目的　分析小脑半球脑梗塞的MR表现 ,明确诊断 ,指导临床治疗。方法　 2 0例 ,行MR矢、冠、轴位扫描 ,部分病例行增强扫描 ,并行治疗后复查 ,观察其MRI表现。结果　①由于小脑半球的供血来源不同 ,可出现小脑上动脉供血区 ,小脑前下动脉供血区 ,及小脑后下动脉供血区脑梗塞 ,其中后者最常见 ;②于MR矢、冠、轴位像上可清楚看到病灶的边界 ;③MR上表现为长T1,长T2 沿血管分布区异常信号 ,经临床治疗后 ,复查可见病灶缩小 ;④小脑半球脑梗塞可伴有其他部位脑梗塞。结论　MR对小脑半球脑梗塞的影像表现较CT优越 ,观察清楚 ,诊断明确 ,同时可进行临床治疗效果追踪观察 Objective To analyze the MR manifestations of cerebellar hemispheric cerebral infarction, confirm the diagnosis and guide the clinical treatment. Methods Twenty-one patients underwent MRI scan, coronal scan and axial scan. Some patients underwent enhanced scan and were retrospectively reviewed after concurrent treatment to observe their MRI findings. Results ① Due to different sources of blood supply in the cerebellar hemisphere, there may be cerebellar infarction in the superior cerebellar artery supplying area, anterior cerebellar artery supplying area and posterior inferior ceremonial artery supplying area, of which the latter is the most common. ② In MR vector, coronal, axial As the lesions can clearly see the border; ③ MR on the performance of long T1, T2 along the vascular abnormalities signal distribution, after clinical treatment, the lesser lesions can be seen; ④ cerebellar cerebellar infarction may be associated with other parts of the cerebral infarction. Conclusion MR imaging of the performance of cerebellar hemispheric cerebral infarction superior to CT, the observation clearly, the diagnosis is clear, at the same time be able to track the clinical effect of treatment