The Diagnostic Value of Endoscopic Ultrasonography for Common Bile Duct Dilatation without Identifiable Etiology Detected from Cross-Sectional Imaging

Diagnostic yield of endoscopic ultrasound in dilated common bile duct with non-diagnostic cross-sectional imaging

BACKGROUND

Biliary dilatation without obvious etiology on cross sectional imaging warrants further investigation. This study aimed to assess yield of endoscopic ultrasound in providing etiologic diagnosis in such situation.

METHODS

Prospective cohort of consecutive patients with biliary dilatation & non diagnostic computed tomography (CT) and /or magnetic resonance imaging (MRI) underwent endoscopic ultrasound (EUS) with/without fine needle aspiration cytology (FNAC) and were followed clinically, biochemically with/without radiology for up to six months. The findings of EUS were corroborated with histopathology of surgical specimens and endoscopic retrograde cholangiography (ERCP) findings in relevant cases.

RESULTS

Median age of 121 patients completing follow up was 55 years. 98.2% patients were symptomatic and median common bile duct (CBD) diameter was 13 mm. EUS was able to identify lesions attributable for biliary dilatation in (67 out of 121) 55.4% cases with ampullary neoplasm being the commonest (29 out of 67 i.e. 43%). Multivariate logistic regression analysis identified jaundice as the predictor of positive diagnosis on EUS, of finding ampullary lesion and pancreatic lesion on EUS. EUS had sensitivity, specificity, positive predictive value and diagnostic accuracy of 95.65%, 94.23%, 95.65% and 95.04% respectively in providing etiologic diagnosis. Threshold value for baseline bilirubin of 10 mg%, for baseline CA 19.9 of 225 u/L and for largest CBD diameter of 16 mm were determined to have specificity of 98%, 95%, 92.5% respectively of finding a positive diagnosis on EUS.

CONCLUSION

EUS provides considerable diagnostic yield with high accuracy in biliary dilatation when cross sectional imaging fails to provide etiologic diagnosis.

The Endoscopic Retrograde Cholangiopancreatography and Endoscopic Ultrasound Connection: Unity Is Strength, or the Endoscopic Ultrasonography Retrograde Cholangiopancreatography Concept

Endoscopic ultrasound (EUS) and endoscopic retrograde cholangiopancreatography (ERCP) are both crucial for the endoscopic management of biliopancreatic diseases: the combination of their diagnostic and therapeutic potential is useful in many clinical scenarios, such as indeterminate biliary stenosis, biliary stones, chronic pancreatitis and biliary and pancreatic malignancies. This natural and evident convergence between EUS and ERCP, which by 2006 we were calling the "Endoscopic ultrasonography retrograde colangiopancreatography (EURCP) concept", has become a hot topic in the last years, together with the implementation of the therapeutic possibilities of EUS (from EUS-guided necrosectomy to gastro-entero anastomoses) and with the return of ERCP to its original diagnostic purpose thanks to ancillary techniques (extraductal ultrasound (EDUS), intraductal ultrasound (IDUS), cholangiopancreatoscopy with biopsies and probe-based confocal laser endomicroscopy (pCLE)). In this literary review, we retraced the recent history of EUS and ERCP, reported examples of the clinical applicability of the EURCP concept and explored the option of performing the two procedures in only one endoscopic session, with its positive implications for the patient, the endoscopist and the health care system. In the last few years, we also evaluated the possibility of combining EUS and ERCP into a single endoscopic instrument in a single step, but certain obstacles surrounding this approach remain.

Comparing the efficacy of EUS versus MRCP with ERCP as gold standard in patients presenting with partial biliary obstruction - finding a better diagnostic tool

Objective

To evaluate the diagnostic accuracy of different imaging modalities in patients with partial biliary obstruction with no obvious aetiology on initial imaging.

Methods

This is a prospective single-centre cohort study carried out at Pak Emirates Military Hospital, Rawalpindi from June 2019 to June 2021 with non-probability consecutive sampling. Patients with ages 16 to 75 years, presenting with partial biliary obstruction and undetermined aetiology on initial imaging (TUS and MRCP) were enrolled. EUS was performed for each of these patients and the case was regarded as "true positive" or "true negative" if the findings of imaging modality correlated to those of ERCP. ROC curve, sensitivity, specificity, PPV, NPV and AUC (with 95% confidence interval) were drawn for all the diagnostic tools using SPSS V. 21.

Results

A total of 65 patients were enrolled over a period of two years with male to female ratio of 1.4:1. Forty-four patients had an intermediate risk of choledocholithiasis upon preliminary evaluation whereas, 48(74%) of the participants had CBD calculi or sludge confirmed upon subsequent ERCP. Trans-abdominal ultrasound showed the lowest sensitivity (29.2%), specificity (85%), NPV 12% and PPV 93% for diagnosing CBD calculi. This was followed by MRCP with a sensitivity of 37.5%, specificity of 100%, NPV of 36.2% and PPV of 100%. EUS showed the maximum diagnostic accuracy with AUC of 1.0 and a 100% sensitivity and specificity when compared with ERCP as gold standard.

Conclusion

EUS is superior to MRCP in terms of diagnostic accuracy as minimally invasive diagnostic tool and EUS superiority is particularly relevant in patients with intermediate risk of choledocholithiasis.

Role of endoscopic ultrasound in the evaluation of unexplained extrahepatic bile duct dilatation

OBJECTIVE

This study was performed to assess the diagnostic performance of endoscopic ultrasonography (EUS) in patients with extrahepatic bile duct (EBD) dilatation and develop a novel model incorporating EUS-based signature with clinical parameters for distinguishing the malignant dilation of EBD.

METHODS

The EUS data and clinical parameters of the patients were collected and analyzed retrospectively. First, we evaluated the diagnostic performance of EUS in detecting the cause of EBD dilatation. Then, we performed univariate and multivariate binary logistic regression analyses based on clinical and EUS features. Finally, a nomogram was established to aid in distinguishing between malignant dilation and noncalculous benign dilatation of EBD in patients.

RESULTS

A total of 184 patients were enrolled. For the diagnosis of malignant dilation, EUS achieved an accuracy of 90.76%, sensitivity of 85.96%, and specificity of 92.91%. For the diagnosis of calculous dilation, EUS achieved an accuracy of 100%, sensitivity of 100%, and specificity of 100%. For the diagnosis of noncalculous benign dilatation, EUS achieved an accuracy of 90.76%, sensitivity of 90.90%, and specificity of 90.58%. Multivariable logistic regression analyses indicated that abnormal liver function test, elevated tumor markers, and EUS findings were the well-diagnostic factors of malignant EBD dilation. The nomogram established by these factors showed good calibration and discrimination.

CONCLUSION

EUS is a useful examinational modality in the work-up of EBD dilatation. In combination with abnormal liver function test and elevated tumor markers, EUS may provide additional information for the detection of malignant dilation of EBD and should be further investigated.