The relative roles of magnetic resonance cholangiopancreatography (MRCP) and endoscopic ultrasound in diagnosis of common bile duct calculi: a critically appraised topic

Sensitivity and Specificity of Magnetic Resonance Cholangiopancreatography versus Endoscopic Ultrasonography against Endoscopic Retrograde Cholangiopancreatography in Diagnosing Choledocholithiasis: The Indonesian Experience

BACKGROUND/AIMS

Biliary stone disease is one of the most common conditions leading to hospitalization. In addition to endoscopic retrograde cholangiopancreatography (ERCP), endoscopic ultrasonography (EUS) and magnetic resonance cholangiopancreatography (MRCP) are required in diagnosing choledocholithiasis. This study aimed to compare the sensitivity and specificity of EUS and MRCP against ERCP in diagnosing choledocholithiasis.

METHODS

This retrospective study was conducted after prospective collection of data involving 62 suspected choledocholithiasis patients who underwent ERCP from June 2013 to August 2014. Patients were divided into two groups. The first group (31 patients) underwent EUS and the second group (31 patients) underwent MRCP. Then, ERCP was performed in both groups. Sensitivity, specificity, and diagnostic accuracy of EUS and MRCP were determined by comparing them to ERCP, which is the gold standard.

RESULTS

The male to female ratio was 3:2. The mean ages were 47.25 years in the first group and 52.9 years in the second group. Sensitivity, specificity, accuracy, positive predictive value, and negative predictive value for EUS were 96%, 57%, 87%, 88%, and 80% respectively, and for MRCP were 81%, 40%, 68%, 74%, and 50%, respectively.

CONCLUSIONS

EUS is a better diagnostic tool than MRCP for diagnosing choledocholithiasis.

Updated guideline on the management of common bile duct stones (CBDS)

Common bile duct stones (CBDS) are estimated to be present in 10-20% of individuals with symptomatic gallstones. They can result in a number of health problems, including pain, jaundice, infection and acute pancreatitis. A variety of imaging modalities can be employed to identify the condition, while management of confirmed cases of CBDS may involve endoscopic retrograde cholangiopancreatography, surgery and radiological methods of stone extraction. Clinicians are therefore confronted with a number of potentially valid options to diagnose and treat individuals with suspected CBDS. The British Society of Gastroenterology first published a guideline on the management of CBDS in 2008. Since then a number of developments in management have occurred along with further systematic reviews of the available evidence. The following recommendations reflect these changes and provide updated guidance to healthcare professionals who are involved in the care of adult patients with suspected or proven CBDS. It is not a protocol and the recommendations contained within should not replace individual clinical judgement.

The value of magnetic resonance cholangiopancreatography for the exclusion of choledocholithiasis

OBJECTIVE

To investigate the ability of Magnetic resonance cholangiopancreatography (MRCP) to exclude choledocholithiasis (CDL) in symptomatic patients.

MATERIAL AND METHODS

Patients suspected of choledocholithiasis who underwent MRCP from 2008 through 2013 in a population based study at the National University Hospital of Iceland were retrospectively analysed, using ERCP and/or intraoperative cholangiography as a gold standard diagnosis for CDL.

RESULTS

Overall 920 patients [66% women, mean age 55 years (SD 21)] underwent MRCP. A total of 392 patients had a normal MRCP of which 71 underwent an ERCP investigation demonstrating a CBD stone in 29 patients. A normal MRCP was found to have a 93% negative predictive value (NPV) and 89% probability of having no CBD stone demonstrated as well as no readmission due to gallstone disease within six months following MRCP. During a 6-month follow-up period of the 321 patients who did not undergo an ERCP nine (2.8%) patients were readmitted with right upper quadrant pain and elevated liver tests which later normalised with no CBD stone being demonstrated, three (0.9%) patients were readmitted with presumed gallstone pancreatitis, two (0.6%) patients were readmitted with cholecystitis and two (0.6%) patients were lost to follow-up. Seven patients of those 321 underwent an intraoperative cholangiography (IOC) and all were negative for CBD stones. For the sub-group requiring ERCP following a normal MRCP the NPV was 63%.

CONCLUSION

Our results support the use of MRCP as a tool for exclusion of choledocholithiasis with the potential to reduce the amount of unnecessary ERCP procedures.

Treatment of biliary tract stones after gastrectomy in the era of laparoscopic cholecystectomy

BACKGROUND

The incidence of biliary tract stones has widely been reported to be high after gastrectomy. Treatment of biliary tract stones in post-gastrectomy patients was examined retrospectively, particularly minimally invasive therapy with laparoscopic cholecystectomy for gallbladder stones and endoscopic bile duct lithotomy for common bile duct stones.

