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Physician Services
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HearBright, an Audiology Corporation, offers the services below:
In addition the following products are offered:
The test results assist the physician to diagnose and treat medical conditions of the ear. The results are also used to determine the next step for vestibular conditions. Following treatment or resolution, the test results are also used for adjustment of your hearing aids.
Pure-tone Audiometry
Pure-tone audiometry is completed in a soundproof booth- a room with special treatment to the walls, ceiling, and floor to ensure that background noise does not affect test results. Only those sounds that the audiologist introduces into the room, either through earphones or through speakers located in the room, will be heard. Sounds may also be sent through a special headset "vibrator" that has been placed just behind the ear or on the forehead.
In testing hearing for tones, a pure tone air conduction hearing test is given to find out the faintest tones a person can hear at selected pitches (frequencies) from low to high. During this test, earphones are worn and the sound travels through the air in the ear canal to stimulate the eardrum and then the auditory nerve. The person taking the test is instructed to give some type of response such as raising a finger or hand, pressing a button, pointing to the ear where the sound was received, or saying "yes" to indicate that the sound was heard.
Sometimes children are given a more play-like activity (conditioned play audiometry) to indicate response. They may be instructed to string a peg, drop a block in a bucket, or place a ring on a stick in response to hearing the sound. Infants and toddlers are observed for changes in their behavior such as sucking a pacifier, quieting, or searching for the sound and are rewarded for the correct response by getting to watch an animated toy (visual reinforcement audiometry).
The audiologist uses a calibrated machine called an audiometer to present tones at different frequencies (pitches) and at different intensity (loudness) levels. A signal of a particular frequency (something like a piano note) is presented to one ear, and its intensity is raised and lowered until the person no longer responds consistently. Then another signal of a different frequency is presented to the same ear, and its intensity is varied until there is no consistent response. This procedure is done for at least six frequencies. Then the other ear is tested in the same way.
The frequency or pitch of the sound is referred to in Hertz (Hz). The intensity or loudness of the sound is measured in decibels (dB). The responses are recorded on a chart called an audiogram that provides a graph of intensity levels for each frequency tested.
In some cases, it is necessary to give a pure tone bone conduction hearing test . In this test, the tone is introduced through a small vibrator placed on the temporal bone behind the ear (or on the forehead). This method "by-passes" blockage, such as wax or fluid, in the outer or middle ears and reaches the auditory nerve through vibration of skull bones. This testing can measure functionality of the inner ear independent of the functionality of the outer and middle ears.
Air conduction test results indicate hearing losses that are either conductive or sensorineural. Bone conduction test results reflect only the sensorineural component. By comparing air conduction and bone conduction test results, the audiologist can determine whether there is a hearing loss due to a problem in the outer or middle ear. If air and bone conduction thresholds are the same, the loss is sensorineural. If there is a difference between air and bone thresholds (an air-bone gap), the loss is conductive or mixed.
Speech Audiometry
Speech audiometry includes determining speech reception threshold (SRT) and testing of word recognition . Speech reception threshold testing determines the faintest level at which a person can hear and correctly repeat easy-to-distinguish two-syllable (spondaic) words. Examples of spondaic words are "baseball", "ice cream", "hot dog", "outside", and "airplane.". Spondaic words have equal stress on each syllable. The individual repeats words ( or points to pictures) as the audiologist' s voice gets softer and softer. The faintest level, in decibels, at which 50% of the two-syllable words are correctly identified, is recorded as the Speech Reception Threshold (SRT). A separate SRT is determined for each ear.
Tests of word recognition attempt to evaluate how well a person can distinguish words at a comfortable loudness level. It relates to how clearly one can hear single-syllable (monosyllabic) words when speech is comfortably loud. Examples of words used in this test are "come", "high", "knees", "chew." In this test, the audiologist' s voice (or a recording) stays at the same loudness level throughout. The individual being tested repeats words (or points to pictures). The percentage of words correctly repeated is recorded for each ear.
