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Abstract : Magnetic resonance imaging (MRI) has emerged as the investigation of choice for the preoperative evaluation of perianal fistulas. The objectives of this study were to assess the usefulness of MR imaging in the evaluation of various grades and types of perianal fistula, correlate with intraoperative findings, and evaluate its role in postoperative recurrence. A prospective observational study was conducted over a period of 18 months on 55 patients referred with suspicion of perianal fistula. Preoperative MR fisulography scanning findings of patients were analysed and compared with intraoperative findings. Intraoperative findings were consistent with radiological description for detection of tracts. MRI could correctly diagnose primary tracts in 53 out of 55 patients and branched tracts in 19 out of 21 cases. For the detection of abscesses (14% of cases) and horse shoe components (7% of cases), MRI showed 100% concordance with surgery. High concordance was noted between MRI and surgical findings in relation to both St James and Park’s classifications, with p values of 0.01 and 0.0002 respectively. In the detection of internal openings, MRI showed high sensitivity (96%), specificity (83%), and positive predictive value (94.5%) with respect to surgical finding. Preoperative MRI showed reduced postoperative recurrence of fistula with only 2 cases out of 55 showing recurrence after 1 year. Preoperative MR fistulogram improves diagnostic effectiveness in the assessment of fistulous tract courses by demonstrating the location of the fistula in relation to anal sphincters and correctly identifying internal openings, branch tracts, abscesses, and horse shoe components.It also reduces post-operative recurrence.