Intraoperative ultrasound as an educational guide for laparoscopic biliary surgery

AIM： To analyze the efficacy of routine intraoperative ultrasound （IOUS） as a guide for understanding biliary tract anatomy, to avoid bile duct injury （BDI） after laparoscopic cholecystectomy （LC）, as well as any burden during the learning period. METHODS： A retrospective analysis was performed using 644 consecutive patients who underwent LC from 1991 to 2006. An educational program with the use of IOUS as an operative guide has been used in 276 cases since 1998. RESULTS： IOUS was highly feasible even in patients with high-grade cholecystitis. No BDI was observed after the introduction of the educational program, despite 72% of operations being performed by inexperienced surgeons. Incidences of other morbidity, mortality, and late complications were comparable before and after the introduction of routine IOUS. However, the operation time was significantly extended after the educational program began （P 〈 0.001）, and the grade of laparoscopic cholecystitis （P = 0.002）, use of IOUS （P = 0.01）, and the experience of the surgeons （P = 0.05） were significant factors for extending the length of operation. CONCLUSION： IOUS during LC was found to be a highly feasible modality, which provided accurate, real- time information about the biliary structures. Theeducational program using IOUS is expected to minimize the incidence of BDI following LC, especially when performed by less-skilled surgeons.     

Bile duct injury repair: when? what? who?

Laparoscopic cholecystectomy is associated with a two-to-four times higher risk of bile duct injury (BDI) than open cholecystectomy. BDI can lead to significant morbidity and even mortality. The first priority in BDI is to control peritoneal and biliary sepsis and to convert an acute BDI to a controlled external biliary fistula (EBF) — this can be achieved by endoscopic and/ or radiological intervention in most cases. This should be followed by assessment of the extent of injury — both biliary and vascular. Immediate management of BDI recognized during cholecystectomy depends on the type of injury, the condition of the patient, and the experience of the surgeon. For BDI recognized after cholecystectomy, early repair is not recommended, as the results are poor. The EBF may evolve into a benign biliary stricture (BBS), which should be electively repaired by a Roux-en-Y hepatico-jejunostomy. The use of an endoscopic stent as definitive management of BDI is not recommended. Long-term follow-up is essential after the repair of a BBS, as recurrence can occur several years after repair. Recurrent BBS is best treated with endoscopic balloon dilatation. Excellent early and long-term results can be obtained in specialized units at tertiary care referral centers.     

A new method of preventing bile duct injury in laparoscopic cholecystectomy

AIM: Of all the complications of laparoscopic cholectecystomy, bile duct injury (BDI) is the most serious complication. The prevention of injury to the common bile duct (CBD) remains a significant concern in laparoscopic cholecystectomy (LC). Different kinds of methods have been advanced to avoid this injury but no single method has gained wide acceptance. Because of various limitations of current methodologies we began a study using cold light illumination of the extrahepatic biliary system (light cholangiography LCP) to better visualize this area and thereby reduce the risk of bile duct injury. METHODS: Thirty-six patients with cholelithiasis were divided into two groups. Group I (16 cases) received LCP and group II (20 cases) received methelenum coeruleum cholangiography (MCCP). In group I cold light was used to illuminate the common bile duct by leading an optical fiber into the common duct with a duodenoscope at the time of LC. The light coming from the fiber in the CBD could clearly illuminate the location of CBD and hepatic duct establishing its location relative to the cystic duct. This method was compared with the dye injection technique using methelenum coeruleum. RESULTS: In group I thirteen cases were successfully illuminated and three failed. The cause of three failed cases was due to the difficulty in inserting the fiber into the ampulla of Vater. No complications occurred in the thirteen successful cases. In each of these successful cases the location of the common and hepatic ducts was clearly seen differentiating the ductal system from surrounding anatomy. In ten cases both the left and right hepatic ducts could be seen and in three only the right hepatic ducts were seen. In four of the thirteen cases, cystic ducts were also seen. In group II, eighteen of the twenty cases were successful. The location of extrahepatic ducts became blue differentiating the ductal system from surrounding anatomy. Two cases failed due to a stone obstructing the cystic duct, and extravisation of the dye turned the entire area blue. LCP showed the common and hepatic ducts more clearly than MCCP. CONCLUSION: LCP is the only technique that can clearly and directly show the location of the extrahepatic biliary system and may be useful in selecting cases of uncertain anatomy in the prevention of bile duct injury.     

