MR imaging of perianal fistulas in Crohn's disease: Sensitivity and specificity of STIR sequences

Introduction Although some studies proved the role of STIR sequences in the evaluation of perianal fistulas in Crohn's Disease (CD), contrast medium is still injected in many institutions since there is not a validated reference MR protocol. Our purpose was to evaluate the role of the STIR sequence in the detection and characterization of perianal fistulae comparing it to the post-contrast T1 sequence and correlating it with rectal examination under anesthesia. Materials and methods We retrospectively reviewed all clinical records of 31 CD patients, suspected of having perianal fistulas, who had been submitted to an MR study before and after contrast medium injection and surgical exploratio…