Sudden deafness, also known as idiopathic blast deafness, is a sudden, unexplained sensorineural hearing loss that can reach a peak of deafness or even total deafness within 72 hours. It is a sensory-neural deafness caused by systemic or local factors. A small percentage of patients have dizziness.
Clinical manifestations
1. Deafness: sudden hearing loss of unknown cause (mostly unilateral), pure tone audiometry shows hearing loss of at least 20dBHL in at least two consecutive frequencies.
2. It may be accompanied by tinnitus (90% of cases), and may also have a feeling of stuffiness, fullness and obstruction in the ear (50% of cases).
3.It may be accompanied by vertigo, nausea, vomiting, etc. (30% of them have), or even auditory hypersensitivity and abnormal skin sensation around the auricle (common in total deafness type); secondary symptoms include: fear, anxiety, etc.
[Causes of onset].
Most of the patients have no obvious reason for the onset of the disease, and many of them occur during sleep and feel tinnitus and deafness when they wake up. Some patients have a history of exertion, emotional stress, nervousness and cold, which may have some relationship with the onset of the disease. etc.
Typing]
Domestic classification: low-frequency descending type, high-frequency descending type, flat descending type, total deafness four types
Differential diagnosis
What needs to be clarified must be: firstly, life-threatening diseases should be excluded, such as: intracranial malignant tumor, stroke, auditory neuroma, nasopharyngeal carcinoma, etc. Secondly, we need to exclude otitis media, Meniere’s disease, etc. For bilateral onset, we need to consider immune diseases, hereditary diseases, intracranial diseases, hematologic diseases, poisoning, noise, etc.
The examination that must be performed]
1.Otoscopy.
2. Audiological examination (tuning fork, pure tone audiometry, acoustic conduction resistance).
3. Vestibular function examination for patients with vertigo.
Additional examinations may be required
1.Hearing mechanics: otoacoustic emission, ABR, cochlear electrogram, etc.
2.Imaging: MRI to exclude auditory neuroma and intracranial lesions, and CT of temporal bone to exclude middle ear lesions.
3. laboratory tests: e.g. C-reactive protein, routine blood, fibrinogen, lipids, etc.
4. Serological tests: mycoplasma, syphilis, herpes virus, HIV, etc.
【Treatment】
Low-frequency descending type has the best effect and high self-healing rate, flat descending type is second, high-frequency descending type, total deafness type has a low cure rate and should be actively treated.
Low-frequency descending type treatment principle: this type may be fluid in the inner ear, so it should be salt and water restriction, preferably without saline, minor can be oral drugs, serious can be infusion, such as: Jinadu plus hormone, medicine available hyperbaric oxygen, a few patients ineffective can add fibrin-lowering drugs, such as bacitracin.
High-frequency descending type treatment principles
1, improve microcirculation, drugs or other methods (such as hyperbaric oxygen, physical therapy, etc.), plus hormones.
2.Ion channel blockers (such as lidocaine).
3.Nutritional nerve drugs.
Full-frequency descending type (including flat type and total deafness)
1.Drugs that lower fibronectin.
2.Hormone.
3.Improve microcirculation.
Prognosis]
The prognosis of low-frequency descending type is good, up to more than 70%, while the prognosis of high-frequency descending type and total deafness type, reports show only less than 20%. The more severe the hearing loss, the worse the prognosis, and the earlier the treatment, the better.