Endoscopic retrograde cholangiopancreatography (ERCP) is the first-line management in most situations when a benign biliary stricture is suspected. Although management principles are similar in all subgroups, the anticipated response rates, need for ancillary medical and endoscopic approaches, and use of less proven strategies vary between differing causes. Exclusion of malignancy should always be a focus of management. Newer endoscopic techniques such as endoscopic ultrasound, cholangioscopy, confocal endomicroscopy, and metal biliary stenting are increasingly complementing traditional ERCP techniques in achieving long-term sustained stricture resolution. Surgery remains a definitive management alternative when a prolonged trial of endoscopic therapy does not achieve treatment goals.
Video of a plastic biliary stent exchange in a patient with a benign distal biliary stricture secondary to chronic pancreatitis accompanies this article.
- •
Specific techniques including multiple stent placement and the wide use of balloon dilatation have improved outcomes of biliary strictures, but many patients still require definitive surgical therapy for long-term success.
- •
The questions raised in the last 10 years regarding use of self-expandable metal biliary stents (SEMS) in benign disease have not yet been adequately addressed, but this will likely become clearer in the near future.
- •
New covered SEMS designs are awaited, along with the broader use of ancillary devices, including cholangioscopy, endoscopic ultrasound, and confocal microendoscopy, as well as new techniques in cytopathology to definitively exclude malignancy.
- •
Despite its limitations, the safety profile of endoscopic therapy still justifies its place as a first-line management option in benign biliary strictures.
Introduction
Benign biliary strictures arise from a heterogeneous group of disorders with expansive causes, and a variable natural history. Box 1 lists the common causes for benign biliary strictures. Postoperative and inflammatory strictures are the most common. The underlying causal factors usually involve local inflammation or ischemia and secondary fibrosis and scarring. Endoscopic retrograde cholangiopancreatography (ERCP) has usurped surgery as an established first-line diagnostic and therapeutic tool for most presentations of biliary strictures. Despite significant advances in endoscopic techniques and equipment, differentiating malignant from benign strictures can still be challenging; this is particularly relevant for patients with primary sclerosing cholangitis (PSC). In addition, some causes such as chronic pancreatitis remain resistant to endoscopic therapy. This article focuses on the endoscopic management of benign biliary strictures, discusses the general principles, and elaborates on optimal treatment strategies for the more common causes.
Postoperative causes
Cholecystectomy
Hepatic resection
Biliary anastomosis
Liver transplantation
Biliary reconstruction
Biliary: enteric anastomosis
Inflammatory
Chronic pancreatitis and pseudocyst
PSC
Choledocholithiasis
Immunoglobulin (Ig) G4 cholangiopathy
Infections (recurrent bacterial cholangitis, tuberculosis, histoplasmosis, schistosomiasis, human immunodeficiency virus [HIV], parasites)
Postradiation therapy
Other
Ischemic (hypotension, hepatic artery thrombosis, portal biliopathy)
Trauma
Mirizzi syndrome
Postbiliary sphincterotomy
General principles
Diagnosis
Biliary strictures are usually diagnosed based on signs and symptoms of biliary obstruction (abnormal liver function tests, jaundice, abdominal pain, and cholangitis) and evidence of biliary dilatation on imaging. A detailed history to identify risk factors for differing causes should be sought. Localization of the stricture can be guided by cross-axial imaging and identifying a transition point to dilatation. Confirmation of the stricture ultimately depends on cholangiography, either contrast-enhanced or magnetic resonance cholangiopancreatography (MRCP). The modality of imaging used depends on the clinical presentation, the availability and expertise of available investigations at the medical institution, and the clinical suspicion for a stricture at presentation. If a proximal stricture (hilar or intrahepatic ducts) is suspected, cross-axial imaging is preferred before ERCP because other interventions aside from ERCP may be required. For patients with PSC, an MRCP before ERCP is advisable to ensure that instrumentation and subsequent contamination of the biliary tree is appropriate.
Exclude Malignancy
An accurate assessment of the cause and anatomic location of the stricture is critical to gauge success in endoscopic management. Malignancy should always be considered and tissue sampling performed at the initial and subsequent ERCPs. This sampling is usually performed via biliary epithelial tissue brushings or, less commonly, biopsy using a duodenoscope or cholangioscope. The sensitivity and specificity of bile duct brushings ranges from 35% to 70% and 90% respectively. Brushings obtained after dilatation have not consistently been proved to increase yield. Endoscopic ultrasound (EUS) and fine needle aspiration (FNA) are also useful in the evaluation of a biliary stricture as discussed later.
