Less radical drilling in surgery for exostoses of the external auditory canal

Objective: To estimate the anatomical and functional long-term result of surgery for ear canal exostosis. Methods: Case rapport review with extraction of data concerning pre- and postoperative anatomical conditions, symptoms and audiology and a clinical and audiological re-evaluation. In the 20-year-period from 1 January 1976 to 1 January 1996, 26 patients were operated on primarily for ear canal exostosis. 19 patients with in total 24 ears were re-evaluated. Control-period 7.2 years. Pre-operatively were found occluding ear-canal exostosis in all patients as well as hearing loss, otitis externa and pain. Results: At the re-evaluation all patient were completely free of their symptoms. 19 out of 24 ears still had some remnants of exostosis, but the ear canal was covered with completely normal skin and had normal migration properties. No signs of re-growth were found in this material. Postoperatively one patient had a sensorineural hearing loss of 85 dB at 6 kHz, one had a dehiscence of the temporomandibular joint and one patient had an anterior ear drum perforation. Conclusion: To avoid the complications a less radical drilling of exostoses is proposed, in particular along the superior wall and near the short process of the malleus handle and along the anterior tympanomeatal angle. Removal of the bone from the posterior, inferior and anterior walls with preservation of the canal skin, creates enough lumen providing permanent cure.