Deafness - Diagnosing hearing loss
- Introduction
- Signs of hearing loss
- Causes of hearing loss
- Diagnosing hearing loss
- Treating hearing loss
- Preventing hearing loss
- ‘20 years ago, deaf people would have found it difficult to get into this sort of job’
- 'Through performing, I've managed to grow as a person'
See your GP if you are having problems with your hearing. They will examine your ears and carry out some simple hearing tests.
You might also wish to visit the Action for Hearing Loss website for an online hearing test.
Ear examination
During an ear examination, an instrument with a light at the end called an auriscope (or otoscope) is used to look for anything abnormal including:
- a blockage caused by earwax, fluid or an object
- an ear canal infection
- a bulging ear drum – indicating that there is infection inside the middle ear
- fluid behind the ear drum, known as glue ear
- a perforated ear drum – a hole in the eardrum
- a collapsed ear drum
- skin collected in the middle ear (cholesteatoma)
Your GP will ask you if you have any pain in your ear and when you first noticed the hearing loss.
Referral to a specialist
Your GP may refer you to an ear, nose and throat (ENT) specialist or an audiologist (a hearing specialist). The specialist will carry out further hearing tests to help determine what is causing your hearing loss and recommend the best course of treatment.
Some of the hearing tests that you may have include:
- a tuning fork test (sometimes performed by your GP)
- pure tone audiometry
- bone conduction test
These tests are described below.
Tuning fork test
A tuning fork is a Y-shaped, metallic object. It 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 sensorineural hearing loss where the inner ear or hearing nerve is not working properly.
Pure tone audiometry
Pure tone audiometry tests the hearing of both ears. During the test, a machine called an audiometer produces sounds at various volumes and frequencies (pitches). You listen to the sounds through headphones and respond when you hear them by pressing a button.
Bone conduction test
A bone conduction test is often carried out as part of a routine pure tone audiometry test in adults. It is used to check if you have sensorineural hearing loss by testing how well your inner ear is working.
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 pure tone audiometry, it can help determine whether hearing loss comes from the outer and middle ear (conductive hearing loss), the inner ear (sensorineural hearing loss), or both.
Newborn Hearing Screening Programme (NHSP)
After your baby is born, they will be given a number of routine health checks, including a hearing test. The test is part of the NHS Newborn Hearing Screening Programme (NHSP), and it will be carried out within the first few weeks of your baby's birth.
A test that is commonly used to check a baby’s hearing is the otoacoustic emissions (OAE) test. The test involves placing a tiny earpiece into the outer ear. If possible, it will be carried out while your baby is asleep.
The earpiece emits small sounds and checks for a corresponding "echo" from the ear. If your baby's ear is working normally, the echoes should be produced in a part of the ear known as the cochlea. A computer is used to record and analyse the reaction sounds.
If there is no response, it does not necessarily mean that your child has a hearing impairment, although further tests will be needed to determine the cause.
About 15% of newborn babies will need further testing and one to two babies in every thousand will have some level of hearing loss in one or both ears.
Levels of hearing loss
Very few people with hearing loss hear nothing at all. There are four different levels of hearing loss, which are defined by the quietest sound that you are able to hear, measured in decibels (dB). These are described below.
Mild deafness
If you are mildly deaf, the quietest sound that you can hear is between 21 to 40dB. Mild deafness can sometimes make hearing speech difficult, particularly in noisy situations.
Moderate deafness
If you are moderately deaf, the quietest sound that you can hear is between 41 to 70dB. You may have difficulty following speech without using a hearing aid.
Severe deafness
If you are severely deaf, the quietest sound that you are able to hear is between 71 to 90dB. People who are severely deaf usually need to lip-read or use sign language, even with the use of a hearing aid.
Profound deafness
If you are profoundly deaf, the quietest sound that you can hear is more than 90dB. People who are profoundly deaf can often benefit from a cochlear implant. Other forms of communication include lip reading and sign language
Read more about treating hearing impairment, including different types of hearing aids and sign language.
© Crown Copyright 2009
