Imaging of Biliary Tree Abnormalities

Pathologic conditions of the biliary system, although common, can be difficult to diagnose clinically. Challenges in biliary imaging include anatomic variants and the dynamic nature of the biliary tract, which can change with age and intervention, blurring the boundaries of normal and abnormal. Choledochal cysts can have numerous appearances and are important to diagnose given the risk of cholangiocarcinoma potentially requiring surgical resection. Choledocholithiasis, the most common cause of biliary dilatation, can be difficult to detect at US and CT, with MRI having the highest sensitivity. However, knowledge of the imaging pitfalls of MRI and MR cholangiopancreatography is crucial to avoid misinterpretation. Newer concepts in biliary tract malignancy include intraductal papillary biliary neoplasms that may develop into cholangiocarcinoma. New paradigms in the classification of cholangiocarcinoma correspond to the wide range of imaging appearances of the disease and have implications for prognosis. Accurately staging cholangiocarcinoma is imperative, given expanding curative options including transplant and more aggressive surgical options. Infections of the biliary tree include acute cholangitis or recurrent pyogenic cholangitis, characterized by obstruction, strictures, and central biliary dilatation. Inflammatory conditions include primary sclerosing cholangitis, which features strictures and fibrosis but can be difficult to differentiate from secondary causes of sclerosing cholangitis, including more recently described entities such as immunoglobulin G4-related sclerosing cholangitis and COVID-19 secondary sclerosing cholangitis. The authors describe a wide variety of benign and malignant biliary tract abnormalities, highlight differentiating features of the cholangitides, provide an approach to interpretation based on the pattern of imaging findings, and discuss pearls and pitfalls of imaging to facilitate accurate diagnosis. ©RSNA, 2024 Supplemental material is available for this article.

Traveling gallstones: review of MR imaging and surgical pathology features of gallstone disease and its complications in the gallbladder and beyond

Gallstone-related disease comprises a spectrum of conditions resulting from biliary stone formation, leading to obstruction and inflammatory complications. These can significantly impact patient quality of life and carry high morbidity if not accurately detected. Appropriate imaging is essential for evaluating the extent of gallstone disease and assuring appropriate clinical management. Magnetic Resonance Imaging (MRI) techniques (including Magnetic Resonance Cholangiopancreatography (MRCP) are increasingly used for diagnosis of gallstone disease and its complications and provide high contrast resolution and facilitate tissue-level assessment of gallstone disease processes. In this review we seek to delve deep into the spectrum of MR imaging in diagnose of gallstone-related disease within the gallbladder and complications related to migration of the gallstones to the gall bladder neck or cystic duct, common hepatic duct or bile duct (choledocholithiasis) and beyond, including gallstone pancreatitis, gallstone ileus, Bouveret syndrome, and dropped gallstones, by offering key examples from our practice. Furthermore, we will specifically highlight the crucial role of MRI and MRCP for enhancing diagnostic accuracy and improving patient outcomes in gallstone-related disease and showcase relevant surgical pathology specimens of various gallstone related complications.

CT and MR imaging of primary biliary cholangitis: a pictorial review

Primary biliary cholangitis (PBC) is a rare chronic autoimmune-mediated cholestatic liver disease involving medium and small bile ducts that can lead to liver fibrosis and cirrhosis. To date, the pathogenesis of PBC remains elusive, and there is currently no curative medical treatment. Computed tomography (CT) and magnetic resonance (MR) imaging, as common technical tools that allow non-invasive monitoring of liver tissue in vivo, play crucial roles in the diagnosis, staging, and prognosis prediction in PBC by enabling assessment of abnormalities in liver morphology and parenchyma, irregular configuration of bile ducts, lymphadenopathy, portal hypertension, and complications of cirrhosis. Moreover, CT and MRI can be used to monitor the disease progression after treatment of PBC (e.g. the onset of cirrhotic decompensation or HCC) to guide the clinical decisions for liver transplantation. With the optimization of imaging technology, magnetic resonance elastography (MRE) offers additional information on liver stiffness, allows for the identification of early cirrhosis in PBC and provides a basis for predicting prognosis. Gadoxetic acid-enhanced MRI enables the assessment of liver function in patients with PBC. The purpose of this review is to detail and illustrate the definition, pathological basis, and clinical importance of CT and MRI features of PBC to help radiologists and clinicians enhance their understanding of PBC.Critical Relevance StatementCharacteristic CT and MR imaging manifestations of primary biliary cholangitis may reflect the course of the disease and provide information associated with histological grading and altered cellular function.Key points• Imaging has become highly useful for differentiating PBC from other diseases.• Key pathological alterations of PBC can be captured by CT and MRI.• Characteristic manifestations provide information associated with histological grade and cellular function.• Despite this, the CT or MRI features of PBC are not specific.

