Ménière’s disease is an idiopathic inner ear disorder, once called Meniere’s disease, first described in 1861 by the French physician Prosper Ménière. The main pathological change of the disease is the accumulation of water in the membranous vagus, which is clinically manifested by recurrent episodes of rotational vertigo, fluctuating hearing loss, tinnitus, and a feeling of stuffiness in the ear. The disease occurs mostly in middle-aged and young adults between 30 and 50 years of age, and is rare in children. There is no significant difference in the incidence between men and women. Binaural disease accounts for 10% to 50% of the cases.
I. Etiology
The etiology of Meniere’s disease is still unclear, but in 1938 Hallpike and Cairns reported that the main pathological change of the disease was fluid in the membranous vagus, and this finding has been confirmed by many scholars. However, how membranous vagal effusion arises is difficult to explain clearly. The known causes include the following factors: various infectious factors (bacterial, viral, etc.), injuries (including mechanical or acoustic injuries), otosclerosis, syphilis, genetic factors, allergies, tumors, leukemia, and autoimmune diseases.
DeSousa (2002) referred to vestibular symptomatic disorders produced by known causes of membranous vagal effusion as Meniere’s syndrome, while Meniere’s disease is considered to be an idiopathic membranous vagal effusion.
II. Clinical manifestations
Typical Ménière’s disease has the following four symptoms: vertigo, deafness, tinnitus and a feeling of stuffiness in the ear.
1.Vertigo
It is mostly sudden onset of rotational vertigo. Patients often feel that the surrounding objects rotate around them in a certain direction, and the symptoms can be reduced when the eyes are closed. It is often accompanied by autonomic reflex symptoms such as nausea, vomiting, pale face, cold sweat and drop in blood pressure. Any movement of the head can make the vertigo worse. Patients are always conscious, and individual patients remain awake even if they suddenly fall down.
The duration of vertigo is mostly several 10 minutes or several hours, and the longest duration is not more than 24 hours. The length of the interval varies from one person to another, ranging from a few days to several years. The duration and severity of each attack varies from patient to patient and from patient to patient. The more frequent the attacks of vertigo, the longer the duration of each attack and the shorter the interval.
2.Deafness
In the early stage, it is mostly sensorineural deafness with low frequency (125-500Hz) drop, which can be fluctuating, with hearing loss in the attack period and partial or complete recovery in the interval. As the disease progresses, the hearing loss can gradually worsen and high frequency (2 to 8 kHz) hearing loss gradually occurs. The disease may also present a special phenomenon of hearing change: the phenomenon of double hearing, that is, the affected ear and the healthy ear can hear the same pure tone as two different tones and timbre of sound. This phenomenon can also occur when the affected ear and the healthy ear hear the same pure sound with two different tones and timbres.
3. Tinnitus
Tinnitus may be the earliest symptom of the disease. At the initial stage, it may appear as a persistent low-pitched blowing wind-like sound, and at the later stage, it may appear as a cacophony of various tones, such as ringing, cicada sound, wind blowing sound, etc. Tinnitus may appear suddenly or worsen before the onset of vertigo. The tinnitus disappears in intervals, but it may persist in patients with long-standing disease. A small number of patients may have bilateral tinnitus.
4.Ear stuffiness and swelling
During the period of vertigo attack, the affected ear may feel fullness, pressure and heaviness in the ear. A few patients complain of mild pain in the affected ear and itching in the ear.
III. Examination
1. Audiological examination
(1) Pure tone audiometry can understand whether the hearing is declining, the degree and nature of hearing loss. In the early stage, it is mostly low-frequency sensorineural deafness, and the hearing curve is mildly ascending. After multiple episodes, high frequency hearing loss, the hearing curve may be flat or decreasing. Pure tone audiometry also allows dynamic observation of continuous changes in the patient’s hearing.
(2) Cochlear electrocochleography This test provides an objective understanding of the presence of fluid in the membrane vagus. -An SP/AP amplitude ratio >0.37 is diagnostic and can indirectly indicate the presence of fluid in the membranous vagus.
(3) Otoacoustic emissions can first reflect the functional status of the cochlea in patients with early Ménière’s disease. When pure tone audiometry does not reveal abnormalities in the early stage of the disease, transient otoacoustic emissions can be reduced or not induced.
2. Nystagmography
At the climax of the attack, spontaneous nystagmus can be seen. Horizontal spontaneous nystagmus and positional nystagmus with different rhythms and intensities, initially to the affected side and then to the healthy side, can be observed or recorded by nystagmography, and the nystagmus shifts to the healthy side during the recovery period. The intermittent spontaneous nystagmus and the results of various evoked tests may be normal.
3.Glycerol test
It is mainly used to determine whether there is membrane vagal fluid accumulation. Because glycerol has high osmotic pressure and the molecular diameter is smaller than the diameter of the small pores of the cytoplasmic plasma membrane, it can diffuse to the cells at the edge of the inner ear, increasing the intracellular osmotic pressure and causing the water in the endolymphatic fluid to enter the blood vessels of the vascular striae via the cellular pathway to achieve the effect of decompression.
4. Vestibular function test
(1) Hot and cold test early vestibular function on the affected side can be normal or mildly diminished, after several episodes there can be a dominant bias on the healthy side, and in the late stage there is light paralysis of the semicircular canal or loss of function.
