Endoscopic retrograde cholangiopancreatography




Photodynamic therapy was written by Jacques Etienne.



Introduction


Introduction


Although almost all endoscopic retrograde cholangiopancreatography (ERCP) is undertaken with a view to a therapeutic intervention, an understanding of the basic concepts is essential before progressing to therapeutic ERCP. This chapter is divided into two sections. The first section introduces the basic techniques required to selectively cannulate the common bile duct or pancreatic duct, as well as the equipment required for ERCP; how to ensure that you obtain the optimum images from the procedure; and what pitfalls to watch out for in image interpretation. The second part of the chapter discusses therapeutic procedures and the complications associated with ERCP.




Indications for diagnostic ERCP





  • Summary



  • Introduction 371


  • 1

    Indications 371



Key Points





  • The commonest cause of litigation in ERCP is that the procedure was not indicated.



  • Diagnostic ERCP should be avoided, and has been replaced by EUS and MRI.



  • If EUS is indicated, it should be performed before ERCP, as a sphincterotomy or stent placement limits the ability to adequately visualize the ampullary region.




Introduction


It is essential that an endoscopic retrograde cholangiopancreatography (ERCP) is undertaken for an appropriate indication. The commonest cause of litigation in ERCP is that the procedure was not indicated. Consensus and association guidelines are available and can be found in the further reading section. ERCP is primarily a therapeutic procedure. Non-invasive imaging (EUS or MRI) should be performed if an intervention is unlikely to be required. If EUS is indicated, it should be performed before ERCP when possible, as a sphincterotomy or stent insertion greatly limits the ability to assess the papilla and distal common bile duct.



Indications



Biliary





  • Choledocholithiasis : Routine ERCP is not indicated for assessment of common bile duct stones in patients undergoing laparoscopic cholecystectomy, where there is a low probability of having choledocholithiasis. ERCP is indicated in patients with a high suspicion of choledocholithiasis (jaundice, dilated common bile duct, cholangitis, or acute pancreatitis secondary to choledocholithiasis).



  • Malignancy : ERCP is useful in assessing ampullary lesions. It can be used to acquire tissue in patients with biliary or pancreatic malignancy, although it is not always diagnostic. ERCP can be used to palliate malignant biliary obstruction.



  • Biliary strictures : ERCP is effective in treating benign bile duct strictures.



  • Bile duct leak : ERCP should be the first procedure used to treat bile duct leak.



  • Sphincter of Oddi dysfunction (SOD) : ERCP with sphincterotomy is indicated in type I. Patients with type II SOD should undergo manometry and may benefit from sphincterotomy if elevated pressure (>40 mmHg) is found.




Pancreatic





  • Acute pancreatitis : ERCP has no role in acute pancreatitis, with the exception of acute pancreatitis associated with choledocholithiasis. ERCP is indicated in patients with acute recurrent pancreatitis to assess and treat the cause.



  • Chronic pancreatitis : ERCP is useful for treating symptomatic strictures, pancreatic duct stones, and for draining pseudocysts.



  • ERCP is useful for the management of pancreatic duct leak or duct disruption.



Further Reading


  • Adler DG, Baron TH, Davila RE, et. al.: ASGE guidelines: the role of ERCP in diseases of the biliary tract and the pancreas. Gastrointest Endosc 2005; 62: pp. 1.
  • Cohen D, Bacon BR, Berlin JA, et. al.: National Institutes of Health state-of-the-science conference statement: ERCP for diagnosis and therapy. Gastrointest Endosc 2002; 56: pp. 803.




  • Drugs used in ERCP





    Key Points





    • Glucagon decreases peristalsis and can be used to decrease duodenal motility.



    • Secretin stimulates secretion of pancreatic juice and can be used to facilitate identification of the ampulla of Vater and the accessory papilla.




    Introduction


    In addition to the usual medications used for sedation (see Ch. 2.3 ), glucagon and secretin are sometimes use to aid identification of the major or minor papillae or assist cannulation.



    Glucagon


    Glucagon causes transient relaxation of the smooth muscles of the GI tract, thus decreasing motility. Glucagon has an onset of action of 1 min, with a duration of effect of 20–30 min. It should be avoided in patients undergoing sphincter of Oddi manometry.


    Dose





    • The initial dose is 0.25–0.5 mg IV.



    Side-effects





    • Nausea, vomiting



    • Hypertension, hypotension, tachycardia



    • Hypersensitivity or allergic reaction.



    Use with caution





    • Adrenal insufficiency



    • Chronic hypoglycemia



    • Elderly



    • Chronic obstructive airways disease (COAD).



    Contraindications





    • Phaeochromocytoma



    • Insulinoma



    • Known hypersensitivity to glucagon.



    Use in pregnant women





    Interactions





    • Patients on beta-blockers may have an exaggerated increase in heart rate and blood pressure.



    Reversal agent





    • None.




    Secretin


    Secretin causes stimulation of pancreatic secretions and can be used to facilitate identification of the ampulla of Vater and the accessory papilla. Secretin has a rapid onset of action, with levels returning to baseline within 90 min.


    Dose





    • The initial dose is 0.2 µg/kg over 1 min IV (Reconstitute using 8 mL of sodium chloride. Each reconstituted mL contains 2 µg of secretin.)



    Side-effects





    • Nausea, vomiting



    • Flushing



    • Abdominal pain.



    Contraindications





    • Known hypersensitivity to secretin



    • Acute pancreatitis.



    Use in pregnant women





    Interactions





    • Anticholinergic drugs may decrease the response to secretin.



    Reversal agent





    • None.






    Drugs used in ERCP





    Key Points





    • Glucagon decreases peristalsis and can be used to decrease duodenal motility.



    • Secretin stimulates secretion of pancreatic juice and can be used to facilitate identification of the ampulla of Vater and the accessory papilla.




    Introduction


    In addition to the usual medications used for sedation (see Ch. 2.3 ), glucagon and secretin are sometimes use to aid identification of the major or minor papillae or assist cannulation.



    Glucagon


    Glucagon causes transient relaxation of the smooth muscles of the GI tract, thus decreasing motility. Glucagon has an onset of action of 1 min, with a duration of effect of 20–30 min. It should be avoided in patients undergoing sphincter of Oddi manometry.


    Dose





    • The initial dose is 0.25–0.5 mg IV.



    Side-effects





    • Nausea, vomiting



    • Hypertension, hypotension, tachycardia



    • Hypersensitivity or allergic reaction.



    Use with caution





    • Adrenal insufficiency



    • Chronic hypoglycemia



    • Elderly



    • Chronic obstructive airways disease (COAD).



    Contraindications





    • Phaeochromocytoma



    • Insulinoma



    • Known hypersensitivity to glucagon.



    Use in pregnant women





    Interactions





    • Patients on beta-blockers may have an exaggerated increase in heart rate and blood pressure.



    Reversal agent





    • None.




    Secretin


    Secretin causes stimulation of pancreatic secretions and can be used to facilitate identification of the ampulla of Vater and the accessory papilla. Secretin has a rapid onset of action, with levels returning to baseline within 90 min.


    Dose





    • The initial dose is 0.2 µg/kg over 1 min IV (Reconstitute using 8 mL of sodium chloride. Each reconstituted mL contains 2 µg of secretin.)



    Side-effects





    • Nausea, vomiting



    • Flushing



    • Abdominal pain.



    Contraindications





    • Known hypersensitivity to secretin



    • Acute pancreatitis.



    Use in pregnant women





    Interactions





    • Anticholinergic drugs may decrease the response to secretin.



    Reversal agent





    • None.





    Equipment





    • Summary


    • 1

      Endoscopes 373


    • 2

      ERCP equipment 373


    • 3

      Radiology suite and equipment 376



    Key Points





    • All equipment should be available in duplicate.



    • A therapeutic duodenoscope is used for the majority of procedures.



    • A forward viewing endoscope may be required in patients with altered anatomy.



    • Short wire systems have been developed which allow for rapid exchange, control of the wire by the endoscopist and avoid the need for an experienced assistant.



    • All baskets should be compatible with a lithotripter.



    • High quality radiological equipment is essential.





    Endoscopes



    Video duodenoscope





    • Almost all ERCPs are performed with a ‘therapeutic’ duodenoscope which has a 4.2 mm operating channel. This duodenoscope can be used for both diagnostic and therapeutic procedures. This size instrument channel allows insertion of all accessories and as well as performing cholangioscopy.



    • A ‘diagnostic’ duodenoscope is thinner and has a smaller instrument channel. The instrument channel will only allow the passage of an Fr stent. As their diameter is slimmer, they are useful where there is altered anatomy (i.e. Billroth I), a stricture, or if an ERCP is being performed in a child or young adult.




    Forward viewing endoscope





    • For patients with Billroth II, start with a standard duodenoscope; however, ensure that a forward viewing endoscope is available. Options include using an enteroscope by itself, or augmented enteroscopy with a single balloon, double balloon or Spirus overtube (see Ch. 5.2 ). A pediatric colonoscope can also be used.




    ERCP equipment



    Catheters


    The choice of whether to start with a catheter or a sphincterotome is based on endoscopist preference, and also on whether a sphincterotomy is likely to be made. In cases where this is unlikely, or where a sphincterotomy has already been performed, a catheter is often used to cannulate. There are several types of catheters available. A standard catheter has a graduated, precurved tip with a single channel, which can be used for either contrast or a wire. A triple lumen catheter has two channels which allow contrast to be injected while keeping a wire in place. A taper-tip catheter has a shorter, 5 mm tip. The taper-tip catheter is sometimes useful for cannulating a stenosed or minor papilla. There is a slightly increased risk of submucosal injection with this type of catheter.



