Hearing loss does not automatically mean only hearing quieter. Hearing impairments occur both gradually and suddenly and do not have to affect both ears. Plugs of earwax or middle ear infections can be the cause if sounds are only perceived muffled. Natural aging processes, noise, or inflammation of the inner ear also cause sound not to be transmitted correctly. Symptoms such as dizziness, nausea, and ringing in the ears (tinnitus) can then occur. Audiometry or otoscopy is used to determine the cause and extent of the hearing loss. Not only hearing aids are available for therapy, but depending on the disorder, surgical restoration of the eardrum or an ankle prosthesis is also used.
How common is hearing loss?
Hearing loss is one of the most common sensory disorders. It is estimated that almost half a billion people worldwide are affected, approximately 48 million Americans have some degree of hearing loss. However, old age is by no means the only possible cause of hearing loss. It can also be caused by heredity, noise damage, trauma, or hearing loss.
Structure of the ear
The human ear is made up of 3 sections: the outer ear, the middle ear, and the inner ear. Outer ear: The outer ear includes the pinna and the external auditory canal. Middle ear: behind the eardrum, there are 3 successive ossicles of the middle ear, which are located in the tympanic cavity. Inner ear: Finally comes the inner ear, which contains our organ of balance, also the cochlea, so-called hair fibers, and nerve pathways that transmit incoming information to the brain. Now, if a sound is heard in front of the human ear, the outer and middle ear transmits the sound further to the inner ear. Thus, the outer and middle ear serves to conduct sound.
Causes/symptoms/progression of different forms of hearing loss
In principle, three types of hearing loss can be differentiated, each of which is accompanied by different symptoms. There are differences as well as overlaps in the possible causes.
Conductive hearing loss
In conductive hearing loss, the ambient sound cannot be transmitted unimpeded through the outer and middle ear to the inner ear. The sound arrives only muffled or not at all, resulting in hearing loss.
Conductive hearing loss most common causes are:
Hole in the eardrum (eardrum perforation): a hole in the eardrum is caused either by direct injuries, such as from a cotton swab or indirectly by rapid changes in air pressure, such as from an explosion or a blow to the ear. The affected person feels a stabbing pain, sometimes dizziness.
Sensorineural hearing loss
In the sensorineural hearing loss, sound vibrations arrive in the middle ear but cannot be processed there and transmitted to the brain.
Sensorineural hearing loss following causes are possible:
Age-related hearing loss: due to aging processes, the auditory nerves and sensory cells increasingly deteriorate and wear out after the age of 50. Affected persons are often first unable to hear high-pitched sounds, and in the later stages, low-pitched sounds as well.
Hearing loss: for no apparent reason, acute hearing loss occurs suddenly, usually on one side, and there are noises in the ears and a feeling of pressure. The cause of hearing loss has not been scientifically clarified, but circulatory and metabolic disorders, as well as viral infections, are discussed. Unilateral deafness may also occur in this context.
Tinnitus is not in itself a type of hearing loss. Rather, it is a sudden or continuous ringing in the ears that often occurs as an accompanying symptom in other conditions such as sudden hearing loss, inflammation of the ears, age-related hearing loss, or exposure to noise. However, in many of those affected, no clear cause can be identified. The ear noises manifest themselves as hissing, knocking, beeping, or droning in the ears, whereby the acoustic perception is not attributable to an external sound source, and in part impair hearing due to their occurrence and volume.
Therapy for hearing loss
The choice of therapy for hearing loss depends primarily on the cause. If, for example, a medication is identified as the trigger, a change may already be sufficient to remedy the problem. For persistent hearing problems, there are several treatment approaches.
Hearing aid and cochlear implant
To treat sensorineural hearing loss, doctors usually prescribe a hearing aid. If this is no longer sufficient, a so-called cochlear implant is usually the therapy of choice. This small electronic device is inserted by means of a surgical procedure and stimulates the auditory nerve directly. Hesitation is not a good idea when deciding on an implant, according to experts. The sooner one decides on it, the better the decline in hearing ability can be slowed down.