Comparison of MR and fluoroscopic mucous fistulography in the pre-operative evaluation of infants with anorectal malformation: a pilot study.

Background: Anorectal malformations are often associated with rectal pouch fistulas. Surgical correction requires accurate evaluation of the presence and position of such fistulas. Fluoroscopy is currently the chosen modality for the detection of fistulas. The role of MRI is unexplored.
Objective: To compare the diagnostic accuracy of MR versus fluoroscopic fistulography in the pre-operative evaluation of infants with anorectal malformation.
Materials and Methods: We conducted a pilot study of infants requiring defunctioning colostomy for initial management of anorectal malformation. Dynamic sagittal steady-state free-precession MRI of the pelvis was acquired during introduction of saline into the mucous fistulas. Findings were compared among MR fistulography, fluoroscopic fistulography and intraoperative inspection.
Results: Eight children were included. Median age at fistulography was 15 weeks, inter-quartile range 13-20 weeks; all were boys. There was full agreement among MR fistulography, fluoroscopic fistulography and surgical findings.
Conclusion: The pilot data suggest that MR fistulography is promising in the pre-operative evaluation of children with anorectal malformation.