    Sphincterotomes


    The sphincterotome consists of a metal wire covered by an insulating sheath, with the distal 20–30 mm of wire exposed, and a short radio-opaque, tapered tip (5 mm). Cannulation is usually attempted with a sphincterotome if a sphincterotomy is likely. The angle of the tip of the sphincterotome can be altered, by asking the assistant to ‘tense’ the sphincterotome, which is also useful if cannulation is difficult.


    Several different types of sphincterotomes are available. A double-lumen sphincterotome allows either injection of contrast or a guidewire ( Fig. 1A ). A triple lumen sphincterotome ( Fig. 1B ) allows injection of contrast without removing the guidewire. A tapered tip (5 mm tip) ( Fig. 1D ) is sometimes used if the papilla is stenotic or to cannulate the minor papilla. In patients in whom the orientation of the biliary and pancreatic ducts are reversed (i.e. Billroth II), a special sphincterotome is available which is orientated in the opposite direction to the regular sphincterotome ( Fig. 1E ). Where sphincterotomy fails, a needle-knife sphincterotome with a retractable wire or blade with guidewire option ( Fig. 1C ) can be used. Sphincterotomes with long cutting wires ( Fig. 1G ) are no longer used due to an increased risk of bleeding and perforation. The sphincterotome with a long tip nose ( Fig. 1F ) was used prior to guidewire cannulation, but is rarely used now.




    Figure 1


    Different types of sphincterotomes. (A) A double-lumen sphincterotome allows either injection of contrast or a guidewire. (B) A triple lumen sphincterotome allows injection of contrast without removing the guidewire. (C) A needle-knife sphincterotome with a retractable wire or blade. (D) A tapered tip (5 mm tip) is sometimes used if the papilla is stenotic or to cannulate the minor papilla. (E) In patients in whom the orientation of the biliary and pancreatic ducts are reversed (i.e. Billroth II), a special sphincterotome is available which is orientated in the opposite direction to the regular sphincterotome. (F) Sphincterotome with a long tip nose was used prior to guide wire cannulation, but is rarely used now. (G) Sphincterotomes with long cutting wires are no longer used due to an increased risk of perforation bleeding and perforation.



    Balloon catheters


    Balloon catheters are used to remove either small or medium-sized stones or sludge. They can also be used to obtain a cholangiogram where there is a very dilated duct or following a sphincterotomy. Balloon catheters come either in a single size or with three different attachments which alter the size of the balloon. They are also available as wire guided if required.



    Brushes


    Wire guided brushes are available and are used to obtain tissue from suspicious strictures.



    Forceps


    Regular biopsy forceps should be available. These can be used to biopsy the ampulla where an ampullary cancer is suspected or where autoimmune pancreatitis is a possibility. They can also be used to biopsy bile duct strictures after a biliary sphincterotomy. Pediatric biopsy forceps (6 Fr) are sometimes used. These are easier to insert into the bile duct than regular biopsy forceps; however, they provide smaller samples. There may be a slightly decreased risk of complications compared with paediatric biopsy forceps than with regular biopsy forceps.


    Jumbo forceps should also be available. These are used to remove stents. Stents are easier to grasp with the jumbo forceps than a snare; however, the stent cannot be removed through the operating channel, necessitating removal and reinsertion of the duodenoscope.



    Snare


    A snare is used to remove stents. It takes a little more practice to use than the jumbo forceps; however, the stent can usually be removed through the instrument channel of a therapeutic duodenoscope avoiding removal and reinsertion of the duodenoscope.



    Clinical Tip


    How to remove a stent with a snare


    Take time to position the scope. Insert the snare and open it just above or below the distal end of the stent. If you are going to remove it though the instrument channel, place the snare as close to the distal end of the stent as possible, close the snare and withdraw it through the instrument channel. If the stent has partially migrated out of the bile duct, grasp the side flap with the snare and gently push the stent back into the bile duct. Once this is done, the distal end of the stent can be snared and the stent removed.




    Wires


    Wires are an essential part of the ERCP armamentarium. A wire consists of a nitinol or stainless steel core with a smooth coating. The type of coating determines the performance characteristics of the wire. A hydrophilic wire consists of a nitinol core with a polyurethane coating covering the entire length of the wire. Hydrophilic wires are often used for difficult cannulations (i.e. stricture at the hilum). They are excellent at navigating tight, difficult strictures but their hydrophilic coating means that they are more difficult to handle for the assistant. Hybrid wires combine regular wire with a hydrophilic section. The aim of these wires is to give the ease of use of the non-hydrophilic wire, with the ability to traverse a tight stricture of the hydrophilic wires. PTFE or Teflon coated wires were used in the past, but are rarely used nowadays, as they must be removed prior to performing a sphincterotomy due to the risk of conducting current.


    Wires come with a variety of tips. A straight tip is usually used; however, an angled tip is useful if a tight stricture is encountered. They also come in different widths: 0.035 inch is the most commonly used, though a 0.025 inch or 0.018 inch may be required to pass a tight stricture.



    Clinical Tip


    How do you exchange over a wire?


    The endoscopist sets the pace of the exchange and watches the monitor to ensure that the wire does not move. The assistant should watch the hands of the endoscopist and move at the same speed. Most wires are made in two colors so that it is easy to see if the wire is moving. The distal end of the wire are often made of a different color (i.e. yellow and black with a pure black distal end) so that if a wire has moved significantly it will be obvious before it comes out of the duct. If it does move, stop, check the position of the wire with fluoroscopy, and once the wire is in a secure position, restart the exchange.




    Short wire system


    The classic system is a ‘long’ wire which is manipulated by an assistant. This is exchanged by the assistant advancing the wire at the same rate as the physician withdraws the instrument (see clinical tip box). With the long wire system, an experienced assistant is essential to the success of the procedure. Short wire systems have been developed which allow rapid exchange over the wire and give control of the wire to the endoscopist. The potential advantages of the short wire system include:




    • Rapid exchange



    • No need for an experienced assistant



    • Control of the wire by the endoscopist.



    They are three components to the short wire system:




    • Short wires (185–270 cm vs 400–460 cm)



    • Locking device for the wire



    • Devices designed to be exchanged over the short wire platform.



    There are currently three short wire systems. The V system (Olympus, Toyko, Japan), contains the ‘V’ locking device. This is an elevator with a V-shaped groove on the elevator, which acts as an internal wire lock ( Fig. 2 ), securing the wire and allowing devices to be removed over the wire without exchanging with an assistant.




    Figure 2


    V-Scope. (A,B) Demonstrate how the V-shaped elevator captures the wire, allowing for rapid removal of devices without formal exchange with an assistant.

    (From Shah R et al. Short-wire ERCP systems. Technology status evaluation report. Gastrointestinal Endoscopy 2007;66:650-655.)


    Both the Fusion System (Cook Endoscopy; Winston Salem, NC) and the RX Biliary System (Boston Scientific, Natick, MA) consist of short wire systems with external wire locking systems. They both have specially designed biopsy caps, which prevent leaking of air or bile. The Fusion System incorporates a wire lock with port cap ( Fig. 3B ), while the RX Biliary System has a separate anti-leak biopsy cap, and a wire lock which is attached to the handle of the endoscope and allows fixation of two wires ( Fig. 3A ). A large variety of compatible devices are available (see Shah et al 2007, for information on available devices) including sphincterotomes and stents.




    Figure 3


    RX System and Fusion System. (A) The RX System has an anti-leak biopsy cap and wire locking device. (B) The Fusion System has a specially designed biopsy cap and a locking device which can hold up to two wires.

    (From Shah R et al. Short-wire ERCP systems. Technology status evaluation report. Gastrointestinal Endoscopy 2007;66:650-655.)



    Other equipment


    A selection of other equipment should be available. This includes:




    • A selection of Dormia baskets in various shapes and sizes should be available; the small and medium sizes are the most used. Rigid baskets which do not deform, are preferred to flexible ones (baskets made of nitinol do not deform). All baskets should be compatible with a lithotripter



    • Nasobiliary and nasopancreatic drains



    • Small and large snares if an ampullectomy is being performed



    • Clips



    • Epinephrine (adrenaline) and injection needle



    • Mechanical lithotripter



    • Electrohydraulic lithotripter



    • Electrocautery unit.




    Radiology suite and equipment


    Ideally the ERCP room should be an integral part of the endoscopy suite, thus avoiding the need to move equipment and personnel. The ERCP room should be an adequate size to allow for the amount of equipment and personnel required, and should be provided with equipment to allow propofol or general anesthesia if necessary. It is essential that high quality radiological equipment is used. The ideal equipment is a digital remote-control table operated by a radiographer.



    General radiology equipment





    • Articulated arm supplying fluids and electrical current over the video console (with several power points, two suction inlets, one oxygen point, one nitrous oxide point)



    • An X-ray generator with continuous and pulsed exposure capability (most now have high frequency generators which provide excellent exposure reproducibility and automatic brightness control)



    • Bifocal X-ray tube



    • Collimation and filtration



    • High definition image intensifier



    • Digital image recording and display using a minimum of two display screens



    • The patient table should minimize X-ray attenuation while providing sufficient strength to support large patients. The configuration most commonly used in GI is a mobile C-arm with an under table X-ray tube



    • Standard radiation protection aprons, eye shielding and standard radiation protection systems, including lead barriers between the patient and operator



    • Foot pedal to acquire images.



