Selective Biliary Cannulation Using Pancreatic Guide-Wire Placement: Further Evidence Needed to Support the Use of an Already Known Technique

We read with interest the recent article by Maeda et al. [1] about the placement of a guide wire in the pancreatic duct to facilitate selective deep biliary cannulation in difficult cases. We have been using this technique for almost 4 years at our center, since it was previously described by Dumonceau et al. in 1998 [2]. Our experience with the use of this technique has been satisfactory (it increases the rate of bile duct cannulation, with no apparent increase in the rate of adverse events), but it will only be possible to recommend the wider use of this procedure for bile cannulation after the conclusions of an ongoing multicenter trial have been published.

For several reasons, the reliability of the conclusions drawn by Maeda et al. may be questioned. The cannulation rate described by the authors is clearly poor (50 % with the conventional maneuver and the number of endoscopic retrograde cholangiopancreatographies (ERCPs) performed was small (107 procedures in 6 months is equivalent to approximately four ERCPs per week). The type of patient included is not clearly defined in the article, but it is notable that the rate of therapeutic procedures was extremely low (10 sphincterotomies out of 107 ERCPs). This may have meant that the expertise of the endoscopists concerned was limited - leading to their definition of ”a difficult case of biliary cannulation” as failure to introduce the catheter after attempting to do so for 10 min.

The use of a guide wire to enter the bile duct is intended to reduce trauma to the papilla and facilitate bile duct cannulation, and this technique is recommended by some experts [3] [4] and also in classic textbooks [5], based on its usefulness and safety. However, it has never been formally compared with other techniques. The initial method used by the authors to cannulate the bile duct does not include the use of a guide wire, and it is difficult to understand why a double-guide technique was used instead of an easier and safer single-guide system as the first step.

An ongoing multicenter trial is attempting to evaluate the extent to which pancreatic guide-wire insertion (with the double-guide technique) is of value in facilitating biliary cannulation in difficult cases - which are those in which success is not achieved after three attempts to enter the bile duct with the help of a guide wire (single-guide technique). This trial will allow accurate assessment of the benefits in terms of the cannulation success rate and whether or not the rate of adverse events (post-ERCP pancreatitis) is increased in a more appropriate scenario of truly difficult cases, at different levels of expertise. The results should be of considerable interest for patients with a high risk of complications.

We believe that the difficulty of managing the papilla should lead the endoscopist to take a conservative, step-by-step approach to bile duct cannulation. Forthcoming data will clarify whether pancreatic manipulation should be attempted by expert endoscopists once less aggressive methods of biliary cannulation have failed. We are therefore in agreement with Devière [6] that one should exercise extreme caution before recommending wider use of the double-guide technique. In inexperienced hands, manipulating the pancreatic duct may lead to adverse events that must be avoided.

References

• 1 Maeda S, Hayashi H, Hosokawa O. et al . Prospective randomized pilot trial of selective biliary cannulation using pancreatic guide-wire placement.  Endoscopy. 2003;  35 721-724
• 2 Dumonceau J M, Devière J, Cremer M. A new method of achieving deep cannulation of the common bile duct during endoscopic retrograde cholangiopancreatography.  Endoscopy. 1998;  30 80
• 3 Classen M, Born P. Endoscopic sphincterotomy. In: Tytgat G, Classen M, Waye JD, Nakazawa S, (ed). Practice of therapeutic endoscopy. 2nd ed.  London; Saunders 2000: 134
• 4 Sherman S, Uzer M F, Lehman G A. Wire-guided sphincterotomy.  Am J Gastroenterol. 1994;  89 2125-2129
• 5 Cotton P, Williams C. Practical gastrointestinal endoscopy.  Oxford; Blackwell Science 1996
• 6 Devière J. Using the pancreas for bile duct cannulation?.  Endoscopy. 2003;  35 750-751