
A narrowed sigmoid colon without haustration in a patient with extensive colitis for about 30 years.

The descending colon (D), narrowed and without haustration. In the oral part of the transverse colon (T) there are some haustration.

A narrowed rectum (R), sigmoid colon (S) and descending colon (D). The distal colon can becoome so narrowed after tens of years of colitis, that examination with a colonoscope is not possible. In these cases, profylactic colectomy is probably indicated, due to the risk of cancer after an ulcerative colitis of long duration.
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