Use of intratympanic dexamethasone for the therapy of low frequency hearing loss.

The objective was to assess the efficacy of intratympanic dexamethasone in treatment of sensorineural hearing loss at lower frequencies (LFSHL). The design is a prospective study. Eleven female and three male patients with LFSHL were included in this study. They were evaluated with pure-tone audiometry, acoustic admittance, transient evoked otoacoustic emission, and glycerol test. Seven, four, and three patients were seen within the mean of 2.86 +/- 1.35 (1-5), 18.25 +/- 2.36 (15-20), and 750 +/- 700 (60-1,460) days from onset of LFSHL, respectively. They were treated with daily intratympanic dexamethasone (ITD) injection and reviewed with repeated daily audiograms during the intratympanic treatment. As complementary treatment, they were given oral prednisolone 1 mg/kg (maximum 60 mg), with 10 mg decreasing doses for every 3 days. Results were compared with their unaffected ear. The mean +/- SD hearing level at 0.125 up to 1.5 kHz improved from 64.29 +/- 19.18 to 25.93 +/- 13.54 (P < 0.001), pure tone average improved from 62.7 +/- 25.7 to 22.9 +/- 17.8 (P < 0.001), speech reception thresholds improved from 34.6 +/- 29.45 to 17.5 +/- 16.38 (P = 0.028), speech discrimination scores improved from 65.7 +/- 39.8 to 84.6 +/- 24.7% (P = 0.024) with treatment. Complete recovery in 10 of 14 patients, partial recovery in 3 patients, was achieved after therapy; and in one patient the situation was unchanged. The mean hearing level at 0.125 up to 1.5 kHz was elevated from 45.6 +/- 17.5 to 9.1 +/- 10.3 dB (P < 0.001) when compared with unaffected ear. The mean recovery rate was 77.9 +/- 25.3%. ITD is an effective therapy for LFSHL.