Audiology Tests and Procedures
Overview
Audiology tests and procedures check how well a person can hear and how well their ears are working. These tests help detect hearing problems early, so people can get the treatment they need to improve their hearing and quality of life. Most hearing tests are simple and painless, making them safe for people of all ages.
During an audiology test, a person usually wears headphones or earpieces while listening for different sounds, tones, or words. The results show how well someone can hear at different pitches and volumes. This helps audiology experts find the best solution for each person’s hearing needs.
Understanding Audiology and Hearing Loss
Hearing depends on a series of steps inside the ear and brain. Audiology is the branch of healthcare focused on hearing health, while hearing loss can develop for many reasons and affects how well people communicate.
How Hearing Works
The ear has three main parts: outer ear, middle ear, and inner ear. The outer ear collects sound waves and sends them down the ear canal to the eardrum. The eardrum vibrates, moving tiny bones in the middle ear. These bones pass the vibrations to the inner ear, which has the cochlea.
In the cochlea, tiny hair cells turn the vibrations into signals for the brain. The brain interprets these signals as sound. Damage or blockages in any part of this pathway can change how well someone hears.
What Is Audiology?
Audiology encompasses the study of hearing, balance, and associated issues. Audiologists, as medical professionals, test, diagnose, and manage hearing loss and balance disorders. Some key responsibilities of audiologists include:
- Performing hearing tests, such as audiograms and pure-tone tests.
- Identifying types and causes of hearing loss.
- Fitting and adjusting hearing aids and other devices.
- Helping with balance issues related to the ear.
Causes and Types of Hearing Loss
Many different factors can cause hearing loss. Some common causes are aging, loud noise exposure, ear infections, genetics, and injury. Sometimes, a buildup of earwax or fluid in the ear can also reduce hearing. There are three main types of hearing loss:
| Type | Where It Happens | Example Causes |
|---|---|---|
| Conductive | Outer/Middle Ear | Fluid, infection, wax |
| Sensorineural | Inner Ear/Nerve | Aging, noise, genetics |
| Mixed | Both areas | Combination of factors |
Role of the Audiologist
An audiologist plays a key role in hearing health. They begin with exams like otoscopy, which involves looking inside the ear with a lighted tool, and they conduct several hearing tests, including the pure-tone hearing test. After diagnosing the type and level of hearing loss, audiologists explain the results and make treatment plans.
This might include recommending hearing aids, cochlear implants, or therapy for communication. Audiologists help track changes in hearing, fit devices properly, and support patients in adjusting to hearing loss. They are important members of the healthcare team for both children and adults.
Common Signs of Hearing Loss
Hearing loss often happens slowly, so people may not notice it right away. They may start to ask others to repeat themselves more often than before. Some people find it hard to hear conversations, especially in noisy places like restaurants or group gatherings. Voices might sound muffled, or soft sounds may become harder to notice. Common signs of hearing loss include:
- Trouble understanding words, especially with background noise.
- Needing to turn up the volume on the TV or radio.
- Often asking others to speak more clearly or loudly.
- Withdrawing from conversations.
- Missing doorbells, alarms, or phone rings.
People may also feel tired after trying to listen for a long time. Straining to hear can take extra effort and lead to frustration. Children with hearing loss might seem inattentive or have trouble following directions. They could start speaking later than usual or may not react to soft sounds. A person who notices these signs should consider a hearing test.
Preparing for an Audiology Appointment
Getting ready for an audiology appointment helps things go smoothly. Patients should bring a list of current medications and note any hearing problems. Write down questions or concerns to discuss with the audiologist.
Doctors may ask about medical history and any previous ear problems, so be honest about symptoms such as hearing loss, ringing in the ears, dizziness, or ear pain. It is helpful to check with your insurance beforehand. Some plans need a referral from a primary doctor before seeing an audiologist.
Knowing what your insurance covers can prevent unexpected costs. Bringing a friend or family member can make the experience less overwhelming. They can help remember important information and offer support during the visit. Use the checklist below to prepare:
| Task | Done (✔/✗) |
|---|---|
| List medicines and supplements | |
| Note hearing issues or questions | |
| Check insurance and referrals | |
| Bring ID and insurance card | |
| Ask a friend to join if possible | |
| Gather records from past visits |
Pure Tone Audiometry
Pure tone audiometry is a common method used to check for hearing loss. It measures how well a person hears sounds at different frequencies and volumes using specialized equipment called an audiometer.
During the test, the person wears headphones and listens for beeps or tones that vary in pitch and loudness. Each time a sound is heard, the person signals to the examiner by pressing a button or raising a hand. The examiner records the quietest sounds the person can hear at each pitch—these are called hearing thresholds.
The results appear on a chart called an audiogram, which shows the softest sounds a person can hear at different frequencies, measured in decibels (dB). Audiologists use this information to determine the type and degree of hearing loss.
Air Conduction Testing
Air conduction testing forms the main part of pure tone audiometry. It checks how sound passes through the ear canal, eardrum, and middle ear to the inner ear. Headphones or ear inserts deliver tones directly into each ear.
The audiometer provides various tones at different loudness levels and frequencies. The lowest level at which a person detects the sound at each frequency becomes their air conduction threshold. These thresholds are plotted on the audiogram.
This test can reveal if hearing loss is present but does not show if the source is in the outer, middle, or inner ear. Audiologists often use it together with bone conduction testing for a complete picture.
Bone Conduction Testing
Bone conduction testing checks how well the inner ear works by sending sound directly to it. The audiologist places a small device, called a bone oscillator, behind the ear on the mastoid bone during the test. The bone oscillator sends vibrations through the skull, bypassing the outer and middle ear.
