Application Value Of 3.0T MRI In The Preoperative Staging And Assessment Of Rectal Cancer

Objective:To investigate the value of 3.0 T MRI in preoperative staging and evaluation of rectal cancerMethods:A total of 76 patients with rectal cancer who met the inclusion criteria in a treatment group of gastrointestinal surgery,Second Affiliated Hospital of Dalian Medical University from May 2017 to December 2018 were selected for prospective study and analysis.All patients were imaged with 3.0T MRI and phased array surface coil.Less residue diet 2-3 days before examination,fasting time>6 hours on the day of examination,and empty the contents of jejunum as far as possible;do not use drugs to inhibit intestinal peristalsis;do not use intestinal contrast agents.Then each patient was independently diagnosed by MRI and pathological diagnosis after operation,and the key data were recorded in real time by their own specific personnel.Finally,the accuracy of preoperative MR diagnosis of TN staging,distances from the lower margin of tumors to the anal margin of all patients was analyzed.PASW Statistics 19.0 statistical software was used for data statistical analysis,in which the measurement data were expressed as mean(x±S).Matched sample t test was used for comparison;Kappa test was used for consistency between MRI and pathology in diagnosis of T staging and paraintestinal lymph node metastasis,and Kappa>0.7 was considered to be more consistent;P<0.05 was the significant differenceResults:There were 9 cases of stage T1,15 cases of stage T2,32 cases of stage T3,14 cases of stage T4a and 2 cases of stage T4b diagnosed by MRI,9 cases of stage T1,22 cases of stage T2,28 cases of stage T3,15 cases of stage T4a and 2 cases of stage T4b diagnosed by pathology,and the sensitivity and specificity of stage T1,T2,T3,T4a and T4b diagnosed by MRI were 67%and 100%,68.2%and 92.6%,89.3%and 85.4%,80.0%and 96.7%,100%and 100%,respectively,with good consistency(Kappa=0.708,P<0.05).)The sensitivity and specificity of MRI in diagnosis of paraintestinal lymph node metastasis were 85.2%and 83.3%(Kappa=0.701,P<0.05)In 12 patients who underwent anal resection,there was no significant difference in the distance between the inferior margin of the tumors and the anal margin measured by MRI and the gross specimen after operation(<7 mm)(P>0.05)Conclusion:3.0 T MRI can accurately staging and evaluating rectal cancer patients before operation,and provide help for clinical diagnosis and treatment.