Evaluation of anorectal fistula using an MRI fistulogram and its correlation with intraoperative findings

  • Received 28.12.2025
  • Revised 22.04.2026
  • Accepted 26.05.2026
  • Published 29.05.2026
  • 60 Views
  • Retrieved from Vol. 12, No. 1, 2026
  • Pages 44-54

Despite magnetic resonance imaging being the preferred modality for the preoperative assessment of fistula-in-ano, evidence from direct MRI-intraoperative correlation remains essential to confirm that internal openings, secondary tracts, and abscesses are accurately mapped, thereby preventing missed disease and recurrence. This study aimed to evaluate the correlation between magnetic resonance imaging findings and intraoperative observations in patients with anorectal fistulas. This prospective study was conducted at Al Amin Medical College and Hospital, including 50 patients with clinically suspected or previously diagnosed perianal fistula who underwent magnetic resonance imaging on a 1.5  Tesla scanner using T1-, T2-, short inversion recovery, and diffusion-weighted imaging sequences. Findings were analysed for fistula classification, tract location, internal openings, abscesses, and contrast enhancement. Surgical exploration findings were compared with magnetic resonance imaging results to assess correlation. The most affected age groups were 31-50 years, with a male predominance (66%). Intersphincteric (42%) and transsphincteric (36%) fistulas were the most common. Magnetic resonance imaging showed single internal and external openings in 86% of patients. Associated abscesses were detected in 20%, and contrast enhancement was noted in 46%. Magnetic resonance imaging demonstrated 100% sensitivity and specificity for internal openings, 90% sensitivity for abscesses, and 76.5% sensitivity for secondary tracts. Magnetic resonance imaging findings correlated with intraoperative findings in 86% of cases. Magnetic resonance imaging is a highly effective tool for evaluating fistula-in-ano, showing strong concordance with surgical findings. Its routine use can significantly enhance surgical planning and reduce recurrence rates

preoperative imaging; surgical correlation; perianal fistula; perianal abscess; internal opening

https://doi.org/10.63341/ijmmr/1.2026.44
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