Intracochlear Injection of Glucocorticoid

Inclusion Criteria: Age between 18 and 65 years Unilateral idiopathic sudden sensorineural hearing loss greater than 95dB at the average of 4 frequencies (500 Hz, 1000 Hz, 2000 Hz and 4000 Hz) in PTA (contralateral hearing is less than 30dB) at the onset of sudden hearing loss Participant who were treated with standard treatment for 14 days, but no recovery was confirmed as type IV (final hearing level with hearing gain of ≤15 dB) at the end of the 14-day treatment Exclusion Criteria: Bilateral sudden sensorineural hearing loss Hearing loss with known causes (e.g., Meniere's disease, retrocochlear pathology, history of otologic surgery, perilymphatic fistula, barotrauma) History in the past 6 months of ototoxic treatment such as chemotherapy, use of loop diuretics, high dose aspirin, etc History of sudden sensorineural hearing loss within the past 2 years History of ischemic diseases (cerebral infarction, myocardial infarction, peripheral arterial obstructive disease) Neuropsychiatric disorders (epilepsy, Parkinson's disease, Alzheimer's disease, multiple sclerosis) Severe hepatic or renal insufficiency The CT diagnosis is "abnormality of the round window niche"