Comparison of MRCP and ERCP in the evaluation of common bile duct and pancreatic duct pathologies

Background

Magnetic resonance cholangiopancreatography (MRCP) is a non-invasive imaging modality that has high diagnostic accuracy for a wide range of bile duct and pancreatic duct pathologies. Endoscopic retrograde cholangiopancreatography (ERCP) is still the gold standard for the exploration of the biliopancreatic region.

Aim

The aim of the study was to compare the diagnostic accuracy of MRCP with that of ERCP in the diagnosis of bile duct and pancreatic duct pathologies.

Material and methods

A total of 60 patients with common bile duct (CBD) and pancreatic duct pathologies detected on MRCP were subsequently evaluated by ERCP in this observational study. A comparison of MRCP findings with ERCP was made.

Results

MRCP had a sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of 88.1%, 94.4%, 97.3%, 72.7%, and 90%, respectively, in diagnosing choledocholithiasis in comparison to ERCP. For CBD dilation, the sensitivity was 90.91%, specificity was 93.75% and the PPV, NPV, and accuracy were 97.56%, 78.95%, and 91.67%, respectively, for MRCP. In CBD stricture, MRCP showed a sensitivity, specificity, PPV, NPV, and accuracy of 83.33%, 97.92%, 90.91%, 95.92%, and 95%, respectively. In pancreatic duct dilatation, the sensitivity, specificity, PPV, NPV, and accuracy were all 100%. Pancreatic duct stricture showed a sensitivity, specificity, PPV, NPV, and accuracy of 80%, 98%, 88.89%, 96.08%, and 95%, respectively. For the diagnosis of periampullary carcinoma, the sensitivity, specificity, PPV, NPV, and accuracy rate of MRCP were 80%, 98%, 88.89%, 96.08%, and 95%, respectively.

Conclusion

No significant difference was found between MRCP and ERCP in diagnosing those six pathologies.

ACCURACY OF ABBREVIATED PROTOCOL OF MAGNETIC RESONANCE CHOLANGIO-PANCREATOGRAPHY IN THE DIAGNOSIS OF CHOLEDOCHOLITHIASIS

BACKGROUND

Abbreviated magnetic resonance imaging protocols have emerged to reduce the examination time of the long protocols eliminating unnecessary pulse sequences to answer a targeted clinical question, without compromising diagnostic information.

OBJECTIVE

The objective of this study was to evaluate the diagnostic accuracy of an abbreviated magnetic resonance cholangiopancreatography (A-MRCP) protocol in patients with suspected choledocholithiasis.

METHODS

This retrospective study evaluated patients (ages 10 + years) that performed consecutive MRCP examination from October 2019 to June 2020, with the clinical suspicion of choledocholithiasis. Readers first evaluated the biliary tree using a four-sequence A-MRCP protocol and later reviewed the entire conventional eleven-sequence MRCP. Presence of choledocholithiasis, stone size, common bile duct caliber, and additional findings were evaluated.

RESULTS

A total of 148 patients with MRCP were included (62.8% female, mean 50.9 years). The prevalence of choledocholithiasis was 32.2%. The accuracy of the abbreviated MRCP protocol for choledocholithiasis was 98.7%. There was no difference between the performance of the abbreviated and conventional MRCP image sets for detection of choledocholithiasis (kappa=0.970), with a sensitivity of 98% and a specificity of 99%. There was excellent inter-reader agreement evaluating for choledocholithiasis on both imaging sets of MRCP protocols (kappa values were 0.970).

CONCLUSION

An abbreviated MRCP protocol to evaluate for choledocholithiasis provides similar diagnostic over the conventional MRCP protocol, offering potential for decreased scanning time and improved patient tolerability.

Hepatobiliary Excretion PET/CT With 68Ga-TAoS-DAZA to Evaluate Bile Duct Patency

ABSTRACT

Tri-alkoxysalicyl-1,4-diazepan-6-amine (TAoS-DAZA) ligands, radiolabelled with 68Ga, have been proposed as PET/CT agents for depiction and quantification of hepatobiliary function and evaluation of bile excretion. In the presented case, a patient with hepatocellulary carcinoma underwent PET/CT with the TAoS-derivate 68Ga-tri-methoxysalicyl-(TMoS)-DAZA to determine the patency of intrahepatic and extrahepatic bile ducts, in particular of a stent in the common bile duct. The PET/CT was performed without complications. Evaluation of bile excretion over time was possible. 68Ga-TAoS-DAZA PET/CT may be an option for dynamic imaging of the excretory hepatic function to visualize the biliary tree and to rule out cholestasis.

