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• What are hearing tests?
• What are the types of hearing tests?
• Who performs hearing tests?
• Testing procedures:
• How frequently should I or my child have hearing tests?
• How can I prevent hearing loss?

Hearing Test

Hearing tests evaluate your hearing ability. They can be screening or diagnostic tests for hearing loss. These tests are painless and require no special preparation.

What are hearing tests?

Hearing tests can assess whether you have hearing loss and determine the extent of the loss. A popular method is audiometry, which uses an audiogram to display the results. These tests are painless and require no special preparation, except for tests in some young children who may require sedation administered under the supervision of a doctor.

Doctors conduct hearing tests to either screen or diagnose hearing loss. If you fail the initial test, further evaluation by an audiologist is necessary to determine the type and severity of the hearing loss.

What are the types of hearing tests?

1. Pure-tone testing determines the lowest sound volume you can hear at each frequency. This type of hearing test involves two sound conduction modes -- air conduction, transmitted via earphones, and bone conduction, by which sound is transmitted through bones using a bone vibrator or bone conductor.
2. Speech Testing involves listening to and repeating specific words to assess how loud the speech needs to be for you to hear and discern speech discrimination.
3. Tests of the Middle Ear measure the movement of the eardrum and middle ear structures in response to air pressure and loud sounds to identify issues such as a perforated eardrum, the presence of fluid, pus, or infection in the middle ear, dysfunction of the Eustachian tube, earwax blockage, or narrowing of the ear canal, etc.
4. Auditory Brainstem Response (ABR) evaluates the neural pathways between the cochlea of the inner ear and the brain stem. It is applicable for testing hearing in children, individuals who cannot complete pure-tone tests, and those with injuries affecting their hearing or patients whose doctor suspects an abnormality of the auditory nerve or acoustic neuroma.
5. Otoacoustic Emissions Test (OAE) assesses inner ear function and is for newborn hearing screening tests. It can estimate hearing levels and monitor hearing loss secondary to ototoxic drugs.

Who performs hearing tests?

Doctors can provide a basic hearing test, but audiologists typically administer more comprehensive tests.

What are the procedures for each hearing test?

1. Pure-tone testing is the most common method

1. Air Conduction Testing
   • You will put on earbuds and sit in a sound-proof room.
   • An audiologist uses an audiometer to emit sound signals at various frequencies and loudnesses.
   • When you hear a sound, you must press a button, raise your hand, or say "Yes."
   • The audiologist will record your responses on an audiogram.
2. Bone Conduction Testing
   1. The audiologist will place a device behind your ear or on your forehead.
   2. This device sends sound vibrations that cause the skull to resonate gently, transmitting the vibrations directly to the inner ear, bypassing the outer and middle ear.
   3. The audiologist will record your responses on an audiogram.

2. Speech Testing

• Your audiologist may conduct a speech with a pure-tone test to evaluate your ability to hear and repeat words.
• You will wear headphones or earbuds; the audiologist will utter two-syllable words at varying loudnesses. You will repeat the words after the audiologist.
• The audiologist will record the softest two-syllable words you correctly repeat.
• The audiologist will speak at a comfortable decibel and ask the individual to repeat a series of one-syllable words, recording the percentage of words repeated after correctly (0-100%).

3. Tests of Middle Ear

The eardrum, a membrane between the outer and middle ear, vibrates when sound waves from the ear canal reach it. It then transmits the vibrations to the middle and inner ear, transforming them into nerve signals that travel to the brain, perceiving them as sound. This examination tests the responsiveness of the eardrum to air pressure and loud sounds.

1. Tympanometry is a test that assesses the excursion of the eardrum. It also helps determine if the Eustachian tube is functioning well.
2. Acoustic Reflex Measure evaluates the reflexive response of the middle ear muscles to loud sounds at various frequencies (500-4000 Hz).
3. Static Acoustic measures assess the air volume in the ear canal to check for blockages, eardrum perforations, or obstructions in tympanostomy tubes inserted by a doctor.

Testing procedures:

• • The audiologist will place a rubber-tipped earbud into your ear canal.
  • You will feel a slight air pressure in the ear and hear intermittent sounds. You must remain still, refrain from speaking or swallowing, and breathe normally during the test.
  • The device will exert air pressure and varying tones into the ear, producing a tympanogram. This graph displays the eardrum excursions, along with numerical values and tables depicting the function of the middle ear.

