What is Audiology?

You may be asking yourself, “what is Audiology?”  Audiology is a small niche field that most are unfamiliar with unless they need an Audiologist themselves. Despite its discretion the field of Audiology is extremely dynamic and diverse.

Audiology by Definition

The term audiology can be broken up into two subsets of the word, ‘audio’ which means hear, and ‘logy’ which means the study of. So in essence Audiology is the study of hearing and its mechanisms, including balance, as both hearing and balance are controlled by the inner ear.

Audiology has therefore been outlined as the health profession concerned with the prevention, identification, and evaluation of hearing and balance disorders. Audiologists are not only instrumental in diagnosing these disorders, they also provide habilitation or rehabilitation to individuals with these deficits in efforts to improve quality of life.

What type of studies can be done?

The ear is made up of multiple sections including the outer ear, middle ear, inner ear, and the central auditory pathways. Since the auditory system has multiple sections a number of studies are needed to analyze where the hearing or balance deficits are coming from in efforts to establish the appropriate treatment and rehabilitation plan.

Types of Hearing Studies

Complete Audiological Evaluations

Complete Audiological Evaluations are comprehensive hearing evaluations for all age ranges. This test is used to determine the severity and type of hearing loss. It includes a series of tests like pure tone, speech, and admittance testing. It is often the first step towards determining the treatment course for a variety of hearing and balance disorders.

The Weber test

The Weber test is an audiometric assessment that can indicate whether a hearing loss is coming from the outer ear, middle ear or inner ear. The patient is presented with a tone through bone conduction and is asked to lateralize the sound as left, right, or center. This test allows the Audiologist to further diagnose the nature of the patient’s hearing loss. This is critical in patients for whom the medical history does not clearly reveal the etiology of the hearing deficit, and helps to guide the medical or surgical recommendations.

Eustachian Tube Function Test

Eustachian Tube Function Test analyzes the Eustachian tube that connects the ear and the throat to allow for equalization of pressure in the middle ear. The Eustachian Tube test assesses the function of this tube to ensure that the ear is equalizing normally to atmospheric pressure. This test is the only objective way to measure Eustachian tube function, particularly in the presence of normal hearing and normal admittance results.

Ultra-High Frequency Testing

Ultra-High Frequency Testing requires specialized equipment and headphones to test pure tone frequencies from 9k-16kHz which are not typically tested on the standard Complete Audiological Evaluation. The Ultra High Frequencies are assessed in the cases of subjective tinnitus, ototoxic monitoring, and/or concern of hearing difficulties in the presence of normal hearing. This test gives us information about damage to the audiological system prior to any detection of hearing loss on the standard audiogram. It would be important to know this information in the treatment of tinnitus, for adjusting ototoxic medications, and the need for Aural Rehabilitation.

Otoacoustic Emissions (OAE) Testing

Otoacoustic Emissions (OAE) Testing is a physiological assessment of the inner ear. Echoes from the sensory organ for hearing are being monitored to determine cochlear function. This test aids in the diagnosis of the degree and type of hearing loss and is especially useful in estimating hearing loss in difficult to test populations.

Auditory Brainstem Response (ABR) Testing

Auditory Brainstem Response (ABR) Testing is a physiological assessment of the auditory nerve and hearing structures within the brainstem. It can aid in the differential diagnosis of cysts or tumors on or within the neural auditory pathway. It is also used to estimate levels of hearing in difficult to test or unreliable patients. Potentials from the auditory pathway are being monitored through superficial electrodes placed on the skin and ears.

Central Auditory Processing Testing

Central Auditory Processing Testing is an interactive assessment of central auditory function. In some cases hearing levels may not be the cause for communication or hearing difficulties. There are times where the brain is aware that there is sound but the message may not be clearly processed at the level of the brain.  In these cases, this testing may be indicated to help guide rehabilitation.

Tinnitus Evaluations

Tinnitus Evaluations are used to assess the patient's tinnitus through a series of tone tests to determine the best course of treatment for a patient's tinnitus relief.

Types of Balance Studies

Videonystagmography (VNG)

Videonystagmography (VNG) is used to aid in the diagnosis of a variety of balance disorders. Through the use of video goggles we are able to closely monitor eye movements to help in the differentiation of peripheral and central balance disorders helping to guide further assessment and/or treatment. The patient will be given a list of instructions to follow prior to the day of testing.

Electrocochleography (EchoG) Testing

Electrocochleography (EchoG) Testing is a physiological assessment of the inner ear to aid in the diagnosis of endolymphatic hydrops and/or Meniere's disease. Action potentials from the cochlea are being monitored through superficial electrodes placed on the skin and ears.

Vestibular Evoked Myogenic Potential (VEMP) Testing

Vestibular Evoked Myogenic Potential (VEMP) Testing is a physiological assessment of the inner ear to aid in the diagnosis of semicircular canal dehiscence. Muscular potentials from the sternocleidomastoid muscle are being monitored through superficial electrodes placed on the forehead and neck.

Fistula Testing

Fistula Testing is a way of diagnosing the Perilymphatic Fistula of the inner ear through the use of video eye goggles and pressure testing. This helps to guide in the treatment of the dizzy patient.

Rehabilitation Options

The Audiology Arena

Audiologists can work with varied populations throughout the age range, including pediatric, adult, and geriatric individuals at all stages of development. The environments that audiologists work in are diverse as well and can include:

• Medical centers like hospitals and Ear Nose and Throat (ENT) clinics.
• Rehabilitative centers like nursing homes and homes for the developmentally delayed.
• Educational settings like mainstream public and private schools as well as schools for the deaf.
• Industrial settings, including construction worksites or transportation sites where noise exposure is a risk.
• Corporate environments like manufacturers for hearing aids, implants, and testing equipment.
• Private practice offices that treat ear disorders.
• Federal Agencies like the US army and the Veteran Affairs hospitals.
• College and University settings working as a clinical director, supervisor, or professor.
• Remote Audiology services supporting patients remotely to diagnose or rehabilitate their ear disorders via telehealth and telephonic services.
• Surgical intraoperative monitoring using neurodiagnostic test to monitor the nerves during head and neck surgical procedures.

In all these roles, the goal is unified: to be of service to patients and improve their quality of life by assessing, rehabilitating, and protecting their hearing and balance health.

More information can be found on https://en.wikipedia.org/wiki/Audiology and https://www.asha.org/public/hearing/types-of-tests-used-to-evaluate-hearing/