Large amount of faecal material in the rectum and distal sigmoid, with the remainder of the colon back to the hepatic flexure demonstrating gaseous distension and measuring up to 8 cm in diameter. Further faecal material is seen in the cecum and ascending colon. No distension of the small bowel, likely reflecting a competent ileocecal valve.
Small amount of free fluid. No organised collection. No extraluminal gas or pneumatosis.
Circumferential wall thickening of the colon is demonstrated from the splenic flexure to the rectum. Engorgement of the paracolic veins and engorgement of the inferior mesenteric vein. Reactive prominence of the draining mesenteric nodes. An indwelling catheter balloon is present in the urinary bladder.
Conclusion:
Long segment colitis from the rectum to the splenic flexure, with marked gaseous distension. The possibilities include infective and inflammatory colitides. In that context the dilated appearance may be in keeping with toxic megacolon.
Another possibility is stercoral colitis, with a migrating faecal bolus currently in the rectum.