Our staff performs comprehensive hearing testing on patients of all ages, including infants. Testing is done by a variety of methods appropriate for the patient’s age and ability.
An audiogram, or hearing test, is an assessment of a patient’s hearing which is recorded on a graph. The audiogram demonstrates how loud a sound, tone, or word needs to be presented before it can be heard by a patient. This is checked from low tones to high tones and particular attention is paid to those frequencies important to the hearing and understanding of speech. The results are charted and compared to what is considered normal hearing.
During the testing, the patient wears earphones and is asked to raise their hand or press a button when a sound is presented. The sounds are presented at a variety of levels to determine the softest level which can be heard. Each ear is assessed separately. A device can be placed behind the ear to help differentiate between middle ear or inner ear (cochlea) disorders.
When small children are tested, they are asked to perform a simple task such as placing a chip into a box or pointing to a picture when the sound or word is heard. The audiologists are skilled in choosing tasks appropriate for children of all ages and cognitive levels and in making them comfortable during the exam.
When testing infants, sound is presented via a speaker rather than an earphone, and when the child turns toward the source he or she is rewarded by the appearance of a lighted puppet. This is known as visual reinforcement audiometry (VRA). As with the other tests, this is continued until the softest threshold can be determined.
When these behavioral methods of testing can not be performed, other methods of hearing testing are available. Otoacoustic emission testing (OAE) is used to determine the cochlear, or inner ear, function. Sounds presented to the ear, usually in the high pitch range, will elicit a response from the cochlea that can be measured. This is a valuable screening study for newborns and for patients who are unable to respond by conventional means.
Auditory Brainstem Response testing (ABR) is also a method of determining the threshold of hearing. Clicking noises presented through an earphone allow measurement of the electrical response of the auditory system, from the cochlea to the brain. The intensity of the clicks is reduced to the lowest level of response. The ABR can also be used to determine the ability of the auditory nerve to conduct sound energy. An audiologist may order this test with certain individuals who have tinnitus in one ear or asymmetric hearing loss.
Middle Ear Function Testing:
The audiologists at York ENT offer services to gauge the function of the middle ear. One of these is tympanometry, or immitance testing. This measures the ventilation of the middle ear, the mobility of the eardrum (tympanic membrane), and can determine the presence of a tympanic membrane perforation or fluid in the middle ear. A small probe placed into the ear canal is used for this test.
Benign Paroxysmal Positional Vertigo (BPPV) is a common source of dizziness. It is estimated that approximately 20% of all patients with vertigo have BPPV. BPPV occurs when otoconia, or tiny calcium deposits, normally present in the inner ear, migrate to the semicircular or balance canals making them inappropriately sensitive to gravity. As a result, when patients turn the affected ear down, a severe sensation of vertigo develops. Often this happens when the patient rolls over in bed.
In a Dix-Hallpike test, a patient lies down on his or her back, with the head turned to the side. The patient’s eyes are then observed for about 30 seconds. A positive Dix-Hallpike test occurs when the patient’s eyes appear to be moving, usually in a rotatory fashion.
Following diagnosis, patients with BPPV are treated with repositioning exercises by our audiologists. These maneuvers are designed to allow the calcium deposits to leave the balance canals and alleviate the condition.