Replay

Introduction Meniere's syndrome deaf patients generally have a resilience to hyperacoustic allergy, and some can listen to pure sound as two different tones of sound or tone, that is, the phenomenon of Diplacusis. A lot of evidence indicates that the autonomic nervous system disorder causes the inner ear vasospasm, causing the blood flow of blood vessels to decrease, the secretion of endolymph fluid is reduced, the intermediate metabolites are aggregated, the osmotic pressure in the cochlear tube is increased, the lymphatic space and the intravascular fluid are inward lymph. Infiltrate to form a effusion. The decrease in blood pressure response to endogenous or exogenous norepinephrine in Meniere patients may be caused by an obstructive effector of alpha adrenaline. Cervical spondylosis affects the vertebral artery system circulation and can also induce the disease. Excitement and overwork can often be used as predisposing factors.

Cause

The cause is multifaceted and generally considered to have the following factors:

Inner ear blood circulation disorder

A lot of evidence indicates that the autonomic nervous system disorder causes the inner ear vasospasm, causing the blood flow of blood vessels to decrease, the secretion of endolymph fluid is reduced, the intermediate metabolites are aggregated, the osmotic pressure in the cochlear tube is increased, the lymphatic space and the intravascular fluid are inward lymph. Infiltrate to form a effusion. The decrease in blood pressure response to endogenous or exogenous norepinephrine in Meniere patients may be caused by an obstructive effector of alpha adrenaline. Cervical spondylosis affects the vertebral artery system circulation and can also induce the disease. Excitement and overwork can often be used as predisposing factors.

2. Congenital dysplasia

Congenital anatomical abnormalities such as dysplasia of the ear, sigmoid sinus advancement, occlusion of the cochlear aqueduct, narrow or occlusion of the endolymphatic duct, minimal or absent development of the endolymphatic sac, or development of any of the elliptical sac or membrane labyrinth or This disease can occur with atresia.

3. Endocrine disorders and metabolic abnormalities

Iwata (1958) first proposed that the disease is a syndrome caused by endocrine disorders between the pituitary gland and the adrenal gland. Alcohol and lipid-like metabolism disorders, increased plasma osmotic pressure, electrolyte and egg blood components, mainly in the blood and lymph potassium imbalance. Therefore, blood consistency, high blood lipids and low fibrin, etc., can induce this disease. In addition, the adrenal cortex hypofunction, hypothyroidism, can cause dysfunction of the autonomic nervous system, thereby causing blood circulation disorders in the inner ear, which can produce lost water.

4. Traumatic brain injury

Trauma caused by fracture of the tibia and fibula of the inner ear, causing blockage of the cochlear duct or vestibular duct, and obstruction of the endolymphatic circulation, resulting in stagnant water.

5. Inner ear immune response

Quinke (1893) has suggested that the disease is associated with angioedema. Duke (1923) proposed that this disease is directly related to type I allergic reactions. Food allergens such as wheat, beef, milk, and eggs are more common, while inhalation allergens such as pollen and dust are less. Ingestion of allergic foods or intradermal injections of allergic food extracts can occur, and the symptoms of certain allergic foods can be alleviated. According to Punec, 162 cases of Meniere's disease accounted for 14% of type I allergies. According to animal experiments, Park Erjiro was sensitized with chicken serum and tuberculin in the stem of the stem, and it was found that humoral immune-mediated type III allergic reaction (antibody antigen reaction) can cause vestibular membrane permeability, vascular pattern Increased secretion, resulting in endolymphatic water. The fact that antibodies are locally produced in the inner ear has been accepted by the clinical community. According to the study, the autoantigen may be type II collagen of the inner eardrum tissue blood vessels, the inner ear matrix structure, the endolymphatic sac and the avascular region of the inner ear. According to Hughes (1983), autoimmune-induced Meniere's disease accounts for about 10%, while Shea (1982) reports an estimated 50%.

6. Other

Bacterial toxins and viral infections or syphilis in chronic tonsillitis, nasal sinusitis, appendicitis and cholecystitis may lead to increased permeability of the wall through poisoning, injury and immune reaction, causing lost water.

