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If you have been suffering from gradual hearing loss, it is possible that you may be suffering from a rare condition called otosclerosis. This is a condition which affects the middle section of the ear, which is the section found behind the eardrum and which is predominantly filled with air. There are three bones within the middle ear section and these are called the malleus, the incus and the stapes.

In order for people to have a full range of hearing, there is a need for the bones in the middle ear to be able to move around freely. When someone is suffering from otosclerosis, they suffer from bone material that grows around the bones, usually from the foot of the stapes. This additional growth restricts the movement of the bone and this will reduce the amount of sound that is moved over to the cochlea. The growth of these additional bones is gradual, so it is not a condition that people will wake up with one morning. Rather, there will be a gradual loss of hearing over time, which can be described as a conductive hearing loss.

In most cases of otosclerosis, it is just the stapes which are impacted upon but in some cases, other parts of the ear are affected. Also, if the condition is allowed to manifest over time, it may have an impact on other parts of the ear. It has been known to impact on the cochlea and on the nerves within the cochlea. If this turns out to be the case, there is a chance of nerve cells being damaged which will impact on the impulses being sent to the brain. In this situation, the type of hearing loss is referred to as a Sensorineural loss of hearing. With otosclerosis, both ears can be affected, but it is not uncommon for just one ear to be affected.

Causes of otosclerosis

Even with a considerable amount of research and study into the condition, the exact cause of otosclerosis is yet to be determined. What is known is that the bones in the ear, like all bones, are living tissues which have cells that are evolving and developing all the time. This means that bones are always changing, breaking and remodelling back together. When someone suffers from otosclerosis, there is an issue at the remodelling stage. For whatever reason, a new bone is not forming properly, and this causes the abnormality in the ear, even if research is yet to find the reason for this abnormality.

Research has indicated that genes may be an issue in otosclerosis, which means that otosclerosis may be inherited. It has been found that of the people that suffer from otosclerosis, around 2 in 3 of the sufferers have family members who also carry the condition. This is a lot, but it still leaves one third of sufferers who have no family links to the condition.

There are also studies into the notion that a virus, notably the measles virus, provides a link for the cause of otosclerosis. Findings indicate that the amount of people who have been diagnosed with otosclerosis has decreased since the development of the vaccination against the measles virus.

Research is ongoing into whether there is a case to make that people with otosclerosis in their family history and who then suffer a viral infection are more likely to see the onset of otosclerosis. Research is also ongoing as to whether there is a link between otosclerosis and fluoride. This is down to the fact that the number of recorded UK cases of otosclerosis dropped when fluoride was added to standard drinking water. This is a theory which is under debate and not everyone thinks that there is a genuine link.

Who suffers from otosclerosis?

The standard rate of otosclerosis sufferers in the United Kingdom stands at about 1 or 2 people for every 100. It is said that the initial onset of otosclerosis begins between the ages of 15 and 35, although it can develop at an earlier age. It has been found that women are twice as likely to suffer from otosclerosis as men. While pregnancy is not seen as a cause of otosclerosis, it has been found that the conditions caused by otosclerosis are more notable during pregnancy, making the symptoms more notable and easier to recognise or diagnose during pregnancy.Given the gradual development of otosclerosis, people may have the condition for many years before noticing or reacting to change, which means that people in their 50s or older are more likely to notice the condition.

The key symptoms of otosclerosis

Quite simply, the key symptom of otosclerosis is the loss of hearing. The hearing loss can be quite mild, and many people will dismiss, perhaps considering it part of the aging process or as an outcome that is not worth bothering about. However, the condition will become worse over time, which means that early diagnosis is of benefit. Although otosclerosis can affect one ear at a time, both ears have been known to be affected. Although most sufferers will find that the loss of hearing is mild, some will notice that the loss of hearing can come upon them quickly. If otosclerosis is left untreated, the sufferer could end up with permanent hearing loss. This is why it is necessary to look out for the signs and to seek treatment for otosclerosis.

Other symptoms that can also signify otosclerosis include speaking quietly and hearing better when there is backgrounds noise. Some people find that they can hear conversations better in a pub with background chatter than they can when sitting in a quiet room with one other person. This condition is known as paracusis.

How is otosclerosis diagnosed?

For otosclerosis to be diagnosed, you need to be seen by an ear, nose and throat specialist and specialist hearing tests can pinpoint the type of hearing loss that you have. The tests can be carried out quickly and with no pain to the patient. In some cases, otosclerosis can be diagnosed through CT scanning.

Otosclerosis treatment

A hearing aid is commonly the first form of treatment for otosclerosis, providing sufferers with amplification.

In more serious cases or when otosclerosis has been persistent, surgery can be undertaken. This is when the stapes are replaced with a plastic or metal bone. In some patients, this can be a risky procedure which may place their hearing and other parts of their ear at risk, but every patient is different. It is necessary to ask your specialist what your individual chances of success are in this situation.