Evaluation of Oral Corticosteroid Therapy in Idiopathic Sudden Unilateral Hearing Loss.

Context: Idiopathic Sudden Sensorineural Hearing Loss (ISSHL) is a rapid-onset, sensorineural hearing loss of unknown etiology. It is one of the most common ENT emergencies, with spontaneous recovery occurring in 32% to 65% of cases. Treatment remains controversial, and the need for treatment itself is debated. Oral corticosteroids (OCS) are commonly used as first-line therapy, although they may have short-term side effects. Intratympanic corticosteroid injections (ITCIs) are an option for patients with contraindications to OCS or as a salvage treatment. The most recent Cochrane review includes three placebo-controlled studies on OCS efficacy (totaling 267 patients): two found no superiority of OCS, while one showed improvement in hearing. These studies are inconsistent and present methodological biases. Therefore, a sufficiently powered study is needed to assess OCS efficacy and establish clear treatment recommendations for ISSHL. Objectives: Primary Objective: To demonstrate the equivalence of OCS as first-line treatment for ISSHL compared to no treatment, in terms of hearing recovery between days 7 and 10. Secondary Objectives: To assess the effect of OCS versus no treatment on tinnitus, and hearing recovery based on initial severity of ISSHL. To evaluate hearing recovery in patients treated with rescue ITCIs. In the absence of equivalence, to investigate the superiority of OCS over no treatment. Methods: This multicenter, randomized, controlled equivalence trial will include two arms, each with 215 patients: one receiving OCS and the other a no-treatment control. In the absence of early hearing improvement, ITCIs will be administered regardless of study arm. Perspective: The goal is to clarify the role of OCS in treating ISSHL and guide the development of updated treatment recommendations.