RESUMO
Over 60 years since its first report, sudden sensorineural hearing loss (SSNHL) still represents an ill-explained condition, with potentially devastating effects for the quality of life of previously well patients. The present study critically reviewed the available evidence regarding the efficacy of intra-tympanic steroid administration in the treatment of SSNHL. Factors affecting that efficacy were also explored. The literature was systematically reviewed in Medline and other database sources until July 2011, and analyzed through critical analysis of pooled data. The study selection included multi-center prospective randomized control trials, prospective randomized comparative, prospective comparative and prospective studies, retrospective comparative and retrospective studies. The total number of analyzed studies was 43. Intra-tympanic steroids appear to be effective as primary (strength of recommendation A), or salvage treatment (strength of recommendation B) in SSNHL. It is difficult to draw definite conclusions regarding the efficacy of combination therapy. The identification of a time window for effective treatment in the former two approaches yields a grade C strength of recommendation. Primary intra-tympanic treatment is the most effective modality in terms of complete hearing recovery (34.4% cure rate). There is not enough evidence to attribute treatment failures to impaired permeability of the round window membrane. Most complications of intra-tympanic treatment are minor, temporary, and conservatively managed. Intra-tympanic steroids can theoretically provide a more organ-specific treatment in patients with SSNHL. The observation that they seem effective both as primary and salvage treatment modalities with a very low complication rate may have serious implications for current clinical practice.