Imaging Before Seton Removal Decreases Operative Reintervention in Patients With Perianal Crohn’s Disease

The timing of seton placement and removal, whether and what imaging studies should be used to guide seton therapy, and the ideal type and duration of medical treatment are controversial.1,2 MRI and EUS imaging have been shown to demonstrate ongoing fistula activity despite clinical remission and cessation of fistula drainage. 3 This subclinical inflammation may predispose patients to recurrent perianal symptoms and repeat EUAs, decreasing quality of life and increasing the financial burden for both patients and the health care system. Of the 13 MRIs performed, 9 reported improvement in or lack of fistula activity, described as “interval improvement”, “healing”, “near resolution” or “resolution”, “decrease in size of fluid collection” or “no fluid collection”, “unenhancing”, and “decrease in inflammation” or “no inflammation”. Variable With Imaging (n = 22) Without Imaging (n = 22) P-value Sex 0.41 Male, n(%) 9(41) 13(42) Mean CCI score (SD) 0.55(1.0) 0.97(1.7) 0.31 Mean age at Diagnosis, year (SD) 17.9(14.0) 20.1(11.2) 0.52 CD phenotype 0.90 Strictuing, n(%) 5(23) 5(16) Penetrating, n(%) 4(18) 8(26) Inflammatory, n(%) 7(32) 10(32) Unkown, n(%) 6(27) 8(26) Biologic medication 0.28 Pre-Seton 12(55) 10(32) Yes, n(%) Current practice guidelines designed by the American Society of Colon & Rectal Surgeons (ASCRS), the European Crohn’s and Colitis Organisation (ECCO), and the American College of Gastroenterology (ACG) have focused more broadly on how best to treat Crohn’s-related perianal fistulas rather than specifying criteria for seton removal.1,2 The ASCRS mentions that in patients being treated with infliximab with the aim of fistula closure, the timing of seton removal is controversial. 2 The ECCO recommends evaluating response to treatment by clinical assessment (decreased drainage), sometimes in combination with MRI or anal endosonography. 1 Similarly, the ACG generally states that EUS and MRI may help guide therapeutic intervention, including seton removal, in perianal Crohn’s disease patients.