Crohn Disease



Crohn Disease


R. Brooke Jeffrey, MD





Key Facts


Terminology



  • Terminal ileitis, regional enteritis, ileocolitis


  • Chronic, recurrent, segmental, granulomatous inflammatory bowel disease


Imaging



  • Best diagnostic clue: Segmental areas of ileo-colonic ulceration and wall thickening on barium study


  • Early changes seen in barium studies



    • “Cobblestoning”: Combination of longitudinal and transverse ulcers


    • Deep fissuring ulcers


    • Mural thickening: Transmural inflammation, fibrosis


  • Late changes seen in barium studies



    • Skip lesions: Segmental/normal intervening areas


    • “String” sign: Luminal narrowing + ileal stricture


    • Sinus tracts, fissures, fistulas: Hallmarks of Crohn


  • Best imaging tools



    • Barium enema, enteroclysis


    • MDCT ± contrast


    • MR for perianal and rectal Crohn disease


Pathology



  • Possible factors include genetics, environment, infection, psychology; exact etiology unknown


Clinical Issues



  • Complications: Fistula, sinus, toxic megacolon, obstruction, perforation, malignancy


Diagnostic Checklist



  • Consider associated findings (cholangitis, arthritis)


  • CECT: SB wall thickening, mesenteric fat proliferation, hyperemia very suggestive of Crohn






(Left) Coronal volume-rendered CECT enterography in a 27-year-old man presenting with RLQ pain demonstrates marked mucosal hyperemia image and asymmetric mural thickening image of the terminal ileum. (Right) Coronal CT enterography curved planar reconstruction through the diseased segment of the terminal ileum in the same patient reveals skip areas of involvement with 2 areas of stricture formation image.






(Left) Axial CECT in a 48-year-old woman presenting with recent weight loss and diarrhea shows segmental small bowel wall thickening characterized by excessive submucosal fat deposition image, indicative of chronic inflammation. The nonepithelialized fistulas image extend from 1 bowel segment to the others. (Right) Coronal CECT in the same patient again demonstrates the extension of the nonepithelialized fistulas image between the bowel segments.



TERMINOLOGY


Synonyms



  • Terminal ileitis, regional enteritis, ileocolitis


Definitions



  • Chronic, recurrent, segmental, granulomatous inflammatory bowel disease


IMAGING


General Features



  • Best diagnostic clue



    • Segmental areas of ileo-colonic ulceration and wall thickening on barium study


  • Location



    • Anywhere along gastrointestinal (GI) tract, from mouth to anus



      • Most common: Terminal ileum (TI) and proximal colon


    • Distribution



      • TI (95%), colon (22-55%)


      • Rectum (14-50%)


  • Morphology



    • Skip lesions (segmental or discontinuous)


    • Transmural, granulomas (noncaseating type)


    • “Cobblestone” mucosa, fissures, and fistulas


Fluoroscopic Findings

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Jun 13, 2016 | Posted by in GASTROINTESTINAL IMAGING | Comments Off on Crohn Disease

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