Biliary imaging: multimodality approach to imaging of biliary injuries and their complications

A comprehensive exploration of gallbladder health: from common to rare imaging findings

This comprehensive review explores a wide range of imaging findings associated with the gallbladder (GB), from anatomic variants to rare diseases. Through an in-depth review of diagnostic modalities including ultrasound, magnetic resonance cholangiopancreatography, CT, and MRI, we aim to highlight the crucial role of imaging techniques in diagnosing GB disorders, as congenital anomalies, inflammatory diseases, neoplasms, and surgical complications. Employing a detailed analysis and comparison of imaging findings across various modalities, this review seeks to improve diagnostic accuracy for GB-related pathologies, facilitating optimal patient management.

Biliary Leaks: Multidisciplinary Approach to Diagnosis and Treatment

Bile leaks arise from various causes such as trauma, complications after hepatobiliary surgery, and intrahepatic malignancies or their associated liver-directed treatments. Bile leaks can result in significant morbidity and mortality. Delayed diagnosis is not uncommon due to nonspecific manifestations; therefore, a high clinical suspicion is needed. A multidisciplinary approach for treatment of biliary leaks with prompt referral to tertiary care centers with experienced hepatobiliary surgeons, advanced endoscopists, and interventional radiologists is needed to address these challenging complications. Management of biliary leaks can range from conservative management to open surgical repair. Minimally invasive procedures play a crucial role in biliary leak treatment, and the interventional radiologist can help guide appropriate management on the basis of a clear understanding of the pathophysiology of biliary leaks and a current knowledge of the armamentarium of treatment options. In most cases, a simple diversion of bile to decompress the biliary system may prove effective. However, persistent and high-output biliary leaks require delineation of the source with tailored treatment options to control the leak. This may be done by additional diversions, occluding the source, reestablishing connections, or using a combination of therapies to bridge to more definitive surgical interventions. The authors describe the different treatment options and emphasize the role of interventional radiology. ©RSNA, 2024.

Spectrum of Multidetector Computed Tomography Imaging Findings in Iatrogenic Abdominopelvic Injuries: A Comprehensive Pictorial Review

Iatrogenic injuries are unavoidable complications of surgeries and minimally invasive procedures. They are generally classified into vascular and nonvascular injuries and based on the time of injury into early and late injuries. Iatrogenic injuries, particularly vascular injuries, increase the mortality and morbidity, with prolongation of hospital-stay. Multidetector computed tomography (MDCT) is a highly sensitive, and often the first imaging modality in suspected iatrogenic injuries. This pictorial review elucidates the imaging considerations and appearances of iatrogenic injuries of the abdominopelvic organs on MDCT.

Abdominal trauma

Traumatic injuries are the leading cause of death in people aged<45 years, and abdominal trauma is a source of significant morbidity and mortality and high economic costs. Imaging has a fundamental role in abdominal trauma, where CT is a fundamental tool for rapid, accurate diagnosis that will be key for patients' clinical outcomes.

Imaging Features of Main Hepatic Resections: The Radiologist Challenging

Liver resection is still the most effective treatment of primary liver malignancies, including hepatocellular carcinoma (HCC) and cholangiocarcinoma (CCA), and of metastatic disease, such as colorectal liver metastases. The type of liver resection (anatomic versus non anatomic resection) depends on different features, mainly on the type of malignancy (primary liver neoplasm versus metastatic lesion), size of tumor, its relation with blood and biliary vessels, and the volume of future liver remnant (FLT). Imaging plays a critical role in postoperative assessment, offering the possibility to recognize normal postoperative findings and potential complications. Ultrasonography (US) is the first-line diagnostic tool to use in post-surgical phase. However, computed tomography (CT), due to its comprehensive assessment, allows for a more accurate evaluation and more normal findings than the possible postoperative complications. Magnetic resonance imaging (MRI) with cholangiopancreatography (MRCP) and/or hepatospecific contrast agents remains the best tool for bile duct injuries diagnosis and for ischemic cholangitis evaluation. Consequently, radiologists should be familiar with the surgical approaches for a better comprehension of normal postoperative findings and of postoperative complications.

