Marked large bowel dilatation with caecum measuring up to 8.6 cm. Transition to collapsed bowel at the proximal sigmoid colon where there is a 3.0 cm stenosing lesion. Background of uncomplicated colonic diverticular disease. Hyperdense colonic contents, has the patient had recent enteric contrast? Pericolonic fat stranding and fluid around the ascending colon and caecum. No free gas. No enlarged lymph nodes.