Small-bowel endoscopy

Congratulations on the 50th anniversary of Endoscopy! We are honored to write an editorial on a landmark paper on small-bowel endoscopy. It is already nearly 50 years since “Endoscopy of the whole small intestine” was first described in Endoscopy by Deyhle et al. [1]. After successful total colonoscopy in 1969, it did not take too many years to achieve the total endoscopic inspection of the small intestine. Hideo Hiratsuka first accomplished this on March 29th in 1971 using the “ropeway” method [2]. Deyhle et al. also used a similar method to examine the whole of the small intestine in two patients with gastrointestinal blood loss of undetermined origin [1]. However, despite successful endoscopic investigation of the small bowel, these methods were not widely adopted because they were uncomfortable for the patient, complicated, and very time-consuming. Indeed, the guide-string for a subsequent enteroscopy could take several days to pass from mouth to rectum. Additionally, stretching of the string could damage the small-bowel mucosa and cause tremendous pain and discomfort that mandated the use of general anesthesia. Therefore “push enteroscopy” remained the standard enteroscopic procedure for about 30 years. However, push enteroscopy was incomplete, with a large area of the small intestine beyond the most proximal part still essentially uninvestigated.

This situation was changed by the development of both capsule endoscopy and double-balloon enteroscopy (DBE). Capsule endoscopy ([Fig. 1]) enabled total inspection throughout the small intestine, without any discomfort to patients, in a physiological setting. DBE, developed by one of the present authors, enabled detailed examination with biopsy and endoscopic therapy in the entire length of the small intestine ([Fig. 2]) [3]. These two methods are complementary and revolutionized the management of diseases of the small intestine. Soon after the development of DBE, single-balloon enteroscopy (SBE) and spiral enteroscopy were also invented. Together, the techniques of using an overtube to perform deep enteroscopy were termed “balloon-assisted enteroscopy” or “device-assisted enteroscopy.”

Fig. 1 State-of-the-art small-bowel endoscopic techniques: capsule endoscopy is less invasive than other techniques for examining the small intestine, but only allows image analysis of the mucosa of the gastrointestinal tract. (Illustration: Michal Rössler.)

Fig. 2 State-of-the-art small-bowel endoscopic techniques: double-balloon enteroscopy (DBE) is invasive but allows therapeutic interventions. a The DBE device. b The balloon of the overtube is inflated and anchors the bowel. The scope is advanced. c Then the balloon of the scope is inflated, anchoring itself to the bowel. d The overtube balloon is deflated and the overtube is pushed towards the tip of the scope. e, f Both balloons are inflated and the scope and balloon are pulled back, pleating the small bowel over the endoscope. g While the balloon of the overtube stays inflated, keeping the pulled-back small intestine in place, the scope, with its balloon deflated, is now advanced deep into the bowel again. These steps are then repeated until either the entire small bowel has been visualized or a point of maximum insertion has been reached. (Illustration: Michal Rössler.)

Balloon-assisted enteroscopy features not only deep intubation of the small intestine, but also improved control of the endoscope tip, even in the distal small intestine [4]. The DBE balloons can gently hold the wall of the small intestine, allowing arrangement of the intestinal shape to improve endoscopic insertion and control. Soon after the clinical usefulness of DBE was demonstrated in Japan, its diagnostic and therapeutic impact was also proven in Europe [5]. Peutz – Jeghers syndrome and small-intestinal vascular lesions and benign strictures are typical examples of small-bowel diseases whose management was revolutionized by DBE [4]. Importantly, endoscopic management is now available for problems that previously mandated surgery in those diseases, such as polyp resection, hemostasis, and closure of fistulas.

The usefulness of DBE is not limited to patients with normal small-intestine anatomy. Indeed, DBE is now being used routinely to investigate the upper and middle GI tract in patients with surgically altered upper GI anatomy, such as Roux-en Y anastomosis, gastric bypass surgeries resulting in hepaticojejunostomy. With the advent of DBE, reaching the hepaticojejunostomy became a routine procedure for the first time, allowing endoscopic access and biliary cannulation [6]. Combined with a short double-balloon endoscope having a working length of 155 cm and a 3.2-mm accessory channel (EI-580BT; Fujifilm, Tokyo, Japan), standard accessory devices developed for ERCP allow performance of most endoscopic procedures of the biliary system.

The small intestine is arguably the key organ of the GI tract. It is of course vital for digestion and absorption. It is also known to be important as an endocrine and immunological organ. Besides its part in intestinal disease it also has an important role in metabolic and allergy-related pathology and even in mental disorders. Over the next 50 years, even easier and less invasive techniques for examining the whole small intestine are desired, for understanding the pathophysiology of the small intestine and for further improvements in the diagnosis and treatment of small-intestinal disease.

• References

• 1 Deyhle P, Jenny S, Fumagalli J. et al. Endoscopy of the whole small intestine. Endoscopy 1972; 4: 155-157
• 2 Hiratsuka H. [Endoscopic diagnosis in the small intestine]. Stomach Intestine 1972; 7: 1679-1685 (Japanese)
• 3 Yamamoto H, Sekine Y, Sato Y. et al. Total enteroscopy with a nonsurgical steerable double-balloon method. Gastrointest Endosc 2001; 53: 216-220
• 4 Yamamoto H, Ell C, Binmoeller KF. Double-balloon endoscopy. Endoscopy 2008; 40: 779-783
• 5 Monkemuller K, Weigt J, Treiber G. et al. Diagnostic and therapeutic impact of double-balloon enteroscopy. Endoscopy 2006; 38: 67-72
• 6 Aabakken L, Bretthauer M, Line PD. Double-balloon enteroscopy for endoscopic retrograde cholangiography in patients with a Roux-en-Y anastomosis. Endoscopy 2007; 39: 1068-1071