原发性脑内淋巴瘤的影像学表现及病理对照

目的探讨原发性脑内淋巴瘤的影像学表现,以提高诊断的正确性。方法回顾性分析25例经病理证实的原发性脑内淋巴瘤的CT、MRI资料,并结合文献复习。结果单发18例,多发7例,共有43个病灶。单发病灶多位于脑白质深部,多发病灶常呈区域性分布,偏一侧半球近中线部位分布,如胼胝体、基底节区、丘脑。肿瘤在CT上多表现稍高密度,病灶T1WI多呈等或低信号,T2WI多呈等或稍高信号,DWI上多呈高信号。单个病灶多呈团块状或结节状强化,多发病灶呈斑点状或斑片状强化,且可见"缺口征"、"尖角征"、"握拳征"等淋巴瘤特征性表现,但出现率较低。瘤周轻度水肿14个、中度水肿21个、重度水肿8个。结论原发性脑内淋巴瘤的CT、MRI表现具有一定特征性,结合临床并综合其影像学表现,可提高其诊断准确率,最终确诊仍依赖于病理。

The CT, MRI Features and Differential Diagnosis of Primary Central Nervous System Lymphoma

Objective To explore the CT, MRI features of primary central nervous system lymphoma so as to inprove it＇s preoperiative diagnosis. Methods The CT, MRI Imaging 25 cases confirmed pathologically were analyzed retrospectively. Features of CT or MRI appearances of the tumors were studied, Results On CT, MRI imaging,single lesions were found in 18 cases and multiple ones in 7. The single or multiple tumors were seen com- monly located in deep alba, like callosum corpus, thalamus and basal ganglion. The lesions were iso-intensity or hyper-intenity by CT plain scan. The lesions were dense homogenous enhencement by motting iso-intense or slightly hypo-intense on T I weighted image while iso-intense or slightly hyper-intense on T2 weighted imaging by MRI plain scan. The lesions were hypo-intense on duffusion weighted image. Enhancement was intense and homogeneous such as clumping and nodosity. The presence of ＂incision sign＂, ＂angular sign＂ and ＂clench fist sign＂ were more specific. Conclusions The imaging findings of PCNSL has some characteristic, its diagnostic accurate rate can be improved by considering both the CT and MRI features and the patient＇s clinical information, the final diagnosis still depends on pathology.