Colonoscopy is the visual examination of the large intestine (colon) using a lighted, flexible video endoscope. The colon begins in the right-lower abdomen and looks like a big question mark as it moves up and around the abdomen, ending in the rectum. It is 5 to 6 feet long. The colon has a number of functions including withdrawing water from the liquid stool that enters it so that a formed stool is produced.

This test is ordered by your GI doctor to evaluate the upper portion of the gastrointestinal (GI) tract. The upper GI tract includes the esophagus, stomach and the first part of the small intestine called the duodenum. Your doctor will use a flexible, slender camera scope to evaluate this area. 

Capsule endoscopy is a procedure that uses a tiny wireless camera to take pictures of your digestive tract. A capsule endoscopy camera sits inside a vitamin-size capsule you swallow. As the capsule travels through your digestive tract, the camera takes thousands of pictures that are transmitted to a recorder you wear on a belt around your waist.

Endoscopic mucosal resection (EMR) is performed with an endoscope, which is a long, narrow tube equipped with a light and video camera. During EMR of the upper digestive tract, the doctor passes this tube (endoscope) through your mouth into your esophagus, stomach or upper part of the small intestine (duodenum). To reach the colon, the doctor guides a scope up through the anus. The doctor then inserts instruments through the endoscope to perform the procedure.