Is magnetic resonance cholangiopancreatography the new gold standard in biliary imaging?

Magnetic resonance cholangiopancreatography using T2 preparation pulse: quantitative and qualitative analyses

BACKGROUND

Magnetic resonance cholangiopancreatography (MRCP) may exhibit ghosting and blurring artifacts due to irregular breathing cycles, which can be overcome by shortening the shot duration. T2 preparation pulse enables heavy T2 contrast even with a shorter TE by use of the shortened shot duration; therefore, a technique using T2 preparation pulse combined with 3D turbo spin-echo MRCP (TPT-MRCP) was constructed.

PURPOSE

To evaluate the clinical usefulness of TPT-MRCP in both navigation and breath-hold sequences compared to the conventional method.

MATERIAL AND METHODS

We obtained navigation MRCP, which were TPT and conventional 3D turbo spin-echo in 37 patients, and breath-hold MRCP in 31 patients, which were TPT and gradient and spin echo. The quantitative evaluation included signal-to-noise ratio, contrast ratio, contrast-to-noise ratio and sharpness of the common bile duct in all sequences. Two radiologists visually evaluated image quality using a five-point grading method, assessing overall image quality and each of the six areas: common bile duct, right hepatic duct, left hepatic duct, main pancreatic duct, cystic duct and motion artifact.

RESULTS

TPT-MRCP was significantly superior to conventional MRCP in all quantitative evaluations, except for signal-to-noise ratio in the navigation sequence. In the visual evaluation, TPT-MRCP provided higher image quality than the conventional technique in nearly all areas. The kappa (k) coefficient of the overall image quality was good for all sequences (κ = 0.61-0.8).

CONCLUSION

TPT-MRCP provides higher image quality than conventional techniques in both navigation and breath-hold sequences. The present study demonstrates the greater clinical usefulness of TPT-MRCP.

Evaluation of the Common bile duct (CBD) Diameter After Laparoscopic Cholecystectomy (LC) and Laparoscopic Common Bile Duct Exploration (LCBDE): A Retrospective Study

BACKGROUND

Common Bile duct (CBD) measurement is a crucial aspect in the evaluation of the biliary tree. Whether the CBD undergoes any compensatory change in diameter after laparoscopic cholecystectomy or laparoscopic common bile duct exploration is still up for discussion. The aim of this study was to investigate CBD diameter changes after laparoscopic cholecystectomy (LC) and laparoscopic common bile duct exploration (LCBDE) on magnetic resonance cholangiopancreatography (MRCP).

MATERIALS AND METHODS

Our retrospective study is divided into 2 sections. The first part assessing CBD diameter changes after laparoscopic cholecystectomy due to gallstones or gallbladder polyps, involved 85 patients, who underwent MRCP procedures. These patients aged between 30 and 85 were divided into an interval LC group (group A, n=56) and a remote LC group (group B, n=29). In group A, the common CBD diameters were measured at their widest portions on MRCP obtained before and after laparoscopic cholecystectomy. Measurements of the CBD diameters were repeated on MRCP obtained twice after the surgery in group B.Section 2 consisted of 38 patients who had choledocholithiasis and were treated with laparoscopic CBD exploration and T-tube placement. These patients aged 26 to 86 formed the interval LCBDE group (group C). The CBD widest diameters were measured on MRCP before LCBDE and after T-tube cholangiography for these individuals.Patients in groups A and C were further divided into 5 and those in group B into 4 age-related subgroups to facilitate statistical analysis. The Pearson correlation test was performed to find any relationship between CBD diameters and age in groups A and B. Paired sample T test was used to compare the significant difference between the 2 sets of CBD diameters in each study group and their subgroups.

RESULTS

In the interval LC group, the post-LC mean CBD diameter was significantly wider when compared with the preoperative mean diameter ( P <0.05). There was a significant difference between the first and second post-LC means CBD diameter in the remote LC group ( P <0.05). In group C, the mean CBD diameter measured on T-tube cholangiography after LCBDE was significantly smaller than the preoperative dilated mean diameter ( P <0.05).

CONCLUSIONS

This study demonstrated significant dilation occurring in the common bile duct diameter after laparoscopic cholecystectomy. Furthermore, our remote LC group also supported that claim by showing significant dilation between the first and second post-cholecystectomy CBD diameter values. And lastly, our interval LCBDE sample's initial dilation of the CBD diameters was reduced after surgery and stone extraction.

Incidental Findings of Gallbladder and Bile Ducts-Management Strategies: General Aspects, Gallbladder Polyps and Gallbladder Wall Thickening-A World Federation of Ultrasound in Medicine and Biology (WFUMB) Position Paper

The World Federation of Ultrasound in Medicine and Biology (WFUMB) is addressing the issue of incidental findings with a series of position papers to give advice on characterization and management. The biliary system (gallbladder and biliary tree) is the third most frequent site for incidental findings. This first part of the position paper on incidental findings of the biliary system is related to general aspects, gallbladder polyps and other incidental findings of the gallbladder wall. Available evidence on prevalence, diagnostic work-up, malignancy risk, follow-up and treatment is summarized with a special focus on ultrasound techniques. Multiparametric ultrasound features of gallbladder polyps and other incidentally detected gallbladder wall pathologies are described, and their inclusion in assessment of malignancy risk and decision- making on further management is suggested.

Percutaneous Biliary Interventions: Clinical Indications, Comparative Effectiveness, Technical Considerations, Complications, and Outcomes

Percutaneous biliary interventions (PBIs) are commonly performed by interventional radiologists for a variety of clinical indications including biliary infections, strictures, leaks, and postoperative complications. PBIs have high technical and clinical success rates and are relatively safe when compared with more invasive surgical techniques. Percutaneous transhepatic cholangiography and percutaneous biliary drainage play an essential role in the management of common posthepatobiliary complications including biliary strictures and leaks. Percutaneous biliary endoscopy can be used for direct visualization of the biliary tree and a variety of interventions including tissue biopsy, lithotripsy, stone removal, as well as stent placement and removal.

Ultrasonographic evaluation of patients with abnormal liver function tests in the emergency department

Ultrasonography is often the initial modality used to evaluate patients found to have abnormal liver function tests (LFTs) in the emergency department. While an assessment for biliary ductal dilatation and obstruction remains one of the main questions to answer, radiologists should also be aware of the ultrasonographic appearance of other conditions that can cause abnormal LFTs. This may be crucial for the management and disposition of patients in the emergency department. This article reviews the ultrasonographic features of diseases that may cause abnormal LFTs.

A Single Centre Experience With Routine Magnetic Resonance Cholangiopancreatography in the Management of Patients With Gall Stone Disease

AIM

To evaluate the role of preoperative magnetic resonance cholangiopancreatography (MRCP) in detection of common bile duct stone (CBDS) in cases of gall stone disease (GSD).

METHODS

This is a retrospective study with a prospectively maintained database, carried out in 116 patients who underwent laparoscopic cholecystectomy (LC) for GSD, from October 2017 to September 2020. Preoperative MRCP was performed in all cases.

RESULTS

MRCP detected CBDS in 23 out of 116 patients (19.8%) including silent CBDS in seven patients (6%). In situations of normal biochemical parameters and USG abdomen, 30.4% unnoticed CBDS out of all 23 CBDS, were discovered by MRCP. The sensitivity and specificity of aspartate aminotransferase (AST) or alanine aminotransferase (ALT) [positive predictive value (PPV): 24%; negative predictive value (NPV): 81.3%], alkaline phosphatase (ALP) (PPV: 63.2%; NPV: 88.7%), serum total bilirubin (PPV: 57.1%; NPV: 88.4%) and CBD diameter (PPV: 61.5%; NPV: 85.4%) were, respectively, 26.1% and 79.6%, 52.2% and 92.5%, 52.2% and 90.3%, and 34.8% and 94.6%. Cystic duct variations found in nine patients (7.75%). There was no bile duct injury (0%) noted in post operative patients.