Effect of Ageing on the Common Bile Duct Diameter

INTRODUCTION

The aim of the study was to determine if the common bile duct (CBD) diameter increases physiologically with age and investigate whether gallstones lead to changes in CBD diameter.

METHOD

Our study is composed of 721 patients in 2 groups: 517 asymptomatic patients and 204 gallstones patients who underwent MRCP. Their CBD diameter was measured at its widest visible portion on MRCP. Simple linear regression of the average of these measurements was used to investigate the relationship between age and CBD diameter in both populations. Subjects were further divided into 8 subgroups age-wise, respectively, and their means compared decade-wise using ANOVA. Furthermore, each subgroup mean from both populations was compared with each other using a t test.

RESULTS

Among the 517 subjects, the mean CBD diameter was 5.3663 mm ± 1.43546 and correlated with age (p < 0.01), dilating at 0.07 mm/year. The mean diameter of our oldest group was 7.9 mm, resulting in a plausible upper limit of 8 mm for the asymptomatic population. The mean CBD diameter of the cholelithiasis population was 5.6738 mm ± 1.40986 and also correlated with age (p < 0.01). The mean CBD diameter of the age groups from the cholelithiasis population was larger than that from the asymptomatic population, but none were statistically significant.

CONCLUSION

Although the CBD increases physiologically with age, there is no significant difference in CBD size between the general population and the cholelithiasis patients at any particular age. Gallstones do not independently dilate the CBD.

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.

Occult Perforated Gangrenous Gallbladder Found on Magnetic Resonance Cholangiopancreatography

Acute gangrenous cholecystitis is a life-threatening disease that is most often diagnosed intraoperatively and can be missed on mildly symptomatic patients without the proper imaging modality. We present a case of a 69-year-old male with a history of hypertension, hyperlipidemia, and type 2 diabetes, and a recent right pontine infarct that arrived with 3 out of 10 right-sided abdominal pain. His liver ultrasound and computed tomography (CT) with contrast demonstrated acute cholecystitis. He was initially worked up conservatively and was scheduled for an elective cholecystectomy per surgery recommendation. However erring on the side of caution, the medical team had ordered a magnetic resonance cholangiopancreatography (MRCP), which demonstrated perforated gangrenous cholecystitis. Of note, the imaging modalities were ordered within a 24-hour window. The patient's antibiotics were promptly broadened, and he was emergently sent to the operating room. Moving forward, we will identify atypical clinical presentations of gangrenous cholecystitis and consider ordering an MRCP when clinical suspicion remains high and initial imaging is inconclusive. Perforated gangrenous cholecystitis is a severe disease and can cause rapid demise if not identified and treated early.

Hemorrhagic cholecystitis: ultrasound and CT imaging findings-a retrospective case review series

PURPOSE

Gallbladder pathology is diverse, and imaging tests are essential tools for its diagnosis. Acute cholecystitis has multiple manifestations or complications, one of which is hemorrhagic cholecystitis (HC). In the current literature, this pathology has been described only in the spectrum of acute cholecystitis complications, case reports, or series with a maximum of 2 to 3 cases. After a retrospective review, we present 11 cases of hemorrhagic cholecystitis and discuss its various causes, clinical presentations, and findings on ultrasound (US) and computed tomography (CT), considering dual-energy CT and magnetic resonance imaging (MRI).

METHODS

A retrospective review of 6 years (2012-2018) of hemorrhagic cholecystitis cases diagnosed at our hospital was performed. A search engine of medical terms was used and the database of radiological cases in the emergency department of the hospital. After a careful review by two emergency and one abdominal radiologists, 11 patients were identified as hemorrhagic cholecystitis cases according to their clinical, radiological, and surgical records and confirmed with pathology reports.

RESULTS

Both lithiasis and anticoagulation/antiplatelet therapy were the most common etiologies found (9 patients, 82%). The clinical presentation may be misleading, simulating a usual cholecystitis episode with abdominal pain, nausea, and vomiting, or manifesting with signs of bile duct obstruction, hematemesis, or anemia that may compromise the patient hemodynamically and become fatal. US is useful, but CT is the most complete test for evaluating hemorrhagic cholecystitis and was performed in all the patients. The common findings were inflammatory changes in all patients (100%), hemobilia in 10 patients (91%), hemoperitoneum in 6 patients (55%), intestinal bleeding in 3 patients (27%), and occasionally perihepatic hematomas or signs of active bleeding.

CONCLUSION

Although a rare entity, hemorrhagic cholecystitis may be present, and management can be delayed if the appropriate imaging modality is not used for diagnosis.

