Interventional Endoscopic Ultrasound Research Articles

Dedicated Echoendoscope for Interventional Endoscopic Ultrasound: Comparison with a Conventional Echoendoscope

Interventional endoscopic ultrasound (I-EUS) is technically difficult and has risks of severe adverse events due to the scarcity of dedicated endoscopes and tools. A new EUS scope was developed for I-EUS and was modified to increase the puncture range, reduce the blind area, and overcome guidewire difficulties. We evaluated the usefulness and safety of a new EUS scope compared to a conventional EUS scope. Methods: All I-EUS procedures were performed at Juntendo University Hospital from April 2020 to April 2022. The primary outcomes included the procedure time and fluoroscopy time. The secondary outcomes included the technical success rate and the rates of procedure-related adverse events. Clinical data were retrospectively reviewed and statistically analyzed between the new and conventional EUS scopes. Results: In total, 143 procedures in 120 patients were analyzed. The procedure time was significantly shorter with the new EUS scope, but the fluoroscopy time was not different. Among the patients only undergoing EUS-guided biliary drainage (EUS-BD), 79 procedures in 74 patients were analyzed. Both the procedure time and fluoroscopy time were significantly shorter with the new EUS scope. Multivariate analysis revealed that a new EUS scope and use of covered metal stents could reduce the fluoroscopy time. The technical success rate and the adverse event rate were not significantly different between the total I-EUS and the EUS-BD only groups. However, the conventional scope showed stent deviation during stent placement, which did not happen with the new scope. Conclusions: The new EUS scope reduced procedure time for total I-EUS and fluoroscopy time for EUS-BD compared to a conventional EUS scope because of the improvement suitable for I-EUS.

Impact and assessment of training models in interventional endoscopic ultrasound.

Interventional endoscopic ultrasound (IEUS) has gained significant popularity in recent years because of its diagnostic and therapeutic capabilities. The proper training of endoscopists is critical to ensure safe and effective procedures. This review study aims to assess the impact of different training models on the competence of trainees performing IEUS. Eight studies that evaluated simulators for IEUS were identified in the medical literature. Various training models have been used, including the EASIE-R, Mumbai EUS, EUS Magic Box, EndoSim, Thai Association for Gastrointestinal Endoscopy model, and an exvivo porcine model (HiFi SAM). The trainees underwent traditional didactic lectures, hands-on training using simulators, and direct supervision by experienced endoscopists. The effectiveness of these models has been evaluated based on objective and subjective parameters such as technical proficiency, operative time, diagnostic success, and participant feedback. As expected, the majority of skills were improved after the training sessions concluded, although the risk of bias is high in the absence of external validation. It is difficult to determine the ideal simulator among the existing ones because of the wide variation between them in terms of costs, reusability, design, fidelity of anatomical structures and feedback, and types of procedures performed. There is a need for a standardized approach for the evaluation of IEUS simulators and the ways skills are acquired by trainees, as well as a clearer definition of the key personal attributes necessary for developing a physician into a skilled endoscopist capable of performing basic and advanced therapeutic EUS interventions.

Utility of interventional endoscopic ultrasound in pancreatic cancer.

Endoscopic ultrasound (EUS) has an important role in the management algorithm of patients with pancreatic ductal adenocarcinoma (PDAC), typically for its diagnostic utilities. The past two decades have seen a rapid expansion of the therapeutic capabilities of EUS. Interventional EUS is now one of the more exciting developments within the field of endoscopy. The local effects of PDAC tend to be in anatomical areas which are difficult to target and endoscopy has cemented itself as a key role in managing the clinical sequelae of PDAC. Interventional EUS is increasingly utilized in situations whereby conventional endoscopy is either impossible to perform or unsuccessful. It also adds a different dimension to the host of oncological and surgical treatments for patients with PDAC. In this review, we aim to summarize the various ways in which interventional EUS could benefit patients with PDAC and aim to provide a balanced commentary on the current evidence of interventional EUS in the literature.

THE IMPACT OF THE COVID-19 PANDEMIC ON ENDOSCOPIC ULTRASOUND PROCEDURES IN A HIGH-VOLUME ENDOSCOPY UNIT IN BRAZIL.

