Malignant neoplasm of maxillary sinus [C31.0], Reason for Study: ^Reason: sinus tumor History: headache and diplopia. There is relatively well circumscribed left frontal sinus mass which extends toward left ethmoid sinus through the left frontoethmoidal recess. The mass shows low signal intensity on both T1 and T2 images. It demonstrates grossly homogenous enhancement with some central non-enhancing area indicating possible central necrotic area. The mass is measured about 19.3mm (RL) x 29.5mm (AP) x 27.9mm (CC).The mass bulges into the orbit and pushes left side orbital fat and left superior oblique muscle. There is no fat place seen between the mass and superior oblique muscle about 9mm length especially anterior aspect (series 1201, image 12 to 14).The left medial rectus appears to be clearly separated from the mass with orbital fat plane. Thin linear low signal intensity at both left lamina papyracea and posterior wall of frontal sinus on T2 images indicating remained intact cortical bone. However, the boney intactness can be better evaluated through thin section CT scan.There are evidence of bilateral maxillary sinus antrostomy with mucosal thickening at the left maxillary sinus.T2 high signal intensities at the superior aspect of the left frontal sinus is likely represent trapped sinus space due to sinus mass described above. Imaged brain appears to be unremarkable except multiple tissue losses on the right cerebellar hemisphere indicating prior ischemic infarction.
Interval growth of the left frontal sinus enhancing mass extends toward left ethmoid sinus and left mesial aspect of the orbit indicating recurrent sinus tumor. Other differential diagnosis include new slowly growing sinus tumor or metastasis. The possibility of inflammatory or infectious lesion is unlikely.