Conductive hearing loss

Conductive hearing loss is usually associated with obstructions to the outer or middle ear and can also be caused by certain diseases, this type of hearing loss will affect all frequencies and the loss usually isn’t severe. The person suffering from conductive hearing loss will usually be able to be helped surgically or has great success when using a hearing aid.

Sensorineural hearing loss

This type of hearing loss is usually brought about by damage to the sensory hair cells or nerves of the inner ear, hearing loss due to this will normally be more profound than conductive hearing loss and it usually affects only certain frequencies. Even when wearing a hearing aid the person affected by sensorineural hearing loss may still have great difficulty in hearing certain sounds.

Central hearing loss

This type of hearing loss is usually done by damaging the nerves of the central nervous system; this can be either in the brain itself or the pathways leading to the brain.

Mixed hearing loss

This type of hearing loss is a combination of conductive hearing loss and sensorineural hearing loss, this means that the person can suffer from problems relating to both the middle and outer ear as well as the inner ear.

What can be done to help those hard of hearing?

There are many things that can be done to help the hard of hearing, people who have been hard of hearing or deaf for a number of years will usually have learnt to lip read or even sign. They may also wear a hearing aid to help them hear more clearly and there are several steps a person can take to make life easier for them.

• Always make sure the person knows when you are going to speak by facing them.
• Make sure you talk in good lighting conditions.
• Try to have your conversation away from distractions, such as heavy traffic or loud background noise.
• Don’t mumble or use a lot of slang words.
• Speak in a clear voice but don’t shout at the person.
• Remember that just because the person cant hear it doesn’t affect their intellectual capacity.

From birth to 4 months of age

At this stage your baby should:

• Be startled when they hear a sudden loud noise such as a shout, hand clap or dog barking nearby?
• When asleep does your baby wake up at the sound of loud noises?
• If your baby is crying does he/she stop crying if they hear your voice while you’re still out of site, or quieten down if you play music?
• By the time your baby is around 4 months old he/she should be turning their head towards sounds they hear.

4 to 8 months of age

At this stage your baby should:

• Does your babies eyes widen at the sound of a voice or loud noise?
• Does your baby notice sounds that are outside of the peripheral vision?
• Does your baby enjoy a sound mobile, rattle or any other toy which makes noises?
• Around the age of 6 months your baby should be gurgling or babbling back to people who speak to them.
• Around the age of 6 months your baby should be making different sounds when babbling.

8 to 12 months of age

At this stage your baby should:

• Your baby should be responding to soft noises and turning their head towards them.
• Your baby should be able to respond to their own name.
• Their voice should alter in pitch when babbling.
• Your baby should be adding constants to their babbling, such as m, b, p and g.
• Your baby should respond to music by bouncing and jigging up and down.
• Your baby should understand the word no.

Of course every child develops at a different pace and the above is only a very rough guide, your child may respond earlier or a little later to any of the above but it is usually around the ages stated above. If you suspect that your child may have problems with their hearing then consult your doctor or health care visitor.

What causes the condition?

It is a very rare condition with almost 95% of all reported cases being spontaneous but experts don’t really know what causes the condition and the condition is more common in people between the ages of 30 and 60. a very small percentage of the cases reported are thought to be caused by a hereditary disease called Neurofibromatosis Type II, people affected this way are normally younger people who may also be affected by other types of neuroma.

What are the symptoms of acoustic neuroma?

The most common symptom is gradual hearing loss in the side that is affected by the tumour, as the tumour grows the hearing will deteriorate and sufferers of the disease report distorted or muffled sounds. Eventually total hearing loss may occur and there may also be a feeling of pressure and tinnitus in the side which is affected.

How is the condition diagnosed?

Most people with the disease will be referred to an ENT specialist by their doctor; they will be suffering from symptoms such as hearing loss, dizziness and tinnitus. The ENT specialist will take a full medical history and they will organise hearing tests and probably balance tests.

They will then conclude from these tests whether or not they think you are suffering from acoustic neuroma, if so then the next step will be to do an MRI scan. The MRI scan involves passing high frequency radio waves through the body to produce a picture, the whole process will usually take just a few minutes and is painless.

How is the condition treated?

