Wire-guided intraductal US: an adjunct to ERCP in the management of bile duct stones

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.

Advanced Imaging of the Biliary System and Pancreas

Despite advances in noninvasive techniques for imaging the pancreaticobiliary system, several disease processes including indeterminate biliary strictures as well as neuroendocrine tumors, inflammatory pseudotumors, and complex cysts of the pancreas remain difficult to characterize. New endoscopic imaging technologies have emerged to address these challenges. Cholangioscopy and intraductal ultrasound (IDUS) are powerful tools to characterize subtle biliary concretions and strictures. Confocal Laser Endomicroscopy (CLE) and Optical Coherence Tomography (OCT) are emerging approaches for the most difficult biliary lesions. Contrast harmonic endoscopic ultrasound (CH-EUS), elastography, and 3D-EUS are improving the approach to subtle pancreatic lesions, particularly in the context of indeterminate tissue sampling. Pancreatoscopy, pancreatic IDUS, and intracystic CLE hold promise to further improve the assessment of pancreatic cysts. We aim to comprehensively review the emerging clinical evidence for these innovative endoscopic imaging techniques.

Effect of stent placement on stone recurrence and post-procedural cholangitis after endoscopic removal of common bile duct stones

BACKGROUND/AIMS

After endoscopic treatment of common bile duct (CBD) stones, recurrence of choledocholithiasis due to small stone fragments and post-endoscopic retrograde cholangiopancreatography (post-ERCP) cholangitis can occur. We determined the effect of biliary stenting after removal of CBD stones on the recurrence of CBD stones and the incidence of post-ERCP cholangitis.

METHODS

We performed a retrospective single-center study involving 483 patients who underwent ERCP for the removal of CBD stones. The patients were classified into two groups according to their biliary stenting status. The primary outcome was the rate of CBD stone recurrence and the secondary outcome was the incidence of post-ERCP cholangitis.

RESULTS

Among the 483 patients, 219 and 264 did and did not receive a biliary stent after CBD stone removal, respectively. The incidence of stone recurrence was 15.5% and 7.6% in the non-stenting and stenting groups (p = 0.006), respectively, while the incidence of post-ERCP cholangitis was 4.6% and 2.7% (p = 0.256). In a multivariate analysis, biliary stenting significantly reduced the stone recurrence rate (odds ratio, 0.30; p = 0.004).

CONCLUSION

Biliary stenting after the removal of CBD stones reduces the stone recurrence rate and assisted recovery. For patients with large and multiple stones who undergo lithotripsy, preventive biliary stent insertion can reduce the rate of stone recurrence.

Pancreatic duct guidewire placement for biliary cannulation as a risk factor for stone residue after endoscopic transpapillary stone removal

Background

Recent improvements in stone extraction implements and apparatus have lessened the complexity of the endoscopic bile duct stone treatment. However, despite confirmation of complete removal, cases of residual stones have been reported, which can result in recurrent biliary symptoms, cholangitis, and pancreatitis and considerably increase cost given the need for repeat imaging and/or procedures. To date, risk factors for residual bile duct stones following endoscopic retrograde cholangiopancreatography (ERCP) extraction have not been thoroughly evaluated. This study retrospectively investigated the incidence and risk factors of residual bile duct stones following extraction via ERCP.

Methods

We retrospectively reviewed all ERCP cases that underwent endoscopic bile duct stone extraction between April 2014 and March 2019. A total of 505 patients were enrolled and evaluated for the incidence and risk factors of residual bile duct stones after ERCP.

Results

The rate of residual stones was 4.8% (24/505). Residual stones were detected by computed tomography (12/24) or magnetic resonance cholangiopancreatography (12/24). In univariate analyses, a large number of stones (P = 0.01), long procedure time (P = 0.005), and performance of the pancreatic duct guidewire placement method (P-GW) for selective bile duct cannulation (P = 0.01) were the factors involved in residual stones. In multiple logistic regression analysis, performing P-GW was retained as the only independent factor of residual stones (adjusted odds ratio, 3.44; 95% CI, 1.19–9.88; P = 0.02).

Conclusions

When removing bile duct stones with a pancreatic guidewire in place, paying attention to residual stones is necessary.

The Value of Contrast-Enhanced Ultrasound-Guided Contrast Injection via the Endoscopic Nasobiliary Drainage Duct in Diagnosing Residual Common Bile Duct Stones

Objectives

To investigate the diagnostic value of contrast-enhanced ultrasound- (CEUS-) guided contrast injection via an endoscopic nasobiliary drainage (ENBD) tube on the evaluation for residual stones in common bile duct (CBD).

Methods

116 patients with CBD stones were treated by endoscopic retrograde cholangiopancreatography and duodenoscopic sphincterotomy incision surgery and ENBD. The US group consisted of 54 patients who underwent US-guided saline injection via the ENBD tube to evaluate for residual CBD stones. The CEUS group consisted of 62 patients who underwent CEUS-guided contrast injection via the ENBD tube to evaluate for residual CBD stones. The length and width of CBD and the detection rate of residual stones before and after NS injection were compared.

Results

In both the US group and the CEUS group, the rate of complete demonstration and the average length and width of CBD before and after injection of NS were all increased significantly. In the US group, 6 patients had verified residual stones, 1 of which was detected by conventional US (detection rate, 1/6), 5 of which were detected by saline injection ultrasound (detection rate, 5/6), and 4 of which were detected by ENBD cholangiography (detection rate, 4/6). There was 1 false positive result on saline injection US and 2 false positives on ENBD cholangiography. In the CEUS group, 6 patients had verified residual stones, none of which were detected by conventional US (detection rate, 0/6), all of which were detected by saline injection CEUS (detection rate, 6/6), and 4 of which were detected by ENBD cholangiography (detection rate, 4/6). There was 1 false positive result on ENBD cholangiography.

Conclusions

CEUS-guided contrast injection via an ENBD tube helps to provide clear observation of residual stones in the CBD after ERCP with EST and provides comprehensive information for follow-up.

