To focus on STRIDENT intervention studies as this study population is heterogenous

Two thirds of patients with Crohn's disease require intestinal surgery at some time in their life. Intestinal strictures, that is narrowing of the bowel due to inflammation and scarring, are the most common reason for surgery. Despite the high frequency, associated disability, and cost there are no are no treatment strategies that aim to improve the outcome of this disease complication. The STRIDENT (stricture definition and treatment) studies aim to determine biochemical and imaging features associated with the development of strictures and in related STRIDENT studies develop strategies for treatment.

Patients with asymptomatic Crohn's disease strictures will be followed prospectively for 12 months using imaging (including MRI/intestinal ultrasound) and biochemical analyses (including CRP/calprotectin). Patient's with symptomatic or asymptomatic ulcerative colitis related strictures will be followed similarly. Risk factors for progression of strictures and development of symptoms will be identified.

Inclusion Criteria:

• Inflammatory bowel disease patients with intestinal stricture(s) identified on CT, MRI or endoscopy but without associated symptoms

Exclusion Criteria:

• Low rectal or anal strictures
• Evidence of dysplasia or malignancy from stricture biopsies or adjacent mucosal biopsies
• Patients for whom endoscopy is not suitable due to co-morbidities or clinical state
• Inability to give informed consent
• Suspected perforation of the gastrointestinal tract
• Inability to undergo MRI small bowel due to a contraindication.

Patients with inflammatory bowel disease (Crohn's Disease or Ulcerative Colitis) without symptoms who are incidentally found to have a stricture on CT, MRI or endoscopy.