Enteroscopy is the procedure of using an

endoscope An endoscope is an inspection instrument composed of image sensor, optical lens, light source and mechanical device, which is used to look deep into the body by way of openings such as the mouth or anus. A typical endoscope applies several modern ...

for the direct visualization of the

small bowel The small intestine or small bowel is an organ in the gastrointestinal tract where most of the absorption of nutrients from food takes place. It lies between the stomach and large intestine, and receives bile and pancreatic juice through the p ...

Etymologically Etymology ( ) is the study of the origin and evolution of words—including their constituent units of sound and meaning—across time. In the 21st century a subfield within linguistics, etymology has become a more rigorously scientific study. ...

, the word could potentially refer to any bowel endoscopy ('' entero-'' + '' -scopy''), but idiomatically it is conventionally restricted to small bowel endoscopy, in distinction from

colonoscopy Colonoscopy () or coloscopy () is a medical procedure involving the Endoscopy, endoscopic examination of the large bowel (colon) and the distal portion of the small bowel. This examination is performed using either a Charge-coupled device, CCD ...

, which is large bowel endoscopy. Various types of enteroscopy exist, as follows: * Video chip enteroscopy ** Double-balloon enteroscopy ** Single-balloon enteroscopy ** Spiral enteroscopy * Wireless endoscopy ** Capsule endoscopy As the small bowel can often be a source of pathology, endoscopy of the small bowel can be a useful diagnostic and therapeutic technique.

Esophagogastroduodenoscopy Esophagogastroduodenoscopy (EGD) or oesophagogastroduodenoscopy (OGD), also called by various other names, is a diagnostic endoscopic procedure that visualizes the upper part of the gastrointestinal tract down to the duodenum. It is considered ...

, also called upper endoscopy, gets as far as the first segment of the small bowel, the

duodenum The duodenum is the first section of the small intestine in most vertebrates, including mammals, reptiles, and birds. In mammals, it may be the principal site for iron absorption. The duodenum precedes the jejunum and ileum and is the shortest p ...

, but the next two, the

jejunum The jejunum is the second part of the small intestine in humans and most higher vertebrates, including mammals, reptiles, and birds. Its lining is specialized for the absorption by enterocytes of small nutrient molecules which have been pr ...

and

ileum The ileum () is the final section of the small intestine in most higher vertebrates, including mammals, reptiles, and birds. In fish, the divisions of the small intestine are not as clear and the terms posterior intestine or distal intestine may ...

, require other methods. Visualization of the small bowel has long posed a challenge to

gastroenterologists Gastroenterology (from the Greek gastḗr- "belly", -énteron "intestine", and -logía "study of") is the branch of medicine focused on the digestive system and its disorders. The digestive system consists of the gastrointestinal tract, sometime ...

, due to the physical difficulty of reaching more

distal Standard anatomical terms of location are used to describe unambiguously the anatomy of humans and other animals. The terms, typically derived from Latin or Greek roots, describe something in its standard anatomical position. This position provi ...

regions of the small bowel. With the advent of the newer forms of enteroscopy, such as the double-balloon type, visualizing the entire tract is finally a practical reality in at least some cases, although it is still technically demanding. Traditional gastroscopes can generally visualize the proximal and distal

in the hands of experienced endoscopists but are limited due to the length of the instrument. Pediatric colonoscopes or sometimes dedicated enteroscopes which are much longer than standard gastroscopes can visualize the proximal

. This technique is referred to as push enteroscopy. Due to the length of the small bowel, averaging 4–6 meters in the adult, push enteroscopy is still not effective to adequately visualize large portions of the small intestine. Wireless capsule endoscopy has proven to be the endoscopic investigation of choice for visualization of the entire small bowel. An 11 x 26 mm pill sized video camera is swallowed by the patient and approximately 8 hours of video is transmitted wirelessly to a receiver worn by the patient. The procedure is painless, well accepted by patients and offers a very high accuracy. It is limited by the inability to obtain biopsies, and is therefore considered a purely diagnostic tool. Newer techniques, including single and double-balloon endoscopy have been developed to overcome some of these issues, but are limited by the length of the procedure, and the need for deep sedation or general

anesthesia Anesthesia (American English) or anaesthesia (British English) is a state of controlled, temporary loss of sensation or awareness that is induced for medical or veterinary purposes. It may include some or all of analgesia (relief from or prev ...

. Spiral enteroscopy is a novel technique that utilizes an overtube with raised spirals affixed on the enteroscope that is rotated to advance the enteroscope deep into the small bowel. Each of these 3 enteroscopy platforms offers similar accuracy and effectiveness but do not have widespread availability.

References

{{Authority control Digestive system imaging Endoscopy