Juvenile ossifying fibroma: CT and MR findings.

We describe the CT findings in four patients and the MR imaging in one patient with juvenile ossifying fibroma. Three lesions involved the maxillary sinus and extended to the surrounding structures; one lesion was confined to the maxillary bone. CT scan revealed well-defined, expansile lesions with variable amount of calcifications. On MRI one lesion had intermediate signal intensity with significant contrast enhancement.