Your colon helps your body absorb water and nutrients from the food you eat. It’s also where your stool is formed. The last third of your descending colon is called the sigmoid colon. It’s connected to your anus by your rectum.
A colonoscopy helps doctors examine the entire colon. But sometimes only the sigmoid colon warrants close inspection. That’s when a doctor will recommend a sigmoidoscopy.
A sigmoidoscopy, also called a flexible sigmoidoscopy, is a procedure that lets your doctor look inside your sigmoid colon by using a flexible tube with a light on it.