    Further Reading


  • Kethu SR, Adler DG, Conway JD, et. al.: ERCP cannulation and sphincterotomy devices. Gastrointest Endosc 2010; 71: pp. 435-445.
  • Shah RJ, Somogyi L, Petersen BT, et. al.: Short-wire ERCP systems. Technology status evaluation report. Gastrointest Endosc 2007; 4: pp. 650-657.




  • Checklist before starting an ERCP





    • Summary


    • 1

      Patient checklist 377


    • 2

      Endoscopist checklist 377


    • 3

      Patient positioning 377



    Key Points





    • Always ensure that you have reviewed the patient notes and imaging.



    • Check the duodenoscope and equipment before starting.





    Patient checklist





    • Patient preparation (see Chapters 2.1, 2.2 and 2.3 )



    • Admission notes



    • Previous imaging



    • Liver function tests (AST, ALT, GGT, alkaline phosphatase, and bilirubine)



    • Pancreatic tests (amylase and lipase)



    • Anaesthetic review



    • Informed consent



    • INR, platelets




      • Usually only required in patients with evidence of a bleeding disorder, liver disease, malnutrition, prolonged therapy with antibiotics associated with clotting factor deficiencies, prolonged biliary obstruction or in patients who are receiving anticoagulation therapy




    • Venous access in right arm



    • Antifoam solution is sometimes given prior to the procedure.




    Endoscopist checklist





    • Check that the endoscope is aspirating, blowing air and water correctly, and that white balancing has been performed



    • Make sure that endoscopy recording equipment is available and working.




    Patient positioning





    • The patient is placed in the left lateral decubitus position with their left arm at their back



    • Patients should preferably be placed in a supine position, if access to the minor papilla is required or in cases of hilar stenosis, to allow optimal visualization of the biliary tree.






    Basic ERCP technique





    • Summary


    • 1

      Inserting the duodenoscope and positioning over the papilla 378


    • 2

      Locating the papilla 378


    • 3

      Cannulating the major papilla 380


    • 4

      Failure to cannulate the desired duct 381


    • 5

      Cannulating the papilla beside a diverticulum 382


    • 6

      Cannulating a stricture 382


    • 7

      Cannulating the minor papilla 384


    • 8

      ERCP in patients with altered anatomy 384


    • 9

      Successful cannulation rate 390


    • 10

      ERCP in children 390



    Key Points





    • Patience is key to successful cannulation.



    • The major papilla usually has a ‘neck tie’ appearance.



    • The minor papilla is usually 2 cm proximal and anterior to the major papilla and is usually most easily identified and cannulated with the patient supine.



    • ERCP in patients with altered anatomy is associated with lower success rates and higher complication rates. It is essential to know what type of surgery has been performed. Augmented enteroscopy, with single/double balloon or spiral enteroscopy, is sometimes required.





    Inserting the duodenoscope and positioning over the papilla


    How to intubate and position the duodenoscope in front of the papilla is illustrated in Figure 1 . Gently insert the duodenoscope to the upper esophageal sphincter. The esophagus is intubated blindly with gentle forward pressure and slight clockwise rotation. If there is resistance STOP, and change to a forward viewing gastroscope to exclude anything which may cause difficulties with intubation (i.e. Zenker’s diverticulum/stricture). Due to the side-viewing nature of the duodenoscope, a full view of the esophagus is not possible. Once the duodenoscope passes the gastroesophageal junction, make a half turn clockwise and follow the lesser curve to the pylorus. As the duodenoscope is side viewing, the duodenum is entered by placing the pylorus in the ‘setting sun’ position, so that the upper half of the pylorus is visible at the 6 o’clock position. Check that the shaft of the scope is at the 12 o’clock position when intubating the pylorus as this ensures optimum positioning in front of the papilla. The duodenoscope is then inserted into the second part of the duodenum. Two maneuvers are performed in succession: first turn the big wheel anticlockwise and the small wheel clockwise, thus deflecting the tip of the scope up and right, then withdraw the endoscope to 50–70 cm from the incisors to reduce the gastric loop.




    Figure 1


    Inserting the duodenoscope and positioning over the papilla. (A) Duodenoscope advancing blind into the esophagus. (B) Advancing along the lesser curvature. (C) The endoscope rests on the greater curvature and faces the pylorus. (D) Deflection upwards, before advancing through the pylorus. (E) The apparatus advances to the superior flexure. (F) The endoscopist turns to his right through 90°. (G) The endoscopist has turned to his right through 90°. (H) Deflection upwards and to the right by turning the small wheel clockwise and the big wheel anti-clockwise. (I) Withdrawal of the endoscope to approximately 70 cm which removes the gastric loop.



    Problems with intubation





    • Unable to intubate the esophagus:




      • STOP. DO NOT PUSH. Withdraw the duodenoscope and insert a forward-viewing scope to exclude a pharyngeal pouch or stricture. A guidewire can be left in the stomach to guide insertion with the duodenoscope if required.




    • The duodenoscope coils in the fundus:




      • Ensure the patient is fully in the left lateral decubitus position. If necessary, place a bolster under the patient. Withdraw to the cardia then deflect slightly to the right after advancing through the cardia once again. Follow the vertical folds along the lesser curvature to the pylorus.



      • Avoid over-inflating the stomach.




    • The duodenoscope advances as far as the superior flexure of the duodenum facing upwards:




      • Rotate the scope to the right through 90°, by turning from facing the patient to facing the monitor video and be perpendicular to the patient ( Fig. 7 ) patient. This will present the second part of the duodenum.




        Figure 7


        Cannulation of the bile duct. The bile duct is cannulated going from inferior to superior while directing the catheter towards 11 o’clock. The pancreatic duct is cannulated in an en face position, directing the catheter from left to right and towards 1 o’clock.




    Box 1

    Short versus long scope position





    • In a short scope position, the duodenoscope is straight with no gastric loop, and is normally between 50 and 70 cm from the incisors.



    • In the long scope, a gastric loop is left in the stomach with 70+ cm of the duodenoscope inserted.





    Locating the papilla


    The major papilla should now be in the field of vision. The major papilla consists of a frenulum, a hood, infundibulum, and orifice ( Fig. 2 ). It is often a different color from the rest of the duodenum. The papilla should be inspected for evidence of stone passage (gaping or inflamed orifice), edema or papillary adenoma. The major papilla is then classified depending on its appearance ( Fig. 3 ). This is important when assessing how far a sphincterotomy may be extended and to do a diathermic puncture of biliary infundibulum.




    Figure 2


    Normal papilla. (1) Papillary orifice. (2) Frenulum. (3) Hood. (4) Infundibulum.



    Figure 3


    Classification of the various types of infundibulum. Type 0: no infundibulum. Type 1: the infundibulum extends to the limit of visibility. Type 2: a prominent infundibulum. Type 3: a large infundibulum which covers the papilla.



    Problems identifying the major papilla


    The papilla is normally found on the medial wall of the duodenum, but can be located anywhere from the duodenal bulb to the mid-descending duodenum. If the papilla is not visible after performing the maneuvers described above, the following should be tried:




    • Wait a little before changing position



    • Improve visualization with antifoam solution (i.e. simethicone)



    • Give glucagon to decrease duodenal motility



    • Search for the papilla by gently lifting the mucosal folds with a catheter and look for the frenulum, infundibulum, or hood



    • There is usually only one longitudinal fold in the second part of the duodenum – the major papilla is usually located at the end of this fold. This is often described as having a ‘neck tie’ appearance ( Fig. 4 )




      Figure 4


      Neck tie appearance of the major papilla (arrow).



    • Occasionally, the papilla is located in the third part of the duodenum. This can be reached using the long scope position (>70 cm)



    • The infundibulum can be divided into four types (Type 0–3; Fig. 3 ). This system is useful if a pre-cut sphincterotomy is required. A Type 0 infundibulum is not suitable for pre-cut, while Types 2 or 3 have the ideal configuration for pre-cut sphincterotomy.



    In cases where there is difficulty identifying the major papilla, look for the ‘neck tie’ appearance with a longitudinal fold ( Fig. 4 ) in the second part of the duodenum.



    Locating the minor papilla


    The minor papilla is smaller ( Fig. 5 ), and is usually located 2 cm proximal and anterior to the major papilla in the second part of the duodenum. It can be difficult to locate. In these cases consider the following:




    • Use a long scope position: this is usually the optimum position to see the minor papilla



    • Place the patient in the supine position



    • Give secretin. Some authors recommend spraying the second portion of the duodenum prior to giving secretin.




    Figure 5


    Minor papilla (arrow).



    Cannulating the major papilla


    Flush the catheter or sphincterotome with dye prior to commencing the procedure to prevent any injection of air. Prior to attempting cannulation, optimize conditions and ensure there is an adequate view of the papilla by ensuring:




    • Duodenal hypotonia: give glucagon if necessary



    • No bubbles or mucus: use antifoam solution (simethicone)



    • Take time to optimally position the duodenoscope and ensure that the orifice is at the center of the image



    • Wait a little for the orifice to open.




    Cannulating the bile duct and pancreatic duct


    To selectively cannulate the bile duct, the side-viewing duodenoscope should be placed below the major papilla. Place the catheter slightly below the papilla and direct the catheter vertically towards 11–12 o’clock ( Fig. 6 ) in the right upper quadrant. Cannulation of the pancreatic duct requires the duodenoscope to be placed en-face , and slightly to the left of the papilla. The catheter should be placed on the right side of the papilla between 1 and 3 o’clock, with the catheter moving from left to right. If the os is difficult to catheterize, the catheter can initially be introduced a few millimeters, then directed towards the biliary or pancreatic orifice. The catheter is then introduced as far as possible into the chosen duct.