Stricture Characteristics
The location and length of the stricture can be helpful in determining the underlying cause, and guiding the technical considerations of management. Long strictures are more suspicious of a malignant process. Distal biliary strictures can be related to disorders in the pancreatic head. Hilar strictures are concerning for cholangiocarcinoma or an iatrogenic process. Diffuse stricturing and sclerosis is concerning for a systemic inflammatory or infective cause.
Classification
Anatomic classification guides optimal management strategy. Classification systems for benign strictures have been adapted from postoperative stricture findings. The Bismuth classification is the most commonly adapted system used and is based on stricture location and relationship to the confluence. The Bismuth classifications of malignant and benign stricture differ ( Table 1 ). The Strasberg classification ( Table 2 ) is based on location, size, and bile leakage. Hilar and intrahepatic strictures are technically more challenging for the endoscopist, and additional measures including percutaneous transhepatic cholangiography (PTC) may be required for management. In Bismuth IV strictures involving both left and right ducts, endoscopic drainage of both lobes is not always possible. It is critical to ascertain which segments will benefit most from drainage. The right lobe typically drains most of the liver and decompressing the right hepatic duct usually provides more clinical benefit. Assessing for lobar atrophy on imaging may also guide management decisions.
| Classification | Benign Disease | Malignant Disease |
|---|---|---|
| I | Low CHD stricture, >2 cm distal to hilum | Tumor distal to the hepatic confluence |
| II | Proximal CHD stricture, <2 cm distal to hilum | Tumor involving hepatic confluence but preserved left and right duct communication |
| III | Hilar involvement up to proximal extent of CHD, but confluence preserved | Tumor involves CHD with right (IIIa) and left (IIIb) hepatic duct involvement |
| IV | Confluence involved, no communication between left and right ducts | Multicentric with right and left hepatic duct involvement |
| V | Type I, II, or III plus stricture of an isolated (aberrant) right duct | — |
| Class | Injury Type |
|---|---|
| A | Small duct injury in continuity with biliary system, with cystic duct leak |
| B | Injury to sectoral duct with consequent obstruction |
| C | Injury to sectoral duct with consequent bile leak from a duct not in continuity with biliary system |
| D | Injury lateral to extrahepatic ducts |
| E1 | Stricture located >2 cm from bile duct confluence |
| E2 | Stricture located <2 cm from the bile duct confluence |
| E3 | Stricture located at bile duct confluence |
| E4 | Stricture involving right and left bile ducts |
| E5 | Complete occlusion of all bile ducts |
General principles
Diagnosis
Biliary strictures are usually diagnosed based on signs and symptoms of biliary obstruction (abnormal liver function tests, jaundice, abdominal pain, and cholangitis) and evidence of biliary dilatation on imaging. A detailed history to identify risk factors for differing causes should be sought. Localization of the stricture can be guided by cross-axial imaging and identifying a transition point to dilatation. Confirmation of the stricture ultimately depends on cholangiography, either contrast-enhanced or magnetic resonance cholangiopancreatography (MRCP). The modality of imaging used depends on the clinical presentation, the availability and expertise of available investigations at the medical institution, and the clinical suspicion for a stricture at presentation. If a proximal stricture (hilar or intrahepatic ducts) is suspected, cross-axial imaging is preferred before ERCP because other interventions aside from ERCP may be required. For patients with PSC, an MRCP before ERCP is advisable to ensure that instrumentation and subsequent contamination of the biliary tree is appropriate.
Exclude Malignancy
An accurate assessment of the cause and anatomic location of the stricture is critical to gauge success in endoscopic management. Malignancy should always be considered and tissue sampling performed at the initial and subsequent ERCPs. This sampling is usually performed via biliary epithelial tissue brushings or, less commonly, biopsy using a duodenoscope or cholangioscope. The sensitivity and specificity of bile duct brushings ranges from 35% to 70% and 90% respectively. Brushings obtained after dilatation have not consistently been proved to increase yield. Endoscopic ultrasound (EUS) and fine needle aspiration (FNA) are also useful in the evaluation of a biliary stricture as discussed later.
