hearing loss
Introduction
Introduction Normal hearing refers to a category of auditory sensitivity, which is the average of the normal ear hearing measurements of healthy young people, not an absolute value. Hearing impairment occurs when a sound or sensory portion of the auditory system is damaged or functionally impaired, commonly referred to as hearing loss. The degree of hearing loss is light and heavy, light is heavy, and heavy is sputum. Generally speaking, deaf people mean that practical hearing is almost completely lost. Children have lost their hearing since childhood, and their chances of learning a language are hoarse.
Cause
Cause
(1) Sounding
Lesions in the outer ear, middle ear, and a few volutes can also be expressed as sound sputum.
(2) Sensorineural hearing loss
It is impossible or difficult to feel the sound of the lesions in the cochlea and the posterior cochlea. According to the difference of the anatomy of the lesion, it can be divided into four categories.
1. Cochlear sputum: Hair cell lesions caused by various reasons such as ototoxic drug poisoning, so that the stimulation of sound waves can not produce normal electrical activity.
2. Neurological spasm: Due to cochlear neuropathy, the electrical activity of hair cells cannot cause the nerves to be excited or unable to be uploaded to the brainstem.
3. Brain stem sputum: The brain stem lesions prevent the impulse of the cochlear nerve from being uploaded to the cortical center.
4. Cortical sputum: The ability of the lesion to impede the transmission of information and the ability to conduct comprehensive analysis. The auditory system on each side is treated by the cortical centers on both sides. Therefore, the cortical tendons must have both sides of the central artery and can cause paralysis.
Examine
an examination
Related inspection
Voice test, auditory nerve, catheterization, tracheal ultrasound, Weber test
For every deaf patient, the cause of deafness should be found as much as possible. A detailed medical history is extremely important for the diagnosis of deafness.
(1) Deafness is congenital or acquired
Congenital people are often undeveloped or stunted with spirals and related structures. Acquired is associated with degeneration of the inner ear receptor.
(2) Whether there are genetic factors
About half of the severe deafness in children is hereditary.
(3) Whether the deafness is accompanied by abnormalities in other parts
Those with other organ abnormalities are more related to congenital or genetic factors.
Diagnosis
Differential diagnosis
It should be differentiated from the following symptoms:
1. Hearing impairment: Hearing impairment refers to a structural defect of the auditory organ due to congenital or acquired causes, or a partial or total disorder of the function, which may result in difficulty in listening or recognizing the sound.
2. Hearing loss: The outside voice is transmitted to the inner ear of the person through two channels. One is the air conduction pathway through the external auditory canal, the tympanic membrane, the ossicular chain, and the vestibular window. The other is the movement of the skull and the compression of the bone. When the sound is transmitted to the inner ear, the shearing motion of the hair cells on the basement membrane of the cochlea produces action potentials, and any pathological changes occur, which can affect hearing.
