Audiology

There are three main types of hearing loss depending on the area of the auditory pathway that has been affected. The three main types are explained below.

Sensori-neural hearing loss

This type of hearing loss can be caused by damage or a defect of the inner part of the ear. This may be due to natural wear and tear, noise exposure, congenital, genetic or viral. A sensori-neural hearing loss is usually a permanent hearing loss and in most cases surgical or medical intervention cannot restore the hearing.

Conductive hearing loss

This type of hearing loss can be caused by damage or a defect of the outer or middle part of the ear. This may be due to a number of causes including malformation of the ear, wax, infection or middle ear effusion. This type of hearing loss affects the transmission of the sound from the outer ear through the middle ear and in to inner ear. In most cases a conductive hearing loss can be successfully treated by an ENT consultant.

Mixed hearing loss

This type of hearing loss is a mixture of a sensori-neural hearing loss with an element of a conductive hearing loss. In most cases, if ENT intervention is not possible, hearing aids can be fitted.

Our service provides the most up to date sophisticated digital hearing aids. The Audiologist will discuss and demonstrate the style of hearing aid that will best suit your hearing level.

We primarily provide behind-the-ear hearing aids. Connected to your hearing aid will either be a custom fit ear mould or a slim tube, which fits neatly into your ear. The most appropriate set-up will be discussed by the Audiologist as not all hearing losses are suitable for both types.

During the hearing aid fitting appointment, the Audiologist will fit your hearing aid, ensuring a comfortable and secure fit. The hearing aid will be programmed using your hearing test results, and further tests will be performed to ensure the hearing aid is providing the correct level of amplification. The Audiologist will discuss the use, care and maintenance of your hearing aid and ample time will be allowed to practice inserting and removing the hearing aid from your ear.

The Audiologist will explain what to expect from using a hearing aid in the short and long term. It is likely to take a number of weeks, perhaps even months, before you become fully acclimatised to your hearing aid. At first, everything may sound quite loud, tinny or un-natural however by persevering with your hearing aid everything begins to sound more natural.

Your hearing can sometimes seem dull when you take your hearing aid off, however this is just because you have become accustomed to hearing much better with the hearing aid in. Using a hearing aid will not make your hearing any worse, although your hearing may deteriorate overtime.

After a period of time a follow-up will be arranged to check on your progress with your hearing aid. This may be through a posted questionnaire (stamped addressed envelope provided) or a face to face appointment, depending on which is most appropriate.

A bone conduction hearing aid can be a good solution if your hearing loss is due to problems in your outer or middle ear. This is because it bypasses these parts of the ear and transmits sound directly into your inner ear. This can be highly beneficial if you suffer from conductive or mixed hearing loss especially when a conventional hearing aid cannot be used.  A bone anchored solution can also be beneficial for those with a profound hearing loss in one ear also known as single-sided deafness.

We provide a comprehensive bone conduction hearing aid assessment and fitting service for suitable candidates who have been referred to the audiology department following an ENT consultation. All of these assessments are carried out at University Hospital of North Durham and Darlington Memorial Hospital by our specialised bone conduction hearing aid team.

The initial assessment will take approximately 1 hour and 15 minutes to complete. During this assessment a full history will be taken and hearing and speech tests will be performed to determine suitability. If suitable, a trial of a bone conduction hearing aid will be arranged to determine if this is the appropriate treatment. If so, the results are returned to ENT to arrange implantation of the abutment.

Approximately 4-6 weeks after implantation of the abutment, the bone conduction hearing aid is fitted. Once fitted, we provide a full aftercare and review service.

When a person hears with both ears the brain can tell where a sound is coming from. But when you have unilateral hearing loss or deafness in one ear judging where noise is coming from is a challenge. Known as the head shadowing effect, having only one working ear can interfere with the surround sound experience normally associated with binaural hearing or hearing with two ears. In the past, a person with unilateral hearing loss would have to position themselves toward the sound source to try and make up for this shadowing.

CROS systems have been designed for single sided deafness (SSD) to help reduce this shadow effect. Unfortunately not everyone with a single sided hearing loss will be appropriate for a CROS or BICROS hearing system. This is why all patients who may be suitable for a CROS system are referred for a full CROS assessment. This ensures they are provided with the most appropriate aiding and amplification for their hearing loss.

CROS stands for Contralateral Routing of Signal. A CROS hearing system takes the sound from the side which has little or no hearing (the bad ear) and will digitally transmit it to the better ear wirelessly. This means the person will not hear sound in the "bad ear ", but they will be more aware of sounds from that side, therefore helping to reduce the shadow effect. The system requires the person to wear two hearing aids, a transmitter on the bad ear and a receiver on the better ear.

A BICROS hearing aid works in the same as the CROS system, but is used where a Patient also requires amplification to their better hearing ear.

CROS/BICROS systems are only available at the University Hospital North Durham or Darlington Memorial Hospital sites via referral from an ENT Consultant.