In summary, the labyrinthine neurovascular dysfunction is the basis of the onset of this disease. The reasons are various. The pathogenesis has not been thoroughly investigated, and further research is needed in the future.

an examination

Related inspection

Pure tone audiometer examination hearing test vestibular function test hearing test method otolaryngology CT examination

During the attack period, there may be spontaneous horizontal nasal congestion and horizontal rotation, which is especially fast to the affected side, especially when the eyes are closed. At the end of the episode, the direction of the nystagmus turned to the healthy side, showing a paralytic nystagmus, which gradually disappeared. It is difficult to carry out item-by-item examinations during episodes, and the following tests are often performed during the interim period:

First, the auditory function

Shown as a typical cochlear lesion.

1, pure tone audiometry

In the early stage, the low-frequency sensorineural deafness was flat, and the episode was aggravated. The episode was aggravated. After the attack, it could partially or completely recover from the volatility hearing curve. In the late stage, it showed a steady decline curve. The hearing loss was 5~10 years after the onset. 70dB.

2, language audiometry

The language hearing threshold and the pure tone hearing threshold have a good correlation. Due to the sound distortion, the language discrimination rate can be reduced to 40% to 70%. According to Stahle's (1976) follow-up of 356 patients, the general language acceptance threshold was 62 dB, the resolution was 52%, and the pure tone loss averaged 55 dB.

3, threshold function check

The binaural alternating loudness balance test (ABLB) was positive. The sound intensity difference threshold (DLI) is lower than 0, 6dB, and the short incremental sensitivity index (SISI) is increased by more than 80%, suggesting that there is auditory re-vibration.

4, impedance audiometry

Tympanic force type A, no sound decay and acoustic reflection attenuation, the difference between the tibial muscle reflex threshold and the hearing threshold is below 60dB, which is called Metz positive, which also indicates re-vibration.

5, Bekesy self-testing

It is a type II curve.

6, cochlear electrogram

The SP/AP amplitude ratio is >37%, and Gibson reports that the SP-AP aspect ratio increase is more meaningful than the amplitude ratio increase.

Second, the vestibular function check

Early vestibular function can be normal, and its function gradually declines with frequent episodes, and can be completely lost in the advanced stage.

1, Hallpike hot and cold temperature test

This method is most commonly used, about one-third of patients responded normally, 1/3 responded weakly, and another 1/3 lost completely. Cawthorne et al performed 900 cases of hot and cold temperature change, 640 cases of sputum sputum, 75 cases of dominant bias, 108 cases of the combination of the two, and 26 cases of unknown records. It can be seen that tube paralysis and dominant bias are the most. The vestibular dysfunction is most severe in the first 5 years of illness and is consistent with cochlear dysfunction. Sometimes in order to simplify the examination in the clinic, qualitative results can be obtained by flushing the tympanic membrane to the upper quadrant with 2 ml of ice water.

2, nystagmus electrogram examination

Most of the nystagmus is horizontal, the severe one is horizontal rotation type, the acute phase is to the opposite side, and then turns to the same side, called recovery nystagmus. Myerhoff (1981) performed an ENG examination of 211 patients and found that 21% of responders were normal, 65% were sputum, and 14% were dominant. Those with normal reactions cannot rule out the existence of this disease. The saccade, visual tracking test and visual inspection were normal, and the rotation test and DC stimulation test were performed, and the function was weakened or normal. Recently, sinusoidal harmonic acceleration (SHA) vestibular function check has been used. The stimulus can be repeated and controlled. Phase gain, phase delay and dominant bias can be obtained. The phase delay is the most sensitive, the phase delay is the most sensitive, and the phase gain is the most. Joint application is ideal.

3, other

There was no abnormality in the nervous system examination. The eardrum is normal. X-ray of the humeral tomography, according to Cole (1972) reported in 250 cases, 25 cases (10%) showed bilateral sclerotic lesions on both sides. At the same time, the internal auditory canal enlargement of the acoustic neuroma can also be excluded.

Differential diagnosis

Disease identification

Fu Cong phenomenon: The degree of hearing loss is reduced or disappeared due to the increased sound intensity of the stimulus; the strong sound tolerance is reduced, and the patient feels ear pain when the normal human's strong sound tolerance (105-110 dB) is not reached.

The material in this site is intended to be of general informational use and is not intended to constitute medical advice, probable diagnosis, or recommended treatments.