4. Auditory Brainstem Response (ABR)

The ABR test checks the connections or pathways between your inner ear and the brain. It does not require you to respond to sounds.

• The audiologist will insert spongy, foam-like earbuds in both ear canals.
• The audiologist places electrodes on your forehead and behind the ears or earlobes to record brainwave activity in response to specific sounds played through the earbuds.
• The computer displays your brainwave activity, and the audiologist reviews the printouts to interpret the test results.

5. Otoacoustic emissions test (OAE)

This test evaluates the function of the inner ear by measuring the minute echo produced by the hair cells of the inner ear. These hair cells vibrate when sound waves hit them. In individuals with inner ear hearing loss, the hair cells in the cochlear do not function properly.

• A small soft-tipped probe will be placed and transmit sounds into your ear and measure the sounds that echo back.
• You should remain still for a moment. The screen will display the results.

When will I receive my hearing test results?

Typically, the results are available right after the tests. Your doctor will go over the results with you.

What happens next?

If a test reveals ear canal blockage by earwax or fluids obstructing your middle ear, you may be referred to an ENT doctor for their removal before the hearing test.

If the pure-tone testing indicates hearing loss, the doctor will explain the results and proceed with the following steps:

1. Inform you about the degree of hearing loss, whether mild, moderate, or severe, and the type and cause of your hearing loss.
2. Discuss treatment options, including medication, ear drops, earwax removal, surgery, hearing aids, or cochlear implants.
3. If necessary, refer you to an audiologist to discuss hearing aids, try out different devices, and assist in selecting the most suitable hearing aid to ensure maximum benefit and lifestyle compatibility.
4. Schedule follow-up appointments or refer the patient for cochlear implants or auditory and speech therapy.

How frequently should I or my child have hearing tests?

• In Children: Newborns will undergo a hearing test 24 hours after birth or before they go home. For infants not born in a hospital, it is advisable to have a hearing test as soon as possible. Every child should complete a hearing screening by the age of one month.

Hearing impairment can significantly impact child development, including language and speech development, unclear speech or speech disorders, poor academic performance, inappropriate personal and social adaptation, and emotional and psychological disturbances.

When your child starts school, the school may conduct hearing screenings using Pure-tone testing, which can indicate whether the child passes or fails. If failing the test, you should bring your child in for further evaluation.

• In Adults: Adults aged 18 and above without evident hearing issues and not deemed at risk should undergo hearing screenings at least once every decade. Upon reaching age 50, this frequency should escalate to every three years. People exposed to workplace or environmental noise levels exceeding 85 dBA should have a hearing test annually. Those exposed to noise levels above 100 dBA should have hearing tests every six months.

Regarding treatments for hearing loss, options vary depending on its underlying cause. Though a full recovery may not always be possible, we can deal with most hearing loss. Common treatment modalities include hearing aids, auditory osseointegrated implants, bone-anchored hearing implants, cochlear implants, tympanostomy tubes, endoscopic ear surgery, and aural rehabilitation.

How can I prevent hearing loss?

1. As you age, hearing loss develops gradually due to natural deterioration. Nevertheless, you can mitigate this progression by:
2. Avoid and limit the time spent on activities with loud noises
3. If you must be in a noisy environment, wear protective devices such as earplugs or noise-canceling earmuffs. Monitor safe listening levels, such as setting the volume on audio devices to no more than 60% of the maximum volume and limiting your exposure to loud noise to less than one hour per day. Use applications that monitor and alert you when you exceed safe listening limits (e.g., 80 dBA for 40 hours per week).
4. Observe warning signs of hearing loss, such as decreased hearing ability, difficulty understanding speech, especially on the phone or television, needing to increase the volume, trouble following conversations in noisy environments, tinnitus (ringing in the ears), ear pain, discharge of blood or pus from the ear, ear fullness, and dizziness. If any of these symptoms occur, see a doctor promptly.
5. Have a hearing screening test as part of your annual health checkup to detect early signs of hearing loss and address them promptly.

If you suspect or develop hearing problems, consult a doctor for the proper diagnosis to pinpoint the underlying cause.

A note from MedPark Hospital doctors

Hearing assessments are valuable in evaluating age-related hearing loss. If you suspect hearing problems, it is advisable to consult with a doctor and a skilled audiologist.