Capsule endoscopy allows the physician to examine the lining of the small intestine. The patient swallows a capsule the size of a large vitamin that contains a mini-camera and a light source. The capsule passes naturally through the digestive system while the camera takes pictures of the intestine. These images are transmitted to small sensors, which are placed on the abdomen. A receiver the size of a Walkman, which is worn around the waist, will store the images. Eight hours after ingesting the capsule, the test is finished and the receiver can be returned to the physician for processing.

You may already be familiar with other endoscopic procedures:

• Upper endoscopy (a procedure where you have to swallow a long flexible tube called an endoscope) is used to examine your esophagus, stomach and duodenum. The lower end of the intestine, the so-called large intestine or colon, can be looked at with similar tubes and examined for polyps, cancers and other abnormalities. While both upper endoscopy and colonoscopy are usually performed under conscious sedation (meaning that you receive medication to make you sleepy and comfortable during the procedure), capsule endoscopy just requires that you come to the physician's office to swallow the capsule and have sensors placed on your abdomen. You are then free to leave and go about most of your daily activities while the capsule passes through the digestive system. You will not need to retrieve the capsule. Once the images have been transmitted and the battery dies, the capsule has no value and can pass spontaneously in stool. Capsule endoscopy cannot replace the other endoscopic techniques but is particularly helpful to evaluate the small intestine for abnormalities such as bleeding.