Efficacy of endoscopic ultrasound after removal of common bile duct stone

Objective: Endoscopic retrograde cholangiopancreatography (ERCP) is a standard procedure for choledocholithiasis. Nonetheless, the recurrence rate remains quite high. This study aimed to investigate the prevalence and related factors of remnant biliary stone or sludge using endoscopic ultrasound (EUS) after the removal of common bile duct (CBD) stone and to evaluate the long-term clinical outcomes. Methods: A prospective study enrolling a consecutive series of patients who underwent ERCP for CBD stone removal was performed between June 2014 and November 2015. Following confirmation of complete CBD stone removal by the operator, EUS was performed to determine whether biliary stone or sludge remained. Patients underwent cholecystectomy if a gallstone was identified and were subsequently followed up at a regular interval of 3-6 months. We investigated whether symptomatic recurrence would occur. Results: A total of 130 patients were enrolled. The presence of remnant biliary stone or sludge after ERCP was confirmed in 36.9% (48/130) of patients. Acute angulation of the distal CBD was the sole factor associated with remnant biliary stone or sludge (p < .01). During the follow-up period, the overall recurrence rate was 17.7% (23/130). Recurrent symptomatic choledocholithiasis was predicted by remnant biliary sludge and large CBD diameter in multivariate analysis. Conclusions: Acute angulation of the distal CBD was associated with remnant biliary stone or sludge after ERCP. Remnant biliary sludge on EUS and large CBD diameter were strong predictors of symptomatic recurrence. EUS evaluation following CBD stone removal could be an effective strategy in the treatment of choledocholithiasis.

Clinical value of DPOC for detecting and removing residual common bile duct stones (video)

Background

This study aims to evaluate the efficacy and safety of detecting and removing residual common bile duct stones (CBDS) using direct peroralcholangioscopy (DPOC) after performing endoscopic retrograde cholangiopancreatography (ERCP) for stone retrieval.

Methods

From January 5, 2017 to December 27, 2017, a total of 164 cases of choledocholithiasis were treated by ERCP for stone retrieval. According to the inclusion and exclusion criteria, the remaining 79 cases (39 males; mean age: 63.3 years old, range: 52–79 years old) were enrolled in the present study. The maximum transverse stone diameter was 6–15 mm (12.7 ± 4.2 mm), as determined by ERCP. Furthermore, there were 57 cases of multiple stones (number of stones: two in 41 cases, three in nine cases, and ≥ 4 in seven cases), 13 cases of post-mechanical lithotripsy, and nine cases of broken stones.

Results

The overall success rate of DPOC was 94.9% (75/79). Furthermore, 18.7%(14/75) of cases were directly inserted, 72%(54/75) of cases required guide wire assistance, and 9.3%(7/75) of cases were successfully inserted with overtube assistance. The average insertion time was 7–17 min (4.9 ± 2.9 min). Residual stones were detected in 19 cases (25.3%), and all of which were < 5 mm in diameter. Moreover, five cases of formed stones were removed by basket and balloon catheter, while the remaining cases were cleaned after irrigation and suction. There were no serious complications.

Conclusion

DPOC is safe and effective for both the detection and removal of residual CBDS after conventional ERCP.

Electronic supplementary material

The online version of this article (10.1186/s12876-019-1045-6) contains supplementary material, which is available to authorized users.

Advances in Endoscopic Imaging of the Biliary Tree

Direct endoscopic imaging of the biliary tree is increasingly performed by endoscopists since the introduction of digital single-operator cholangioscopy. In parallel, there have been several advances to overcome the challenges associated with direct peroral cholangioscopy with development of multibending cholangioscopes and new devices to enable direct placement of an endoscope into the biliary tree without a supporting duodenoscope. The indications for cholangioscopy are also evolving with newer indications, such as intraductal lithotripsy, foreign body (mostly stent) removal, guide wire cannulation of specific ducts, photodynamic therapy for cholangiocarcinoma, and performance of fluoroscopy-free cholangiography. There has also been progress in image enhancement during cholangioscopy and additional imaging techniques, such as intraductal ultrasound, confocal laser endomicroscopy, and optical coherence tomography.

The added value of tomosynthesis in endoscopic retrograde cholangiography with radiography for the detection of choledocholithiasis

OBJECTIVE

The diagnostic performance of endoscopic retrograde cholangiography (ERC) with radiography is imperfect. We assessed the value of adding tomosynthesis to ERC with radiography for the detection of choledocholithiasis.

METHODS

This study included 102 consecutive patients (choledocholithiasis/non-choledocholithiasis, n = 57/45), who underwent both radiography and tomosynthesis for ERC in the same examination and were not diagnosed with malignancy. The reference standard for the existence of choledocholithiasis was confirmed by endoscopic stone extraction during ERC, intraoperative cholangiography, or follow up with magnetic resonance cholangiopancreatography (n = 78, 11, and 13, respectively). A gastroenterologist and a radiologist independently evaluated the radiographs and the combination of tomosynthesis and radiographic images in a blinded and randomised manner. Receiver operating characteristic analysis was used for statistical analysis.

RESULTS

The areas under the receiver operating characteristic curve for combined tomosynthesis and radiography were significantly higher than those for radiography alone for both readers: Reader 1/Reader 2, 0.929/0.956 [95% confidence interval (CI), 0.861-0.965/0.890-0.983) vs 0.803/0.769 (95% confidence interval, 0.707-0.873/0.668-0.846), respectively (p = 0.0047/< 0.0001).

CONCLUSION

Adding tomosynthesis to radiography improved the diagnostic performance of ERC for detection of choledocholithiasis. Advances in knowledge: Adding tomosynthesis to radiography improves detection of choledocholithiasis and tomosynthesis images can be obtained easily after radiographs and repeated immediately.