Use of MR in Pancreaticobiliary Emergencies

This article presents the MR protocols, imaging features, diagnostic criteria, and complications of commonly encountered emergencies in pancreaticobiliary imaging, which include pancreatic trauma, bile leak, acute cholecystitis, biliary obstruction, and pancreatitis. Various classifications and complications that can arise with these conditions, as well as artifacts that may mimic pathology, are also included. Finally, the emerging utility of abbreviated MR protocols is discussed.

Multimodality Imaging of Cholecystectomy Complications

Cholecystectomy is one of the most common surgeries performed in the United States. Although complications are uncommon, the high incidence of this surgery means that a radiologist will likely encounter these complications in practice. Complications may arise in the immediate postoperative period or can be delayed for weeks, months, or years after surgery. Vague and nonspecific symptoms make clinical diagnosis challenging. As a result, multimodality imaging is important in postoperative evaluation. US and multidetector CT are the usual first-line imaging modalities. Hepatobiliary scintigraphy, SPECT/CT, and MRI with conventional or gadoxetate hepatobiliary contrast material are important and complementary modalities that are used for workup. The authors begin with a brief discussion of surgical technique and expected postoperative findings and then describe complications organized into four groups: (a) biliary complications, (b) stone-related complications, (c) iatrogenic complications, and (d) gallbladder complications. Biliary complications include bile leaks and bilomas, acute biliary obstruction, and biliary stricture. Stone-related complications include retained and recurrent stones and spillage of stones into the peritoneum. Iatrogenic complications include hemorrhage, vasculobiliary injury, arterial pseudoaneurysms, duodenal injury, and migration of clips. Gallbladder complications include recurrent cholecystitis after subtotal reconstituting cholecystectomy and unexpected gallbladder cancer. An invited commentary by Mullens and Ibrahim is available online. Online supplemental material is available for this article. ^©RSNA, 2022.

Research Priorities in Percutaneous Image and Endoscopy Guided Interventions for Biliary and Gallbladder Diseases: Proceedings from the Society of Interventional Radiology Foundation Multidisciplinary Research Consensus Panel

Recent technological advancements including the introduction of disposable endoscopes have enhanced the role of interventional radiology (IR) in the management of biliary/gallbladder diseases. There are unanswered questions in this growing field. The Society of Interventional Radiology Foundation convened a virtual Research Consensus Panel consisting of a multidisciplinary group of experts, to develop a prioritized research agenda regarding percutaneous image and endoscopy guided procedures for biliary and gallbladder diseases. The panelists discussed current data, opportunities for IR and future efforts to maximize IR's ability and scope. A recurring theme throughout the discussions was to find ways to reduce the total duration of percutaneous drains and to improve the patients' quality of life. Following the presentations and discussions, research priorities were ranked based on their clinical relevance and impact. The research ideas ranked top three were as follows: 1- Percutaneous multimodality management of benign anastomotic biliary strictures (Laser vs endobiliary ablation vs cholangioplasty vs drain upsize protocol alone); 2- Ablation of intraductal cholangiocarcinoma with and without stenting; and 3- Cholecystoscopy/choledochoscopy and lithotripsy in non-surgical patients with calculous cholecystitis. Collaborative retrospective and prospective research studies are essential to answer these questions and to improve the management protocols for patients with biliary/gallbladder diseases.

Imaging Features of Main Posthepatectomy Complications: A Radiologist’s Challenge

In the recent years, the number of liver resections has seen an impressive growth. Usually, hepatic resections remain the treatment of various liver diseases, such as malignant tumors, benign tumors, hydatid disease, and abscesses. Despite technical advancements and tremendous experience in the field of liver resection of specialized centers, there are moderately high rates of postoperative morbidity and mortality, especially in high-risk and older patient populations. Although ultrasonography is usually the first-line imaging examination for postoperative complications, Computed Tomography (CT) is the imaging tool of choice in emergency settings due to its capability to assess the whole body in a few seconds and detect all possible complications. Magnetic resonance cholangiopancreatography (MRCP) is the imaging modality of choice for delineating early postoperative bile duct injuries and ischemic cholangitis that may arise in the late postoperative phase. Moreover, both MDCT and MRCP can precisely detect tumor recurrence. Consequently, radiologists should have knowledge of these surgical procedures for better comprehension of postoperative changes and recognition of the radiological features of various postoperative complications.