Imaging of acute abdomen in cancer patients

The pattern of disease causing acute abdominal pain has changed over last few decades, some of this has been attributed to intraabdominal cancers. The most common acute abdominal complaints in cancer patients are related to the gastrointestinal system. Abdominal emergencies in cancer patients can result from the underlying malignancy itself, cancer therapy and/or result from the standard pathologies causing acute abdomen in otherwise healthy population. Therapy-related or disease-related immunosuppression or high dose analgesics often blunt many of the findings which are usually expected in non-cancer general population. This complicates the clinical picture rendering the clinical exam less reliable in many cancer patients, and resulting in different pathologies which clinicians and the radiologists should remain aware of. This article focuses on imaging illustrations with differential diagnosis for various emergency scenarios related to acute abdomen specifically in oncologic settings.

Gallstones top to toe: what the radiologist needs to know

Gallstone-related disease can have significant associated morbidity and mortality worldwide. The incidence of gallstone-related disease in the Western world is on the increase. There are multiple different pathological manifestations of gallstone disease: the presentation, diagnosis and associated complications of which vary significantly depending on anatomical location. The role of imaging in gallstone-related disease is broad with radiology playing an essential role in the diagnosis, management and follow-up of gallstone-related pathologies. This paper distills the broad range of gallstone-related pathologies into an anatomical map, discussing the disease processes involved at each point along the biliary tree and reviewing the strengths and weaknesses of different imaging modalities for each distinct disease process.

Imaging of Acute Hepatobiliary Dysfunction

Abdominal pain is a common cause for emergency department visits in the United States, and biliary tract disease is the fifth most common cause of hospital admission. Common causes of acute hepatobiliary include gallstones and its associated complications and multiple other hepatobiliary etiologies, including infectious, inflammatory, vascular, and neoplastic causes. Postoperative complications of the biliary tract can result in an acute abdomen. Imaging of the hepatobiliary tree is integral in the diagnostic evaluation of acute hepatobiliary dysfunction, and imaging of the biliary tree requires a multimodality approach utilizing ultrasound, computed tomography, nuclear medicine, and MR imaging.

A rare case of idiopathic cholestasis: Clinical conundrums complicating enzalutamide therapy in metastatic prostate cancer

Current safety data affirms enzalutamide does not cause clinically significant liver dysfunction that warrant therapy cessation. Therefore, clinicians should not withhold potentially successful therapy merely for suspected hepatotoxicity or PnC.

Hounsfield unit density in the characterisation of bile duct lesions

Purpose

To study the density of lesions in the lumens of extrahepatic bile ducts through computed tomography examinations, and to compare their characterisations with the results of pathology and/or endoscopic retrograde cholangiopancreatography (ERCP).

Methods

The density of lesions along extrahepatic bile ducts were measured and compared with pathology and/or ERCP. The lesions were evaluated in two main groups: benign or malignant. The bile duct wall enhancement, intrahepatic bile ducts, and gallbladder were also evaluated.

Results

The study was conducted with computed tomography scans of 197 cases (93 females, 104 males) who had optimal imaging. The results regarding density of extrahepatic intraductal lesions that were studied at BT were compared with pathology and magnetic resonance cholangiopancreatography results. Of 197 lesions, 125 (63.5%) were reported as benign and 72 (36.5%) were reported as malignant. The results for benign lesions showed an average density of 66.67 ± 17.30 Hounsfield units (HU), and for malignant lesions the average density was 82.38 ± 13.67 HU.

Conclusion

Lesion density level (HU) gives valuable information for the differentiation between benign and malign lesions in intraluminal extrahepatic bile ducts.

[Differential diagnoses of biliary tract diseases : Computed tomography and magnetic resonance imaging]

CLINICAL/METHODICAL ISSUE

Bile duct diseases can be found in all age groups and show an increased prevalence in northern Europe. Pathologies range from benign diseases to malignant tumors with very poor survival.

STANDARD RADIOLOGICAL METHODS

Magnetic resonance imaging (MRI) and computed tomography (CT) are the radiological methods of choice for a detailed evaluation of the bile duct system in addition to sonography. By assessing the lumen and the wall of the bile ducts as well as the surrounding structures, both obstructive and nonobstructive pathologies can be diagnosed and differentiated with high sensitivity and specificity.

METHODICAL INNOVATIONS

Technical developments with postprocessing modalities as well as the use of biliary-excreted liver-specific MR contrast agents improve the diagnosis of bile duct diseases and enable morphological and functional assessment.

