Intratympanic dexamethasone perfusion versus injection for treatment of refractory sudden sensorineural hearing loss

Intratympanic steroid treatment for the sudden sensorineural hearing loss (SSNHL) has a long history and many techniques have been developed. The efficacies are varied in different studies owing to different criteria, steroid type and dose, delivery methods, or absence of comparison groups. Recently, animal experiments suggested that continuous delivery systems produce the higher inner ear drug concentrations than other ways. This study was aimed at evaluating the efficacies of intratympanic dexamethasone perfusion versus injection for treatment of refractory sudden sensorineural hearing loss (RSSNHL). A total of 136 patients were enrolled in this nonrandomized, prospective, controlled study. Thirty-two patients were treated with continuous intratympanic dexamethasone perfusion via round window microcatheter by an electronic pump at a rate of 10 mu l/min twice daily for 7 days and 34 patients underwent intratympanic dexamethasone injection of the same dosage. Seventy patients who refused to undertake further treatment were selected as a control group. Pure-tone audiometry results were obtained before and after treatments. Minimum follow-up time from the last treatment was 1 month. There were no serious adverse events in the treatment groups. Hearing improvement rate (HIR) of SSNHL in perfusion group was 40.6 %, which was significantly higher than in the injection and control groups (20.6 and 7.7 %, respectively). HIR had no relation with sex, age, and associated symptoms. Results indicated that intratympanic dexamethasone perfusion by external electronic pump with gelatin sponge placement in round window niche is an efficacious and safe method for the treatment of RSSNHL, showing superiority to simple injection through the drum.