CONCLUSION

With normal biochemical and USG parameters, MRCP is a valuable non-invasive investigation to detect the overlooked CBDS. After recognising the cystic duct variants, it may be possible to prevent bile duct injury. Before performing a laparoscopic cholecystectomy (LC) in GSD, a routine preoperative MRCP is highly recommended.

Fluorescent cholangiography: An up-to-date overview twelve years after the first clinical application

Laparoscopic cholecystectomy (LC) is one of the most frequently performed gastrointestinal surgeries worldwide. Bile duct injury (BDI) represents the most serious complication of LC, with an incidence of 0.3%-0.7%, resulting in significant perioperative morbidity and mortality, impaired quality of life, and high rates of subsequent medico-legal litigation. In most cases, the primary cause of BDI is the misinterpretation of biliary anatomy, leading to unexpected biliary lesions. Near-infrared fluorescent cholangiography is widely spreading in clinical practice to delineate biliary anatomy during LC in elective and emergency settings. The primary aim of this article was to perform an up-to-date overview of the evolution of this method 12 years after the first clinical application in 2009 and to highlight all advantages and current limitations according to the available scientific evidence.

Safety of endoscopic retrograde cholangiopancreatography in the pediatric population: a multicenter study

INTRODUCTION

The aims of this retrospective multicenter study were to assess the technical success and adverse events of endoscopic retrograde cholangiopancreatography (ERCP) procedures in children in French and Belgian centers.

METHODS

All children aged 1 day to 17 years who underwent ERCP between January 2008 and March 2019 in 15 tertiary care hospitals were retrospectively included.

RESULTS

271 children underwent 470 ERCP procedures. Clinical long-term follow-up was available for 72 % of our patients (340/470 procedures). The median age at intervention was 10.9 years. ERCP was therapeutic in 90 % (423/470) and diagnostic in cases of neonatal cholestasis in 10 % of the patients. The most common biliary indication was choledocholithiasis; the most common pancreatic indication was chronic pancreatitis. Biliary cannulation was successful in 92 % of cases (270/294); pancreatic cannulation in 96 % of cases (169/176); and planned therapeutic procedures in 92 % of cases (388/423). The overall complication rate was 19 % (65/340). The most common complication was post-ERCP pancreatitis (PEP) in 12 % of cases (40/340) and sepsis in 5 % (18/340). On univariate analyses, pancreatic stent removal was protective against PEP (odds ratio [OR] 0.1, 95 % confidence interval [CI] 0.01 - 0.75; P = 0.03), and sepsis was associated with history of liver transplantation (OR 7.27, 95 %CI 1.7 - 31.05; P = 0.01). Five patients had post-ERCP hemorrhage and two had intestinal perforation. All complications were managed with supportive medical care. There was no procedure-related mortality.

CONCLUSION

Our cohort demonstrates that ERCP can be performed safely with high success rates in many pancreaticobiliary diseases of children. The rate of adverse events was similar to that in previous reports.

Comparison of Compressed Sensing and Gradient and Spin-Echo in Breath-Hold 3D MR Cholangiopancreatography: Qualitative and Quantitative Analysis

While magnetic resonance cholangiopancreatography (MRCP) is routinely used, compressed sensing MRCP (CS-MRCP) and gradient and spin-echo MRCP (GRASE-MRCP) with breath-holding (BH) may allow sufficient image quality with shorter acquisition times. This study qualitatively and quantitatively compared BH-CS-MRCP and BH-GRASE-MRCP and evaluated their clinical effectiveness. Data from 59 consecutive patients who underwent both BH-CS-MRCP and BH-GRASE-MRCP were qualitatively analyzed using a five-point Likert-type scale. The signal-to-noise ratio (SNR) of the common bile duct (CBD), contrast-to-noise ratio (CNR) of the CBD and liver, and contrast ratio between periductal tissue and the CBD were measured. Paired t-test, Wilcoxon signed-rank test, and McNemar’s test were used for statistical analysis. No significant differences were found in overall image quality or duct visualization of the CBD, right and left 1st level intrahepatic duct (IHD), cystic duct, and proximal pancreatic duct (PD). BH-CS-MRCP demonstrated higher background suppression and better visualization of right (p = 0.004) and left 2nd level IHD (p < 0.001), mid PD (p = 0.003), and distal PD (p = 0.041). Image quality degradation was less with BH-GRASE-MRCP than BH-CS-MRCP (p = 0.025). Of 24 patients with communication between a cyst and the PD, 21 (87.5%) and 15 patients (62.5%) demonstrated such communication on BH-CS-MRCP and BH-GRASE-MRCP, respectively. SNR, contrast ratio, and CNR of BH-CS-MRCP were higher than BH-GRASE-MRCP (p < 0.001). Both BH-CS-MRCP and BH-GRASE-MRCP are useful imaging methods with sufficient image quality. Each method has advantages, such as better visualization of small ducts with BH-CS-MRCP and greater time saving with BH-GRASE-MRCP. These differences allow diverse choices for visualization of the pancreaticobiliary tree in clinical practice.

The Overall Poor Specificity of MRCP in the Preoperative Evaluation of the Jaundiced Patient Will Increase the Incidence of Nontherapeutic ERCP

Laparoscopic cholecystectomy remains one of the most common surgical operations. Common bile duct stones (CBDS) are estimated to be present in 10%-20% of individuals with symptomatic gallstones. Preoperative magnetic resonance cholangiopancreatography (MRCP) and intraoperative cholangiography (IOC) remain the most common methods of evaluation, with subsequent endoscopic retrograde cholangiopancreatography (ERCP) for stone extraction if positive for CBDS. We examined our experience with preoperative MRCP versus IOC for the management of the jaundiced patient with cholelithiasis. This is a retrospective single-institution study that examined all laparoscopic cholecystectomies performed over a 15-month period between 2017 and 2018. Outpatient elective cases were excluded from the analysis. Charts were reviewed for demographics, operative details, and whether an MRCP, IOC, or ERCP was performed. Data were evaluated using a 2-sample t-test. A total of 460 patients underwent laparoscopic cholecystectomy over a 15-month period. Of those, 147 underwent either an MRCP or an IOC for clinical suspicion for CBDS. ERCP after MRCP was nontherapeutic in 11/32 (34%) compared with 2/12 (17%) of patients following IOC. The sensitivity and specificity of MRCP were 91% and 80%, respectively, with a positive predictive value of 66% and a negative predictive value of 96%. The sensitivity and specificity of IOC were 83% and 97%, respectively, with a positive predictive value of 83% and a negative predictive value of 97%. MRCP and IOC have unique advantages and disadvantages. MRCP has greater sensitivity, but poor specificity, resulting in unnecessary ERCPs with associated morbidity and increased costs to the patient.

Optimized Breath-Hold Compressed-Sensing 3D MR Cholangiopancreatography at 3T: Image Quality Analysis and Clinical Feasibility Assessment

Magnetic resonance cholangiopancreatography (MRCP) has been widely used in clinical practice, and recently developed compressed-sensing accelerated MRCP (CS-MRCP) has shown great potential in shortening the acquisition time. The purpose of this prospective study was to evaluate the clinical feasibility and image quality of optimized breath-hold CS-MRCP (BH-CS-MRCP) and conventional navigator-triggered MRCP. Data from 124 consecutive patients with suspected pancreaticobiliary diseases were analyzed by two radiologists using a five-point Likert-type scale. Communication between a cyst and the pancreatic duct (PD) was analyzed. Signal-to-noise ratio (SNR) of the common bile duct (CBD), contrast ratio between the CBD and periductal tissue, and contrast-to-noise ratio (CNR) of the CBD and liver were measured. Optimized BH-CS-MRCP showed significantly fewer artifacts with better background suppression and overall image quality. Optimized BH-CS-MRCP demonstrated communication between a cyst and the PD better than conventional MRCP (96.7% vs. 76.7%, p = 0.048). SNR, contrast ratio, and CNR were significantly higher with optimized BH-CS-MRCP (p < 0.001). Optimized BH-CS-MRCP showed comparable or even better image quality than conventional MRCP, with improved visualization of communication between a cyst and the PD.