Stricture Characteristics
The location and length of the stricture can be helpful in determining the underlying cause, and guiding the technical considerations of management. Long strictures are more suspicious of a malignant process. Distal biliary strictures can be related to disorders in the pancreatic head. Hilar strictures are concerning for cholangiocarcinoma or an iatrogenic process. Diffuse stricturing and sclerosis is concerning for a systemic inflammatory or infective cause.
Classification
Anatomic classification guides optimal management strategy. Classification systems for benign strictures have been adapted from postoperative stricture findings. The Bismuth classification is the most commonly adapted system used and is based on stricture location and relationship to the confluence. The Bismuth classifications of malignant and benign stricture differ ( Table 1 ). The Strasberg classification ( Table 2 ) is based on location, size, and bile leakage. Hilar and intrahepatic strictures are technically more challenging for the endoscopist, and additional measures including percutaneous transhepatic cholangiography (PTC) may be required for management. In Bismuth IV strictures involving both left and right ducts, endoscopic drainage of both lobes is not always possible. It is critical to ascertain which segments will benefit most from drainage. The right lobe typically drains most of the liver and decompressing the right hepatic duct usually provides more clinical benefit. Assessing for lobar atrophy on imaging may also guide management decisions.
| Classification | Benign Disease | Malignant Disease |
|---|---|---|
| I | Low CHD stricture, >2 cm distal to hilum | Tumor distal to the hepatic confluence |
| II | Proximal CHD stricture, <2 cm distal to hilum | Tumor involving hepatic confluence but preserved left and right duct communication |
| III | Hilar involvement up to proximal extent of CHD, but confluence preserved | Tumor involves CHD with right (IIIa) and left (IIIb) hepatic duct involvement |
| IV | Confluence involved, no communication between left and right ducts | Multicentric with right and left hepatic duct involvement |
| V | Type I, II, or III plus stricture of an isolated (aberrant) right duct | — |
| Class | Injury Type |
|---|---|
| A | Small duct injury in continuity with biliary system, with cystic duct leak |
| B | Injury to sectoral duct with consequent obstruction |
| C | Injury to sectoral duct with consequent bile leak from a duct not in continuity with biliary system |
| D | Injury lateral to extrahepatic ducts |
| E1 | Stricture located >2 cm from bile duct confluence |
| E2 | Stricture located <2 cm from the bile duct confluence |
| E3 | Stricture located at bile duct confluence |
| E4 | Stricture involving right and left bile ducts |
| E5 | Complete occlusion of all bile ducts |
ERCP
Technique
Benign biliary strictures often require multiple endoscopic sessions before complete and sustained resolution is deemed a success or failure. Failure rates are high in particular subgroups. Medical and surgical options should always be considered as adjunct or salvage therapy before and during the course of endoscopic therapy.
From the time a stricture is identified, the primary aims of management include biliary decompression to prevent secondary complications; identification of the underlying cause, with a focus on exclusion of malignancy; and anticipation for adjunct or rescue therapies should endoscopic therapy not succeed. For patients who may require definitive surgical management (liver transplantation, partial hepatectomy, Whipple procedure, or biliary bypass surgery), endoscopic management should be used as bridging therapy and focus should be on optimizing surgical success.
After biliary cannulation is achieved, guidewire choice, the need for dilatation, and stent choice are the 3 main technical decisions to consider. A guidewire should traverse the stricture to secure access, and 1 or several stents placed across the stricture with or without dilatation. Cytology should be obtained to exclude malignancy. In general, the maximum number of stents possible placed side by side should be inserted. A biliary sphincterotomy is recommended to ensure biliary access on subsequent ERCPs. The duration of endoscopic therapy should be 12 months before it is deemed unsuccessful ( Video 1 ).
Guidewire Passage
Guidewires are critical in maintaining biliary access, directing the catheter and stent into the correct segment, and can aid in minimizing contrast contamination of the biliary tree. In a small proportion of patients, it can be difficult to traverse the stricture because of the severity of stenosis. There are many guidewires available with different characteristics, but few comparative studies are available to guide choice of wire in traversing difficult strictures. Early studies found hydrophilic wires to be more successful in cannulation across strictures compared with traditional monofilament wires. Factors to consider in wire choice include construction material, tip characteristics, and diameter. Wire tips can be straight, tapered, J shaped, or looped; however, there is a paucity of literature to support their design goals.
