Endonasal removal of a large ethmoidal cementoblastoma

Cementoblastoma is a benign tumour, which pertains to the family of fibro osseous lesions of the jaws. A small number of clinical reports of cementum containing tumours locating in the paranasal sinuses have been published during the last three decades. Ethmoidal cementomas often attain a large size; they can destroy surrounding bone, invade the orbit and the skull base and usually require radical surgery for complete excision. We present a new case of a large cementoblastoma located in the left posterior ethmoid in the close vicinity of the optic nerve canal. In the 40-year old woman, endoscopic endonasal computer-assisted surgery allowed for complete tumour removal. No intraoperative damage to the orbit and the optic nerve occurred. No residual tumour was found at the follow-up visit three years after the surgery.