Magnetic resonance cholangiopancreatography versus endoscopic ultrasound for diagnosis of choledocholithiasis: an updated systematic review and meta-analysis

Clinical and Investigative Approach to Recurrent Acute Pancreatitis

Recurrent acute pancreatitis (RAP) is a complex syndrome that presents variably, with many cases remaining idiopathic after thorough diagnostics. For evaluating structural etiologies, endoscopic ultrasound and MR cholangiopancreatography are preferred over endoscopic retrograde cholangiopancreatography (ERCP) given their more favorable risk profile and sensitivity. The diagnostic work-up remains paramount since treatment should focus on addressing underlying causes such as early cholecystectomy for gallstone pancreatitis. As more etiologic factors are uncovered, such as genetic susceptibility, causality becomes more nuanced. Earlier enthusiasm for endoscopic sphincterotomy as a treatment for idiopathic RAP has been tempered by less favorable studies in recent years.

An App model that utilizes a logistic regression algorithm for predicting choledocholithiasis: A prospective clinical trial

INTRODUCTION AND AIM

The diagnostic yield of the current criteria for assigning the risk of choledocholithiasis (CL) is inaccurate. The aim of our work was to develop a logistic regression model for predicting CL diagnosis in patients catalogued as either intermediate or high risk for CL, according to the criteria of the American Society for Gastrointestinal Endoscopy (ASGE).

MATERIAL AND METHODS

We conducted an analytic, observational, cross-sectional study for evaluating the diagnostic yield of a logistic regression model in adults with intermediate or high risk for CL. A receiver operating characteristic (ROC) curve analysis was done to determine the best cutoff point for predicting the diagnosis of CL. Endoscopic retrograde cholangiopancreatography (ERCP) was utilized as the gold standard for diagnosing CL.

RESULTS

A total of 148 patients suspected of presenting with CL were studied. In our cohort, 71 had immediate risk and 77 had high risk. CL diagnosis was confirmed in 102 patients (69%). Our model showed an area under the curve (AUC) of 0.68. In patients with an intermediate risk for CL, the AUC value was 0.72 and the positive predictive value (PPV) was 70%. In patients with a high risk for CL, the AUC value was 0.78 and the PPV was 89%.

CONCLUSION

Our model appears to better predict the diagnosis of CL than the ASGE criteria for patients with an intermediate or high risk for the disease. Our model can guide clinical decisions in patients with suspected CL.

Magnetic resonance cholangiopancreatography at 5.0 T: quantitative and qualitative comparison with 3.0 T

BACKGROUND

This study aimed to assess the feasibility and performance of 5.0 T MRI in MR Cholangiopancreatography (MRCP) imaging compared to 3.0 T, focusing on detail visualization, signal-to-noise ratio (SNR), and image artifacts.

METHODS

A prospective study from May to October 2023 involved 20 healthy subjects and 19 with biliary dilation. Both groups underwent MRCP using 3.0 T and 5.0 T scanners. The detail visualization capability of the biliary tree and the SNR of the images were quantitatively evaluated. Two experienced MRI diagnostic physicians assessed the image artifacts qualitatively on a scale of 1 to 5. The t-test or Wilcoxon signed-rank test compared the quantitative results of biliary visualization and SNR between 3.0 T and 5.0 T scanners, while the Wilcoxon signed-rank test was used for comparing the level of image artifacts between the two scanners. The inter reader consistency was tested using Kappa test.

RESULTS

In both healthy subjects and those with biliary dilation, the 5.0 T group exhibited significantly higher numbers of biliary tree branches, along with greater total and maximum branch lengths, compared to the 3.0 T group (P<0.05). Although the maximum branch length was higher in the 5.0 T group among healthy subjects, this difference was not statistically significant (P = 0.053). No notable differences were observed in SNR and image artifact levels between the two groups across both field strengths (P>0.05).

CONCLUSIONS

MRCP at 5.0 T offers superior biliary tree visualization compared to 3.0 T. The performance regarding SNR and image artifacts between the two is relatively comparable.

