Intraductal Ultrasonography Research Articles

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.

Endoscopic Retrograde Cholangiopancreatography-Related Procedures for the Differential Diagnosis of Isolated Immunoglobin G4-Related Sclerosing Cholangitis and Perihilar Cholangiocarcinoma.

Differential diagnosis of isolated immunoglobin (Ig)G4-related sclerosing cholangitis (IgG4-SC) and cholangiocarcinoma is challenging. We aimed to clarify the role of endoscopic retrograde cholangiography (ERCP)-related procedures in the differential diagnosis of isolated IgG4-SC and perihilar cholangiocarcinoma (PHCC). Seven patients with hilar-type isolated IgG4-SC diagnosed at Hiroshima University Hospital and sixty-five patients with surgically resected invasive PHCC were enrolled, and the diagnostic yields of intraductal ultrasonography (IDUS), peroral cholangioscopy (POCS), and pathological examinations were determined. In six of seven (86%) patients with isolated IgG4-SC, the stricture was in the perihilar bile duct. IDUS showed that symmetrical wall thickening (40% vs. 5%, p = 0.04), homogeneous internal echo (80% vs. 5%, p < 0.001), and smooth outer margins (80% vs. 6%, p < 0.001) were more frequent in isolated IgG4-SC than in PHCC. POCS showed a smooth mucosal surface more frequent in isolated IgG4-SC (75% vs. 7%, p = 0.006). Only one patient had two pathological findings characteristic of IgG4-SC. The sensitivity for diagnosing PHCC was 81% using two or more combined sampling methods. Pathological examinations have limitations in the differential diagnosis of isolated-IgG4-SC and PHCC, and a diagnostic strategy that combines multiple ERCP-related procedures, including IDUS and POCS, is recommended.

Intraoperative intraductal ultrasonography of the main pancreatic duct during pancreatoduodenectomy: technical description of a pilot series.

The intraoperative risk stratification during pancreatoduodenectomy is gaining increasing significance. The main pancreatic duct wall is of particular importance as it represents the element of anchor of the anastomotic stiches. This study aims to describe the safety, feasibility, and reproducibility of a novel intraductal ultrasonography of the main pancreatic (MPD)-Wirsung duct (IWU) during pancreatoduodenectomy (PD).A prospective series of 58 patients underwent PD with anastomosis between the MPD and the jejunum. Just before the reconstructive phase, the remaining pancreatic stump underwent complete IWU with definition of Wirsung thickness (WT) at the anastomotic site, using a radial ultrasound probe of 1.7mm in diameter.No IWU-related complications were reported. The median WT of the MPD was 1.1mm (SD 0.2). The rates of postoperative pancreatic fistula (POPF), major morbidity, and mortality were 17, 5, and 0%, respectively.The use of IWU during PD demonstrated safety and feasibility. IWU represents a new tool aimed at determining structural characteristics of the MPD that could impact on the surgical strategy of the pancreatic anastomosis. Further validation and comparative analysis with the current standard of care are warranted within a prospective controlled framework.

Hepatopancreatoduodenectomy with delayed division of the pancreatic parenchyma when utilizing a right lateral approach to the superior mesenteric artery

BackgroundHepatopancreatoduodenectomy (HPD) is a high-risk surgical procedure. Delayed division of the pancreatic parenchyma (DDPP) was reported as a novel technique in HPD for reducing postoperative pancreatic fistula. However, it is often difficult to dissect the pancreatic head nerve plexus while leaving the pancreatic parenchyma intact, particularly in patients with a bulky tumor with vascular invasion. Of the various reported approaches to the superior mesenteric artery, the right lateral approach can provide a useful surgical field to conduct DDPP in HPD.Case presentationA 78-year-old man visited a local clinic with itching and jaundice. Laboratory tests revealed elevated hepatobiliary enzyme, total bilirubin, and tumor markers. Enhanced computed tomography, endoscopic retrograde cholangiopancreatography, and intraductal ultrasonography of the bile duct were performed, and he was diagnosed with perihilar cholangiocarcinoma with invasion to the right hepatic artery (40 × 15 mm, Bismuth IIIa, cT3N0M0 cStage III). After neoadjuvant chemotherapy, he underwent left hepatectomy with caudate lobectomy, pancreatoduodenectomy, and combined resection of right hepatic artery using DDPP with a right lateral approach to the superior mesenteric artery. The pathological diagnosis was perihilar cholangiocarcinoma ypT3N1M0 ypStage IIIC, R0 resection. He was discharged on postoperative day 57 in good health and has been doing well for 6 months since the surgery.ConclusionsWe present an effective application of the right lateral approach to the superior mesenteric artery in DDPP during HPD. This procedure can provide a clear surgical field to easily divide the pancreatic head nerve plexus before transection of the pancreatic parenchyma.

