What are the causes of deafness?

What are the causes of deafness? Aliases:

Hearing impairment, hearing loss, hearing impairment, deafness, hearing impairment.

Departments: Otolaryngology, Pediatric Health Care.

Gong Shusheng. Medical Codex Expert Group.

Chief Physician of Beijing Friendship Hospital.

Director of the Department of Otolaryngology-Head and Neck Surgery, Beijing Friendship Hospital, Capital Medical University, and Chief Expert of the World Health Organization Collaborating Center for Deafness.

The content of this word is original by the Health Medical Codex, and it has been reviewed and proofread three times.

Overview** Symptoms** Prognosis Daily.

Many factors, both congenital and acquired, can eventually cause deafness.

Congenital factors, including genetic factors, maternal infection factors during pregnancy and childbirth, etc., often lead to hearing loss at birth, shortly after birth, and of course, it may also be delayed.

Acquired deafness can occur at any age. For example, the risk of hearing loss increases as we age; The environment or noise is too loud and exceeds the normal tolerance threshold; Noise pollution for a long time, etc.

What are the deaf people?

The ear is divided into three main areas: the outer ear, the middle ear, and the inner ear. Sound vibrates through the eardrum in the form of sound waves through the ear canal.

The eardrum and three small bones of the middle ear, like dominoes, transmit sound waves in sequence and amplify them step by step until they reach the inner ear and vibrate the lymphatic fluid of the cochlea.

In the cochlea, the nerves are connected into thousands of cilia, which are enough to convert the vibrations of sound into nerve electrical signals, and finally transmit the signals to the brain, and the person hears the sound.

In the whole process, any problem in any link may lead to deafness.

Genetic factors. Genetic defects, such as genetic or chromosomal abnormalities, can lead to hearing impairment, most often sensorineural hearing loss.

Maternal environmental influences during pregnancy.

It refers to the child's hearing impairment due to the influence of pathological factors such as maternal infection, poisoning or trauma during embryonic development, perinatal or delivery. For example, the mother's improper use of drugs during pregnancy, suffering from certain infectious diseases, improper use of forceps during childbirth, etc.

Infectious factors. Such as meningitis, measles and mumps and otitis media.

Tumor. Acoustic neuroma Patients may experience deafness due to tumor bleeding, edema of surrounding tissues, etc., which compresses the cochlear nerve.

Ototoxic drugs.

Certain medications can damage hearing, and there are currently more than 200 drugs and chemicals that have been documented to induce hearing***.

Trauma. Head injuries, especially skull fractures, put the ears at serious risk of hearing loss.

Abrupt changes in air pressure.

For example, diving, or when an airplane is taking off and landing, it may cause the inner ear fluid to move, and occasionally leakage or rupture, which can lead to damage to the inner ear nerve.

Deafness has different causes due to its different types. Conductive hearing loss** is mainly caused by inflammation, trauma, foreign body or other mechanical blockage, deformity. The main causes of sensorineural hearing loss are:

One is congenital deafness; Second, it is caused by the use of some drugs, such as some antibiotics, salicylic acid diuretics or antineoplastic drugs may cause neural hearing loss; Third, some viral infections, vascular lesions, and labyrinthine edema may also cause sensorineural hearing loss; Fourth, it is caused by some genetic or chromosomal abnormalities caused by heredity; fifth, it is caused by head trauma or ear trauma; Sixth, hearing loss caused by long-term noise; Seventh, it is caused by inner ear damage caused by systemic diseases, such as hypertension, arteriosclerosis, diabetes, chronic kidney disease, leukemia, hyperlipidemia, etc.; Eighth, it is caused by the lack of metabolic disorders of certain essential elements, such as iodine, iron, etc.; Nine is due to autoimmune inner ear disease.

The causes of deafness are hereditary, medicated, noise, neurological, and acquired, such as physical causes, traumatic causes, and otitis media.

There are many causes of deafness, which are mainly divided into congenital and acquired. There is a genetic factor among congenital factors, and deafness can be inherited. In addition, if the mother is infected during pregnancy and given ototoxic drugs, such as gentamicin, can cause fetal hearing problems, many of which can cause hearing loss at birth or shortly after birth, or it may be delayed.

There are many causes of acquired deafness, such as the greater the likelihood of hearing loss as we age. In addition, it has a lot to do with the surrounding environment, and working under long-term noise or long-term exposure to noise can also cause hearing loss.

Different types of deafness can be caused by different causes.

1. If it is conductive deafness, it may be caused by the following reasons:

1. Congenital developmental causes. It may lead to hypoplasia of the auricle, malformation of the ear canal, atresia of the ear canal, etc., which hinders the transmission of external sound waves to the inner ear.

2. Acquired factors. If the ear canal is covered with cerumen or if there is a pseudocholesteatoma, the ear canal may be blocked, preventing sound waves from entering the inner ear. In addition, if there is a perforation of the eardrum, a fracture of the ossicular chain, or a dislocation of the ossicular chain, the transmission of sound waves to the middle ear will be interrupted, resulting in conductive hearing loss.

2. If it is neural deafness, the patient may have a deafness gene in the family, and when the family member reaches a certain age, the disease may occur. In addition, certain ototoxic drugs, such as aminoglycoside antibiotics such as streptomycin, can also cause the development of neural hearing loss.

3. If it is mixed deafness, there are conductive deafness and neural deafness at the same time.