Hearing loss is partial or total inability to hear sound in one or both ears. Hearing loss makes communication difficult, therefore, audiological evaluations are done to check one’s hearing.
Audiological tests are done by Audiologist who are healthcare professionals in the identification, diagnosis, evaluation and prevention of hearing and balance related disorders.
There are various diagnostic audiological tests done by Audiologists to check auditory function, they are:
· Tuning fork test
· Puretone audiometry
· Speech audiometry
· Impedance audiometry
· Oto acoustic emission test
· Brain stem response audiometry
· Special tests
TUNING FORK TEST:
Tuning fork tests are simple tests these allow one to distinguish between conductive and sensorineural hearing loss. The tuning fork of 512 Hz is the most accepted and set frequency which is used to assess the hearing. There are mainly two tests; Weber and Rinne Test.
An otoscope is a magnification device used by medical practitioners to observe and examine the condition of ear canal and tympanic membrane (ear drum).
The otoscope is used to check if the patient has presence of earwax, foreign body, pus, ear infections if any and view of the tympanic membrane.
PURE -TONE AUDIOMETRY:
A Pure tone audiometry test is a measurement taken of an individual’s hearing. It is a diagnostic test used to monitor the hearing level of a patient.
This test uses an equipment called audiometer which helps the audiologist to determine the degree of hearing in patients.
Soundproof rooms are used as test rooms to control and avoid any disturbance during the test.
The audiologist provides test instructions like earphone placement, about the tone and how to respond before proceeding to the test. The patient is instructed to indicate presence of tone by raising the hand or verbalizing “yes”. The audiologist assesses the threshold of hearing at different frequencies. Audiologists then determine the hearing by the patient’s response behavior. The result of hearing evaluation is then explained in an audiogram which is a graph that shows presence or absence of hearing loss. Then Audiologists counsel the patients according to their Audiogram.
Speech audiometry is described as a method for assessing the state or ability of auditory system of an individual, using speech as response evoking stimuli. The pure tone audiogram provides only a partial picture of patient’s ability to understand speech. Therefore, speech stimuli are provided during testing.
This diagnostic assessment is used to test the function of the middle ear. After getting the information from case history, the audiologist observes the ear with an otoscope.
Tympanometry is done after that. Tympanometry gives information about the ear canal and middle ear. An Impedance Audiometer is used to do the test. The use of Impedance audiometry test is recommended when the patient has middle ear pathology.
Otoacoustic emissions are acoustic signals generated by the inner ear.
OAE testing allows the audiologist to understand how the outer hair cells of inner ear are working.
OAE tests are clinically important because they are simple, non-invasive tests for hearing defects in newborn babies and infants.
OAE also helps in differential diagnosis of hearing loss.
AUDITORY BRAINSTEM RESPONSE:
The ABR is used to check the presence or absence of a hearing disorder and site of disorder. ABR testing is used in infants who fail OAEs and are at risk for hearing loss or neurological problems. ABR in newborn screening is a screening or follow up technique used to check the hearing sensitivity in infants. Audiologists place a set of electrodes on patient’s head, scalp and earlobe. Electrodes measure brains wave activity to see how brain their respond to various sounds.
ABR is used for adults also to co relate pure tone audiometry results and to understand site of lesion in some cases.
Special tests are also referred to as site of lesion test as this gives information to the audiologist about the site of lesion of hearing loss.
For more information contact us – Better Speech & Hearing Clinic, HSR Layout, Bangalore.
Call- 9606404343, firstname.lastname@example.org