    Figure 6


    Orientation of the pancreatic and bile duct. Using the face of a clock for orientation, the pancreatic duct is found between 1 and 3 o’clock position, while the bile duct is found at 11 o’clock.


    In obese patients, those with malignant pancreatic disease, particularly where there is a lesion in the genu of the pancreas, it can be difficult to properly centre the major papilla. In these cases, a long scope position may be required, and the endoscopist may need to position themselves in the opposite of the classic position (i.e. at 90° to the patient’s face).



    Box 2

    Role of a guidewire





    • A wire allows the sphincterotome to be manipulated (i.e. withdrawn to just above the ampulla) without losing cannulation. This is very useful for people learning ERCP or after a difficult cannulation. It is also useful when the papilla is difficult to cannulate (i.e. stenotic os).



    • It can be useful to determine whether the correct duct has been cannulated, thus avoiding repeated injection of contrast into the pancreatic duct. This is done by looking at the direction the wire follows (see Clinical Tip ‘How do I know which duct I am in’ below).



    • The guidewire is also very useful where minimizing contrast injection is important, e.g. in a patient with cholangiocarcinoma.




    Clinical Tip


    How do I know which duct I am in?





    • Depth of duct cannulation:




      • Deep duct cannulation is usually associated with bile duct cannulation



      • Intermediate duct cannulation usually occurs after cannulating the pancreatic duct as the catheter comes up against the genu of the pancreatic duct.




    • Aspiration:




      • Aspiration of yellow bile or colourless pancreatic juice helps to determine which duct the catheter is in without injecting it.




    • Wire direction:




      • The direction of the guidewire can be used to confirm which duct has been cannulated. The wire should advance towards the diaphragm, moving towards 11 o’clock, when the bile duct is cannulated. The guidewire initially moves towards 1 o’clock followed by the 3 o’clock position if the pancreatic duct is cannulated.






    Failure to cannulate the desired duct





    • Check that the catheter is in the correct orientation to cannulate the desired duct:




      • Use fluoroscopy to check the position of the endoscope and the direction of the catheter. To cannulate the bile duct, check that the tip of the endoscope is slightly under the papillary orifice, with the catheter pointing towards 11 o’clock ( Fig. 7 ). For the pancreatic duct, the tip of the endoscope should be placed in the same area as the papillary orifice, with the catheter directed towards 1–3 o’clock ( Fig. 7 ).




    • The pancreatic and biliary orifices are separate:




      • If the pancreatic duct is repeatedly cannulated, look above the cannulated orifice for the biliary orifice.




    • The catheter is in the correct direction for the bile duct, but deep cannulation cannot be achieved:




      • This is because the catheter is up against the anterior wall of the ampulla or the common bile duct. Withdraw the endoscope slightly: when the papilla has disappeared from the visual field, push the catheter forward into the bile duct.




    • Use a hydrophilic guidewire to cannulate the desired duct ( Fig. 8 ).




      Figure 8


      Selective cannulation with a wire. A wire can be used to selectively cannulate either the bile duct. (A) Note the position of the duodenoscope below the papilla or the pancreatic duct. (B) Once the correct duct has been cannulated with the guidewire, the sphincterotome is then inserted over it.



    • Change the catheter to a sphincterotome:




      • The sphincterotome can be tensed, which allows for maximum elevation to assist biliary cannulation.




    • The papilla is stenotic:




      • A tapered catheter or sphincterotome is sometimes useful.




    • If the pancreatic duct is repeatedly entered, a wire can be left in the pancreatic duct. This prevents further pancreatic duct cannulation. It also identifies the direction of the pancreatic duct. Once this is known, the direction of the bile duct can be determined. Alternatively, a pancreatic duct stent can be inserted, with subsequent cannulation of the common bile duct.



    • Cholecystokinin can sometimes be used. This causes the gallbladder to empty with subsequent opening of the papillary orifice.



    Needle knife pre-cut sphincterotomy should not be used to access the biliary or pancreatic duct, except in an emergency. If the above maneuvers fail, the procedure should be discontinued and a repeat attempt made 24–48 h later. This allows the edema to settle, and the second procedure is often successful.



    Cannulating the papilla beside a diverticulum


    Diverticulae frequently occur in the second part of the duodenum, especially in elderly individuals. In these cases, look for the papilla at the edges or inside the diverticulum ( Fig. 9 ). Occasionally it is hidden by the duodenal folds, which should be lifted using a catheter. If the papilla cannot be identified, identify the frenulum and hence the papilla. Cannulating a papilla located at the edge, inside or in the middle of a diverticulum is usually possible. The difficulty arises when the papilla is located inside the diverticulum and with the os also facing towards the inside of the diverticulum. In these cases, the following can be tried:




    • Evert the papilla by pressing with a catheter on the edge of the diverticulum without insufflating it too much.



    • Saline has been used raise the papilla from the diverticulum ( Fig. 10A,B ); however, this can be associated with pancreatitis.



    • Gently tease the papilla outside the diverticulum with a biopsy forceps ( Fig. 10C ).




      Figure 10


      Techniques for accessing a papilla located within a diverticulum. Saline can be injected (A) which raises the papilla from the diverticulum (B). However, this is associated with an increased risk of pancreatitis. Biopsy forceps can also be used to tease the papilla out of the diverticulum (C).



    • It is sometimes possible to place the tip of the endoscope into the diverticulum to center it.



    • Percutaneous transhepatic wire can be inserted through the ampulla (see section 8.11).




    Figure 9


    Location of papilla in the presence of a diverticulum. The papilla is located at the left (A) or right (B) edge of a large diverticulum. This is the most common presentation. (C) Papilla between two small diverticula. (D) Papilla in the centre of large diverticulum.



    Cannulating a stricture


    Traversing a difficult stricture requires patience, skill and optimum X-ray control. When a difficult stricture is encountered the following should be tried:




    • Consider using a fully hydrophilic wire for difficult strictures ( Fig. 11 ). Also an angled tip is sometimes useful. Repeat forward and back movements while simultaneously twirling the wire. Occasionally, a 0.025 or 0.018 inch guidewire is needed. An ultratapered sphincterotome or cure-tipped 5–6 Fr cannula may also be useful. Once the stricture has been traversed, the sphincterotome is advanced across the stricture and the guidewire should be exchanged for a regular guidewire as this facilitates dilation or stent placement.




      Figure 11


      Inserting a guidewire through a stricture. Strictures should be crossed initially using a guidewire. If the guidewire is hitting the side walls (A,B), withdraw the sphincterotome slightly (C). This maneuver allows optimal alignment of the guidewire with the stricture.



    • The left hepatic duct is usually more difficult to cannulate. Bounce the guidewire off the lateral wall to cannulate the left hepatic duct. A swingtip or Haber Ramp catheter is occasionally useful in difficult cannulation.



    • Cannulate the right hepatic duct by placing the sphincterotome at the level of the bifurcation and direct towards the right hepatic duct.



    • Distortion of the second part of the duodenum by tumour can hinder the correct centering of the papilla. If cannulation of the papilla is difficult, determine if this is a technical problem or a low stenosis. Review pre-ERCP imaging (ideally MRC or EUS) to determine whether there is a low stenosis near the papillary orifice. In this case, use a sphincterotome mounted on a guidewire to find the orifice of the stenosis. Pre-cut sphincterotomy or diathermy loop excision of the infundibulum may be necessary.



    • Make a loop with the guidewire ( Fig. 12 ). Once the loop moves in the desired direction, advance the sphincterotome over the guidewire to the apex of the loop. Then withdraw the guidewire until the wire is straight. Reinsert the guidewire, forming a loop if necessary. This is repeated until the stricture is traversed.




      Figure 12


      How to manipulate the wire into the correct hepatic duct. (A) Produce a loop with the guidewire. (B) Insert the catheter to the end of the loop. (C) Undo the loop formed by the guidewire. (D) Insert the guidewire through the catheter lying in the correct direction. Withdraw the guide catheter to change the direction of the guidewire if the guidewire fails to pass through the stenosis.



    • Advance stepwise if the stenosis has several angulations. The guidewire is advanced to the end of the first angulation ( Fig. 13A ). The sphincterotome is advanced over the guidewire to this point ( Fig. 13B ). The guidewire is advanced to the end of the second angulation, followed by the sphincterotome ( Fig. 13C ). This is repeated until the stricture is crossed ( Fig. 13D ).




      Figure 13


      Inserting a guidewire through a complex stricture. The guidewire is advanced in a stepwise manner. The guidewire is advanced to the end of the first angulation (A). The sphincterotome is advanced over the guidewire to this point (B). The guidewire is advanced to the end of the second angulation, followed by the sphincterotome (C). This is repeated until the stricture is crossed (D).



    • Changing the patient position can help. For complex hilar strictures, placing the patient in the dorsal decubitus position is often useful.



    • Placing an inflated retrieval balloon below the stricture can stretch the bile duct and alter the angle aiding guidewire cannulation.




    Cannulating the minor papilla


    The accessory or minor papilla is usually located 2 cm proximal and anterior to the major papilla in the second part of the duodenum. The os is often very small (2 mm), with the duct of Santorini running from the 5 o’clock to the 11 o’clock position. The easiest position to cannulate the minor papilla is in the ‘long’ scope position, with the patient supine. Patience is essential. Wait for the orifice to open before attempting cannulation. Cannulation is usually performed initially with wire, following with the sphincterotome once the duct has been cannulated. This is usually possible with a regular sphincterotome, however a tapered sphincterotome can be required if the os is very small or stenosed. Care should be taken to avoid submucosal injection. If the minor papilla is difficult to locate or cannulate, placing the patient in the supine position is often useful helpful. Secretin can be used to aid identification and to encourage the os to open.