•In pancreatic neoplasms the EUS plays a key role in the management. •During the pandemic period, lockdown measures prevented patients with comorbidities from performing EUS. •The D-EUS decreased during COVID-19, while I-EUS increased and EUS-TA was the most commonly I-EUS procedure performed, with no increase in adverse events. •Despite the moderate impact of the pandemic period in endoscopic services around the world, EUS-TA of solid and cystic tumors of the pancreas was the main indication. Background - Reports of the impact of the 2020 COVID-19 pandemic period/2020 on endoscopic ultrasound (EUS) are scarce. Objective - We analyzed the impact of the pandemic period/2020 on the demographics, indications, and number of diagnostic EUS (D-EUS) and interventional EUS (I-EUS) procedures performed in a high-volume endoscopy unit compared with the previous non-pandemic period/2019. Methods - We retrospectively reviewed the medical records of all patients undergoing D-EUS or I-EUS from March 1, 2019, to February 29, 2020 (non-pandemic period/2019) and from March 1, 2020, to February 28, 2021 (pandemic period/2020). Data compared between the study periods included sex, age, comorbidities, EUS findings and diagnosis, need for interventional procedures during EUS, and adverse events (AEs). Results were significant at P<0.05. Results - EUS procedures decreased from 475 in the non-pandemic period/2019 to 289 in the pandemic period/2020, accounting for a 39% reduction. In non-pandemic period/2019, 388 (81.7%) D-EUS and 88 (18.5%) I-EUS were performed, against 206 (71.3%) D-EUS and 83 (28.7%) I-EUS in pandemic period/2020 (P=0.001). Only 5/289 (1.7%) patients had COVID-19. Fewer patients with comorbidities underwent EUS during pandemic period/2020 due to lockdown measures (P<0.001). D-EUS decreased, whereas I-EUS increased (P<0.001). EUS-guided tissue acquisition (EUS-TA) was the most common I-EUS, performed in 83/289 (28.7%) patients in pandemic period/2020, against 88/475 (18.5%) in non-pandemic period/2019 (P=0.001). AEs did not differ significantly between the study periods. Conclusion - Pandemic Period/2020 had a moderate impact on reducing EUS procedures due to the risks involved. Although I-EUS increased, EUS-related AEs did not. Solid and cystic pancreatic tumors remained a major indication for EUS-TA even during the pandemic period/2020.

Endoscopic ultrasound-guided colo-colostomy for the treatment of benign complete occlusion of colonic anastomosis: a case series and description of technique.

The incidence of benign colonic anastomotic stricture is approximately 2% in patients undergoing left hemicolectomy or anterior resection and as high as 16% in patients undergoing low anterior or intersphincteric resection. In the majority, rather than complete occlusion, a stenosis forms, which can be managed with endoscopic balloon dilatation, a self-expanding metallic stent or endoscopic electroincision. In the less common scenario of a completely occluded colonic anastomosis, surgery is often required. In this study, we aim to describe the technique we used to treat this condition non-operatively METHOD: We describe a case series of three patients with benign complete occlusion of their colorectal anastomosis and how we managed them nonoperatively with a colonic/rectal endoscopic ultrasound (EUS) anastomosis technique and a Hot lumen-apposing metallic stent. We demonstrate that the technical and clinical success for this technique is 100%. We believe that the technique we describe is effective and safe. It should be widely reproducible in centres with expertise in interventional EUS, given the similarity to well-established procedures such as EUS-guided gastroenterostomy. Patient selection and timing of reversal of ileostomy need careful consideration, especially in patients with a history of keloid formation. Given the shorter hospital stay and reduced invasiveness of this technique, we believe it should be considered for all patients who have complete benign occlusion of a colonic anastomosis. However, given the small number of cases and short period of follow-up, the long-term outcome of this technique is not known. More studies with higher power and a longer period of follow-up should be conducted to further ascertain the effectiveness of this technique.

Two-channel endoscope re-intervention for stent dysfunction after interventional endoscopic ultrasonography: forceps stabilization of stent for cutting by argon plasma coagulation

Two-channel endoscope re-intervention for stent dysfunction after interventional endoscopic ultrasonography: forceps stabilization of stent for cutting by argon plasma coagulation

Role of interventional endoscopic ultrasound in a developing country.

