Incidental biliary dilation in the era of the opiate epidemic: High prevalence of biliary dilation in opiate users evaluated in the Emergency Department

Sphincterotomy for biliary sphincter of Oddi disorder and idiopathic acute recurrent pancreatitis: the RESPOnD longitudinal cohort

OBJECTIVE

Sphincter of Oddi disorders (SOD) are contentious conditions in patients whose abdominal pain, idiopathic acute pancreatitis (iAP) might arise from pressurisation at the sphincter of Oddi. The present study aimed to measure the benefit of sphincterotomy for suspected SOD.

DESIGN

Prospective cohort conducted at 14 US centres with 12 months follow-up. Patients undergoing first-time endoscopic retrograde cholangiopancreatography (ERCP) with sphincterotomy for suspected SOD were eligible: pancreatobiliary-type pain with or without iAP. The primary outcome was defined as the composite of improvement by Patient Global Impression of Change (PGIC), no new or increased opioids and no repeat intervention. Missing data were addressed by hierarchal, multiple imputation scheme.

RESULTS

Of 316 screened, 213 were enrolled with 190 (89.2%) of these having a dilated bile duct, abnormal labs, iAP or some combination. By imputation, an average of 122/213 (57.4% (95% CI 50.4% to 64.4%)) improved; response rate was similar for those with complete follow-up (99/161, 61.5% (54.0% to 69.0%)); of these, 118 (73.3%) improved by PGIC alone. Duct size, elevated labs and patient characteristics were not associated with response. AP occurred in 37/213 (17.4%) at a median of 6 months post ERCP and was more likely in those with a history of AP (30.9% vs 2.9%, p<0.0001).

CONCLUSION

Nearly 60% of patients undergoing ERCP for suspected SOD improve, although the contribution of a placebo response is unknown. Contrary to prevailing belief, duct size and labs are poor response predictors. AP recurrence was common and like observations from prior non-intervention cohorts, suggesting no benefit of sphincterotomy in mitigating future AP episodes.

Imaging of Biliary Tree Abnormalities

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

Rise in First-Time ERCP for Benign Indications >1 Year After Cholecystectomy Is Associated With Worse Outcomes

BACKGROUND & AIMS

Greater availability of less invasive biliary imaging to rule out choledocholithiasis should reduce the need for diagnostic endoscopic retrograde cholangiopancreatography (ERCP) in patients who have a remote history of cholecystectomy. The primary aims were to determine the incidence, characteristics, and outcomes of individuals who undergo first-time ERCP >1 year after cholecystectomy (late-ERCP).

METHODS

Data from a commercial insurance claim database (Optum Clinformatics) identified 583,712 adults who underwent cholecystectomy, 4274 of whom underwent late-ERCP, defined as first-time ERCP for nonmalignant indications >1 year after cholecystectomy. Outcomes were exposure and temporal trends in late-ERCP, biliary imaging utilization, and post-ERCP outcomes. Multivariable logistic regression was used to examine patient characteristics associated with undergoing late-ERCP.

RESULTS

Despite a temporal increase in the use of noninvasive biliary imaging (35.9% in 2004 to 65.6% in 2021; P < .001), the rate of late-ERCP increased 8-fold (0.5-4.2/1000 person-years from 2005 to 2021; P < .001). Although only 44% of patients who underwent late-ERCP had gallstone removal, there were high rates of post-ERCP pancreatitis (7.1%), hospitalization (13.1%), and new chronic opioid use (9.7%). Factors associated with late-ERCP included concomitant disorder of gut-brain interaction (odds ratio [OR], 6.48; 95% confidence interval [CI], 5.88-6.91) and metabolic dysfunction steatotic liver disease (OR, 3.27; 95% CI, 2.79-3.55) along with use of anxiolytic (OR, 3.45; 95% CI, 3.19-3.58), antispasmodic (OR, 1.60; 95% CI, 1.53-1.72), and chronic opioids (OR, 6.24; 95% CI, 5.79-6.52).