PERFORMANCE

Due to high patient tolerance, minimal procedural risk in contrast to invasive endoscopic methods and the possibility of three-dimensional post-processing, beside CT, MRI with magnetic resonance cholangiography (MRC) represents the method of choice in patients with sonographically or clinically suspected bile duct disease and has significantly reduced the indications of diagnostic endoscopic retrograde cholangiopancreatography (ERCP). A complementary multimodality and multiparametric imaging approach is particularly helpful for preoperative assessment.

PRACTICAL RECOMMENDATIONS

Rapidly evolving technology for both MRI and CT represent opportunities and challenges. By understanding the advantages and limitations of modern MR and CT techniques and by knowing the spectrum of bile duct pathologies, improved diagnosis and narrowing of possible differential diagnosis can be achieved.

Hepatic computed tomography and cholangiography by use of gadoxetic acid in healthy cats

OBJECTIVE

To evaluate 3 doses of gadoxetic acid (Gd-EOB-DPTA) for hepatic CT and cholangiography in cats and to determine optimal timing for hepatobiliary image acquisition and evaluation of the contrast-enhanced hepatobiliary anatomy.

ANIMALS

6 healthy cats.

PROCEDURES

Cats were anesthetized; sequential CT scans were performed 0, 5, 25, 45, 65, and 85 minutes after IV administration of Gd-EOB-DTPA at low (0.0125 mmol/kg), medium (0.1 mmol/kg), and high (0.3 mmol/kg) doses. Hepatobiliary enhancement for each dose was objectively assessed over time and by use of a subjective semiquantitative visual assessment score.

RESULTS

No contrast-related adverse effects were detected. Each increase in dose of contrast medium resulted in a significant increase in HU across the hepatobiliary system. The liver had a significantly higher number of HU at 45 minutes, with homogenous enhancement at all doses of contrast medium. Contrast-enhanced cystic and bile duct HU were significantly higher and maximal at 65 minutes. Contrast-enhanced gallbladder HU did not plateau by 85 minutes. At a high dose of contrast medium, 12 of 60 (20%) biliary tract scores indicated no enhancement, 34 (57%) indicated poor enhancement, and 14 (23%) indicated moderate enhancement. No cat had excellent enhancement of the biliary tract at any dose.

CONCLUSIONS AND CLINICAL RELEVANCE

Gd-EOB-DTPA-enhanced hepatic CT and cholangiography in cats were safely performed and provided good hepatic enhancement but poor to moderate enhancement of the biliary tract. This technique may be useful for assessing the liver parenchyma in cats, but its value for assessing the biliary tract is questionable.

The hepatoduodenal ligament revisited: cross-sectional imaging spectrum of non-neoplastic conditions

INTRODUCTION

The hepatoduodenal ligament is frequently involved by conditions affecting the portal triad and surrounding structures, including a vast array of non-neoplastic conditions. Due its unique location between the retroperitoneum and the peritoneal space, the hepatoduodenal ligament is also targeted by inflammatory conditions involving the retroperitoneum and the liver. Finally, the presence of lymphatics and of the biliary tracts makes the hepatoduodenal ligament a route of spread for a variety of infections. The purpose of this pictorial essay is twofold: to review the cross-sectional radiological anatomy and variants of the structures within the hepatoduodenal ligament, and to illustrate the non-neoplastic conditions that may arise within the hepatoduodenal ligament.

CONCLUSION

Familiarity with these specific entities and their cross-sectional imaging findings is fundamental for a more accurate diagnosis.

Radiologist and Sonographer Interpretation Discrepancies for Biliary Sonographic Findings: Our Experience

PURPOSE

The aim was to determine the discrepancy rate between the preliminary interpretation by sonographers and the final radiology interpretation for biliary sonographic findings.

MATERIALS AND METHODS

Institutional review board approval was obtained. Four hundred consecutive right upper quadrant sonographer performed ultrasounds were reviewed retrospectively. Sonographers' worksheets were compared with the final radiology report. For the purposes of this project, only the biliary findings were compared and reviewed. Discrepant findings were reviewed by 5 ultrasound experts, and a majority vote sought to determine truth, sonographer worksheet findings, or radiologist report. The clinical impact of the discrepant findings was also evaluated.

RESULTS

Of the 400 scans, there were 338 agreements and 62 discrepancies. The overall discrepancy rate was 15.5%. The most frequently contested discrepancy was the presence or absence of pericholecystic fluid n = 21. Sonographers (S) were deemed correct 8 times and radiologists (R) 13 times, denoted 8/13 (S/R). The overall split was 30/32 (S/R) with radiologists deemed correct 52% of the time and sonographers 48% of the time. Using a 1-sample proportion χ test with Yates' continuity correction, there were no statistically significant discrepancies between the 2 groups.

