A rare case of oncocytic Schneiderian papilloma with intradural and intraorbital extension with notes of operative techniques.

Epithelial cells of cylindrical cell papilloma are oncocytes, which arise from the sinonasal respiratory epithelium, hence the term Oncocytic Schneiderian papilloma.This is a rare and benign neoplasm of the nose and paranasal sinuses and it should be considered in the work-up of all unilateral nasal polypoid lesions. Clinically behaviour is comparable to inverted papillomas for local recurrence and malignancy coexistence. We report a case arisen from the nasoethmoidal space that extended to the anterior skull base through a bone dehiscence with intradural invasion and orbital space involvement. Surgical therapy is the treatment of choice, the endonasal endoscopic approach can be used in most of the cases and this surgical technique is safe and suitable also in presence of an extra nasal extension. We describe our experience for management of this kind of lesions and some notes on our operative technique.