CONCLUSIONS

The rate of late-ERCP postcholecystectomy is increasing significantly, particularly in patients with comorbidities associated with disorder of gut-brain interaction and mimickers of choledocholithiasis. Late-ERCPs are associated with disproportionately higher rates of adverse events, including initiation of chronic opioid use.

Normal morphometry of the biliary tree in pediatric and adult populations: A systematic review and meta-analysis

PURPOSE

This study aimed to characterise the normal morphometry of the biliary tree in pediatric and adult populations, through a systematic review and meta-analysis.

METHODS

This study, conducted using the PRISMA guidelines and registered with PROSPERO, searched MEDLINE, EMBASE, SCOPUS and Web of Science databases up to October 2022, and updated to August 2023. Studies that reported extractable data on diameter and length of the right, left and common hepatic ducts (LHD, RHD and CHD), and common bile duct (CBD) were included. Quality of the included studies were assessed using the Anatomical Quality Assessment (AQUA) tool. Statistical analysis included subgroup analyses according to sex, age, geographical location, and imaging modality.

RESULTS

In total, 60 studies were included, of which 44 studies reported adequate data for meta-analysis on 23,796 subjects. Overall, the pooled mean diameter of the CBD was 4.69 mm (95 % CI: 4.28-5.11). Significant differences were found between pediatric (1.32 mm, 95 % CI: 1.03-1.61) and adult (4.97 mm, 95 % CI: 4.67-5.27) subjects, as well as US (3.82 mm, 95 % CI: 3.15-4.49) and other imaging modalities, including MRI (6.21 mm, 95 % CI: 4.85-7.57) and ERCP (7.24 mm, 95 % CI: 6.08-8.40). The CBD diameter measured significantly larger distally (5.20 mm, 95 % CI: 4.60-5.80) than proximally (4.01 mm, 95 % CI: 3.51-4.51).

CONCLUSIONS

The results obtained from this evidence-based study may guide the establishment of standardised reference values and ranges of the normal biliary tree in pediatric and adult populations and aid clinical understanding.

Sphincterotomy for Biliary Sphincter of Oddi Disorder and idiopathic Acute Recurrent Pancreatitis: THE RESPOND LONGITUDINAL COHORT

Objective

Sphincter of Oddi Disorders (SOD) are contentious conditions in patients whose abdominal pain, idiopathic acute pancreatitis (iAP) might arise from pressurization at the sphincter of Oddi. The present study aimed to measure the benefit of sphincterotomy for suspected SOD.

Design

Prospective cohort conducted at 14 U.S. centers with 12 months follow-up. Patients undergoing first-time ERCP with sphincterotomy for suspected SOD were eligible: pancreatobiliary-type pain with or without iAP. The primary outcome was defined as the composite of improvement by Patient Global Impression of Change (PGIC), no new or increased opioids, and no repeat intervention. Missing data were addressed by hierarchal, multiple imputation scheme.

Results

Of 316 screened, 213 were enrolled with 190 (89.2%) of these having a dilated bile duct, abnormal labs, iAP, or some combination. By imputation, an average of 122/213 (57.4% [95%CI 50.4-64.4]) improved; response rate was similar for those with complete follow-up (99/161, 61.5%, [54.0-69.0]); of these, 118 (73.3%) improved by PGIC alone. Duct size, elevated labs, and patient characteristics were not associated with response. AP occurred in 37/213 (17.4%) at a median of 6 months post-ERCP and was more likely in those with a history of AP (30.9 vs. 2.9%, p<0.0001).