The Role of Magnetic Resonance in Evaluating Abdominopelvic Trauma - Part 1: Pancreatic and Hepatobiliary Injuries

Trauma is an important cause of mortality, particularly in the young. While computed tomography (CT) is the mainstay of body imaging in the setting of trauma, magnetic resonance (MR) imaging can be useful in stable patients. Although more commonly used in spinal and musculoskeletal trauma, MR also has a role in abdominopelvic trauma. Broadly, its uses include clarification of equivocal cases, monitoring complications of trauma, particularly with solid organ injury, or as a primary imaging modality for patients with low suspicion for injury for whom avoiding ionizing radiation is a priority-namely, in pediatric and pregnant patients. In this two-part review article, we will review clinical scenarios where this may be encountered, utilizing case examples. This first installment will focus on pancreatic and hepatobiliary injuries. Pancreatic trauma may be difficult to diagnose on CT, and MR may aid in demonstrating pancreatic duct disruption, allowing for accurate grading according to American Association for the Surgery of Trauma (AAST) criteria. It may also be a useful modality for monitoring evolution of pancreatic injuries and/or pseudocyst development, guiding potential stenting, and/or drainage. Biliary injuries are also optimally evaluated with MR, particularly when aided by the use of hepatobiliary contrast material. This can allow for accurate delineation of biliary ductal anatomy and aid in planning percutaneous or endoscopic treatment of bile leaks.

Imaging Evaluation of Living Liver Donor Candidates: Techniques, Protocols, and Anatomy

The need for liver transplants is increasing because the prevalence of liver diseases and the indications for transplants are growing. In response to the shortage of grafts from deceased donors, more transplants are being performed worldwide with grafts from living donors. Radiologic evaluation is an integral component in the assessment of donor candidates to ensure their eligibility and to choose the most appropriate surgical approach. MRI is the preferred modality for evaluation of the liver parenchyma and biliary tree. In most centers, a combination of MRI and CT is used to take advantage of the higher spatial resolution of CT for evaluation of arteries. However, MRI-only assessment is feasible. In addition to assessment of the liver parenchyma for abnormalities such as steatosis, a detailed evaluation of the hepatic vascular and biliary system for pertinent anatomic variants is crucial, because these variants can affect surgical techniques and outcomes in both recipients and donors. In this pictorial article, after a brief review of the most common surgical techniques and postsurgical liver anatomy, the biliary and vascular anatomy are discussed, with specific attention paid to the variants that are pertinent to this surgical procedure. The roles of liver segmentation and volumetric assessment and current imaging techniques and protocols are also discussed. Online supplemental material is available for this article. ©RSNA, 2021.

Noninvasive Imaging Prior to Biliary Interventions

Noninvasive imaging is a crucial and initial step in the diagnostic algorithm of patients with suspected biliary pathology and directs the subsequent diagnostic and therapeutic workup, including the endoluminal and percutaneous biliary interventions. This article reviews the current noninvasive imaging methods for the evaluation of biliary system and further discusses their roles in the diagnostic workup of different biliary disease.