    ERCP in patients with altered anatomy



    Post-surgical anastomoses


    Performing ERCPs in patients who have undergone gastroenteric anastomoses is becoming increasingly common as more patients undergo gastric bypass surgery for obesity. It is important to know what type of surgery has been performed before commencing the ERCP, as this will determine the type of endoscope used, as well as the difficulty of the procedure. Some of these procedures, such as post-duodenopancreatectomy (Whipple’s) are technically demanding, and are often best referred to a tertiary referral centres.



    Which endoscope to use?


    A duodenoscope is usually used where possible, as the presence of the elevator facilitates cannulation. In addition, the side viewing assists location of the ampulla ( Fig. 14A ). However, it is sometimes not possible to reach the papillary area due to the length of the afferent loop. In these cases, a forward viewing scope should be used. Reaching the ampulla is often successful with a forward viewing scope; however, the ampulla can be more difficult to visualize ( Fig. 14B ), and the lack of an elevator can make cannulation or exchanging over a guidewire difficult. The choice of forward viewing scope depends on what is available in the unit and the experience of the endoscopist. Options include a pediatric colonoscope, a single or double balloon enteroscope, or an enteroscope with Spirus overtube. Where a forward-viewing endoscope is used, but cannulation has failed, it is possible to leave a wire and then backload this wire onto a duodenoscope.




    Figure 14


    View of the ampulla in a patient with altered anatomy with a duodenoscope or forward viewing scope. In patients with altered anatomy, the ampulla can be reached with a duodenoscope or a forward viewing endoscope. The duodenoscope is side viewing and allows good visualization of the ampulla (A). The ampulla can be slightly more difficult to visualize with a forward viewing endoscope (B).



    Pyloroplasty and Billroth I surgery


    The major papilla can be reached with a duodenoscope, and the common bile duct or pancreatic duct is cannulated as normal.



    Gastroenteric anastomosis with a preserved pylorus


    In cases of gastroenteric anastomosis, a duodenoscope can be used if the pylorus is patent. However, the pylorus often becomes stenosed. In these cases, the afferent loop should be used to access the papilla.



    Choledochoduodenal anastomosis


    For patients with a choledochoduodenal anastomosis ( Fig. 15A ), a forward-viewing endoscope is sometimes required. The anastomosis is usually located on the anterior side of the bulb. If the anastomosis is patent, the endoscope can be introduced into the bile duct. If it is an end-to-side choledochoduodenal anastomosis ( Fig. 15B ), i.e. if the segment underlying the anastomosis is closed, access to the papilla should be gained using a duodenoscope.



    Clinical Tip


    Sump syndrome


    ‘Sump syndrome’ is a rare complication of a side-to-side choledochoduodenostomy ( Fig. 15A ). The common bile duct between the anastomosis and the ampulla of Vater acts as a reservoir in which debris and stones collect. This can result in abdominal pain, cholangitis, biliary obstruction or pancreatitis. ERCP findings include dilated bile or pancreatic duct, and signs of chronic pancreatitis.




    Figure 15


    Choledochoduodenal anastomosis. (A) A side-to-side choledochoduodenal anastomosis. (B) An end-to-side choledochoduodenal anastomosis.



    Pancreaticoduodenectomy (Whipple’s)


    The classic pancreaticoduodenectomy described by Whipple consists of removal of the pancreatic head, duodenum, first 15 cm of the jejunum, common bile duct, and gallbladder, as well as a partial gastrectomy ( Fig. 16 ). There is a side-to-side gastrojejunostomy, often with a long afferent loop and a variety of placements for the pancreatico- and hepatico-jejunostomies. In a pylorus preserving pancreaticoduodenectomy, the gastric antrum, pylorus, and proximal 3–6 cm of the duodenum are preserved, with an end-to-side pylorojejunostomy. The pancreaticojejunostomy is usually located at the apex of the loop, with the hepatic-jejunotomy about half way down the afferent loop. In these patients, pancreatic and biliary anastomoses can rarely be reached with a duodenoscope and a forward viewing endoscope should be used.



    Box 3

    The afferent loop


    How to identify and enter the afferent loop





    • The afferent loop is almost always more difficult to access than the efferent loop.



    • The afferent loop is usually adjacent to the lesser curve.



    • If it is not possible to intubate the afferent loop, place the patient to prone or supine position.



    • A wire can be advanced into the correct loop, and the endoscope guided over the wire into the loop.



    • If this fails, a CRE wire-guided balloon is sometimes useful. It can be inflated in the loop, and the endoscope then guided into the loop. These procedures should be performed under fluoroscopic guidance to avoid complications.



    How do I know if I am in the afferent loop?


    There are several tools you can use to determine if the endoscope is in the correct limb:




    • Use fluoroscope to confirm that the endoscope is moving towards the right hypochondrium.



    • The presence of bile.





    Figure 16


    Classic Whipple. This is a non-pylorus preserving pancreaticoduodenectomy. The head of the pancreas has been resected. There is a gastrojejunostomy, with an afferent and efferent limb. The afferent limb leads to the hepatico- and pancreaticojejunostomies. Note that the pancreaticojejunostomy is past the hepaticojejunostomy and is often found almost at the end of the afferent limb.



    Gastrojejunal anastomosis (Billroth II)


    A Billroth II was often performed in patients with peptic ulcer disease or gastric antral carcinoma and consists of a partial gastrectomy with end-to-side gastrojejunostomy ( Fig. 17 ). The operation may also be known as a Polya and Hoffmeister, depending on how the gastrojejunostomy is performed. A duodenoscope should be used initially. If this is unsuccessful, it can be exchanged for a forward viewing endoscope. There is a native papilla, but the pancreatico-biliary anatomy is reversed as described in the pancreaticoduodenectomy.



    Box 4

    Jejunojejunal anastomoses





    • Enteric anastomoses can either be in the ‘Y’ configuration, which presents the endoscopist with two lumens to choose from, or in a side-to-side anastomosis, which appears as three lumens.



    • The afferent loop is usually the most difficult loop to enter.





    Figure 17


    Gastrojejunal anastomosis. (A) Demonstrates the relationship of the afferent and efferent limbs in a gastrojejunal anastomosis (Finisterer type procedure). (B) Note the location of the afferent loop – it is at the top left under the fold and is the more difficult limb to enter.



    Gastric bypass surgery


    There are two types of gastric bypass surgery performed. In patients with gastric outlet obstruction, a side-to-side loop gastrojejunostomy is performed. Patients undergoing gastric bypass surgery as a treatment of obesity often have a gastric pouch which is separated from the rest of the stomach. The pouch empties into an end-to-side gastrojejunostomy. A jejunojejunostomy connects the other part of the stomach, duodenum and jejunum in a Roux-en-Y configuration. Although it is occasionally possible to reach the anastomosis with a duodenoscope, a forward viewing endoscope is usually required. There is a native papilla, but as with a Billroth II or pancreaticoduodenectomy, the anatomy is reversed with the bile duct between 5 and 6 o’clock.



    Box 5

    How to reach the papilla in a patient with an afferent limb





    • The afferent limb should be approached in a similar manner to a colonoscopy, with repeated shortening of the endoscope and removal of loops.



    • Contrast can be injected either through a catheter or a CRE balloon (if reflux of contrast is a problem). This is useful where there are sharp angulations to determine the direction of the afferent loop.



    • External manual compression can be useful.



    • Take care not to stretch the anastomosis, as perforation can occur.





    Cannulating the bile duct and pancreatic duct in patients with Billroth II or Whipple’s procedure


    In Billroth II the ampulla will be intact, while in a Whipple’s or other reconstructive surgery there will be a surgical anastomosis (i.e. choledochoenteric anastomosis), and the pancreatic and bile duct anastomoses are usually found separately in the jejunum. The pancreatic duct is often located just proximal to the end of the loop, while the biliary orifice is located proximal to the pancreatic orifice, on the anti-mesenteric wall. As the papilla has been reached retrograde through the afferent loop, the anatomy is reversed by 180° with the biliary orifice found between 5 and 6 o’clock rather than the normal 11 o’clock position ( Fig. 18 ). A straight catheter can be used to cannulate the bile duct or pancreatic duct. It is helpful to maintain an en-face position and exaggerated distance away from the ampulla. A standard cannula is sometimes useful, as a standard sphincterotome may make biliary cannulation difficult in this situation due to its pre-curve. In our experience, guidewire cannulation is particularly useful in these circumstances.




    Figure 18


    Cannulating the papilla in a patient with a Billroth II. As the papilla has been reached retrograde through the afferent loop, the anatomy is reversed by 180° with the biliary orifice found between 5 and 6 o’clock rather than the normal 11 o’clock position.



    Rendezvous procedure


    A percutaneous transhepatic catheter (PTC) is inserted by an interventional radiologist prior to or at the same time as the ERCP.


    Technique





    • Identify the percutaneous catheter ( Fig. 19 )




      Figure 19


      Rendezvous procedure. (A) A PTC catheter is inserted by an interventional radiologist. (B) The catheter is identified. (C) The sphincterotome is advanced in the catheter. Once percutaneous catheter containing the sphincterotome is retracted into the bile duct, the PTC catheter is withdrawn. (D) Biliary sphincterotomy is performed.



    • Insert a sphincterotome into the catheter



    • The percutaneous catheter containing the sphincterotome is retracted into the bile duct



    • The sphincterotome is placed in the papilla and a standard sphincterotomy performed.



