Background: Perianal fistula is a commonly encountered condition in routine surgical practice. Accurate presurgical mapping of these tracts is vital to prevent recurrence. We have assessed the effectiveness of percutaneous instillation of aqueous jelly prior to magnetic resonance (MR) fistulography.
Aims and objectives: To study the role of percutaneous instillation of aqueous jelly in fistulous tracts prior to MR fistulography.
Materials and methods: All patients with active discharge, referred for MR fistulography between January 2014 and April 2016, were included in this study. Approximately 3-5 ml of sterile aqueous jelly was percutaneously instilled into the external openings prior to MR fistulography. Post MR fistulography, patients were monitored till surgery for pain, fever, or bleeding. The type of fistulae, location of internal openings, lateral ramifications, and presence of abscess were compared with per operative findings for diagnostic accuracy.
Results: Sixty-four patients enrolled in our study had undergone preoperative MR fistulography with aqueous jelly instillation. MR fistulography revealed a total of 77 tracts and showed a sensitivity and specificity of 100% in delineation of type of tract. Forty-nine internal openings were identified with 94.2% sensitivity, 100% specificity, and 95.3% accuracy. 90.5% sensitivity, 100% specificity, and accuracy of 97% were observed in delineation of lateral ramifications. None of the patients reported pain, fever, or bleeding post procedure till surgery.
Conclusion: Percutaneous instillation of aqueous jelly prior to MR fistulography is a safe, cost effective, and accurate technique to provide a comprehensive delineation of the complex anatomy of perianal fistulae.
Keywords: Aqueous jelly; magnetic resonance imaging; perianal fistula.