Magnetic resonance imaging in evaluation of the common bile duct

Risk of Heart Disease after Cholecystectomy: A Nationwide Population-Based Cohort Study in South Korea

The aim of the study is to evaluate the risk of heart disease in individuals who underwent cholecystectomy. This was a retrospective cohort study using the National Health Insurance Service database of South Korea. A total of 146,928 patients who underwent cholecystectomy and 268,502 age- and sex-matched controls were compared. Multivariate Cox proportional hazard regression analysis was used to estimate the hazard ratio (HR) and 95% confidence interval (CI) for heart disease after cholecystectomy. In results, a previous history of cholecystectomy increased the risk of heart disease (congestive heart failure [CHF], myocardial infarction [MI], atrial fibrillation [AF]) (adjusted HR [aHR]: 1.40, 95% CI: [1.36–1.44]). The increased risk was particularly seen for CHF (1.22 [1.16–1.29]) but not for MI and AF (p > 0.05). In the subgroup analyses, cholecystectomy was associated with an increased risk of MI in patients aged <65 years (1.49 [1.16–1.92] and 1.18 [1.05–1.35] in patients aged 40–49 and 50–64 years, respectively), but not in those aged ≥ 65 years (0.932 [0.838–1.037]). Moreover, the risk of MI was increased in patients without diabetes mellitus (DM) (1.16 [1.06–1.27]); however, it was decreased in patients with DM (0.83 [0.72–0.97]). In contrast, cholecystectomy did not modify the risk of AF in the subgroup analyses (all p > 0.05). In conclusion, a history of cholecystectomy is associated with an increased risk of CHF. Cholecystectomy may increase the risk of MI in the younger population without DM. These findings suggest that the alteration of bile metabolism and homeostasis might be potentially associated with the development of some heart diseases.

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.

Bariatric surgery is not contraindicated in obese patients suffering from glycogen storage disease type IXa. A case report with follow-up at three years

INTRODUCTION

Glucose storage disease type IXa (GSD IXa) is an uncommon condition presenting with childhood onset hepatomegaly, growth retardation, and often, fasting ketosis and hypoglycemia. Despite its benign course, the lack of dietary counseling may favor uncontrolled weight gain. We investigated the efficacy of bariatric surgery in one 17 years old female suffering from GSD IXa and morbid obesity.

PRESENTATION OF CASE

The diagnosis was GSD type IXa in a patient with a body mass index (BMI) of 45.5 kg/m². Onset of hypoglycemia was reported twice each month. She was treated her implanting an adjustable gastric banding through laparoscopy. Three years after surgery the patient presents a BMI of 30.1 kg/m² and an excess of weight loss (EWL) of 71.1%. Only once, following surgery, she had to deflate her band to allow a faster transit of food through her stomach, thus reaching a prompt euglycemic condition, due to an incoming hypoglycemic crisis.

DISCUSSION

Laparoscopic adjustable gastric banding (LAGB) is one of the most used approaches to treat morbid obesity. It is a restrictive procedure unable to affect the absorption of any nutrient, presenting a very low intra and perioperative complication rate. In our GSD IXa patient, it offered a prompt modification of food intake restriction whenever requested, thus avoiding hypoglycemia.

CONCLUSION

LAGB is effective in determining weight loss without inducing significant side effects or worsening hypoglycemia, in this morbid obese patient, suffering from GSD type IXa.

A radiological diary of gallstone migration in a patient with acute pancreatitis

This case report is interesting in radiologically showing migration of stones from the gallbladder via the biliary tree and into the gastrointestinal tract.

Magnetic resonance imaging of the common bile duct to exclude choledocholithiasis

BACKGROUND

Prior to cholecystectomy it is important to assess the common duct for choledocholithiasis. Given that a proportion of common duct stones will pass without incident and that methods of removal of these stones are potentially morbid, it would be very useful to have a test that identified only those stones that need intervention. The present study was designed to assess whether a negative magnetic resonance cholangiopancreaticogram (MRCP) is able to reliably exclude clinically relevant common duct stones.

METHODS

A retrospective analysis on all patients with cholelithiasis, who underwent MRCP, between November 2001 and May 2003, for suspected choledocholithiasis, was performed. Patients were considered to have no clinically relevant choledocholithiasis if they had a negative MRCP for choledocholithiasis, and were not readmitted to the hospital with complications of choledocholithiasis within a minimum of 3 months after treatment for their cholelithiasis.

RESULTS

The MRCP was negative for choledocholithiasis in 74% of patients (60/81). The MRCP missed clinically relevant choledocholithiasis in only two patients, and had a positive predictive value of 0.95 and a negative predictive value of 0.97 for choledocholithiasis.

CONCLUSION

In patients with strong indications for choledocholithiasis MRCP is able to reliably exclude clinically relevant choledocholithiasis and is therefore recommended as the preoperative diagnostic imaging tool of choice.

The efficacy of magnetic resonance cholangiography for the evaluation of patients with suspected choledocholithiasis before laparoscopic cholecystectomy

BACKGROUND

Endoscopic retrograde cholangiography is the most commonly utilized tool for the identification of common bile duct stones (CBDS) before laparoscopic cholecystectomy, whereas the role of magnetic resonance cholangiography (MRC) for patient evaluation before laparoscopic cholecystectomy is currently undefined.

METHODS

We prospectively evaluated the efficacy of MRC for the identification of CBDS among patients with high risk for choledocholithiasis. Patient selection was based on clinical, sonographic, and laboratory criteria. Standard cholangiograms were obtained when possible for verification of MRC results.

RESULTS

Ninety-nine patients underwent evaluation with preoperative MRC. CBDS was visualized in 30% of patients. MRC sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were 85%, 90%, 77%, 94%, and 89%, respectively.