Treatment will depend on your health in general, how big the tumour is and the results of any other tests taken. All options will be considered and there isn’t any rush for treatment as the tumour is very slow growing, treatment options include:

• Observation – if the tumour is only very small then the ENT specialist may decide just to keep an eye on it and see how things progress.
• Microsurgery – this is a very successful treatment for the condition and the tumour will be removed and no further treatment will be necessary.
• Radiotherapy – small doses of radiation may be used to stop the tumour from growing, radiotherapy can usually be done in one visit and recovery is usually quicker than with microsurgery.

How the conventional hearing aid works

The difference between this type and the conventional type is that the conventional type will normally fit into the ear canal and works by delivering sounds through a process known as air conduction. This is achieved by sounds passing through the ear canal to the ear drum which then vibrates, this is what the term air conduction means.

Vibrations are then passed onto three small bones in the middle ear which in turn carries them to the cochlea, fluid that surrounds the cochlea then affects the tiny hair cells that run along the length of the cochlea which generates signals in the auditory nerve. The signals that travel along the nerve go to the brain and the brain interprets them as the sound we hear.

How the bone conductive hearing aid works

The bone conductive hearing aid still amplifies sound but the sound is not passed into the ear canal, instead the sound is carried through the bone in the skull, this process is called bone conduction and is where the hearing aid gets its name from.

In order to hear the sounds are sent directly from the vibrating part of the bone conduction hearing aid through the bone in the skull straight to the cochlea totally bypassing the outer and middle ear. This method is not as good as hearing through air conduction but they are a great option for people who can’t use a traditional hearing aid.

Who can benefit from a bone conductive hearing aid?

Sometimes people can’t wear a conventional hearing aid for reasons such as having ear infections on a regular basis or they have eczema, their ear canal may be small or they have problems with their ear canal. A bone conductive hearing aid is more suitable for these types of people, the hearing aid is also more suited to people who suffer from conductive hearing loss.

How is this type of hearing aid worn?

There are two main parts to this type of hearing aid with one part being worn on the body and the other part being the actual bone conductor fitted to a removable headband and this holds the conductive part closely to your head. Due to the tightness of them however then can become uncomfortable and can cause headaches and soreness of the skin due to the tightness.

Questions you should ask

A hearing aid is very costly so you should make sure you know what options are available to you and ask any questions you can think of before committing to buying a hearing aid. Some of the questions you should ask are:

• Does your medical insurance cover the cost of the hearing aid?
• Does the quote for the hearing aid cover the cost of the test?
• Does the quote include any follow ups that you might need?
• If you need a hearing aid for both ears is there a discount?
• Will you be able to see the dispenser quickly if you have problems in the future with the hearing aid?
• Never sign anything unless you know exactly what you’re getting for your money.

Always makes sure you know what it entails when buying your hearing aid, usually the hearing aid will be covered under a warranty and this can be anything from one to three years then after this period you will have to pay for repairs. As they can be so expensive it is often worth taking out insurance on your hearing aid for loss or damage and you should check with your insurance company to make sure it is covered under any existing policy you may have.

Choosing a hearing aid

There are many different types of hearing aid and they usually fall under the category of digital or analogue, there are very small hearing aids which fit entirely into the ear and cannot be seen or there are ones that are fitted behind the ear. Not all types are suitable for everyone for example the smaller hearing aid with many features could be fiddly for someone with large hands, the smaller types might also not be suitable for someone suffering from severe hearing loss.

Features of hearing aids

With the advancements being made today hearing aids now come packed with many features these range from being able to change the hearing aid to different environments, for example a noisy club to a quiet room, to automatically controlling feedback from the hearing aid. Of course digital ones such as these are very expensive so you should take into account if you would really benefit from a feature packed hearing aid.

The external part is very similar to a hearing aid and can be worn either clipped onto the clothing or worn on the head; sound then translates into electronic signals and is then sent to the internal part. The internal part is something which is implanted into the ear, into the cochlea, it picks up the electrical signals from the sound processor to the auditory nerve, and these signals are then recognised as sounds by your brain.

Who are cochlear implants suitable for?

