Introduction

In the era of magnetic resonance cholangiopancreatography and endoscopic ultrasound, endoscopic retrograde cholangiopancreatography (ERCP) has become a procedure with a primarily therapeutic focus (e.g., access to and through stenoses, removal of stones, or drainage of cysts).^1–4 If used as a diagnostic procedure, ERCP is more often performed to sample tissue by the introduction of cytology brushes or biopsy forceps or to facilitate direct cholangioscopy. Major papilla sphincterotomy is mandatory in most cases to achieve adequate access for the introduction of instruments and drainage catheters. General issues related to cannulation and sphincterotomy have already been discussed in Chapter 37. The present chapter focuses on variations of the standard technique that can be used by advanced endoscopists. The variations in technique have to be performed with caution and adapted to the individual case. Important general issues are discussed first.

Proper Endoscope

The standard endoscope for most indications is a therapeutic side-viewing duodenoscope with an instrumentation channel of 3.7 to 4.2 mm. There are only very rare situations in which a smaller diagnostic duodenoscope offers advantage, such as duodenal stenoses. For examination of a pediatric patient younger than 2 years and in a case in which the papillary orifice is localized on the inner side of a duodenal diverticulum, a standard 11.5-mm duodenoscope may be advantageous. A disadvantage of a smaller scope is a channel of only 2.8 to 3.2 mm, which makes the implantation of 10-Fr to 12-Fr stents impossible and the use of two guidewires difficult. A previous argument had been the better deflection of the elevator (Albarran’s lever) using standard 6-Fr to 7-Fr catheters or tiny instruments. Changes in elevator design in the last decade have eliminated this problem with therapeutic duodenoscopes. However, grooming of standard catheters to facilitate cannulation of the common bile duct (CBD) can still be helpful in certain situations.

Access to and cannulation of the papilla in case of a Billroth II (BII) resection (Figs. 39.1 and 39.2) is generally possible with a comparable success rate using a prograde or a side-viewing endoscope; this is described later.^5–7 Gastroscopes work only in a few usually older BII patients without enteroenteric anastomosis, but gastroscopy may be helpful for initial inspection and orientation of the anastomoses. In patients with a very long afferent loop and in patients after gastrectomy with Roux-en-Y anastomosis, a pediatric colonoscope or enteroscope longer than 170 cm is needed in case of a forward-viewing endoscopic approach. Although the forward-viewing instrument facilitates intubation of the afferent loop at the gastroenteric anastomosis, it typically provides only a tangential view of the papilla.⁸

Fig. 39.1 Billroth II anatomy: endoscopic access. Endoscopic view at the gastrojejunal (A) and enteroenteral (Braun) anastomosis (B). The endoscopist should use an afferent loop and stay on the same side of the enteral wall when passing the enteroenteral anastomosis (oval).

(Modified from Soehendra N, Binmoeller KF, Seifert H, et al: Therapeutic endoscopy: color atlas of operative techniques for the gastrointestinal tract, New York, 1997, Thieme Medical Publishers.)

Fig. 39.2 Billroth II cannulation. View of the papilla from below with inverted anatomy.

(Modified from Soehendra N, Binmoeller KF, Seifert H, et al: Therapeutic endoscopy: color atlas of operative techniques for the gastrointestinal tract, New York, 1997, Thieme Medical Publishers.)

The duodenoscope offers the advantage of improved visual orientation to the ampulla. The elevator is helpful to manipulate and maintain accessories. A duodenoscope is preferred by many endoscopists if applicable.^5,8 In a difficult anatomic situation with a steep afferent loop, it can be helpful first to place a 0.035-inch, 450-cm guidewire (polytetrafluoroethylene-coated standard Seldinger wire; PNB Medical, Denmark) into the blind proximal end of the duodenal stump under radiographic control as a pathfinder for the side-viewing instrument.

Locating the Papilla

Although the natural position of the papilla is on the inner side of the duodenal C-loop in the midportion of the descending duodenum, it may be difficult to find in some instances. The papilla may be located toward the lower portion, which often requires a very “long” endoscope position. The papilla can be cloaked by duodenal folds, and often only the frenulum, as a caudal longitudinal extension, indicates that the papillary orifice may be close. In the search for the papilla, an atraumatic ERCP catheter or sphincterotome can be helpful to lift and separate folds. Duodenal diverticula have to be inspected carefully. One way to expose the inner side of the diverticulum is to push the mucosa gently from the outer rim of the diverticular ring caudally with an ERCP catheter. The papillary orifice often appears by being pulled from the inner side of the diverticulum toward the edge of the opening. Submucosal injection into the bottom of the diverticulum has been described to lift the papillary orifice. However, one should keep in mind the very thin wall of the diverticulum with the risk of potentially severe complications owing to needle perforation and retroperitoneal leak and a potential edematous compression of the papillary orifice.⁹