Endoscopic ultrasound (EUS) has become an essential diagnostic and therapeutic tool. EUS was introduced in 2013 in Indonesia and is considered relatively new. This study aimed to describe the current role of interventional EUS at our hospital as a part of the Indonesian tertiary health center experience. This retrospective study included all patients who underwent interventional EUS (n=94) at our center between January 2015 and December 2020. Patient characteristics, technical success, clinical success, and adverse events associated with each type of interventional EUS procedure were evaluated. Altogether, 94 interventional EUS procedures were performed at our center between 2015 and 2020 including 75 cases of EUS-guided biliary drainage (EUS-BD), 14 cases of EUS-guided pancreatic fluid drainage, and five cases of EUS-guided celiac plexus neurolysis. The technical and clinical success rates of EUS-BD were 98.6% and 52%, respectively. The technical success rate was 100% for both EUS-guided pancreatic fluid drainage and EUS-guided celiac plexus neurolysis. The adverse event rates were 10.6% and 7.1% for EUS-BD and EUS-guided pancreatic fluid drainage, respectively. EUS is an effective and safe tool for the treatment of gastrointestinal and biliary diseases. It has a low rate of adverse events, even in developing countries.

IMPACT OF DIAGNOSTIC AND INTERVENTIONAL ENDOSCOPIC ULTRASONOGRAPHY IN CHILDREN.

Endoscopic ultrasonography is used in the diagnosis and treatment of digestive diseases in adults. In children, its use is limited due to a lack of available expertise. This study aimed to evaluate the clinical impact of endoscopic ultrasonography on diagnostic and therapeutic strategy changes in pediatric patients. Over ten years, this study retrospectively and consecutively analyzed children aged ≤18 years who underwent endoscopic ultrasonography because of inconclusive imaging or laboratory tests. The indications, results, occurrence of adverse events, and clinical impact of the procedures were analyzed. The clinical impact was classified as major (when the findings led to changes in diagnosis and management), minor (change in diagnosis but not in management), or none (no change in diagnosis or management). Overall, 107 children [77 (72%) of whom were female; mean age: 11.7 ± 4 years] underwent upper [102 (95.3%)] and lower [5 (4.7%)] endoscopic ultrasonography; 64 (58%) patients underwent diagnostic endoscopic ultrasonography, and 43 (42%) underwent interventional endoscopic ultrasonography. Endoscopic ultrasonography was used to investigate pancreaticobiliary, gastric, rectal, esophageal, duodenal, and mediastinal diseases in 81 (76%), 14 (13%), 5 (4.6%), 3 (2.8%), 2 (1.8%), and 2 (1.8%) patients, respectively. The clinical impact was significant in 81% of the children. Major and no clinical impact on pancreaticobiliary, gastrointestinal diseases, and mediastinal masses occurred in 50 (62%) and 13 (16%), 13 (54%) and 9 (37%), and 2 (100%) and 0 (0%) of the patients, respectively. This study evaluated the impact of diagnostic and interventional endoscopic ultrasonography in pediatric patients. When clinically and appropriately indicated, these procedures are safe and effective diagnostic or therapeutic interventions in pediatric patients with gastrointestinal or pancreaticobiliary disorders.

Development of devices for interventional endoscopic ultrasound for the management of pancreatobiliary diseases.

A variety of devices have been developed for interventional endoscopic ultrasound (EUS). EUS-guided drainage of the bile duct and pancreatic duct, as well as fluid collection adjacent to the gastrointestinal tract, is performed by a procedure involving puncture, guidewire manipulation, tract dilation, and stent placement. Devices specialized for interventional EUS are being developed for each step of the procedure. Mechanical dilators such as bougie, balloon, and electrocautery dilators are used for tract dilation. Various types of plastic stents, self-expandable metal stents, and lumen-apposing metal stents specifically designed for interventional EUS are now available, including one-step devices developed to improve the efficacy and safety of interventional EUS. In addition, radiofrequency ablation and the placement of fiducial markers and radioactive seeds under EUS guidance are now becoming established for pancreatic neoplasms. Such development of specialized devices has expanded the indications for interventional EUS, increased the success rate, and lowered the adverse event rate.

