Wireless capsule endoscopy and double-balloon enteroscopy for the diagnosis of obscure gastrointestinal bleeding.

Standard endoscopic examination (upper gastrointestinal endoscopy and colonoscopy) fails to detect the cause of gastrointestinal hemorrhage in approximately 5% of patients. Before the availability of wireless capsule endoscopy and double-balloon enteroscopy, imaging modalities for the small intestine distal to the ligament of Treitz included barium contrast examination and/or enteroclysis, push, passive, or intraoperative enteroscopy, technetium 99m labeled sulfur colloid scanning, angiography, and computed tomography, although the diagnostic yield of all of these imaging modalities was low. In 2001, wireless capsule endoscopy became available for the evaluation of patients with probable small intestinal hemorrhage. Advantages of wireless capsule endoscopy include that the procedure is noninvasive, requires no sedation, and does not expose the patient to ionizing radiation. In patients with obscure gastrointestinal hemorrhage, studies have demonstrated an additional 25 to 50% diagnostic yield using wireless capsule endoscopy when compared to other diagnostic modalities. The major limitations of capsule endoscopy were its inability to obtain a biopsy, precisely localize a lesion, or perform therapeutic endoscopy. In 2001, the double-balloon enteroscope was introduced. This new endoscopic technique provides the gastroenterologist with an opportunity for further evaluation and treatment of abnormalities detected on wireless capsule endoscopy or other small intestinal imaging studies.