Objective To study the CT performances and literature review of myoepithelioma (ME)of the parotid gland,to improve the recognition and diagnostic accuracy of this disease.Methods The CT findings of 1 2 cases with ME of the parotid gland confirmed by surgery and pathology were analyzed retrospectively,the characteristics of the age of onset,gender,size,location,density,boundary and enhancement were analyzed.And then,the related literatures were reviewed.Results Among the 1 2 patients,5 were male and 7 were female,age ranged from 11 to 68 years old,with a median age of 45.2 years.2 patients had the symptom of tenderness and fever, and the other 10 patients were asymptomatic and painless preauricular mass,2 of which were gradually enlarged.All the tumors were single in this study,2 had visible capsule infiltration or unclear boundaries,and other 10 had intact or smooth edges.CT showed that the masses all located in the parotid gland(1 in the deep lobe and 11 in the superficial lobe).The diameter of the tumor was 10 mm to 50 mm,with an average of 29.1 mm.The density was uniform in 2 cases and irregular cystic degeneration and necrosis in the other 10 cases.Mild enhancement was found in the arteriovenous phase after enhanced scanning,in which 8 cases had marginal enhancement or nodular enhancement in the arterial phase,and gradual filling into the center in the venous phase.Conclusion The CT performances of ME of the parotid gland have define characteristics.The possibility of myoepithelioma of the parotid gland should be taken into account when it has continuous centripetal reinforcement after enhancement,combing with the single cystic solid mass with clear boundary in superficial lobe of the parotid gland.Malignant myoepithelioma (MM)should be considered when the tumor envelope is incomplete or the boundary with the surrounding structure is not clear.

Objective To investigate the MRI features of solitary fibrous tumors(SFT)in the spinal canal.Methods MRI images of 5 cases with pathologically proved STF in the spinal canal were analyzed retrospectively.Results Of 5 lesions,there were 2 in the cervical spine,3 in the thoracic spine;1 in the epidural space and 4 in the subdural extramedullary space.On MRI plain scan,3 lesions showed homogeneous iso-intense signal on T1WI and hypo-intense signal on T2WI,2 lesions showed heterogeneous signal,1 showed patchy hypo-intense signal on T1WI and T2WI at the upper edge of lesion,which had been confirmed as hemorrhage and the other lesion showed internal cystic variation.All of the 5 lesions enhanced on enhancement scan,with moderate enhancement in 2 lesions and significant enhancement in 3 lesions.Cystic and hemorrhagic area were not enhanced.The"dural tail sign"was showed in 3 cases.Conclusion The diagnosis of SFT should be considered when a lesion shows a localized solitary mass in the spinal canal with hypo-intense on T2WI and moderate to significant enhancement.