Sino-Orbital Osteoma With Osteoblastoma-Like Features.

An 18 year old male presented with worsening headaches, pain with ocular movement and swelling that involved the left anterior periorbital and frontal sinus region. Radiographic images revealed a polypoid bony mass of mixed radiodensity extending into the left and right frontal sinuses. Histologic examination of the resection material resulted in the diagnosis of an osteoma with osteoblastoma-like features, an osteoma variant that has zones indistinguishable from an osteoblastoma. The clinical, radiographic, and morphologic features of sino-orbital osteoma with osteoblastoma-like features are discussed.