Direct Single-Operator Cholangioscopy and Intraductal Ultrasonography in Patients with Indeterminate Biliary Strictures: A Single Center Experience.

The evaluation of biliary strictures poses a challenge due to the low sensitivity of standard diagnostic approaches, but the advent of direct single-operator cholangioscopy (DSOC) has revolutionized this paradigm. Our study aimed to assess the diagnostic performance of DSOC and DSOC-targeted biopsies, intraductal ultrasound (IDUS), and standard brush cytology in patients with indeterminate biliary strictures (IBS). We reviewed patients who underwent advanced diagnostic evaluation for IBS at our endoscopy unit from January 2018 to December 2022, all of whom had previously undergone at least one endoscopic attempt to characterize the biliary stricture. Final diagnoses were established based on surgical pathology and/or clinical and radiological follow-up spanning at least 12 months. A total of 57 patients, with a mean age of 67.2 ± 10.0 years, were included, with a mean follow-up of 18.2 ± 18.1 months. The majority of IBS were located in the distal common bile duct (45.6%), with malignancy confirmed in 35 patients (61.4%). DSOC and IDUS demonstrated significantly higher accuracies (89.5% and 82.7%, respectively) compared to standard cytology (61.5%, p < 0.05). Both DSOC visualization and IDUS exhibited optimal diagnostic yields in differentiating IBS with an acceptable safety profile.

Diagnostic accuracy of cross-sectional and endoscopic imaging in ampullary tumours: systematic review.

Differentiation between adenomas and carcinomas of the ampulla of Vater is crucial for therapy and prognosis. This was a systematic review of the literature on the accuracy of diagnostic modalities used to differentiate between benign and malignant ampullary tumours. A literature search was conducted in PubMed, Embase, CINAHL, and the Cochrane Library. Studies were included if they reported diagnostic test accuracy information among benign and malignant ampullary tumours, and used pathological diagnosis as the reference standard. Risk of bias was assessed using Quality Assessment on Diagnostic Accuracy Studies (QUADAS) 2 and QUADAS-C. Ten studies comprising 397 patients were included. Frequently studied modalities were (CT; 2 studies), endoscopic ultrasonography (EUS; 3 studies), intraductal ultrasonography (IDUS; 2 studies), and endoscopic forceps biopsy (3 studies). For CT, the reported sensitivity for detecting ampullary carcinoma was 44 and 95%, and the specificity 58 and 60%. For EUS, the sensitivity ranged from 63 to 89% and the specificity between 50 and 100%. A sensitivity of 88 and 100% was reported for IDUS, with a specificity of 75 and 93%. For forceps biopsy, the sensitivity ranged from 20 to 91%, and the specificity from 75 to 86%. The overall risk of bias was scored as moderate to poor. Data were insufficient for meta-analysis. To differentiate benign from malignant ampullary tumours, EUS and IDUS seem to be the best diagnostic modalities. Sufficient high-quality evidence, however, is lacking.

Evaluation of a Novel Easy Loop-Forming Guidewire to Reduce Post-Endoscopic Retrograde Cholangiopancreatography Pancreatitis for Serial Pancreatic Juice Aspiration Cytologic Examination: A Propensity Score Matching Analysis.

