原发性中枢神经系统淋巴瘤的CT和MRI表现

目的:探讨原发性中枢神经系统淋巴瘤的影像特征.方法:回顾性分析19例经病理证实的原发性中枢神经系统淋巴瘤CT和MRI表现.结果:19例中瘤灶31个,单发14例,多发5例;其中脑表面12个,室管膜旁13个,脑深部6个.CT检出26个病灶,检出率83.9%.CT表现呈等或稍高密度,19个密度均匀,7个密度不均.MRI检出所有31个病灶,检出率100%.肿瘤MRI 表现T1WI 信号略低于灰质,T2WI信号与灰质相似,22个信号均匀,9个信号不均.80.6%瘤灶表现为明显实质样强化,16.1%病灶伴脑膜或室管膜强化.占位效应以及瘤周水肿程度大多数为轻到中度.结论:大多数原发性中枢神经系统淋巴瘤有一定的影像学特征,少数不典型者鉴别困难.

CT and MRI of primary central nervous system lymphomas

Objective:To explore the imaging features of primary central nervous system lymphomas(PCNSL) by CT and MRI.Methods:The imaging data of CT and MRI of 19 patients with pathologically proved PCNSL were retrospectively analyzed.Results:Fourteen cases had single lesion and 5 had multiple lesions.A total of 31 lesions were detected.Twelve lesions were on the surface of the brain,13 were about the ependyma and 6 in the depth of the brain.Twenty-six lesions were detected by CT,with a detection rate of 83.9%.Thirty-one lesions were detected by MRI,with a detection rate of 100%.T_1WI and T_2WI showed that the intensity of the tumor was similar to the gray matter and 22 lesions were homogeneous and 9 were inhomogeneous.Enhancement showed that 80.6% lesions were remarkably matter-enhancing,16.1% lesions had enpendymal or meningeal enhancement.The perifocal white matter edema and the mass effect were mild to moderate in most cases.Conclusions:CT combined with MRI findings can help to make preoperative diagnosis in most cases;however diagnosis of rare atypical cases is difficult.