Guidelines for Imaging of Crohnʼs Perianal Fistulizing Disease

The development of a magnetic resonance imaging index for fistulising Crohn's disease

“…1 The original van Assche index consists of six anatomical and (weighted) inflammatory disease parameters including assessment of; the numbers of fistula tracts (0 -3), the location of fistulas (1 -3), extension of fistulas (1 or 2), hyperintensity on T2-weighted images (0, 4, or 8), presence of collections (defined as cavities >3 mm in diameter) (0 or 4) and rectal wall involvement (score 0 or 2). The total score ranges from 0 to 22; 2 Definitions were applied to modified index only; 3 Adapted from the St. Mark's Classification 23 in the modified index (the most dominant feature is assessed for both the original and modified indices); 4 For the modified index, all relevant findings are identified; the highest score is chosen; 5 For the modified index, extensions were also assessed and the most severe lesion was rated by comparing signal intensity with nearby, in-plane vessels in the modified index; images were fat saturated Table 2. Reliability* of the VAS, original and modified van Assche indices.…”

“…In clinical practice, pelvic magnetic resonance imaging (MRI) has an established role for the evaluation of patients with perianal fistulas and is used to make clinical decisions and assess changes in disease state. 3,4 While several scoring systems, such as the Fistula Drainage Assessment and the partially validated Perianal Disease Activity Index, have been used to quantify clinical parameters, far fewer have been developed for MRI and they also lack standardised definitions of descriptor items. 5 The most frequently used MRI index is the Van Assche index, originally developed to fulfill the need for an instrument that could measure response of perianal fistulising CD to medical therapy.…”

Before and after Anorectal Surgery: Which Information Is Needed from the Functional Laboratory

“…EUS is often done in patients with perianal manifestation of Crohn's disease. However, complex anal fistulas, especially with supralevatoric extension, can be difficult to detect [14]. In these cases, magnetic resonance imaging (MRI) should be performed.…”

Can MR enterography screen for perianal disease in pediatric inflammatory bowel disease?

“…1 CD has a known association with perianal fistulous disease, which may be the first presentation of CD or may develop later. [6][7][8] MRE and P-MRI are not routinely performed at the same time in children with IBD. In the largest pediatric cohort to date, perianal disease (PAD)-including skin tags and fissures-developed in 21% of patients during their disease course.…”

“…Pelvic MRI (P-MRI) optimized for the perianal region is recognized as the reference standard. [6][7][8] MRE and P-MRI are not routinely performed at the same time in children with IBD. This is due to issues of procedure length, which can occasionally result in diarrhea if enteral contrast reaches the distal colon, and patient compliance.…”