Stent Choice
Plastic stents are still the stent of choice for most benign conditions, but there are multiple studies being undertaken assessing self-expandable metal biliary stents (SEMS). Although many studies comparing different plastic stents were designed with malignant biliary obstruction, stents characteristics are extrapolated to the benign cohort. Stent characteristics vary in their construction material, length, angulation, and antimigration properties. Polyethylene flanged stents were first introduced more than 20 years ago and have survived the test of time despite attempts to improve on their longevity. Both Teflon and hydrophilic polymer-coated polyurethane (HPCP) materials have been compared with polyethylene. Van Berkel and colleagues first compared Teflon with polyethylene stents and found no difference in duration of patency. HPCP was initially thought to reduce biofilm formation with its lower friction coefficient and hydrophilic property, but van Berkel and colleagues found a shorter patency period in the HPCP group. The Tannenbaum stent (Cook UK, Letchworth, Hertfordshire, UK) was designed to improve longevity by eliminating side holes and changing stent material from polyethylene to Teflon, with 3 prospective studies failing to identify superiority, and raising concerns about higher migration rates. Dietary fibers have been confirmed to fill the lumen of biliary stents to contribute to occlusion; however, addition of an antireflux valve (Fusion Marathon, Cook Inc., Winston, Salem, NC, USA) has yet to prove advantageous. More recently, another novel stent construction limiting the central lumen by using a winged perimeter star-shaped design (Viaduct stent, GI Supply, Camp Hill, PA, USA) has been introduced into the market ( Fig. 1 ). As yet, there are no studies comparing this design with the traditional stents but the authors have a protocol under review for a randomized trial comparing the polyethylene stent with the Viaduct stent, with results anticipated in 2013.
Metal Biliary Stents
Interest continues in SEMS in the treatment of benign disease. It has theoretic advantages in terms of a narrow deployment system, innate expansile force minimizing the need for dilatation, and a larger postdeployment diameter to minimize occlusion and consequently the duration for stent change. Early studies on fully uncovered SEMS placed without the intention of subsequent removal had a high rate of occlusion at approximately 2 years. These stents are not recommended for benign disease because of problems with stent embedment making them hard to remove. SEMS may be fully covered or partially covered with the proximal and distal ends bare. The latter are more difficult to remove because of tissue ingrowth at the uncovered ends ( Fig. 2 ). Most published SEMS studies have stent therapy with a duration of 2 to 6 months, and stricture resolution has ranged from 60% to 100% at the time of stent removal. Migration rates have varied between 10% and 40%, with most fully covered SEMS studies at the higher end of the range. Another potential complication of SEMS in benign disease is secondary stricture formation. In the next 5 years, we anticipate results from prospective studies with longer follow-up than what is presently published to provide clarity regarding SEMS selection and duration of therapy ( ClinicalTrials.gov identifiers NCT01238900, NCT00945516, NCT01221311). Evaluation of new stent designs with anchoring flaps or a variable contour (Niti-S bumpy-type stent, Taewoong Medical, Seoul, Korea) may overcome current concerns of migration. Several recent case reports have also described the use of combined metal and plastic stents in the management of hilar strictures and to avoid stent migration. Table 3 outlines published trials on the use of metal biliary stents in benign disease.