Audiologists compare these results to those from air conduction testing. If someone hears better through bone conduction than air conduction, it suggests an issue with the outer or middle ear. If both results are about the same, the issue is likely in the inner ear itself. This helps distinguish between conductive hearing loss and sensorineural hearing loss.
Tympanometry and Middle Ear Evaluation
Tympanometry and related tests play an important role in checking the health and function of the middle ear. These tests help audiologists find ear problems that may cause hearing loss or discomfort.
Understanding Tympanometry
Tympanometry is a simple and quick test. It checks how well the eardrum moves when air pressure in the ear canal changes. A small device is placed in the ear, sending a soft tone and a gentle puff of air. This test does not measure hearing directly.
Instead, it helps identify issues like fluid in the middle ear, eardrum perforations, and problems with the Eustachian tube. Health professionals often use tympanometry with other hearing tests for a complete evaluation. Tympanometry is helpful for people of all ages, especially children who get ear infections often.
Tympanogram Interpretation
The results of tympanometry are shown on a graph called a tympanogram. This graph shows how well the eardrum moves. Different shapes on the tympanogram can mean different middle ear issues.
- Type A: Normal eardrum movement (middle ear works well).
- Type B: Flat line (may show middle ear fluid or a hole in the eardrum).
- Type C: Shifted curve (suggests Eustachian tube problems or negative pressure).
Clinicians read these results to find out if the middle ear has fluid, is working normally, or is not moving as it should. Quick and correct interpretation helps decide what steps to take next.
Acoustic Reflex Testing
Acoustic reflex testing works with tympanometry to check how the middle ear responds to loud sounds. In this test, the examiner plays a loud tone and measures how middle ear muscles contract to protect the inner ear.
If the muscles react as expected, the middle ear pathway is likely working. If no reflex appears, this may indicate a problem in the middle ear, the nerve pathways, or in the brainstem. A lack of reflex can point to nerve damage or fluid in the ear.
This extra test gives more detail and can help diagnose certain nerve-related hearing problems. It also helps confirm the findings from tympanometry and gives a clearer picture of total ear health.
Speech Audiometry
Speech audiometry includes hearing tests that help audiologists measure how a person hears and understands speech. These tests matter because hearing speech is different from hearing simple tones. Speech testing provides a closer look at how well a person’s ears and brain process spoken words.
There are two main tests: speech reception threshold (SRT) and word recognition. The SRT finds the quietest level at which a person can repeat back at least half of the words spoken to them. Audiologists often use “spondaic” words, which are two-syllable words with equal stress, for the SRT. Word recognition tests check how clearly someone can hear and repeat words at a comfortable loudness level.
| Test Name | What It Measures |
|---|---|
| Speech Reception Threshold (SRT) | Softest level for repeating words |
| Word Recognition | Ability to identify spoken words correctly |
Audiologists use different equipment, such as headphones or speakers, to present the words. They may conduct speech tests in quiet or with background noise, depending on what they want to find out.
Auditory Brainstem Response (ABR) and Otoacoustic Emissions Tests
ABR evaluates the responses of the auditory nerve and the brain to sound stimuli. The audiologist places small electrodes on the head and sends sounds through earphones. The test measures the electrical activity in the brain when the ear hears a sound. Key features of ABR:
- Uses electrodes placed on the scalp.
- Checks hearing pathway from the inner ear (cochlea) to the brainstem.
- Often used for newborns, infants, or people who can’t respond to normal hearing tests.
OAE tests show how well the inner ear works, especially the outer hair cells in the cochlea. The audiologist places a tiny probe in the ear canal, makes sounds, and listens for echoes produced by the ear itself. Healthy outer hair cells in the cochlea create these emissions. Important points about OAE:
- Quick and painless.
- No need for the patient to respond.
- Can help find hearing loss in babies and young children.
| Test | What It Measures | How It’s Done | Main Use |
|---|---|---|---|
| ABR | Brain response to sound | Electrodes on the head | Auditory nerve, brainstem |
| OAE | Cochlea function | Probe in ear canal | Outer hair cell function |
Both ABR and OAE tests are objective measures. The results do not depend on a person’s actions or responses. This makes them helpful for testing hearing in people who cannot participate in regular hearing tests.
Specialized Hearing Tests and Procedures
Specialized hearing tests help audiologists pinpoint hearing problems that basic tests might miss. Audiologists often use these tests to better understand certain conditions like sensorineural hearing loss or tinnitus.
Weber Hearing Test
The audiologist places a tuning fork on the middle of the forehead and asks patients where they hear the sound: in one ear or both. This quick check helps identify if hearing loss is sensorineural or conductive.
Other Common Specialized Tests
- Tone Decay Test: The audiologist measures how long a person can hear a sound at a set volume to detect possible nerve-related hearing loss.
- Short Increment Sensitivity Index (SISI): The test checks for small changes in loudness to help find where the hearing problem starts in the ear.
- Stenger Test: Audiologists use this when people report hearing loss in only one ear to determine if the reported hearing loss is real or not.
People with tinnitus sometimes undergo extra tests to match the sound and pitch of the ringing they hear. These tests can help guide treatment or management.
| Test Name | Main Purpose |
|---|---|
| Weber Hearing Test | Identifies type of hearing loss |
| Tone Decay | Detects nerve-related hearing loss |
| SISI | Locates area of auditory dysfunction |
| Stenger | Confirms one-sided hearing loss is genuine |
What to Expect After Testing
After completing audiology tests, the audiologist will review the results and explain what they mean. These outcomes may confirm normal hearing or identify the type and severity of hearing loss.
If hearing loss is found, the audiologist will recommend next steps, which may include hearing aids, medical treatment, or further evaluation. The results also help guide decisions about assistive devices, communication strategies, or referrals to other specialists.
