Hearing Test


A hearing test provides an evaluation of individual’s overall hearing function, which is performed by a qualified Audiologist.

Prior to hearing test certain forms need to be filled for patient’s personal information at the reception, then an audiologist carried out a verbal questionnaire to know about the medical history, family history and related things to the hearing problems.

The audiologist inspects/ looks into the patient’s ears by using an Otoscope. This instrument is used to see the ear canal and the ear drum to rule out ear wax obstructing the canal or any signs of a medical issue that calls for referral to ENT doctors.

All hearing test are carried out at a soundproof room (Acoustic Chamber/Booth).Different test are designed for different populations.

For Children

A range of different techniques are used to detect hearing problems. Some hearing tests are mainly used for children, including:

Free field audiometry (FFA)

This is a hearing test in the form of a game and is typically used for children between 2 to 4 years. Every time the child hears a tone he or she has to dropping a block in a bucket or stuff like that. Tones are presented at different pitches through headphones or speakers. This test relies on the cooperation of your child to sit still and listen.

Visual Reinforcement Audiometry (VRA)

This hearing test is typically used for infants over 6 months of age who are not yet developmentally ready for FFA. This test takes advantage of your baby's natural head turn to look for sounds in his or her environment. The audiologist will train your baby to turn towards sounds, using of toys that light up as a visual reward. Sounds are presented through earphones and/or speakers.

Behavioural Observation Audiometry (BOA)

BOA is a test used to observe hearing behaviour to sound when VRA is not possible. This is often used for infants less than 6 months of age or who are developmentally not able to turn their head towards a sound

Oto Acoustic emissions (OAE)

A soft probe tip is placed into the ear canal. Sounds are sent through the probe tip into the ear. When the ear detects the sounds, the cochlea emits a response back that is measured by a sensitive microphone in the probe tip. This response is called an otoacoustic emission (OAE). When OAE responses are present, it often means that the hearing is near-normal and if OAE responses are absent, it suggest many things which includes middle ear fluid and/or permanent hearing loss.

Brainstem Evoked Response Audiometry (BERA) and Auditory Steady State Response (ASSR)-

For BERA/ASSR testing, two electrodes are to be placed on the forehead and one behind each ear of the child. Sounds are played through earphones that fit inside child’s ears. This testing is done regularly for infants who do not pass their newborn hearing screening. It is safe and non-invasive but it can only be completed while your child is sleeping. ABR testing is typically done under sedation. However, some tests, such as pure tone audiometry, speech perception and tympanometry can be used to test adults and as well as children.

Adults

There is different battery of test to determine adult hearing. They are described below step by step.

Tuning fork test

A tuning fork is placed on the patients forehead and on the mastoid bone to rule out conductive hearing loss, which caused by sounds not being able to pass freely into the inner ear, or sensori-neural hearing loss where the inner ear or hearing nerve is not working properly.

Pure tone audiometry

Pure tone audiometry (PTA) tests the hearing of both ears. During PTA, a machine called an audiometer is used to produce sounds at various volumes and frequencies (pitches). You listen to the sounds through headphones and respond when you hear them by pressing a button.

Speech perception

The speech perception test, also sometimes known as a speech discrimination test or speech audiometry, involves testing your ability to hear words without using any visual information. The words may be played through headphones or a speaker, or spoken by the tester. Sometimes, you are asked to listen to words while there is a controlled level of background noise.

Tympanometry

During tympanometry, a small probe seals your ear canal and the machine gently changes the pressure in your ear canal. The test can be used to confirm whether there is any fluid behind the eardrum and can indicate if the Eustachian tube is working normally. Tympanometry measures the movement of the eardrum and the pressure behind the eardrum.

Hearing test results

The results of Pure Tone Audiometry hearing tests are plotted on a graph called an audiogram. An audiogram is used to record the measurements of different volumes and frequencies (pitches) of sounds you are able to hear. As well as showing a comparison between your ears, an audiogram can also help to determine what type of hearing loss you have, if any.

The type of hearing loss you have is important because it determines what help or treatment is most suitable for you.