Sound lateralization ability of patients with bilateral microtia and atresia after bilateral reconstruction of auricles and external auditory canals and fitting of new canal-type hearing aids to replace a bone conduction hearing aid

Abstract

Conclusion: Each of eight patients with bilateral microtia and atresia underwent bilateral reconstruction of the auricles and external auditory canals and were fitted bilateral canal-type hearing aids in the operated ears to replace a bone conduction hearing aid. The ability to discriminate inter-aural intensity difference (IID) and even inter-aural time difference (ITD) was retained in all these patients.Objective: This study studied the post-operative sound lateralization ability of patients with bilateral microtia and atresia after total reconstruction of both auricles and external auditory canals, followed by fitting of bilateral canal-type hearing aids.Methods: Eight patients with bilateral microtia and atresia ranging in age from 13–43 years were recruited in this study. Each of them underwent bilateral reconstruction of the auricles and external auditory canals and were fitted canal-type hearing aids in both the operated ears to replace a bone conduction hearing aid. A sound lateralization test was conducted to determine IID and ITD discrimination ability thresholds.Results: In all the patients, the IID discrimination ability thresholds of the patients were more than 3-fold those of the controls, the ITD discrimination ability threshold was more than 5-fold those of controls, and binaural hearing was retained.