Conclusion

Nearly 60% of patients undergoing ERCP for suspected SOD improve, although the contribution of a placebo response is unknown. Contrary to prevailing belief, duct size and labs are poor response predictors. AP recurrence was common and like observations from prior non-intervention cohorts, suggesting no benefit of sphincterotomy in mitigating future AP episodes.Key Messages: WHAT IS ALREADY KNOWN ON THIS TOPIC: It is not clear if the sphincter of Oddi can cause abdominal pain (Functional Biliary Sphincter of Oddi Disorder) and idiopathic acute pancreatitis (Functional Pancreatic Sphincter of Oddi Disorder), and whether ERCP with sphincterotomy can ameliorate abdominal pain or pancreatitis.WHAT THIS STUDY ADDS: Using multiple patient-reported outcome measures, most patients with suspected sphincter of Oddi disorder improve after ERCP with sphincterotomy.Duct size, elevated pancreatobiliary labs, and baseline patient characteristics are not independently associated with response.There is a high rate of recurrent acute pancreatitis within 12 months of sphincterotomy in those with a history of idiopathic acute pancreatitis.HOW THIS STUDY MIGHT AFFECT RESEARCH, PRACTICE, OR POLICY: Since a discrete population with a high (> 80-90%) response rate to sphincterotomy for suspected pancreatobiliary pain could not be identified, there is a need for additional observational and interventional studies that include phenotyping of patients using novel imaging or biochemical biomarkers.There remains a pressing need for quantitative nociceptive biomarkers to distinguish pancreatobiliary pain from other causes of abdominal pain or central sensitization.Discovery of blood-, bile-, or imaging-based biomarkers for occult microlithiasis and pancreatitis may be helpful in predicting who is likely to benefit from sphincterotomy.

Biliary Duct Dilatation: AJR Expert Panel Narrative Review

Biliary duct dilatation is a common incidental finding in practice, but it is unlikely to indicate biliary obstruction in the absence of clinical symptoms or elevated levels on liver function tests (LFTs). However, the clinical presentation may be nonspecific, and LFTs may either be unavailable or difficult to interpret. The goal of this AJR Expert Panel Narrative Review is to highlight a series of topics fundamental to the management of biliary duct dilatation, providing consensus recommendations in a question-and-answer format. We start by covering a basic approach to interpreting LFT results, the strengths and weaknesses of the biliary imaging modalities, and how and where to measure the extrahepatic bile duct. Next, we define the criteria for biliary duct dilatation, including patients with prior cholecystectomy and advanced age, and discuss when and whether biliary duct dilatation can be attributed to papillary stenosis or sphincter of Oddi dysfunction. Subsequently, we discuss two conditions in which the duct is pathologically dilated but not obstructed: congenital cystic dilatation (i.e., choledochal cyst) and intraductal papillary neoplasm of the bile duct. Finally, we provide guidance regarding when to recommend obtaining additional imaging or testing, such as endoscopic ultrasound or ERCP, and include a discussion of future directions in biliary imaging.

Biliary Anatomy 2.0 Quiz: Test Your Knowledge

Anatomy has remained an interest of physicians throughout the ages. The biliary tract spans from the liver to the hepatoduodenal mesentery, pancreas, and into the duodenum. Therefore, it is important for not only hepatobiliary surgeons but also general gastrointestinal surgeons, gastroenterologists, radiologists, and pathologists to be familiar with biliary anatomy and its variants. While surgery for hilar cholangiocarcinoma is one of the most challenging procedures, cholecystectomy is one of the most common procedures done from the beginning of surgical training. We hope that by answering the following questions, you will gain a comprehensive understanding of biliary anatomy and a greater appreciation for it.

Addiction and the Risk of Common Bile Duct Stones: A 4-Year Retrospective Population-Based Study in Mashhad, Iran

BACKGROUND

As a common digestive disorder, choledocholithiasis can have serious consequences, including death. Given that opioids have been shown to contribute to the spasm of Oddi's sphincter, which results in biliary stasis in the common bile duct (CBD), it is likely that opioids can also raise the prevalence of choledocholithiasis. In this regard, this study aimed to investigate how common opium addiction was among choledocholithiasis patients in Mashhad, Iran.

METHODS

The current retrospective observational study was conducted on 599 patients with choledocholithiasis who underwent endoscopic retrograde cholangiopancreatography (ERCP), utilizing information gathered at the Ghaem hospital in Mashhad, Iran, between 2011 and 2015. Patient data were collected from files and records using certain criteria such as gender, opium addiction, hepatic enzymes (AST, ALT, ALP), plasma levels of total bilirubin, and direct bilirubin. The size of the CBD stones as well as the correlation between the gallbladder and CBD stones were calculated.

