Sudden deafness is a sudden, unexplained sensorineural hearing loss that occurs within minutes, hours, or 3 days, with a hearing loss of at least 20 dB in at least 2 connected frequencies. Accompanying symptoms: In addition to hearing loss, it is often accompanied by tinnitus, vertigo, and a feeling of fullness in the ear. The onset is mostly unilateral, with only 5% being bilateral. About 80% of patients with sudden deafness have tinnitus and dullness, and 30% have vertigo, suggesting that these patients also have peripheral vestibular dysfunction. Morbidity: The annual incidence of sudden deafness is around 5-30/100,000 and can occur at all ages, with the average age of onset being 50-60 years. The average age of onset is 50-60 years. Men and women have an equal chance of developing the disease. The degree of hearing loss can be mild, moderate, severe, or profound, and can involve low, mid, and high frequencies. Audiological examination: Pure tone audiometry and acoustic conductance examination are used to determine the degree of hearing loss, the type of hearing curve, and the basic condition of the middle ear. Otoacoustic emissions, speech audiometry, high stimulation rate ABR, and cochlear electrograms are also important in the diagnosis of sudden deafness. Vestibular function tests then evaluate the patient for concomitant vertigo. Imaging: Cranial or endocranial magnetic resonance imaging (MRI) can help rule out postcochlear lesions such as tumors, cerebrovascular disease, and demyelinating lesions as causes of sudden hearing loss, and cranial arteriography (MRA) and cranial venography (MRV) can help to understand the cochlear blood supply for targeted treatment. The main treatment methods include hormonal drugs, drugs to improve inner ear circulation, neurotrophic drugs, anticoagulant drugs, and at the same time, according to the type of hearing loss, we can choose hyperbaric oxygen and other auxiliary treatment methods. Factors affecting the efficacy: The more timely the treatment, the more effective it is. The degree of hearing recovery is related to the degree of loss, accompanying symptoms and the presence of systemic diseases. Children tend to have more difficulty recovering than adults.