| Study | Year | Number of Patients | Indication | Stent Type | Duration, Range (mo) | Follow-up Duration, Range (mo) | Result | Complication |
|---|---|---|---|---|---|---|---|---|
| Bruno et al , a | 2005 | 4 | CP | FC (Hanaro, MI tech, Seoul, Korea) | 3–6 | Nil | 75% stricture resolution | Proximal migration (1) |
| Tringali et al , a | 2005 | 6 | CP | PC (not stated) | N/A | 35 (33–37) | 20-mo patency (range 16–24 mo) | Not reported |
| Cantu et al | 2005 | 14 | CP | PC (Wallstent, Boston Scientific, Natick, MA) | 21 (18–33) | 22 (12–33) | 50% stent dysfunction, median patency 21 mo (range 18–33 mo) | Cholangitis (5) Ingrowth (5) Distal migration (1) Proximal migration (1) |
| Kuo et al | 2006 | 3 | OLT | FC (Viabil, WL Gore & Associates, Flagstaff, AZ) | 38 d (0–49 d) | 38 (0–49) | 100% unremarkable cholangiogram at time of removal | Septicemia (1) Misplacement (1) |
| Kahaleh et al | 2008 | 79 | CP (32), OLT (16), BS (24), I (4), PS (3) | PC (microvasive endoscopy, Boston Scientific, Natick MA | 4 (1–28) | 12 (3–26) | Resolution: 77% CP, 94% OLT, 100% other, 90% success overall | Distal migration (2) Proximal migration (6) Bile leak (1) Stricture (6) Pain (2) |
| Cahen et al | 2008 | 6 | CP | FC (Hanaro, MI tech Seoul, Korea) | 3–6 | 28–36 | 66% resolution, 1 stricture recurrence at 6 mo | Stent embedment (2) Proximal migration (1) |
| Park et al | 2011 | 43 | CP (11), BS (26), OLT (2), PS (4) | FC (MI Tech Seoul, and Standard Sci-Tech, Seoul, Korea) | 4–6 | 3–5 | 84% resolution, 7 patients with recurrence | Proximal migration (1) Distal migration (6) Post-ERCP pancreatitis (6) Cholangitis (2) |
Stricture Dilation
Strictures can be dilated using either a balloon or bougie system. There are no head-to-head comparisons between the 2 techniques. The degree of dilatation is guided by the size of the bile duct distal to the stricture. Anecdotally, balloon dilation of focal strictures has the advantage of showing a waist fluoroscopically, the persistence of which indicates a need for further dilatation ( Fig. 3 ). Dilatation soon after biliary anastomosis can lead to dehiscence, so a more cautious approach is required in this setting. Most strictures should be stented after dilatation, because recurrence rates of nearly 50% have been described with dilatation alone, although this is not an absolute rule, and does depend on the underlying cause.
Cholangioscopy
Cholangioscopy has a diagnostic usefulness in its ability to visualize and obtain tissue from the stricture. Its use is limited by the need for 2 endoscopists in most mother-daughter setups, endoscopist expertise, the need for extended procedure time, and cost of additional equipment.
Aside from targeted biopsies, the presence of dilated and tortuous vessels, otherwise termed capillary sign or tumor vessel sign, has been described to be highly specific for malignancy, although subsequent studies have found benign stricture during the active inflammatory stage to mimic these vascular abnormalities. Other cholangioscopic appearances associated with malignancy include friability and irregular surface. Two studies found the sensitivity of cholangioscopy for diagnosing malignancy in indeterminate strictures to be more than 89%, but this was also associated with a higher false-positive rate with specificity as low as 86%.
Therapeutic application of cholangioscopy in benign strictures is limited. There have been reports of cholangioscopy-assisted guidewire placement in strictures that were difficult to traverse, but currently other techniques such as EUS-assisted cholangiography and guidewire placement or PTC-guided rendezvous remain more accessible options in most centers.
EUS
EUS compliments ERCP through its sonographic and tissue sampling capabilities. Although EUS with FNA of a visualized mass has a yield of approximately 90%, FNA of biliary strictures in the absence of a mass is less rewarding. Studies of the diagnostic accuracy of EUS in excluding malignant biliary strictures have been limited by small sample size, differing gold standards, and often by a heterogeneous study population. FNA of distal biliary strictures has a higher diagnostic yield, perhaps because of its more intimate relationship to the transducer. Two studies assessing indeterminate strictures found the sensitivity of FNA alone to be less than 50%, but, in 1 of the studies, sonographic features of a pancreatic head mass or irregular bile duct wall had a positive predictive value for malignancy of 100% and a negative predictive value of 84%. Two meta-analyses on EUS with or without FNA for extrahepatic bile duct strictures have been performed. Inclusion criteria in both was broad, with 1 including gallbladder masses, and many studies were included before 1997. Pooled sensitivities were 0.78 and 0.84, and specificity was 0.84 and 1.00.
From a therapeutic perspective, EUS can assist in stent placement if standard ERCP-guided transpapillary placement has failed, either in a rendezvous manner with ERCP, or by placing a stent in the biliary tree to traverse the stomach or duodenum. This technique is challenging, partly because of the oblique view of the linear echoendoscope, and is still limited to experienced centers, but, as newer echoendoscopes become available, including a forward-viewing echoendoscope, EUS may play a more prominent role in therapeutic biliary strictures.
