摘要目的:探讨3.0 T磁共振成像(MRI)对直肠癌环周切缘(CRM)的评估价值。方法:抽取绍兴市人民医院(浙江大学绍兴医院)2016年3月至2018年5月收治的病理检查明确的直肠癌患者105例为观察对象，术前均行MRI检查，与术后病理检查的CRM进行评估，分析MRI对CRM评估的准确率、灵敏度、特异度、阳性预测值和阴性预测值。结果:术前MRI评估CRM与术后病理结果一致92例；术前评估阳性，术后显示阴性12例；术前评估阴性，术后显示阳性1例。其准确率为87.62%(92/105)，灵敏度为50.00%(1/2)，特异度为88.35%(91/103)，阳性预测值为7.69%(1/13)，阴性预测值为98.91%(91/92)。结论:MRI在评估CRM时准确率、特异度和阴性预测值较高，而灵敏度和阳性预测值偏低，其原因考虑与术中扩大切除范围有关。

abstractsObjective:To evaluate the clinical value of 3.0 MRI imaging in evaluating the circumferential margin of rectal cancer.Methods:From March 2016 to May 2018, 105 cases of rectal cancer with definite pathology in Shaoxing People's Hospital were evaluated by preoperative MRI and post-operative pathology.The accuracy, sensitivity, specificity, positive predictive value and negative predictive value were obtained.Results:The accuracy, sensitivity, specificity, positive predictive value and negative predictive value were 87.62%(92/105), 50.00%(1/2), 88.35%(91/103), 7.69%(1/13)and 98.91%(91/92), respectively.Conclusion:The accuracy of MRI in evaluating CRM is higher, the specificity and negative predictive value are higher, while the sensitivity and positive predictive value are lower.The reason is related to enlarging the resection scope during operation.Whether it will affect the prognosis of patients needs further follow-up results.