S348 Creating Your Own Paths: EUS-Guided Transjejunal Gallbladder Drainage and ERCP, Cholecystoscopy, and Electrohydraulic Lithotripsy for Choledocholithiasis and Cholelithiasis in a Patient With Roux-en-Y Gastric Bypass

Introduction: Treating choledocholithiasis and cholelithiasis in patients with altered gastrointestinal anatomy is a challenge given the difficulty in accessing the biliary tract using conventional endoscopic techniques. Endoscopic ultrasound (EUS) directed transgastric ERCP (EDGE) represents a novel solution to this challenge. It allows access to the excluded stomach allowing safe performance of ERCP and interventional EUS procedures including gallbladder drainage. Case Description/Methods: A 61-year-old man with a history of morbid obesity, Roux-en-Y gastric bypass, and bowel perforation complicated by extensive resection and short gut syndrome, as well as rheumatoid arthritis and chronic kidney disease, presented to clinic for intermittent right upper quadrant pain, nausea, and vomiting. Imaging revealed large cholelithiasis, choledocholithiasis, and biliary dilatation with gallbladder distention. Given his high surgical risk and symptomatic biliary disease, EDGE and EUS-guided management of the large gallstone was planned. The first step was to create a jejunogastrostomy (JG) which was performed using EUS-guided 15mmx10mm lumen-apposing metal stent (LAMS) deployment through the Roux limb into the excluded stomach. ERCP was performed 4 weeks later finding choledocholithiasis, and complete removal of two stones was accomplished. This was followed by EUS-guided gallbladder drainage via JG and successful creation of a cholecystoduodenostomy (CDS) using the 15mmx10mm AXIOS stent system. Direct cholecystoscopy, electrohydraulic lithotripsy and removal of a large gallstone were then performed. Both LAMS from JG and CDS were removed at the end of the procedure. Follow-up upper GI series at 6 weeks showed complete closure of the jejunogastrostomy fistula. Discussion: The EDGE approach provides access to the excluded remnant stomach enabling ERCP and interventional EUS procedures such as gall bladder drainage. In this case, we demonstrate the utility of this procedure in enabling access to the gallbladder and permitting direct cholecystoscopy, electrohydraulic lithotripsy, and removal of a large symptomatic gallstone, thus avoiding long-term percutaneous drains and recurrent symptoms, in addition to the risk of cholecystitis or Mirizzi syndrome from a large gallstone. Watch the video at https://tinyurl.com/ACGAbstractS348

Measurement of the anchoring force of covered self-expandable and lumen-apposing metal stents for interventional endoscopic ultrasonography.

Interventional endoscopic ultrasonography is performed for various situations that require drainage, after which stent migration is the most severe adverse event. Several lumen-apposing metal stents (LAMS) and covered self-expandable metal stents (CSEMS) provide antimigration systems; however, their anchoring ability has not been studied well. Therefore, we measured and compared the anchoring force (ACF) of commercially available LAMS and CSEMS. Anchoring force was measured for five types of LAMS (NAGI, SPAXUS, Plumber, and AXIOS 8 and 10 mm) and seven types of CSEMS (BCL, SHCL, BCG, BPD [four types of HANAROSTENT], HILZO, Niti-S [Spring Stopper], and Wallflex). We created a phantom model for inducing stent migration. It has a rotatable part as a curved fixture, and we measured ACF at angles between 0° and 40°. The mean ACF at 0° and 20° were NAGI 1.50, 1.84 N, SPAXUS 1.73, 1.72 N, Plumber 2.64, 2.03 N, and AXIOS 3.96, 3.61 N, respectively; and BCL 0.48, 0.53 N, Wallflex 0.53, 0.48 N, SHCL 0.64, 0.73 N, HILZO 1.09, 1.09 N, BCG 1.22, 1.20 N, BPD 1.78, 1.67 N, and Spring Stopper 2.29, 2.51 N. We measured ACF in LAMS and CSEMS with a new phantom model. The highest value among the LAMS was for the AXIOS and among the CSEMS was for the Spring Stopper. Some of the ACF values varied with the direction of pull. These findings may have a significant impact on stent selection for interventional endoscopic ultrasonography, and this model can be used to evaluate newly developed stents.