Effectiveness of near-infrared fluorescent cholangiography in the identification of cystic duct-common hepatic duct anatomy in comparison to magnetic resonance cholangio-pancreatography: a preliminary study

INTRODUCTION

Bile duct injury represents the most serious complication of LC, with an incidence of 0.3-0.7% resulting in a significant impact on quality-of-life, overall survival, and frequent medico-legal litigations. Near-infrared fluorescent cholangiography (NIRF-C) represents a novel intra-operative imaging technique that allows a real-time enhanced visualization of the extrahepatic biliary tree by fluorescence. The role of routine use of pre-operative magnetic resonance cholangio-pancreatography (MRCP) to better clarify the biliary anatomy before laparoscopic cholecystectomy is still a matter of debate. The primary aim of this study was to evaluate the effectiveness of NIRF-C in the detection of cystic duct-common hepatic duct anatomy intra-operatively in comparison with pre-operative MRCP.

METHODS

Data from 26 consecutive patients with symptomatic cholelithiasis or chronic cholecystitis, who underwent elective laparoscopic cholecystectomy with intra-operative fluorescent cholangiography and pre-operative MRCP examination between January 2018 and May 2018, were analyzed. Three selected features of the cystic duct-common hepatic duct anatomy were identified and analyzed by the two different imaging methods: insertion of cystic duct, cystic duct-common hepatic duct junction, and cystic duct course.

RESULTS

Fluorescent cholangiography was performed successfully in all twenty-six patients undergoing elective laparoscopic cholecystectomy. The visualization of cystic duct was reported in 23 out of 26 cases, showing an overall diagnostic accuracy of 86.9%. The level of insertion, course, and wall implantation of cystic duct were achieved by NIRF-C with diagnostic accuracy values of 65.2%, 78.3%, and 91.3%, respectively in comparison with MRCP data. No bile duct injuries were reported.

CONCLUSION

Fluorescent cholangiography can be considered a useful imaging diagnostic tool comparable to MRCP for detailed intra-operative visualization of the cystic duct-common hepatic duct anatomy during elective laparoscopic cholecystectomies.

2019 WSES guidelines for the management of severe acute pancreatitis

Although most patients with acute pancreatitis have the mild form of the disease, about 20-30% develops a severe form, often associated with single or multiple organ dysfunction requiring intensive care. Identifying the severe form early is one of the major challenges in managing severe acute pancreatitis. Infection of the pancreatic and peripancreatic necrosis occurs in about 20-40% of patients with severe acute pancreatitis, and is associated with worsening organ dysfunctions. While most patients with sterile necrosis can be managed nonoperatively, patients with infected necrosis usually require an intervention that can be percutaneous, endoscopic, or open surgical. These guidelines present evidence-based international consensus statements on the management of severe acute pancreatitis from collaboration of a panel of experts meeting during the World Congress of Emergency Surgery in June 27-30, 2018 in Bertinoro, Italy. The main topics of these guidelines fall under the following topics: Diagnosis, Antibiotic treatment, Management in the Intensive Care Unit, Surgical and operative management, and Open abdomen.

The role of intraoperative cholangiography in patients undergoing laparoscopic cholecystectomy for acute gallstone pancreatitis: is magnetic resonance cholangiopancreatography needed?

INTRODUCTION

Intraoperative cholangiography is sporadically used in patients undergoing laparoscopic cholecystectomy to delineate common bile duct anatomy and exclude retained stones. In patients with acute gallstone pancreatitis, intraoperative cholangiography may reduce the need for preoperative magnetic resonance cholangiopancreatography.

MATERIALS AND METHODS

A retrospective review of a prospectively collected patient database was undertaken over a 15-year period. The primary objective was to evaluate intraoperative assessment of the common bile duct with intraoperative cholangiography in patients with acute gallstone pancreatitis.

RESULTS

A total of 2215 patients underwent laparoscopic cholecystectomy between October 1998 and December 2013; 113 patients (of whom 77 were women) with a mean age of 54 years (range 16-88 years) were diagnosed with acute gallstone pancreatitis. Of these, 102 patients (90%) underwent laparoscopic cholecystectomy with intraoperative cholangiography, which was normal in 89 cases. Thirteen patients had choledocholithiasis on intraoperative cholangiography, 11 of whom were managed with concomitant trans-cystic duct exploration and clearance. Two patients required postoperative endoscopic retrograde cholangiopancreatography.

CONCLUSIONS

In patients diagnosed with acute gallstone pancreatitis, it is reasonable to proceed directly to surgery using intraoperative cholangiography on the same admission as the definitive assessment of the common bile duct. This negates the need for magnetic resonance cholangiopancreatography and can translate into cost savings and reduced length of stay.

The use of imaging in acute pancreatitis in United Kingdom hospitals: findings from a national quality of care study

OBJECTIVE

To assess use of imaging in patients admitted to UK hospitals with acute pancreatitis (AP).

METHODS

4,479 patients had a diagnosis AP in the first 6 months of 2014. The National Confidential Enquiry into Patient Outcome and Death (NCEPOD) selected patients with more severe AP for case review. Clinicians completed 712 questionnaires and case reviewers assessed 418 cases. The use of imaging in patients with AP is reported.

RESULTS

The common causes of AP were gallstones (46.5%) and alcohol excess (22%) with no cause identified in 17.5%. Imaging was needed to diagnose AP in 12%. 60.1% of patients had one or more CT scan. The timing of the CT scan(s) was appropriate in 90% of patients. The number of CTs was appropriate in all except 6.6% (equally split between too many and too few). AP collection intervention was radiological in 49/613 and surgical in 23/613. 69.8% had an ultrasound scan which diagnosed gallstones in 46.4% and bile duct dilatation in 12.9%. At least 21% had ultrasound scan inappropriately omitted. The National Confidential Enquiry into Patient Outcome and Death recommends gallstones are excluded in all patients with AP, including suspected alcohol-related AP. 29.8% underwent magnetic resonance cholangio--pancreatography diagnosing gallstones in 62.4%, bile duct dilatation in 25.4% and common bile duct stones in 14.4%. 20.6% had recurrent pancreatitis with gallstones accounting for a third. 17% with gallstone AP had a cholecystectomy within the guideline recommended time period.

CONCLUSION

Imaging is rarely required for the diagnosis of AP. CT is used responsibly in AP management. Imaging should be used more to exclude gallstones, including in presumed alcohol related AP. Increased diagnostic efforts will not reduce recurrent biliary AP unless matched by earlier gallstone treatment. Advances in knowledge: Whilst CT is used responsibly in AP greater use of other diagnostic modalities is required to identify reversible causes, in particular gallstones, in order to prevent recurrent AP.

Unusual Use of Gd-EOB-DTPA in MRCP in Order to Reveal the Source of Bile Leakage in a Patient with Neuroendocrine Tumor - Case Report

BACKGROUND

MRCP is the method of choice in diagnosing pathologies of the biliary system. One of them is bile fistulae. They are uncommon but tend to cause many diagnostic problems. The possible way to improve MRCP is using it with intravenous injection of hepatobiliary-specific contrast agents. As it is eliminated via the hepatobiliary system, it can be visualized in the bile ducts and may help to reveal disorders undetected by a standard MRCP.

