The wireless capsule: new light in the darkness

The development of wireless capsule endoscopy offers the potential to examine the whole small intestine, with its 5-meter length, and has the advantage of being painless. Using a miniature CMOS camera and a short focal length lens, images are obtained, as the optical window of the capsule sweeps past the gut wall, without requiring air inflation of the gut lumen. The capsule endoscope is propelled by peristalsis through the gastrointestinal tract. The video images are transmitted using radiotelemetry to an array of aerials attached to the body which allows image capture. The images are stored on a small portable recorder carried on a belt and subsequently downloaded for analysis. The system allows more than 7 h of continuous recording of images of the gastrointestinal tract. The patients are free to continue their daily routine during the examination. The capsule endoscope has performed well in trials in patients with difficult gastrointestinal bleeding and in comparative studies with push enteroscopy. It has received both a CE mark and FDA approval for use in patients. It has been used to date in about 4,000 patients. The current clinical data are reviewed.