In rare cases, it can take 20 minutes or longer to find the papilla. Sometimes, the papilla is located more proximally. This situation occurs after Billroth I resection. Very rarely, the papilla is located in the duodenal bulb. An edematous duodenum after an acute attack of chronic pancreatitis or advanced cancer of the head of the pancreas can make successful localization and cannulation of the papilla impossible. A radiologically guided percutaneous-transhepatic rendezvous procedure and endoscopic ultrasound–guided puncture into the biliary system are options in these cases.^10–14

Park and coworkers¹⁵ described using methylene blue to find the minor papilla orifice in patients with a complete pancreas divisum. After spraying dye onto the area of the papilla, pancreatic secretions wash away the dye from papillary orifice. Intravenous secretin (Secrelux, Sanochemia Diagnostics, D-41460 Neuss) can help in this case to stimulate pancreatic secretion and to identify the pancreatic orifice for minor papilla cannulation. Secretin is expensive, however, and should not be given in case of pancreatic obstruction or acute pancreatitis.

Cannulation

A well-sedated patient is the prerequisite for a smooth intervention. Before cannulation, the papilla should be observed carefully, and the endoscopist should imagine the natural course of the CBD. A long papillary roof delineating the distal bile duct above the horizontal fold (plica horizontalis) may be helpful in determining its axis and course (Fig. 39.3). For cannulation of the CBD, the papilla should be viewed from below, and the catheter direction should be steep and within the axis of the papilla. Curving the distal end of the catheter upward often facilitates achievement of this angle and eases biliary cannulation. The catheter tip is introduced into the papillary orifice and gently pushed forward while the elevator is lifted and the bile duct is cannulated. For primary pancreatic duct cannulation (Fig. 39.4), the endoscope position remains at the level of the papilla, and the catheter direction is roughly horizontal. Although the course of the pancreatic duct leads toward the 5 o’clock position viewed from directly in front of the papilla, in our experience it can be helpful, in a native papilla, to turn the small wheel of the endoscope forward and cannulate the papillary orifice from the right to the left followed by only gentle injection of contrast material.

Fig. 39.3 For primary cannulation of the common bile duct using a standard catheter and a therapeutic duodenoscope, it often helps first to intubate the papillary orifice with the catheter (A) and then to change the angle of the catheter by gently advancing the endoscope (B). Alignment with the axis of the papilla is important in biliary cannulation (C and D).

(Modified from Soehendra N, Binmoeller KF, Seifert H, et al: Therapeutic endoscopy: color atlas of operative techniques for the gastrointestinal tract, New York, 1997, Thieme Medical Publishers.)

Fig. 39.4 A–D, Pancreatic cannulation. Flat position of the catheter facing the papilla at the same level (A). If common bile duct cannulation was performed first, pulling back the endoscope facilitates cannulation (B and C) and changes the direction of the catheter within the papilla (D).

(Modified from Soehendra N, Binmoeller KF, Seifert H, et al: Therapeutic endoscopy: color atlas of operative techniques for the gastrointestinal tract, New York, 1997, Thieme Medical Publishers.)

Catheter versus Sphincterotome Cannulation

The primary use of a catheter or a sphincterotome for biliary cannulation is controversial. The traditional first choice is a regular tapered 6-Fr catheter with a 4-Fr tip accepting a 0.035-inch wire that is used for biliary cannulation of the papilla and may serve for easier intrahepatic cannulation in biliary stenoses. The advantage of a prebent standard catheter over a 6-Fr sphincterotome is the higher flexibility and even less traumatic access owing to a high sensitivity even for narrow papillary channels. However, the use of a regular sphincterotome to initiate cannulation of the bile duct potentially allows variability and improvement of the vertical angle in which the bile duct is cannulated alongside the axial alignment.¹⁶

After correct adjustment is achieved, the catheter or sphincterotome is advanced toward the papilla. It is best to approach the papilla from a distance so that the natural curve of the sphincterotome is obvious on exiting the endoscope. The tip of the sphincterotome is gently introduced into the common channel. Bowing of the sphincterotome tip usually eases the tip into the mouth of the CBD; when this happens, a characteristic “give” often occurs. Relaxing the wire to straighten the tip and gently withdrawing the endoscope anchor the tip of the sphincterotome further within the distal bile duct. Simply advancing the sphincterotome now invariably leads to deep cannulation.

New devices are constantly being developed to improve the success rate of ERCP.^16,17 Two studies evaluated the use of a new steerable catheter (SwingTip; Olympus, Tokyo, Japan) to achieve bile duct cannulation. Igarashi and coworkers¹⁸ reported successful cholangiography in 175 of 195 cases (90.5%) with a standard catheter; using the SwingTip catheter in cases in which the standard catheter failed, it was possible to carry out cholangiography in 11 of 17 patients (64.7%), increasing the overall success rate to 95%. Laasch and colleagues¹⁷ conducted a prospective randomized controlled trial comparing the success rate in performing cholangiography and bile duct cannulation with three different catheters: a standard ERCP cannula, a short-nosed sphincterotome, and the SwingTip device. The study included 312 patients at two tertiary referral centers. Both steerable catheters were significantly better than the standard catheter for performing cholangiography (P