Modern imaging of cholangitis

Cholangitis refers to inflammation of the bile ducts with or without accompanying infection. When intermittent or persistent inflammation lasts 6 months or more, the condition is classified as chronic cholangitis. Otherwise, it is considered an acute cholangitis. Cholangitis can also be classified according to the inciting agent, e.g. complete mechanical obstruction, which is the leading cause of acute cholangitis, longstanding partial mechanical blockage, or immune-mediated bile duct damage that results in chronic cholangitis.The work-up for cholangitis is based upon medical history, clinical presentation, and initial laboratory tests. Whereas ultrasound is the first-line imaging modality used to identify bile duct dilatation in patients with colicky abdominal pain, cross-sectional imaging is preferable when symptoms cannot be primarily localised to the hepatobiliary system. CT is very useful in oncologic, trauma, or postoperative patients. Otherwise, magnetic resonance cholangiopancreatography is the method of choice to diagnose acute and chronic biliary disorders, providing an excellent anatomic overview and, if gadoxetic acid is injected, simultaneously delivering morphological and functional information about the hepatobiliary system. If brush cytology, biopsy, assessment of the prepapillary common bile duct, stricture dilatation, or stenting is necessary, then endoscopic ultrasound and/or retrograde cholangiography are performed. Finally, when the pathologic duct is inaccessible from the duodenum or stomach, percutaneous transhepatic cholangiography is an option. The pace of the work-up depends upon the severity of cholestasis on presentation. Whereas sepsis, hypotension, and/or Charcot's triad warrant immediate investigation and management, chronic cholestasis can be electively evaluated.This overview article will cover the common cholangitides, emphasising our clinical experience with the chronic cholestatic liver diseases.

Role of MRI in early follow-up of patients with solid organ injuries: How and why we do it?

Trauma represents one of the most common causes of death or permanent disability in the population below 50 years. At present, non-operative treatment is the commonly adopted strategy in hemodynamically stable patients with solid organ injuries, when there are not concomitant bowel and mesenteric injuries requiring a prompt surgical approach, but it may require multiple imaging follow-up examinations, especially in the case of major injuries. No data are available about magnetic resonance imaging utilization in the early follow-up of trauma patients with solid organ injuries, particularly in liver and spleen trauma. We report our preliminary experience in this field.

Problem-solving with MRI in acute abdominopelvic conditions, part 1: gastrointestinal, hepatobiliary, and pancreatic diseases

The purpose of this article is to review the benefit and added value and advantages of magnetic resonance imaging (MRI) compared with other cross-sectional imaging in patients presenting with abdominopelvic emergencies. During the past decade, there has been increased utilization of MRI in the emergency department with widespread availability of MR scanners, improvement in rapid imaging techniques, and methods to overcome motion-related artifacts. This has benefited patients at higher risk of radiation, particularly children and pregnant women, and patients with contraindications to iodinated contrast including allergy and renal dysfunction. Still the challenges are: on site MR scanner in the emergency department, after-hour services, as well as availability of time slot to rapidly scan emergency patient. MRI has additional advantages over other imaging modalities due to its high contrast resolution, which allows it to better characterize tissue and fluid collections, and may avoid the need for intravenous contrast. Radiologists must be familiar with the role and added value of MRI, spectrum of imaging findings, and problem-oriented modified MR protocols in abdominal and pelvic emergencies. In part 1, we will discuss the utility of MRI in gastrointestinal, hepatobiliary, and pancreatic diseases. In part 2, the authors will focus on the key MR imaging features of female pelvic gynecological diseases, pregnancy related complications, abdominal vascular complications, and renal diseases.

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.

Hepatobiliary Injuries: A Pictoral Essay and Literature Review

Injuries to the liver and biliary tree carry significant morbidity and mortality if not diagnosed and managed rapidly. As clinical evaluation of suspected hepatobiliary injury is often limited in traumatic or post-surgical settings, imaging plays a critical role in the diagnosis of injury, assessment of treatment response and detection of delayed complications. In this paper, we review acute traumatic and iatrogenic hepatobiliary injuries and subsequent complications through different imaging modalities.

Spontaneous bronchobiliary fistula: Case report

Bronchobiliary fistula (BBF) is a rare condition that results from the communication between the bile ducts and the bronchial tree. It is characterized by the presence of bile in the sputum as pathognomonic symptom, and it is often associated with suspicious pneumonia. The most common causes include infections (e.g. echinococcosis), hepatobiliary surgery, blunt torso traumas, tumors and percutaneous transhepatic procedures. Opinions about BBF treatment are still controversial as it can be treated by both conservative and surgical procedures, while pharmacological treatments are only rarely used. This case report presents a patient who had been diagnosed with chronic BBF of unknown cause, underwent several ineffective conservative procedures and was at last surgically treated.

