STAPEDECTOMY - LONG-TERM HEARING RESULTS

The initial improvement in hearing following stapedectomy usually deteriorates with the passage of time. We studied the long-term results of stapedectomies performed on 42 patients (49 ears) between 1959 and 1969 who had a minimum follow-up of 18 years. Both air conduction (AC) and bone conduction (BC) thresholds progressively deteriorated over the long term. The degree of BC loss paralleled that expected from presbycusis alone. A greater deterioration was noted in the AC levels, producing a recurrent conductive hearing loss in the speech frequencies. Age at the time of surgery had no effect on the long-term outcome. Comparison of the average preoperative speech discrimination scores (SDS) to the 1-year postoperative SDS and the long-term SDS revealed a 1.1% and 16.7% drop, respectively. The improvement in the average speech reception threshold (SRT) obtained 1 year postoperatively deteriorated by less than 1 dB per year over the long term. Patients with a higher SDS (more than 95%) preoperatively fared better in the maintenance of speech discrimination than those with a lower SDS (less than 95%). The preoperative SRT level was predictive of the timing for the requirement of hearing amplification. The postoperative hearing deterioration appeared to be caused by presbycusis, combined with a recurrent conductive loss in the speech frequencies rather than cochlear otosclerosis. Although the decline in hearing following stapedectomy exceeds the rate of hearing loss due to presbycusis, many individuals, after successful stapes surgery, are able to delay the need for hearing amplification for longer periods than had been previously reported.