A statistically significant improvement in PTA values (mean change 20.4 dB) was noted (p = 0.0002). In all, 13/25 (52%) patients exhibited improved bone conduction postoperatively regardless of age and time of treatment. A marked recovery (≥30 dB) could be seen in eight patients (median time to surgery, 9 days; average age, 48.5 years); recovery between 10 and 30 dB in five patients (median time to surgery, 10 days; average age, 46.6 years). Twelve significantly older patients showed no improvement (average time to surgery, 19 days; average age, 61.8 years; p = 0.004). No patient over the age of 65 years showed improvement in bone conduction.

In Group A the PTA improved by ≥10dB in 21/25(83%) cases; in Group B 18/28(63%). Group A showed a statistically significantly better improvement across all frequencies, while linear regression revealed a significant decrease of posttherapeutic PTA to 94.96% of the initial PTA (p = .037). The overall PTA improved by 24dB. Group A improved from 73dB to 41dB(-32dB) PTA, Group B improved from 76dB to 56dB PTA (-20dB) (p < .05). Group A showed a significant additional decrease of 12.8dB (p < .001).