Sound waves vibrate the air which then travel down the ear canal to the tympanic membrane (the ear drum). The vibrations travel across the ear drum and along the bones of the middle ear to the inner ear (the cochlea). Vibrations initiate the hair-like cells in the cochlea to send nerve impulses to the brain, which interprets these nerve messages as sound.

Anything that reduces or prevents the sound signal before it reaches the brain can cause some level of hearing loss. Hearing loss can be mild, moderate, severe or profound. The types of the hearing loss can be described as:

• Conductive hearing loss is a problem with the outer or middle ear. This can be temporary or permanent
• Sensorineural hearing loss is permanent and can occur if the cochlea (inner ear) isn't working properly
• Mixed hearing loss is when conductive and sensorineural losses occur together

Visual reinforced audiometry (VRA)

This test is suitable for infants from six months to two years old. If successful, we can measure the level of your child's hearing across the speech range in each ear separately.

The child is presented with a sound from one of the loudspeakers from the left or right, as the child turns to the sound they are presented with a visual reward in the form of an illuminated cartoon on a TV screen. In order to obtain ear specific hearing thresholds the child may wear headphones or have small insert phones placed in the ear canals to generate the stimulating sounds.

Play audiometry

Play audiometry is suitable for pre-school children of 20 months to five years old (developmentally). The child must be able to understand simple instructions and commands.

A game is played in which the child must perform an action when a sound is heard. This could take the form of putting toy people in a boat or stacking rings on a tower. The child may listen to sounds from a loudspeaker, wear headphones or small insert phones into the ear canals during the test. Sounds at various frequencies are presented to the child and gradually reduced in loudness.

Pure tone audiometry (PTA)

School age children are generally able to manage this test. Tones of varying frequency and intensity are played through headphones or insert phones. The child must press a hand held button for as long as they can hear a sound. The loudness of the sounds are reduced until the child stops responding, this is the threshold of hearing. The threshold of hearing is plotted creating an audiogram.

Tympanometry and acoustic reflexes

We may carry out a test to see if there is any congestion behind your child's eardrums. This involves placing a small tip into the edge of the ear and puffing a small amount of air into the ear canal. The test takes a matter of seconds to perform, however your child needs to remain still during the test. Part of the test may involve introducing a short sound into the ear.

Otoacoustic emissions (OAE)

This is the same test that most newborn babies have as part of the new born hearing screen. Your baby needs to be settled and the room very quiet for this test which takes just a few minutes. The audiologist will explain what the results mean after the test.

Auditory Brainstem Response (ABR)

Your baby will need to be asleep for this test and the test room kept very quiet throughout the test. The test may take up to 2 hours. Please bring everything you need to settle your baby / child to sleep once they have been prepared for the test. We can also perform this test under general anaesthetic if requested by your Ear Nose and Throat doctor.

If a hearing loss is identified, appropriate support and management will be provided. Depending on the nature of the hearing loss, this may involve a monitoring period or fitting of a hearing aid.

If your child is found to have a temporary hearing loss, (for example, glue ear, causing a conductive hearing loss) then we may choose to monitor their hearing over a period of time.

If a persistent or permanent hearing loss is identified then we will discuss the use of amplification through a hearing aid. We will refer your child to an ENT consultant for their medical opinion and we work closely with our sensory support team to enable effective communication to assist in development both at home and in the school.

There are many different models of hearing aid available in various shapes, sizes, colours and the way in which they process the sound. We will assess the most appropriate style of hearing aid for each individual, looking at their hearing loss and any additional factors. Most hearing aids fit behind the ear. A custom earmould is manufactured to help hold the hearing aid in place and to carry the sound into the ear canal.

Allow time to adjust to the hearing aid/s. Try and build up use until they are worn consistently for all of the day or as recommended by the audiologist.

Please contact us if you notice any changes in ability to hear with or without the hearing aids. Review of the hearing aid/s is performed after fitting and then regularly until 16 years of age, when they will transition into the adult services.

How do I look after the earmould?

Keep it clean by washing it regularly in the following way:

• Detach the ear mould from the hearing aid
• Remove any debris which is blocking the tube
• Wash the ear mould in warm soapy water
• Dry it thoroughly and remove any water in the tube by blowing it out using the 'puffer' provided
• Re-attach the ear mould to the hearing aid

Changing the tubing

You should change the tubing when:

• It becomes hard, discoloured, or twisted
• There is a hole or split in the tube
• Tubing is too short and needs to be re-measured
• The tubing is blocked
• If you haven't been shown how to replace the tubing ask at your next appointment

When should I contact the department for new earmoulds?

• If the hearing aid is whistling when in the ear
• The earmould has clearly become outgrown, so that you can see a gap between the edge of the earmould and the ear
• The earmould is split or damaged
• The earmould is uncomfortable

Do we need to come to the hospital to collect the new earmoulds?

