Surfer's Ear: Exostoses of the External Auditory Canal

Exostosis of the external auditory canal is an entity found exclusively in humans. Although well-documented in the otol­ ogy literature and briefly discussed in several medical texts, it has not been referred to or extensively discussed in radio­ logic journals. The clinical data and CT findings of a typical case are presented. Case Report A 56-year-old white male physician presented with a 5-year history of recurrent and intermittent hearing loss. The symptoms were pre­ dominantly right-sided and were increasing in frequency. Hearing loss was interfering with his ability to perform auscultatory examinations. He was able to temporarily restore hearing with the frequent use of carbamide peroxide drops. There was no history of prior ear infec­ tions; however, his medical history was significant for prolonged exposure to cold seawater in the form of swimming and body surfing . The exposure occurred over a period of 12- 15 years. Physical examinati on demonstrated severe bilateral external audi­ tory canal stenosis. Impacted cerumen was seen occluding the right external auditory canal. There were no signs of infection. Audiologic testing following disimpaction of the cerumen rev ealed no ab­ normality. CT was performed in both axial and coronal planes at 1-mm intervals. A multinodular bony mass was seen ari sing from both the anterior and posterior wall s of the right external auditory canal with a re sidual luminal diameter of 1 mm (Fig. 1 A). Similar findings were demonstrated on the left, although the bony proliferation was smoother and a re sidual luminal diameter of 2 mm was present (Fig. 1 B). The patient underwent excision of the exostosis in the right ear , creating a 3-4 mm lumen in the external auditory canal (Fi g. 1 C) . He made an uneventful recovery and has been symptom-free to date.