CONCLUSIONS

We observed an interpretation discrepancy rate of 15.5% with radiologists deemed correct slightly more frequently, although this did not meet statistical significance. Clinically impactful discrepant findings (6.5% of all discrepancies) were all correctly called by the radiologists. Both groups bring tremendous value to the ultrasound arena, and continued collaboration should be encouraged.

PURPOSE

The aim of this study was to determine the discrepancy rate that exists between the preliminary interpretation by sonographers and the subsequent final radiology interpretation for biliary sonographic findings.

Fingerprinting Acute Digestive Diseases by Untargeted NMR Based Metabolomics

Precision medicine may significantly contribute to rapid disease diagnosis and targeted therapy, but relies on the availability of detailed, subject specific, clinical information. Proton nuclear magnetic resonance (¹H–NMR) spectroscopy of body fluids can extract individual metabolic fingerprints. Herein, we studied 64 patients admitted to the Florence main hospital emergency room with severe abdominal pain. A blood sample was drawn from each patient at admission, and the corresponding sera underwent ¹H–NMR metabolomics fingerprinting. Unsupervised Principal Component Analysis (PCA) analysis showed a significant discrimination between a group of patients with symptoms of upper abdominal pain and a second group consisting of patients with diffuse abdominal/intestinal pain. Prompted by this observation, supervised statistical analysis (Orthogonal Partial Least Squares–Discriminant Analysis (OPLS-DA)) showed a very good discrimination (>90%) between the two groups of symptoms. This is a surprising finding, given that neither of the two symptoms points directly to a specific disease among those studied here. Actually herein, upper abdominal pain may result from either symptomatic gallstones, cholecystitis, or pancreatitis, while diffuse abdominal/intestinal pain may result from either intestinal ischemia, strangulated obstruction, or mechanical obstruction. Although limited by the small number of samples from each of these six conditions, discrimination of these diseases was attempted. In the first symptom group, >70% discrimination accuracy was obtained among symptomatic gallstones, pancreatitis, and cholecystitis, while for the second symptom group >85% classification accuracy was obtained for intestinal ischemia, strangulated obstruction, and mechanical obstruction. No single metabolite stands up as a possible biomarker for any of these diseases, while the contribution of the whole ¹H–NMR serum fingerprint seems to be a promising candidate, to be confirmed on larger cohorts, as a first-line discriminator for these diseases.

Acute Biliary Disease

Acute biliary disease is a ubiquitous acute surgical complaint. General surgeons managing emergency surgical patients must be knowledgeable and capable of identifying and caring for common presentations. This article discusses the work-up, diagnosis, and management of the varying pathologies that make up biliary disease including cholelithiasis, cholecystitis, biliary dyskinesia, choledocholithiasis, cholangitis, gallstone pancreatitis, and gallstone ileus. Also addressed are more challenging and rare presentations including pregnancy and bariatric anatomy.

Elevated Levels of Urinary 8-oxodG Correlate with Persistent Periductal Fibrosis after Praziquantel Treatment in Chronic Opisthorchiasis

Previous studies demonstrated that urinary 8-oxodG is a predictive biomarker for Opisthorchis viverrini (OV)-associated hepatobiliary disease (HBD) and cholangiocarcinoma (CCA). This study examined the effects of praziquantel treatment on the profile of urinary 8-oxodG in relation to HBD status. Infection with OV, levels of urinary 8-oxodG, and HBD status in terms of periductal fibrosis (PDF) assessed by abdominal ultrasonography (US) were monitored and compared in cohorts of participants in Khon Kaen, Thailand, before and 1 year after praziquantel treatment. Urinary 8-oxodG levels significantly decreased after treatment compared with the baseline level in OV-infected participants who had no HBD (PDF negative; PDF-ve) (N = 14). Levels of 8-oxodG were unchanged after treatment in OV-infected subjects (OV+ve) who had positive PDF (N = 52). Within the positive PDF (PDF+ve) group who became PDF-ve after treatment, there was no significant change in 8-oxodG levels between pre-and posttreatment (reversible PDF = 65.3%). In those who had persistent PDF+ve at both ultrasound sampling points, there was no significant difference in urinary 8-oxodG levels between pre- and posttreatment (persistent PDF = 34.6%). Based on a logistic regression model and receiver operation curve analysis, the increase of 8-oxodG levels was found to be associated with increasing risk of PDF. Measurement of urinary 8-oxodG and US increased the likelihood of discovering persistent PDF, which is a predictable condition for the patients at risk of OV-associated CCA. To identify high-risk individuals for CCA, it is useful to perform US in combination with urinary 8-oxodG measurement.