Cochlear implants however aren’t suitable for everyone, if you are profoundly deaf in both ears particularly from sensorineural deafness as this is due to damage to the tiny hairs in the cochlear and in order for the implant to work correctly then the hearing nerve has to work even though the cochlear doesn’t. Also if you were born deaf then the implants might not work because in order to make sense of the sounds you hear through the implant then you need some previous memory of sound.

If you developed your deafness when you were older then you will have already developed language skills and the operation could help you, the earlier you have it after becoming deaf the more benefit you would get from it.

What does the assessment for the implant entail?

Your doctor and the ENT specialist will be the ones that confer with you to decide if the implant would be beneficial to you, if it is decided that you would benefit from it then you will be sent to a specialist centre where the implant can take place. At the centre you will also see an audiological scientist, a speech and language therapist, a clinical psychologist and a social worker who specialises in helping deaf people. Some of the tests you could have during the assessment are:

• A trial with the most recent hearing aids.
• Audiological tests to see if you have any hearing.
• A CT scan which will help to determine if there is anything to stop you having an implant.
• Tests for your balance.
• Tests to see if your hearing nerve will respond to electrical signals.
• Psychological tests.

During the assessment you will also be given counselling as to what to expect from the implant and once you have decided to have it then the waiting list will be around one month to a year.

Problems with the outer ear

Any blockage in the external ear canal can cause deafness or hard of hearing, the most common of these is a build up of wax. The healthy ear needs wax to keep it healthy and this is normally when under control, however sometimes for various reasons the wax can build up and then it can cause hearing loss. You should never try to remove stubborn wax yourself but instead see your doctor who can syringe them for you to remove the wax.

Otitis externa

This condition happens when the skin of the ear canal becomes inflamed; this can be caused by a skin condition known as eczema or by a scratch to the ear. Although it doesn’t usually cause hearing loss or deafness you can have a full feeling in your ear and the ear itself is very painful.

Problems with the middle ear

Otitis media

This condition is usually caused by a bacterial infection and causes the Eustachian tube to become blocked, when the tube becomes blocked then the ear will fill up with fluid and this causes intense pain and hearing loss. The condition is usually found in children though anyone of any age can suffer from it.

Otosclerosis

This condition will usually affects women more than men starting from around the age of 30 and is known to run in the family. It is a condition that is caused by a bony overgrowth of the stapes; the stapes stretches across the middle ear and if you suffer from this condition deafness is gradual. Hearing aids can be beneficial up to a point but usually an operation called a stapedectomy is recommended, this involves the insertion of a tiny peg to replace the stapes.

Damaged ossicles

If you suffer serious head trauma or a serious infection then the ossicles which are tiny bones in the middle ear can become damaged and this can cause hearing loss, sometimes babies are born with malformed ossicles, however they can be repaired with an operation.

Perforated eardrum

A perforated eardrum can result from the infection otitis media if it is left untreated, perforated eardrum is also caused by several other factors such as injuries to the head, very loud noises such as explosions or by poking a q-tip too far into the ear canal. Hearing loss caused by a perforated eardrum is usually only temporary and the perforation will normally heal itself.

Tinnitus

This is a noise which is heard in the ear almost constantly and can range from a whistling sound, ringing, rushing or buzzing and there are many reasons for its cause. Unfortunately there isn’t much that can be done for tinnitus but sufferers do learn to cope with it and most times don’t even notice it being there. While it doesn’t cause loss of hearing as such, it can be sometimes extremely difficult to hear due to the loudness of the sounds in the ear.

How do genes cause problems?

Sometimes genes can change and this is called mutation, when a gene mutates it doesn’t function as it should, genes can cause deafness by altering the protein needed for hearing and when this happens it causes deafness.

Genes are very complex but put simply the chances of deafness being caused by genes depends on if the mutation of the gene is dominant or recessive. If a dominant mutation occurs to a single copy of a gene then this will cause deafness and the affected gene can either come from the mother or the father.

The range of deafness can vary greatly from mild deafness to profound deafness or it might even not be noticeable but the person will carry it. A recessive gene will only cause deafness if both the mother and father have passed on the gene and this is the most common type of genetic deafness.

Getting help if you are worried about passing on deafness genetically

If either you or your partner or both of you are deaf or hard of hearing and you are worried that you might pass deafness on genetically to children then you should talk with your doctor about it.

