探讨3.0T MRI对直肠癌患者术前判断T、N分期以及测量直肠肿瘤下缘与肛缘间曲线距离的准确性。

经术前肠镜活检病理证实为直肠癌的患者53例，于术前行MRI扫描，进行T、N分期并测量肿瘤下缘与肛缘间的距离。以术后病理结果为标准，验证3.0T MRI评价肿瘤T、N分期的准确性；用MRI测量出的肿瘤下缘与肛缘曲线的距离与手术标本测量的结果相比较，找出两种结果的相关性。

MRI对直肠癌患者T、N分期判定的准确率分别为83.1%、67.9%，统计学分析显示与病理结果有较好的一致性。MRI测量肿瘤下缘与肛缘的曲线距离与手术标本测得的数值无明显统计学差异。

MRI对直肠癌患者术前T、N分期的判定以及测量肿瘤下缘与肛缘间的曲线距离有较高的准确性，对术前治疗及手术方式的选择有很好的指导意义。

To evaluate the accuracy of 3.0T magnetic resonance imaging(MRI)for preoperative T/N staging of rectal cancer and distance from the anal verge to the tumor.

3.0T MRI was performed in 53 patients with primary rectal cancer prior to surgery, and assess its value in T/N staging.The final pathological result of surgical specimen was taken as standard.To analyze the correlation between MRI and pathology results in respect of measuring the distance from tumor to anus margin.

The overall accuracy of T-staging and N-staging was 83.1% and 67.9%.There was no obvious difference between the result of T/N staging with MRI and postoperative histological staging.There was no significant statistical difference between MRI and resected specimens in determining the distance from the anal verge to tumor.

MRI could accurately evaluate preoperative T/N-staging of rectal cancer and assess the distance between the anal verge and the carcinoma.Therefore MRI is more reliable for preoperative treatment and selecting the optimum surgical modality for individual patient.