Value of MR Cholangiography in Patients with Iatrogenic Bile Duct Injury After Cholecystectomy

Magnetic Resonance Cholangiography Diagnosing Post-cholecystectomy Biliary Injuries

OBJECTIVE

This study aimed to determine the diagnostic performance of contrasted magnetic resonance cholangiography for detecting bile duct lesions following cholecystectomy.

MATERIALS AND METHODS

A retrospective case series study was conducted that included patients over 18 years of age with suspected bile duct injury after cholecystectomy, who underwent contrasted magnetic resonance cholangiography, and who also had endoscopic retrograde cholangiopancreatography, surgery, or subsequent clinical follow-up. The images were interpreted by two radiologists who assigned the type of lesion according to the Strasberg classification. Qualitative variables were represented by frequencies and proportions, while quantitative variables were described using measures of central tendency and dispersion. Sensitivity, specificity, and predictive values were assessed, along with interobserver variability, using the kappa index.

RESULTS

We included 20 patients with a median age of 51.5 years (interquartile range: 35), and 14 (70%) were women. In all 20 patients, lesions were identified on magnetic resonance cholangiography, of which 19 were confirmed with the gold standard for a positive predictive value of 100% (hepatobiliary-specific contrast agents) and 92% (extracellular contrast). The most frequent lesions were Strasberg E2 and E4 in five patients each. The kappa index was 1 in determining the presence or absence of bile duct injury and 0.9 in the Strasberg classification.

CONCLUSION

Contrasted magnetic resonance cholangiography is a method with high positive predictive value and almost perfect interobserver agreement for diagnosing bile duct lesions after cholecystectomy.

Liver-Specific Contrast-Enhanced Magnetic Resonance Cholangio-Pancreatography (Ce-MRCP) in Non-Invasive Diagnosis of Iatrogenic Biliary Leakage

Current non-invasive diagnostic modalities of iatrogenic bile leak (BL) are not particularly sensitive and often fail to localise the BL origin. Percutaneous transhepatic cholangiography (PTC) and endoscopic retrograde cholangiopancreatography (ERCP) are considered the gold standard, yet are invasive studies with potential complications. Ce-MRCP has been not comprehensively studied in this setting but may prove particularly helpful given its non-invasive nature and the anatomical dynamic detail. This paper reports a monocentric retrospective study of BL patients referred between January 2018 and November 2022 submitted to Ce-MRCP followed by PTC. The primary outcome was the accuracy of Ce-MRCP in detecting and localising BL compared to PTC and ERCP. Blood tests, coexisting cholangitis features and time for leak resolution were also investigated. Thirty-nine patients were included. Liver-specific contrast-enhanced MRCP detected BL in 69% of cases. The BL localisation was 100% accurate. Total bilirubin above 4 mg/dL was significantly associated with false negative results of Ce-MRCP. Ce-MRCP is highly accurate in detecting and localising BL, but sensitivity is significantly reduced by a high bilirubin level. Ce-MRCP may be very useful in early BL diagnosis and in accurate pre-treatment planning, but can only be reliably used in selected patients with TB < 4 mg/dL. Non-surgical techniques, both radiological and endoscopic, are proven to be effective in terms of leak resolution.

MRI evaluation of bile duct injuries and other post-cholecystectomy complications

Laparoscopic cholecystectomy is one of the most common procedures performed each year and can be associated with various post-operative complications. Imaging is integral to diagnosis and management of patients with suspected cholecystectomy complications, and a thorough understanding of normal and abnormal biliary anatomy, risk factors for biliary injury, and the spectrum of adverse events is crucial for interpretation of imaging studies. Magnetic resonance cholangiography (MRC) enhanced with hepatobiliary contrast agent is useful in delineating biliary anatomy and pathology following cholecystectomy. In this article, we provide a protocol for contrast-enhanced MR imaging of the biliary tree. We also review the classification and imaging manifestations of post-cholecystectomy bile duct injuries in addition to other complications such as bilomas, retained/dropped gallstones, and vascular injuries.

Remnant Cystic Duct Disease After Cholecystectomy: A Case Series

BACKGROUND

Remnant cystic duct (RCD) may be responsible for postcholecystectomy syndrome. We present our experience with the management of remnant cystic duct disease (RCDD) after cholecystectomy.

