Introduction: Osteomas are usually benign, slow growing tumors of the bone. Cranial osteomas are seen at the outer layer of the bone. Osteomas are usually seen at paranasal sinuses, parietal bone, maxilla and mandible. Incidence is 0.43%. They are frequently asymptomatic, and the main complaint about osteomas is cosmetic. We would like to share a case of occipital osteoma which grows in 2 years period and treated surgically.

Case report: Our patients was a 20 years old male, found a mass by himself at back of his head 2 years ago. He appealed because the mass was growing. Examination show that he has a solid mass at the occipital bone, its size was 2 × 1 cm. He was neurologically intact. We performed CT and MRI scans and they show a mass, arising from the outer layer of the occipital bone, 23 × 13 mm in size and the preliminary diagnosis was an osteoma. He was operated in our institution, we resected the mass and made a cranioplasty surgery at the same session. The pathology confirmed the diagnosis of osteoma.

Discussion: Surgery is the first treatment option for osteoma when it is growing. The main aim of surgery is cosmetic concern. But histological diagnosis could only be done after surgery. Total excision provides cure.

Key words: Osteoma. Benign bone mass. Cranioplasty.