Idiopathic sudden sensorineural hearing loss is not an otologic emergency.

Objective: To investigate whether delay in treatment has any influence on the audiometric outcome at Day 30 in idiopathic sudden sensorineural hearing loss.

Methods: Prospective study. Methods: Otorhinolaryngologic emergency center in Paris, France. Methods: Three hundred forty-seven consecutive cases of sudden sensorineural hearing loss were examined. A neurologic or retrocochlear cause was revealed in 17 cases. Four additional cases were lost for follow-up. Three hundred twenty-six cases of "idiopathic" sensorineural hearing loss seen within 7 days of onset were enrolled and classified by type according to five audiogram shapes: low tone (Type A), flat (Type B), high tone (Type C), cup-shaped (Type D) or total or subtotal (Type E). Because of loss for follow-up, the hearing outcome at 1 month could be evaluated in only 249 cases. Methods: All 326 patients were given 1 mg/kg per day corticosteroids intravenously for 6 days and 500 ml mannitol 10% in the subgroup presenting ascending audiometric shape. Methods: The following parameters were used. The first parameter was hearing recovery (initial PTA-PTA at Day 6 or Day 30). It was considered as complete if final PTA was below 25 dB. The second parameter was incidence of hearing recovery based on the following formula: (initial PTA-PTA on a given test day)/(initial PTA) x 100%. Using regression analysis and ANOVA, the audiometric outcome was analyzed at Day 6 and Day 30 as a function of the day of onset of treatment and of the audiometric type.

Results: Whatever the audiometric type, there was no significant difference in final outcome whether the treatment was started within the first 24 hours or within the first week.

Conclusions: Delay in initiating treatment does not appear to influence the final degree of hearing loss. Idiopathic sudden sensorineural hearing loss cannot be considered as an otologic emergency.