1. Figure 5 Complex perianal fistula
Figure 5 | Complex perianal fistula. a | An axial T2-weighted image with fat saturation, showing a left trans-sphincteric fistula with a marked hyperintensity component on T2 sequence. The internal opening is located on the posterior aspect of the anal canal (arrowhead). There is an associated abscess in the left ischioanal fossa (long arrow). A second abscess in the right ischioanal fosa can be noted (short arrow) associated with another fistula tract (not seen). b | Image of the same fistula corresponds to an axial contrast-enhanced T1-weighted image showing lack of enhancement on the central part of the abscesses confirming the presence of pus (arrows). c | Coronal T2 fat-saturated image that depicts a left ischioanal roof extension. The rectal wall (not seen) was normal. The total van Assche MRI activity score was 18.
Panés, J. & Rimola, J. (2017) Perianal fistulizing Crohn’s disease: pathogenesis, diagnosis and therapy
Nat. Rev. Gastroenterol. Hepatol. doi: /nrgastro