Role of MRI and Conventional X-Ray Fistulogram in Evaluation of Fistula in Ano (Code-T0076)

Introduction: Fistula in ano is a challenging anorectal condition characterized by an abnormal communication between the anal canal and perianal skin. Accurate evaluation of the fistula’s course and complexity is crucial for determining the appropriate surgical treatment. Magnetic Resonance Imaging (MRI) and conventional X-ray fistulogram are the most commonly used imaging techniques for assessing fistula in ano, with each offering unique advantages in terms of anatomical detail and accuracy.

Aims and Objective:

Primery Objective:

• Evaluation of MRI fistulogram finding with intra operative finding.
• Evaluation of X-RAY fistulogram finding with intra operative finding.
• Evaluation of MRI fistulogram finding with X-RAY fistulogram finding.

Secondary Objective:

(1)Incidence of fistula in Ano

(2) Type of fistula in Ano

Methods: This prospective study included 120 patients diagnosed with fistula in ano, who were examined over a 10-month period. All participants underwent both MRI and conventional X-ray fistulogram. MRI was performed using a 1.5T scanner, with contrast-enhanced imaging to assess the fistula’s tract, relationship to the anal sphincters, and any associated abscesses. Conventional X-ray fistulogram was conducted by injecting contrast material into the fistula and evaluating the tract’s course. Results from both imaging modalities were compared for sensitivity, accuracy, and their ability to visualize fistula complexity.

Results: MRI demonstrated superior sensitivity (94%) and accuracy (91%) in comparison to X-ray fistulogram (sensitivity 78%, accuracy 75%). MRI provided better delineation of complex fistulas, including branching tracts and involvement of the anal sphincters, while X-ray fistulogram was limited to identifying the primary fistula tract.

Conclusion: MRI is the preferred imaging modality for evaluating fistula in ano, particularly in complex cases, due to its higher sensitivity and ability to visualize the fistula in detail. Conventional X-ray fistulogram remains useful for assessing the primary fistula tract but has limited value in complex anatomical cases.

Keywords: Fistula in Ano, MRI, X-ray Fistulogram, Anorectal Imaging, Diagnostic Accuracy, Surgical Planning.