Role of MRI in assessment of perianal fistula


  • Haven Azo Mohammed Department of Surgery, College of Medicine, Hawler Medical University, Erbil, Iraq.
  • Hayam Yousif Odish Department of Surgery, College of Medicine, Hawler Medical University, Erbil, Iraq.



MR, Perianal fistula, Intersphincter, Transphincter


Background and objective: Perianal fistulae commonly occur in middle-aged men. It is important to determine the presence of fistula tracks, its grading and presence of abscess or inflammation. This study aimed to assess the role of MRI in diagnosis and classification of perianal fistula.

Methods: This study included 20 patients with perianal sepsis that were referred to the MRI section of Radiology Department in Rizgary Teaching Hospital between August 2015 and April 2016. All patients underwent MRI examination.

Results: The mean ± SD age of the 20 patients was 38.5 ± 10.4 years (range 22-55 years), of which 16 patients (80%) were males and four patients (20%) were females. Eighteen patients had a single external opening and two patients had two external opening. All the simple non-branching fistulas were successfully identified by axial and coronal planes of contrast enhanced T1Weighted image fast spin echo, of which five cases had simple intersphincter (G1) fistula and two had simple transphincter (G3), seven cases had intersphincter fistula either secondary tract or horse shoe and abscess (G2), five cases had complex transsphincter (G4). Two cases of complex G4 type had inflammation and edema in ischiorectal and ischioanal fossa and the internal openings were clearer in STIR T2axia.

Conclusion: MRI non-invasively offers important information about perianal fistula that can reduce surgical complications and postoperative recurrence of the disease. Every patient with suspicious perianal sepsis should undergo MRI examination to prevent complications and morbidity.


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Torkzad MR, Karlbom U. MRI for assessment of anal fistula. Insights Imaging 2010; 1(2):62-71.

Joshi AR, Siledar SG. Role of MRI in ano-rectal fistulas. Curr Radiol Rep 2014; 2:63.

Abcarian H. Anorectal infection: abscess-fistula. Clin Colon Rectal Surg 2011; 24(1):14-21.

Bhaya AK, Kumar N. MRI with MR fi stulogram for perianal fistula: A successful combination. Clin Gastrointest Magnetom 2007; 1:56-9.

Poggio JL. Fistula-in-ano. Emedicine; 2015. (Accessed March 12, 2016). Available at:

Tabry H, Farrands PA. Update on anal fistulae: surgical perspectives for the gastroenterologist. Can J Gastroenterol 2011; 25(12):675-80.

Woodburne RT. Essentials of human anatomy. 7th ed. Oxford, England: Oxford University Press; 1983.

Gage KL, Deshmukh S, Macura KJ, Kamel IR, Zaheer A. MRI of perianal fistulas: bridging the radiological-surgical divide. Abdom Imaging 2013; 38(5):1033-42.

Alaat El, Essawy MT. Magnetic resonance imaging in assessment of anorectal fistulae and its role in management. J Gastroint Dig Syst 2013; 3:139.

Halligan S, Stoker J. Imaging of fistula in ano. Radiology 2006; 239:18-33.

Morris J, Spencer JA, Ambrose NS. MR imaging classification of perianal fistulas and its implications for patient management. Radiographics 2000; 20:623-35.

Park AG, Gordon PH, Hardcastle JD. A classification of fistula-in-ano. Br J Surg 1976; 63:1-12.

Adurthy P, Prabhu SD, Kumar A. MRI in Assessment of Perianal Fistula. Indian J Applied Research 2016; 6(1):502-3.

de Miguel Criado J, del Salto LG, Rivas PF, del Hoyo LF, Velasco LG, de las Vacas MI, et al. MR Imaging Evaluation of Perianal Fistulas: Spectrum of Imaging Features. Radiographics 2012; 32(1):175-94.

Stoker J, Rociu E, Wiersma T, Lame´ ris J. Imaging of anorectal disease. Br J Surg 2000; 87:10-27.

Joyce M, Veniero J, Pokala R. Magnetic resonance imaging in the management of anal fistula and anorectal sepsis. Clin Colon Rectal Surg 2008; 21(3):213-9




How to Cite

Mohammed, H. A., & Odish, H. Y. (2018). Role of MRI in assessment of perianal fistula. Zanco Journal of Medical Sciences (Zanco J Med Sci), 21(2), 1789–1795.



Original Articles