III. Sudden deafness
1. What is sudden deafness?
Sudden deafness is a sudden onset of sensorineural deafness of unknown cause, also known as tyrannical deafness in Chinese medicine, first described by De Klevn (1944). The incidence in both ears accounts for 4%. There is no significant difference in the incidence between the sexes and the left and right sides. The incidence increases with age, and 3/4 of the patients are 40 years old or older at the time of the disease. The effect of treatment is directly related to the time of consultation, which is an otologic emergency.
2. What is the cause of sudden deafness?
The etiology of sudden deafness is still unclear, and there are many hypotheses about its pathogenesis, such as viral infection theory, inner ear blood supply disorder theory, autoimmune theory and membrane vagus rupture theory, etc. Various triggering factors also play an important role in the development of sudden deafness. The common triggering factors include cold, fatigue, mood swings, etc.
3.What are the clinical characteristics of sudden deafness?
(1) Deafness
This disease is aggressive and hearing loss can occur in an instant, within hours or days, or sudden deafness can be felt in the morning. In chronic cases, the deafness may gradually increase and stop progressing only after a few days. Its degree ranges from mild to total deafness. It can be temporary or permanent. It is mostly unilateral, but occasionally occurs bilaterally or sequentially. It may be cochlear deafness or postcochlear deafness.
(2) Tinnitus and deafness
Tinnitus occurs before and after deafness, accounting for about 70% of cases. It usually appears a few hours before deafness and is mostly a buzzing sound that can last for a month or more. Some patients may emphasize the tinnitus and ignore the hearing loss.
(3) Vertigo
About half of sudden deafness is associated with varying degrees of vertigo, about 10% of which are severe deafness with nausea and vomiting that can last 4 to 7 days, and mild dizziness that can be present for more than 6 weeks. A small number of patients present with vertigo as the main symptom and are easily misdiagnosed as Meniere’s disease. The vertigo attacks are associated with impairment of vestibular function on one or both sides and can gradually recover.
4.Why is sudden deafness accompanied by vertigo?
According to the theory of inner ear blood supply disorder, the blood vessels of inner ear blood supply are peripheral vessels and their anastomotic branches are few, which increases the vulnerability of inner ear blood supply system, and the regulation of these vessels is influenced by cervical ganglion and sympathetic postganglionic fibers in addition to vegetative nerve and local regulation mechanisms, thus the peripheral vessels of inner ear are prone to thrombosis or embolism, vasospasm, decreased blood flow, cochlear blood As a result, blood flow decreases and cochlear blood perfusion decreases, causing ischemia and hypoxia in the inner ear, resulting in necrosis and degenerative changes in the hair cells of the inner ear, and when the lesion involves the vestibule, vertigo symptoms will occur.
5.What is the diagnosis of sudden deafness based on?
(1) Medical history
Patients with sudden deafness due to viral infection may clearly provide a history of influenza, upper respiratory tract infection, sinusitis, etc., or contact with a virally infected person, which can occur weeks before the hearing loss. Patients with sudden deafness due to vascular pathology may provide a history of heart disease or hypertension, or they may have a history of diabetes mellitus, atherosclerosis, hypercholesterolemia, or other systemic diseases affecting the microvascular system. Patients with ruptured labyrinth membranes tend to have a clear history of exertion or experience of altered air pressure, such as difficult urination, defecation, coughing, sneezing, bending, laughing, etc. or swimming, diving, diving with a ventilator or underwater breathing apparatus, or unusual flight activities.
(2) Systemic examination
The cardiovascular system, coagulation system, metabolism and immune reactivity of the body should be targeted. Neurological examination should exclude endo-aural tract and cerebellar pontocerebellar horn lesions, vertebrobasilar and cerebral vascular circulation disorders, such as taking endo-aural tract films and cervical spine films, cranial CT scan, fundus and cerebral hemogram.
(3) Laboratory tests
Including routine blood, blood biochemistry, coagulation, easy embolism examination.
(4) Otoscopic examination
The tympanic membrane is often normal or may be slightly red.
(5) Hearing examination
Pure tone audiometry with increased air bone conduction threshold.
(6) Vestibular function examination
It should include functional examination of the optic oculomotor system (gaze oculomotor response, sweep test, smooth tracking test, optic oculomotor nystagmus), hot and cold test, and positional nystagmus test.
6. What are the treatment options and principles for sudden deafness?
Treatment plan for sudden deafness: active vasodilation with hypofibrinogen therapy to improve inner ear microcirculation, as well as nutritional nerve and hormone therapy, commonly used drugs are prostil and bactrim, nutritional nerve application vitamin B1, adenosine cobalamin, hormone is dexamethasone, etc.
Treatment principle of sudden deafness: treatment with drugs to improve microcirculation or nerve nutrition within 7 days of the attack can be effective. Therefore, once sudden deafness occurs, it should be treated urgently.
(1) General treatment
Patients should be hospitalized and put on bed rest if possible.
(2) Nerve-nourishing drugs
Vitamin B1, vitamin B12, glutamate and energy synergists (ATP, coenzyme A, cytochrome C) should be used.
(3) Vasodilators
They are mainly used for sudden deafness caused by vascular lesions. Commonly used drugs include prostaglandin, Chinese medicine preparation Chuanxiongzin, asparagine, ginkgo biloba preparation (Jinaduo), etc.
For patients with hypercoagulable tendency of blood, bacitracin, fibrin-lowering and microcirculation-improving treatment can be standardized. Patients with hypertension, diabetes mellitus, hyperlipidemia, actively treat the primary disease.
(4) Other treatment methods: such as hyperbaric oxygen therapy, microwave physiotherapy, etc.
Hyperbaric oxygen can improve the oxygen supply to inner ear cells and promote the functional recovery of focal tissue cells; microwave therapy has the effect of improving inner ear microcirculation and reducing the inflammatory response.
7.What is the prognosis of sudden deafness?
The prognosis of sudden deafness is related to the degree of hearing loss, the duration of the disease and whether it is accompanied by vertigo or not, if it is accompanied by The prognosis is related to the degree of hearing loss, the duration of the disease and the presence of vertigo.
8.How to prevent and regulate sudden deafness?
(1) Patients with sudden deafness should rest at home, especially avoiding exposure to noise or excessive sound. Don’t answer the phone or listen to music with headphones for a long time. Keeping the home environment tidy and the patient in a comfortable mood is conducive to recovery.
(2) Prevent colds. Some patients with sudden deafness may be indirectly related to colds, so preventing colds can reduce the onset factors.
(3) Don’t overexert yourself, and make sure that you have a regular diet. Since this disease mostly occurs in middle-aged people, middle-aged people should pay more attention to this point.
(4) Emotional stability, avoid anger and ecstasy, because these can cause the imbalance of neurohumoral regulation in the body, resulting in impaired blood circulation in the ear and deafness.