CASE REPORT

We report a case of a 36-year-old woman with leakage in the biliary system which led to creation of a subcutaneous bile reservoir. By means of a regular MRCP protocol it was impossible to reveal any disorders of the biliary system and thus a decision to inject Gd-EOB-DTPA was taken. As a result, a fistula with its opening in the fundus of the gall bladder was revealed. Patient was qualified for treatment with somatostatin analogues in order to stop bile secretion.

CONCLUSIONS

The Gd-EOB-DTPA in combination with regular T2-weighted MRCP may be helpful in detecting anomalies of the biliary system. Although a high price of the procedure restricts its accessibility, such advantages as lower risk of complications, lower costs of hospitalization, and less traumatic nature make it a technique that may take precedence over ERCP in ambiguous cases.

Utility of MRCP in clinical decision making of suspected choledocholithiasis: An institutional analysis and literature review

BACKGROUND

The ideal treatment algorithm for suspected choledocholithiasis is not yet well defined. Imaging options include magnetic resonance cholangiopancreatography (MRCP), endoscopic retrograde cholangiopancreatography (ERCP), and intraoperative cholangiogram (IOC). MRCP is diagnostic, while the other two modalities can also be therapeutic. Each of these modalities for diagnosis and treatment carries its own set of risks, benefits, and institutional costs. We hypothesized that there would be a significant difference between the biochemical profiles and characteristics of patients who undergo ERCP vs. MRCP vs. operative intervention as the initial choice of treatment/imaging modality.

METHODS

We performed a retrospective review of the electronic medical records for all patients with a coded diagnosis of choledocholithiasis from 2011 to 2014. The initial diagnostic modality was assessed for each hospital encounter. The statistical characteristics of MRCP as compared to fluoroscopic imaging of the biliary tree (ERCP, IOC) were analyzed.

RESULTS

Overall, 527 hospital encounters were identified. Initial intervention included ERCP in 63%, MRCP in 12%, and cholecystectomy in 25% of patients. Patients undergoing cholecystectomy first, compared to MRCP or ERCP, tended to have lower values for alkaline phosphatase (P < 0.001) and AST (P = 0.002) as well as be of younger age (P < 0.0001). Of the patients that underwent MRCP as their initial procedure, 82% subsequently underwent either ERCP or laparoscopic cholecystectomy. In patients who underwent an initial MRCP followed by either ERCP or IOC, the predictive performance of MRCP was as follows: sensitivity = 0.90, specificity = 0.86, positive predictive value = 0.97, negative predictive value = 0.60, agreement (Cohen's Kappa) = 0.64.

CONCLUSIONS

There is a significant difference in the laboratory evaluation and demographics of patients undergoing ERCP, MRCP, and laparoscopic cholecystectomy. MRCP was followed with a more invasive test a majority of the time. Since MRCP did not change the management of patients with suspected choledocholithiasis, its utility in this patient population should be questioned. Further research is needed to better define the pretest characteristics which would predict which patients do not need further intervention after MRCP as well as defining the most cost-effective strategy.

Pediatric Body Magnetic Resonance Imaging

Magnetic resonance imaging (MRI) is a radiation-free imaging modality with excellent contrast resolution and multiplanar capabilities. Since ionizing radiation is an important concern in the pediatric population, MRI serves as a useful alternative to computed tomography (CT) and also provides additional clues to diagnosis, not discernible on other investigations. Magnetic resonance cholangiopancreatography (MRCP), urography, angiography, enterography, dynamic multiphasic imaging and diffusion-weighted imaging provide wealth of information. The main limitations include, long scan time, need for sedation/anesthesia, cost and lack of widespread availability. With the emergence of newer sequences and variety of contrast agents, MRI has become a robust modality and may serve as a one-stop shop for both anatomical and functional information.

IgG4-related sclerosing cholangitis: all we need to know

Our knowledge and experience of IgG4-related sclerosing cholangitis (ISC) have expanded in the last decade. ISC is one of the common organ manifestations of IgG4-related disease (IgG4-RD); approximately 60 % of patients with this systemic condition have ISC in the proximal and/or distal bile ducts. ISC needs to be discriminated from primary sclerosing cholangitis, cholangiocarcinoma, and other rare forms of lymphoplasmacytic cholangiopathy (e.g., follicular cholangitis and sclerosing cholangitis with granulocytic epithelial lesions). Its diagnosis requires a multidisciplinary approach, in which serology, histology, and imaging play crucial roles. Treatments with high-dose corticosteroids typically lead to the rapid and consistent induction of disease remission. Another promising therapeutic approach is B-cell depletion with rituximab. Although disease relapse is relatively common, provided that appropriate treatments are administered, ISC is considered a "benign" disease with a low risk of liver failure and biliary malignancy. Its molecular pathology is characterized by Th2-dominant immune reactions, regulatory T-cell activation, and CCL1-CCR8 interactions. Particular subsets of B cells such as plasmablasts and regulatory B cells also expand. A recent global proteomic study demonstrated that three significantly activated immunological cascades in ISC were all B-cell- or immunoglobulin-related (Fc-gamma receptor-mediated phagocytosis, B-cell receptor signaling pathway, and Fc-epsilon receptor I signaling pathway), suggesting the crucial roles of B cells in the underlying immune reactions. Despite the expansion of our knowledge of the pathophysiology of ISC, the exact role of IgG4 remains unclear. A better understanding of its immunopathology will offer some potential drug targets for this emerging biliary disease.

Magnetic Resonance Imaging of Abdominal and Pelvic Pain in the Pregnant Patient

The utility of MR imaging in evaluating abdominal and pelvic pain in the pregnant patient is discussed. Details regarding the indications, technical aspects, and imaging findings of various common abdominal and pelvic abnormalities in pregnancy are reviewed.

Accuracy of magnetic resonance cholangiography compared to operative endoscopy in detecting biliary stones, a single center experience and review of literature

AIM: To compare diagnostic sensitivity, specificity and accuracy of magnetic resonance cholangiopancreatography (MRCP) without contrast medium and endoscopic ultrasound (EUS)/endoscopic retrograde cholangiopancreatography (ERCP) for biliary calculi.

METHODS: From January 2012 to December 2013, two-hundred-sixty-three patients underwent MRCP at our institution, all MRCP procedure were performed with the same machinery. In two-hundred MRCP was done for pure hepatobiliary symptoms and these patients are the subjects of this study. Among these two-hundred patients, one-hundred-eleven (55.5%) underwent ERCP after MRCP. The retrospective study design consisted in the systematic revision of all images from MRCP and EUS/ERCP performed by two radiologist with a long experience in biliary imaging, an experienced endoscopist and a senior consultant in Hepatobiliopancreatic surgery. A false positive was defined an MRCP showing calculi with no findings at EUS/ERCP; a true positive was defined as a concordance between MRCP and EUS/ERCP findings; a false negative was defined as the absence of images suggesting calculi at MRCP with calculi localization/extraction at EUS/ERCP and a true negative was defined as a patient with no calculi at MRCP ad at least 6 mo of asymptomatic follow-up. Biliary tree dilatation was defined as a common bile duct diameter larger than 6 mm in a patient who had an in situ gallbladder. A third blinded radiologist who examined the MRCP and ERCP data reviewed misdiagnosed cases. Once obtained overall data on sensitivity, specificity, accuracy, positive predictive value (PPV) and negative predictive value (NPV) we divided patients in two groups composed of those having concordant MRCP and EUS/ERCP (Group A, 72 patients) and those having discordant MRCP and EUS/ERCP (Group B, 20 patients). Dataset comparisons had been made by the Student’s t-test and χ² when appropriate.