METHODS

Over a period of 5 years, 10 patients underwent reoperation for RCDD in our hospital. Cystic duct was identified by intraoperative exploration.

RESULTS

There were 4 men and 6 women ranging in age from 37 to 76 years (median, 60.40 y). All 10 had biliary pain, 5 had jaundice, and 2 had pancreatitis. The time from initial cholecystectomy to reoperation ranged from 4 to 28 years (median, 12.22 y). Eight patients had an abnormal liver function. Six of these 8 patients (75%) were diagnosed by magnetic resonance cholangiopancreatography. In 7 patients treated by completed cholecystectomy (6 by laparoscopy and 1 by laparotomy), pathology proved the presence of an RCD and chronic cholecystitis. The other 3 patients were treated by removing stones. All patients had 6- to 14-day hospital stays after reoperation, except for 1 patient with a 3-day stay.

CONCLUSIONS

RCDD may be a more reasonable explanation for a source of postcholecystectomy syndrome. Magnetic resonance cholangiopancreatography has a role in the diagnosis of RCDD. We believe that excision of diseased RCD is necessary and that laparoscopic surgery is feasible.

Intrahepatic bile duct variation: MR cholangiography and implication in hepatobiliary surgery

Background

The aim of this study was to assess the prevalence of biliary anatomical variants using 3-T MR cholangiography (MRC) with its impact in reduction of the complication of hepatobiliary surgical techniques.

Results

MRC was applied to 120 subjects (24 potential liver donors and 96 volunteers) and the right posterior hepatic duct insertion was documented, and accordingly, the biliary variants were classified based on Huang classification (Huang et al, Transplant Proc 28: 1669–1670, 1996).

Biliary anatomic variants were divided based on Huang classification: Huang A1, 65.83% (n = 79); Huang A2, 11.67% (n = 14); Huang A3, 13.3% (n = 16); Huang A4, 7.5% (n = 9); and Huang A5, 1.67% (n = 2). The total frequency for A2, A3, A4, and A5 was 34.17% (n = 41). The distance between RPHD insertion and the junction of right and left hepatic ducts (L) was measured, and Huang A1 cases were then subtyped into S1 subtype (L > 1 cm) and S2 subtype (L ≤ 1 cm). We had 52 subjects with subtype S1 (43.33%) and 27 subjects with subtype S2 (22.5%).

Twenty-three subjects had bile duct exploration or intraoperative cholangiograms and showed Huang type A1 in 14 (60.87%), type A2 in 3 (13.05%), and type A3 in 6 (26.08%). Twenty-two (95.65%) had the same classification in MRC and intraoperative while only one case (4.35%) was considered as A2 at MRC but the intraoperative classification was Huang A3, which was attributed to the insertion of the RPHD insertion at the distal end of the left hepatic duct.

Conclusion

MRC is an accurate tool for biliary tract mapping before hepatobiliary surgery to provide excellent identification of biliary variants which can reduce the incidence of biliary complications.

An Update on Iatrogenic Biliary Injuries: Identification, Classification, and Management

Common bile duct injury is a feared complication of cholecystectomy, with an incidence of 0.1% to 0.6%. A majority of injuries go unnoticed at index operation, and postoperative diagnosis can be difficult. Patient presentation can vary from vague abdominal pain to uncontrolled sepsis and peritonitis. Diagnostic evaluation typically begins with ultrasound or CT scan in the acute setting, and source control is paramount at time of presentation. In a stable patient, hepatobiliary iminodiacetic acid scan can be useful in identifying an ongoing bile leak, which requires intervention. A variety of diagnostic techniques define biliary anatomy. Treatment often requires a multidisciplinary approach.

Early cross-sectional imaging following open and laparoscopic cholecystectomy: a primer for radiologists