The Role of Endoscopic Ultrasound in the Interventional Management of Mediastinal Collections: A Narrative Review.

The numerous causes underlying mediastinal lesions require different diagnostic and therapeutic approaches, including conservative, minimally invasive, and surgical interventions. Solid lesions of a malignant nature, mostly located in the anterior mediastinum, are properly treated with surgical resection either with or without adjuvant schemes. In contrast, a surveillance program is usually recommended with solid benign tumors, depending on their size and related symptomatology. In the management of mediastinal collections, when a drainage intervention is required (suspicion of infection and symptomatology), a minimally invasive nonsurgical procedure or thoracic surgery is considered. The minimally invasive nonsurgical procedures that can be available are percutaneous radiology-guided imaging (abdominal ultrasound (US) or computed tomography (CT) scan), complete single-aspiration guided by endoscopic ultrasound (EUS) or endobronchial ultrasound (EBUS), and transmural drainage guided by EUS. Surgical debridement is feasible to treat collections, but as this entails considerable risk of postoperative complications, it is chosen only when other minimally invasive therapies are not possible. The published literature related to the interventional endoscopic approach to mediastinal lesions is scarce. Nevertheless, reports in this field reveal that interventional EUS may have a role in both the diagnosis of and therapeutic approach to mediastinal lesions, mainly in the management of mediastinal collections.

Driving Quality in Advanced Endoscopy

Interventional endoscopy (IE) has undergone a remarkable transformation over the past 2 decades, expanding from hemostasis, endoscopic retrograde cholangiopancreatography, polypectomy, and diagnostic endoscopic ultrasound (EUS) to numerous areas, such as endoscopic eradication therapy for Barrett’s esophagus, interventional EUS, bariatric endoscopy, and “third-space” endoscopy. As these procedures are refined, it is critical that quality metrics with respect to procedural training, technique, and follow-up are developed, similar to those of more commonly performed endoscopic procedures.

Endoscopic ultrasound in diagnosis and management of some gastrointestinal - pancreaticobiliary diseases at Hue University of Medicine and Pharmacy Hospital

Background: Gastrointestinal - pancreaticobiliary diseases is a major pathology relating to organs from the mouth to the anus and biliary tree. Endoscopic ultrasound (EUS) helps to assess deeper organs in the abdomen such as pancreas, biliary tree, lesions inside and outside the alimentary tract as well as regional lymph nodes. We proceeded this study to: (1) To examine some characteristics of patients, indications and safety of EUS, (2) To evaluate roles of EUS in diagnosis and management of gastrointestinal - pancreaticobiliary diseases. Materials and method: A cross-sectional study was conducted on 1615 patients undergoing endoscopic ultrasound at Hue University of Medicine and Pharmacy Hospital. Results: Male:female ratio = 1.4:1. Average age was 56.1 ± 15.1. Patients living in Hue was 79.9%, not living in Hue was 20.1%. Indications of EUS: in biliary diseases 37.1%, in pancreatic diseases 31.3%, in stomach 11.8%, in colon 9.0%, in esophagus 8.6%, and in duodenum 2.2%. Complications rates were very low. Lesions in gastrointestinal tract: Subepithelial lesions in stomach 57.9%, in esophagus 23.7%, in duodenum 13.6%, in colo-rectum 4.8%; cancer in colo-rectum 48.8%, in esophagus 33.2%, in stomach 16.3%, and in duodenum 1.7%. Lesions in biliary tree: gallstones 76%, common bile duct cyst 9.5%, bile duct parasitic lesions 4.3%, Vater tumor 3.8%, unknown causes biliary tract dilation 3.4% and cholangiocarcinoma 3.0%. Lesions in pancreas: chronic pancreatitis40.6%, pancreatic cancer 24.6%, acute pancreatitis 18.4%, pancreatic cyst 10.9% and lymph nodes 5.5%. EUSfine needle aspiration and EUS-guided drainage of pancreatic pseudocysts: FNA for 18 pancreatic tumors, 3 pancreatic cysts and 7 lymph nodes; drainage for 4 pancreatic pseudocysts. Conclusions: Diagnostic and interventional EUS were effectively and relatively safe in assessing lesions in alimentary tract and biliary diseases, as well as supporting to achieve samples through fine needle aspiration, and to drain pancreatic pseudocysts. Key words: endoscopy, endosonography

Evaluation of an all-in-one hybrid model (EUS Magic Box) for stepwise teaching and training in multiple interventional EUS procedures.