METHODS

Treatment of 122 post-gastrectomy patients with biliary tract stones was examined retrospectively from 1995 to April 2015.

RESULTS

Symptomatic biliary tract stones were found in 3.7% of post-gastrectomy patients. The frequency of bile duct stones was higher in post-gastrectomy patients with gallbladder stones (44%) than in the nongastrectomy patients (11%). Laparoscopic cholecystectomy was carried out in 84% of the patients with gallbladder stones. Endoscopic bile duct lithotomy was feasible in 89% of patients with common bile duct stones.

CONCLUSIONS

Laparoscopic cholecystectomy was feasible for removing gallbladder stones after gastrectomy. Endoscopic bile duct lithotomy followed by laparoscopic cholecystectomy was a good option for patients in whom endoscopic intervention could be performed. On the other hand, choledochoenterostomy could be a good option for patients in whom endoscopic bile duct lithotomy cannot be performed, particularly considering the risk of recurrent bile duct stones.

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.

Body mass index, cholecystitis, cholelithiasis, pancreatitis and imaging of common bile duct stones

PURPOSE

Studies to date have not investigated whether body mass index (BMI) affects the sensitivity and specificity of magnetic resonance cholangiopancreatography (MRCP). The purpose of this study was to investigate the effect of BMI and also concomitant pancreatitis, cholecystitis and cholelithiasis on the sensitivity and specificity of MRCP.

MATERIALS AND METHODS

Between January 2004 and December 2011, 185 patients were included in the study and divided into 3 groups according to BMI as normal, overweight or obese. Both MRCP and endoscopic retrograde cholangiopancreatography (ERCP) were performed in all patients. ERCP was accepted as the "gold standard." The accuracy, sensitivity and specificity values of the 3 groups were calculated to determine any effects on the results of the MRCP.

RESULTS

Before separating into groups according to BMI, the statistical results for MRCP in the detection of stone disease were as follows: specificity 74.3%, sensitivity 81.7% and accuracy 79%. After dividing the patients into 3 groups according to BMI, the specificity of stone detection with MRCP in the normal-weight group was 93.8% but decreased to 65.5% in the overweight group and to 72% in the obese group. The sensitivity of stone detection with MRCP in the normal-weight group was 85.2% but decreased to 75% in the overweight group and increased to 88.9% in the obese group. The accuracy was 88.3% in the normal-weight group but decreased to 71.6% in the overweight group and to 81.9% in the obese group.

CONCLUSION

Our study showed that MRCP performance was decreased in the overweight and obese groups.

Gallstone pancreatitis: a review

Gallstone disease is the most common cause of acute pancreatitis in the Western world. In most cases, gallstone pancreatitis is a mild and self-limiting disease, and patients may proceed without complications to cholecystectomy to prevent future recurrence. Severe disease occurs in about 20% of cases and is associated with significant mortality; meticulous management is critical. A thorough understanding of the disease process, diagnosis, severity stratification, and principles of management is essential to the appropriate care of patients presenting with this disease. This article reviews these topics with a focus on surgical management, including appropriate timing and choice of interventions.

[Critically appraised topics (CATs): a new publishing opportunity in Radiología]

Physicians need fast access to quality information about the best diagnostic tests and treatments in each case. To meet this need, a new publishing format has emerged. Critically appraised topics (CATs) are elaborated following the five steps of evidence-based medicine. CATs are structured summaries of research articles that deal with a specific clinical query, presenting a critical evaluation of the best evidence available to support the validity of the available options. CATs have proven useful in teaching evidence-based radiology and this publishing format is becoming more common. Radiology CATs can be found on medical websites and in journals, including those dedicated to general medicine as well as those specifically dedicated to radiology. Radiología encourages the publication of CATs because we consider that they can be useful for daily decision making.

EUS in exploring the etiology of mild acute biliary pancreatitis with a negative finding of biliary origin by conventional radiological methods

BACKGROUND AND AIM

Conventional radiological methods, including transcutaneous ultrasonography (US), computed tomography (CT), and magnetic resonance cholangiopancreatography (MRCP) are non-invasive and recommended for the detection of etiologies of acute biliary pancreatitis (ABP). There are still, however, a number of patients whose etiologies cannot be found by these methods. The value of endoscopic ultrasound (EUS) for this population is still unknown. The aim of the present study was to evaluate the role of EUS in exploring the unknown etiology of mild ABP.