CONCLUSIONS

MRC is useful for the evaluation of patients with suspected choledocholithiasis. Advantages of MRC include its noninvasive nature, ease of application, and accuracy in identifying and estimating the size of CBDS. Application of MRC in this setting reduces the need for diagnostic endoscopic retrograde cholangiography. Future investigations should be directed at the development of cost-effective utilization strategies for MRC application.

Routine intravenous cholangiography, selective ERCP, and endoscopic treatment of bile duct stones before laparoscopic cholecystectomy

BACKGROUND

No procedure has yet been identified as the standard for the detection and management of choledocholithiasis in patients undergoing laparoscopic cholecystectomy.

METHODS

A prospective study involved 1305 patients undergoing elective laparoscopic cholecystectomy. Intravenous cholangiography was performed on all patients except those with jaundice or cholangitis, acute pancreatitis, or allergy to contrast material. Patients underwent endoscopic retrograde cholangiography (ERC) and endoscopic sphincterotomy when there was a strong suspicion of choledocholithiasis, positive or inconclusive findings on intravenous cholangiography or allergy to contrast material with signs of possible choledocholithiasis. Intraoperative cholangiography was performed when patients did not undergo ERC or intravenous cholangiography and whenever the surgeon was in doubt about biliary anatomy or biliary clearance.

RESULTS

Two hundred thirty-one patients (17.7%) were referred for preoperative ERC; 14 of them were referred for open surgery because of failure of ERC or sphincterotomy. Only 54 patients underwent intraoperative cholangiography. Bile duct stones, detected in 186 cases (14.2%) (68 of which were asymptomatic), were removed before surgery in 162 cases (87.1%) and during surgery in 20 (10.7%). Self-limited pancreatitis occurred in 3.6% of the patients after sphincterotomy. Laparoscopic cholecystectomy was performed in 98.7% of the cases. The conversion rate was 8% if sphincterotomy had been performed previously, and 3% after standard laparoscopic cholecystectomy (p < 0.001). The morbidity rate was 5% and the mortality rate 0.08%. During the follow-up period 4 patients had retained stones that were treated endoscopically.

CONCLUSIONS

Preoperative ERC followed by laparoscopy is the best approach to treatment of patients with cholecystolithiasis and suspected choledocholithiasis.

Utility of magnetic resonance cholangiography in the evaluation of biliary obstruction

BACKGROUND

Evaluation of suspected biliary obstruction has traditionally involved a variety of imaging modalities including ultrasound, CT, and invasive cholangiography. These techniques have limitations because of poor visualization of intraductal stones (ultrasound and CT) and the need for an invasive procedure (ERCP and percutaneous transhepatic cholangiography). Magnetic resonance cholangiography (MRC) is a noninvasive imaging modality that provides good visualization of the hepatobiliary system. The aim of the present study was to determine the utility of MRC in evaluating patients with suspected biliary obstruction.

STUDY DESIGN

One hundred forty-three patients were identified with suspected acute biliary obstruction and underwent MRC. Patient selection was based on clinical criteria including an elevation in serum liver chemistries or evidence of biliary ductal dilatation on conventional imaging. MRC was performed using a half-Fourier acquisition single-shot turbo spin-echo sequence involving single breath-hold rapid image acquisition. A final diagnosis was determined in each patient based on invasive cholangiography, findings at surgery, and clinical course.

RESULTS

Of the 143 patients, 73 had an obstructing biliary lesion. A malignant process was identified in 25 patients with final diagnoses of pancreatic cancer (n = 15), ampullary cancer (n = 4), cholangiocarcinoma (n = 3), and hepatic or nodal metastases (n = 3). MRC correctly identified biliary obstruction in all these patients and accurately identified the level of biliary obstruction in 24 of 25 patients. Based on the MRC images alone, a malignant process was suspected in 21 of the 25 patients. Forty patients were found to have common bile duct stones and eight patients had a benign distal bile duct stricture. MRC correctly identified common bile duct stones in 37 patients with one false-positive exam (sensitivity = 92%; specificity = 99%). MRC also correctly identified distal biliary strictures in eight patients. In the remaining 70 patients, no definite biliary obstruction was identified by MRC, and in all patients the absence of mechanical obstruction was confirmed by invasive cholangiography or overall clinical course.

CONCLUSIONS

This study demonstrates that MRC is able to accurately identify the level and cause of biliary obstruction in both malignant and benign disease. MRC may prove to be an important noninvasive tool in preoperative evaluation of patients with suspected biliary obstruction and identification of patients most likely to benefit from an invasive radiologic or surgical procedure.

Mangafodipir trisodium: effects on T2- and T1-weighted MR cholangiography

The purpose of this study was to determine the effects of mangafodipir trisodium on heavily T2-weighted magnetic resonance cholangiography (MRC) images and on functional T1-weighted MRC. Pre- and post-mangafodipir trisodium heavily T2-weighted MRC and fat-suppressed T1-weighted three-dimensional (3D) gradient-echo MRC images were obtained in a patient with a prior cholecystectomy and a long cystic duct remnant that had apparent biliary stasis. Multiplanar reconstructed images were created. The precontrast T2-weighted MRC showed a long cystic duct remnant and a normal common bile duct (CBD). The postcontrast T2-weighted MRC showed loss of CBD signal, but persistent signal in the cystic duct remnant due to biliary stasis. Post-mangafodipir T1-weighted 3D gradient-echo images showed the main right and left hepatic ducts, but the cystic duct was not depicted. Conventional T2-weighted MRC sequences should not be obtained after administering mangafodipir trisodium because this contrast agent decreases the T2 and therefore the signal intensity of bile within normally functioning bile ducts. Functional MRC images can be acquired by using a post-mangafodipir T1-weighted technique.