Inverted squamous papilloma with neuro-ophthalmic features.

The schneiderian or inverted papilloma is an infrequent and usually benign tumor of the paranasal sinuses. It most commonly manifests as unilateral nasal obstruction. This is a case of an inverted papilloma in a 92-year-old woman who presented with severe proptosis, loss of vision in the left eye, and rhinorrhea. The mass was visible in her left nostril; neuroimaging studies showed that the lesion extended from the left paranasal sinus into the frontal sinuses. In addition, there was secondary spread into the cranial cavity and brain substance.