MRI
Axial T1 C+ fat sat
Axial T1
Axial T2 fat sat
Axial T2
Coronal T1 C+
A long thin walled fistulous tract is seen on the right side of the perianal region. It pierces the internal sphincter at 6 o`clock and passes posteriorly up close to the intersphincteric plane until it reaches the internal opening at 7 o`clock. No related abscesses, side branches or ramifications. The tract showed mild restriction on diffusion-weighted imaging (not shown here). Unremarkable appearance of the rest of the pelvic organs. No free pelvic fluid.