Miniprobe Endoscopic Sonography for Gastrointestinal Tract Assessment: A Case Series of 1451 Procedures

Conventional endoscopic sonography has allowed precise diagnostics without disturbances, and miniprobes can be easily introduced through the biopsy channel of the endoscope. Miniprobe endoscopic sonography has many benefits compared with conventional endoscopic sonography. Although there are well-known indications for miniprobe endoscopic sonography in endoscopic digestive tract assessment, there is still a need for this method to be widely spread among physicians and commonly used by most endoscopists. The aim of this series was to describe a multicenter retrospective experience with 1451 procedures using miniprobes, presenting examples and the applicability and usefulness of this technology in the daily activities of an endoscopy department.

Role of Balloon-Sheathed Intraductal Ultrasonography for Patients with Extensive Pneumobilia

Intraductal ultrasonography (IDUS) is one of the most useful diagnostic tools for various extrahepatic biliary diseases. However, conventional IDUS has some limitations in providing accurate cross-sectional imaging of the bile duct in patients with extensive pneumobilia. Using a balloon-sheathed catheter, the US system (balloon-sheathed IDUS) can overcome these limitations. Sixteen patients underwent balloon-sheathed IDUS during endoscopic retrograde cholangiography. The balloon-sheathed IDUS was inserted via a transpapillary route when visualization of the bile duct with conventional IDUS was distorted by extensive pneumobilia. The patient group had a mean age of 65.5 years, and 56.3% (9/16) were male. The balloon-sheathed IDUS permitted successful visualization of the bile duct in all patients, regardless of the extent of pneumobilia. Using this system, remnant common bile duct stones were detected in five patients (31.3%), and cholangiocarcinoma was detected in one patient (6.3%). The balloon-sheath IDUS aided in stone sweeping. No significant complications, including bleeding, perforation, or pancreatitis, occurred in any of the patients. The balloon-sheathed catheter US system was useful and safe for biliary IDUS in patients with extensive pneumobilia.

Echoendoscopes

Advances in echoendoscopes and their processors have significantly expanded the role of EUS and its clinical applications.The diagnostic and therapeutic capabilities of EUS continue to evolve and improve. EUS has made a large impact on patient care but comes with significant startup and maintenance costs. As improved technology continues to enhance image resolution while decreasing the size of EUS processors, use of endosonography will become more widespread. EUS will continue to be a vital part of patient care and complement currently available cross-sectional imaging.

Clinical usefulness of intraductal ultrasonography for the management of acute biliary pancreatitis

BACKGROUND AND AIM

Identifying a bile duct (BD) stone in patients with acute biliary pancreatitis (ABP) is important for the management and prevention of recurrent attack of pancreatitis. However, small BD stones may not be detected on endoscopic retrograde cholangiopancreatography (ERCP). The aim of this study was to prospectively evaluate the usefulness of intraductal ultrasonography (IDUS) in patients suspected to have ABP but with no evidence of choledocholithiasis on ERCP.

METHODS

A total 92 patients suspected with ABP without evidence of BD stones on imaging studies including ERCP were enrolled. Wire-guided IDUS was performed during ERCP in all patients. Stones or sludge detected by IDUS were confirmed after endoscopic sphincterotomy (EST) and extraction. If IDUS finding was negative, then we swept the BD with a balloon catheter and/or basket without EST. After endoscopic management, comparison between IDUS and endoscopic finding was carried out to determine the diagnostic accuracy of IDUS.

RESULTS

Among the 92 patients, IDUS revealed BD stones in 33 (35.9%). All 33 patients' stones were confirmed by endoscopic visualization after EST and BD exploration. During the mean follow up of 24 months, recurrent pancreatitis did not occur in 90 of 92 patients (97.9%) with ABP after endoscopic treatment according to the IDUS findings.

CONCLUSIONS

IDUS improves diagnostic accuracy for the detection of clinically occult BD stones in patients suspicious ABP. IDUS-guided endoscopic management for patients with ABP can avoid unnecessary EST and help prevent recurrent pancreatitis.

Intraductal ultrasonographic anatomy of biliary varices in patients with portal hypertension

BACKGROUND AND OBJECTIVES

The term, portal biliopathy, denotes various biliary abnormalities, such as stenosis and/or dilatation of the bile duct, in patients with portal hypertension. These vascular abnormalities sometimes bring on an obstructive jaundice, but they are not clear which vessels participated in obstructive jaundice. The aim of present study was clear the bile ductal changes in patients with portal hypertension in hopes of establishing a therapeutic strategy for obstructive jaundice caused by biliary varices.

MATERIALS AND METHODS

Three hundred and thirty-seven patients who underwent intraductal ultrasound (IDUS) during endoscopic retrograde cholangiography for biliary abnormalities were enrolled. Portal biliopathy was analyzed using IDUS.

RESULTS

Biliary varices were identified in 11 (2.7%) patients. IDUS revealed biliary varices as multiple, hypoechoic features surrounding the bile duct wall. These varices could be categorized into one of two groups according to their location in the sectional image of bile duct: epicholedochal and paracholedochal. Epicholedochal varices were identified in all patients, but paracholedochal varices were observed only in patients with extrahepatic portal obstruction.

CONCLUSION

IDUS was useful to characterize the anatomy of portal biliopathy in detail.

Usefulness of intraductal ultrasonography in icteric patients with highly suspected choledocholithiasis showing normal endoscopic retrograde cholangiopancreatography

BACKGROUND

Choledocholithiasis is one of the causes of jaundice and may require urgent treatment. Endoscopic retrograde cholangiopancreatography (ERCP) has been the primary management strategy for choledocholithiasis. However, small stones can be overlooked during ERCP.

AIM

The aim of this study was to evaluate the accuracy of intraductal ultrasonography (IDUS) for detecting choledocholithiasis in icteric patients with highly suspected common bile duct (CBD) stones without definite stone diagnosis on ERCP.