Abstract

Performed on either an elective or urgent basis, cholecystectomy currently represents the most common abdominal operation due to the widespread use of laparoscopy and the progressively expanded indications. Compared to traditional open surgery, laparoscopic cholecystectomy minimised the duration of hospitalisation and perioperative mortality. Albeit generally considered safe, cholecystectomy may result in adverse outcomes with non-negligible morbidity. Furthermore, the incidence of worrisome haemorrhages and biliary complications has not been influenced by the technique shift. Due to the growing medico-legal concerns and the vast number of cholecystectomies, radiologists are increasingly requested to investigate recently operated patients. Aiming to increase familiarity with post-cholecystectomy cross-sectional imaging, this paper provides a brief overview of indications and surgical techniques and illustrates the expected early postoperative imaging findings. Afterwards, most iatrogenic complications following open, converted, laparoscopic and laparo-endoscopic rendezvous cholecystectomy are reviewed with examples, including infections, haematoma and active bleeding, residual choledocholithiasis, pancreatitis, biliary obstruction and leakage. Multidetector computed tomography (CT) represents the “workhorse” modality to rapidly investigate the postoperative abdomen in order to provide a reliable basis for an appropriate choice between conservative, interventional or surgical treatment. Emphasis is placed on the role of early magnetic resonance cholangiopancreatography (MRCP) and additional gadoxetic acid-enhanced MRCP to provide a non-invasive anatomic and functional assessment of the operated biliary tract.

Teaching Points

• Having minimised perioperative mortality and hospital stay, laparoscopy has now become the first-line approach to performing cholecystectomy, even in patients with acute cholecystitis.

• Laparoscopic, laparo-endoscopic rendezvous, converted and open cholecystectomy remain associated with non-negligible morbidity, including surgical site infections, haemorrhage, residual lithiasis, pancreatitis, biliary obstruction and leakage.

• Contrast-enhanced multidetector computed tomography (CT) is increasingly requested early after cholecystectomy and represents the “workhorse” modality that rapidly provides a comprehensive assessment of the operated biliary tract and abdomen.

• Magnetic resonance cholangiopancreatography (MRCP) is the best modality to provide anatomic visualisation of the operated biliary tract and is indicated when biliary complications are suspected.

• Additional gadoxetic acid (Gd-EOB-DTPA)-enhanced MRCP non-invasively provides functional biliary assessment, in order to confirm and visualise bile leakage.

Noninvasive Imaging of the Biliary Tree for the Interventional Radiologist

Patients with suspected biliary tract disease often pose a diagnostic challenge to the clinician and radiologist. Although advances across all imaging modalities, including ultrasound, computed tomography, and magnetic resonance, have improved our diagnostic accuracy for biliary disease, many of the imaging findings remain nonspecific. Recognition of key imaging findings combined with knowledge and understanding of the clinical context is essential to piecing together a diagnosis and guiding management for patients with biliary disease. Although there is a wide range of biliary pathology, interventional radiologists most commonly play a role in the management of biliary obstruction and leak.

Hepato-pancreato-biliary emergencies for the acute care surgeon: etiology, diagnosis and treatment

Hepatopancreatobiliary (HPB) emergencies include an ample range of conditions with overlapping clinical presentations and diverse therapeutic options. The most common etiologies are related to cholelithiasis (acute cholecystitis, pancreatitis, and cholangitis) and non-traumatic injuries (common bile duct or duodenal). Although the true incidence of HPB emergencies is difficult to determine due to selection and reporting biases, a population-based report showed a decline in the global incidence of all severe complications of cholelithiasis, primarily based on a reduction in acute cholecystitis. Even though patients may present with overlapping symptoms, treatment options can be varied. The treatment of these conditions continues to evolve and patients may require endoscopic, surgical, and/or percutaneous techniques. Thus, it is essential that a multidisciplinary team of HPB surgeons, interventional gastroenterologists and radiologists are available on an as needed basis to the Acute Care Surgeon. This focused manuscript is a contemporary review of the literature surrounding HPB emergencies in the context of the acute care surgeon. The main aim of this review is to offer an update of the diagnosis and management of HPB issues in the acute care setting to improve the care of patients with potential HPB emergencies.

Iatrogenic biliary injuries: identification, classification, and management

Because it offers several advantages over open cholecystectomy, laparoscopic cholecystectomy has largely replaced open cholecystectomy for the management of symptomatic gallstone disease. The only potential disadvantage is a higher incidence of major bile duct injury. Although prevention of these biliary injuries is ideal, when they do occur, early identification and appropriate treatment are critical to improving the outcomes of patients suffering a major bile duct injury. This report delineates the key factors in classification (and its relationship to mechanism and management), identification (intraoperative and postoperative), and management principles of these bile duct injuries.

