冷水反復刺激が誘因と考えられた外耳道外骨腫の2例

<p>External auditory exostoses, also referred to as “surfer’s ears,” primarily occur in cold-water surfers, and are associated with long-term exposure to cold water. There are few reports of external auditory exostoses developing in patients without any history of aquatic activities.</p><p>We report two cases of external auditory exostoses caused by repetitive cold-water stimulation. A 56-year-old man presented to us with otorrhea and hearing loss on the right side. He gave a history of being in the habit, for several years, of soaking in a cold bath up to his head after a sauna bath. The external auditory exostoses were observed bilaterally, and the patient was also diagnosed as having chronic otitis media in the right ear. We performed canaloplasty and tympanoplasty on the right side. At 10 months after the right ear surgery, we performed canaloplasty on the left side. After the surgery, the patient’s hearing was restored and the external auditory exostoses have not recurred. A 70-year-old woman presented with a 4-year history of ear fullness on the right side. She had been in the habit, for more than 15 years, of often spraying cold water into the right ear canal when she felt itchy in the ear. The external auditory exostoses were observed on the right side and the right external auditory canal was almost completely obstructed. We performed canaloplasty and removed an external auditory canal cholesteatoma. After the surgery, her symptoms were improved and the exostoses have not recurred.</p><p>External auditory exostoses are induced by repetitive exposure to cold water. Avoiding exposure to cold water is important to prevent exacerbation and recurrence of external auditory exostoses.</p>