Diagnostic Audiologic Evaluation
If you or your child has been referred for a diagnostic audiologic evaluation, it means that hearing loss needs to be ruled out or further examined. The diagnostic audiologic evaluation may be indicated for individuals who did not pass an initial hearing screening.
The evaluation is done to determine if a hearing loss is present, and if so, to detail the type and severity of the hearing loss. It also may provide insight in to the cause of the hearing loss as well as provide guidance for the audiologist in making appropriate treatment recommendations.
What Tests Will Be Done?
The specific tests done during the evaluation will depend on the patient’s age, and what is known already about their hearing status. These various tests will the degree of hearing loss, the type of hearing loss, and the conditions of the ear canal and middle ear. The audiologist will also determine if the hearing loss is conductive (middle or outer ear problem) or sensorineural (inner ear problem or central processing difficulty of the brain).
A diagnostic audiologic evaluation includes pure-tone testing, bone-conduction testing, and speech testing.
Pure-tone Air and Bone Conduction Testing
Pure-tone air conduction testing determines the quietest tones that a person can hear at different frequencies, both low and high. Bone conduction testing is similar to pure-tone air conduction testing. A different type of headphone is used during bone conduction testing, and the results help the specialist determine if the hearing loss is originating from the outer/middle ear or from the inner ear.
A speech reception threshold (SRT) test is often used with older children and adults to confirm the results of a pure-tone test. This test determines the lowest level at which the patient can recognize words or speech stimuli. A word recognition test determines the percentage of understanding in quiet and in noise for loud speech.
The audiologist also performs otoscopy (examining the ear canal) and tympanometry (test of the middle ear) to determine the condition of the ear canal and the middle ear. Otoacoustic emission testing (DPOAE) allows the audiologist to understand how the outer hair cells of your inner ear are working.