A New Method of Enteroscopy - Double-Balloon Method

The small intestine is located quite far from both the mouth and the anus. Its endoscopic approach is difficult and diseases in this organ are hard to diagnose. Although observation of the small intestine by a capsule endoscope has been reported in recent years, it is not a sufficient diagnostic method yet, because to and fro observation in an arbitrary part is impossible, and therapeutic procedures or biopsies cannot be performed with this method. We devised a new method of enteroscopy that uses 2 balloons, one attached to the tip of the endoscope and another at the distal end of a soft overtube. We reported that endoscopic observation of the entire small intestine was possible with this method using an endoscope of 200 cm in working length [1]. At this time, I would like to introduce a specifically designed endoscopic system of the double-balloon method which was developed in cooperation with Fuji Photo Optical Incorporated Company. Clinical experiences of the system will be presented.

The importance of endoscopic exploration of the small bowel has’been well documented. Established indications for small- bowel enteroscopy include unexplained digestive bleeding, radiographic abnormalities of the small intestine and chronic diarrhea or malabsorption [2]. Among the insertion techniques currently used for enteroscopy, the most frequently used method is push enteroscopy. However, deep insertion of an enteroscope is difficult with this method because the force applied to advance the instrument is diminished by the tortuous small intestine. Moreover, this causes tremendous discomfort to the patient. Therefore, even with a new- generation of video-push enteroscope along with an overtube, the depth of insertion is at most 160 cm beyond the ligament of Treitz, which is far less than the length of the small intestine, which is approximately 14 feet (430 cm) [3].

At present, intra-operative enteroscopy is the most reliable procedure for total visualization of the small intestine. Using this method, the passage of the enteroscope is assisted by the surgeon during open laparotomy. Although the technique is not difficult, an endoscopist and surgeon are required to perform the procedure. The most significant disadvantage of this method, however, is its invasive nature.

Nonsurgical total small bowel enteroscopy has been successfully accomplished by 2 different methods, one using an instrument pushed over a previously passed guide-string [4] [5] [6], whereas the other relies on peristalsis to propel a long, flexible fiberoptic endoscope through the intestine [7]. Both methods are tedious, uncomfortable and time consuming. The guide-string for the ”ropeway ” method may take several days to pass from mouth to rectum. Stretching of the string can damage the small bowel mucosa and cause tremendous pain and discomfort that necessitates the use of general anesthesia. The limitations of the ”sonde” procedure are the lack of both tip deflection and intervention capabilities [2]. Despite the ability to inspect the entire small bowel, neither method has gained general clinical acceptance.

Since each of the currently available methods has limitations, the development of relatively noninvasive and steerable enteroscope with intervention capability, which can explore entire small bowel, would be highly advantageous.

References

• 1 Yamamoto H, Sekine Y, Sato Y, Higashizawa T, Miyata T, Iino S, Ido K, Sugano K. Total enteroscopy with a nonsurgical steerable double-balloon method.  Gastrointest Endosc. 2001;  53 216-220
• 2 Waye J D. Enteroscopy.  Gastrointest Endosc. 1997;  46 247-256
• 3 Landi B, Tkoub M, Gaudric M, Guimbaud R, Cervoni J P, Chaussade S, Couturier D, Barbier J P, Cellier C. Diagnostic yield of push-type enteroscopy in relation to indication.  Gut. 1998;  42 421-425
• 4 Hiratsuka H, Hasegawa M, Ushiromachi K, Endo T, Suzuki S, Nishikawa F, Yamasaki H, Kamisuna N. Endoscopic diagnosis of the small intestine.  Stomach Intestine. 1972;  7 1679-1685
• 5 Deyhle P, Jenny S, Fumagalli J, Linder E, Ammann R. Endoscopy of the whole small intestine.  Endoscopy. 1972;  4 155-157
• 6 Classen M, Frühmorgen P, Koch H, Demling L. Peroral enteroscopy of the small and the large intestine.  Endoscopy. 1972;  4 157-162
• 7 Tada M, Akasaka Y, Misaki F, Kawai K. Clinical evaluation of a sonde-type small intestinal fiberscope.  Endoscopy. 1977;  9 33-38