Clinical Validation Of (Quantitative Synthetic MRI Imaging) Synthetic MRI In Evaluating Rectal Cancer:Preliminary Application

Objective: To explore the clinical value of quantitative synthetic MR imaging in the diagnosis of rectal cancer.Method: 100 cases of rectal adenocarcinoma confirmed by postoperative histopathology were collected.All the patients underwent preoperative rectal MRI examination,and the scan protocol include additional rectal Synthetic MRI.Within a week after the examination,all patients underwent TME resection for rectal cancer.The primary rectal lesion and extramural venous invasion(EMVI)in rectal cancer were analyzed using the Synthetic MRI imaging and the T1,T2,and PD values were recorded.Extramural venous invasion(EMVI)score was also evaluated.T test and rank sum test were used for statistical analysis.P < 0.05 was considered statistically significant.The diagnostic efficacy was evaluated using the ROC curve,and AUC value was used as the criterion.Result: Compared with the normal rectal wall,T1 and T2 values were higher in rectal cancer(P < 0.05),and T2 values were more effective(AUC=0.744,95%CI=0.639～0.850).Compared with the EMVI-negative patients,the T1 value in the fat space around the lesions of the EMVI-positive patients was higher,and the difference was statistically significant(P=0.000),and the(0.787,95%CI=0.693～0.882)indicated a higher diagnostic efficiency.The T1 value of perirectal cancer fat increased gradually with the increase of EMVI score(P=0.000,r =0.519).Conclusion: Synthetic MRI can be used in the diagnosis of rectal cancer,and T2 value has a good diagnostic effect.T1 value has a better diagnostic effect on EMVI of rectal cancer,and EMVI can be graded.