FINDINGS

From among 599 patients included, 345 (57.6%) were female and 254 (42.4%) were male. Moreover, 195 patients (32.2%) had opiate addictions. The size of the CBD stone was correlated with the patient's age (r=0.17, P=0.001). The average stone measured 12.22±3.32 mm. There were notable differences in the mean size of the CBD stone (P<0.001) between addicted and non-addicted cases; specifically, the mean CBD stone size in addicted cases was 12.715.13 mm while it was 12.34.33 mm in non-addicted cases.

CONCLUSION

This study showed patients with CBD stones have a higher rate of opium addiction compared to the general population, indicating a possible link between the two conditions.

Utilizing CT to identify clinically significant biliary dilatation in symptomatic post-cholecystectomy patients: when should we be worried?

PURPOSE

To determine a reliable threshold common duct diameter on CT, in combination with other ancillary CT and clinical parameters, at which the likelihood of pathology requiring further imaging or intervention is increased in post-cholecystectomy patients.

METHODS

In this IRB approved retrospective study, two attending radiologists independently reviewed CT imaging for 118 post-cholecystectomy patients, who were subsequently evaluated with MRCP, ERCP, or EUS, prompted by findings on the CT and clinical status. Measurements of the common duct (CD) were obtained at the porta hepatis, distal duct, and point of maximal dilation on axial and coronal CT scans. Patients were grouped by whether they required intervention after follow-up imaging. Pertinent baseline lab values and patient demographics were reviewed.

RESULTS

Of the 118 post-cholecystectomy patients, 38 patients (31%) required intervention, and 80 patients (69%) did not require intervention after follow-up imaging. For both readers, axial and coronal CD diameters were significantly higher in the 'intervention required' vs 'no intervention' groups at all locations (p value < 0.05). There was good to excellent inter-reader agreement at all locations (ICC 0.68-0.92). Pertinent baseline lab values including AST (p = 0.043), ALT (p = 0.001), alkaline phosphatase (p = 0.0001), direct bilirubin (p = 0.011), total bilirubin (p = 0.028), and WBC (p = 0.043) were significantly higher in the 'intervention required' group. CD thresholds of 8 mm yielded the highest sensitivities (76-95%), and CD thresholds of 12 mm yielded the highest specificities (65-78%). CD combined with bilirubin levels increased sensitivity and specificity, compared to using either feature alone.

CONCLUSION

Dilated CD on CT combined with bilirubin levels increases the sensitivity and specificity for identifying patients needing intervention. We recommend that a post-cholecystectomy patient who presents with a CD diameter > 10 mm on CT and elevated bilirubin levels should undergo further clinical and imaging follow-up.

The role of endoscopic ultrasound in evaluating patients with bile duct dilation of unclear etiology

OBJECTIVE

Bile duct dilation (BDD) of unclear etiology is a common indication for further imaging via endoscopic ultrasound (EUS). We aimed to assess the yield of EUS in determining BDD etiology in patients with prior non-diagnostic imaging studies.

METHODS

A retrospective chart review was performed at a single, tertiary-care university hospital for patients referred for EUS for BDD with or without pancreatic duct dilation (PDD). EUS-guided fine needle aspiration (FNA) was performed if a focal lesion was identified. Cases with an etiology of BDD diagnosed or strongly suggested by prior imaging were excluded. EUS findings believed to represent a structural cause for BDD included a wide range of pancreaticobiliary and luminal pathology as well as patients' clinical factors.

RESULTS

In total, 307 patients were identified. Findings to explain BDD were found by EUS in 213 patients for a diagnostic yield of 69.4%. Patients with jaundice were significantly more likely to receive a diagnosis by EUS than those without (78.8% vs 55.3%, P < 0.01). Notably, 8.1% of patients with normal liver function test (LFT) had a EUS-diagnosed malignancy. Patients' age, narcotic use, concurrent PDD and prior cholecystectomy did not appear to influence the EUS yield.

CONCLUSIONS

EUS continues to play a substantial role in evaluating BDD of unclear etiology, most notably in patients with jaundice. In addition, given that 8.1% of asymptomatic patients without jaundice or abnormal LFT had malignancy diagnosed on EUS, the use of EUS for BDD of unclear etiology remains warranted.