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. It helps your doctor check for:
Typically, pieces of tissue will be taken as samples to check for any abnormal cell changes.
Procedure: Before the procedure, your doctor will have you lie on your left side on an examination table. They’ll insert a thin, flexible tube called a sigmoidoscope into your anus. The tube has a light and a very small camera on the end so images can be transmitted onto a monitor for your doctor to see. The tube also inflates your colon with some air to make it easier to examine. You might be uncomfortable, but the procedure isn’t typically painful. People aren’t usually under sedation during a sigmoidoscopy, so your doctor might ask you to shift every so often to make it easier to move the scope. If your doctor sees any polyps or growths, they might remove them. If there are any abnormal areas in your colon, small pieces of tissue might be removed for further examination.