METHODS

Ninety-five icteric (bilirubin ≥ 3 mg/dL) patients who underwent ERCP for highly suspected choledocholithiasis without definite filling defects on cholangiography were prospectively enrolled in the present study. We evaluated the bile duct using IDUS for the presence of stones or sludge. Reference standard for choledocholithiasis was endoscopic extraction of stone or sludge.

RESULT

Bile duct stones were detected with IDUS in 31 of 95 patients (32.6%). IDUS findings were confirmed by endoscopic stone extraction in all patients. The mean diameter of CBD stones detected by IDUS was 2.9 mm (range 1-7 mm). IDUS revealed biliary sludge in 24 patients (25.2%) which was confirmed by sludge extraction in 21 patients (87.5%). In dilated CBD, detection rate of bile duct stone/sludge based on IDUS was significantly higher than in non-dilated CBD (p = 0.004).

CONCLUSION

IDUS is useful for the detection of occult CBD stone on ERCP in icteric patients with highly suspected CBD stones.

Residual common bile duct stones on direct peroral cholangioscopy using ultraslim endoscope

AIM: To detect and manage residual common bile duct (CBD) stones using ultraslim endoscopic peroral cholangioscopy (POC) after a negative balloon-occluded cholangiography.

METHODS: From March 2011 to December 2011, a cohort of 22 patients with CBD stones who underwent both endoscopic retrograde cholangiography (ERC) and direct POC were prospectively enrolled in this study. Those patients who were younger than 20 years of age, pregnant, critically ill, or unable to provide informed consent for direct POC, as well as those with concomitant gallbladder stones or CBD with diameters less than 10 mm were excluded. Direct POC using an ultraslim endoscope with an overtube balloon-assisted technique was carried out immediately after a negative balloon-occluded cholangiography was obtained.

RESULTS: The ultraslim endoscope was able to be advanced to the hepatic hilum or the intrahepatic bile duct (IHD) in 8 patients (36.4%), to the extrahepatic bile duct where the hilum could be visualized in 10 patients (45.5%), and to the distal CBD where the hilum could not be visualized in 4 patients (18.2%). The procedure time of the diagnostic POC was 8.2 ± 2.9 min (range, 5-18 min). Residual CBD stones were found in 5 (22.7%) of the patients. There was one residual stone each in 3 of the patients, three in 1 patient, and more than five in 1 patient. The diameter of the residual stones ranged from 2-5 mm. In 2 of the patients, the residual stones were successfully extracted using either a retrieval balloon catheter (n = 1) or a basket catheter (n = 1) under direct endoscopic control. In the remaining 3 patients, the residual stones were removed using an irrigation and suction method under direct endoscopic visualization. There were no serious procedure-related complications, such as bleeding, pancreatitis, biliary tract infection, or perforation, in this study.

CONCLUSION: Direct POC using an ultraslim endoscope appears to be a useful tool for both detecting and treating residual CBD stones after conventional ERC.

Advances in the investigation of obstructive jaundice

The causes of obstructive jaundice are varied, and timely, accurate methods of investigation are essential to avoid the development of complications. Imaging, invasive or non-invasive, should be carefully selected depending on the suspected underlying pathology in order to determine the degree and level of obstruction along with tissue acquisition and staging where relevant. Several imaging techniques will also allow subsequent therapeutic interventions to be carried out. This article reviews advances in the investigation of obstructive jaundice, highlighting recent developments, many of which at present remain restricted to large centres of expertise, but are likely to become more widespread in use as research progresses and local experience continues to improve.

The role of intraductal US in the management of idiopathic recurrent pancreatitis without a definite cause on ERCP

BACKGROUND

The cause of pancreatitis is unknown in as many as 30% of cases of recurrent acute pancreatitis, even after ERCP.

OBJECTIVE

To investigate the role of intraductal US (IDUS) for managing idiopathic recurrent pancreatitis (IRP).

DESIGN

Prospective study.

SETTING

Tertiary referral hospital.

PATIENTS

Thirty-one patients with suspicious IRP with negative findings on ERCP.

INTERVENTIONS

IDUS during ERCP.

MAIN OUTCOME MEASUREMENTS

IDUS findings showing any possible cause of pancreatitis.

RESULTS

IDUS revealed small bile duct stones (≤3 mm) in 5 patients (16.1%) and sludge in 3 patients (9.7%). The detection rate for a bile duct stone and sludge was significantly higher in patients with a dilated CBD than a nondilated CBD on ERCP (71.4 vs 12.5%; P < .05). Recurrent pancreatitis did not develop in 7 of 8 patients with biliary stones or sludge after an endoscopic sphincterotomy (EST). Two patients (6.5%) demonstrated a small polypoid lesion on the distal end of the pancreatic duct. One patient underwent surgery for intra-ampullary cancer, and another one underwent EST without another attack of pancreatitis. Three patients (9.7%) showed evidence of chronic pancreatitis with small pancreatic stones and/or calcifications on IDUS.

LIMITATIONS

Small number of patients. IDUS results were not compared with those of conventional EUS. There was no reference standard for chronic pancreatitis as diagnosed by IDUS.

CONCLUSIONS

IDUS identified a possible cause of idiopathic recurrent pancreatitis in 42% of patients with negative findings on ERCP. The IDUS-guided approach combined with ERCP and EST may be useful for decreasing recurring attacks of pancreatitis.

Intraductal ultrasonography in the diagnosis of bile duct stones: when and whom?

BACKGROUND AND AIM

Biliary intraductal ultrasonography (IDUS) is highly sensitive in visualizing bile duct stones (BDS). Indications for IDUS, however, in cases of suspected BDS have not yet been established. The aim of the present study was to elucidate adequate indications for IDUS in cases that undergo endoscopic retrograde cholangiopancreatography (ERCP) due to suspected BDS.

METHODS

A total of 213 patients who were suspected of having BDS were included in this retrospective study. The patients were divided into two groups: Group A in which BDS was visualized by ERCP; and Group B in which BDS was demonstrated only by IDUS. Comparison between the groups was carried out.

