原发性中枢神经系统淋巴瘤的CT和MR诊断优势分析

CT and MR Diagnostic Advantages of Primary Central Nervous System Lymphoma

目的分析CT和MR对原发性中枢神经系统淋巴瘤的诊断优势。方法回顾性分析本院近5年内收治的24例原发性中枢神经系统淋巴瘤患者临床资料,对所有患者采取CT和MR诊断,观察影像学特点。结果 24例PCNSL患者单发病灶10例,多发14例;有20例位于幕上,4例同时累及幕上和幕下;共检出51个病灶,位于丘脑、胼胝体、基底节区等深部脑组织的病灶各8个,另有7个位于额叶、4个位于颞叶、3个位于枕叶、13个位于脑桥。有32个病灶为不规则团块状、11个为卵圆形、8个病灶为蝶翼型。病灶大小为0.6~9.4 cm,平均(4.87±0.23)cm。CT平扫发现6例肿块呈均匀高密度影,3例呈不均匀高密度影,3例呈均匀等密度影;51个病灶中有4个邻近颅骨骨质浸润,未见钙化。增强扫描发现所有病灶均明显强化,其中有4个强化不均匀。MR平扫发现:T_1WI有8例等信号,12例稍低信号;T_2WI呈等信号或稍低信号,但有6例为稍高信号,5例信号欠均匀,中心可见囊性病变;DWI均为高或稍高信号。增强扫描可见所有肿块均明显强化,其中包括6例囊性病变区周围强化呈明显的"环征",4例累及胼胝体的肿块呈明显的"蝴蝶状"强化、4例呈"缺口征"、2例呈"握拳征"、1例呈"尖角征"、1例为类圆形片状。结论原发性中枢神经系统淋巴瘤CT和MR表现均有独特的征象和优势,临床需结合两种方法提高原发性中枢神经系统淋巴瘤的确诊率。

Objective To analyze the diagnostic advantages of CT and MR in primary central nervous system lymphoma. Methods The clinical data of 24 patients with primary central nervous system lymphoma admitted in our hospital in recent 5 years were retrospectively analyzed. All patients were diagnosed by CT and MR, and the imaging features were observed. Results 24 cases of PCNSL patients with solitary lesion in 10 cases, multiple 14 cases; 20 cases of supratentorial and 4 cases involving the supratentorial and infratentorial; 51 lesions were found in the brain, corpus callosum, thalamus, basal ganglia and deep lesions of the 8, and 7 in the frontal lobe 4, located in the temporal lobe, 3 in occipital lobe, 13 in the. 32 lesions were irregular mass, 11 were oval, and 8 were sphenoid airfoils. The size of the lesion was 0.6~9.4 cm, with an average of （4.87±0.23）cm. Plain scan showed that 6 cases showed homogeneous high density shadow, 3 cases showed uneven high density shadow, 3 cases showed uniform uniform density shadow, 51 lesions had 4 adjacent skull bone infiltration and no calcifcation. CT scan showed that there were 4 cases of adjacent skull bone infltration. Enhanced scan showed that all lesions were obviously enhanced, of which 4 were inhomogeneous. MR plain scan showed that T1WI had 8 cases of equal signal, 12 cases had slightly low signal, T2WI showed ISO signal or slightly low signal, but 6 cases were slightly hyperintense, 5 cases were not homogeneous, and cystic lesions were visible in the center. DWI was all high or slightly high signal. Enhanced scanning showed all the masses were enhanced obviously, including 6 cases of cystic lesions showed obvious enhancement around the ＂ring sign＂, 4 cases of tumors involving corpus callosum showed ＂butterfy shaped＂ enhancement, 4 cases showed ＂gap＂, 2 cases showed ＂fist sign＂, 1 case showed sharp sign ＂, 1 case of circular sheet. Conclusion The CT and MR manifestations of primary central nervous system lymphoma have unique signs and advantages. The combination of two methods should be combined to improve the diagnosis rate of primary central nervous system lymphoma.