Role of magnetic resonance imaging in evaluation of perianal fistulas

Nilesh H. Chaudhari, Ameya D. Sinkar, Samparna Swoyam


Background: Perianal fistula is a common disorder that often recurs because of infection that was missed at surgery. Preoperative MR imaging can help to prevent recurrence. The purpose of the study was, in this article we study the various types of perianal fistulas with MR imaging and study the usefulness of MR imaging in delineating the primary tract and complications of perianal fistula.

Methods: We studied MRI images of 35 patients with different types of perianal fistulas. MR imaging were performed on 1.5-T magnet MR system (Siemens magneto Essenza). Imaging was performed with multiplanar T1-weighted, T2-weighted and PDFS sequences.

Results: Total 35 patients were studied, out of which 18 (51%) patients showed grade 1 (simple linear intersphincteric fistula), 5 (14%) showed grade 2 (intersphinc¬teric with abscess or secondary tract), 6 (21%) showed grade 3 (transsphincteric), 5 showed grade 5 (14%) (transsphincteric with abscess or secondary tract in ischiorectal or ischioanal fossa) and none (0%)showed  grade 5 (supralevator and translevator).

Conclusions: MR imaging provides precise location of the fistulous track, and its relationship to pelvic floor and the sphincter complex   and helps in the identifi¬cation of secondary tracks and abscesses.   



MRI, Perianal fistula, Intersphincteric, Transsphincteric

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Sainio P. Fistula-in-ano in a defined population: incidence and epidemiological aspects. Ann Chir Gynaecol. 1984;73(4):219-24.

Verma A, Vyas S, Patwari S, Verma M, Srivastava A, Shukla RC. Magnetic ResonanceFistulogram Demonstration of Urethrovesicovaginal Fistula in a Case of Müllerian Agenesis Due to Traumatic Urethral Coitus.Journal of Minimally Invasive Gynecology. 2012;19:259-61.

Goodsall DH, Miles WE. Diseases of the anus and rectum. London, England: Longmans, Green. 1900.

Beckingham IJ, Spencer JA, Ward J, Dyke GW, Adams C, Ambrose NS. Prospective evaluation of dynamic contrast enhanced magnetic resonance imaging in the evaluation of fistula in ano. Br J Surg. 1996;83(10):1396-8.

Buchanan G, Halligan S, Williams A. Effect of MRI on clinical outcome of recurrent fistula-in-ano. Lancet. 2002;360(9346):1661-2.

Seow-Choen, Phillips RK. Insights gained from the management of problematical anal fistulae at St. Mark’s Hospital, 1984-88. Br J Surg. 1991;78(5):539-41.

Kuijpers HC, Schulpen T. Fistulography for fistula-in-ano: is it useful? Dis Colon Rectum. 1985;28(2):103-4.

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

Spencer JA, Chapple K, Wilson D, Ward J, Windsor ACJ, Ambrose NS. Outcome after surgery forperianal fistula: predictive value of MR imaging.AJR Am J Roentgenol. 1998;171:403-6.

Halligan S, Stoker J. Imaging of fistula in ano. Radiology. 2006;239(1):18-33.

Guillaumin E, Jeffrey RB, Shea WJ, Asling CW, Goldberg HI. Perirectal inflammatory disease: CT findings. Radiology. 1986;161(1):153-7.

Yousem DM, Fishman EK, Jones B. Crohn disease: perirectal and perianal findings at CT. Radiology. 1988;167(2):331-4.

Law PJ, Bartram CI. Anal endosonography. tech¬nique and normal anatomy. Gastrointest Radiol. 1989;14(4):349-53.

Van Outryve M, Pelckmans P, Fierens H, Van Maercke Y. Transrectal ultrasonographic examina¬tion of the anal sphincter. Acta Gastroenterol Belg. 1994;57(1):26-7.

Van Outryve MJ, Pelckmans PA, Michielsen PP, Van Maercke YM. Value of transrectal ultrasonography in Crohn’s disease. Gastroenterology. 1991;101(5):1171-7.

Buchanan GN, Halligan S, Bartram CI, Williams AB, Tarroni D, Cohen CR. Clinical examination, endosonography, and MR imaging in preoperative assessment of fistula in ano: comparison with outcome-based reference standard. Radiology. 2004;233(3):674-81.

Bartram C, Buchanan G. Imaging anal fistula. Ra¬diol Clin North Am. 2003;41(2):443-57.

Halligan S, Bartram CI. MR imaging of fistula in ano: are endoanal coils the gold standard? AJR Am J Roentgenol. 1998;171(2):407-12.

Sahni VA, Ahmad R, Burling D. Which method is best for imaging of perianal fistula? Abdom Imaging. 2008;33(1):26-30.

Spencer JA, Ward J, Beckingham IJ, Adams C, Ambrose NS. Dynamic contrast-enhanced MR imaging of perianal fistulas. AJR Am J Roentgenol. 1996;167(3):735-41.