ABSTRACT
Osteoma is relatively rare benign tumor of non-inflammatory origin having a circumscribed form, a definite periosteal covering forming a line of cleavage from adjacent structures and showing active participation of osteoblasts. The tumor commonly originates in a nasal accessory sinus or calvaria and may invade the orbit relatively early in its growth, causing ocular disability prior to localizing signs in the smus. We have reported a giant osteoma in an adult having right eye protrusion, pain and interference of eyeball movements. The mass was totally removed by transcranial route successfully with no development of significant complications. The mass was extremely hard, well circumscribed and extended into right frontal, ethmoidal sinuses and orbital cavity.