Thus, a score of 100% would indicate that every word was repeated correctly. A score of 0% would suggest no understanding.
Word recognition is typically measured in quiet. For specific purposes, word recognition may also be measured in the presence of recorded background noise that can also be delivered through the audiometer.
How to Interpret an Audiogram
The audiogram is a graph showing the results of the pure-tone hearing tests.
Pitch or frequency
Each line from left to right represents a pitch or frequency in Hertz (Hz) starting with the lowest pitches on the left side to the very highest frequencies tested on the right side. The range of frequencies tested by the audiologist are 125 Hz, 250 Hz, 500 Hz, 1000 Hz, 2000 Hz, 4000 Hz and 8000 Hz. If you are familiar with a piano keyboard with the low notes at the left end and the high notes at the right end, the audiogram is similar. 250 Hz on the audiogram is the same as the "middle C" key on the piano.
Examples of sounds in everyday life that would be considered "low frequency" are : bass drum, tuba, vowel sounds such as "oo" in "who".
Examples of sounds in everyday life that would be considered "high frequency" are: a bird chirping, a triangle playing, consonant sounds such as "s" in "sun."
If we were to compare a flute playing and a tuba playing, we' d say the flute was primarily high frequency (high pitches) and the tuba was primarily low frequency (low pitches).
If we were to compare the sound of "f" as in "fly" to the sound of "m" as in "moon," we' d say the "f" was primarily high frequency (high pitch) and the "m" was primarily low frequency (low pitch).
Loudness or intensity
Each line on the audiogram from top to bottom represents loudness or intensity in units of decibels (dB). Lines at the top of the chart (small numbers starting at minus 10 dB and 0dB) represent soft sounds. Lines at the bottom of the chart represent very loud sounds.
Examples of sounds in everyday life that would be considered "soft" are : a clock ticking, whispering, or the consonant sound "t" in the word "too".
Examples of sounds in everyday life that would be considered "loud" are: a lawnmower, a car horn, or the vowel sound "o" as in the word "poke"
If we were to compare the sound of a jackhammer to the sound of a vacuum cleaner, we' d say the jackhammer was "loud" and the vacuum cleaner was "soft".
If we were to compare the sound of "s" as in "spot" to the sound of "ah" as in "spot", we' d say the "s" was "soft" in comparison to the vowel "ah".
If we were to compare "normal conversational loudness level" (typically 60 dB) to "whispering" (typically 30 dB), we' d say that whispering is soft and conversation is loud. For examples of other loudness levels.
Some audiograma are also divided into sections showing the severity of hearing loss.
As the audiologist tests your hearing, the results are recorded on the graph. At each frequency tested, the "O" represents the softest tone you can hear in your right ear and the "X" represents the softest tone you can hear in your left ear.
If the "X' s" and "O' s" all fall in the -10dB to 15 dB range, your hearing lies in the normal range. If the "X' s" and "O' s" all fall in the 16 dB to 25dB range, you have a slight/minimal loss. If the "X' s" and "O' s" all fall in the 31dB to 51dB range, you have a moderate loss. If the "X' s" and "O' s" all fall in the 91dB and above range, you have a profound loss.
The audiogram configuration may be flat; sloping down showing better hearing in the low frequencies; rising showing better hearing in the high frequencies. The configuration may be symmetrical, showing the same hearing loss for both ears; or,asymmetrical, showing a different hearing loss configuration for each ear.
Once the audiogram is completed, the audiologist computes the pure tone average for each ear. It is the average of hearing thresholds at 500, 1000, and 2000 Hz, which are considered to be the major frequencies for speech. The pure-tone average represents the degree of hearing loss in decibels. It is not a percentage.
Example:
Average loss = 28 dB (mild loss)
45 dB (moderate loss)
Other Audiologic Procedures
There are a variety of other audiologic procedures that assess the auditory system and determine the presence of hearing loss. They are sometimes used independently and sometimes used to complement the standard audiologic test battery. They help to supplement information from behavioral testing or to resolve conflicting information from behavioral testing. They are auditory evoked potentials, otoacoustic emissions testing, and acoustic immittance measures.