RESULTS

ERCP successfully visualized BDS in 166 patients. Forty-seven patients underwent IDUS, which revealed BDS and biliary sludge in 12 and eight patients, respectively. The diameter of the largest stone was 13 ± 6 mm in Group A and 5 ± 1 mm in Group B (P < 0.001). The sensitivity, specificity, and accuracy of ERCP in the diagnosis of BDS were 93%, 100%, and 94%, respectively. The sensitivity was influenced by the size of BDS: 100% in cases of stones ≥ 8 mm in size, but 74% in those with stones < 8 mm. In cases with stones < 8 mm, the sensitivity was significantly affected by the bile duct diameter (≥ 12 mm vs < 12 mm, P < 0.05).

CONCLUSION

  When ERCP fails to visualize stones in patients with suspected BDS, IDUS is recommended, especially in those with a bile duct ≥ 12 mm in diameter.

Evaluation of residual bile duct stones by peroral cholangioscopy in comparison with balloon-cholangiography

We evaluated the usefulness of peroral cholangioscopy (POCS) for residual bile duct stones in patients with complete bile duct clearance confirmed by balloon-occluded cholangiography. A total of 108 patients with common bile duct stones who underwent POCS after extraction of stones via endoscopic sphincterotomy, resulting in complete bile duct extraction confirmed by balloon-occluded cholangiography, were retrospectively evaluated. For the treatment of difficult stones, stones were fragmented by mechanical lithotripsy (ML) or electrohydraulic lithotripsy (EHL). In 26 patients (24%), residual stones were detected with POCS in the lower bile duct. In patients with residual stones, large bile duct stones, juxtapapillary diverticulum, and use of ML or EHL were significantly related to residual stones (P < 0.05). Although a prospective study is necessary to clarify whether this procedure is appropriate in aspects of cost and benefits, POCS appears to be a useful diagnostic tool for confirming complete extraction of bile duct stones. POCS may be useful, particularly when lithotripsy using ML or EHL is performed and a large pneumobilia exists in the bile duct.

Are the echogenicities on intraductal ultrasonography really biliary microlithiasis?

BACKGROUND

Intraductal ultrasonography (IDUS) is a useful procedure for diagnosing microlithiasis in the bile duct but it is not easy to differentiate between tiny echogenicity and real microlithiasis. We compared the echogenicity seen on IDUS and the findings of bile microscopy (BM) of bile that was collected in the common bile duct (CBD) to determine whether the echogenicity seen on IDUS is real microlithiasis.

METHODS

This prospective study involved a total of 30 patients who experienced biliary pain (n = 11), acute cholecystitis (n = 11) or indeterminate pancreatitis (n = 8) without a filling defect or obstruction in the bile duct. IDUS was performed during endoscopic retrograde cholangiopancreatography (ERCP), followed by bile aspiration for BM. Endoscopic sphincterotomy (EST) was performed if definite echogenic materials were observed on IDUS.

RESULTS

Of the 30 patients, 23 (77%) had echogenic materials visible in the CBD on IDUS. Of these 23 patients, 13 (57%) were found to have biliary crystals by BM. The size of the echogenic materials was the only significant factor associated with BM positivity. Using the receiver operating curve, the optimal size of the echogenicity to differentiate real microlithiasis was 1.4 mm.

CONCLUSIONS

Optimal concordance between IDUS and BM was observed when the size of the microlithiasis was greater than 1.4 mm; under these conditions the sensitivity and specificity were 71% and 75%, respectively. This information may be useful when deciding whether to perform endoscopic sphincterotomy.

Intraductal ultrasonography (IDUS) for the diagnosis of biliopancreatic diseases

Intraductal ultrasonography (IDUS) is an imaging modality having unique characteristics and suitable for imaging of a narrow ductal cavity, its wall and the neighbouring structures. As IDUS uses high-frequency ultrasound (12-30MHz), its image quality is very high within approximately 2-cm range of radius. The bile duct and the pancreatic duct, therefore, are good targets for the assessment by IDUS. Biliopancreatic IDUS is mainly performed through the papilla of Vater in the same session as endoscopic retrograde cholangiopancreatography (ERCP). Biliary IDUS is possible through the percutaneous transhepatic route as well. Not many comparative studies on biliopancreatic IDUS have been published. Gallbladder IDUS as well as most pancreatic IDUS are still at the level of clinical research. Constant delineation of Oddi's sphincter with the improvement of instruments will expand the use of IDUS for the assessment of the papilla of Vater lesions.

Clinical application of intraductal ultrasound during endoscopic retrograde cholangiopancreatography

Intraductal ultrasound (IDUS) used during endoscopic retrograde cholangiopancreatography (ERCP) can facilitate reliable evaluation of biliary and pancreatic disorders. The smaller diameter, flexibility, and the image quality offered by IDUS devices makes them ideal for evaluating a variety of difficult biliary and pancreatic diseases, especially in undefined strictures, luminal filling defects, and ampullary neoplasms. This article examines the numerous possible roles for IDUS in the evaluation of biliary and pancreatic conditions, as well as in ampullary neoplasms. IDUS is a simple, easy to learn, and safe technique that should be considered an integral tool in the therapeutic endoscopist's armamentarium.

Endoscopic ultrasound in the evaluation of radiologic abnormalities of the liver and biliary tree

Gastroenterologists increasingly find themselves in the un-enviable position of having to choose the optimal radiographic test to visualize the biliary tree and the liver. This dilemma is compounded by the rapid evolution of the available technologies and their ever-increasing resolution capabilities. Endoscopic ultrasound (EUS) has shown itself to be equally capable of providing detailed imaging of the biliary tree and of surrounding structures; its potential for evaluating liver lesions is just now being realized. EUS-fine needle aspiration (FNA) may supplant some of the existing technologies as it offers a way to sample masses, strictures, lymph nodes, and now certain segments of the liver and periportal regions. This review takes an in-depth look at the role of EUS in evaluating bile duct dilatation, suspected choledocholithiasis, biliary strictures, and polyps and masses of the gallbladder. It also reviews the literature on the exciting and rapidly evolving role of EUS-FNA evaluation of occult, metastatic, and primary hepato-cellular malignancies, as well as periportal lesions. Technologies such as EUS elastography may completely obviate FNA of liver lesions.

