The role of preoperative MRI in the diagnosis of anal fistulas
Main Article Content
Abstract
The study aimed to evaluate the role of magnetic resonance imaging (MRI) in the diagnosis of anal fistula. Subjects included 57 patients with anal fistula undergoing MRI and surgery; there were 55 men and 2 women (27.5:1) and the average age was 40.2 ± 12.2 years old. There were 57 major fistulas found intraoperatively. The level of good and very good agreement between MRI and surgery in classification of primary fistulas, detection of abscess and accessory fistulas with Kappa is 0.607 (0.52; 0.695), 0.782 (0.648; 0.916) and 0.82 (0.75;0.89), respectively. The sensitivity and specificity of MRI in detecting internal openings were 85% and 66.7%, in detecting abscesses were 84.6% and 100%. Both the T2W and post-contrast T1 TSE-Dixon sequences have high sensitivity and specificity in detecting internal openings, abscesses, and accessory fistulas. Thus, MRI has excellent soft tissue resolution to map the perianal anatomy, primary and secondary fistulas with abscesses involving the sphincter complex, helping surgeons make informed preoperative decisions.
Keywords: Anal fistula, MRI, classification of fistulas.
Article Details
Keywords
Anal fistula, MRI, classification of fistulas.
References
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