Changes in Approach to Solid Organ Injury: What the Radiologist Needs to Know

This review aims to examine the challenges facing radiologists interpreting trauma computed tomography (CT) images in this era of a changing approach to management of solid organ trauma. After reviewing the pearls and pitfalls of CT imaging protocols for detection of traumatic solid organ injuries, we describe the key changes in the 2018 American Association for the Surgery of Trauma Organ Injury Scales for liver, spleen, and kidney and their implications for management strategies. We then focus on the important imaging findings in observed in patients who undergo nonoperative management and patients who are imaged post damage control surgery.

Duodeno-pancreatic and extrahepatic biliary tree trauma: WSES-AAST guidelines

Duodeno-pancreatic and extrahepatic biliary tree injuries are rare in both adult and pediatric trauma patients, and due to their anatomical location, associated injuries are very common. Mortality is primarily related to associated injuries, but morbidity remains high even in isolated injuries. Optimal management of duodeno-bilio-pancreatic injuries is dictated primarily by hemodynamic stability, clinical presentation, and grade of injury. Endoscopic and percutaneous interventions have increased the ability to non-operatively manage these injuries. Late diagnosis and treatment are both associated to increased morbidity and mortality. Sequelae of late presentations of pancreatic injury and complications of severe pancreatic trauma are also increasingly addressed endoscopically and with interventional radiology procedures. However, for moderate and severe extrahepatic biliary and severe duodeno-pancreatic injuries, immediate operative intervention is preferred as associated injuries are frequent and commonly present with hemodynamic instability or peritonitis. The aim of this paper is to present the World Society of Emergency Surgery (WSES) and American Association for the Surgery of Trauma (AAST) duodenal, pancreatic, and extrahepatic biliary tree trauma management guidelines.

Imaging of Abdominal Postoperative Complications

We present a case-based review of abdominal postoperative complications, organized by organ system affected, including wound/superficial, hepatobiliary, pancreatic, gastrointestinal, genitourinary, and vascular complications. Both general complications and specific considerations for certain types of operations are described, as well as potential pitfalls that can be confused with complications. Representative cases are shown using all relevant imaging modalities, including CT, fluoroscopy, ultrasound, MRI, and nuclear medicine. Management options are also described, highlighting those that require radiologist input or intervention.

Gd-EOB-DTP-enhanced MRC in the preoperative percutaneous management of intra and extrahepatic biliary leakages: does it matter?

Postoperative bile leakage is a common complication of abdominal surgical procedures and a precise localization of is important to choose the best management. Many techniques are available to correctly identify bile leaks, including ultrasound (US), computed tomography (CT) or magnetic resonance imaging (MRI), being the latter the best to clearly depict "active" bile leakages. This paper presents the state of the art algorithm in the detection of biliary leakages in order to plan a percutaneous biliary drainage focusing on widely available and safe contrast agent, the Gb-EOB-DPA. We consider its pharmacokinetic properties and impact in biliary imaging explain current debates to optimize image quality. We report common sites of leakage after surgery with special considerations in cirrhotic liver to show what interventional radiologists should look to easily detect bile leaks.

Ascites relative enhancement during hepatobiliary phase after Gd-BOPTA administration: a new promising tool for characterising abdominal free fluid of unknown origin

OBJECTIVES

To correlate the degree of ascites enhancement during hepatobiliary phase after gadobenate dimeglumine (Gd-BOPTA) administration with ascites aetiology.

METHODS

IRB-approved retrospective study, need for informed consent was waived. We included 74 consecutive ascitic patients who underwent Gd-BOPTA-enhanced liver MRI including hepatobiliary phase (HBP) images between January 2014 and December 2017. Ascites appearance on unenhanced and HBP images was classified as hypo-, iso- or hyperintense in comparison to paraspinal muscles. Ascites signal intensity on unenhanced and HBP images was measured using round ROIs and was normalised to paraspinal muscles (NSI). Normalised relative enhancement (NRE) between native phase and HBP was calculated. The results were related to ascites aetiology using Wilcoxon and Mann-Whitney tests.

