Idiopathic sudden sensorineural hearing loss is not an otologic emergency

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

Prospective study.

Otorhinolaryngologic emergency center in Paris, France.

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.

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.

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.

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.

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.