MR imaging of the biliary system

Although ultrasound, computed tomography, and cholescintigraphy play essential roles in the evaluation of suspected biliary abnormalities, magnetic resonance (MR) imaging and MR cholangiopancreatography can be used to evaluate inconclusive findings and provide a comprehensive noninvasive assessment of the biliary tract and gallbladder. This article reviews standard MR and MR cholangiopancreatography techniques, clinical applications, and pitfalls. Normal biliary anatomy and variants are discussed, particularly as they pertain to preoperative planning. A spectrum of benign and malignant biliary processes is reviewed, emphasizing MR findings that aid in characterization.

The Value of Cholangiography through Jackson-Pratt Drains in the Management of Postoperative Biliary Injuries

Iatrogenic biliary injury is the most significant complication after laparoscopic cholecystectomy. We present our experience with an alternative diagnostic approach using transcatheter cholangiography (TCC) through a Jackson-Pratt (JP) drain and discuss potential benefits and limitations of the technique. From March 2002 to February 2012, 40 patients with major postoperative biliary injury underwent biliary reconstruction at our institution. Mean age was 51.7 ± 18.1 years (range, 19 to 86 years) with 30 (75%) females. Seventeen (42.5%) injuries were detected intraoperatively and in 13 (32.5%) cases, JP drains were placed for biliary drainage. Lesions were classified according to Bismuth grade: I (10 patients [25%]), II (10 patients [25%]), III (six patients [15%]), IV (10 patients [25%]), and V (four patients [10%]). TCC was performed in seven patients with JP drains (53.8%). It fully defined the injury site in three cases of limited magnetic resonance cholangiopancreatography (MRCP) such as common hepatic duct and common bile duct leaks and in four cases (57.1%) that endoscopic retrograde cholangiopancreatography (ERCP) was limited as a result of clipping of the distal common bile duct. TCC showed promising results in cases of limited MRCP and ERCP such as fistulous orifices or leakage. It may represent an alternative adjunct in the diagnostic armamentarium of complex biliary injuries.

Biliary-colonic fistula caused by cholecystectomy bile duct injury

Biliary-colonic fistula is a rare complication after laparoscopic cholecystectomy. We present a case of post-cholecystectomy iatrogenic biliary injury that resulted in a fistula between the common hepatic duct and large bowel. Magnetic resonance cholangiopancreatography provided good visualization of injury even with concurrent normal level of alkaline phosphatase. Radiologic findings and surgical management of this condition are discussed in detail.

Radiologic assessment of hepatobiliary surgical complications

The complexity of hepatobiliary procedures continues to evolve at a rapid rate, with an increasing number of living donor liver transplants and extensive cancer resections being performed. The associated complications are a significant cause of morbidity and mortality, and are often complex injuries, involving both vascular and biliary structures. In this paper we describe the complications associated with laparoscopic cholecystectomy, liver transplant surgery, and hepatic resection. Focus is on the classical imaging appearances, imaging modality options, and varying management strategies for these injuries, to show how the radiologist's role is vital in ensuring the correct diagnosis is made and the appropriate treatment is instigated.

Non-invasive detection of biliary leaks using Gd-EOB-DTPA-enhanced MR cholangiography: comparison with T2-weighted MR cholangiography

Objective

To evaluate the added role of T1-weighted (T1w) gadolinium ethoxybenzyl diethylenetriamine penta-acetic acid (Gd-EOB-DTPA)-enhanced magnetic resonance cholangiography (MRC) compared with T2-weighted MRC (T2w-MRC) in the detection of biliary leaks.

Methods

Ninety-nine patients with suspected biliary complications underwent routine T2w-MRC and T1w contrast-enhanced (CE) MRC using Gd-EOB-DTPA to identify biliary leaks. Two observers reviewed the image sets separately and together. MRC findings were compared with those of surgery and percutaneous transhepatic cholangiopancreatography. The sensitivity, specificity and accuracy of the techniques in identifying biliary leaks were calculated.

Results

Accuracy of locating biliary leaks was superior with the combination of Gd-EOB-DTPA-enhanced MRC and T2w-MRC (P < 0.05).The mean sensitivities were 79 % vs 59 %, and the mean accuracy rates were 84 % vs 58 % for combined CE-MRC and T2w-MRC vs sole T2w-MRC. Nineteen out of 21 patients with biliary-cyst communication, 90.4 %, and 12/15 patients with post-traumatic biliary extravasations, 80 %, were detected by the combination of Gd-EOB-DTPA-enhanced MRC and T2w-MRC images, P < 0.05.