METHODS

The data from patients with mild ABP admitted to Changhai Hospital, Shanghai, China, from June 2006 to December 2009 were retrospectively collected, and the results of the imaging methods in detecting biliary disorders were analyzed.

RESULTS

A total of 223 patients with mild ABP underwent both US and CT. Of these, 106 underwent additional MRCP. There were still 37 patients with unknown biliary etiologies, even after the use of the conventional methods mentioned earlier. EUS was conducted in 33 of these patients. Abnormalities associated with the etiology of mild ABP were found in 14 cases (42.4%) confirmed by subsequent endoscopic retrograde cholangiopancreatography, with biliary stones in 11 cases, biliary sludge in two cases, and ampullary adenocarcinoma in one case.

CONCLUSION

The results suggest that EUS is helpful in the identification of the etiology of mild biliary pancreatitis when conventional radiological imaging is negative or equivocal.

Value-based insurance design: barriers to implementation in radiology

Expensive and steadily rising health care costs without a concomitant increase in quality have generated a search for solutions to fund health care in the United States. Recent health care reforms and proposals on the agenda have spurred debate about alternative payment plans for health care. Much of the talk centers on imaging, which is a fast-growing and expensive component of health care. Value-based insurance design (VBID), a "clinically sensitive" means of sharing the cost of health care, has been proposed as a means to control the runaway costs of health care management including diagnostic testing. A corollary of pay-for-performance initiatives in which physician incentives are aligned with evidence-based medical practices, VBID seeks to increase patient incentives to comply with evidence-based health care consumption. We previously reviewed the principles of VBID and provided examples of VBID in practice using diabetes management as a model, as well as suggested some areas in diagnostic testing that lend themselves to VBID benefit design. In this article, we summarize the barriers to implementation and outline potential solutions, with particular regard to radiology.

Diagnostic accuracy of endoscopic ultrasonography in patients with inconclusive magnetic resonance imaging diagnosis of biliopancreatic abnormalities

AIM

To determine the sensitivity and specificity of endoscopic ultrasonography (EUS) in patients with inconclusive magnetic resonance imaging/magnetic resonance cholangiopancreatography (MRI/MRCP) in pancreatobiliary abnormalities.

METHODS

During 10 months, patients with pancreatobiliary diseases referred to endoscopic retrograde cholangiopancreatography (ERCP) because of inconclusive MRI/MRCP diagnosis were scheduled to undergo endoscopic ultrasonography. Patients were divided into four major groups: patients with (i) resectable periampullary neoplasms who were referred to a surgeon, (ii) unresectable periampullary cancer who underwent ERCP for biliary stenting, (iii) bile duct stone who were referred to ERCP for stone extraction, and (iv) normal pancreatobiliary tract. Reference standards for comparison were ERCP, surgery, a biopsy confirming malignancy, or the clinical course during follow up (at least 12 months) in cases without evidences of malignancy.

RESULTS

One hundred and seven patients (51 men; mean [SD] age 60.0 [15.5]) were included in the study. Final diagnoses were common bile duct (CBD) stone (n = 24), periampullary neoplasms (n = 46), others (n = 23) and no pathologic findings (n = 14). EUS determined the staging for clinical decision-making in 47 patients with neoplasms which showed that tumors in 34 patients (79.1%) were unresectable (advanced stage). After EUS, 47 patients (43.9%) did not require ERCP. The accuracy of EUS for the diagnosis of CBD stone and periampullary neoplasms were 96.3% and 99.1%, respectively.

CONCLUSIONS

EUS is a useful modality in cases of inconclusive MRI/MRCP indicating pancreatobiliary disorders.

BILIARY AND PANCREATIC DISEASE IN PREGNANCY

Pregnancy is a physiological condition that affects all organs. Diseases unrelated to pregnancy may present coincidentally during pregnancy or may be exacerbated by pregnancy, and may increase maternal and/or fetal morbidity or mortality. Compared with many other systems, the changes within the biliary tree and pancreas are relatively minimal. However, pregnancy is associated with an increased likelihood of cholelithiasis, which can have significant implications for the parturient.

Comparison of different MRCP techniques for the depiction of biliary complications after liver transplantation

OBJECTIVE

Biliary strictures after liver transplantation are common. We aimed to compare different magnetic resonance cholangiopancreatography (MRCP) sequences with regard to their diagnostic accuracy in depicting anastomotic stenoses (AST), ischaemic-type biliary lesions (ITBL) and cholelithiasis.

METHODS

In patients with clinically suspected biliary obstruction after liver transplantation, MRCP was performed at 1.5 T using two-dimensional (2D) single-shot RARE, 2D T2-weighted (T2w) HASTE, 2D TrueFISP and 3D T2w TSE RESTORE sequences. The presence and localisation of lesions were assessed for each sequence independently and all sequences together. Endoscopic retrograde cholangiopancreatography (ERCP) served as the "gold standard".