(2) Vestibular evoked myogenic potentials may show amplitude and threshold abnormalities.
(3) Hennebert’s sign stapedial pedicle may induce vertigo and nystagmus when adhering to the distended balloon and increasing or decreasing the air pressure in the external auditory canal. Henenbert’s sign may appear positive in patients with Meniere’s disease.
5.Imaging examination
CT examination of the temporal bone can show narrowing of the vestibular canal. MRI of the endolymphatic vagus under special contrast may show thinning of the endolymphatic vessels in some patients.
6.Immunological examination
Some patients have HSP70 antibody and 68kD antigen antibody.
IV. Diagnosis
The exact diagnosis of Ménière’s disease is almost impossible due to the inability to perform pathological examination of biopsied inner ear tissue. At present, the diagnosis of Ménière’s disease is mainly based on medical history, comprehensive examination and careful differential diagnosis, and the clinical diagnosis can be made after excluding other diseases that may cause vertigo.
V. Differential diagnosis
Before confirming the diagnosis of Ménière’s disease, various diseases causing vertigo should be excluded, such as central system diseases, vestibular system diseases, other system diseases, etc.
1.Central diseases
Hearing neuroma, multiple sclerosis, aneurysm, cerebellar or brainstem tumor, cervical vertigo, Amolk-Chiat malformation, transient episodic cerebral ischemia, cerebrovascular accident, cerebrovascular insufficiency of blood supply, etc. Especially in acute episodes of vertigo, acute neurological diseases such as dorsolateral medullary syndrome, posterior circulation ischemia, cerebrovascular lesions, etc. should be excluded first.
2. Peripheral diseases
Benign paroxysmal positional vertigo, vestibular neuritis, vestibular drug intoxication, vaginitis, sudden deafness, Hunt syndrome, otosclerosis, autoimmune inner ear disease, ectolymphatic fistula, etc.
3.Metabolic diseases
Diabetes mellitus, hyper- or hypothyroidism, Cogan syndrome, blood disorders, autoimmune diseases, etc.
4.Other systemic diseases
Such as heart disease, primary hypertension, etc.
VI. Treatment
Since the cause and pathogenesis of Ménière’s disease are unknown, there is no treatment method to cure the disease. At present, most of the medications and surgeries are used to regulate the autonomic nerve function, improve the microcirculation in the inner ear, and release the water in the vagus.
1.Drug treatment
(1) Vestibular nerve inhibitors are mostly used in the acute attack period, which can weaken the activity of vestibular nerve nucleus and control vertigo. The commonly used ones are diazepam, diphenhydramine, diphenhydramine, etc.
(2) Anticholinergic drugs such as scopolamine and scopolamine can relieve nausea and vomiting.
(3) Vasodilators can change the metabolism of ischemic cells, selectively diastolic ischemic area blood vessels, relieve local ischemia. Commonly used are flunarizine (Cipro), betahistine, ginkgo biloba, etc.
(4) Diuretic and dehydrating drugs can change the fluid balance in the inner ear, reduce endolymph and control vertigo. Commonly used are dihydrocoumaric acid, acetazolamide, etc.
(5) Glucocorticoids can be used to treat dexamethasone, prednisone, etc. based on the immune response theory.
(6) Vitamins, such as vitamin B1, B12, vitamin C, etc., can be used for the treatment of metabolic disorders and vitamin deficiency.
2.Medium ear pressure treatment
In 2001, Densert in Sweden reported the application of portable middle ear pressurizer (Meniett device) to treat Meniere’s disease, which can control the vertigo symptoms of patients in short or long term.
3.Chemical vagotomy
It refers to the use of ototoxicity of aminoglycoside antibiotics to destroy the vestibular function of the inner ear for the purpose of treating vertigo. The main drugs used are streptomycin and gentamicin. The drugs can be administered systemically and in the tympanic chamber.
(1) Systemic administration according to Langman (1990), systemic intravenous injection of streptomycin can treat bilateral Ménière’s disease and relieve vertigo symptoms.
(2) Intra tympanic injection uses the principle of semi-permeability of the round window membrane, and the drug injected in the tympanic chamber can enter the inner ear for therapeutic purpose by permeation. At present, intra-drum injection of gentamicin has become a common method and has achieved good clinical results, the main complication of which is hearing loss.
4.Surgical treatment
Surgical treatment can be considered after the failure of drug therapy for Meniere’s disease. There are many kinds of surgeries, such as endolymphatic sac surgery (endolymphatic sac decompression, endolymphatic sac shunt); stellate ganglion closure; vagotomy and vestibular nerve dissection for those who lose the ability to work and live due to vertigo and those who lose the hearing of children.
The choice of surgery should be based on the severity of hearing, vertigo and other symptoms, as well as the patient’s age, occupation and lifestyle. For example, young people and patients who need to be employed will benefit more from choosing surgery than retired elderly people. In contrast, vestibular disruption can occur after surgery, making it unsuitable for patients who work at heights.
Depending on whether vestibular function and hearing are preserved, the surgery can be classified as conservative endolymphatic sac surgery, partially destructive surgery, and destructive.