RESULTS: Two-hundred patients (91 men, 109 women, mean age 67.6 years, and range 25-98 years) underwent MRCP. All patients attended regular follow-up for at least 6 mo. Morbidity and mortality related to MRCP were null. MRCP was the only exam performed in 89 patients because it did show only calculi into the gallbladder with no signs of the presence of calculi into the bile duct and symptoms resolved within a few days or after colecistectomy. The patients remained asymptomatic for at least 6 mo, and we assumed they were true negatives. One hundred eleven (53 men, 58 women, mean age 69 years, range 25-98 years) underwent ERCP following MRCP. We did not find any difference between the two groups in terms of race, age, and sex. The overall median interval between MRCP and ERCP was 9 d. In detecting biliary stones MRCP Sensitivity was 77.4%, Specificity 100% and Accuracy 80.5% with a PPV of 100% and NPV of 85%; EUS showed 95% sensitivity, 100% specificity, 95.5% accuracy with 100% PPV and 57.1% NPV. The association of EUS with ERCP performed at 100% in all the evaluated parameters. When comparing the two groups, we did not find any statistically significant difference regarding age, sex, and race. Similarly, we did not find any differences regarding the number of extracted stones: 116 stones in Group A (median 2, range 1 to 9) and 27 in Group B (median 2, range 1 to 4). When we compared the size of the extracted stones we found that the patients in Group B had significantly smaller stones: 14.16 ± 8.11 mm in Group A and 5.15 ± 2.09 mm in Group B; 95% confidence interval = 5.89-12.13, standard error = 1.577; P < 0.05. We also found that in Group B there was a significantly higher incidence of stones smaller than 5 mm: 36 in Group A and 18 in Group B, P < 0.05.

CONCLUSION: Major finding of the present study is that choledocholithiasis is still under-diagnosed in MRCP. Smaller stones (< 5 mm diameter) are hardly visualized on MRCP.

Diagnostic value of magnetic resonance cholangiopancreatography in choledocholithiasis

AIM: To evaluate the diagnostic accuracy of magnetic resonance cholangiopancreatography (MRCP) in patients with choledocholithiasis.

METHODS: We systematically searched MEDLINE, EMBASE, Web of Science, and Cochrane databases for studies reporting on the sensitivity, specificity and other accuracy measures of diagnostic effectiveness of MRCP for detection of common bile duct (CBD) stones. Pooled analysis was performed using random effects models, and receiver operating characteristic curves were generated to summarize overall test performance. Two reviewers independently assessed the methodological quality of studies using standards for reporting diagnostic accuracy and quality assessment for studies of diagnostic accuracy tools.

RESULTS: A total of 25 studies involving 2310 patients with suspected choledocholithiasis and 738 patients with CBD stones met the inclusion criteria. The average inter-rater agreement on the methodological quality checklists was 0.96. Pooled analysis of the ability of MRCP to detect CBD stones showed the following effect estimates: sensitivity, 0.90 (95%CI: 0.88-0.92, χ² = 65.80; P < 0.001); specificity, 0.95 (95%CI: 0.93-1.0, χ² = 110.51; P < 0.001); positive likelihood ratio, 13.28 (95%CI: 8.85-19.94, χ² = 78.95; P < 0.001); negative likelihood ratio, 0.13 (95%CI: 0.09-0.18, χ² = 6.27; P < 0.001); and diagnostic odds ratio, 143.82 (95%CI: 82.42-250.95, χ² = 44.19; P < 0.001). The area under the receiver operating characteristic curve was 0.97. Significant publication bias was not detected (P = 0.266).

CONCLUSION: MRCP has high diagnostic accuracy for the detection of choledocholithiasis. MRCP should be the method of choice for suspected cases of CBD stones.

Endoscopic ultrasound versus magnetic resonance cholangiopancreatography for common bile duct stones

BACKGROUND

Endoscopic ultrasound (EUS) and magnetic resonance cholangiopancreatography (MRCP) are tests used in the diagnosis of common bile duct stones in patients suspected of having common bile duct stones prior to undergoing invasive treatment. There has been no systematic review of the accuracy of EUS and MRCP in the diagnosis of common bile duct stones using appropriate reference standards.

OBJECTIVES

To determine and compare the accuracy of EUS and MRCP for the diagnosis of common bile duct stones.

SEARCH METHODS

We searched MEDLINE, EMBASE, Science Citation Index Expanded, BIOSIS, and Clinicaltrials.gov until September 2012. We searched the references of included studies to identify further studies and of systematic reviews identified from various databases (Database of Abstracts of Reviews of Effects (DARE), Health Technology Assessment (HTA), Medion, and ARIF (Aggressive Research Intelligence Facility)). We did not restrict studies based on language or publication status, or whether data were collected prospectively or retrospectively.

SELECTION CRITERIA

We included studies that provided the number of true positives, false positives, false negatives, and true negatives for EUS or MRCP. We only accepted studies that confirmed the presence of common bile duct stones by extraction of the stones (irrespective of whether this was done by surgical or endoscopic methods) for a positive test, and absence of common bile duct stones by surgical or endoscopic negative exploration of the common bile duct or symptom free follow-up for at least six months for a negative test, as the reference standard in people suspected of having common bile duct stones. We included participants with or without prior diagnosis of cholelithiasis; with or without symptoms and complications of common bile duct stones, with or without prior treatment for common bile duct stones; and before or after cholecystectomy. At least two authors independently screened abstracts and selected studies for inclusion.

DATA COLLECTION AND ANALYSIS

Two authors independently collected the data from each study. We used the bivariate model to obtain pooled estimates of sensitivity and specificity.

MAIN RESULTS

We included a total of 18 studies involving 2366 participants (976 participants with common bile duct stones and 1390 participants without common bile duct stones). Eleven studies evaluated EUS alone, and five studies evaluated MRCP alone. Two studies evaluated both tests. Most studies included patients who were suspected of having common bile duct stones based on abnormal liver function tests; abnormal transabdominal ultrasound; symptoms such as obstructive jaundice, cholangitis, or pancreatitis; or a combination of the above. The proportion of participants who had undergone cholecystectomy varied across studies. Not one of the studies was of high methodological quality. For EUS, the sensitivities ranged between 0.75 and 1.00 and the specificities ranged between 0.85 and 1.00. The summary sensitivity (95% confidence interval (CI)) and specificity (95% CI) of the 13 studies that evaluated EUS (1537 participants; 686 cases and 851 participants without common bile duct stones) were 0.95 (95% CI 0.91 to 0.97) and 0.97 (95% CI 0.94 to 0.99). For MRCP, the sensitivities ranged between 0.77 and 1.00 and the specificities ranged between 0.73 and 0.99. The summary sensitivity and specificity of the seven studies that evaluated MRCP (996 participants; 361 cases and 635 participants without common bile duct stones) were 0.93 (95% CI 0.87 to 0.96) and 0.96 (95% CI 0.90 to 0.98). There was no evidence of a difference in sensitivity or specificity between EUS and MRCP (P value = 0.5). From the included studies, at the median pre-test probability of common bile duct stones of 41% the post-test probabilities (with 95% CI) associated with positive and negative EUS test results were 0.96 (95% CI 0.92 to 0.98) and 0.03 (95% CI 0.02 to 0.06). At the same pre-test probability, the post-test probabilities associated with positive and negative MRCP test results were 0.94 (95% CI 0.87 to 0.97) and 0.05 (95% CI 0.03 to 0.09).

AUTHORS' CONCLUSIONS

Both EUS and MRCP have high diagnostic accuracy for detection of common bile duct stones. People with positive EUS or MRCP should undergo endoscopic or surgical extraction of common bile duct stones and those with negative EUS or MRCP do not need further invasive tests. However, if the symptoms persist, further investigations will be indicated. The two tests are similar in terms of diagnostic accuracy and the choice of which test to use will be informed by availability and contra-indications to each test. However, it should be noted that the results are based on studies of poor methodological quality and so the results should be interpreted with caution. Further studies that are of high methodological quality are necessary to determine the diagnostic accuracy of EUS and MRCP for the diagnosis of common bile duct stones.

