Hearing tests are an essential part of detecting hearing problems in newborns, young children, and adults. To recognize hearing abnormalities, several types of hearing tests are available, but Otoacoustic Emissions (OAE) and Brainstem Evoked Response Audiometry (BERA) are popular among all. Typically, both OAE and BERA tests evaluate hearing, but they differ greatly in approach, measurements, and objectives. OAE tests will usually assess sounds produced by the cochlea, whereas BERA tests will measure electrical responses of the auditory nerve and brainstem. If you want to get a deeper understanding of the difference between OAE and BERA and their roles in hearing assessment and diagnosis, read this blog post. Here, we have presented the distinctions between OAE and BERA tests along with their definitions, procedures, benefits, and limitations.
Understanding OAE Test
The Otoacoustic Emissions (OAE) test is an objective, non-invasive method that measures the sounds produced by the cochlea in response to sound stimulation. It is commonly used for neonatal hearing screening and diagnostic testing in infants and adults. The duration of the OAE test is approximately 1-5 minutes for each ear.
How Does the OAE Test Work?
OAE tests will be performed with an OAE device (otoacoustic emission analyzer), soft-tip earphones or ear cups, and a sensitive microphone (probe). During the test.
- The patient will have to sit comfortably in a quiet room.
- The ear canal will be gently cleaned, and the probe will be inserted.
- Soft sounds (clicks or tones) will be introduced through earphones.
- The microphone will record faint sounds emitted by the cochlea.
- The OAE device will analyze and amplify the recorded emissions.
- The device will detect and display the OAE response.
The OAE test results will be interpreted as follows: the presence of emissions (pass) indicates normal cochlear function, while the absence or reduced emissions (fail) suggests potential hearing loss or cochlear dysfunction.
What Does the OAE Test Measure?
The OAE Test measures the following
- Cochlear Function: The test evaluates the cochlea’s ability to create sound.
- Hearing Threshold: OAE measures hearing sensitivity and identifies potential hearing loss.
Advantages of the OAE Test
- Quick and painless
- Objective results
- Easy to administer
Limitations of the OAE Test
- Neural hearing impairments such as injury to the auditory nerve could go undetected.
- Problems with the middle ear may affect the test accuracy.
- Restricted to evaluating cochlear function rather than whole hearing.
Understanding BERA Test
Brainstem Evoked Response Audiometry (BERA) test is an objective neurophysiological evaluation tool that assesses the electrical responses of the auditory nerve and brainstem to sound stimuli. This test is intended for diagnostic purposes, particularly for suspected neural hearing losses. The approximate time duration to perform the BERA test is 30-60 minutes.
How Does the BERA Test Work?
BERA test will be conducted with equipment such as a BERA device (brainstem evoked response audiometer), Earphones, and Electrodes (on scalp and ears). During the test
- The patient will have to sit comfortably in a quiet room.
- Electrodes will be placed on the scalp and ears and earphones will be positioned.
- Clicks or tones will be introduced through earphones.
- Electrodes will record brainwave responses.
- The BERA device will analyze and average responses.
- The device will generate a waveform displaying a brainstem response.
The key components of the BERA waveform will typically vary between Waves I-V. Overall, the BERA test interpretations will involve analyzing latency, amplitude, and interpeak latency. Upon completion of the BERA test, the results will be presented as normal or abnormal based on waveform and latency expectations.
What Does the BERA Test Measure?
The BERA test measures the following
- Auditory nerve function
- Brainstem function
- Hearing threshold (0-90 dB range)
- Neural conduction velocities
Advantages of the BERA Test
- Accurate assessment of hearing threshold and neural function
- Painless, non-invasive, and objective
- Beneficial for young kids, newborns, and non-cooperative patients
Limitations of the BERA Test
May not identify middle ear problems
- Limited to evaluating brainstem and auditory nerve function
- Interpretation requires knowledge
OAE vs. BERA: Learn the Key Differences
Here, let us look at the crucial difference between OAE and BERA based on different aspects.
Test Methodology
OAE: Measures the sound produced by the cochlea in response to auditory stimulation.
BERA: Measures electrical responses in the brainstem and auditory nerve.
Measurements
OAE: Evaluates the integrity of outer hair cells and cochlea function.
BERA: Assesses brainstem and auditory nerve activity as well as neural conduction velocities.
When to Use Each Test
OAE: For newborn hearing screening, to assess young children suspected of having hearing loss, and to monitor cochlear function.
BERA: To diagnose auditory nerve and brainstem disorders and to estimate hearing thresholds. It is highly recommended in case of suspected neural hearing losses, auditory neuropathy, or brainstem lesions, and for patients with neurological disorders such as multiple sclerosis.
Choosing the Right Hearing Test: OAE vs. BERA
When it comes to selecting the appropriate hearing test between OAE and BERA, certain factors such as age, suspected condition, diagnostic objectives, test complexity, and duration, patient cooperation should be considered. OAE is ideal for newborn hearing screening and cochlear function monitoring. On the other hand, BERA is suitable to evaluate auditory nerve and brain stem function. OAE test is the best for newborns/young children and cochlear function assessment and BERA is right for suspected auditory nerve or brainstem dysfunction, hearing threshold estimation, or limited patient cooperation.
Conclusion
OAE and BERA are the two essential diagnostic instruments for evaluating hearing and auditory function. Knowing the differences between OAE and BERA will be helpful for healthcare providers in selecting suitable hearing tests for their patients. While OAE examines the cochlear function, BERA assesses auditory nerve and brainstem function, providing important information for accurate diagnosis and therapy. If you or a loved one has concerns about hearing loss or auditory impairment, contact our trained audiologists at Asha Speech and Hearing Clinic, New Delhi. Our state-of-the-art facilities offer comprehensive OAE and BERA testing to ensure accurate diagnoses and personalized treatment plans.