目的探究3.0T MRI在早期直肠 癌诊断及术前T分期中的应用。方法 选 取2012年12月至 2014年9月于我院经肠 镜活检为直肠癌、且术前行全腹部MRI 平扫+增强检查的病人120例,检查后一 周内行外科手术及病理学检查，以手术 病理为金标准，分析3.0 T MRI在早期 直肠癌诊断及术前T分期中的价值。结 果 120例直肠癌患者中，MRI T分期显 示：T1期8例，T2期37例，T3期54例，T4 期21例，病理T分期显示：T1期8例，T2 期35例，T3期56例，T4期21例，经Kappa 检验分析显示，两者具有较高一致性 (Kappa=0.710，P=0.000)，总的诊断正 确率为86.67%(104/120)；直肠癌术前 MRI T分期诊断正确率T3期为92.45%、最 高，T1期最低、为75%，诊断特异性为T3 期最高(98.35%)，诊断T4期的敏感性、 阴性预测率为100%；3.0T MRI结果与病 理检查结果显示肿瘤下缘与肛缘的距离 分别为(4.20±0.51)cm、(4.21±0.45) cm，差异无统计学意义。结论 3.0T MRI 可准确诊断早期直肠癌及T分期，对术前 评估及指导手术有重要意义。

Objective To explore the application of 3.0 T MRI in the early diagnosis and preoperative T staging of rectal cancer. Methods This study selected 120 cases cancer patients which proved by endoscopic biopsy and accepted full abdomen MRI plain scan and contrast enhancemen before surgery from 2012 December to 2014 September in our hospital, the surgical operation and histopathological examination were within one week after the MR scan. To analyzed the clinical value of 3.0 T MRI in the early diagnosis and preoperative T staging of rectal cancer by the gold standard of operation. Results 120 cases of patients with rectal cancer, MRI T stage showed: 8 cases of stage T1, 37 cases were T2 stage, 54 cases were T3 stage and 21 cases were T4 stage. Pathological T stage showed: 8 cases were T1 stage, 35 cases were T2 stage, 56 cases were T3 stage and 21 cases were T4 stage. The Kappa test shows, both of them have high consistency (Kappa=0.710, P=0), the diagnostic accuracy was 86.67% (104/120); the correct diagnostic rate of T3 staging rectal carcinoma by 3.0 T MRI was 92.45%, and was the highest; the correct diagnostic rate of T1 staging rectal carcinoma by 3.0 T MRI was 75%, and was the lowest; the specificity of T3 staging by MRI is the highest (98.35%), sensitivity, negative predictive diagnosis of stage T4 rate of 100%; the results of 3.0MRI and pathological examination showed edge of distance and anal margin of the tumor respectively (4.20±0.51) cm, (4.21±0.45) cm, there was no statistically significant difference. Conclusion 3.0 T MRI can accurately diagnose early rectal carcinoma and T staging, which has important significance on preoperative evaluation and prognosis.