Ethmoidal osteoma with intraorbital extension: excision through a transcutaneous paranasal incision

PURPOSE: To describe a case of conjunctival hyperaemia and proptosis of the right eye. METHODS: Three-dimensional computed tomography (CT) was performed to reveal the size and position of a lesion of osseous density extending into the right orbit. The lesion was then excised using a right paranasal transcutaneous approach. RESULTS: The pathology report suggested ethmoidal osteoma. The postoperative course was uncomplicated and the lesion did not recur during a 5-year follow-up period. Repeated postoperative ophthalmic examinations revealed preservation of visual acuity and visual fields postoperatively. DISCUSSION: Diagnosis is based on imaging studies, especially CT and three-dimensional CT scans. A three-dimensional CT scan is critical in understanding the actual dimensions of the tumour and its relations with other structures. Surgical removal is indicated in cases with orbital matrix compression and displacement. A transcutaneous paranasal approach allows for increased exposure of affected structures.