From Capsule Endoscopy to Balloon-Assisted Deep Enteroscopy: Exploring Small-Bowel Endoscopic Imaging

In the past 15 years, the use of endoscopic evaluations in patients with obscure gastrointestinal bleeding has become more common. Indications for further endoscopic interventions include iron deficiency anemia, suspicion of Crohn's disease or small-bowel tumors, assessment of celiac disease or of ulcers induced by nonsteroidal anti-inflammatory drugs, and screening for familial adenomatous polyposis. Often, capsule endoscopy is performed in concert with other endoscopic studies and can guide decisions regarding whether enteroscopy should be carried out in an anterograde or a retrograde approach. Retrograde endoscopy is beneficial in dealing with disease of the more distal small bowel. Multiple studies have examined the diagnostic yield of balloon-assisted deep enteroscopy and have estimated a diagnostic yield of 40% to 80%. Some of the studies have found that diagnostic yields are higher when capsule endoscopy is performed before balloon-assisted deep enteroscopy in a search for small-bowel bleeds. Each of these procedures has a role when performed alone; however, research suggests that they are especially effective as complementary techniques and together can provide better-directed therapy. Both procedures are relatively safe, with high diagnostic and therapeutic yields that allow evaluation of the small bowel. Because both interventions are relatively new to the world of gastroenterology, much research remains to be done regarding their overall efficacy, cost, and safety, as well as further indications for their use in the detection and treatment of diseases of the small bowel.