CT confirms the findings of a distal large bowel obstruction. Whirlpooling of mesentery of the sigmoid colon with a clear transition zone is identified in the rectosigmoid. Proximal to it there is coffee bean like distension of the large bowel, accumulation of feces in small bowel, all in keeping with an ongoing large bowel obstruction. There is no features of bowel ischaemia. Mesenteric vessels are patent. No free intraperitoneal air.