Typical MR features and interpretation of perianal fistulas in patients with Crohn’s disease

•Perianal fistulas in Crohn’s disease (PFCD) are caused by different pathophysiology from cryptoglandular theory of non-CD perianal fistulas often represents complex phenotype with more complicated and multiple-branched fistulas than those of non-CD fistulas.•MR imaging provides detailed information regarding PFCD and structured reporting would be recommended for more complete interpretation of PFCD.•The comprehensive approach comprising clinical exam, endoscopy, and MR exam can assist individualized and multidisciplinary treatment planning in consideration of fistula anatomy and presence of proctitis, that is disease activity of Crohn’s disease.