Auditory Evoked Potentials
Electrodiagnostic test procedures give information about the status of neural pathways. These procedures are used with individuals who are difficult to test by conventional behavioral methods. They are also indicated for a person with signs, symptoms or complaints suggesting a nervous system disease or disorder.
Auditory brainstem response (ABR) is an auditory evoked potential that originates from the auditory nerve. It is often used with babies. Electrodes are placed on the head (similar to electrodes placed around the heart when an electrocardiogram is run), and brain wave activity in response to sound is recorded.
Otoacoustic Emissions (OAE)
Otoacoustic emissions (OAE) are inaudible sounds emitted by the cochlea when the cochlea is stimulated by a sound. When sound stimulates the cochlea, the outer hair cells vibrate. The vibration produces an inaudible sound that echoes back into the middle ear. The sound can be measured with a small probe inserted into the ear canal. Persons with normal hearing produce emissions. Those with hearing loss greater than 25-30 dB do not.
Acoustic Immittance Measures
Acoustic immittance measures are a battery of tests including tympanometry, acoustic reflex, and static acoustic impedance.
Tympanometry introduces air pressure into the ear canal making the eardrum move back and forth. The test measures the mobility of the eardrum. Tympanograms or graphs are produced which show stiffness, flaccidity, or normal eardrum movement.
We all have an acoustic reflex to sounds. A tiny muscle in the ear contracts when a loud sound occurs. The loudness level in decibels at which the acoustic reflex occurs, and/or the absence of the acoustic reflex, gives diagnostic information that aids in identifying location of the problem along the auditory pathway.
Through static acoustic measures , the physical volume of air in the ear canal is measured. This test is useful in identifying a perforated eardrum or the openness of ventilation tubes.
Balance Assessment
Our sense of balance is determined by our visual system, the inner ear, and our sense of movement via muscles (kinesthetic sense). When these systems don' t work together and function properly, we become dizzy.
Dizziness is a symptom. Any disturbance in the inner ear, with or without hearing loss or ringing in the ears (tinnitus), may cause a feeling of dizziness. Dizziness can be caused by disease such as Meniere' s Disease, by small calcium deposits in the inner ear, drugs which are toxic to the vestibular (balance) system, head trauma, and other conditions not necessarily related to the vestibular system.
Balance system assessment is conducted to detect pathology with the vestibular or balance system; to determine site of lesion; to monitor changes in balance function; or, to determine the contribution of visual, vestibular, and proprioceptive systems to functional balance.
Vestibular or balance system assessment is indicated when a person has nystagmus (rapid involuntary eye movement), complaints of vertigo (dizziness) balance dysfunction, gait abnormalities, or when pathology/disease of the vestibular system is suspected.
Visual reinforcement audiometry (VRA) is the method of choice for children between 6 months and 2 years of age. The child is trained to look toward (localize) a sound source. When the child gives a correct response, e.g., looking to a source of sound when it is presented, the child is "rewarded" through a visual reinforcement such as a toy that moves or a flashing light.
Conditioned play audiometry (CPA) can be used as the child matures. It is widely used between 2 and 3 years of age. The child is trained to perform an activity each time a sound is heard. The activity may be putting a block in a box, placing pegs in a hole, putting a ring on a cone, etc. The child is taught to wait, listen, and respond.
With both of these methods, sounds of different frequencies are presented at a sound level that children with normal hearing can hear.
It is ideal if the child will allow earphones to be placed on his or her head so that independent information can be obtained for each ear. If the child refuses earphone placement or earphone placement is otherwise not possible, sounds are presented through speakers inside a sound booth. Since sound field screening does not give ear specific information, a unilateral hearing loss (hearing loss in only one ear) may be missed.
www.asha.org
Insurances accepted
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