Adult bile duct strictures: role of MR imaging and MR cholangiopancreatography in characterization

Bile duct strictures in adults are secondary to a wide spectrum of benign and malignant pathologic conditions. Benign causes of bile duct strictures include iatrogenic causes, acute or chronic pancreatitis, choledocholithiasis, primary sclerosing cholangitis, IgG4-related sclerosing cholangitis, liver transplantation, recurrent pyogenic cholangitis, Mirizzi syndrome, acquired immunodeficiency syndrome cholangiopathy, and sphincter of Oddi dysfunction. Malignant causes include cholangiocarcinoma, pancreatic adenocarcinoma, and periampullary carcinomas. Rare causes include biliary inflammatory pseudotumor, gallbladder carcinoma, hepatocellular carcinoma, metastases to bile ducts, and extrinsic bile duct compression secondary to periportal or peripancreatic lymphadenopathy. Contrast material-enhanced magnetic resonance (MR) imaging with MR cholangiopancreatography is extremely helpful in the noninvasive evaluation of patients with obstructive jaundice, an obstructive pattern of liver function, or incidentally detected biliary duct dilatation. Some of these conditions may show characteristic findings at MR imaging-MR cholangiopancreatography that help in making a definitive diagnosis. Although endoscopic retrograde cholangiopancreatography with tissue biopsy or surgery is needed for the definitive diagnosis of many of these strictures, certain MR imaging characteristics of the narrowed segment (eg, thickened wall, long-segment involvement, asymmetry, indistinct outer margin, luminal irregularity, hyperenhancement relative to the liver parenchyma) may favor a malignant cause. Awareness of the various causes of bile duct strictures in adults and familiarity with their appearances at MR imaging-MR cholangiopancreatography are important for accurate diagnosis and optimal patient management.

Magnetic resonance imaging of pancreatitis: An update

Magnetic resonance (MR) imaging plays an important role in the diagnosis and staging of acute and chronic pancreatitis and may represent the best imaging technique in the setting of pancreatitis due to its unmatched soft tissue contrast resolution as well as non-ionizing nature and higher safety profile of intravascular contrast media, making it particularly valuable in radiosensitive populations such as pregnant patients, and patients with recurrent pancreatitis requiring multiple follow-up examinations. Additional advantages include the ability to detect early forms of chronic pancreatitis and to better differentiate adenocarcinoma from focal chronic pancreatitis. This review addresses new trends in clinical pancreatic MR imaging emphasizing its role in imaging all types of acute and chronic pancreatitis, pancreatitis complications and other important differential diagnoses that mimic pancreatitis.

Magnetic resonance cholangiopancreatography: utilization and usefulness in suspected choledocholithiasis

BACKGROUND

The aim of this study was to evaluate the role of magnetic resonance cholangiopancreatography in cases of suspected choledocholithiasis.

METHODS

Suitable candidates were recruited from a database of all consecutive patients who underwent magnetic resonance cholangiopancreatography between March 2009 and December 2012. Patients were stratified into low, medium and high risk for choledocholithiasis by assessing clinical symptoms, liver function tests and ultrasonography. True negatives and false positives were calculated based on endoscopic retrograde cholangiopancreatography, intraoperative cholangiogram and clinical follow-up.

RESULTS

Of 201 magnetic resonance cholangiopancreatography investigations conducted, choledocholithiasis was diagnosed in 37 (18%) patients. In total, there was one false negative and three false positives. Total sensitivity and specificity values were 97% and 98%, respectively. These values were highest among low-risk patients (100% for both sensitivity and specificity). By initially opting for magnetic resonance imaging in suitable moderate- and high-risk patients, unnecessary endoscopic retrograde cholangiopancreatography procedures were avoided in 61% and 65% of patients, respectively.

CONCLUSION

Magnetic resonance cholangiopancreatography for patients with suspected choledocholithiasis yields high sensitivity and specificity. Given its reduced risk profile and relative ease of administration, magnetic resonance cholangiopancreatography is a necessary tool for the assessment of choledocholithiasis with the capacity to rival gold standard diagnostic techniques and help reduce the number of unnecessary interventional procedures.

Magnetic resonance cholangiography in the assessment and management of biliary complications after OLT

Despite advances in patient and graft management, biliary complications (BC) still represent a challenge both in the early and delayed period after orthotopic liver transplantation (OLT). Because of unspecific clinical presentation, imaging is often mandatory in order to diagnose BC. Among imaging modalities, magnetic resonance cholangiography (MRC) has gained widespread acceptance as a tool to represent the reconstructed biliary tree noninvasively, using both the conventional technique (based on heavily T2-weighted sequences) and contrast-enhanced MRC (based on the acquisition of T1-weighted sequences after the administration of hepatobiliary contrast agents). On this basis, MRC is generally indicated to: (1) avoid unnecessary procedures of direct cholangiography in patients with a negative examination and/or identify alternative complications; and (2) provide a road map for interventional procedures or surgery. As illustrated in the review, MRC is accurate in the diagnosis of different types of biliary complications, including anastomotic strictures, non-anastomotic strictures, leakage and stones.

Role of MRCP in predicting difficulty of bile duct intubation during ERCP

AIM: To evaluate the value of some anatomical indexes on MRCP images in the prediction of difficulty of bile duct intubation during ERCP.

METHODS: Clinical data for 93 patients who had undergone MRCP before ERCP treatment from November 2011 to June 2012 at the Affiliated Hospital of Qingdao University Medical College were retrospectively analyzed. The patients were classified into two groups, group A (n = 30), in which bile duct intubation during ERCP was difficult, and group B (n = 60), in which bile duct intubation was easy. Five main indexes, including common bile duct diameter, pancreatic duct diameter, separation angle between the common bile duct and the pancreatic duct, the distance between the duodenal wall and the confluence of the common bile duct and the pancreatic duct, and the distance between the openings of the common bile duct and the pancreatic duct in the duodenum, were measured on MRCP images and compared between the two groups to find indexes which can forecast difficulty of bile duct intubation during ERCP.

RESULTS: The success rate of ERCP was 98.92%. There were significant differences between the two groups in the common bile duct diameter and separation angle between the common bile duct and the pancreatic duct (4.48 ±1.27 vs 6.73 ± 2.32; 25.89 ± 14.40 vs 43.37 ± 24.88, both P < 0.05).

CONCLUSION: MRCP may be helpful to predict difficulty of bile duct intubation during ERCP and to choose the best treatment for patients with biliary tract disease.

[Endoscopic retrograde cholangiopancreatography at a regional hospital of the Instituto Mexicano del Seguro Social, 2002-2011: risk factors and complications]

BACKGROUND

Endoscopic retrograde cholangiopancreatography (ERCP) is a valuable study in the approach to diseases of the biliary and pancreatic ducts. It was first used for diagnostic purposes, but today its use is mainly therapeutic. It can present a variety of complications.

AIMS

To determine the frequency of complications and the risk factors associated with ERCP.

MATERIAL AND METHODS

A prolective study was carried out to analyze ERCP that was performed on 1.145 patients over a 10-year period of time (2.002-2.011). Complications were determined at the time of the procedure, through the personal communication of relatives, and/or when the patient was admitted to the emergency room. Follow-up was carried out for one month after ERCP in the out-patient service of the Department of Gastroenterology. Complications were evaluated with a multiple logistic regression model.

