FIG 1. 48-year-old man with deep facial pain, nasal obstruction, anosmia, and rhinorrhea 6 months after surgery for sinonasal polyposis associated with a frontal mucocele.

A–B, Coronal CT scans through the pterygoid process show enlargement of the left pterygoid canal (arrow, A) as well as enlargement of the left foramen rotundum (arrow, B).

C, Coronal CT scan more anterior than A and B shows widening and erosion of both infraorbital canals (asterisks). Note the presence of abnormal soft tissue in the maxillary and sphenoidal sinuses.

D, Contrast-enhanced axial T1-weighted MR image (700/12/6 [TR/TE/excitations]) through the base of the skull, obtained with a fat-saturation technique, shows abnormal enhancing tissue in the right and left upper pterygopalatine fossae (black asterisks). Enlargement and enhancement of the infraorbital nerves (white asterisks) and the left pterygoid nerve (arrowhead) can also be seen.

E, Contrast-enhanced coronal T1-weighted MR image (700/12/6) shows enhancement of the right and left vidian nerves (arrowheads), enlargement of the left vidian nerve, and left-sided maxillary division of the trigeminal nerve (arrow).

F, Contrast-enhanced coronal T1-weighted MR image (700/12/6) through the anterior part of the maxillary sinus shows enlargement and enhancement of both infraorbital nerves (asterisks). Abnormal enhancing tissue infiltrates through the skull base, involving the meninges in the anterior cranial fossa. Thickening of the sinus mucosa is visible on all images.