Intraductal ultrasound
Intraductal ultrasound has a sensitivity and specificity of between 80 and 90% in published studies in differentiating benign from malignant strictures. It can identify echolayer disruption of the bile duct wall, as well as small adjacent mass lesions. Its use is limited by operator expertise, the often challenging imaging criteria for diagnosis, and the biliary contamination risk and subsequent need for ERCP and biliary stenting. Where available, its role is most appropriate to patients with a high suspicion of malignancy when ERCP and EUS have both failed to prove malignancy.
Confocal laser endomicroscopy
Probe-based confocal endomicroscopy has gained momentum as an emerging entity in its diagnostic usefulness in indeterminate biliary strictures. It uses a laser scanning unit to emit light and illuminate tissue. The light is absorbed by fluorophores, enhanced via intravenous fluorescein, and the reflected fluorescence is detected by the probe and optically relayed to the processing unit. This technique allows real-time histologic assessment of the target epithelium. The Miami classification for pancreaticobiliary strictures has recently been developed to standardize imaging features consistent with malignancy ( Table 4 ). In a validation study involving 4 endoscopists and 41 patients, 5 of the 6 Miami criteria met acceptable interobserver variability with a κ value of more than 0.4. New-generation probes have now been manufactured for compatibility with both the working channel of duodenoscopes and cholangioscopes. Published studies to date have described sensitivities of between 83% and 98%, specificities of 67% to 75%, and accuracy of 81% to 86%. Further studies are required to validate and refine the diagnostic criteria and accuracy, address issues relating to training requirements, and confirm safety profile before it is ready to be endorsed into mainstream practice.
| Suggestive for Malignancy | Suggestive for Benign Strictures |
|---|---|
| Thick, dark bands (>40 μm) | Thin, dark (branching) bands |
| Thick white bands (>20 μm) | Thin, white bands |
| Dark clumps | — |
| Epithelium visualized (villi, glands) | — |
| Fluorescein leakage | — |
Management of specific disorders
Postoperative Benign Biliary Strictures
Postoperative benign biliary strictures occur most frequently after cholecystectomy, either as a consequence of direct ductal trauma (partial or complete transection by clipping or ligation) or ischemic insult from thermal or dissection injury. It is usually diagnosed 6 to 12 months after surgery, and earlier presentations can be associated with bile leak. In one of the earliest reported series on endoscopic management of bile duct complications after cholecystectomy, only half of the cohort developed abdominal pain and none were septic.
The widespread application of laparoscopic approach to cholecystectomy has been associated with an increasing incidence of bile duct injuries. Estimated incidence has increased from approximately 0.1% to 0.2% to 0.4% to 0.6% compared with earlier studies in which open cholecystectomy was the mainstay of treatment. Management of bile duct injuries has been predominantly surgical in the past. Although initial surgical success was reported to be more than 90%, follow-up studies have found a 9% to 25% recurrence rate, a morbidity rate of 40%, and a mortality of 1.3% to 1.7%.
Endoscopic therapy has been associated with variable success, with reported response rates between 40% and 90%. The diverse response rates are likely related to different intervals of patient follow-up after stent removal, because stricture recurrence can occur many months to years later. Two studies with a longer follow-up interval (median of 81 and mean of 23 months) reported a recurrence rate of 20% to 30% within 2 years. Most published reviews are retrospective and include a heterogeneous cohort (some include transplant anastomotic strictures, some combine strictures and bile leak in analysis), variable and nonstandardized protocol (not all centers undertook rendezvous procedures), and variable follow-up and compliance. In 2 of the largest series, Bergman and colleagues and Costamagna and colleagues published retrospective studies in 2001 with long-term follow-up (mean of 9.1 years and 48.8 months respectively). Costamagna and colleagues took a more aggressive approach to management by dilating and inserting the maximal number of stents possible and achieved a 76% completion rate with all but 1 case sustaining long-term relief, compared with only 47% in the study by Bergman and colleagues.
Because of the limitations of high-quality evidence, the authors consider the following approach to management
- •
Endoscopic approach is a reasonable first line in patients suspected of having a postoperative biliary stricture, with an anticipated response rate of approximately 70%
- •
In patients with complete biliary obstruction in whom guidewire passage is difficult, we proceed to a rendezvous or surgical approach
- •
Biliary stenting should be performed for 6 to 18 months, with stent changes every 3 months
- •
Given the success rates of most studies deploying multiple stents, this approach is reasonable
- •
The need for universal stricture dilatation is unclear but is indicated if the endoscopist anticipates difficulty passing the stent across a stricture.