Teleconsultation ultrasonography: a new weapon to combat cholangiocarcinoma

Although cholangiocarcinoma (CCA) is usually a rare cancer, in northeast Thailand it kills 20 000 or more people every year. The prognosis is very poor owing to late stage diagnosis, with palliative treatment often representing the only option. In this area of predominantly rural Thailand, CCA is associated with infection with the liver fluke, Opisthorchis viverrini, which is classified as a group 1 carcinogen. Up to 6 million Thais are infected with this fluke. The Cholangiocarcinoma Screening and Care Program (CASCAP) was initiated in 2014 with the aim of detecting early stage CCA, allowing curative surgery, by using ultrasound (US) screening of prospectively 500 000 at risk individuals. In order to assess the massive number of radiological images, a teleconsultation system was set-up. This allows US images to be sent to a dedicated server where they can be viewed by an expert radiologist who then provides a provisional diagnosis, recommending more advanced diagnostic techniques (CT and MRI) for suspected cases. To date, 250 000 people have been screened, and 2000 cases of CCA diagnosed. This innovative information transfer procedure will also be made available to Laos, Cambodia and Vietnam, where O. viverrini infection is also common.

Adequacy of ultrasound reports in patients presenting with obstructive jaundice at a tertiary hospital radiology department

Background: Patients with obstructive jaundice require a stepwise approach to investigation and management. Ultrasound (US) is the initial screening modality of choice and has been shown to be accurate in demonstrating the presence of dilated bile ducts, as well as the level and cause of obstruction. For adequate radiological communication to the clinician, degree of bile duct dilatation, level of obstruction, appearance of the transition zone and cause of obstruction must be reported. However, without a structured reporting method, much of this information may be omitted.Objectives: The aim of the study was to investigate the adequacy of US findings in patients with obstructive jaundice, as documented, without standardised reporting.Methods: A retrospective chart review of 130 US reports of adult patients presenting at Grey’s Hospital US Department with a clinical assessment of obstructive jaundice was conducted. Data for the period January to December 2013, were analysed. US reports of patients with dilated bile ducts were assessed for report adequacy by looking at four important clinical factors, that is, the degree of bile duct dilatation, the level of obstruction, the appearance of the transition zone and the cause of the obstruction.Results: A report adequacy score was assessed in 79 patients with dilated bile ducts; however, two reports were excluded because of obscuration by gas. There was a high level of report inadequacy (38%) without the use of a structured reporting template. The level of obstruction was the most common component missing from the reports (25%), followed by the appearance of the transition zone (18%) and cause of obstruction (12%).Conclusion: We propose the use of an US report template for obstructive jaundice patients in order to ensure comprehensive reporting. Structured radiological reporting will improve the method of communication between clinicians and radiologists, thus improving the quality of patient care.

Biliary strictures and masses: an expanded differential diagnosis

Biliary strictures and masses are commonly a result of cholangiocarcinoma. However, there are several congenital, infectious, inflammatory, autoimmune, iatrogenic, and neoplastic etiologies that should also be considered in the differential diagnosis. Knowledge of the key imaging and clinical findings will aid in facilitating the diagnosis and treatment.

MR cholangiopancreatography of the pancreas and biliary system: a review of the current applications

MR cholangiopancreatography (MRCP) is still a rapidly evolving technique, but it has been already accepted as clinically useful and is widely used to evaluate biliary or pancreatic diseases. The advantages of this technique are that it does not use contrast media or ionizing radiation, it is noninvasive and complication free, and the examination is relatively short. MRCP has high sensitivity and specificity for diagnosing biliary dilatation and for determining the site and cause of stenosis. With further improvements of hardware and technique, MRCP is expected to replace diagnostic endoscopic retrograde cholangiopancreatography to examine the biliary and pancreatic ducts in the near future. The other applications include evaluation of primary sclerosing cholangitis, stenosis after liver transplantation, and bilioenteric anastomoses. This article reviews the current applications of MRCP in the evaluation of the pancreas and the biliary system.