RESULTS

On native images, ascites appeared hypointense in 95.9% of the cases and isointense in 4.1%, whereas on HBP images, it appeared hyperintense in 59.4% of the cases, isointense in 36.5% and hypointense in 4.1%. Mean ascites NSI was 0.52 on unenhanced images and 1.50 on HBP ones (p < 0.0001). Mean ascites NRE was 201 ± 133%. Ascites of non-malignant aetiology showed mean NRE of 210 ± 134%, whereas malignant ascites showed mean NRE of 92 ± 20% (p = 0.001). ROC analysis showed that a NRE < 112.5% correlates with malignant aetiology with 100% sensitivity and 83.4% specificity (LR = 5.667). NRE did not show any significant correlation with ascites thickness, eGFR and time interval between contrast administration and HBP acquisition (p > 0.05).

CONCLUSIONS

Ascites NRE in HBP after Gd-BOPTA administration is significantly lower in patients with ascites secondary to peritoneal carcinomatosis than in patients with non-malignant ascites.

KEY POINTS

• Ascites enhancement in the hepatobiliary phase after Gd-BOPTA administration may determine false positive findings when looking for biliary leaks. • Ascites enhancement in the hepatobiliary phase after Gd-BOPTA administration is lower in patients with peritoneal carcinomatosis than in patients with portal hypertension or congestive heart failure. • None of the patients with peritoneal carcinomatosis showed an ascites enhancement of more than 112% as compared with unenhanced images.

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.

Pancreaticobiliary Trauma: A Multimodality Imaging Update

Pancreaticobiliary injury is an uncommon entity which more often occurs in the setting of blunt than penetrating trauma. We present cases of pancreaticobiliary traumatic injuries from our Level 1 trauma center to illustrate an imaging update on the spectrum of injuries and correlation with current grading systems.

Major pancreatic resections: normal postoperative findings and complications

Objectives

(1) To illustrate and describe the main types of pancreatic surgery; (2) to discuss the normal findings after pancreatic surgery; (3) to review the main complications and their radiological findings.

Background

Despite the decreased postoperative mortality, morbidity still remains high resulting in longer hospitalisations and greater costs. Imaging findings following major pancreatic resections can be broadly divided into “normal postoperative alterations” and real complications. The former should regress within a few months whereas complications may be life-threatening and should be promptly identified and treated.

Imaging findings

CT is the most effective postoperative imaging technique. MRI and fluoroscopy are used less often and only in specific cases such as assessing the gastro-intestinal function or the biliary tree. The most common normal postoperative findings are pneumobilia, perivascular cuffing, fluid collections, lymphadenopathy, acute anastomotic oedema and stranding of the peri-pancreatic/mesenteric fat. Imaging depicts the anastomoses and the new postoperative anatomy. It can also demonstrate early and late complications: pancreatic fistula, haemorrhage, delayed gastric emptying, hepatic infarction, acute pancreatitis of the remnant, porto-mesenteric thrombosis, abscess, biliary anastomotic leaks, anastomotic stenosis and local recurrence.

Conclusions

Radiologists should be aware of surgical procedures, postoperative anatomy and normal postoperative imaging findings to better detect complications and recurrent disease.

Teaching Points

• Morbidity after pancreatic resections is high.

• CT is the most effective postoperative imaging technique.

• Imaging depicts the anastomoses and the new postoperative anatomy.

• Pancreatic fistula is the most common complication after partial pancreatic resection.

Acute Abdomen Secondary to a Spontaneous Perforation of the Biliary Tract, a Rare Complication of Choledocholithiasis

INTRODUCTION

The spontaneous perforation of the biliary tract (SPBT) is an extremely rare cause of peritonitis, which was first described by Freeland in 1982, to date only around 70 cases have been reported. Here we present a case of spontaneous perforation of the biliary tract, in a patient with choledocholithiasis, which was treated with ultrasound-guided drainage and ERCP.

CASE REPORT

A 51-year-old male was admitted to the emergency room for 15-day evolution jaundice, localized pain in the right flank and hypochondrium of 3days. He had a history of cholecystectomy 15 years ago and 4 episodes of cholangitis, the last one in 2015. A magnetic resonance imaging (MRI) was performed, that showed evidence of choledocholithiasis, in addition to a possible biliary leakage. The patient was treated with ultrasound-guided drainage and ERCP successfully.

