The power suction maneuver in single-balloon enteroscopy

Up until the past 10 years, the diagnostic work-up for small-bowel diseases, employing modalities such as contrast studies and computed tomography, was poor and mostly unyielding. Push enteroscopy and intraoperative enteroscopy were performed in a few experienced institutions. However, it is not possible to reach all portions of the jejunum and the ileum by the push enteroscope, while intraoperative enteroscopy demands a surgical route. The introduction of capsule endoscopy has been a long-awaited advance in the diagnosis of small-bowel lesions. Wireless capsule endoscopy has overcome obstacles, but still has some weaknesses, such as the inability to biopsy and treat the detected lesions. Capsule endoscopy also has some limitations in patients with surgical strictures and in those with altered gastrointestinal anatomy, including Roux-en-Y reconstruction [1] [2] [3].

Double-balloon enteroscopy (DBE) (Fuji Photo Optical Co., Ltd., Saitama, Japan) is a new technique introduced by Yamamoto et al. in 2001 [2] [3]. DBE can be used to examine the entire small bowel by the oral and anal routes. The technical procedure for DBE is established and DBE is available for routine clinical use in many countries. However, handling difficulties in DBE include attaching a balloon to the tip of the scope before each examination, and inflating/deflating the two balloons at every insertion. The recently developed single-balloon enteroscopy (SBE) system claims to simplify the examination sequence [4]. SBE is a new endoscopic method for the examination of the small intestine. The SBE system consists of two parts: an overtube with a balloon on the distal end and an endoscope 200 cm in length. No balloon is attached to the distal end of the endoscope, but it is hook-shaped, and manipulation of the up-angle or down-angle enables exploration of the small intestine [4]. Since the introduction of DBE, examination techniques have become established. It is obvious that the two systems are different in some ways such that you can not use the same examination maneuvers with SBE. There is not enough knowledge about the maneuvers that would make the SBE examination efficient and less harmful.

The insertion technique for both SBE and DBE is similar. The overtube is soft and flexible and can be inserted easily over the scope. The balloon on the overtube creates a fixed support, which enables the endoscope to be inserted further. The difficult part of the method is to hold the small intestine. After the maximum insertion is achieved, the tip of the endoscope is bent to its maximum up-angle or down-angle. Using this hook shape of the scope in SBE, instead of an inflated balloon on the tip as in DBE, the endoscope can hold the small intestine in position and the overtube can be inserted further without stretching the intestine. When the distal tip of the overtube reaches just before the bent region of the endoscope, the overtube balloon is inflated to grip the intestine. After returning the tip of the endoscope to the neutral position, both the endoscope and the overtube are gently withdrawn in order to shorten the intestine. Repeating these maneuvers enables the endoscope and overtube to be inserted further into the intestine [4].

Instead of the hook shape, we use maximum suction power to hold the small intestine during the insertion of the overtube. After the endoscope has been maximally inserted, the endoscope view is centered and maximum suction used, collapsing the intestine onto the tip. The overtube is inserted to the bent part of the scope while the suction is held. After the balloon on the overtube is inflated, the suction is released so that the intestinal lumen comes into view. The suction acts like the balloon on the tip in DBE and experience shows it is strong enough to hold the intestine. This maneuver has the advantage of causing less damage to the mucosa than does the hook shape ([Fig. 1] and [Fig. 2]). This maneuver is practical and safe, especially in the proximal segments of the intestine, for both the oral and the anal routes. Power suction gives rise to a little suction polyp, that diminishes soon after the suction ceases, whereas the hook shape causes mucosal lacerations that range from superficial abrasions to a theoretical risk of perforation due to the rigidity of the endoscope tip.

Fig. 1 Deep erosion viewed just after the standard maneuver using the hook shape during single-balloon enteroscopy (SBE).

Fig. 2 Suction polyp, which diminishes shortly after suction ceases, due to power suction maneuvers during SBE.

We have been using the SBE system for 8 months for diagnosis of small-intestinal diseases and are still on the first steps of our learning curve. We have used this maneuver without the hook shape in six patients, four of whom underwent oral and anal examination, while the other two underwent anal examination only. The achieved maximum depth of insertion ranged from 200 to 300 cm for the oral route and from 180 to 240 cm for the anal route. We feel this technique gives us a little bit more examination depth and ease of insertion with the same procedure time when we compare it to our former experiences.

Tsujikawa et al. state that the anal insertion route often causes sharp bends of the small intestine in the pelvic region. In this situation, the balloon on the DBE scope seems to be more helpful than the hook shape of the SBE scope, which makes the insertion efficiency of SBE inferior to that of DBE. The hook shape of the endoscope end may require more care than the balloon in DBE patients with adhesions or intestinal narrowing [4].

We believe that the power suction maneuver is safe and strong enough to grip the intestine without causing more harm than the rigid tip of the hook-shaped scope. In addition, the disadvantages over the DBE method, as stated by Tsujikawa, are minimized.

To sum up: we are at the beginning of the use of a new and promising method. As the experiences with both DBE and SBE grow, the indications for using them grow. It is apparent that only a small percentage of patients will need total ileoscopy. Endoscopic and histologic diagnosis of various disorders, and follow-up of certain diseases, could require a single route of examination. We should be prepared for frequent use of SBE and DBE and find ways to make them safe for patients.

We advise using the power suction maneuver in SBE instead of using the hook shape of the scope.

Competing interests: None

References

• 1 Safatle-Ribeiro A V, Kuga R, Ishida R. et al . Is double-balloon enteroscopy an accurate method to diagnose small-bowel disorders?.  Surg Endosc. 2007;  21 2231-2236
• 2 Yamamoto H, Sekine Y, Sato Y. et al . Total enteroscopy with a nonsurgical steerable double-balloon method.  Gastrointest Endosc. 2001;  53 216-220
• 3 Kaffes A J, Koo J H, Meredith C. Double-balloon enteroscopy in the diagnosis and the management of small-bowel diseases: an initial experience in 40 patients.  Gastrointest Endosc. 2006;  63 81-86
• 4 Tsujikawa T, Saitoh Y, Andoh A. et al . Novel single-balloon enteroscopy for diagnosis and treatment of the small intestine: preliminary experiences.  Endoscopy. 2008;  40 11-15