RESULTS

Biliary strictures were detected with a sensitivity of 96% by MRCP and most accurately depicted when all sequences were analysed together. AST was visualised with highest sensitivity on TrueFISP and 3D T2w TSE sequences (79%). For ITBL highest sensitivity was found with the HASTE sequence (81%). Highest sensitivity for filling defects was revealed by the 3D T2w TSE sequence (54%). Receiver operating characteristic (ROC) curve/area under the curve (AUC) analysis revealed the best results for the 3D T2w TSE sequence.

CONCLUSION

Our results underline the value of different MRCP sequence types for the depiction of biliary lesions. A clinical protocol consisting of different sequences may be helpful depending on the clinical question and the likely underlying abnormality.

Endoscopic ultrasound in the evaluation of pancreaticobiliary disorders

The close proximity of the endoscopic ultrasound probe to the pancreas coupled with the ability to perform fine needle aspiration has made endoscopic ultrasound an extremely important technique for the evaluation of both benign and malignant pancreaticobiliary disorders. In parallel to the widespread importance of diagnostic endoscopic ultrasound, the therapeutic and interventional applications of this procedure are expanding and may become a major breakthrough in the management of pancreaticobiliary diseases. This article focuses on the utility and recent advances of endoscopic ultrasound in the diagnostic evaluation pancreaticobiliary disorders and analyses the data of well established interventional procedures such as celiac plexus neurolysis and pseudocyst drainage. Moreover, the more innovative procedures, such endoscopic ultrasound-guided biliary and pancreatic ducts access and drainage and the experimental use of direct endoscopic ultrasound-guided therapy of both solid and cystic pancreatic lesions will also be reviewed.

Possible biliary disease: diagnostic performance of high-spatial-resolution isotropic 3D T2-weighted MRCP

PURPOSE

To retrospectively assess the diagnostic performance of magnetic resonance cholangiopancreatography (MRCP) performed by using a high-spatial-resolution isotropic three-dimensional (3D) fast-recovery fast spin-echo (FSE) sequence with parallel imaging for the evaluation of possible biliary disease.

MATERIALS AND METHODS

This HIPAA-compliant study was approved by the institutional review board; informed consent was waived. Ninety-five patients (58 female, 37 male; mean age, 51 years; range, 15-91 years) underwent MRCP by using the respiratory-triggered isotropic 3D fast-recovery FSE sequence and endoscopic or percutaneous direct visualization between March 2003 and June 2007. Two independent readers evaluated the MRCP images for strictures, dilatation, and intraductal filling defects. Sensitivity, specificity, and interobserver agreement (kappa statistics) were determined.

RESULTS

The respective sensitivity and specificity for strictures, dilatation, and intraductal filling defects (all choledocholithiasis) were 86% (40 of 47) and 94% (45 of 48), 98% (57 of 58) and 100% (37 of 37), and 68% (19 of 28) and 97% (65 of 67) for reader 1 and 88% (41 of 47) and 94% (45 of 48), 96% (56 of 58) and 100% (37 of 37), and 75% (21 of 28) and 99% (66 of 67) for reader 2. The sensitivity for stones larger than 3 mm was 94% (15 of 16) for reader 1 and 100% (16 of 16) for reader 2, whereas the sensitivity for stones 3 mm or smaller was 33% (four of 12) for reader 1 and 42% (five of 12) for reader 2. Agreement between readers was good to excellent, with kappa values of 0.76, 0.85, and 0.98 for strictures, dilatation, and choledocholithiasis, respectively.

CONCLUSION

MRCP by using the respiratory-triggered isotropic 3D fast-recovery FSE sequence with parallel imaging demonstrates excellent diagnostic capabilities for possible biliary disease, although it is limited for stones 3 mm or smaller in size.

Acute pancreatitis: etiology, clinical presentation, diagnosis, and therapy

Acute pancreatitis is a relatively common disease that affects about 300,000 patients per annum in America with a mortality of about 7%. About 75% of pancreatitis is caused by gallstones or alcohol. Other important causes include hypertriglyceridemia, medication toxicity, trauma from endoscopic retrograde cholangiopancreatography, hypercalcemia, abdominal trauma, various infections, autoimmune, ischemia, and hereditary causes. In about 15% of cases the cause remains unknown after thorough investigation. This article discusses the causes, diagnosis, imaging findings, therapy, and complications of acute pancreatitis.