中文摘要：

目的：评价3.0 T MRI技术,特别是磁共振扩散加权成像技术及动态增强扫描对直肠癌诊断、分期及术前评估的临床应用价值。方法：回顾性分析了37例术前经结肠镜活检证实的直肠癌病人,行盆腔磁共振扫描,对直肠癌进行影像分期及术前评估,观察病变部位,探讨ADC值与直肠癌恶性程度的相关性及3.0 T磁共振常规序列及动态增强诊断相对于直肠镜检诊断直肠癌的优势分析。结果：MRI矢状位能清晰显示所有病例的肛缘距肿瘤下缘的曲线距离。37例不同分化程度的直肠癌的ADC值均随着肿瘤的分化程度减低而减低,两者具有相关性。不同分化程度组间ADC值的差异具有统计学意义（P=0.000）;高分化与中分化组间差异有统计学意义（P〈0.05）。高分化与低分化组间差异有统计学意义（P〈0.05）,中分化与低分化组间差异有统计学意义（P〈0.05）。直肠癌的磁共振表现及分期价值。结论：3.0 T MR能较准确的对直肠癌进行诊断及分期,更好的为临床医师制定术前方案提供科学依据。

英文摘要：

Objective： The clinical application value of 3. 0 T MRI techniques,especially magnetic resonance diffusion weighted imaging and dynamic enhanced scan for rectal cancer diagnosis,staging and preoperative evaluation. Methods： Retrospective analysis of 37 cases of preoperative patients with rectal cancer,which were confirmed by colonoscopy biopsy and scanning of MRI,an imaging staging and preoperative evaluation of rectal cancer,to observe the pathological changes,ADC values and rectal malignant degree of relevance and 3. 0 T magnetic resonance（ NMR） and dynamic enhance diagnosis compared with the conventional sequence advantage analysis of microscopic examination of the rectum in the diagnosis of rectal cancer. Results： Sagittal MRI can clearly show all cases of anal edge distance from the curve of the edge of the tumor. 37 cases of ADC values are differentiation degree of rectal cancer with reducing tumor differentiation degree and the correlation between the two. The difference of ADC values between different differentiation groups have statistical significance（ P = 0. 000）; In high differentiation and differentiation between group difference was statistically significant（ P〈0. 05）. Differentiation of high and low difference between groups was statistically significant（ P〈0. 05）,the difference between differentiation and low differentiation group was statistically significant（ P〈0. 05）.Magnetic resonance imaging（ MRI） can manifest of rectal cancer and staging. Conclusion： 3. 0 T MR can accurately in rectal cancer diagnosis and staging,better preoperative plan provided the scientific basis for clinical physicians.