    Alternative techniques





    • Use the PTC catheter as a guide, and cannulate alongside the catheter using a sphincterotome with a wire.



    • A guidewire is inserted percutaneously ( Fig. 20 ). The guidewire is retrieved using a snare and gently pulled into the instrument channel. A sphincterotome is then inserted over the guidewire and a standard sphincterotomy is performed.




      Figure 20


      Rendezvous procedure. (A) Percutaneous insertion of a guidewire through the papilla. (B) Retrieval of the guidewire using a snare which is re-inserted in the operating channel. (C) A sphincterotome is inserted over the guidewire. (D) Biliary sphincterotomy is performed.



    • A variation of this is where a catheter has been placed by radiology. Insert a guidewire through the catheter ( Fig. 21 ). The percutaneous guidewire is retrieved using a snare and pulled out of the instrument channel. The guide catheter is mounted on the guide wire in the bile duct. The stent is pushed through the stenosis.




      Figure 21


      Alternative rendezvous technique for access to the papilla. (A) The percutaneous guidewire is recovered using a diathermy loop. (B) The guide catheter is mounted on the guidewire in the bile duct. (C) The stent is pushed through the stenosis. (D) Withdrawal of the guidewire before withdrawal of the catheters. (E) Stent in the hepatic parenchyma to be repositioned.



    Warning!!


    It is very important to work closely with radiology. Large catheters should not be removed without prior discussion with radiology, as these can cause bile to leak into the peritoneum.



    Clinical tips for patients with a PTC





    • If the sphincterotome is being advanced over the wire, a long wire (>450 cm) is required as it will need to pass from the liver, through the duodenoscope.



    • Always manipulate the catheter/wire gently as liver laceration can occur.



    • Some of the PTC catheters have a fixed pigtail to maintain their position in the duodenum. This must be either released or cut prior to removing the catheter or liver laceration can occur.



    • It is advisable to insert a regular guidewire through the PTC catheter prior to manipulating it to minimize the risk of laceration.



    PTC, percutaneous transhepatic cholangiogram.




    Successful cannulation rate


    Cannulation of the papilla is successful in 95–98% of cases when performed by an experienced endoscopist. The pancreatic ducts are opacified on average in 90–95% of cases and the bile ducts in 85–90%. Failures are due to duodenal stenosis, a papillary lesion, or the intradiverticular location of the papilla.


    In patients with altered anatomy, success rates depend on the type of surgery. Patients with a pyloroplasty, Billroth I, or choledochoduodenal anastomosis, have a similar success rate to normal ERCP. Patients with a Roux-en-Y have lower success rates of between 60% and 75%, provided the afferent loop is not too long or located transmesocolically.



    ERCP in children


    ERCP in children should be undertaken under general anesthesia. A diagnostic side-viewing duodenoscope may be used from the age of 1 year upwards. A therapeutic duodenoscope can be used in children over 5 foot. A 7.5 mm diameter duodenoscope with a 2.0 mm operating channel is available for use in children under the age of 1. There are few indications: bile duct stones, jaundice due to bile duct malformation, recurrent pancreatitis, pancreatic trauma, bile stones.





    Cytology, biopsies, and biochemical analysis





    • Summary


    • 1

      Cytology 391


    • 2

      Biopsies 391


    • 3

      Brushing 391


    • 4

      Biochemical examination of bile and pancreatic juice 391



    Key Points





    • Cytological analysis of bile and pancreatic juice have a sensitivity of between 35% and 70% and specificity of >90% for the diagnosis of cancer.



    • Biopsies of the major papilla should be taken in all patients suspected of having autoimmune pancreatitis.



    • Transpapillary biopsies can be performed following biliary sphincterotomy and have a similar sensitivity and specificity as cytology.



    • The type of tumor and the number of passes made with a brush affect the sensitivity. Multiple passes should be made in a patient with a suspicious lesion.





    Cytology


    The cytological study of the bile or pancreatic juice can help to diagnose cancer of the bile ducts or pancreas and has a sensitivity of between 35% and 70%, with a specificity of >90%. Fluid can be collected by selective catheterization, or by collection of duodenal aspiration either after irrigation with saline or following stimulation with either CCK or secretin. Stents inserted into potentially neoplastic stricture should also be sent for cytological analysis.



    Biopsies


    Endoscopic transpapillary biopsies of a localized lesion or stenosis of the biliary or pancreatic ducts are more difficult, with a sensitivity of between 43% and 88% and a specificity of >90%. It is particularly difficult to introduce biopsy forceps through an intact papilla and to position them correctly within the lesion. Biopsies of the major papilla should be taken in patients who are suspected of having autoimmune pancreatitis.



    Brushing


    The sensitivity of endoscopic transpapillary brush cytology is dependent on the type of tumor, as well as the number of passes made with the brush. Thus, it is important to brush multiple times, and to repeat brushing if the patient returns for repeat ERCP. Tumors which compress the bile duct (i.e. pancreatic) have a lower sensitivity than primary biliary cancer. If a pancreatic neoplasm is suspected, endoscopic ultrasound should be considered as the initial procedure of choice to obtain tissue.


    A new technique, inserting a guidewire through a stricture and collecting juice above the stricture, has a high sensitivity (93%) and specificity (100%) in a single study. Further studies are required to confirm these promising results.



    Biochemical examination of bile and pancreatic juice



    Collection of bile juice


    The biochemical study of bile should be carried out before contrast is injected. Optimal collection requires deep biliary cannulation with a catheter with three lateral holes in its tip. The collection of pure bile samples is indicated in three circumstances:




    • Severe cholangitis: Samples should be sent for culture and antibiotic sensitivity test



    • Testing for lithogenic bile: Calcium bilirubinate crystals, bile pigments and cholesterol ( Fig. 1 ) can be seen. This is used if microlithiasis is suspected in patients who have pancreatic or biliary clinical symptoms, and can be treated with ursodeoxycholic acid




      Figure 1


      Crystallography of bile. (A) Calcium bilirubinate crystals. (B) Bile pigments. (C) Cholesterol crystals (translucent, larger) and calcium bilirubinate crystals (yellow and brown) obtained by bile sampling.



    • Pharmacokinetic study of drugs eliminated via the bile in relation to hepatobiliary disease.




    Collection of pancreatic juice


    Pure pancreatic juice can be collected for analysis of molecular markers as part of a research study. Pancreatic juice can also be collected after stimulation with secretin.





    Pancreaticobiliary anatomy





    • Summary


    • 1

      Normal and variant biliary anatomy 393


    • 2

      Post-surgical anatomy 398



    Key Points





    • Understanding normal, variant and post-surgical pancreaticobiliary anatomy is essential.



    • The Couinaud classification divides the liver into eight functionally independent segments.



    • The most common variation of biliary anatomy is where the right posterior hepatic duct drains into the left hepatic duct, prior to its confluence with the right anterior hepatic duct.



    • In patients undergoing laparoscopic cholecystectomy, surgeons should be informed of altered cystic duct anatomy.



    • Pancreas divisum is the embryonic anomaly most commonly found in adults (5% of ERCP), characterized by the failure of the ventral and dorsal pancreatic ducts to fuse.





    Normal and variant biliary anatomy


    The Couinaud classification gives eight functionally independent segments, numbered I through VIII ( Fig. 1 ). The segments are numbered in a clockwise manner starting with the caudate lobe (segment I). Each segment has its own vascular inflow, outflow, and biliary drainage. In the center of each segment there is a branch of the portal vein, hepatic artery, and bile duct. In the periphery of each segment, there is vascular outflow through the hepatic veins. The liver is divided by vascular structures. The right hepatic vein divides the right lobe into anterior and posterior segments. The middle hepatic vein divides the liver into right and left lobes, while the left hepatic vein divides the left lobe into medial and lateral parts. The portal vein divides the liver into upper and lower segments.




    Figure 1


    Normal segmental anatomy of the liver. This drawing shows normal biliary segmental anatomy, which is observed in 56% of individuals.


    The biliary drainage runs in parallel to the portal venous supply. The right hepatic duct drains the segments of the right liver (V–VIII), with the right posterior duct draining the posterior segment (VI and VII), and the right anterior duct draining the anterior segments (V, VIII). The right posterior duct has an almost horizontal course, while the right anterior duct tends to have a more vertical course. The left hepatic duct is formed from tributaries draining segments II–IV. The common hepatic duct is formed by fusion of the right and left hepatic ducts. The duct draining the caudate lobe (I) usually joins the origin of the right or left hepatic duct. The cyst duct usually joins the common hepatic duct below the confluence of the right and left hepatic ducts ( Fig. 2 ).




    Figure 2


    Extrahepatic biliary tree.


    There are variations of this classic anatomy. The most common variant, which is present in up to 19% of the population, is where the right posterior duct drains into the left hepatic duct before its confluence with the right anterior duct ( Fig. 3D ). Another common variant, occurring in 12% of individuals, is where the right posterior duct empties into the right aspect of the right anterior duct. Another common variant is where the right anterior, posterior, and left hepatic ducts drain simultaneously into the common hepatic duct ( Fig. 3A ). In these individuals, the right hepatic duct is virtually non-existent.



    Note


    ERCP images can only be interpreted with the patient in dorsal decubitus position.