The long-term effect of bile duct injuries on health-related quality of life: a meta-analysis

Background

The reported effects of biliary injury on health-related quality of life (HRQOL) have varied widely. Meta-analysis methodology was applied to examine the collective findings of the long-term effect of bile duct injury (BDI) on HRQOL.

Methods

A comprehensive literature search was conducted in March, 2012. Because the HRQOL surveys differed among reports, BDI and uncomplicated laparoscopic cholecystectomy (LC) groups'' HRQOL scores were expressed as effect sizes (ES) in relation to a common, general population, standard. A negative ES indicated a reduced HRQOL, with a substantive reduction defined as an ES ≤ −0.50. Weighted logistic regression tested the effects of BDI (versus LC) and follow-up time on whether physical and mental HRQOL were substantively reduced.

Results

Data were abstracted from six publications, which encompass all reports of HRQOL after BDI in the current, peer-reviewed literature. The analytic database comprised 90 ES computations representing 831 patients and 11 unique study groups (six BDI and five LC). After controlling for follow-up time (P ≤ 0.001), BDI patients were more likely to have reduced long-term mental [odds ratio (OR) = 38.42, 95% confidence interval (CI) = 19.14–77.10; P < 0.001] but not physical (P = 0.993) HRQOL compared with LC patients.

Discussion

This meta-analysis of findings from six peer-review reports indicates that, in comparison to LC, there is a long-term detrimental effect of BDI on mental HRQOL.     

Laparoscopic ultrasonography as an alternative to intraoperative cholangiography during laparoscopic cholecystectomy

AIM To assess the role of laparoscopic ultrasound(LUS) as a substitute for intraoperative cholangiography(IOC) during cholecystectomy.METHODS We present a MEDLINE and Pub Med literature search, having used the key-words "laparoscopic intraoperative ultrasound" and "laparoscopic cholecystectomy". All relevant English language publications from 2000 to 2016 were identified, with data extracted for the role of LUS in the anatomical delineation of the biliary tract, detection of common bile duct stones(CBDS), prevention or early detection of biliary duct injury(BDI), and incidental findings during laparoscopic cholecystectomy. Data for the role of LUS vs IOC in complex situations(i.e., inflammatory disease/fibrosis) were specifically analyzed. RESULTS We report data from eighteen reports, 13 prospective non-randomized trials, 5 retrospective trials, and two meta-analyses assessing diagnostic accuracy, with one analysis also assessing costs, duration of the examination, and anatomical mapping. Overall, LUS was shown to provide highly sensitive mapping of the extra-pancreatic biliary anatomy in 92%-100% of patients, with more difficulty encountered in delineation of the intra-pancreatic segment of the biliary tract(73.8%-98%). Identification of vascular and biliary variations has been documented in two studies. Although inflammatory disease hampered accuracy, LUS was still advantageous vs IOC in patients with obscured anatomy. LUS can be performed before any dissection and repeated at will to guide the surgeon especially when hilar mapping is difficult due to fibrosis and inflammation. In two studies LUS prevented conversion in 91% of patients with difficult scenarios. Considering CBDS detection, LUS sensitivity and specificity were 76%-100% and 96.2%-100%, respectively. LUS allowed the diagnosis/treatment of incidental findings of adjacent organs. No valuable data for BDI prevention or detection could be retrieved, even if no BDI was documented in the reports analyzed. Literature analysis proved LUS as a safe, quick, non-irradiating, costeffective technique, which is comparatively well known although largely under-utilized, probably due to the perception of a difficult learning curve. CONCLUSION We highlight the advantages and limitations of laparoscopic ultrasound during cholecystectomy, and underline its value in difficult scenarios when the anatomy is obscured.     