This study aimed to investigate whether a novel, easy loop-forming guidewire could reduce post-endoscopic retrograde cholangiopancreatography pancreatitis (PEP) in patients undergoing endoscopic nasopancreatic drainage tube placement for serial pancreatic juice aspiration cytologic examination (SPACE). We evaluated patients with suspected pancreatic cancer who underwent SPACE at our institution between January 2015 and April 2023 retrospectively. The patients were divided into 2 groups based on the type of guidewire used, namely, easy loop-forming and control groups. Propensity score matching was used to compare the incidence of PEP between the groups. We included 101 patients, with 51 and 50 in the easy loop-forming and control groups, respectively. After propensity score matching, 29 pairs of patients were selected from each group. Intraductal ultrasonography of the pancreas was performed more frequently in the easy loop-forming group than in the control group (27.6% vs 0%; P = 0.004); however, PEP incidence was significantly lower in the easy loop-forming group than in the control group (3.4% vs 27.6%; odds ratio, 0.097; 95% confidence interval, 0.002-0.82; P = 0.025). The use of the novel easy loop-forming guidewire decreased PEP occurrence in patients who underwent endoscopic nasopancreatic drainage tube placement for SPACE.

Accuracy and limitations of preoperative assessment of longitudinal spread of perihilar cholangiocarcinoma.

Although surgical resection offers the only chance of cure of perihilar cholangiocarcinoma and R1 resection has a poor prognosis, there is no consensus on optimal preoperative assessment of its longitudinal spread. We aimed to establish the optimal means of achieving this goal. This was a retrospective, single-center study of 61 patients who had undergone multi-detector row computed tomography, endoscopic retrograde cholangiography, intraductal ultrasonography, and mapping biopsy prior to resection of perihilar cholangiocarcinomas in our institute from January 2010 and December 2021. The most accurate single methods for assessing longitudinal spread were intraductal ultrasonography and mapping biopsy (both 72.1%). A combination of all four assessment methods was accurate in 51 (83.6%) of our patients. Independent risk factors for inaccuracy were Bismuth-Corlette Type IV and high histologic-grade tumors. The R0 resection rate was higher with accurate than inaccurate assessments (90.2% vs. 30.0%, P<0.001). R0 resection was associated with significantly better relapse-free survival than R1 resection (P=0.006). However, overall survival did not differ between these groups. Preoperative assessment of longitudinal spread of perihilar cholangiocarcinomas by four different modalities is optimal, achieving 83.6% accuracy and a 90.2% R0 resection rate.

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.

Preventive Saline Irrigation of the Bile Duct to Reduce the Rate of Residual Common Bile Duct Stones Without Intraductal Ultrasonography: A Systematic Review and Meta-Analysis.

Endoscopic retrograde cholangiopancreatography (ERCP) with endoscopic sphincterotomy (EST) has been proven efficacious in the removal of CBD stones. Even after endoscopic stone removal, recurring cholangitis due to a residual common bile duct (CBD) stone is prevalent in clinical practice with a residual recurrence rate of 4-24% after successful stone retrieval. This comprehensive study and meta-analysis aimed to determine if preventive saline irrigation of the bile duct (PSIB) reduces the amount of residual CBD stones. Through a comprehensive search of PubMed, EMBASE, Cochrane Library, and Web of Science until November 20, 2022, we identified 164 articles comparing the efficacy of PSIB and non-PSIB post-endoscopic CBD stone removal. After stringent selection, three studies were included for meta-analysis using ReviewManager (ReVman version 5.4.1; Cochrane, London, UK). Using a random effect (RE) model, we derived a pooled odds ratio (OR) with confidence interval (CI) (95%CI). A total of three studies have been included in the analysis. Out of which, two are randomized controlled trials (RCTs) and one is a non-randomized study. Out of 323 patients, 157 underwent PSIB after an endoscopic stone removal of CBD stones to reduce the residual of CBD stones, whereas 166 did not undergo saline irrigation (non-PSIB). In our analysis, PSIB significantly reduced the risk of residual stones (OR: 0.22, 95%CI: 0.11-0.45). However, there was no notable link between PSIB and post-irrigation cholangitis (OR: 1.08, 95%CI: 0.21-2.21). Although not statistically significant, PSIB showed a trend toward lowered risks of post-procedural pancreatitis (OR: 0.65), bleeding (OR: 0.68), and other complications (OR: 0.64). PSIB effectively reduces residual CBD stones after endoscopy, offering a cost-effective alternative to invasive procedures such as intraductal ultrasound (IDUS). However, larger RCTs are needed to validate its definitive role.