Background and study aims  While multiple interventional endoscopic ultrasound (EUS)-guided procedures have evolved over the past two decades, there is no model that allows for training in all of these procedures. We aimed to develop and validate an all-in-one hybrid model for stepwise learning in multiple EUS interventions. Methods  A hybrid model was created utilizing a pig esophagus and stomach, a silicon-based duodenum and pancreato-biliary system, a pseudocyst, and biopsy targets. This model was designed to provide hands-on training in multiple interventional EUS procedures, such as EUS-guided fine-needle biopsy (EUS-FNB), biliary drainage (BD), pancreatic duct drainage (PD), pseudocyst drainage (PSD), and gastro-enterostomy (GE). Thirty-six trainees underwent training on this model over 6 days, in two batches. Lumen apposing metal stents were used for PSD and GE. Trainees were assessed for objective criteria of technical difficulties. Subjective assessment by trainees was done via a questionnaire. Results  All the trainees were able to complete the requisite steps for all the procedures under supervision. On subjective assessment, 30 trainees (83 %) graded the model as good or excellent. A total of 107 technical difficulties were noted (scope position 55, duct puncture 27, guidewire-related problems 25). Time taken to complete the requisite steps of biopsy, PSD, and GE (10.5 minutes; range 3.5 to 22) was significantly less than that for BD and PD (28 minutes; range 17 to 40) ( P  < 0.001). Conclusions  The hybrid model provided training for multiple EUS interventions with good acceptance by trainees. Stepwise mentoring with the possibility of performing multiple procedures in a single model with or without X-ray could prove useful in conference as well as institutional settings.

Experimental study of a physician-controlled electrocautery-enhanced delivery system incorporating a newly developed lumen-apposing metal stent for interventional endoscopic ultrasound (with videos).

Although the lumen-apposing metal stent (LAMS) is useful for interventional endoscopic ultrasound (EUS) procedures, there has been some concern about the potential for stent-induced adverse events because of the high lumen-apposing force. A newly designed LAMS with less lumen-apposing force has been developed for use with a physician-controlled electrocautery-enhanced delivery system. The aim of this animal study was to evaluate the feasibility of performing interventional EUS using this newly designed LAMS system. Endoscopic ultrasound-guided cystogastrostomy was performed using the novel LAMS three times in a wet simulation model. EUS-guided gastroenterostomy and EUS-guided gallbladder drainage were then performed using the system in four pigs. The LAMS was successfully placed in all three EUS-guided cystogastrostomy procedures using the wet simulation model and in all four EUS-guided gastroenterostomy and gallbladder drainage procedures in the animal model. In the 3weeks following the procedure, eating behavior was normal in all animals and there were no adverse events. The stents remained patent during this time and were removed without difficulty. The fistula was mature in all cases and a standard upper gastrointestinal endoscope was easily advanced via the fistula to observe the afferent and efferent loops or the lumen of the gallbladder. Necropsy confirmed complete adhesion between the stomach and the wall of the jejunum or gallbladder. Our study findings demonstrate the feasibility of this new LAMS system and its potential clinical value for interventional EUS.

Endoscopic ultrasound role in pancreatic adenocarcinoma treatment: A review focusing on technical success, safety and efficacy.

The impressive technological advances in recent years have rapidly translated into the shift of endoscopic ultrasound (EUS) from diagnostic modality into an interventional and therapeutic tool. Despite the great advance in its diagnosis, the majority of pancreatic adenocarcinoma cases are inoperable when diagnosed, thus demanding alternative optional therapies. EUS has emerged as an easy, minimally invasive modality targeting this carcinoma with different interventions that have been reported recently. In this review we summarize the evolving role of interventional therapeutic EUS in pancreatic adenocarcinoma management.

Current role of endoscopic ultrasound in the diagnosis and management of pancreatic cancer.