Isolated right posterior bile duct injury following cholecystectomy:Report of two cases

Anatomic variations of the right biliary system are one of the most common risk factors for sectoral bile duct injury(BDI)during cholecystectomy.Isolated right posterior BDI may in particular be a challenge for both diagnosis and management.Herein we describe two cases of isolated right posterior sectoral BDI that took place during laparoscopic cholecystectomy.Despite effective external biliary drainage from the liver hilum in both cases,there was a persistent biliary leak observed which was not visible on endoscopic retrogradecholangiogram.Careful evaluation of images from both endoscopic and magnetic resonance cholangiograms revealed the diagnosis of an isolated right posterior sectoral BDI.These were treated with a delayed bisegmental(segments 6 and 7)liver resection and a Roux-en-Y hepaticojejunostomy respectively with good outcomes at 24 and 4 mo of follow-up.This paper discusses strategies for prevention of such injuries along with the diagnostic and therapeutic challenges it offers.     

Prevention of iatrogenic bile duct injuries in difficult laparoscopic cholecystectomies: is the naso-biliary drain the answer?

Background

Prevention of iatrogenic injuries is of paramount importance in difficult laparoscopic cholecystectomies (LC). The objective of this study was to analyze the effectiveness of cholangiography using a pre-inserted endoscopic naso-biliary drain (ENBD) for navigation during difficult cholecystectomies.

Methods

The study design was a retrospective case analysis. In 508 patients who underwent LC in a tertiary referral university hospital from 1996 through 2007, difficult cholecystectomy was anticipated in 26 patients due to possibly aberrant biliary anatomy (four patients), unclear cystic duct anatomy during magnetic resonance cholangiopancreatography (MRCP) and/or endoscopic retrograde cholangiopancreatography (ERCP) (three patients), and acute cholecystitis (19 patients). An ENBD was inserted during ERCP prior to LC for cholangiography (ENBDC) to facilitate safe dissection during LC. Prevalence of biliary complications was assessed as the main outcome measurement.

Results

The majority (68%) of the patients who underwent ENBDC had complicated cholecystitis. Advanced technical expertise was not required for insertion of an ENBD. In retrospect, ENBDC was useful in prevention of a possible catastrophe in 69% of cases. Open conversion was necessary in five patients and biliary complications occurred in five patients only in the non-ENBD group. There were no procedure-related complications. One limitation of the study was that it was not randomized and there was no comparison with patients without ENBDC.

Conclusions

ENBDC is a useful and safe tool in the prevention of iatrogenic bile duct injuries in LC.     

Donor ductal anomaly is not a contraindication to right liver lobe donation

BackgroundData of living-donor liver transplantation (LDLT) suggested that donor ductal anomaly may contribute to postoperative biliary complications in recipients and in donors. This retrospective study aimed to determine if the occurrence of postoperative biliary stricture in donors or recipients in right-lobe LDLT (RLDLT) is related to donor biliary anatomy type.MethodsWe analyzed our RLDLT recipients’ clinical data and those of their graft donors. The recipients were divided into 2 groups: with and without postoperative biliary stricture. The 2 groups were compared. The primary endpoints were donor biliary anatomy type and postoperative biliary complication incidence; the secondary endpoints were 1-, 3- and 5-year graft and patient survival rates.ResultsTotally 127 patients were included in the study; 25 (19.7%) of them developed biliary anastomotic stricture. In these 25 patients, 16 had type A biliary anatomy, 3 had type B, 2 had type C, 3 had type D, and 1 had type E. In the 127 donors, 96 (75.6%) had type A biliary anatomy, 13 (10.2%) had type B, 6 (4.7%) had type C, 10 (7.9%) had type D, and 2 (1.6%) had type E. Biliary stricture was seen in 2 donors, who had type A biliary anatomy. None of the recipients or donors developed bile leakage. No association between the occurrence of postoperative biliary stricture and donor biliary anatomy type was found (P = 0.527).ConclusionsThe incidence of biliary stricture in donors or recipients after RLDLT was not related to donor biliary anatomy type. As postoperative complications were similar in whatever type of donor bile duct anatomy, donor ductal anomaly should not be considered a contraindication to donation of right liver lobe.     