RESULTS

The sample included 1.145 patients. Mean age was 55,3 years (SD=18,7; CI 95%: 54,2-56,3). Women made up 60,5% (n=693) of the study participants. Therapeutic endoscopy was performed in 51,0% of the total number of procedures. Complications presented in 2,1% (n=24) of the patients; the most frequent was hemorrhage (n=14, 1,2%), followed by acute pancreatitis (n=6, 0,5%), respiratory distress (n=3, 0,3%), and cholangitis (n=1, 0,1%). There was a 1,4 times higher complication risk in patients that underwent precut/sphincterotomy, adjusted by age (CI 95%: OR 1,02-5,43; p=0,045).

CONCLUSIONS

This study shows a complication frequency similar to that published by other authors. However, this figure could be further reduced if ERCP were performed only for therapeutic purposes by highly qualified endoscopy physicians.

Pancreaticobiliary disorders: comparison between magnetic resonance cholangiopancreatography images before and after fentanyl injection

OBJECTIVE

This study was designed to determine the effects of intravenous fentanyl on magnetic resonance cholangiopancreatography image quality in the treatment of pancreaticobiliary disorders.

MATERIALS AND METHODS

Forty consecutive patients referred for the evaluation of pancreaticobiliary disorders underwent magnetic resonance cholangiopancreatography in the coronal and oblique-coronal planes before and after fentanyl injection (every 2 up to 9 min). The images were analyzed qualitatively and quantitatively. Diameter and signal intensity were measured at the widest point and distal to the common bile duct and main pancreatic duct.

RESULTS

The mean common bile duct diameters at the widest and distal points and mean pancreatic duct diameter were measured 7.53, 4.72, and 2.14 and 8.33, 5.35, and 2.57 before and after fentanyl injection, respectively. Mean signal intensity at the widest and distal point of the common bile duct and mean pancreatic duct signal intensity measured 278, 199, and 113 and 296, 218, and 121 before and after fentanyl injection, respectively. Minor improvements in image quality were detected qualitatively.

CONCLUSION

Fentanyl injection improves images qualitatively and quantitatively. In agreement with previous studies, our results confirm the beneficial effects of fentanyl as a simple adjunct to traditional magnetic resonance cholangiopancreatography.

Imaging of pregnant and lactating patients: part 2, evidence-based review and recommendations

OBJECTIVE

The objectives of this article are to discuss the current evidence-based recommendations regarding the use of diagnostic imaging in the evaluation of pulmonary embolism, appendicitis, urolithiasis, and cholelithiasis during pregnancy.

CONCLUSION

Diagnostic imaging should be performed during pregnancy only with an understanding of the maternal and fetal risks and benefits, the comparative advantages of different modalities, and the unique anatomic and physiologic issues associated with pregnancy.

MR imaging of the abdomen and pelvis in infants, children, and adolescents

Recent developments in magnetic resonance (MR) imaging have profoundly changed the investigation of abdominal and pelvic disease in pediatrics. Motion reduction techniques, such periodically rotated overlapping parallel lines with enhanced reconstruction, or PROPELLER, have resulted in reliable imaging with quiet breathing. Faster imaging sequences minimize artifact and allow for more efficient studies. Diffusion-weighted imaging has become increasingly important in the evaluation of neoplastic disease, depicting disease with increased cellularity and helping to differentiate benign from malignant masses. MR enterography helps visualize intra- and extraluminal bowel pathologic conditions. MR cholangiopancreatography can depict congenital and acquired causes of pancreatic and biliary abnormalities. MR urography is an effective technique for a one-stop-shop evaluation of structural urinary tract abnormality and renal function. Three-dimensional acquisitions allow volumetric display of structures from multiple angles. Specialized techniques allow quantification of iron and fat in the viscera in children with hemolytic anemia and obesity, respectively. This article covers current techniques and strategies to perform and optimize MR imaging of the abdomen and pelvis in infants, children, and adolescents and describes important practical applications.

Impact of magnetic resonance cholangiography in managing liver-transplanted patients: preliminary results of a clinical decision-making study

PURPOSE

This study was performed to assess the role of magnetic resonance cholangiography (MRC) in the clinical decision-making process of referring physicians when managing liver-transplanted patients.

MATERIALS AND METHODS

Over a 6-month period, 21 liver-transplanted patients with a suspected biliary complication were referred for MRC. Referring physicians were asked to prospectively state, before and after MRC, the leading diagnosis; the level of confidence (on a 0-100% scale); the most appropriate diagnostic/therapeutic plan. Data analysis assessed was the diagnostic yield of MRC; the proportion of change in the leading diagnosis; the therapeutic efficacy (i.e. proportion of change in the initial diagnostic/therapeutic plan); the diagnostic thinking efficacy (i.e., gain in diagnostic confidence). Statistical significance was assessed with the Mann-Whitney U test. MRC accuracy was also calculated.

RESULTS

Data analysis showed a diagnostic yield of 85.7%; a proportion of change in leading diagnosis of 19.0%; a therapeutic efficacy of 42.8%; a diagnostic thinking efficacy for concordant and discordant leading diagnoses of 18.8% and 78.7%, respectively (p<0.01). MRC accuracy was 92.3%.

CONCLUSIONS

MRC significantly increased the diagnostic confidence, irrespective of the concordance between pre- and posttest diagnoses. Moreover, MRC determined a change in patient management in a significant proportion of cases, leading to clinical benefits.

Biliary, pancreatic, and hepatic imaging for the general surgeon. Surg Clin North Am. 2011;91:59-92. [PMID: 21184901 DOI: 10.1016/j.suc.2010.10.005]

Technologic advancements have allowed imaging modalities to become more useful in the diagnosis of hepatobiliary and pancreatic disorders. Computed tomography scanners now use multidetector row technology with contrast-delayed imaging for quicker and more accurate imaging. Magnetic resonance imaging with cholangiopancreatography can more clearly delineate liver lesions and the biliary and pancreatic ducts, and can diagnose pathologic conditions early in their course. Newer technologies, such as single-operator cholangioscopy and endoscopic ultrasonography, have sometimes shown superiority to traditional modalities. This article addresses the literature regarding available imaging techniques in the diagnosis and treatment of common surgical hepatobiliary and pancreatic diseases.

What should be done with a dilated bile duct? Curr Gastroenterol Rep. 2010;12:150-156. [PMID: 20424988 DOI: 10.1007/s11894-010-0094-3]

Current methods for imaging the biliary tree include ultrasound, CT, MRI, endoscopic retrograde cholangiography, and endoscopic ultrasound (EUS). Bile duct abnormalities may be identified during evaluation of patient symptoms or laboratory abnormalities, or incidentally during imaging for another problem. Biliary dilatation, when identified, may be separated into obstructive or nonobstructive causes. Clinical presentation should guide decisions on which, if any, additional investigations are necessary. Choledocholithiasis is the most common cause of obstructive dilatation and frequently requires decompression. Nonobstructive causes include cystic dilatation, aging, and possibly post-cholecystectomy state. Data are limited regarding the yield of further investigations in patients with incidentally identified modest ductal dilatation without symptoms or laboratory abnormalities. Additional investigations are more likely to identify clinically relevant findings in patients with more pronounced dilatation. EUS is highly accurate, low-invasive, and useful in this setting, whereas ERC should be reserved for cases likely to require therapeutic intervention.

Gallbladder imaging

The treatment of gallbladder disease has been revolutionized by improvements in laparoscopic surgery as well as endoscopic and radiologic interventional techniques. Therapeutic success is dependent on accurate radiologic assessment of gallbladder pathology. This article describes recent technical advances in ultrasonography, multidetector computed tomography, magnetic resonance imaging, positron emission tomography, and scintigraphy, which have significantly improved the accuracy of noninvasive imaging of benign and malignant gallbladder disease. The imaging findings of common gallbladder disorders are presented, and the role of each of the imaging modalities is placed in perspective for optimizing patient management.