Your doctor will probably suggest that you see a genetic counsellor, a genetic counsellor specialise in genetics and they will be able to explain fully and easily the chances of you passing deafness onto any children you might have.

What does the counselling involve?

The counsellor will be able to explain the ways in which deafness can be inherited, they will also be able to tell you about any tests that you can take and make it as easy as possible for you to make up your own mind about the risks.

They will take a full family history from the both of you and will probably want to know of any audiological tests that you both have had with regards to your deafness. Very often the counsellor will be able to tell you why your deafness was inherited or explain why they can’t be sure if that is the case, they might also suggest that you have a genetics test.

What is a genetics test?

A simple blood sample is all that is needed for the test and this will determine if the gene needed for hearing is mutated, by identifying the gene they might be able to get a more accurate diagnosis of what caused your deafness and also determine the chances of passing your deafness onto your children. If a mutated gene is found, then other family members will be offered testing to see if they carry the gene too.

Behind the ear hearing aids

This type will normally sit behind the ear and have an ear mould which fits inside your ear, they are connected by a plastic tube. This is a very common type of hearing aid and the one which is widely used and available on the NHS. For those people who have only very mild hearing loss there is a newer version of the behind the ear hearing aid called an open ear fitting and they use a small earpiece instead of the ear mould.

In the ear hearing aids

This type of hearing aid fits directly in the ear and all the working parts are fitted into it, they vary in size from ones which are visible in the ear to ones which are so small that they fit all the way inside your ear canal and are barely noticeable. However this type isn’t suited to those with very narrow ear canals or those who are profoundly deaf.

How do digital hearing aids work?

The digital hearing aid takes a signal from the microphone and transfers this into data, there is a tiny computer fitted into the digital hearing aid and this computer then translates the data, due to the great advancements in digital hearing aids they can be finely adjusted and are able to process sounds very precisely.

Digital hearing aids have the advantage over analogue ones in that they are able to reduce background noise which can help greatly. The more expensive digital hearing aids will have controls for finer adjustments with different settings for different situations and conditions.

Many of them will actually be able to adjust themselves to conditions without you having to control them at all but of course these are the top of the range models. Some of the more expensive hearing aids also have what is called feedback cancellation; this means that it will reduce the whistling noise that many people complain of hearing.

They also have wide dynamic range compression which means that you can adjust several channels; these channels can be adjusted to your particular hearing loss and ensures that you hear sounds at levels that are comfortable to you. However this type of hearing aid is a more advanced model and you could well expect to pay up to £3,500.

What is earwax and why is it important?

The correct name for earwax is cerumen and it consists of oil and sweat being secreted from the glands in the outer ear canal. Ear wax is both antifungal and antibacterial and it is essential in keeping the ears clean and healthy, however some people feel they should poke out the wax but this can lead to problems and can result in a perforated eardrum should you poke too deep or making the situation worse by pushing the wax further down the ear canal onto the ear drum.

Only occasionally does earwax become a problem and then you should always visit your doctor to have your ears syringed and never try to remove the wax yourself.

What causes a blockage due to wax?

Sometimes we get an excess of wax built up in the ear canal, this usually results in a stuffy feeling in the head and some hearing loss depending on the amount of excess wax you have. The reasons for this can be numerous but some of the most common reasons are outlined below.

• Working in a dusty or dirty environment.
• Wearing earplugs continually in your work.
• Your ear canals could be narrow.
• People who wear a hearing aid can suffer from excessive wax build-up.
• Poking your ears with cotton buds or the finger results in the ear producing more wax.
• Older people can get excessive build up of wax.
• Men tend to suffer from excessive build up more than women.

What ear syringing involves

Most doctors now use a pulsed water jet system although the older metal or chrome syringes can still be used, this works by forcing high pressure water into your ear to dislodge the wax. It only takes a few minutes and although it can be a little uncomfortable it isn’t very painful, there are some things your doctor should know before you have your ears syringed and these are:

• If you have had an infection or injury to your ear.
• If you have had surgery on your ears.
• If you have tinnitus or any form of hearing loss before the problem with excess wax.
• If your eardrum may be perforated.
• If you had problems when you had your ears syringed before.