Aims: To analyze hearing results of surgical treatment of hearing loss associated with the congenital stapes ankylosis with or without malformations of ossicular chain.
Study design: Retrospective chart review.
Methods: The charts of 1369 stapedotomies performed by senior author (JH) from 1991 to 2006 were reviewed. In 40 cases operative findings were consistent with isolated congenital stapes fixation or associated with middle ear malformations. The modified stapedotomy technique was employed in 33 cases and malleo-vestibulopexy was used in 7 cases. Operative findings were standardized according to Cremers' classification. The outcomes of 40 surgeries were analyzed according to the 1995 AAO-HNS Committee on Hearing and Equilibrium guidelines. High frequency hearing results on 4, 8 and 12kHz were reported in addition to standard frequencies. Results of stapedotomies and malleo-vestibulopexies were calculated separately. Surgical complications were described.
Results: The mean post-operative air conduction (AC) was 33 dB, bone conduction (BC) 22 dB and speech reception thresholds (SRT) 31 dB. Closure of the air-bone gap (ABG) to within 10 dB was achieved in 24/40 (60%) of cases. Lack of improvement was observed in 3/40 (8%) patients. In 26/32 (81%) of cases with potential for bilaterally serviceable hearing it was achieved. In 24/40 (60%) of cases symmetrical hearing with interaural difference of less than 10 dB was demonstrated.
Conclusion: Significant hearing gain in patients with congenital stapes ankylosis makes surgical treatment a valuable adjunct or an alternative to hearing aids in selected cases.