The Microtone difference will be evident within the first few minutes of your visit when you are promptly greeted by one of our doctors who will walk you in to your appointment. The exam begins with a simple conversation where audiologist asks you questions about your hearing and medical history. The audiologist will then perform a visual inspection of your ears using a light, called an otoscope or video otoscope. This inspection is important to determine if there is anything in the ear canal that may be problematic or could possibly affect the test results such as impacted ear wax.
From there a series of tests will be conducted:
- Pure-Tone Air Conduction Testing: The goal of this test is to determine the faintest tones a person can hear at selected pitches/frequencies, from low to high pitches. Using headphones, or insert ear phones, tones are presented at different frequencies/pitches until the patient can just barely hear them. This test sends the tones through the ear canal, eardrum and middle-ear, cochlea (inner ear) and up the auditory nerve to the brain. It allows the audiologist to know the precise level at which the patient can detect sound through the entire speech frequency range.
- Pure-Tone Bone Conduction Testing: Bone conduction testing is usually performed by having the patient wear a special headset that touches the skull behind the ears. Electric signals are sent that are turned into mechanical vibrations on the skull. Just like the air conduction test, you will “hear” tones being played in each ear and will respond when and if you hear each sound at each frequency. This test bypasses the outer and middle-ear in order to directly test the hearing sensitivity of the cochlea (inner ear). In comparing the bone conduction test to an air conduction test, your audiologist will be able to detect if the problem is primarily with your inner ear (cochlea) or with your outer or middle ear.
- Speech Testing: Speech testing includes 1) Speech reception threshold (SRT) – This test records the faintest speech that can be heard. SRT helps to confirm the pure-tone test results 2) Word recognition score (WRS) – WRS measures the patient’s ability to correctly repeat back words at a comfortable loudness level 3) Speech-in-noise test (QUICK-SIN) –This test measures the ability to hear in a noisy environment. Understanding speech with background noise is a common complaint of people with hearing loss, and this information is helpful in the process of hearing aid fitting.
- Tests of the Middle Ear (Ear Drum and Bones of the middle ear): This includes a series of tests to help determine how the middle-ear is functioning. 1) Tympanometry – Tympanometry pushes air pressure into the ear canal, making the eardrum move back and forth. This test assists in the detection of fluid in the middle ear, perforation (hole) in the eardrum, wax blocking the ear canal, etc. 2) Acoustic reflex measures – A tiny muscle in the middle-ear contracts when a loud sound occurs. The loudness level at which the acoustic reflex occurs—or the absence of the acoustic reflex—gives information to the clinician about the possible location of the hearing problem.
- Otoacoustic Emissions (OAEs): This extremely sensitive objective testing helps detect the function of the outer hair cells in the inner ear. Emission is a soft sound which is generated within the inner ear. People with normal hearing produce emissions. Those with hearing loss greater than 25-30 decibels most often do not produce these emissions.
Hearing Evaluations for Children
For kids, we use many of the same tests outlined above. However, with young child we often use a more play-like activity to indicate response, techniques include:
- Visual reinforcement audiometry (VRA) – This method is performed on children between 6 months – 2 years of age. The child is prompted to look toward a sound source. When the child gives a correct response, the child is “rewarded” through a visual reinforcement on the video screen.
- Conditioned play audiometry (CPA) – This technique is commonly used with children ages 2–5. The child is prompted to perform an activity each time a sound is heard. The activity may involve feeding an animal with pretend treats, placing pegs in a hole, or putting a ring on a cone.