Conclusions

Gd-EOB-DTPA-enhanced MRC yields information that complements T2w-MRC findings and improves the identification and localisation of the bile extravasations (84 % accuracy, 100 % specificity, P < 0.05). We recommend Gd-EOB-DTPA-enhanced MRC in addition to T2w-MRC to increase the preoperative accuracy of identifying and locating extravasations of bile.

Key Points

• Magnetic resonance cholangiography (MRC) does not always detect bile leakage and cysto-biliary communications.

• Gd-EOB-DTPA-enhanced MRC helps by demonstrating extravasation of contrast material into fluid collections.

• Gd-EOB-DTPA-enhanced MRC also demonstrates the leakage site and bile duct injury type.

• Combined Gd-EOB-DTPA-enhanced and T2w-MRC can provide comprehensive information about biliary system.

• Gd-EOB-DTPA-enhanced MRC is non-invasive and does not use ionising radiation.

The Role of CT cholangiography in the Detection and Localisation of Suspected Bile Leakage Following Cholecystectomy

Background

Most bile duct injuries are not recognized at the time of initial surgery. Optimal treatment requires early recognition. CT IVC has become increasingly important in identifying bile leaks and their source after cholecystectomy. Our study aims to report the outcomes of using CT IVC post operatively and how accurately it can detect or localise bile leaks.

Methods

From 2000 - 2009, twenty patients were managed for suspected bile leak post cholecystectomy within the Alfred Hospital. The study included a retrospective evaluation of the initial procedure, presenting symptoms, site of ductal injury, diagnostic procedures and therapeutic interventions. Results were analysed to determine success of the imaging procedure, and to correlate imaging diagnosis with results both diagnostically and clinically.

Results

Twenty patients had a suspected bile leak, of which 3 were detected at the time of surgery. Seven patients had a CTIVC as their primary investigation. It identified bile leak in 6 and the anatomical site in 5. One had a leak excluded and was managed conservatively.

Conclusions

CT Cholangiography is a feasible and low-risk tool for imaging of the biliary tract in suspected bile leaks post cholecystectomy. It is a valuable non-invasive investigation that may help avoid endoscopic retrograde Cholangiography or surgery.

Contrast-enhanced MR cholangiography (MRCP) with GD-EOB-DTPA in evaluating biliary complications after surgery

PURPOSE

We assessed the usefulness of contrast-enhanced magnetic resonance cholangiography (CE-MRC) with liver-specific contrast agent in evaluating the biliary tree after hepatic surgery.

MATERIALS AND METHODS

A total of 142 patients with suspected biliary complications after liver surgery underwent hepatobiliary MR before and after administration of gadolinium ethoxy benzylic diethylenetriamine pentaacetic acid (Gd-EOB-DTPA). Unenhanced MR cholangiopancreatography (MRCP) and postcontrast MRC were obtained in all patients. Blinded image evaluation and semiquantitative analysis comparing MRCP and CE-MRC were performed by two experienced radiologists.

RESULTS

In all cases, optimal postcontrast visualisation of the biliary tract was obtained. In 22 patients, a postsurgical biliary complication was confirmed. MRCP detected 64% of lesions, but in 36% of cases, an alteration was only suspected but not clearly defined. CE-MRC allowed definite diagnosis in 100% of cases.

CONCLUSIONS

Hepatobiliary-specific contrast agents allow for accurate and extensive study of biliary tract alterations, especially in assessing postsurgical complications.

Endoscopic management of post-cholecystectomy biliary fistula

OBJECTIVE

Bile duct injury is an uncommon but potentially serious complication in cholecystectomy. A recognized treatment for minor biliary injury is internal biliary decompression by endoscopic retrograde cholangiopancreatography (ERCP) and stent insertion. The aim of this study was to assess the effectiveness of ERCP in the management of minor biliary injuries.

METHODS

A retrospective review of medical records at a tertiary referral centre identified 36 patients treated for postoperative minor biliary injuries between 2006 and 2010. Management involved establishing a controlled biliary fistula followed by ERCP to confirm the nature of the injury and decompress the bile duct with stent insertion.

RESULTS

Controlled biliary fistulae were established in all 36 patients. Resolution of the bile leak was achieved prior to ERCP in seven patients, and ERCP with stent insertion was successful in 27 of the remaining 29 patients. Resolution of the bile leak was achieved in all patients without further intervention. The median time to resolution after successful ERCP was 4 days. Two patients underwent ERCP complicated by mild pancreatitis. No other complications were seen.

