TWO CASES OF RETROPERITONEAL PERFORATION OF A DIVERTICULUM OF THE COLON-USEFULNESS OF PLAIN ABDOMINAL X-RAY AND CT-

[Case 1] A 72-year-old man visited anather clinic because of a left abdominal pain. On the following day, he was admitted to the hospital as an emergency patient in a shock state. Muscular defence was noted inthe abdominal resion, and abdominal X-ray revealed multiple macular bubbles in the aplenic flexure. CT showed retroperitoneal emphysema, and an emergency surgery was performed with a diagnosis of perforation of the colon. During surgery, perforation of a diverticulum was found in the splenic flexure, forming an abscess in the retroperitoneum. [Case 2] An 87-year-old woman was seen at the hospital because of a hypogastlargia. Abdominal X-ray and CT revealed a similar picture of retroperitoneal emphysema as shown in case 1, allowing a diagnosis of retroperitoneal perforation of the colon to be made. Perforation of a diverticulum of the descending colon was ascertained during surgery. Perforation of colon diverticula into the retroperitoneal space is thought to be relatively rare. However, its characteristic features on plain X-ray and CT are extemely usefulfor making the diagnosis and should always be borne in mind.