Your audiologist should have shown you how to trim the tube to the right length. If not, please ask at your next appointment. When you are confident at trimming the tubing we can post the new earmoulds home to you.

Earmould safety

Please be aware that earmoulds are small objects which can sometimes be a choking hazard.

Please contact the department if you:

• Require more batteries
• Require spare tubing
• If you need a new mould
• If you feel the hearing aid may be faulty
• If you feel the hearing has changed with or without the hearing aid

All vestibular assessments are carried out at Darlington Memorial Hospital by our specialised vestibular assessment team. The vestibular assessment can take approximately 90 minutes to complete. During the assessment you may be instructed to look at lights and move your head and body into various different positions. Part of the test may require some warm and cool air (caloric test) to be delivered into your ear canals to evaluate the function of each balance organ. You may be asked to wear some goggles containing infrared cameras (VNG) which will enable us to record your eye movement during each part of the assessment. We may also test all 6 semi-circular canals with the vHIT system and the otolith organs with the VEMP system.

The results of the assessment will be analysed and put into a report for your ENT specialist, along with any concerns that may have been identified. If appropriate, the specialist audiologist may discuss some balance rehabilitation techniques and/or make an appropriate referral for some balance management. The results of the assessment will be sent back to your ENT specialist for review in their ENT clinic.

We offer balance rehabilitation at University Hospital North Durham and Darlington Memorial Hospital. Balance rehabilitation is a programme of rehabilitation which includes the administration of a set of graduated and customized exercises. It may also, where appropriate, include additional components such as education, breathing and relaxation exercises, counselling and gentle aerobic activity.

Other factors may also be addressed to optimise rehabilitation, such as management of anxiety and avoidance behaviours, which may require onward referral, as well as recognising abnormalities in posture, gait, joint range of motion and general physical conditioning, which may also require input from a physiotherapist or other suitable clinician as needed.

We have developed close links with the falls team, physiotherapy, social services, local support groups and many more external rehabilitation services and further information can be given as required.

In order for us to maintain balance, the brain gathers information from the eyes and vestibular system and combines this with what is felt through our joints, muscles and pressure sensors throughout the body. Our vestibular systems are situated within each inner ear and their function is to detect movement and where we are in space. Each vestibular system consists of three fluid-filled tubes called semicircular canals and two otolith organs. Each of these canals are aligned at different angles to each other and connected to the otolith organs enabling them to detect movement in any direction. As you move your head, the fluid within these canals moves, sending information to the brain about how fast and how far you have moved.

What is dizziness?

The word dizziness is used to describe any feeling of unbalance. This can range from a severe spinning sensation called vertigo, to mild unsteadiness or light-headedness. Dizziness occurs when the information gathered from the balance system disagrees with what the brain recognises as normal. There can be many reasons for this

If you are concerned about any dizziness or imbalance, please see your GP who can refer you to the Ear, Nose and Throat (ENT) department, who can arrange any other investigations that might be necessary. This may include a referral to Audiology for a further assessment and to see what can be done to help.

There is a difference between listening and hearing, listening is a skill and like any skill it needs confidence and practice. We can offer information to help improve those listening skills and improve confidence.

Managing sudden hearing loss

Adaption to change, the grief cycle, discussion of rehabilitation including equipment and any further management.

Effective listening devices

Addressing the correct equipment to the problems faced by the individual.

Equipment

Loop systems, doorbells, telephones, streaming devices and alerting devices

Initial assessments can be face to face or telephone and can take up to 1 hour to complete. During the assessment the specialist audiologist will take an in depth history of your concerns and needs and decide on the most appropriate management strategy. Subsequent appointments may be required depending on your circumstances and these can be arranged if required.

Our specialist audiologists have developed close links with other professionals within health and the community who specialise in other areas of rehabilitation, for example physiotherapy, the falls service, social services, lip reading or tai-chi classes. During an assessment it may be beneficial for you to access some of these services and we will discuss this with you.

Tinnitus is unique to the person experiencing it. But ultimately it is the sensation of hearing a sound when there is no external source for that sound. Someone with tinnitus may hear ringing, buzzing, hissing, whistling or other noises. Tinnitus can be there all the time or come and go. The volume of someone's tinnitus can vary from one episode to the next.

Sound sensitivity is a condition when people experience the sounds of everyday life as intrusively loud or uncomfortable or even painful. Sometimes this is also referred to as Hyperacusis. For some, it is a minor annoyance. Others find it difficult to live with and withdraw from social and professional activities. This isolation can make the problem worse. Therapy can help to address fears and anxieties and sound therapy can help to re-build a tolerance for sound.

If you are concerned about your tinnitus or sensitivity to sound, please see your GP who can refer you to the Ear, Nose and Throat (ENT) department, to arrange a hearing test and any other investigations that might be necessary. If your tinnitus or sound sensitivity is impacting your quality of life, the ENT department will refer you to Audiology for a further assessment and to see what can be done to help.