osteoma

Osteoma is a benign bone tumor characterized by the growth of mature, well-differentiated bone tissue. It typically develops slowly and is most often located in the skull and facial bones, especially the frontal sinus, ethmoid region, and mandible. Osteomas can arise on the outer surface of a bone (peripheral osteoma) or within the bone itself (central osteoma). They are usually solitary and grow gradually over years.

Many osteomas are asymptomatic and are discovered incidentally on imaging performed for unrelated reasons. When they enlarge or impinge on nearby structures, they can cause nasal obstruction or sinusitis, facial asymmetry, headaches, or diplopia depending on their location. Symptoms, if present, tend to reflect the lesion’s size and proximity to nerves, ducts, or ocular or sinus structures.

Diagnosis relies on imaging. Plain radiographs or CT scans typically show a well-circumscribed, radiodense mass consistent with compact or trabecular bone. CT is particularly helpful for outlining extent and relationships to adjacent structures, which guides treatment. MRI may be used to assess surrounding soft tissues when needed. Histology shows mature lamellar bone; biopsy is not always required if imaging is classic, though confirmation may be obtained in uncertain cases.

Treatment is generally conservative for asymptomatic lesions. Symptomatic or cosmetically concerning osteomas are usually surgically removed. Surgical approaches depend on location and may include endoscopic sinus surgery for paranasal sinus lesions or more extensive craniofacial approaches for skull or orbital involvement. Prognosis after complete excision is excellent, with a low risk of recurrence.

Gardner syndrome, characterized by multiple osteomas with intestinal polyposis, should be considered if multiple lesions are present, warranting broader clinical evaluation.