Risk factors for recurrent bile duct stones after endoscopic papillary balloon dilation: long-term follow-up study

BACKGROUND

Little is known about the long-term results of endoscopic papillary balloon dilation (EPBD) for bile duct stones.

METHODS

Between 1995 and 2000, 204 patients with bile duct stones successfully underwent EPBD and stone removal. Complete stone clearance was confirmed using balloon cholangiography and intraductal ultrasonography (IDUS). Long-term outcomes of EPBD were investigated retrospectively in the year 2007, and risk factors for stone recurrence were multivariately analyzed.

RESULTS

Long-term information was available in 182 cases (89.2%), with a mean overall follow-up duration of 9.3 years. Late biliary complications occurred in 22 patients (12.1%), stone recurrence in 13 (7.1%), cholangitis in 10 (5.5%), cholecystitis in four, and gallstone pancreatitis in one. In 11 of 13 patients (84.6%), stone recurrence developed within 3 years after EPBD. All recurrent stones were bilirubinate. Multivariate analysis identified three risk factors for stone recurrence: dilated bile duct (>15 mm), previous cholecystectomy, and no confirmation of clean duct using IDUS.

CONCLUSION

Approximately 7% of patients develop stone recurrence after EPBD; however, retreatment with endoscopic retrograde cholangiopancreatography is effective. Careful follow up is necessary in patients with dilated bile duct or previous cholecystectomy. IDUS is useful for reducing stone recurrence after EPBD.

Choledocholithiasis, ascending cholangitis, and gallstone pancreatitis

Gallstone disease is encountered commonly in clinical practice. The diagnosis of biliary stones has become less problematic with current, less-invasive imaging methods. The relatively invasive endoscopic techniques should be reserved for therapy and not used for diagnosis. Acute cholangitis and gallstone pancreatitis are two major complications that require prompt recognition and timely intervention to limit morbidity and prevent mortality or recurrence. Appropriate noninvasive diagnostic studies, adequate monitoring/supportive care, and proper patient selection for invasive therapeutic procedures are elements of good clinical practice.

Applicative value of intraductal ultrasonography in the removal of calculus by endoscopic retrograde cholangiopancreatgraphy

AIM: To discuss the value of intraductal ultrasonography (IDUS) in removing calculus by endoscopic retrograde cholangiopan-creatography (ERCP).

METHODS: One hundred patients with suspected extrahepatic bile duct stones were included in this study. ERCP was performed first followed by IDUS through endoscopic working channel to detect extrahepatic bile duct; finally the substance in extrahepatic bile duct was proved by endoscopic sphincterotomy (EST) and stone extraction. For the patients whose calculus was removed by galet basket, IDUS was performed again.

RESULTS: Of the 100 patients, bile duct stones were found in 93 cases, and cancer embolus, floccule, gas and Mirrizzi syndrome were found in 1 case respectively. Three cases were found without stones. Stones of 37 cases were extracted by galet basket and retained stones were found in 3 cases after ERCP. By ERCP, ninety-two cases were diagnosed with bile duct stones, 3 cases suspected, and 5 cases without stones and the final result showed that 3 cases were misdiagnosed. So the accuracy and sensitivity of ERCP were 97% and 94.8% respectively. By IDUS, no misdiagnosis and missing diagnosis occurred. So the accuracy and sensitivity of IDUS in the diagnosis of extrahepatic bile duct stones were 100% and 100% respectively.

CONCLUSION: IDUS can compensate the visual error of ERCP on extrahepatic bile duct stones. IDUS is superior to ERCP in the diagnosis of extrahepatic bile duct stones, especially cholangiectasis and Mirrizzi syndrome. Besides, IDUS can prevent retained stones after ERCP.

Suspected choledocholithiasis: endoscopic ultrasound or magnetic resonance cholangio-pancreatography? A systematic review

There is a lack of consensus on the optimal noninvasive strategy for patients with suspected choledocholithiasis after a negative transabdominal ultrasound and/or computed tomography. A meta-analysis was conducted to compare the diagnostic ability of endoscopic ultrasound (EUS) and magnetic resonance cholangio-pancreatography (MRCP) in patients with suspected common bile duct (CBD) stones. A search, using the following terms 'MRCP', 'EUS' and 'Choledocholithiasis' in Pubmed and Cochrane Controlled Trials Register, was performed. Abstract books and reference list of review articles, as well as relevant studies, were also searched to complete our EUS versus MRCP for choledocholithiasis comparison studies database. The analysis demonstrated that, with respect to sensitivity, specificity and accuracy, there was no statistically significant difference between EUS and MRCP for the detection of choledocholithiasis. Our meta-analysis of prospective comparison of MRCP and EUS for the detection of choledocholithiasis yielded statistically similar diagnostic values for both techniques.

Identification of risk factors for stone recurrence after endoscopic treatment of bile duct stones

Recurrence of bile duct stones after endoscopic stone removal has been reported ranging from 4 to 24%. The risk of late complications such as stone recurrence is an important issue, especially for relatively young, otherwise healthy, patients with many years of future exposure time. The risk factors true recurrence of bile duct stones after endoscopic sphincterotomy (EST) and stone clearance are suboptimally defined. If patients at significant risk for stone recurrence could be identified, closer follow-up, earlier intervention, and possible preventive measures could theoretically decrease stone recurrence and late complications. The majority of patients with common bile duct stone who have EST and stone clearance will have no further biliary events during the remainder of their life. Whether identifying risk factors for recurrence can improve outcomes by prophylactic treatments or earlier interventions needs further prospective study.

