CT images of a patient with inverted papilloma CT images of a patient with inverted papilloma.A and B, Axial and coronal CT images show focal plaquelike hyperostosis in part of right ethmoid sinuses (arrows).C, Although tumor extends to the right maxillary sinus and nasal cavity, no additional foci of h... CT images of a patient with inverted papilloma.A and B, Axial and coronal CT images show focal plaquelike hyperostosis in part of right ethmoid sinuses (arrows).C, Although tumor extends to the right maxillary sinus and nasal cavity, no additional foci of hyperostosis are seen. Intraoperative endoscopic examination confirmed the limitation of tumor origin to the ethmoid sinuses. D.K. Lee et al. AJNR Am J Neuroradiol 2007;28:618-621 ©2007 by American Society of Neuroradiology