    Figure 3


    Hepatic duct variation. Variant anatomy most commonly affects the right hepatic duct. (A) The right posterior (RP), right anterior (RA) and left hepatic duct (LHD) insert together. This occurs in 12% of individuals. (B) Segments II, III and IV join the right anterior and posterior ducts in 3% of people. (C) This is the most common anatomical variation, occurring in 16% of individuals, where the right anterior hepatic duct (RA) drains into the left hepatic duct (LHD), prior to its confluence with the right posterior hepatic duct (RP). Other variations include insertion of the left hepatic duct into the right posterior hepatic duct, prior to insertion of the right anterior hepatic duct (4%) (D); insertion of the right anterior hepatic duct into the left hepatic duct followed by a confluence with the right posterior hepatic duct (5%) (E); insertion of the right posterior hepatic duct into the left hepatic duct which then joins the right anterior hepatic duct (1%) (F); and (G) confluence of the left hepatic duct with the right posterior hepatic duct which then join the right anterior hepatic duct (1–2%).


    The cystic duct termination exhibits a number of variants. A common variation is where there is a low insertion of the cystic duct into the distal third of the common bile duct (9%) ( Fig. 4 ). Another variation is where the cystic duct drains into the left side of the common hepatic duct.




    Figure 4


    Variations in cystic ductal anatomy. The cystic duct termination exhibits a number of variants. A common variation is where there is a low insertion of the cystic duct into the distal third of the common bile duct (9%) (C). Another variation is where the cystic duct drains into the left side of the common hepatic duct (D).


    The common bile duct terminates at the ampulla of Vater, where it joins the main pancreatic duct (Wirsung’s duct) ( Fig. 5 ). There are a number of variations in the communication between the common bile duct and Wirsung’s duct. It is important to be familiar with these variations when cannulating the papilla ( Fig. 6 ). In the majority of cases (98%), the papilla has a single orifice (type I). The biliary duct and the pancreatic duct may have separate openings in the papilla (type II) ( Fig. 7 ) or openings at different points in the duodenum (type III). There are two types of common opening (or common channel):




    • Type 1a corresponds to a long common channel with extraduodenal confluence of the two channels ( Fig. 8 ).




      Figure 8


      Type 1a common channel. These images illustrate a type 1a, with a long common channel (arrow).



    • Type 1b corresponds to a common channel confined to the mucosa and to the duodenal submucosa.




    Figure 5


    Ampulla of Vater with junction of the common bile duct and Wirsung’s duct. (1) Common sphincter. (2) Choledochic sphincter. (3) Wirsung’s duct sphincter.



    Figure 6


    Variations in the communication between the common bile duct and Wirsung’s duct. Type 1a has a long common bile duct (>1 cm) with one orifice. Type 1b has a short common bile duct with one orifice. Type 2 has a separate orifice for the bile and pancreatic ducts. Type 3 has separate orifices for the bile and pancreatic ducts at different points in the duodenum.



    Figure 7


    Type II opening with separate pancreatic (black arrow) and bile ducts.


    When the common channel is >15 mm long, the frequency of congenital anomalies of the bile ducts (choledochal cyst, Caroli disease) and cholangiocarcinoma is believed to be higher.


    The arterial supply of the papilla exhibits numerous anatomical variations, which are determined by the retroduodenal artery and the branch of the upper pancreaticoduodenal artery. Significant bleeding can occur depending on the configuration of the blood vessels at the papilla ( Fig. 9 ).




    Figure 9


    Arterial supply of the papilla. (A) This configuration is associated with a low hemorrhagic risk with sphincterotomy. (B) This configuration is associated with increased risk of bleeding due to a low arterial trunk which can be cut during sphincterotomy.



    Normal pancreas and its variants


    The main pancreatic duct rises steeply in the head, then crosses the upper abdomen horizontally or in a slightly ascending manner ( Fig. 10 ). In healthy individuals, the shape of the pancreatic duct is variable, and diagnostic conclusions cannot be based on shape alone. Loops (ansa loops) may be observed, particularly in the isthmus ( Fig. 11 ). The diameter of the pancreatic duct is on average 4 mm in the head of the pancreas, 3 mm in the body and 2 mm in the tail. The duct of Santorini usually connects the pancreatic duct to the accessory papilla. Collateral branches open perpendicular to the axis of the pancreatic duct. Their normal diameter should not exceed 1 mm. The diameter of the pancreatic duct increases with age. The aging of the pancreas is accompanied by irregularities in ductal diameter and may make differential diagnosis with incipient chronic calcifying pancreatitis difficult.




    Figure 10


    Normal pancreatic ductal anatomy. (1) Duct of Wirsung or pancreatic duct. (2) Duct of Santorini. (3) Secondary ducts. (4) Parenchyma.



    Figure 11


    Ansa pancreatica loop. A wire is in the pancreatic duct. Note where the tip of the sphincterotome is (arrow) there is an alfa loop consistent with ansa pancreatica but the wire is in the direction of the common bile duct. Ensure careful injection.



    Congenital anomalies of the pancreatic ducts


    Annular pancreas is characterized by a ring of pancreatic tissue surrounding the descending portion of the duodenum. It is thought to be due to incomplete rotation of the pancreatic ventral bud. It is a rare anomaly in adults (0.1% of ERCP).


    Pancreas divisum ( Fig. 12 ) is the embryonic anomaly most commonly found in adults (5% of ERCP), characterized by the failure of the ventral and dorsal pancreatic ducts to fuse. A definite diagnosis can be obtained only by cannulation of the major papilla and the accessory (minor) papilla.




    Figure 12


    Normal pancreatogram and pancreas divisum. (A) Normal pancreatogram. (B) Ventral duct (pancreas divisum). (C) Dorsal duct (pancreas divisum).


    Cannulation of the major papilla opacifies the ventral pancreas ( Fig. 12B ). The ventral duct is short with a small diameter. The length varies from a few millimetres to 5 or 7 cm. If the duct is very short, injection of contrast medium results very quickly in acinarization, which must not be confused with a submucosal injection. If the duct measures 3 or 4 cm, complete occlusion of the head of the pancreas by cancer must be excluded. Opacification of the dorsal pancreas ( Fig. 12C ) should be performed to confirm the diagnosis of pancreas divisum if the ventral pancreas is completely atrophic and invisible after catheterization of the major papilla. Opacification also allows visualization of lesions in the dorsal pancreas. Incomplete forms of pancreas divisum exist ( Fig. 13 ).




    Figure 13


    Variations in pancreatic anatomy.



    Post-surgical anatomy


    It is important to understand post surgical anatomy (see also Ch. 10.6 ), as it is encountered frequently due to the increase in obesity and gastric bypass surgery. Gastroduodenal anastomoses ( Fig. 14 ) and certain types of choledochoduodenal anastomoses ( Fig. 15 ) can usually be reached with a duodenoscope. The papilla is more difficult to reach in patients with Roux-en-Y anatomy ( Fig. 16 ). A pediatric colonoscope, enteroscope or double/single balloon or spiral enteroscopy may be required to reach the papilla. The main problem in these patients is the length of small bowel that has to be traversed. The shortest distance is encountered with a Billroth II ( Fig. 17 ), with the longest distance typically associated with Roux-en-Y, associated with gastric bypass. Whether the limb has been placed antero- or retrocolic can also affect the ability to reach the papilla ( Fig. 18 ). Retrocolic is associated with acute turns which can be difficult to negotiate but it’s a short way to find papilla. Anterocolic is a long way to reach papilla.



    Box 1

    Problematic surgical anatomy





    • Partial gastrectomy with Billroth II gastrojejunostomy.



    • Whipple resection with Roux-en-Y limb of jejunum anastomosed to the biliary and pancreatic ducts.



    • Pylorus preserving Whipple resection with Roux limb of jejunum anastomosed to the duodenal cap.



    • Gastrojejunal bypass for obesity with a Roux limb of jejunum anastomosed to a small gastric pouch.



    • Resection of the bile duct with anastomosis of the common hepatic duct (choledochojejunostomy) or hilum (hepatico-jejunostomy) to a Roux-en-Y limb of jejunum.



    • Biliary diversion procedure with a Roux limb of jejunum draining the gastric remnant after partial gastrectomy.



    • Total gastrectomy with anastomosis of the esophagus to a Roux limb of jejunum.



    From Haber GB. Double balloon endoscopy for pancreatic and biliary access in altered anatomy (with videos). Gastrointest Endosc 66(3 Suppl):S47–S50, 2007.



    Figure 14


    Gastroduodenal anastomoses. (A,B) represent two different types of gastroduodenal anastomoses. A Pean (A) anastomosis is commonly found in Europe, while a Billroth I is seen more frequently in the USA (B). These types of surgery were often performed for treatment of peptic ulcer disease and are seen less frequently now due to eradication of H. pylori and use of proton pump inhibitors.



    Figure 15


    Choledochoduodenal anastomoses. (A) Side-to-side choledochoduodenal anastomosis. (B) End to side choledochoduodenal anastomosis. (C) Choledochojejeunal anastomosis with Roux-en-Y anastomosis.



    Figure 16


    Roux-en-Y. This is the classic Roux-en-Y configuration found in patients with Billroth II, Finsterer and Polya anatomy. Note that the Roux limb can be either antero- or retrocolic (as found in this figure). Retrocolic Roux limbs have greater angulation and can be more difficult to traverse.



    Figure 17


    Gastrojejunal anastomoses. These figures represent different types of gastrojejunal anastomoses. (A) Polya is found more commonly in Europe, while a Billroth II (B) is performed commonly in the UK and USA for patients with pancreatic cancer in the head. (C,D) represent a classic and an isoperistaltic Finsterer gastrojejunostomy. Note that the Roux limbs are labelled A and E. A represents the afferent limb, which contains the papilla or choledochoenterostomy. E is the efferent limb which leads to the remaining small bowel. It is very important to check what limb you are in. This is usually done by looking for bile (afferent limb) and by using fluoroscopy to check your position. The endoscope should be going in the direction of the right upper quadrant. If you are not, you may be in the efferent limb.





