Sudden sensorineural hearing loss treated with intratympanic dexamethasone injection

Objective To evaluate the effect of different protocols of intratympanic dexamethasone injection in patients with unilateral sudden sensorineural hearing loss (SSNHL) who have failed to respond to typical medical treatment (including systemic steroid treatment). Methods From January 2005 to January 2008, 71 patients who were diagnosed with unilateral SSNHL and failed typical medical treatment received intratympanic dexamethasone injection. Four injection protocols were employed: injection of 0.3 ml dexamethasone(5 mg / ml) three times a week for 3 weeks for a total dose of 13.5 mg (Group I, n=16); injection of 0.6 ml (5 mg / ml) dexamethasone three times a week for 3 weeks for a total dose of 27 mg (Group II, n=18); injection at 0.3 ml(5 mg/ml) week for 6 weeks for a total dose of 9 mg (Group III, n=18); injection at 0.3 ml (5 mg / ml) / 2 days for a total dose of 4.5 mg (Group IV n=19). Hearing recovery was assessed by pure tone audiogram. Results The total effective rate was 37.5%, 38.89%, 33.33% and 36.84% for each treatment protocol, respectively, with no statistical difference between them (P > 0.05). The results suggest that a total dose of 4.5 mg (injected once a week for 3 weeks) is the most adequate protocol, and increasing dose or injection frequency yields no additional benefits. Conclusion Intratympanic dexamethasone significantly improves the prognosis of SSNHL. Small dose at low injection frequency is sufficient. Further multicenter studies are needed to determine the standard treatment protocol.