Diagnostic criteria for idiopathic sudden sensorineural hearing loss (ISSNHL)^*.

*ISSNHL was defined according to criteria described by the Sudden Deafness Research Committee of the Japanese Ministry of Health and Welfare [23]. Patients were diagnosed with definite ISSNHL if they presented with all the listed symptoms, or with probable ISSNHL if they presented mainly with only symptoms 1 and 2. Diagnostic criteria for idiopathic sudden sensorineural hearing loss (ISSNHL)*.