Visualization of the small bowel has posed a challenge to gastroenterologists due to the difficulty of physically reaching the small bowel anatomically. As the small bowel can be a source of pathology, endoscopy of the small bowel can be a useful diagnostic technique.
Traditional gastroscopes can visualize the proximal and sometimes distal duodenum. Longer gastroscopes or sometimes colonoscopes used for upper endoscopy can visualize the proximal jejunum. This technique is referred to as push endoscopy.
Wireless capsule endoscopy has proven to be the endoscopic investigation of choice for visualization of the entire small bowel, but is limited by intermittency of images, inability to obtain biopsies, and by cost.
Newer techniques, including double-balloon endoscopy are being developed to overcome some of these issues, but are limited by the length of the procedure, and the need for anesthesia.