ABSTRACT
Objective To investigate the MRI features and pathological findings of primary intracranial lymphoma and to improve the diagnostic accuracy.Methods MRI features and pathological findings were analyzed in 28 pathologically proved cases of primary intracranial lymphoma.All 28 cases were examined by MRI scanning and diffusion weighted imaging(DWI),among which 19 cases were examined by enhanced MRI scanning.Results MRI manifestations:(1)single type:intracranial single lesion,the most common site was nearly the middle area of deep brain or brain surface;(2)multiple type.Type Ⅱa:multiple lesions in regional distribution, often showed several small lesions around a larger lesion.Type Ⅱb:multiple lesions in diffused distribution,often showed scattered distribution without an obvious regional distribution.The shapes of lesion were mass-like,nodular or irregular.The lesions showed isointense or slightly hypointense on T1 WI,and isointense,slightly hyperintense or slightly hypointense on T2 WI.On DWI,the le-sions showed hyperintense.Most lesions showed obvious enhancement with fisting sign,incision sign,pointed sign,butterfly sign,long and stiff spicule signand comb sign.Pathology:the tumor cells were heteromorphic and spread around the vessels, and showed greater cellularity,big prominent nucleoli,and small lymphocytes.The immunohistochemical examination showed that all tumor cells were positive for CD20 and CD79a and negative for GFAP.Conclusion The MRI findings of primary intracranial lym-phoma are various.Careful analysis can improve the diagnostic accuracy of the disease,definitive diagnosis requires histopathological and immunohistochemical examinations.