DISCUSSION

Spontaneous perforation of the biliary tract is a disease entity in which wall of the extrahepatic or intrahepatic duct is perforated without any traumatic or iatrogenic injury. The clinical presentation varies from nonspecific abdominal pain to biliary peritonitis, in most of the cases forming bilomas. Universal management involves decompression of the biliary tree and repair of the leak site.

CONCLUSION

The spontaneous perforation of the biliary tract is a disease that represents a diagnostic challenge. The treatment in the patients with SPBT is not well established and has to be individualized for each case, depending on the history of the patient, the site of perforation, the time of evolution, the suspicion of infection, and the patient status.

Evaluation of biliary ductal anatomy in potential living liver donors: comparison between MRCP and Gd-EOB-DTPA-enhanced MRI

PURPOSE

To compare magnetic resonance cholangiopancreatography (MRCP) and Gd-EOB-DTPA-enhanced MRI in the evaluation of the biliary anatomy in potential living liver donors (LLDs).

METHODS

A retrospective study was conducted in a tertiary care liver transplant center after obtaining ethics and institutional approvals. A total of 42 potential LLD MRI examinations were performed between November 2013 and March 2016. All patients underwent a standard MRI protocol which included MRCP and Gd-EOB-DTPA-enhanced MRI sequences in a single session. Three abdominal MR radiologists independently reviewed the studies and completed a customized data collection sheet for each MR sequence. The readers subjectively scored the bile duct visualization on each MR sequence on a Likert scale and classified the biliary anatomic configuration. Statistical analysis was performed using intraclass correlation coefficient and the McNemar Chi-square (χ ²) test.

RESULTS

The 42 potential LLDs included 22 males and 20 females with an age range of 18-60 years. There was 'good' or 'excellent' inter-reader agreement on either MRI examination for the visualization of the first- and second-order ducts and the majority of third-order ducts. 'Good' inter-reader agreement on Gd-EOB-DTPA-enhanced MRI and 'fair' inter-reader agreement on MRCP was noted for the left third-order medial duct. There was significantly better visualization of the cystic duct, left hepatic duct, and right second-order ducts on Gd-EOB-DTPA-enhanced MRI compared with MRCP. A 12.6% improvement in classifying the biliary branch pattern was also observed on Gd-EOB-DTPA-enhanced MRI compared with MRCP (P = 0.03).

CONCLUSION

Gd-EOB-DTPA-enhanced MRI provides additional diagnostic confidence over MRCP in the evaluation of the biliary ductal anatomy in potential LLDs.

Anatomical Variations of the Biliary Tree Found with Endoscopic Retrograde Cholagiopancreatography in a Referral Center in Southern Iran

BACKGROUND

Anatomical variations in the biliary system have been proven to be of clinical importance. Awareness of the pattern of these variations in a specific population may help to prevent and manage biliary injuries during surgical and endoscopic procedures. Knowledge of the biliary anatomy will be also of great help in planning the drainage of adequate percentage of liver parenchyma in endoscopic or radiological procedures.

METHODS

All consecutive patients undergoing endoscopic retrograde cholangiopancreatography (ERCP) from April 2013 to April 2015 at Nemazee Hospital, a referral center in the south of Iran, were included in this cross-sectional study. The patients with previous hepatic or biliary surgery, liver injury or destructive biliary disease were excluded from the study. All ERCPs were reviewed by two expert gastroenterologists in this field. The disagreed images by the two gastroenterologists were excluded. Huang classification was used for categorizing the different structural variants of the biliary tree, and the frequency of each variant was recorded.

RESULTS

Totally, 362 patients (181 men and 181 women) were included in the study. 163 patients (45%) had type A1 Huang classification (right dominant), which was the most prevalent type among our patients. 55% of them had non-right dominant anatomy. The result of the Chi-square test revealed that there was no statistically significant difference between the men and women regarding the anatomical variations (p = 0.413).

