The main disorder of the auditory function is deafness. The poor functioning of the ear called hard or hearing impairment. Deafness is not a disease but an accompanying phenomenon of disorders of the ear, auditory nerve or central nervous system. Deafness can occur one or both sides. With single-sided deafness include the directional hearing disturbed: the patient may be difficult to identify where the sound comes from. Heredity is approximately 40-50% the cause of congenital deafness. Whether there is malformation or abnormal predisposition of the inner ear causing deafness from birth, or there is an increasing degeneration of a normal Instance. As a result the decline in hearing acuity will develop in childhood or later in life.
Not only innate forms of hearing impairment or deafness are due to inherited disorders. The construction of the ear, especially during the first three months of pregnancy, very sensitive to the influence of several factors. Although many factors are known to be harmful still new discovered.
Premature birth can cause apart from other factors, on its own hearing. Statistically it has been able to prove that, with special equipment, decrease observed in the auditory acuity is pronounced as hearing counterbalance lower. At birth, a trauma, but especially prolonged oxygen deprivation causes are hearing.
In adolescents and adults ox important other factors. Sound of firearms, disco noise, jet engines, pneumatic hammers, drills and other industrial noise can permanently damage the inner ear.
At deafness distinguish between conduction disorders and disturbances in perception d, all mixed forms may occur. In order to determine what type of hearing loss suffered by the patient, will perform the throat, nose and throat specialist research. All forms of conductive hearing loss can be corrected surgically or with a hearing aid. In the absence of ear canal and middle ear is a new ear canal drilled out in the bone and can be a guidance system to replace the middle ear. Ossicles can be replaced by synthetic material.
In these procedures, the surgeon makes use of a special operating microscope.
Patients with conductive hearing loss are also easily help with a hearing aid, because it requires only enhance the volume. In patients with hearing loss by impairment of cognitive adaptation is difficult out. She does not always lead to a completely satisfactory result, because loss of the ability to distinguish tones can never be completely eliminated.