Image 1.

Barium Enema slide of  a female patient with long standing Crohn’s Disease.
The descending colon has a short segment which shows asymmetrical puckering (or thumbprinting) of the mucosal surface suggesting an extrinsic invading  lesion.   There are several strictures visible in the terminal ileum and small bowel (one lies next to the large bowel abnormality) and some of the barium has refluxed into these areas.  Conclusion:   Focal abnormality and small bowel inflammation typical of Crohn’s disease

I want to point out that doing a barium enema, is the wrong test. This example above, “got lucky”, and had barium reflux into the terminal ileum, AND manage to flow backwards through some tight strictures of small bowel. Usually that wouldn’t happen. A small bowel follow-through with swallowed barium, is a better test.

I have no idea what I’m looking at.

Crohn’s Disease: Radiological Signs

In Crohn’s disease the inflammation affects the full thickness of the bowel known as transmural inflammation which can lead to sinus tracts developing, thickening and strictures of the bowel wall (as seen in image 1). The ‘thumbprinting’ or thumbprint shaped projections demonstrated in Image 1 are a classic sign of thickening of the large bowel or colon. The haustra have become thickened at regular intervals and appear like thumb prints. This is usually a sign of oedema related to the inflammatory process of the disease. A non-diseased, or normal bowel, is characterized by small pouches that run along the colon called haustra which give the intestine it’s segmented, ribbed appearance. Crohn’s disease is characterized by apthous ulcers (ulceration) and inflammation that can occur throughout the whole of the gastrointestinal tract. These ulcers can enlarge and merge to form patchy clusters, and if deep enough they can lead to fistulas. A fistula, in this case, is an abnormal passage between the bowel and another structure. The ulcers can form a criss-crossing pattern separating islands of mucosa giving a cobblestone appearance, as clearly shown in Image 2 below.

Image 2

A Small Bowel Enema  showing extensive jejunal disease characterized by  loss of distensibility,  (the capability of being stretched or distended), thickening of the small-bowel wall and gross disruption of the circular haustral fold pattern, which is largely replaced by a marked cobblestone effect.  Conclusion:  Crohn’s Disease of the jejunum

Hey, they’ve still used a small bowel enema, why’s that?

No, this examination is sometimes called a small bowel enema or Enteroclysis, but that’s confusing because the barium is swallowed and a tube is passed into the small bowel and the images taken. This is what I was talking about when I mentioned a ‘small bowel follow through’.

Okay, but I still have no idea what I’m looking at!

Image 3

‘ Comb Sign’ in Crohn’s disease.

Post contrast coronal image showing a long segment of  thickening of the ileum  with prominence of mesentric vasculature. Distended mesenteric vessels clearly stand out and extend to inflamed segments of small bowel like the teeth of a comb, hence the name.   The vessels stand out due to the inflammation and also to the presence of fibrofatty proliferation around them. Image also shows slight ascites.

Knock Knock, Who’s there? Comb, Comb Who? Comb down and I’ll tell you!

Crohn’s Disease

Crohn’s disease is one of the two principal inflammatory bowel diseases (IBD), the other being Ulcerative Colitis.  Inflammatory bowel disease is a term that covers conditions that are characterized by inflammation and ulceration of the gastrointestinal tract. Crohn’s disease is similar to Ulcerative Colitis in that it is a chronic inflammatory disease affecting the gastrointestinal tract. In Crohn’s disease the inflammation can occur anywhere along the whole of the digestive tract, from the mouth to the anus. In Ulcerative Colitis the inflammation typically involves only the colon (or large intestine) and occasionally, the rectum. Crohn’s disease is known as a chronic relapsing illness; chronic meaning that it is persistent or ongoing and relapsing meaning the disease process has intermittent periods of time whereby it is either active (a flare up) or inactive (in remission).

Sources

1. http://www.radiology.co.uk/cases/case-42-diagnosis
2. Vallance, R. An Atlas of Diagnostic Radiology in Gastroenterology. Oxford: Blackwell Science, 1998.(http://www.gastrohep.com/images/image.asp?id=12)
3. http://radiopaedia.org/cases/crohns-disease-11