Otosclerosis: Shift in bone conduction after stapedotomy
A. Sabbe , N. Verhaert , I. Joossen , A. Lammens and F. Debruyne
Department of Otorhinolaryngology, Head and Neck Surgery, University Hospitals of Leuven, Leuven, Belgium; 2Department of Neurosciences, Research Group ExpORL, Master of Science in Speech and Language Pathology and Audiology Sciences, University of Leuven, Leuven, Belgium
Otosclerosis; bone conduction; Carhart notch
183 - 189
Otosclerosis: Shift in bone conduction after stapedotomy. Objectives: To analyze changes in bone conduction (BC) thresholds before and after stapedotomy in patients with clinical otosclerosis with a focus on the Carhart notch, which is defined as a significant loss of BC at a certain audiometric frequency. Methodology: Retrospective case review of pure tone audiometry (PTA) in 213 patients who underwent a stapedotomy at a tertiary referral center between 2004 and 2011. The patients were grouped by age and the frequency of the Carhart notch. The non-operated ear was also evaluated. Results: The Carhart notch was present on pre-operative audiometry in 158 (74%) patients at 0.5 (n=18, 8.45%), 1 (n=25, 11.70%), or 2 kHz (n=115, 54.0%). We measured a mean postoperative improvement in BC of 7.5, 8.4, and 8.8 dB HL. Pre-operatively, 55 (25.8%) patients did not exhibit a typical notch configuration. The mean gain in BC, defined on PTA according to the AAO-HNS criteria (0.5, 1, 2 and 3, or 4 kHz), was 1.8 dB HL after stapedotomy. Conclusion: The Carhart notch was not solely related to the 2 kHz frequency. The greatest gain in BC after stapedotomy for otosclerosis occurred at the notch frequency.
Vol. 11, 2015, 3rd trimester

Otosclerosis: Shift in bone conduction after stapedotomy