ABSTRACT
PURPOSE: To evaluate the radiologic characteristics of sinonasal lymphoma, as seen on CT and MR MATERIALS AND METHODS: In eighteen patients with pathologically-proven non-hodgkin's lymphoma in the sinonasal cavity, CT andMR images were retrospectively reviewed. CT and MR findings were analyzed for tumor location, degree ofinfiltration into the adjacent structure, degree of enhancement, and the presence of bone change. Tthe last-namedwas classified as one of four types : complete destruction, segmental destruction, thinning, or sclerotic change. RESULTS: Masses in the nasal cavity (N=17) and ethomoid sinus (N=16) were most common, and the remainder wereaccounted for by maxillary sinus(N=6), sphenoid sinus(N=2), and frontal sinus(N=2), In 16 cases, the involvementof more than two sinonasal compartments was demonstrated ; the deensity of these masses was shown by precontrastCT to be similar to that of facial muscles ; affer contrast enhancement, all except one (15/16) showed homogeneousenhancement. Tumor infiltration of the adjacent structure was identified in the nasopharynx(N=9), anterior buccalspace(N=7), orbit(n=6), subcutaneous layer of the cheek(N=3), and infratemporal fossa(N=3). Direct extension ofthe tumor from the nasal fossa to the nasopharynx or anterior buccal space was demonstrated. Among 18 cases, bonechange was seen in 12, segmental destruction in eight, complete destruction in six, thinning in two, and scleroticchange in two. Four of the six cases with complete bone destruction showed hyperdense linear density within themass ; CT showed that after treatment, bony regrowth had occurred. In two cases, MRI showed intermediate signalintensity of the masses on T1WI, iso or slightly high signal intensity on T2WI, and moderate enhancement onpostcontrast T1WI. CONCLUSION: On CT, sinonasal lymphoma usually showed homogenous enhancement, extensivelyinfiltration of the adjacent structure, but no massive bone destruction. Hyperdense linear density, suggestingghost bone and seen in spite of massive bone destruction, may be a characteristic finding of sinonasal lymphoma.