Feasibility of endoscopic retrograde cholangiopancreatography in healthy cats

Cats are predisposed to diseases of the biliary tract and the exocrine pancreas and these can be challenging to diagnose. In humans and dogs > 10 kg, endoscopic retrograde cholangiopancreatography (ERCP) has been successfully used to diagnose some of these disorders. The purpose of our study was to determine whether ERCP would also be feasible in cats using a pediatric duodenoscope. Four purpose-bred, clinically healthy, castrated domestic shorthair cats participated in two studies. Study 1 compared standard white light endoscopy with chromoendoscopy for localizing the major duodenal papilla. In Study 2 ERCP was performed. Repeated clinical examinations and measurements of serum feline pancreatic lipase immunoreactivity (fPLI) were performed before and up to 18 hours after interventions on all cats. Chromoendoscopy was subjectively judged to be superior for localizing the major papilla. Insertion of the ERCP catheter was best accomplished when cats were in dorsal recumbency. Complete ERCP was successful in two cats. In the other cats, either retrograde cholangiography or pancreatography was possible. Serum fPLI concentrations increased temporarily in two cats during Study 2 when measured immediately, 2, 4, and 18 h after ERCP. Peak fPLI concentrations were detected either immediately after ERCP or 2 h later. No clinical signs of complications were observed within 18 h after the procedures. Findings indicated that ERCP is technically demanding but feasible in healthy cats. Future studies need to determine whether the temporary increases in serum fPLI concentrations are clinically important and to investigate the utility of ERCP in feline patients.

MDCT of abdominopelvic oncologic emergencies

Acute complications arising in abdominopelvic malignancies represent a unique subset of patients presenting to the emergency room. The acute presentation can be due to complications occurring in the tumor itself or visceral or vascular structures harboring the tumor. Multidetector computed tomography (MDCT) is the investigation of choice in the workup of these patients and enables appropriate and timely management. Management of the complication depends primarily on the extent of the underlying malignancy and the involvement of other viscera. The purpose of this article is to depict the imaging features of these complications on MDCT.

Visualization of bile movement using MRI spin-labeling technique: preliminary results

OBJECTIVE

The purpose of this article is to noninvasively visualize intrabiliary bile movement using an MRI spin-labeling technique and administration of water, full-fat milk, and negative contrast agent as stimuli for bile excretion.

SUBJECTS AND METHODS

Six healthy volunteers underwent three studies with each of three oral liquid agents (water, full-fat milk, and manganese chloride solution) for a total of 18 MRI studies. Oblique-coronal T2-weighted images of the common bile duct were acquired at an inversion time of 1500 milliseconds after pulse labeling using a spin-labeling technique with an inversion pulse, repeated at intervals of 22 seconds. Bile flow rate was measured before and for 50 minutes after administration of the oral liquid agents, and its correlation with the change in gallbladder volume was assessed.

RESULTS

Both anterograde and retrograde intermittent bile movements were successfully visualized in the common bile duct. The summation of excreted bile volume calculated from spin-labeled images correlated significantly with a decrease in gallbladder volume (p = 0.011). Milk stimulated significantly prolonged bile flow; flow was momentary with manganese chloride and mild with water; however, gallbladder volume decreased only in milk studies (p = 0.003). Biliary flow early after oral intake correlated significantly with gallbladder contractility at 50 minutes after oral intake (p = 0.049).

CONCLUSION

A new method for visualizing intrabiliary bile movement in semi-real time (22-second time resolution) using an MRI spin-labeling technique was proposed. Bile was shown to be excreted in a to-and-fro type of movement. Administration of water and negative contrast agent may induce temporary bile excretion.

Early phase detection of bile leak after hepatobiliary surgery: value of Gd-EOB-DTPA-enhanced MR cholangiography

PURPOSE

To assess the value of gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid (Gd-EOB-DTPA)-enhanced MR cholangiography for the detection of bile leaks after hepatobiliary surgery.

METHODS

Twenty-three patients with symptoms suggestive of bile leak underwent conventional fat-suppressed T1- and T2-weighted MR cholangiography followed by Gd-EOB-DTPA-enhanced MR cholangiography using gradient-echo (GRE) T2-weighted sequences and fat-suppressed T1-weighted 3D gradient-echo sequences 20 min after an intravenous bolus of Gd-EOB-DTPA. The results of Gd-EOB-DTPA-enhanced MR cholangiography correlated with clinical findings, surgical repair, and the results of endoscopic retrograde cholangiopancreatography and percutaneous transhepatic cholangiography.

RESULTS

The results of Gd-EOB-DTPA-enhanced MR cholangiography were negative in 13 patients (cholecystectomy 5, liver transplantation 2, liver resection for focal lesions 2, cholangiocarcinoma 1, and partial hepatectomy after liver injury 1). In 10 patients in whom bile leaks were detected, this complication occurred after liver resection for focal lesions in 3, cholecystectomy in 4, liver transplantation in 2, and liver resection for intrahepatic cholangiocarcinoma in 1. The diagnostic accuracy of Gd-EOB-DTPA-enhanced MR for the detection or exclusion of bile leaks was 100%.

CONCLUSIONS

Gd-EOB-DTPA-enhanced MR cholangiography is a highly reliable technique for the detection of bile leaks after hepatobiliary surgery and may avoid the use of other, potentially risky invasive diagnostic techniques.