目的 观察不同原发肿瘤脑转 移瘤的MR表现。方法 以本院2013年1 月-2016年4月经临床、病理证实的125例 脑转移瘤患者为研究对象，均接受MR常规 平扫及增强扫描，观察比较不同原发肿瘤 脑转移瘤部位、数目、大小、形态、水 肿、信号等表现。结果 脑转移瘤部位： 共350个瘤灶，其中顶叶处最多(105个)， 其次是枕叶(81个)；肺腺癌脑转移瘤好 发于顶叶(55个)，小细胞肺癌好发于颞 叶(19个)，乳腺癌好发于脑干、小脑(20 个)。125例患者中多发病灶108例。不同 原发肿瘤患者脑转移瘤大小、瘤周水肿程 度比较差异有统计学意义(P＜0.05)。形 态：以圆形或类圆形为主(85例)。信号表 现：平扫T1WI等或略低信号，T2WI高信 号；以均匀强化为主(203个)。54例患者 加以SWI检查，SWI对瘤内出血检出率明显 高于平扫T1WI(P＜0.05)，SWI检出引流血 管11条，而T1WI显示5条。结论 不同原发 肿瘤脑转移瘤MR表现不同，为脑转移瘤来 源提供依据，同时MR增强扫描、SWI对脑 转移瘤诊断有重要作用。

Objective To observe the MR findings of brain metastases from different primary tumors. Methods 125 patients with brain metastases confirmed by clinic and pathology in our hospital between January 2013 and April 2016 were selected as study subjects. All patients received MR routine plain scan and enhanced scan. The sites, number, size, shape, edema and signal of brain metastases from different primary tumors were observed and compared. Results In terms of sites of brain metastases, there were a total of 350 tumor lesions, of which most were located in parietal lobe (105), followed by occipital lobe (81). Brain metastases from lung adenocarcinoma easily occurred in the parietal lobe (55), small cell lung cancer in the temporal lobe (19) and breast cancer in the brain stem and cerebellum (20). In 125 patients, there were 108 patients with multiple lesions. There were significant differences in the size of brain metastases and the degree of edema between patients with different primary tumors (P<0.05). Most shape was round or quasi-circular (85 cases). In terms of signal, plain scan showed equal or slightly low signal on T1WI, high signal on T2WI and most with homogeneous enhancement (203). 54 cases were examined by SWI, the detection rate of SWI to intratumoral hemorrhage was significantly higher than that of plain scan T1WI (P<0.05). 11 of the drainage vessels were detected by SWI, while only 5 were detected by T1WI. Conclusion The MR findings of brain metastases from different primary tumors are different, which provide evidence for the source of brain metastasis. Meanwhile, MR enhanced scan and SWI play an important role in the diagnosis of brain metastases.