Transplant Biliary Strictures
Bile leaks and strictures are the most common biliary complications following liver transplantation. The incidence of posttransplant biliary strictures varies widely among different groups. In deceased donor transplants, the incidence is between 5% and 25%, and up to 32% for living donor transplants. Posttransplant biliary strictures are classified as anastomotic or nonanastomotic, and early (within 1 month) or late. Early strictures are generally related to perioperative events (excessive cautery, dissection, or tension of the duct anastomosis) and are mostly anastomotic. Late strictures are mainly caused by vascular insufficiency and fibrosis. Several risk factors have been identified as being associated with posttransplant strictures, including the type of biliary anastomosis (Roux-en-Y choledochojejunostomy vs choledochocholedochostomy), the use of T tube (which is now less commonly used), hepatic artery thrombosis, prolonged warm and cold ischemia time, ABO incompatibility, use of donor after cardiac death, and posttransplant bile leak. Accurate assessment of these subtypes helps guide the most appropriate course of management and predict likelihood of success.
Patients usually present with symptomatic or asymptomatic increase in liver function tests, but, unlike other causes of biliary obstruction, dilatation of the donor bile ducts is an unreliable indictor of biliary obstruction. As such, cholangiography, whether it be noninvasive or invasive, is often required to diagnosis a stricture when the clinical suspicion arises. A Doppler of the hepatic vessels should be included in the initial assessment to exclude hepatic artery thrombosis. The choice of MRCP or a diagnostic ERCP is guided by local expertise and availability, as well as the pretest probability of requiring intervention. MRCP has a sensitivity and specificity of between 87% and 100% and a negative predictive value of more than 90% in diagnosing biliary strictures. Scintigraphy has also been shown to have a high specificity but lower sensitivity for diagnosing bile duct strictures.
Characteristic cholangiographic findings result from differing pathophysiology. Nonanastomotic strictures usually arise from biliary ischemia secondary to hepatic artery stenosis or thrombosis, because this is the sole blood supply to the biliary tree. They typically occur at the hilum and can progress to the intrahepatic ducts, occasionally in multiple locations. They typically occur earlier than anastomotic strictures, with a mean time to stricture development between 3 and 6 months. Disease recurrence, especially PSC and infection, are other causes of nonanastomotic strictures. Anastomotic stricture usually occurs secondary to fibrosis and is represented by a short focal stricture. Early anastomotic strictures can be a result of local edema and inflammation, which often resolves over a period of 2 to 3 months.
Endoscopic therapy is now widely recognized as the first-line management approach for posttransplant biliary strictures, with PTC and surgical bypass reserved for unsuccessful cases. In patients with Roux-en-Y anastomosis, ERCP may not be possible, and PTC with dilatation and catheter placement may be more appropriate. Retransplantation remains a final option if other therapies fail.
Anastomotic Strictures
Most anastomotic strictures arise within the first 12 months of transplantation ( Fig. 4 ). Early anastomotic strictures, usually caused by edema and inflammation, have a good response to therapy and are less likely to recur, with resolution of stricture over an average of 3 months. Delayed-onset anastomotic strictures, a consequence of fibrotic scarring, require a more protracted course of therapy. Most published studies have been retrospective, and the few prospective studies have been limited by small sample size and a heterogeneous cohort. Balloon dilatation to a maximal diameter of the duct up to 10 mm followed by insertion of multiple plastic stents decreases stricture recurrence by 62% to 31% compared with balloon dilatation alone. Multiple published studies have shown that a protocol of balloon dilatation with 3-monthly stent changes with insertion of multiple side-by-side stents increases success to 80% to 90% ( Fig. 5 ). Treatment is usually maintained for 12 to 24 months before it is considered a failure.
Related posts:
Therapeutic and Advanced ERCP Is Rapidly Progressing
Endoscopic Retrograde Cholangiopancreatography for Stone Burden in the Bile and Pancreatic Ducts
Sampling at ERCP for Cyto- and Histopathologicical Examination
Endoscopic Retrograde Cholangiopancreatography for Distal Malignant Biliary Stricture
Complications of Endoscopic Retrograde Cholangiopancreatography
Endoscopic Retrograde Cholangiopancreatography
Stay updated, free articles. Join our Telegram channel
Full access? Get Clinical Tree
