Fig. 3

Axial T2-weighted MR image shows slightly hyperintense thickened mucosa in maxillary sinuses with concomitant retained secretions bilaterally (a). Preoperative coronal T1-weighted gadolinium enhanced MR scan. A multiloculated in homogeneously enhancing lesion protrudes from the left frontal sinus to the left frontal region, corresponding to a large mucocele (white arrows). Findings of superior and middle turbinectomy as well as bilateral maxillary antrostomy may be clearly depicted with slightly hyperintense thickened mucosa in both maxillary sinuses (b). Axial FLAIR MR sequence. A multiloculated lesion corresponding to a large mucocele, protrudes to the left frontal subarachnoid space, abutting the left frontal lobe (white arrows). The lesion shows internal areas of variable signal intensity, ranging from high to low (c). Brain CT in axial plane, bone window setting. The large mucocele causes an extensive erosion of the posterior wall of the left frontal sinus, protruding intracranially (black arrow) (d)