Nonoperative imaging techniques in suspected biliary tract obstruction

Evaluation of suspected biliary tract obstruction is a common clinical problem. Clinical data such as history, physical examination, and laboratory tests can accurately identify up to 90% of patients whose jaundice is caused by extrahepatic obstruction. However, complete assessment of extrahepatic obstruction often requires the use of various imaging modalities to confirm the presence, level, and cause of obstruction, and to aid in treatment plan. In the present summary, the literature on competing technologies including endoscopic retrograde cholangiopancreatography (ERCP), percutaneous transhepatic cholangiopancreatography (PTC), endoscopic ultrasound (EUS), intraductal ultrasonography (IDUS), magnetic resonance cholangiopancreatography (MRCP), helical CT (hCT) and helical CT cholangiography (hCTC) with regards to diagnostic performance characteristics, technical success, safety, and cost-effectiveness is reviewed. Patients with obstructive jaundice secondary to choledocholithiasis or pancreaticobiliary malignancies are the primary focus of this review. Algorithms for the management of suspected obstructive jaundice are put forward based on current evidence. Published data suggest an increasing role for EUS and other noninvasive imaging techniques such as MRCP, and hCT following an initial transabdominal ultrasound in the assessment of patients with suspected biliary obstruction to select candidates for surgery or therapeutic ERCP. The management of patients with a suspected pancreaticobiliary condition ultimately is dependent on local expertise, availability, cost, and the multidisciplinary collaboration between radiologists, surgeons, and gastroenterologists.

Detection of common bile duct stones: comparison between endoscopic ultrasonography, magnetic resonance cholangiography, and helical-computed-tomographic cholangiography

OBJECTIVES

New modalities, namely, endoscopic ultrasonography (EUS), magnetic resonance cholangiopancreatography (MRCP), and helical computed-tomographic cholangiography (HCT-C), have been introduced recently for the detection of common bile duct (CBD) stones and shown improved detectability compared to conventional ultrasound or computed tomography. We conducted this study to compare the diagnostic ability of EUS, MRCP, and HCT-C in patients with suspected choledocholithiasis.

METHODS

Twenty-eight patients clinically suspected of having CBD stones were enrolled, excluding those with cholangitis or a definite history of choledocholithiasis. Each patient underwent EUS, MRCP, and HCT-C prior to endoscopic retrograde cholangio-pancreatography (ERCP), the result of which served as the diagnostic gold standard.

RESULTS

CBD stones were detected in 24 (86%) of 28 patients by ERCP/IDUS. The sensitivity of EUS, MRCP, and HCT-C was 100%, 88%, and 88%, respectively. False negative cases for MRCP and HCT-C had a CBD stone smaller than 5mm in diameter. No serious complications occurred while one patient complained of itching in the eyelids after the infusion of contrast agent on HCT-C.

CONCLUSIONS

When examination can be scheduled, MRCP or HCT-C will be the first choice because they were less invasive than EUS. MRCP and HCT-C had similar detectability but the former may be preferable considering the possibility of allergic reaction in the latter. When MRCP is negative, EUS is recommended to check for small CBD stones.

The detection of bile duct stones in suspected biliary pancreatitis: comparison of MRCP, ERCP, and intraductal US

OBJECTIVES

Early ERCP and endoscopic sphincterotomy for stone extraction can benefit the prognosis in patients with severe biliary pancreatitis, but are associated with complications. The ability to identify choledocholithiasis by noninvasive means in biliary pancreatitis is limited. The aim of this study was evaluation of the ability of MRCP to detect choledocholithiasis in patients with acute biliary pancreatitis. In addition, we investigated whether intraductal US (IDUS) could help manage these patients.

METHODS

Thirty-two patients with suspected biliary pancreatitis were studied prospectively. MRCP was performed immediately before ERCP by separate blinded examiners within 24 h of admission. Wire-guided IDUS was performed during ERCP within 72 h of admission, regardless of the results of MRCP. Using endoscopic extraction of a stone as the reference standard, the diagnostic yield of MRCP was compared with transabdominal US, CT, ERCP, and IDUS.

RESULTS

The sensitivity of US, CT, MRCP, ERCP, and IDUS for identifying choledocholithiasis was 20.0%, 40.0%, 80.0%, 90.0%, and 95.0%, respectively. The overall agreement between MRCP and ERCP was 90.6% for choledocholithiasis (kappa= 0.808, p < 0.01). The sensitivity of MRCP for detecting choledocholithiasis decreased with dilated bile ducts (bile duct diameter > 10 mm, 72.7% vs 88.9%). The combination of ERCP and IDUS improved accuracy in the diagnosis of choledocholithiasis.

CONCLUSIONS

MRCP can be used to select patients with biliary pancreatitis who require ERCP. IDUS may be applied in the management of biliary pancreatitis if ERCP is performed.

Endoscopic ultrasonograpy for choledocholithiasis and biliary malignancy

Endoscopic ultrasound (EUS) is a valuable tool in gastrointestinal endoscopy, with various applications such as diagnosis, staging, and evaluation of the pancreaticobiliary system. EUS has comparable sensitivity to magnetic resonance cholangiopancreatography and endoscopic retrograde cholangiopancreatography (ERCP) for detection of choledocholithiasis. EUS may be considered for evaluation for choledocholithiasis as prelude to ERCP when there is a low to intermediate suspicion for common bile duct stones or when there is an increased risk for complications from ERCP. Endosonography may also be useful in the evaluation of cholangiocarcinoma. Intraductal ultrasound within the bile duct may help differentiate malignant from benign strictures. EUS-guided fine needle aspiration can be helpful in the diagnosis of cholangiocarcinoma, especially in the region of the hilum.

