DIGESTIVE DISEASE CENTER | Gastroenterology home | Surgery home

Patient care — diagnostic tools, tests, procedures

Small bowel endoscopy: Endoscopy is a minimally invasive diagnostic medical procedure that is used to assess the interior surfaces of an organ by inserting a tube into the body. The instrument may have a rigid or flexible tube and not only provide an image for visual inspection and photography, but also enable taking biopsies and retrieval of foreign objects. Endoscopy is the vehicle for minimally invasive surgery.

Capsule endoscopy: In 2000, a group of doctors from England reported the use of a new instrument for determining the causes of small bowel bleeding. The device, the endoscopic capsule, is 1-1/8 in long and 3/8 in width, the size of a large pill, and held a battery with a 6 hour lifespan, a strong light source, a camera and a small transmitter. Once swallowed, the capsule begins transmitting images of the inside of the esophagus, stomach and small bowel to a receiver worn by the patient. After 6 hours the patient returns the receiver to the doctor who loads the information into a computer and then can review in detail the 6 hours of pictures of the capsule passing through the intestine looking for abnormalities that are possible sources of bleeding. The patient passes the capsule through the colon and it is eliminated in the stool and discarded. The capsule is safe, easy to take and has had only rare reported side effects. However, the capsule can get stuck in the small intestine if there has been prior abdominal surgery causing scarring or due to any other condition that causes narrowing of the small intestine. If the capsule becomes stuck, surgical removal is necessary.

How effective is capsule endoscopy in detecting the source of small intestine bleeding?

illustration, photo

In an initial study, investigators showed that the capsule was better than routine endoscopy or enteroscopy at locating small beads that had been implanted into an animal's intestine. Other studies have shown the capsule is more effective than small bowel x-rays at finding the cause of bleeding. In 2001, the first human studies reported that capsule endoscopy not only found all of the bleeding sources seen using standard endoscopy, but also an additional bleeding cause in 56% of patients for whom traditional endoscopy had not been successful. In 2002 and 2003, numerous scientific presentations showed the use of capsule endoscopy in obscure GI bleeding, as a screening tool for patients with genetic predisposition for small bowel cancer, for small bowel Crohn's disease and for small bowel malabsorption. The capsule endoscope is now the new first line test for evaluation of small bowel GI bleeding in many medical centers.

However, capsule endoscopy technology is not perfect. Although it is better than other available techniques to detect sources of small bowel bleeding, capsule endoscopy does not detect all sources of small bowel bleeding. Like X-rays, the capsule is purely diagnostic and cannot be used to take biopsies, apply therapy or mark abnormalities for surgery. Moreover, the capsule cannot be controlled once it has been ingested, so that once it has passed a suspicious abnormality, its progress cannot be slowed to better visualize the area.

Despite these limitations, it is increasingly clear that capsule endoscopy has a place in the evaluation of small bowel bleeding, and that it will replace some standard diagnostic techniques currently in use. The technology is not yet at a point where it can adequately visualize enough of the colon wall. However, one day the use of the capsule endoscopy may be extended to routine colorectal cancer screening.

Return to diagnostic tools, tests page