Artificial intelligence in a prediction model for postendoscopic retrograde cholangiopancreatography pancreatitis.

In this study we aimed to develop an artificial intelligence-based model for predicting postendoscopic retrograde cholangiopancreatography (ERCP) pancreatitis (PEP). We retrospectively reviewed ERCP patients at Nagoya University Hospital (NUH) and Toyota Memorial Hospital (TMH). We constructed two prediction models, a random forest (RF), one of the machine-learning algorithms, and a logistic regression (LR) model. First, we selected features of each model from 40 possible features. Then the models were trained and validated using three fold cross-validation in the NUH cohort and tested in the TMH cohort. The area under the receiver operating characteristic curve (AUROC) was used to assess model performance. Finally, using the output parameters of the RF model, we classified the patients into low-, medium-, and high-risk groups. A total of 615 patients at NUH and 544 patients at TMH were enrolled. Ten features were selected for the RF model, including albumin, creatinine, biliary tract cancer, pancreatic cancer, bile duct stone, total procedure time, pancreatic duct injection, pancreatic guidewire-assisted technique without a pancreatic stent, intraductal ultrasonography, and bile duct biopsy. In the three fold cross-validation, the RF model showed better predictive ability than the LR model (AUROC 0.821 vs. 0.660). In the test, the RF model also showed better performance (AUROC 0.770 vs. 0.663, P = 0.002). Based on the RF model, we classified the patients according to the incidence of PEP (2.9%, 10.0%, and 23.9%). We developed an RF model. Machine-learning algorithms could be powerful tools to develop accurate prediction models.

Application of endoscopic retrograde cholangiopancreatography combined with intraductal ultrasonography in differential diagnosis of enign and malignant biliary stricture and nursing management

Application of endoscopic retrograde cholangiopancreatography combined with intraductal ultrasonography in differential diagnosis of enign and malignant biliary stricture and nursing management

Intraductal ultrasonography for biliary strictures.

When diagnosing the nature of biliary strictures, it is sometimes difficult to perform non-invasive methods such as ultrasound, spiral computed imaging, magnetic resonance imaging, or endoscopic ultrasonography. Thus, treatment decisions are usually based on biopsy results. However, brush cytology or biopsy, which is widely used for biliary stenosis, has limitations owing to its low sensitivity and negative predictive value for malignancy. Currently, the most accurate method is bile duct tissue biopsy under direct cholangioscopy. On the other hand, intraductal ultrasonography administered under the guidance of a guidewire has the advantages of easy administration and being less invasive, allowing for adequate examination of the biliary tract and surrounding organs. This review discusses the usefulness and drawbacks of intraductal ultrasonography for biliary strictures.

Endoscopic retrograde cholangiopancreatography and intraductal ultrasonography in the diagnosis of autoimmune pancreatitis and IgG4-related sclerosing cholangitis

Endoscopic retrograde cholangiopancreatography and intraductal ultrasonography in the diagnosis of autoimmune pancreatitis and IgG4-related sclerosing cholangitis

A novel technique of intraductal ultrasonography using a newly designed endoscopic sheath and Y-connector during endoscopic retrograde cholangiography.

A novel technique of intraductal ultrasonography using a newly designed endoscopic sheath and Y-connector during endoscopic retrograde cholangiography.

Preferable timing of intraductal ultrasonography during endoscopic retrograde cholangiopancreatography lithotomy: A prospective cohort study.