Role of endoscopic ultrasonography in diseases of the extrahepatic biliary system

Endoscopic ultrasonography (EUS) is one of the most recent advances in gastrointestinal endoscopy. Available EUS devices include echoendoscopes, such as radial scanning and linear array echoendoscopes, and catheter ultrasound probes. Endoscopic ultrasonography has various applications, such as staging of gastrointestinal malignancy, evaluation of submucosal tumors, and has grown to be an important modality in evaluating the pancreaticobiliary system. With regard to the biliary system, EUS is useful for the detection and staging of ampullary tumors, detection of microlithiasis and choledocholithiasis and evaluation of benign and malignant bile-duct strictures. Endoscopic ultrasonography may be used as an adjunct to transabdominal ultrasound for the detection and characterization of gallbladder polyps. In addition, EUS is helpful in the staging of gallbladder cancer as well as in diagnosing anomalous pancreaticobiliary junction with its associated pancreatobiliary diseases. The present paper reviews the current applications of EUS for imaging and intervention in diseases of the extrahepatic biliary system.

Innovative methods of biliary tract diagnosis: intraductal ultrasound and tissue acquisition

Tissue can be acquired from the bile and pancreatic duct with either brush cytology or biopsy forceps, often without the need for sphincterotomy. Although the diagnosis of malignancy with these sampling techniques is often specific, the sensitivity is limited, and a wide range of diagnostic accuracies has been reported. A combination of biopsy and brush cytology along with some newer techniques in the development stage may increase the sensitivity. Intraductal ultrasound is a newer technique offers the endoscopist the ability to image the bile and pancreatic duct wall, adjacent organs, and vascular structures with a high degree of detail. This visualization can be accomplished during the course of an ERCP or percutaneously under fluoroscopic guidance. Indications for the procedure include detection of choledocholithiasis, differentiation of benign and malignant ductal strictures, pancreaticobiliary tumor staging, and detection of various pancreatic tumors. Continued research into the design of the probes, which could improve durability and extend the depth of penetration, may promote more widespread use of this novel technology.

Clinical utility of intraductal US for evaluation of choledocholithiasis

BACKGROUND

Intraductal US can improve the diagnostic accuracy of cholangiography performed under C-arm fluoroscopy in patients with suspected choledocholithiasis. This study aimed to determine the clinical utility of intraductal US for patient management.

METHODS

Patients with suspected choledocholithiasis undergoing ERCP with a C-arm fluoroscope at two tertiary academic medical centers were enrolled. After initial cholangiography, findings and decisions concerning the need for further interventions were recorded. Intraductal US (20 MHz) was then selectively performed in patients with equivocal cholangiography or those without cholangiographic evidence of bile duct stones. Intraductal US was also performed after endoscopic sphincterotomy and stone extraction to confirm bile duct clearance.

RESULTS

Fifty-two patients (28 men, 24 women) were enrolled and intraductal US was selectively performed in 35 (64%). Of the 21 patients with normal cholangiography, 8 (38%) had stones or sludge by intraductal US. Endoscopic sphincterotomy was performed as a direct result of intraductal US in these 8 and the findings were confirmed in 7. In the 14 patients in whom cholangiography demonstrated small (<5 mm) or round filling defects, intraductal US concurred in 9 and found air bubble/no stone in 5. Sphincterotomy was avoided in these 5 patients. Overall, intraductal US led to a change in clinical management in 13 of 35 patients (37%) in whom it was performed.

CONCLUSIONS

Selective use of intraductal US affects the clinical management of a large proportion of patients who undergo C-arm fluoroscopy-guided ERCP for suspected bile duct stones.

Intraductal US is a useful adjunct to ERCP for distinguishing malignant from benign biliary strictures

BACKGROUND

Distinguishing malignant from benign biliary strictures remains a challenge. This prospective study assessed intraductal US as an adjunct to endoscopic retrograde cholangiography and tissue sampling for diagnosis of malignant and benign biliary strictures.

METHODS

Sixty-two patients were enrolled who had biliary strictures suspected to be malignant but with negative tissue sampling by endoscopic retrograde cholangiography, or suspected biliary strictures based on clinical manifestations and/or cross-sectional imaging. Intraductal US was performed with an over-the-wire 2.4-mm diameter 20 MHz catheter US probe. The diagnostic accuracy of endoscopic retrograde cholangiography plus tissue sampling with and without intraductal US was compared with surgical findings or clinical outcome at a 12-month follow-up (benign/malignant) in nonsurgical cases. Tissue sampling results were reported as malignant, suspicious for malignancy, atypical, or normal. Analysis was by intention-to-treat.

RESULTS

Two patients (3%) were excluded from analysis because the stricture could not be traversed with the intraductal US probe. Of the 60 remaining patients (37 men, mean age 64 years, range 27-89 years), 31 had malignant strictures (12 cholangiocarcinoma, 8 pancreatic, 5 metastatic, 3 gallbladder, 3 papilla), and 29 had benign strictures. Sphincterotomy was not required in any case to facilitate intraductal US. Fourteen patients (23%) underwent subsequent surgery including 11 with a preoperative diagnosis of resectable tumor. Endoscopic retrograde cholangiography/tissue sampling (atypia considered equivalent to benign) correctly identified 15 of 31 malignant strictures (p = 0.001) and all 29 benign strictures (p = 0.16) (accuracy 73%, sensitivity 48%, specificity 100%). The addition of intraductal US correctly identified 28 of 31 malignant strictures and 27 of 29 benign strictures (accuracy 92%, sensitivity 90%, specificity 93%). Of 11 patients with tumors who came to surgery, intraductal US correctly staged 4 (36%), understaged 5 (45%), missing metastatic lymph nodes in all cases and vascular invasion in 1 patient, and overstaged 2 (18%), with a false-positive diagnosis of metastatic lymph nodes in 1 and tumor mass in 1 patient who had no cancer at surgery.

CONCLUSION

Technically easy, intraductal US is a valuable adjunct to endoscopic retrograde cholangiography/tissue sampling that increases the ability to distinguish malignant from benign strictures. Intraductal US is unsuitable for assessing lymph nodes associated with malignant strictures.