Tokyo Guidelines 2018: surgical management of acute cholecystitis: safe steps in laparoscopic cholecystectomy for acute cholecystitis (with videos)

In some cases, laparoscopic cholecystectomy (LC) may be difficult to perform in patients with acute cholecystitis (AC) with severe inflammation and fibrosis. The Tokyo Guidelines 2018 (TG18) expand the indications for LC under difficult conditions for each level of severity of AC. As a result of expanding the indications for LC to treat AC, it is absolutely necessary to avoid any increase in bile duct injury (BDI), particularly vasculo‐biliary injury (VBI), which is known to occur at a certain rate in LC. Since the Tokyo Guidelines 2013 (TG13), an attempt has been made to assess intraoperative findings as objective indicators of surgical difficulty; based on expert consensus on these difficulty indicators, bail‐out procedures (including conversion to open cholecystectomy) have been indicated for cases in which LC for AC is difficult to perform. A bail‐out procedure should be chosen if, when the Calot's triangle is appropriately retracted and used as a landmark, a critical view of safety (CVS) cannot be achieved because of the presence of nondissectable scarring or severe fibrosis. We propose standardized safe steps for LC to treat AC. To achieve a CVS, it is vital to dissect at a location above (on the ventral side of) the imaginary line connecting the base of the left medial section (Segment 4) and the roof of Rouvière's sulcus and to fulfill the three criteria of CVS before dividing any structures. Achieving a CVS prevents the misidentification of the cystic duct and the common bile duct, which are most commonly confused. Free full articles and mobile app of TG18 are available at: http://www.jshbps.jp/modules/en/index.php?content_id=47 . Related clinical questions and references are also included.     

Long-term outcomes of delayed biliary strictures following cholecystectomy

BackgroundDelayed biliary strictures (DBS) after cholecystectomy are uncommon and little is known of their aetiology or long-term consequences. The aims of this study were to investigate the clinical and economic impact of DBS after cholecystectomy.MethodsPatients who developed DBS after cholecystectomy were identified from a prospectively collected and maintained database. Risk factors for stricture development, quality of life (QoL) and long-term biliary complication rates were explored. Costs of treatment and follow up were determined. The same outcomes among patients with minor or major bile duct injury (BDI) were used as a comparison.ResultsAmong 44 patients, a laparoscopic converted to open procedure or post cholecystectomy bile leak affected some 18 and 12 patients respectively. Most DBS required surgical treatment (40). Over a median follow-up of 8.9 years after DBS treatment, 16 (36%) patients developed biliary complications (similar to minor, 26%, and major BDI, 40%) and 1 patient died of causes related to the biliary stricture. Costs of treating DBS and its follow up (£14,309.26 per patient), were similar to previously reported costs for major BDI (£15,784).ConclusionDBS typically occur after a technically and/or complicated cholecystectomy. Clinical, economic and QoL outcomes are similar to patients with major BDI.     

Delphi consensus on bile duct injuries during laparoscopic cholecystectomy: an evolutionary cul‐de‐sac or the birth pangs of a new technical framework?