CONCLUSION

The anatomical variation in the biliary system among Iranian patients is comparable to other regions of the world. Significant proportions of our patients are non-right dominant and may need bilateral biliary drainage.

Abdominal cross-sectional imaging of the associating liver partition and portal vein ligation for staged hepatectomy procedure

Associating liver partition and portal vein ligation for staged hepatectomy (ALPPS) is a recently introduced technique aimed to perform two-stage hepatectomy in patients with a variety of primary or secondary neoplastic lesions. ALPSS is based on a preliminary liver resection associated with ligation of the portal branch directed to the diseased hemiliver (DH), followed by hepatectomy after an interval of time in which the future liver remnant (FLR) hypertrophied adequately (partly because of preserved arterialization of the DH). Multidetector computed tomography (MDCT) and magnetic resonance imaging (MRI) play a pivotal role in patients’ selection and FLR assessment before and after the procedure, as well as in monitoring early and late complications, as we aim to review in this paper. Moreover, we illustrate main abdominal MDCT and MRI findings related to ALPPS.

Iatrogenic, blunt, and penetrating trauma to the biliary tract

Iatrogenic and traumatic bile leaks are uncommon. However, given the overall increase in number of hepatobiliary surgeries and the paradigm shift toward nonoperative management of patients with liver trauma, they have become more prevalent in recent years. Imaging is essential to establishing early diagnosis and guiding treatment as the clinical signs and symptoms of bile leaks are nonspecific, and a delay in recognition of bile leaks portends a high morbidity and mortality rate. Findings suspicious for a bile leak at computed tomography or ultrasonography include free or contained peri- or intrahepatic low density fluid in the setting of recent trauma or hepatobiliary surgery. Hepatobiliary scintigraphy and magnetic resonance cholangiopancreatography (MRCP) with hepatobiliary contrast agents can be used to detect active or contained bile leak. MRCP with hepatobiliary contrast agents has the unique ability to reveal the exact location of bile leak, which often governs whether endoscopic management or surgical management is warranted. Percutaneous transhepatic cholangiography and fluoroscopy via an indwelling catheter that is placed either percutaneously or surgically are useful modalities to guide percutaneous transhepatic biliary drain placement which can provide biliary drainage and/or diversion in the setting of traumatic biliary injury. Surgical treatment of a bile duct injury with Roux-en-Y hepaticojejunostomy is warranted if definitive treatment cannot be accomplished through percutaneous or endoscopic means.

Diagnosis and Management of Postoperative Biliary Leaks

Postoperative biliary leaks have become more common in the past three decades since the development of laparoscopic biliary surgery. The role of the radiologist and interventional radiologist is important in the diagnosis and treatment of such complications, and can play an adjunctive role in the definitive surgical repair. Ultrasound, computed tomography, magnetic resonance cholangiopancreatography, nuclear medicine cholescintigraphy studies, and percutaneous transhepatic cholangiograms (PTC) are the various imaging modalities used for diagnosis. Interventional radiology treatment involves percutaneous drainage of bilomas, characterization of the biliary tree and assessment of the site of ductal injury with PTC, and biliary diversion with external biliary drainage.

Imaging of the postoperative liver: review of normal appearances and common complications

Several benign and malignant liver diseases may require surgical treatment for cure, including anatomical resections based on the segmental anatomy of the liver, non-anatomical (wedge) resections, and surgical management of biliary cysts. The type of surgery depends not only on the location and the nature of the disease, but also on the expertise of the surgeon. Whereas ultrasonography is often the first-line imaging examination in case of suspected postoperative complication, multidetector computed tomography (MDCT) is of greater value for identifying normal findings after surgery, early postoperative pathologic fluid collections and vascular thromboses, and tumor recurrence in patients who have undergone hepatic surgery. Magnetic resonance cholangiopancreatography (MRCP) is the imaging modality of choice for depicting early postoperative bile duct injuries and ischemic cholangitis that may occur in the late postoperative phase. Both MDCT and MRCP can accurately depict tumor recurrence. Radiologists should become familiar with these surgical procedures to better understand postoperative changes, and with the normal imaging appearances of various postoperative complications to better differentiate between complications and normal findings.

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.