Endoscopic ultrasound (EUS) has emerged as an invaluable tool for the diagnosis, staging and treatment of pancreatic ductal adenocarcinoma (PDAC). EUS is currently the most sensitive imaging tool for the detection of solid pancreatic tumors. Conventional EUS has evolved, and new imaging techniques, such as contrast-enhanced harmonics and elastography, have been developed to improve diagnostic accuracy during the evaluation of focal pancreatic lesions. More recently, evaluation with artificial intelligence has shown promising results to overcome operator-related flaws during EUS imaging evaluation. Currently, an appropriate diagnosis is based on a proper histological assessment, and EUS-guided tissue acquisition is the standard procedure for pancreatic sampling. Newly developed cutting needles with core tissue procurement provide the possibility of molecular evaluation for personalized oncological treatment. Interventional EUS has modified the therapeutic approach, primarily for advanced pancreatic cancer. EUS-guided fiducial placement for local targeted radiotherapy treatment or EUS-guided radiofrequency ablation has been developed for local treatment, especially for patients with pancreatic cancer not suitable for surgical resection. Additionally, EUS-guided therapeutic procedures, such as celiac plexus neurolysis for pain control and EUS-guided biliary drainage for biliary obstruction, have dramatically improved in recent years toward a more effective and less invasive procedure to palliate complications related to PDAC. All the current benefits of EUS in the diagnosis and management of PDAC will be thoroughly discussed.

Diagnostic Reference Levels for Fluoroscopy-guided Gastrointestinal Procedures in Japan from the REX-GI Study: A Nationwide Multicentre Prospective Observational Study

SummaryBackgroundDiagnostic reference levels (DRLs) are required to optimize medical exposure. However, data on DRLs for interventional fluoroscopic procedures are lacking, especially in gastroenterology. This study aimed to prospectively collect currently used radiation doses and help establish national DRLs for fluoroscopy-guided gastrointestinal procedures in Japan.MethodsThis multicentre, prospective, observational study collected actual radiation dose data from endoscopic retrograde cholangiopancreatography (ERCP), interventional endoscopic ultrasound (EUS), balloon-assisted enteroscopy (BAE), enteral metallic stent placement, and enteral tube placement from May 2019 to December 2020. The study outcomes were fluoroscopy time (FT: min), air kerma at the patient entrance reference point (Ka,r: mGy), air kerma area product (PKA: Gycm2), and radiation dose rate (RDR: mGy/min). Additionally, the basic settings of fluoroscopy equipment and the factors related to each procedure were investigated. This study was registered in the UMIN Clinical Trial Registry (UMIN 000036525).FindingsOverall, 12959 fluoroscopy-guided gastrointestinal procedures were included from 23 hospitals in Japan. For 11162 ERCPs, the median/third quartile values of Ka,r (mGy), PKA (Gycm2), and FT (min) were 69/145 mGy, 16/32 Gycm2, and 11/20 min, respectively. Similarly, these values were 106/219 mGy, 23/41 Gycm2 and 17/27 min for 374 interventional EUSs; 53/104 mGy, 16/32 Gycm2 and 10/15 min for 523 metallic stents; 56/104 mGy, 28/47 Gycm2, and 12/18 min for 599 tube placements; and 35/81 mGy, 16/43 Gycm2 and 7/15 min for 301 BAEs, respectively. For the overall radiation dose rate, the median/third quartile values of RDR were 5.9/9.4 (mGy/min). The RDR values at each institution varied widely.InterpretationThis study reports the current radiation doses of fluoroscopy-guided gastrointestinal procedures expressed as DRL quantities. This will serve as a valuable reference for national DRL values.FundingThis work was supported by a clinical research grant from the Japanese Society of Gastroenterology.

Endoscopic Ultrasonography-Specific Stents

AbstractThe evolution of the endoscopic ultrasonography (EUS) technique has necessitated the development of EUS-specific accessories and stents. In the earlier period, EUS-guided interventions mostly relied on borrowed accessories and stents from therapeutic endoscopy in particular ERCP. Traditional stents do not serve the purpose of EUS-guided transluminal stenting in all cases due to the length of the stent, no anchoring mechanism, and chance of migration. From 2011 onward, several EUS-specific stents became available, bringing a paradigm shift in interventional EUS. This article reviews current EUS-specific stents, indications, strengths, and weaknesses.