CONCLUSIONS

This review confirms that postoperative minor biliary injuries can be managed by sepsis control and semi-urgent endoscopic biliary decompression.

Therapeutic induction of hepatic atrophy for isolated injury of the right posterior sectoral duct following laparoscopic cholecystectomy

Laparoscopic cholecystectomy has resulted in various bile duct injuries. Treatment of these injuries is usually difficult and often leads to an intractable clinical course. We herein present a case of isolated right anterior sector (RAS) duct injury induced by laparoscopic cholecystectomy. The bile duct injury was successfully treated by hepatic atrophy induction. Imaging studies revealed that the RAS duct was severed, probably due to rare anatomical variations. Considering the difficulty in surgical reconstruction, atrophy induction of the involved hepatic parenchyma was attempted. This treatment consisted of embolization of the RAS portal branch to inhibit bile production, induction of heavy adhesion at the bile leak site to ensure percutaneous pigtail clamping, and sequential clamping and removal of pigtail catheters. This procedure took 3 months prior to pigtail catheter removal. She was free from other complications during the first 12 months and to date. She will be followed up for 5 years overall including surveillance for hepatobiliary complications. Although this therapeutic induction of atrophy approach is not universally applicable, it can be considered to be a feasible option in unique situations such as this one.

ERCP in the management of biliary complications after cholecystectomy

Open cholecystectomy has been associated historically with 0.2% to 0.5% risk of postoperative biliary injury. Laparoscopic cholecystectomy, which has become the first-line surgical treatment of calculous gallbladder disease, has been associated with a 2.5-fold to fourfold increase in the incidence of postoperative bile duct injury. The biliary endoscopist can expect to see a varied spectrum of complications after cholecystectomy by either technique, including postoperative biliary strictures, bile leaks, and retained calculi in the biliary tree. Proper diagnosis and treatment are paramount in ensuring a satisfactory outcome after bile duct injury. Endoscopic retrograde cholangiopancreatography (ERCP) has become the primary modality for treatment and effectively manages most bile duct injuries.

Iatrogenic biliary injuries: classification, identification, and management

Iatrogenic biliary injuries most commonly occur during laparoscopic cholecystectomy. Biliary injuries are complex problems requiring a multidisciplinary approach with surgeons, radiologists, and gastroenterologists knowledgeable in hepatobiliary disease. Mismanagement can result in lifelong disability and chronic liver disease. Given the unforgiving nature of the biliary tree, favorable outcome requires a well-thought-out strategy and attention to detail.

Spectrum of biliary and nonbiliary complications after laparoscopic cholecystectomy: radiologic findings

OBJECTIVE

The purpose of this article is to illustrate the radiologic features of various biliary and nonbiliary complications after laparoscopic cholecystectomy.

CONCLUSION

Various complications should be considered in patients who do not make an uneventful postoperative recovery after laparoscopic cholecystectomy. Sonography is the easiest and most noninvasive method for screening for such complications. MR cholangiography is most effective in showing biliary complications and CT, for the evaluation of nonbiliary complications. Endoscopic retrograde cholangiography enables not only detailed biliary estimation but also biliary decompression.

MR cholangiopancreatography: 1.5T versus 3T

Soon after its introduction in 1991, MR cholangiopancreatography has become an established diagnostic tool for the evaluation of the pancreaticobiliary ductal system at a field strength of 1.5T. It remains unclear whether MR cholangiopancreatography performed at 3T will benefit from the higher magnetic field strength or whether a field strength of 1.5T should continue to be considered the gold standard for MR cholangiopancreatography. This article reviews the current literature on the benefits and drawbacks of MR cholangiopancreatography at 3T compared with a standard field strength of 1.5T. Field strength-related artifacts that affect MR cholangiopancreatography at 3T also are discussed.

