Inclusion Criteria:

• Male or nonpregnant, nonlactating females, 16 or 18 (site-specific) to 75 years of age at the time of the baseline CTE or MRE.
  • Note: the minimum age requirement of “16 to 75 years of age” or “18 to 75 years of age” is at the discretion of each investigative site (site-specific decision).
• An established diagnosis of CD.
• Documented symptomatic stricturing small bowel CD in reach of colonoscopy (i.e., a portion of the stricture is located within 15 cm of the ileocecal valve or ileocecal anastomosis).
• Anastomotic or naïve small bowel CD stricture(s) at the time of the baseline MRE, where:
  • Naïve small bowel stricture is defined by the combination of:
  • localized luminal narrowing (luminal diameter reduction of at least 50% relative to normal adjacent bowel loop); AND
  • bowel wall thickening (25% increase relative to adjacent nonaffected bowel); AND either:
  • prestricture dilation (luminal diameter greater than 3 cm);
  • inability to pass an adult or pediatric colonoscope through the narrowed area prior to dilation AND unequivocal proximal small bowel dilation (≥ 2.5 cm but may be less than 3 cm). Endoscopic diagnosis of stricture based on inability to pass the colonoscope through the narrowed area should be within 6 months of MRE.
  • An anastomotic stricture is defined the same as a naïve stricture, but at the site of prior intestinal resection with anastomosis.
• Clinical symptoms consistent with obstruction (e.g., bloating, abdominal distension, cramping, dietary restrictions, nausea/vomiting, abdominal pain, and/or postprandial abdominal pain) within 1 month of the baseline MRE.
• Ability of subject to participate fully in all aspects of this study.
• Written informed consent is obtained and documented.

Exclusion Criteria:

• Internal penetrating disease as shown by fistula, abscess, or inflammatory mass (phlegmon) at baseline. A blind-ending sinus tract is not excluded.
• Gastrointestinal malignancies.
• More than 2 distal ileal strictures at the time of baseline MRE (where 2 strictures within 3 cm are considered the same stricture; a long segment with multiple areas of narrowing or multiple strictures that have inflammation between them is counted as 1 stricture).
• A terminal ileal stricture in a subject with end ileostomy, where the stricture is confined within the subcutaneous tissues and does not extend intra-abdominally.
• A diverting loop ileostomy proximal to the dominant stricture.
• Total proctocolectomy with an ileoanal or Kock pouch.
• Stricturoplasty in the distal ileum.
• Contraindication to MRE or inability to undergo MRE (e.g., claustrophobia).

Eligibility last updated 6/14/23. Questions regarding updates should be directed to the study team contact.