing loss and the type of hearing loss (conductive or sensorineural).
- Speech and Word Recognition Tests: The patient is asked to wear headphones or insert earphones like the pure-tone test. The patient listens to simple words spoken at different volumes and repeats them. The softest speech the patient can hear is recorded; some testing may occur in noisy environments.
- Tympanometry: This test assesses how well the patient’s eardrum moves. A small device is placed in the ear canal, and the air is gently pushed into the ear, causing the eardrum to vibrate. The movement is recorded on graphs to detect issues like infections, fluid or wax buildup, or damage to the eardrum.
- Otoacoustic Emissions (OAE) Test: This test measures sounds produced by the inner ear in response to a stimulus. It helps evaluate the functioning of the cochlea, the sensory organ responsible for hearing. OAE testing involves inserting a small probe into the ear canal and measuring the emitted sounds.
- Auditory Brainstem Response (ABR) Test: This test assesses the electrical activity of the auditory nerve and brainstem in response to sound. It can help diagnose hearing loss in infants, young children, or individuals who cannot provide reliable behavioral responses. ABR testing involves placing electrodes on the scalp and measuring the brain’s responses to sounds.
What do the results mean?
The hearing test results can provide information about hearing abilities and the type of hearing loss the patient may have.
If the patient has sensorineural hearing loss, the results may indicate the following levels of severity:
- Mild: Difficulty hearing certain sounds, such as high or low tones.
- Moderate: Difficulty hearing many sounds, especially speech in noisy environments.
- Severe: Difficulty hearing most sounds.
- Profound: Inability to hear any sounds.
The treatment and management options for sensorineural hearing loss will depend on the severity of the condition.
If the patient has conductive hearing loss, the doctor may suggest medications or surgery based on the underlying cause of the hearing loss.
What are treatment options for hearing loss?
Even mild hearing loss can significantly impact understanding normal speech, leading many older adults to avoid social situations, which can result in feelings of isolation and depression. However, there are ways to manage hearing loss and prevent these problems. Treatment options include:
- Hearing aids: These devices, worn either behind or inside the ear, amplify sounds to make them louder. Some hearing aids offer advanced features. An audiologist can help determine the best hearing aid as per the patient’s need.
- Cochlear implants: This surgically implanted device is typically used for individuals with more severe hearing loss who do not benefit significantly from hearing aids. Cochlear implants directly stimulate the hearing nerve, enabling sound perception.
- Surgery: Certain types of hearing loss, such as issues with the eardrum or tiny bones in the ear, can be treated surgically.
It is important to consult an audiologist to determine the most suitable treatment option based on hearing needs.
References
- Cleveland Clinic. Hearing test. Available from: https://my.clevelandclinic.org/health/diagnostics/24104-hearing-test
- Hearing tests for adults. Available from: https://medlineplus.gov/lab-tests/hearing-tests-for-adults/
