Swallowing a tiny imaging capsule aids in diagnosis of obscure gastrointestinal bleeding

The use of a small wireless capsule video device to detect bleeding in the small intestine is safe, well-tolerated, and more accurate than another common diagnostic approach according to a study presented at the 67th Annual Scientific Meeting of the American College of Gastroenterology.

“The investigation of obscure gastrointestinal bleeding is often difficult due to limitations of conventional endoscopic studies in the detection of disorders in the small intestine,” said Ramona M. Lim, M.D., of the University of Miami School of Medicine/Mount Sinai Medical Center in Miami, FL.

Patients with obscure GI bleeding experience bleeding of unknown origin that persists or recurs after a negative initial endoscopy (colonoscopy and/or upper GI endoscopy). For some of these patients the bleeding may be caused by lesions in the small intestine that would not be detected with colonoscopy or upper GI endoscopy.

In wireless capsule endoscopy, the patient swallows a tiny imaging capsule that incorporates a light source, video camera, battery, antenna, and radio transmitter. Images of the intestinal tract are transmitted twice each second by radio frequency to an array of sensors worn around the patient’s abdomen and the signals are digitally recorded on a device that is later downloaded. The patient swallows the capsule in the morning and wears the recording device for 8 hours. The capsule is eliminated and discarded. A gastroenterologist reviews the images.

Dr. Lim and her colleagues studied 20 patients with GI bleeding from an unidentified source.

Researchers evaluated these patients using the wireless capsule technology, then followed up using a technique known as push enteroscopy. In push enteroscopy, a four-foot long tube outfitted with a small video camera is inserted down the esophagus, through the stomach and into the first third of the small intestine. The researchers found that wireless capsule endoscopy identified potential sources of bleeding in 70 percent of the patients, compared to 45 percent with push enteroscopy.

While the Miami study revealed that this technology is more sensitive than push enteroscopy in detecting problems in the small intestine, it is not without drawbacks. With wireless capsule endoscopy a gastroenterologist cannot biopsy or treat bleeding in the small intestine. The use of this technology is not appropriate for patients with bowel obstructions.