Predictors of Choledocholithiasis in Cholecystectomy Patients and Their Cutoff Values and Prediction Model in Korea in Comparison with the 2019 ASGE Guidelines

Background/Aims

: In 2019, the American Society for Gastrointestinal Endoscopy (ASGE) established clinical predictors for choledocholithiasis. Our study was designed to evaluate these predictors within the Korean clinical context, establish cutoff values, and develop a predictive model.

Methods

: This retrospective study analyzed patients who underwent laparoscopic cholecystectomy. The relationships between choledocholithiasis and predictors including age, blood tests, and imaging findings were assessed through univariate and multivariate logistic regression analyses. We established Korean cutoff values for these predictors and developed a scoring system for choledocholithiasis using a multivariate logistic regression. The performance of this scoring system was then compared with that of the 2019 ASGE guidelines through a receiver operating characteristic curve.

Results

: We established Korean cutoff values for age (>70 years), alanine aminotransferase (>26.5 U/L), aspartate aminotransferase (>28.5 U/L), gamma-glutamyl transferase (GGT; >82.5 U/L), alkaline phosphatase (ALP; >77.5 U/L), and total bilirubin (>0.95 mg/dL). In the multivariate analysis, only age >70 years, GGT >77.5 U/L, ALP >77.5 U/L, and common bile duct dilatation remained significant. We then developed a new Korean risk stratification model from the multivariate analysis, with an area under the curve of 0.777 (95% confidence interval, 0.75 to 0.81). Our model was stratified into the low-risk, intermediate-risk, and high-risk groups with the scores being <1.0, 1.0-5.5, and >5.5, respectively.

Conclusions

: Predictors of choledocholithiasis in cholecystectomy patients and their cutoff values in Korean should be adjusted and further studies are needed to develop appropriate guidelines.

Endoscopic Ultrasound and Intraductal Ultrasound in the Diagnosis of Biliary Tract Diseases: A Narrative Review

Endoscopic ultrasound (EUS) and intraductal ultrasound (IDUS) play very important roles in the field of biliary tract disease. Because of their excellent spatial resolution, the detection of small lesions and T- or N-staging of tumors have become possible. Additionally, contrast-enhanced EUS and the new imaging technique of detective flow imaging are reported to be useful for differential diagnosis. Furthermore, EUS-guided tissue acquisition is used not only for pathological diagnosis but also to collect tissue samples for cancer genome profiling. This review provides an overview of diagnosis utilizing the features and techniques of EUS and IDUS.

Pancreaticobiliary Maljunction with Repeated Pancreatitis Due to Protein Plugs in a Short Period

A 70-year-old woman was admitted to the hospital 1 month prior to presentation with acute pancreatitis due to pancreaticobiliary maljunction. After discharge, she was referred for elevated hepatobiliary enzyme levels. She was diagnosed with an acute pancreatitis flare-up. Computed tomography revealed dilation of the common duct compared to the previous admission. Considering the protein plug formation as the cause, endoscopic retrograde cholangiopancreatography (ERCP) was performed after improvement. ERCP revealed a defect in the duct, suspected to be caused by protein plugs, which were removed using a balloon after endoscopic papillary balloon dilatation. An analysis revealed that this component was a protein. No recurrence of pancreatitis was observed after the treatment.

Convolutional neural network for identifying common bile duct stones based on magnetic resonance cholangiopancreatography

AIMS

To develop an auto-categorization system based on machine learning for three-dimensional magnetic resonance cholangiopancreatography (3D MRCP) to detect choledocholithiasis from healthy and symptomatic individuals.

MATERIALS AND METHODS

3D MRCP sequences from 254 cases with common bile duct (CBD) stones and 251 cases with normal CBD were enrolled to train the 3D Convolutional Neural Network (3D-CNN) model. Then 184 patients from three different hospitals (91 with positive CBD stone and 93 with normal CBD) were prospectively included to test the performance of 3D-CNN.