Delayed-onset isolated injury of the right posterior segment duct after laparoscopic cholecystectomy: a report of hepatic segmental atrophy induction

Laparoscopic cholecystectomy resulted in various bile duct injuries. We present an unusual case of right posterior segment (RPS) duct injury detected 35 days after laparoscopic cholecystectomy. Imaging studies revealed that RPS duct was severed probably because of thermal damage from electrocautery. Initially, resection of RPS parenchyma had been planned, but atrophy induction of the involved hepatic parenchyma was attempted because the patient rejected the initial treatment plan. This treatment comprised embolization of RPS portal branch to inhibit bile production, induction of heavy adhesion at the bile leak site to ensure percutaneous transhepatic biliary drainage (PTBD) clamping, and clamping of PTBD tube to accelerate RPS atrophy. This procedure took 4 months before PTBD tube removal. The patient has showed no complications for 30 months to date. Although this atrophy induction approach cannot be regarded as a generally accepted treatment, we believe it can be considered a feasible option in rare circumstances such as this.

Assessment of the optimal temporal window for intravenous CT cholangiography

The optimal temporal window of intravenous (IV) computed tomography (CT) cholangiography was prospectively determined. Fifteen volunteers (eight women, seven men; mean age, 38 years) underwent dynamic CT cholangiography. Two unenhanced images were acquired at the porta hepatis. Starting 5 min after initiation of IV contrast infusion (20 ml iodipamide meglumine 52%), 15 pairs of images at 5-min intervals were obtained. Attenuation of the extrahepatic bile duct (EBD) and the liver parenchyma was measured. Two readers graded visualization of the higher-order biliary branches. The first biliary opacification in the EBD occurred between 15 and 25 min (mean, 22.3 min +/- 3.2) after initiation of the contrast agent. Biliary attenuation plateaued between the 35- and the 75-min time points. Maximum hepatic parenchymal enhancement was 18.5 HU +/- 2.7. Twelve subjects demonstrated poor or non-visualization of higher-order biliary branches; three showed good or excellent visualization. Body weight and both biliary attenuation and visualization of the higher-order biliary branches correlated significantly (P<0.05). For peak enhancement of the biliary tree, CT cholangiography should be performed no earlier than 35 min after initiation of IV infusion. For a fixed contrast dose, superior visualization of the biliary system is achieved in subjects with lower body weight.

Hepatobiliary MRI: current concepts and controversies

Evaluation of the liver and biliary system is a frequent indication for abdominal MRI. Hepatobiliary MRI comprises a set of noninvasive techniques that are usually very effective in answering most clinical questions. There are significant limitations, however, as well as considerable variation and disagreement regarding the optimal protocols for standard hepatic MRI and magnetic resonance cholangiopancreaticography (MRCP). This review discusses pulse sequences most often used in hepatic MRI and MRCP, examines a few sources of controversy in the current literature, and summarizes some recent and future developments in the field.

Magnetic Resonance (MR) Cholangiography

OBJECTIVES

To determine quantitative and qualitative image quality in patients undergoing magnetic resonance (MR) cholangiography at 3.0 Tesla (T) compared with 1.5 T.

MATERIALS AND METHODS

Fifty patients (30 women; mean age, 51 years) underwent MR cholangiography at 1.5 T; another 50 patients (25 women; mean age 51 years) were scanned at 3.0 T. MR sequence protocol consisted of breath-hold single-slice rapid acquisition with relaxation enhancement (RARE) and a respiratory-triggered 3D turbo spin echo (3D TSE) sequence. Maximum intensity projections were generated from the 3D TSE datasets. Contrast-to-noise ratio (CNR) measurements between the common bile duct (CBD), left and right intrahepatic duct (LHD, RHD), and periductal tissue were performed. Three radiologists assessed qualitatively the visibility of the CBD, LHD, and RHD and the overall diagnostic quality.

RESULTS

Mean gain in CNR at 3.0 T versus 1.5 T in all 3 locations ranged for the RARE sequence from 7.7% to 38.1% and for the 3D TSE from 0.5% to 26.1% (P > 0.05 for all differences). Qualitative analysis did not reveal any significant difference between the 2 field strengths (P > 0.05).

CONCLUSIONS

MR cholangiography at 3.0 T shows a trend toward higher CNR without improving image quality significantly.

