Role of MRI for Assessment of Anal Fistula

The role of MRI in imaging perianal fistula is to outline all hidden tracts and define the relationship of the fistula to the anal sphincter. A detailed assessment of the anatomic relationship between the fistula and the anal sphincter complex allows surgeons to choose the best surgical treatment thus significantly reducing recurrence of the disease or possible secondary effects of surgery, such as fecal incontinence. MRI also help in delineating associated abscesses, horse shoe and secondary tract alerting the surgeon about the complex nature of the disease and providing an excellent road map prior to surgery. MRI is well tolerated, non-invasive, painless and not embarrassing for the patient, thus has been made it the modality of choice in evaluating perianal fistulas. Aim of the study was to determine the type, extent, associated abscesses and relations of perianal fistula with the anal sphincter complex. To obtain critical information with MRI for the surgical decision.