RESULTS

With a cutoff value of 0.2754, 3D-CNN achieved the sensitivity, specificity, and accuracy of 94.51%, 92.47%, and 93.48%, respectively. In the receiver operating characteristic curve analysis, the area under the curve (AUC) for the presence or absence of CBD stones was 0.974 (95% CI, 0.940-0.992). There was no significant difference in sensitivity, specificity, and accuracy between 3D-CNN and radiologists. In addition, the performance of 3D-CNN was also evaluated in the internal test set and the external test set, respectively. The internal test set yielded an accuracy of 94.74% and AUC of 0.974 (95% CI, 0.919-0.996), and the external test set yielded an accuracy of 92.13% and AUC of 0.970 (95% CI, 0.911-0.995).

CONCLUSIONS

An artificial intelligence-assisted diagnostic system for CBD stones was constructed using 3D-CNN model for 3D MRCP images. The performance of 3D-CNN model was comparable to that of radiologists in diagnosing CBD stones. 3D-CNN model maintained high performance when applied to data from other hospitals.

Performance of European and American Societies of Gastrointestinal Endoscopy Guidelines for Prediction of Choledocholithiasis in Patients with Acute Biliary Pancreatitis

Background and Objectives: Up to one-third of patients with acute biliary pancreatitis also present with choledocholithiasis. Guidelines from the European Society of Gastrointestinal Endoscopy (ESGE) and the American Society for Gastrointestinal Endoscopy (ASGE) for investigating suspected choledocholithiasis suggest endoscopic retrograde cholangiopancreatography in patients with high-likelihood (ESGE)/high-probability (ASGE) predictors and endoscopic ultrasound in those with intermediate-likelihood (ESGE)/intermediate-probability (ASGE) predictors. Although both guidelines are similar, they are not identical. Furthermore, these algorithms were mainly developed from cohorts of patients without pancreatitis and are therefore poorly validated in a subset of patients with acute pancreatitis. We aimed to assess the performance of the ESGE and ASGE algorithms for the prediction of choledocholithiasis in patients with acute biliary pancreatitis. Materials and Methods: This was a retrospective analysis of 86 consecutive patients admitted to a tertiary referral centre in the year 2020 due to acute biliary pancreatitis. Results: Choledocholithiasis was confirmed in 29/86 (33.7%) of patients (13 with endoscopic retrograde cholangiopancreatography and 16 with endoscopic ultrasound). All 10/10 (100%) ESGE high-likelihood and 14/19 (73.7%) ASGE high-probability patients had choledocholithiasis. Only 19/71 (26.8%) patients with ESGE intermediate likelihood and 15/67 (22.4%) with ASGE intermediate probability had choledocholithiasis. Only 8/13 (61.5%) patients with the ASGE high-probability predictor of dilated common bile duct plus bilirubin > 68.4 µmol/mL had choledocholithiasis. Since this predictor is not considered high likelihood by ESGE, this resulted in a superior specificity of the European compared to the American guideline (100% vs. 91.2%). Following the American instead of the European guidelines would have resulted in five unnecessary endoscopic retrograde cholangiopancreatographies and five unnecessary endoscopic ultrasound examinations. Conclusions: This retrospective analysis suggests that the European guidelines may perform better than the American guidelines at predicting choledocholithiasis in the setting of acute pancreatitis. This was because dilated common bile duct plus bilirubin > 68.4 µmol/mL was not a reliable predictor for persistent bile duct stones.

Endoscopic Ultrasound in Pancreatology: Focus on Inflammatory Diseases and Interventions

Background

Endoscopic ultrasound (EUS) is a main tool in pancreatology for both diagnosis and therapy. It allows minimally invasive differentiation of various diseases, with a minimal degree of inflammation or anatomic variations. EUS also enables interventional direct access to the pancreatic parenchyma and the retroperitoneal space, the pancreatic duct, the pancreatic masses, cysts, vascular structures for diagnostic and therapeutic purposes.

Summary

This review aimed to summarize the new developments of EUS in the field of pancreatology, with special interest on inflammation and interventions. EUS enables way to perform pseudocyst drainage, necrosectomy, transenteral drainage and transenteric access of the main pancreatic duct, or the direct visualization or therapy of vascular structures adjacent to the pancreas.

Key Messages

EUS has a deep impact on pancreatology, and the development of new diagnostic and interventional approaches to the retroperitoneal space and the pancreas has increased in the last years exponentially, allowing minimal invasive diagnostics and therapy and avoiding surgery and percutaneous therapy.