What is otosclerosis?
Otosclerosis progresses slowly. It usually occurs between the ages of 20 and 40. The changes often begin long before the symptoms appear. Over the years, inflammation-like processes develop on the petrous bone. This is the bone in which your inner ear is located: The healthy bone dissolves, creating spongy tissue that later hardens.
Hearing loss occurs when the remodeling processes begin in the area of the so-called oval window, the transition from your middle ear to the inner ear. The stirrup is movably attached here. This ossicle transmits the sound vibrations to the fluid in the inner ear. The resulting movement stimulates the sensory cells located there, which in turn transmit the stimulus to the auditory nerve.
If you suffer from otosclerosis, tissue grows around the footplate of the stapes and literally walls it in. The elastic suspension of the stirrup becomes ossified and can no longer move freely. As a result, it can no longer transmit sound, or only imperfectly. Your hearing gradually deteriorates. They become hard of hearing (so-called conductive hearing loss) or experience ringing in the ears (tinnitus). If the hair cells in the inner ear are destroyed by otosclerosis, this can even lead to deafness. Usually both ears are affected.
Otosclerosis: causes and risk factors
Around one in ten people show changes in the bone structures in the middle and inner ear. However, symptoms of otosclerosis only develop in around one percent of the population. Women are affected twice as often as men. The cause of the disease is not fully understood. Experts suspect that some viral infections can trigger changes in the inner ear – such as measles, mumps and rubella. Other possible causes:
- Autoimmune reactions of the body, when it mistakenly fights its own tissues, are also suspected as a cause.
- Hereditary factors also play a role: around every second person affected has at least one family member with the same disease. In addition, otosclerosis is more common in the white population than among people of other skin colors.
- Hormonal influences can also be partly responsible for the development of otosclerosis. The first symptoms or a noticeable deterioration often appear in women when they are using hormonal contraception or are pregnant.
Symptoms: Diminishing hearing
If you suffer from otosclerosis, your hearing will gradually deteriorate. Initially, the symptoms occur in one ear. As the disease progresses, both ears are affected in around 70 percent of cases. affected. Typical symptoms:
- Some people with otosclerosis hear better in a noisy environment (e.g. on a busy road) than in a quiet one. The explanation for this is that those affected hear disturbing noises more quietly, especially at lower pitches
and secondly, their dialog partners speak louder when there is noise in the environment.
- Some sufferers develop ringing in the ears (tinnitus), which usually sounds deep.
- In some cases, if the organ of balance located in the inner ear is also affected, dizziness can also occur.
The increasing ossification restricts the mobility of the stapes more and more. A deterioration can manifest itself with symptoms similar to a sudden loss of hearing and initially improve again. But if left untreated, the hearing loss progresses. In rare cases, the hair cells in the inner ear can also be destroyed, resulting in complete deafness.
It is often the case that the earlier the disease occurs, the faster it develops.
Otosclerosis: Diagnosis with us
If you have the impression that your hearing is deteriorating, we are the right place to go. However, it is not easy to diagnose otosclerosis at an early stage.
We will first ask you whether
- you have recently had a viral or bacterial infection.
- family members are hard of hearing or deaf.
- you have previously suffered from similar complaints.
- you have recently had an accident.
We use tympanometry to examine the pressure in the middle ear and the mobility of the eardrum. This allows us to determine whether there is fluid in the middle ear, for example, or whether the mobility of the ossicles is impaired. In most cases, there is initially no change in the eardrum or middle ear. We can look into the ear canal with a microscope (otoscopy). If an inflammation is the cause of the hearing problems, the ear canal and eardrum will be clearly reddened.
However, if you suffer from otosclerosis, your ear canal and eardrum will appear normal. In rare cases, we can recognize a reddish area on the eardrum, the so-called Schwartze sign.
Stapedius reflex measurement for otosclerosis
We use the stapedius reflex measurement to examine the function of the middle ear. This provides us with information about the mobility of the stirrup (lat. stapes). Otosclerosis leads to reduced mobility – this is known as a conductive hearing loss.
Hearing test for otosclerosis
By means of a hearing test, we can determine how advanced your hearing loss is and from which part of the ear the hearing impairment originates. To do this, we strike the tuning fork, hold it in front of the ear and place it on different parts of the skull bone. You say when you can no longer hear the vibration. In the case of otosclerosis, where the ossification is located exclusively in the middle ear, sound conduction is impaired. Then the sound waves cannot be transmitted in the outer or middle ear. In the case of sensorineural hearing loss, the hearing impairment originates in the inner ear, auditory nerve or brain (capsular otosclerosis).
Further examinations for otosclerosis
A so-called speech audiometry with various speech tests shows whether you already understand spoken words less well.
In some cases of suspected otosclerosis, further examinations are available to us:
- With a computer tomography of the ear region, we can detect possible changes in the bone and the ossicles.
- A balance test indicates problems in the vestibular system.
- In some cases, magnetic resonance imaging is also carried out.
Otosclerosis: prevention, early detection, prognosis
You cannot specifically prevent otosclerosis, for example through your lifestyle. However, if members of your family already suffer from it, it is advisable to have your hearing checked regularly by us. We can examine the sound conduction in your middle ear and detect any otosclerosis at an early stage. You should also do this if you experience hearing problems or tinnitus. If otosclerosis is detected at an early stage, you can have it treated surgically and prevent possible secondary symptoms such as deafness in good time.
If you develop otosclerosis and have it treated early, the prognosis is favorable: in over 90 percent of cases, surgery can significantly improve hearing or completely eliminate hearing loss. If the operation proceeds without complications and the eustachian tubes of both ears are clear, air travel is not a problem.
Otosclerosis: surgery improves hearing
If left untreated, ossification progresses steadily. A hearing aid can compensate for the increasing hearing loss. The only helpful treatment for otosclerosis is surgery performed under general anesthesia: stapedotomy.
Stapedotomy for otosclerosis
Stapedotomy is the treatment of choice. In around 90 percent of operations, it improves the patient’s hearing. We only remove the stirrup leg, while the footplate remains in place. We drill a small hole in it and insert a prosthesis, which we attach to the anvil. The prosthesis can transmit sound vibrations again without interference and thus improve hearing.
Two weeks after the operation you will usually be able to work again. As a side effect, dizziness may occur for a few days after the procedure, but this will subside. Sometimes the inserted prosthesis slips out of place and the operation has to be repeated. In individual cases, the operation worsens hearing.