Bile duct injury (BDI ) during laparoscopic cholecystectomy remains a serious iatrogenic surgical complication. BDI most often occurs as a result of misidentification of the anatomy; however, clinical evidence on its precise mechanism and surgeons’ perceptions is scarce. Surgeons from Japan, Korea, Taiwan, and the USA, etc. (n  = 614) participated in a questionnaire regarding their BDI experience and near‐misses; and perceptions on landmarks, intraoperative findings, and surgical techniques. Respondents voted for a Delphi process and graded each item on a five‐point scale. The consensus was built when ≥80% of overall responses were 4 or 5. Response rates for the first‐ and second‐round Delphi were 60.6% and 74.9%, respectively. Misidentification of local anatomy accounted for 76.2% of BDI . Final consensus was reached on: (1) Effective retraction of the gallbladder, (2) Always obtaining critical view of safety, and (3) Avoiding excessive use of electrocautery/clipping as vital procedures; and (4) Calot's triangle area and (5) Critical view of safety as important landmarks. For (6) Impacted gallstone and (7) Severe fibrosis/scarring in Calot's triangle, bail‐out procedures may be indicated. A consensus was reached among expert surgeons on relevant landmarks and intraoperative findings and appropriate surgical techniques to avoid BDI .     

腹腔镜胆囊切除术后胆道损伤实施介入治疗的临床价值观察

目的探讨介入治疗在腹腔镜胆囊切除术（LC）后胆道损伤（BDI）中的临床价值。方法回顾性分析并总结1997年6月至2007年5月收治的24例接受介入治疗的LC术后BDI患者的临床资料。结果按刘允怡胆管损伤分类法,24患者中Ⅰ型5例、Ⅱ型11例、Ⅲ型2例、Ⅳ型6例。2例术中发现BDI并中转开腹,但分别于术后10个月和2年出现胆道感染;22例术后发现,其中13例为LC术后3—12d发现,7例为20～60d发现,2例在术后2年发现。24例患者中5例在接受介入治疗后获得治愈,19例在胆管炎和黄疸得到控制后手术治愈。其中LC术后3—12d发现的13例患者中,6例接受急诊手术,均告失败,而直接接受介入治疗的7例中3例治愈,4例在控制胆管炎和黄疸后择期手术治愈。结论LC术后BDI实施介入治疗,建立必要的胆管内支撑和通畅的胆汁引流,不仅可有效控制胆管炎,消退黄疸,获得全面的胆道树影像,有利于增加手术的安全性,甚至可以起到治愈的效果。     

Risk factors for bile duct injury after laparoscopic cholecystectomy: A protocol for systematic review and meta-analysis

Background:Bile duct injury (BDI) is one of the serious complications in laparoscopic cholecystectomy (LC), but there is currently a lack of systematic review of risk factors related to BDI after LC. This study conducts meta-analysis on the risk factors related to bile duct injury after LC, the purpose is to provide reference basis for preventing and reducing BDI after LC.Methods:Using the Computer to retrieve of Chinese and English databases such as CNKI, WANFANG Data, the VIP Network, PubMed, Embase, the Cochrane Library, etc. The time is from the establishment of each database until August 2021. A case–control study is selected that is related to the risk factors of BDI after LC. This meta-analysis using RevMan 5.4 and State 12.0 software is performed after two researchers independently sift through the literature, extract the data, and evaluate the bias risk included in the study.Results:The risk factors related to BDI after LC will be analyzed by systematic review.Conclusion:The conclusion of this study will play an important role in reducing BDI after LC.OSF Registration:DOI 10.17605/OSF.IO/2B3K9, the registration URL is https://osf.io/2b3k9.     

