Magnetic resonance imaging features and factors associated with complex anal fistulas according to the Garg classification
Main Article Content
Abstract
A cross-sectional descriptive study was conducted on 240 patients with anal fistula who underwent preoperative magnetic resonance imaging (MRI) at Viet Duc University Hospital from June 2024 to March 2026, aiming to describe MRI features and identify factors associated with complex anal fistulas according to the Garg classification. Anal fistulas were categorized into two groups: simple (Garg I–II) and complex (Garg III–V). MRI features including internal opening, secondary tracts, abscesses, horseshoe fistulas, and the number of external openings were analyzed using univariate and multivariate logistic regression. The mean age was 40.10 ± 13.78 years old, predominantly males at 89.2%. The prevalence of complex fistulas was 47.1%. MRI identified the internal opening in more than 96% of cases in both groups. Secondary tracts, abscesses, horseshoe fistulas, and ≥ 2 external openings were significantly more frequent in the complex fistula group (p < 0.05). Multivariate analysis demonstrated that secondary tracts (adjusted OR = 5.03; p < 0.001) and abscesses (adjusted OR = 3.16; p < 0.001) were independently associated with complex anal fistulas. MRI has high value in the classification and treatment planning of anal fistulas.
Article Details
Keywords
Anal fistula, magnetic resonance imaging, Garg classification, complex fistula, secondary tract, abscess
References
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