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Simple Surgery Hearing Tests
Advice to patients:
Examination
Your GP or practice nurse will first ask about any symptoms you may be experiencing, such as:
 pain or discharge (fluid)
 tinnitus – noise in one or both ears
 vertigo (dizziness)
 hearing loss
 previous, relevant medical problems
Your ear will be examined using an instrument called an auriscope, also known as an otoscope. An
auriscope is a small hand-held torch with a magnifying glass which allows the doctor to see the
eardrum and the passageway that leads to it from the outer ear. It can be used to look for:
 discharge – fluid coming out of the ear
 a bulging eardrum – indicating that there is infected fluid in the middle ear
 a retracted eardrum – indicating uninfected fluid in the middle ear (glue ear)
 perforated eardrum – a hole in the eardrum, with or without signs of infection
 ear wax or foreign bodies that might be blocking the ear
Your GP may also carry out simple tests using their voice to help determine the extent of your
hearing loss. If there are any concerns, you or your child may be referred to an ear, nose and throat
(ENT) specialist for further tests.
Hearing tests in children
A range of different techniques are used to detect hearing problems. Some hearing tests are only
used for children, including:
 automated otoacoustic emissions (AOAE) tests – a computer attached to a small earpiece
plays quiet clicking noises and measures the response from your child's ear
 automated auditory brainstem response (AABR) tests – sensors are placed on your
child's head and neck to check the response of their nerves to sound played through
headphones
 play audiometry tests – sounds of different volumes and frequencies are played to your
child and they carry out a simple task when they hear them
Read more about how hearing and vision tests for children are carried out.
However, some tests, such as pure tone audiometry, speech perception and tympanometry (see
below) can be used to test adults and well as children.
Hearing tests in adults
There are a number of different ways to test adult hearing. Some of these are briefly described
below.
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
The eardrum should allow as much sound as possible to pass into the middle ear. If sound is
reflected back from the eardrum, hearing will be impaired.
During tympanometry, a small tube is placed at the entrance of your ear and air gently blown down
it into the ear. The test can be used to confirm whether the ear is blocked, most commonly by fluid.
Whispered voice test
The whispered voice test is a very simple hearing test. It involves the tester blocking one of your ears
and testing your hearing by whispering words at varying volumes. You will be asked to repeat the
words out loud as you hear them.
Tuning fork test
A tuning fork produces sound waves at a fixed pitch when it is gently tapped and can be used to test
different aspects of your hearing.
The tester will tap the tuning fork on their elbow or knee to make it vibrate, before holding it at
different places around your head.
This test can help determine if you have conductive hearing loss, which is hearing loss 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.
Bone conduction test
A bone conduction test is often carried out as part of a routine pure tone audiometry (PTA) test in
adults.
Bone conduction involves placing a vibrating probe against the mastoid bone behind the ear. It tests
how well sounds transmitted through the bone are heard.
Bone conduction is a more sophisticated version of the tuning fork test, and when used together
with PTA, it can help determine whether hearing loss comes from the outer and middle ear, the
inner ear, or both.
Hearing impairment may be very variable in severity but can cause severe communication difficulties
leading to profound educational, social and psychological problems. As well as ensuring effective
screening problems for children, it is essential to consider and arrange appropriate tests for any child
or adult with possible hearing impairment.
Simple Surgery Hearing Tests
Advice for GPs performing tests:
The hearing level (HL) is quantified relative to 'normal' hearing in decibels (dB), with higher numbers
of dB indicating worse hearing. Hearing loss is often described as:
 Normal hearing: less than 25 dB in adults and 15 dB in children.
 Mild hearing loss: 25-40 dB.
 Moderate hearing loss: 41-65 dB.
 Severe hearing loss: 66-90 dB.
 Profound hearing loss: 90+ dB.
100 dB hearing loss is nearly equivalent to complete deafness for that particular frequency. A score
of 0 is normal. It is possible to have scores less than 0, which indicates better than average hearing.
Simple testing of hearing in the GP surgery may be used for initial assessment to determine if further
investigation or treatment is indicated.
Whispered voice test
•
A simple and accurate test for detecting hearing impairment. There is some concern regarding
the lower sensitivity in children and the overall reproducibility of the test, particularly in primary
care settings.[1]
•
The examiner stands at arm's length (0.6 m) behind (to prevent lip-reading) the seated patient
and whispers a combination of numbers and letters (for example, 4-K-2), and then asks the patient
to repeat the sequence.
•
The examiner should quietly exhale before whispering to ensure as quiet a voice as possible.
•
If the patient responds incorrectly, the test is repeated using a different number/letter
combination. The patient is considered to have passed the screening test if they repeat at least three
out of a possible six numbers or letters correctly.
•
Each ear is tested individually, starting with the ear with better hearing. During testing the nontest ear is masked by gently occluding the auditory canal with a finger and rubbing the tragus in a
circular motion.
•
The other ear is assessed similarly with a different combination of numbers and letters.
Masking the ear
•
Masking the ear: simply putting a finger in one ear is insufficient. Howeverf the tragus is rubbed
at the same time, this will provide sufficient masking in most tests except for use of a loud voice.
Alternatively, continuously rubbing a piece of paper between the thumb and index finger produces a
consistent broadband sound. To test for loud noises, a Bárány noise box needs to be used.
Tuning Fork testing
1. Rinne's test
•
This uses tuning forks of 512 Hz but those of 256 Hz may be more accurate. A heavy tuning fork
is preferable as a light one produces a sound that fades too rapidly.
•
It produces a sound level of 90 dB when struck against the knee or elbow.
•
To test air conduction, hold the tuning fork directly in line with the external auditory canal.
•
When testing bone conduction, place the flat end of the stem of the tuning fork against bone
immediately superior and posterior to the external canal, using firm pressure (loudness varies by up
to 15 dB with different pressures). Hold the patient's head steady with your free hand.
•
When air conduction is louder than bone conduction it is reported as Rinne-positive. Rinne's
test will reliably detect a conduction defect with an air bone gap of at least 30-40 dB. However it is
no substitute for pure-tone audiometry.
2. Weber's test
•
A 512 Hz tuning fork is placed in the midline of the patient's forehead. If the sound is louder on
one side than the other, the patient may have either an ipsilateral conductive hearing loss or a
contralateral sensorineural hearing loss.
This advice and further information are available from
http://www.patient.co.uk/doctor/Hearing-Tests.htm and
http://www.nhs.uk/Conditions/Hearing-tests/Pages/How%20it%20is%20performed.aspx