Osteomas and exostoses of the external auditory canal - medical and surgical management.

Osteomas and exostoses have distinct clinical and histopathologic features. Osteomas are usually solitary, pedunculated, bony growths attached to the tympanosquamous or tympanomastoid suture line, characterized histologically by an internal structure of abundant discrete fibrovascular channels surrounded by irregularly oriented lamellated bone. Exostoses are usually multiple, bilaterally symmetrical, broad based elevations of bone involving the tympanic bone. They are histologically characterized by parallel, concentric layers of subperiosteal bone. The infrequent symptoms resulting from these lesions can usually be managed medically; however, on occasion surgical removal is indicated. While surgical removal of the osteoma is usually possible via the external auditory meatus, we recommend that an exostosis be removed utilizing a postauricular approach.