fig16

Figure 16. Sinonasal papilloma. (A) Coronal CT image of the sinonasal region in a patient with IP showing an expansile lesion with soft-tissue attenuation in the left nasal cavity, maxillary sinus, frontal sinus, and ethmoid sinus (arrow). Bony remodeling and dehiscence of the nasal cavity and sinus walls, as well as erosion of the ethmoid septa, are also evident; (B and C) Coronal T2-weighted and post-contrast T1-weighted MRI images of the same patient demonstrate CCP, visible as alternating curvilinear hypointense and hyperintense signals diffusely within the tumor (arrows). CT: Computed tomography; IP: inverted papilloma; MRI: magnetic resonance imaging; CCP: convoluted cerebriform pattern.