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Updated: Jul 15, 2026
08:39
Murine Colitis Modeling using Dextran Sulfate Sodium (DSS)
Published on: January 19, 2010
Summary
Dilation of the transverse colon in toxic megacolon is not a specific feature. Gas distribution in the colon is mainly influenced by gravity and patient positioning, not solely by the disease.
Area of Science:
- Gastroenterology
- Radiology
- Colorectal Surgery
Background:
- Toxic megacolon is a severe complication of ulcerative colitis.
- The role of colonic dilation in toxic megacolon pathophysiology requires clarification.
Purpose of the Study:
- To investigate if transverse colon dilation is a specific pathophysiologic feature of toxic megacolon.
- To understand the influence of patient positioning on colonic gas distribution in toxic megacolon.
Main Methods:
- Plain abdominal films were obtained in supine and prone positions for 6 patients with ulcerative colitis and toxic megacolon.
- Pathological examination of colonic tissue was performed for 5 patients.
Main Results:
- Gas redistribution occurred in all patients when moving from supine to prone position, shifting from the transverse to the descending colon.
- Pathological findings did not show more severe involvement of the transverse colon compared to other segments.
Conclusions:
- Transverse colon dilation is not a specific pathophysiologic feature of toxic megacolon.
- Colonic gas distribution in toxic megacolon is primarily influenced by gravity and anatomical position.
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