Diverticulitis of the Sigmoid Colon with Extraluminal Air on CT Scan

Findings
There are diverticula and thickening of the walls of the sigmoid colon with an adjacent extraluminal air pocket suggestive of local perforation and/or abscess formation.

Discussion
CT stages diverticulitis from Stage 0 through Stage IV depending on surrounding involvement and severity. Stage 0 shows only minor local colonic wall involvement and may be treated conservatively with antibiotics. The other stages usually necessitate surgical intervention. Stages I and II show contiguous spread of inflammation outside of the colon. Stages III and IV show peritoneal involvement with distant abscesses, ascites, through to frank peritonitis.


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