    Figure 18


    Roux limbs. In (A) the Roux limbs have been arranged in a classic omega pattern with a side-to-side anastomosis. The omega loop and retrocolic position make it difficult to reach the papilla. The configuration in (B) is better, as there is a relatively straight path to the papilla. (C) Demonstrates enterocolic Roux limb. Patients with this type of anatomy have less angulation of the bowel, compared with retro-colic Roux-limbs; however, the distance to the papilla is greater, which can make accessing the papilla challenging.





    ERCP imaging technique





    • Summary



    • Introduction 400


    • 1

      Dilute or full strength contrast media? 400


    • 2

      How much contrast should be injected? 400


    • 3

      When and how many X-ray images should be taken? 400


    • 4

      Diagnostic problems and interpretation errors 400



    Key Points





    • It is essential that the highest quality radiographic images are obtained during ERCP.



    • Full strength contrast is usually used, unless pancreatic or biliary stones are suspected.



    • Images should be taken from different views to clearly define any abnormal area.



    • Bubbles can be distinguished from stones by placing the patient in the reverse Trendelenburg position.




    Introduction


    It is very important that high quality radiographic images are obtained. The type of contrast used, the amount injected, and how to obtain good radiographic views are discussed below.



    Dilute or full strength contrast media?


    Contrast media can be used undiluted (300 mg iodine/mL), or diluted to 50%. In most cases, undiluted contrast is usually used. This provides excellent visualization of neoplastic stenoses or diseases of the small bile or pancreatic ducts. Diluted contrast is often used where biliary or pancreatic stones are suspected, as stones are often not seen if full strength contrast is used.



    How much contrast should be injected?


    Continue injecting until the intrahepatic bile ducts or the small pancreatic ducts are visible. Do not overfill the gallbladder (due to the risk of cholecystitis) or secondary pancreatic ducts (due to the risk of pancreatitis). Usually 3–5 mL of contrast medium is sufficient to opacify the pancreatic ducts, while 15–20 mL is required for the bile ducts. In patients who have a sphincterotomy, a balloon catheter may be required to allow adequate opacification of the ducts.



    When and how many X-ray images should be taken?


    X-rays should be taken at different stages. An image should be taken before injection and passing the endoscope, as well as in different stages of opacification (as you start injecting, once injection is completed and while contrast is emptying from the ducts). Images taken from different views (left lateral decubitus, dorsal decubitus with slight rotation to the right) can be used to clearly define abnormal areas, and to identify normal structures such as the cystic duct take off. An image of contrast emptying from the bile duct is taken after the duodenoscope has been removed. An image is often taken in the supine position after removing the duodenoscope to exclude perforation for medicolegal reasons. The pancreatic duct, however, empties quickly and images must be taken during the injection of the contrast medium.



    Diagnostic problems and interpretation errors


    Interpreting cholangiographic and pancreatographic images sometimes raises difficult problems, which should be borne in mind.



    Stones or bubbles?


    A filling defect corresponds in the majority of cases to a stone; however, occasionally it may be due to parasites (gallbladder with hydatid cyst, Ascaris , flukes), benign or malignant tumor fragments, hemobilia, or even air bubbles. To differentiate air bubbles from stones, tilt the table in such a way that the patient’s head is elevated (reverse Trendelenburg position). This will cause air bubbles to rise and stones to fall ( Fig. 1 ).




    Figure 1


    Diagnostic dilemmas and interpretation errors. (A,B) Differentiation of a stone versus an air bubble. (A) A possible stone is present in the common bile duct. A stone generally rises towards the intrahepatic bile ducts with a patient prone. (B) Air bubbles do not usually rise. (C) Adenoma arising in the common bile duct appears as a fixed, non-moving object. (D) Hemobilia. (E,F) False underfilling: stone occluding the lower common bile duct (complete filling necessary before drawing conclusions).


    Errors of interpretation can be reduced by some simple principles:




    • Use contrast medium diluted to 75% if stones are suspected.



    • Use undiluted contrast medium if a tumor is suspected (dense bile due to stasis prevents accurate assessment of the limit of the tumor).



    • Catheterization of the bile and pancreatic ducts must be selective and deep to achieve correct opacification which is the key to the correct interpretation of the images.



    • In the left lateral decubitus and ventral position, air bubbles remain in the lower common bile duct, while stones rise to the hilum. In the dorsal decubitus position, the opposite occurs.



    • A close examination of all the images, including those taken in the dorsal decubitus position, is essential. This allows the following to be confirmed:




      • Correct drainage of the bile and pancreatic ducts



      • Opacification of the left intrahepatic bile ducts



      • A stone pushed by the injection into the intrahepatic bile ducts which has re-descended with the patient in dorsal decubitus.




    • The catheter can be connected to a pump which injects contrast. This should be purged correctly with a constant drop-wise injection system to reduce the risk of injecting bubbles. A stone located in the papilla or in the bile duct may simulate the image of a tumor, by its immobility.



    • A stone located in the papilla may not be identified and present a misleading tapered aspect. Images taken during emptying show the normal lower common bile duct with a tapered appearance varying over time, related to the alternate contraction and relaxation of the sphincter of Oddi. A stone or a tumor yields a fixed image.



    • A normal dilated bile duct, without visible stones, does not automatically rule out the possibility of stones. Microlithiasis may be present, the stone may be hidden in contrast medium, or the stone may have migrated since the clinical event.



    • An image in which contrast does not appear to fill beyond the bile duct may correspond to obstruction by a tumor or a false image due to incomplete opacification. This is also true for the left intrahepatic bile ducts, which fill only in excess pressure or in images taken with the patient in dorsal decubitus.



    • The benign or malignant nature of a biliary stenosis is sometimes difficult to determine from the radiological appearance alone.



    • Obstruction of the intrapancreatic bile duct may correspond to cancer of the pancreas or of the common bile duct.



    • Dilation of the bile duct does not always correspond to sphincter of Oddi stenosis, particularly in elderly or cholecystectomized individuals.



    • Cancer in the region of the ampulla of Vater infiltrating the ampulla is not endoscopically visible and may appear as irregular stricture of the lower common bile duct during opacification.



    • Minor anomalies during pancreatography are difficult to interpret. They may correspond to incipient chronic pancreatitis or to a normal pancreas, particularly in the elderly.



    • Compression of bile duct by the gallbladder may be secondary to cholecystitis, a stone impacted in the cystic duct or a tumor lesion (gallbladder cancer).



    • Incomplete stenosis of the pancreatic duct may correspond to cancer or to pancreatitis.



    • Complete stenosis of the pancreatic duct may be due to cancer, pancreatitis or to a technical fault (injection of air bubbles or incomplete opacification which must not be confused with pancreas divisum).



    • Normal pancreatography does not rule out incipient chronic pancreatitis or cancer of the peripheral pancreas.



    • Incorrectly filled intrahepatic bile ducts should be distinguished from sclerosing cholangitis.



    Most of these diagnostic problems can be resolved by correct catheterization technique, rigorous analysis of the radiological images and precise knowledge of the limits of ERCP.




    Abnormal imaging: classification and etiology





    • Summary


    • 1

      Cystic dilation of the bile duct 403


    • 2

      Cholangiocarcinoma 403


    • 3

      Gallbladder cancer 406


    • 4

      Primary sclerosing cholangitis 406


    • 5

      Other causes of biliary dilation 406


    • 6

      Intrahepatic cholestasis 406


    • 7

      Chronic pancreatitis 407


    • 8

      Pancreatic tumors 408



    Key Points





    • A knowledge of abnormal imaging is essential for anyone undertaking ERCP.



    • Hilar cholangiocarcinoma is classified into four types depending on its extent into the intrahepatic biliary tree.



    • Gallbladder cancer can present with Mirizzi’s syndrome.



    • Alternating stricturing and dilation is classic for primary sclerosing cholangitis.





    Cystic dilation of the bile duct


    Congenital cysts of the bile duct are rare. They are classified depending on their location in the biliary tree ( Table 1 , Figs 1–4 ). They can be associated with jaundice, abdominal discomfort, cholelithiasis, cholangitis, hepatic abscesses, recurrent pancreatitis, cirrhosis, portal hypertension, portal vein thrombosis, and are associated with an increased risk of cholangiocarcinoma.



    Table 1

    Classification of congenital bile duct cysts (Todani classification)































    Type of cyst Definition Comment
    I Dilatation of the entire common hepatic or common bile duct or segments of each Account for 80–90% of cysts.
    Treatment of choice is excision of the cyst and Roux-en-Y biliary-enteric anastomosis.
    II Diverticulum in the CBD Surgical excision and primary closure over a T-tube.
    III (choledochocele) There is a dilatation of the intraduodenal portion of the CBD ( Figs 2, 3 ) <3 cm in diameter treat with sphincterotomy.
    ≥3 cm requires surgery.
    IVa Multiple dilatations of the intra- and extrahepatic biliary tree ( Fig. 4 ) Excision of the cyst and Roux-en-Y biliary-enteric anastomosis.
    No specific treatment of intrahepatic cysts.
    If disease is limited to specific intrahepatic segment these can be considered for surgical resection.
    IVb Multiple dilatations of the extrahepatic biliary tree
    V (Caroli disease) Single or multiple intrahepatic cysts If disease is limited to a single hepatic lobe, surgical resection can be considered.
    Transplantation can be considered in patients with decompensated cirrhosis.

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    Mar 5, 2019 | Posted by in GASTOINESTINAL SURGERY | Comments Off on Endoscopic retrograde cholangiopancreatography
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