Value of MRI in three patients with major vascular injuries after laparoscopic cholecystectomy

The aim of this study was to describe three cases of major vascular injuries after laparoscopic cholecystectomy depicted on magnetic resonance (MR) examination. Three female patients (mean age, 32 years; range, 22-39 years) were studied with clinical suspicion of bilio-vascular injuries after laparoscopic cholecystectomy. All MR examinations were performed within 24 h after the laparoscopic procedure. MR imaging was evaluated for major vascular injuries involving the arterial and portal venous system, for bile duct discontinuity, presence or absence of biliary dilation, stricture, excision injury, free fluid and collections. In the first patient, a type-IV Bismuth injury with associated intrahepatic bile ducts dilation was observed. Contrast-enhanced MR revealed lack of enhancement in the right hepatic lobe due to occlusion of the right hepatic artery and the right portal branch. This patient underwent right hepatectomy with hepatico-jejunostomy. In the other two cases, no visualization of the right hepatic artery and the right portal branch was observed on MR angiography. In the first case, the patient underwent right hepatectomy; in the second case, because of stable liver condition, the patient was managed conservatively. MR imaging combined with MR angiography and MR cholangiography can be performed emergently in patients with suspicion of bilio-vascular injury after laparoscopic cholecystectomy allowing the simultaneous evaluation of the biliary tree and the hepatic vascular supply that is essential for adequate treatment planning.

Normal and pathologic features of the postoperative biliary tract at 3D MR cholangiopancreatography and MR imaging

Magnetic resonance (MR) imaging with cholangiopancreatographic sequences plays a critical role in evaluating alterations in the biliary tract after surgical procedures such as cholecystectomy, liver transplantation, hepatic resection, and the creation of a biliary-enteric anastomosis. MR cholangiopancreatography, a rapid, noninvasive, and accurate imaging technique for the assessment of early and late complications of hepatobiliary surgery, usually enables the identification of normal and abnormal postoperative changes. In cases of complete obstruction of the bile duct, MR cholangiopancreatography allows analysis of the biliary tract above and below the level of the obstruction, a capability essential for treatment planning and one that is not provided by either endoscopic retrograde cholangiopancreatography or percutaneous transhepatic cholangiography. MR cholangiopancreatography is particularly useful for the evaluation of biliary-enteric anastomoses, for which an endoscopic approach is generally precluded. It also can help detect and localize bile duct strictures and stones and can help accurately classify bile duct injuries. It is useful for detecting bile leaks, although it generally does not directly depict the extravasation of bile. In addition to MR cholangiopancreatography, T1- and T2-weighted MR imaging may be performed to depict extrabiliary soft-tissue structures and abnormalities such as an abscess, tumor recurrence or metastasis, hematoma, or hemobilia. Mangafodipir trisodium-enhanced MR cholangiopancreatography, a recently developed technique that provides a combination of anatomic and functional information, is particularly helpful for documenting bile leaks because it allows a functional evaluation of biliary excretion and may directly depict bile leakage from injured ducts.

Low conjunction of the cystic duct with the common bile duct: does it correlate with the formation of common bile duct stones?

BACKGROUND

This study aimed to evaluate the accuracy of magnetic resonance cholangiography (MRC) in detecting variants of low cystic duct conjunction, which can be a source of confusion during surgery when unrecognized.

METHODS

All cases with both MRC and endoscopic retrograde cholangiography (ERC) indicating suspected common bile duct stones between January 1999 and January 2004 were retrospectively reviewed by investigators blinded to the final diagnosis. Assessment with ERC was regarded as the gold standard. The aim was to find a low conjunction of the cystic duct with the bile duct. The sensitivity and specificity of MRC were calculated in comparison with those for ERC. The cystic junction radial orientation was defined as lateral (insertion diagonally from the right), medial (insertion into the left side of the common hepatic duct), or posteroanterior (overlap of the junction with the bile duct in the posteroanterior view). A spiral cystic duct and a long parallel course were evaluated separately.

RESULTS

Low insertion of the cystic duct was found on ERC in 66 of 622 patients (11%; 28 men and 38 women; mean age, 64.5 years). The sensitivity and specificity of MRC for detecting low cystic entrance were 100% (90.4% on an intention-to-diagnose basis and 100%, respectively). In 11 patients (16.6%), the radial orientation of the cysticohepatic junction could not be defined with MRC. The rate of correct MRC delineation was 95% for lateral (n = 21), 77% for medial (n = 26), and 74% for posteroanterior (n = 19) insertion of the cystic duct.

CONCLUSION

The findings showed that MRC has good correlation with ERC with regard to the location and anatomic details of cystic duct insertion. Although this does not generate a separate indication for MRC before laparoscopic cholecystectomy, the anatomic information can be of additional use when MRC is clinically indicated in this setting.