Hepatectomy after bile duct injury: a systematic review

BackgroundBile duct injury (BDI) after cholecystectomy can lead to recurrent cholangitis, even after biliary reconstruction. This necessitates hepatectomy in a minority of patients. A systematic review was conducted, summarizing the pattern of biliary injury sustained in this group and their outcomes after hepatectomy.MethodsA literature search included the MEDLINE, EMBASE, PubMed and Cochrane libraries. Retrospective cohort studies describing outcomes for hepatectomy after BDI, and the nature of the antecedent BDI, published between 1999 and 2019, were selected.ResultsEight articles described a cohort of 2110 patients with BDI. Of these, 84 underwent hepatectomy. Complex vasculo-biliary injuries had been sustained in most cases. The mean time to hepatectomy was between 26 and 224 months after BDI. A right hepatectomy was performed in 67–89% of cases. Post hepatectomy, intra-abdominal infection (range 0–50%) and bile leaks (range 0–45%) occurred variably. Mortality occurred in three series. Nineteen percent of patients (16 of 84) developed recurrent symptoms at follow up.ConclusionHepatectomy after bile duct injury is an uncommon procedure and represents a salvage strategy when vasculo-biliary injury happens. Liver resection leads to resolution of symptoms in the majority of the cases however postoperative bile leaks and intra-abdominal infection are common.     

Intrahepatic biliary strictures after liver transplantation

Biliary complication has been one of the most common complications after liver transplantation. Nonanastomotic strictures and dilatations involving the intrahepatic biliary tree have been recognized as biliary complications. These lesions were reported to be associated with hepatic artery thrombosis; prolonged preservation time; ABO-incompatible organs; and immunological injury, including injuries to vascular endothelial cells (chronic rejection) and the bile duct (primary sclerosing cholangitis). However, the etiology of these lesions appeared to be mostly related to ischemic injury. Anatomical research on the arterial supply of the bile duct has provided further insights into bile duct blood supply and its surgical implications. The biliary tract is supplied with arterial blood by a vasculature called the peribiliary vascular plexus. Any injury to the peribiliary vascular plexus may contribute to ischemic death of the biliary system mucosa. At many points, the process of liver transplantation exposes the endothelial cells and peribiliary vascular plexus to ischemic injury. The majority of intrahepatic biliary strictures (IHBS) are diffuse or bilateral. A percutaneous or an endoscopic approach has been used as the initial treatment. However, a low threshold for surgical intervention (retransplantation) should be adopted, because these patients demonstrate high mortality. The aim of this article is to review the anatomy, etiology, clinical picture, diagnosis, management, and prognosis of IHBS after liver transplantation.     

Timing of referral impacts surgical outcomes in patients undergoing repair of bile duct injuries

Bile duct injury (BDI) after laparoscopic cholecystectomy (LC) remains a significant surgical challenge. Despite claims to the contrary, the incidence of bile duct injury has remained elevated since the introduction of LC. Several issues regarding the surgical management of BDI are controversial, including: (i) identification of the surgeon and centre most capable of managing the injury, (ii) timing of surgical repair, (iii) incidence and significance of associated vascular injury and (iv) identification of patient factors which significantly impact outcome after repair. Variability in timing of referral of BDI to tertiary centres has been noted in the literature. The impact of timing of referral upon post-operative outcomes after definitive surgery has yet to be clearly investigated. We report our experience with 44 patients who required reconstructive surgery after BDI. In contrast to the many studies available in the literature, patients in the current study were classified according to a modern injury classification system. Additionally, we examined the impact of delayed referral to our centre on short- and long-term outcomes after surgical repair of BDI.     

Using a standardized method for laparoscopic cholecystectomy to create a concept operation-specific checklist

Objectives

Prevalences of bile duct injury (BDI) following laparoscopic cholecystectomy (LC) remain unacceptably high. There is no standardized method for performing an LC. This study aims to describe a standardized technique for LC that will allow for the development of a concept LC checklist, the use of which, it is hoped, will decrease the prevalence of BDI.

Methods

A standardized method for LC was developed based on previously published expert analysis supplemented by video error analysis of operations in which BDI occurred. Established checklist methodology was then used to construct an LC-specific concept checklist.

