Clinical Study Of MRI On The Clinical Features And Therapeutic Effects Of Perianal Fistula In Crohn’s Disease

Background:Clinical assessment of the degree of healing of perianal fistula in Crohn’s disease(CD)is not accurate according to fistula secretions.The high signal intensity of the fistula in imaging may be the main reason for the high recurrence rate after the clinical healing of perianal fistulizing Crohn’s disease(PFCD).Magnetic reasoning imaging(MRI)can clearly show the relationship between the fistula and the tissue around the anorectal rectum,is considered to be the gold standard for assessing the healing of PFCD.The MRI-based Van Assche score can accurately and objectively assess the perianal fistula morphological characteristics,whether it is associated with abscess and rectal involvement,especially for clinical initial intervention strategies.Importantly,there is currently no correlation between the Van Assche scores and the clinical outcomes,and the scores are less predictive of clinical outcomes.At the same time,a large number of literatures have confirmed that the clinical healing of PFCD is 12 months deeper than MRI,and there are few studies on whether deep healing is achieved in patients with long-term clinical healing.Therefore,the prediction of the clinical outcome of PFCD based on the preoperative MRI Van Assche score and the correlation between deep healing under MRI and long-term clinical healing are the focus of this study.Objective:1.To evaluate the significance of the preoperative Van Assche score in patients with PFCD treated with IFX combined with seton placement therapy in predicting clinical outcomes;2.To explore the correlation between deep healing and clinical long-term healing under MRI in patients with PFCD treated with combination therapy and determine the predictors of deep healing.Methods:Prospective database retrospective study.CD patients diagnosed and treated in anorectal department of Nanjing university of traditional Chinese medicine from August 2010 to October 2016 were collected.Patients with PFCD who were treated with IFX combined with seton placement therapy and received at least preoperative MRI were included.MRI and clinical data were collected to analyze the significance of pre-operative MRI Van Assche score in predicting clinical outcomes in patients with PFCD,and each individual item in Van Assche score was evaluated by logistic regression model.To compare the correlation between deep healing and long-term clinical healing under MRI in patients with PFCD and other factors that may affect deep healing.Results:1.93 patients with PFCD who met the criteria were included in this study(male 73.1%).The median follow-up time was 34.5(IQR,22-58 months).The clinical healing rate and response rate were 60.2%(56/93)and 39.8%(37/93),respectively.The Van Assche score in the clinical healing group was relatively low(13.6 vs 16.4,P=0.005).2.The area under the ROC curve of clinical healing patients constructed according to the Van Assche score was 0.674,with sensitivity and specificity of 87.50%and 40.54%,respectively.The truncation value of Van Assche score was 18.0,and patients with>18.0 score were more likely to achieve clinical healing(OR=0.21,P=0.003).3.Ffifty-seven patients(39 males)with preoperative and follow-up end points of MRI imaging data were included in the further study.Long-term clinical healing rate and response rate were 57.9%(33/57)and 42.1%(24/57),respectively.Among the 33 patients with long-term clinical healing,16 cases(48.5%)achieved deep healing under MRI.4.Univariate analysis showed that there was a significant correlation between fistula located below the levator ani muscle and deep healing(P=0.047).Multivariate analysis showed that IFX maintenance treatment<3 times(OR=4.30,95%CI:1.16-15.94)and fistula with secondary track(OR=4.38,95%CI:1.12-17.04)were risk factors for deep healing.Fistula located below the levator ani muscle(OR=0.18,95%CI:0.04-0.82)is a protective factor for deep healing.Conclusion:1.There is a large difference between the Van Assche score and CD clinical healing of perianal fistula,which is not a reliable indicator to predict the clinical healing of patients.Patients with a preoperative Van Assche score of less than or equal to 18.0 may require closer follow-up or aggressive medication.2.The MRI deep healing of PFCD with IFX combined with seton placement therapy is inconsistent with the clinical long-term healing,and only 1/2 of patients with clinical long-term healing can achieve deep healing.IFX maintenance treatment>3 times and fistula without secondary tract and located below the levator ani muscle are protective factors for deep remission.