Intraductal ultrasonography (IDUS) is a highly sensitive and non-invasive detective method that can be used to detect complete calculus clearance during endoscopic retrograde cholangiopancreatography (ERCP). In this study, we examined the preferable timing of IDUS during ERCP lithotomy. From 2017 to 2020, patients with choledocholithiasis were randomized into IDUS-BL (IDUS performed before lithotomy) group, IDUS-ALC (cholangiography and IDUS performed after lithotomy) group, and IDUS-AL group (IDUS performed after lithotomy) group. The influence of IDUS on the accuracy of prejudgment, the incidence of residual stones, the need for repeated lithotomy (RL), and fluoroscopy time were analyzed. A total of 184 patients were enrolled. No residual stones were found during follow-up in any of the three groups. There was no difference in prejudgment accuracy rate on size and number of stones between different groups (all P > 0.05). RL were performed in 5, 9, and 9 cases of IDUS-BL, IDUS-ALC, and IDUS-AL group, respectively (P > 0.05). IDUS-AL group had a shorter fluoroscopy time than the other two groups (1.5 ± 0.6 vs. 2.8 ± 1.2, 2.5 ± 1.0 min, P < 0.05). Incidence of RL was related to the location of calculus [middle or lower part of common bile duct (CBD)], lithotripsy, dilated CBD (2.12 ± 0.46 vs. 1.78 ± 0.40 cm, P < 0.01), and inaccuracy prejudgment. IDUS performed after lithotomy is preferable for shorten fluoroscopy time during ERCP. IDUS is a reliable solution for the stone omission, which may be more valuable for patients with high-risk factors of RL.

Screening for hilar biliary invasion in ampullary cancer patients.

BACKGROUNDThe treatment for ampullary cancer is pancreatoduodenectomy or local ampullectomy. However, effective methods for the preoperative investigation of hilar biliary invasion in ampullary cancer patients have not yet been identified.AIMTo determine the necessity of and an appropriate method for investigating hilar biliary invasion of ampullary cancer.METHODSAmong 43 ampullary cancer patients, 34 underwent endoscopic treatment (n = 9) or surgery (n = 25). The use of imaging findings (thickening and enhancement of the bile duct wall on contrast-enhanced computed tomography, irregularity on endoscopic retrograde cholangiography, thickening of the entire bile duct wall on intraductal ultrasonography (IDUS), and partial thickening of the bile duct wall on IDUS) and biliary biopsy results for diagnosing hilar biliary invasion of ampullary cancer was compared.RESULTSHilar invasion was not observed in every patient. Among the patients who did not undergo biliary stent insertion, the combination of partial thickening of the bile duct wall on IDUS and biliary biopsy results showed the highest accuracy (100%) for diagnosing hilar biliary invasion. However, each imaging method and biliary biopsy yielded some false-positive results.CONCLUSIONAlthough some false-positive results were obtained with each method, the combination of partial thickening of the bile duct wall on IDUS and biliary biopsy results was useful for diagnosing hilar biliary invasion of ampullary cancer. However, hilar invasion of ampullary cancer is rare; therefore, the investigation of hilar biliary invasion of ampullary cancer might be unnecessary.

Cholangioscopic diagnosis of biliary amyloidosis presenting as bile duct obstruction with cholangitis (with video)

A 73-year-old woman with a history of cardiac amyloidosis presented with obstructive jaundice and upper right postprandial abdominal pain. Computed tomography yielded findings suggestive of common bile duct stones with acute cholangitis. A cholangiogram demonstrated 2 oval filling defects in the common bile duct (A). Intraductal US revealed hypoechoic, homogenous submucosal mass lesions (B). Single-operator cholangioscopy (SpyGlass DS II, Boston Scientific, Marlborough, Mass, USA) showed a protruding mass lesion with tortuous and dilated vessels and central ulceration (C) (Video 1, available online at www.giejournal.org). SpyBite Max forceps biopsy was performed to confirm the pathologic diagnosis. Analysis of the biopsy specimen revealed pink-red deposits in the area of eosinophilic material, consistent with amyloidosis (D, Congo red stain, orig. mag. ×200).

Papillary Cholangiocarcinoma Located in the Distal Common Bile Duct

Papillary tumors are the rarest form of cholangiocarcinoma, usually present as intraductal masses in the common bile duct (CBD), which cause obstructive jaundice early in the course of the disease. A 66-year-old female had jaundice for one month. Abdominal ultrasonography revealed a 2-cm-sized hypoechoic mass located in the distal CBD with upstream biliary tree dilatation. Computed tomography and magnetic resonance imaging suggested the possibility of extrahepatic cholangiocarcinoma. We performed endoscopic retrograde cholangiopancreatography with intraductal ultrasonography, revealing a papillary mass without definitive bile duct invasion located in the distal CBD. The patient underwent successful surgery and was diagnosed with stage T1N0M0 papillary adenocarcinoma. The patient is currently, one year after the surgery, under follow-up without recurrence.

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.