脑内原发性淋巴瘤MRI诊断

Diagnosis of Primary Lymphoma in the Brain with Magnetic Resonance Imaging

目的分析脑内原发性淋巴瘤MRI特点,旨在提高对该病的MRI诊断水平。方法分析12例经手术病理证实的脑内原发性淋巴瘤的MRI表现。结果(1)淋巴瘤呈单发(10例)或多发(2例),单发者部位包括额叶、颞叶、顶叶、基底节区及中脑;(2)T1WI呈低或稍低信号11例,T2WI呈等信号或稍高信号11例,1例出现坏死及出血;(3)灶周轻度到中度水肿,占位效应亦为轻至中度;(4)增强大多显著均匀强化,呈"握拳"样或团块状,1例环形强化,肿瘤可沿脑脊液播散。结论脑内原发性淋巴瘤的MRI多在大脑深部,明显强化,MRI表现具有一定的特异性,结合MRI影像特点和临床资料综合分析,一般可在术前作出正确诊断。

Objective To study retrospectively the MRI features of primary lymphomas in the brain for increasing diagnosis accuracy. Mothods MRI signs of 12 cases of primary lymphoma in the brain were studied retrospectively, these cases were proved by surgical pathology. Results （1） Twelve patients presented as single lesion in 10 cases and multiple lesions in 2 cases. The single lesions sited at the frontal lobe, temporal lobe, apical lobe, the basal ganglia and the middle brain. （2）The lesions showed hypo-intensity or mildly hypointensity on T1WI in 1 1 cases and iso-intensity or slightly hyper-intensity on T2WI in 11 cases. Necrosis and hemorrhage occurred in one case. （3） Most lesions showed mild to moderate peritumoral edema and mass effect. （4） On enhanced T1WI, majority displayed markedly homogeneous enhancement as ＂clench fist＂ sign or massive sign, except one case with circle enhancement, sometimes lesions spread along CSF. Conclusion MRI findings of primary lymphomas in the brain have some characteristics of the deep site of the brain, markedly enhancing. It is possible to make a correct preoperative diagnosis in most cases of primary lymphomas.