Results

A five-step technique for the safe establishment of the critical view was created to guide the development of the checklist. The five steps are: (i) confirm the gallbladder lies in the hepatic principal plane and is retracted to the 10 o''clock position; (ii) confirm Hartmann''s pouch is lifted up and toward the segment IV pedicle; (iii) identify Rouvière''s sulcus; (iv) confirm the release of the posterior leaf of the peritoneum covering the hepatobiliary triangle, and (v) confirm the critical view with or without intraoperative cholangiography.

Conclusions

A standardized approach to LC would allow for the creation of an LC-specific checklist that has the potential to lower the prevalence of BDI.     

Current status of endoscopic ultrasound-guided antegrade intervention for biliary diseases in patients with surgically altered anatomy

Endoscopic management of biliary diseases in patients with surgically altered anatomy can be challenging because the altered anatomy makes it difficult to insert an endoscope into the biliary orifice. Even if insertion is feasible, the worse maneuverability of the endoscope and the restriction in available devices and techniques could complicate the procedure. Recently, endoscopic ultrasound-guided antegrade intervention (EUS-AG) has been reported as a useful management method for biliary diseases, especially in patients with surgically altered anatomy. In EUS-AG, the biliary disease is managed in an antegrade fashion through a temporal fistula created under EUS guidance between the intrahepatic biliary duct and upper intestine. In this article, we reviewed the current status of EUS-AG for each biliary diseases, malignant biliary obstruction, bile duct stones, and benign biliary stricture in patients with surgically altered anatomy.     

Biliary navigation surgery using endoscopic nasobiliary drainage tube for the prevention of bile duct injury in laparoscopic cholecystectomy

Bile duct injury is the most troublesome complication in laparoscopic cholecystectomy (LC). The identification of the anatomical relationship between the cystic duct and common bile duct is one of the most important points for the safe LC. Therefore, we introduced a biliary navigation surgery using endoscopic nasobiliary drainage (ENBD) tube to avoid bile duct injury during LC. The benefit of intraoperative cholangiography using an ENBD tube is that the identification of the anatomical relationship between the cystic duct and common bile duct can be confirmed by using intraoperative cholangiography through the ENBD tube. We consider that ENBD tube is useful for identifying the biliary tract by repeated intraoperative cholangiography and, thus, for preventing injury to the bile duct in LC.     

Magnetic resonance imaging and diseases of the liver and biliary tract. Part 2. Magnetic resonance cholangiography and angiography and conclusions

Magnetic resonance cholangiography (MRC) relies on the strong T2 signal from stationary liquids, in this case bile, to generate images. No contrast agents are required, and the failure rate and risk of serious complications is lower than with endoscopic retrograde cholangiopancreatography (ERCP). Data from MRC can be summated to produce an image much like the cholangiogram obtained by using ERCP. In addition, MRC and conventional MRI can provide information about the biliary and other anatomy above and below a biliary obstruction. This provides information for therapeutic intervention that is probably most useful for hilar and intrahepatic biliary obstruction. Magnetic resonance cholangiography appears to be similar to ERCP with respect to sensitivity and specificity in detecting lesions causing biliary obstruction, and in the diagnosis of choledocholithiasis. It is also suited to the assessment of biliary anatomy (including the assessment of surgical bile-duct injuries) and intrahepatic biliary pathology. However, ERCP can be therapeutic as well as diagnostic, and MRC should be limited to situations where intervention is unlikely, where intrahepatic or hilar pathology is suspected, to delineate the biliary anatomy prior to other interventions, or after failed or inadequate ERCP. Magnetic resonance angiography (MRA) relies on the properties of flowing liquids to generate images. It is particularly suited to assessment of the hepatic vasculature and appears as good as conventional angiography. It has been shown to be useful in delineating vascular anatomy prior to liver transplantation or insertion of a transjugular intrahepatic portasystemic shunt. Magnetic resonance angiography may also be useful in predicting subsequent variceal haemorrhage in patients with oesophageal varices.