[Osteoma and exostosis of the external auditory meatus: a clinical diagnosis]

Proliferative osseous lesions usually found in the external ear are exostoses and osteomata. In other sites they are clearly different entities, but in this location histopathologic differential features are not so reliable in the study of the specimens. An occlusive osteomata is shown, with the typical clinical presentation demonstrated in a multiplanar CT. Microscopically, the lesion consisted of mature bone trabeculae, separated by medular spaces with fibrovascular tissue, characteristic features of osteomata. However, in the most superficial areas, lines of bone apposition, like those in exostoses, were found. A literature review confirms the lack of specificity of the histopathologic study, so diagnosis is based on clinical data.