The value of pre-operative magnetic resonance cholangiopancreatography (MRCP) in management of patients with gall stones

OBJECTIVE

To analyze influence of pre-operative MRCP on the management of patients with gall stones.

PATIENTS & METHODS

This prospective randomized study was carried on 250 patients who underwent laparoscopic cholecystectomy within 3 years. In group I, pre-operative MRCP was performed in 125 patients with age range of 18-62 years. Group II included 125 patients managed by laparoscopic cholecystectomy without doing pre-operative MRCP with age range of 21-65 years.

RESULTS

In group I; pre-operative MRCP screening revealed clinically silent CBD stones in 5 patients (4%), accessory cystic duct in 2 (1.6%), abnormal insertion of cystic duct in 1 (0.8%). Postoperatively, bile duct injury was inflected in 1 patient in group I. On the other hand, there were 2 patients with bile duct injury and 5 patients with residual stones in group II. There was a statistically significant increase of post-operative complications in group II (p <or= 0.5).

CONCLUSIONS

MRCP is diagnostically useful in management of patients with gall stones prior to laparoscopic cholecystectomy and its routine use can reduce the incidence of post-operative complications.

Multimodality imaging of hepato-biliary disorders in pregnancy: a pictorial essay

Hepato-biliary disorders are rare complications of pregnancy, but they may be severe, with high fetal and maternal morbidity and mortality. Imaging is, therefore, essential in the rapid diagnosis of some of these conditions so that appropriate, life-saving treatment can be administered. This pictorial essay illustrates the multimodality imaging features of pregnancy-induced hepato-biliary disorders, such as acute fatty liver of pregnancy, preeclamsia and eclampsia, and HELLP syndrome, as well as those conditions which occur in pregnancy but are not unique to it, such as viral hepatitis, Budd-Chiari syndrome, focal hepatic lesions, biliary sludge, cholecystolithiasis, and choledocholithiasis.

The diagnostic MRCP examination: overcoming technical challenges to ensure clinical success

The magnetic resonance cholangiopancreatography (MRCP) examination has all but replaced the diagnostic endoscopic retrograde cholangiopancreatography (ERCP) examination for imaging the biliary tree and pancreatic ducts in many practical aspects of the clinical setting. Despite this increase in popularity, many magnetic resonance imaging (MRI) radiographers still find aspects of the MRCP examination quite challenging. The aim of this tutorial paper is to provide useful technical advice on how to overcome such perceived challenges and thus produce a successful diagnostic MRCP examination. This paper will be of interest to novice MRI radiographers who are at the beginning of their learning curve in MRCP examination. Other MRI radiographers who are interested in practical tips for protocol variations may also find the paper useful.

Imaging the pregnant patient for nonobstetric conditions: algorithms and radiation dose considerations

Use of diagnostic imaging studies for evaluation of pregnant patients with medical conditions not related to pregnancy poses a persistent and recurring dilemma. Although a theoretical risk of carcinogenesis exists, there are no known risks for development of congenital malformations or mental retardation in a fetus exposed to ionizing radiation at the levels typically used for diagnostic imaging. An understanding of the effects of ionizing radiation on the fetus at different gestational stages and the estimated exposure dose received by the fetus from various imaging modalities facilitates appropriate choices for diagnostic imaging of pregnant patients with nonobstetric conditions. Other aspects of imaging besides radiation (ie, contrast agents) also carry potential for fetal injury and must be taken into consideration. Imaging algorithms based on a review of the current literature have been developed for specific nonobstetric conditions: pulmonary embolism, acute appendicitis, urolithiasis, biliary disease, and trauma. Imaging modalities that do not use ionizing radiation (ie, ultrasonography and magnetic resonance imaging) are preferred for pregnant patients. If ionizing radiation is used, one must adhere to the principle of using a dose that is as low as reasonably achievable after a discussion of risks versus benefits with the patient.

MR cholangiopancreatography in children: feasibility, safety, and initial experience

BACKGROUND

The indications for MR cholangiopancreatography (MRCP) in children, and its safety and findings, might differ from those in adults and are not well described.

OBJECTIVE

To investigate the safety, feasibility, and accuracy of MRCP in children.

MATERIALS AND METHODS

We reviewed all prospective MRCP reports, noting the indication, the use of secretin, endoscopic retrograde cholangiopancreatography (ERCP) findings, and patient outcomes. Two readers reviewed each MRCP study by consensus to rate duct visualization and compare pancreatic duct sizes before and after secretin administration (paired t-test). The likelihood of a normal versus an abnormal MRCP study was compared by gender, pancreatitis as the primary indication, secretin use, and whether ERCP was performed (Fisher's exact test), as well as age (t-test).

RESULTS

A total of 85 MRCP studies were performed in children (mean age 10.3 years), most commonly for evaluation of pancreatitis (n=47, 55%); 41 (48%) used secretin and 39 (46%) used a negative oral contrast agent. Of the 85 studies, 72 (85%) had excellent image quality and 43 were normal. ERCP was performed after 16 of the 85 MRCP studies (19%); the diagnoses were concordant with those of MRCP in 13 (81%). There were 42 abnormal MRCP studies, and these were more likely to be in girls (P=0.03) and in children who had undergone ERCP (P<0.01). Secretin and the negative oral contrast agent were well-tolerated. Secretin improved duct visualization (P<0.001).

CONCLUSION

MRCP safely and accurately depicted pancreaticobiliary anatomy in children. The use of secretin improved visualization of the pancreatic duct.

Management of severe acute pancreatitis: it's all about timing

PURPOSE OF REVIEW

This study provides an update on the treatment of severe acute pancreatitis (SAP) with emphasis on nutrition, infection-prophylaxis, biliary pancreatitis, surgical intervention and new randomized controlled trials.

RECENT FINDINGS

The most relevant new insights are: (i) early enteral nutrition in SAP is not only capable of reducing infectious complications but may also reduce mortality; (ii) there is increasing evidence that antibiotic-prophylaxis is not capable of preventing infectious complications in SAP; (iii) probiotic-prophylaxis is being considered as an alternative with promising experimental results; (iv) in biliary pancreatitis, early endoscopic retrograde cholangiography with sphincterotomy (within 48 h) is beneficial in case of ampullary obstruction, although it may be withheld in the event of negative endoscopic ultrasound; (v) surgical intervention for infected (peri-)pancreatic necrosis is increasingly being postponed; (vi) minimally invasive strategies are being considered as a full alternative for necrosectomy by laparotomy in infected (peri-)pancreatic necrosis; (vii) the Atlanta classification should no longer be used to describe computed tomography findings in acute pancreatitis; and (viii) only five randomized controlled trials of patients with acute pancreatitis are currently registered in the international trial registries.

SUMMARY

Timing of intervention is becoming increasingly important in SAP management.

Choledocholithiasis: Evolving standards for diagnosis and management

Cholelithiasis, one of the most common medical conditions leading to surgical intervention, affects approximately 10 % of the adult population in the United States. Choledocholithiasis develops in about 10%-20% of patients with gallbladder stones and the literature suggests that at least 3%-10% of patients undergoing cholecystectomy will have common bile duct (CBD) stones.

CBD stones may be discovered preoperatively, intraoperatively or postoperatively Multiple modalities are available for assessing patients for choledocholithiasis including laboratory tests, ultrasound, computed tomography scans (CT), and magnetic resonance cholangiopancreatography (MRCP). Intraoperative cholangiography during cholecystectomy can be used routinely or selectively to diagnose CBD stones.

The most common intervention for CBD stones is ERCP. Other commonly used interventions include intraoperative bile duct exploration, either laparoscopic or open. Percutaneous, transhepatic stone removal other novel techniques of biliary clearance have been devised. The availability of equipment and skilled practitioners who are facile with these techniques varies among institutions. The timing of the intervention is often dictated by the clinical situation.