A Giant Frontal-ethmoid Sinus Cyst with Intracranial Involvement

We report a case of a 69-year-old woman with a giant frontal-ethmoid cyst with intracranial involvement. Without any previous operation or trauma, she complained of swelling in the medial angle of the left eye. Based on CT and MRI images, a giant cystic lesion was seen in the left frontal sinus and both ethmoid sinuses, which had caused a defect in the posterior wall of the cranial bone. The giant cyst pressed against the left frontal lobe of the brain. We opened the cystic wall solely by endoscopic technique and gently drained the cystic contents. After the operation, the sinus cavity was cured without herniation of the brain. There has been no recurrence for 7 years and 6 months.