Endoscopic ultrasound: Current roles and future directions

Spinal tissue identification using a Forward-oriented endoscopic ultrasound technique

The limited imaging depth of optical endoscope restrains the identification of tissues under surface during the minimally invasive spine surgery (MISS), thus increasing the risk of critical tissue damage. This study is proposed to improve the accuracy and effectiveness of automatic spinal soft tissue identification using a forward-oriented ultrasound endoscopic system. Total 758 ex-vivo soft tissue samples were collected from ovine spines to create a dataset with four categories including spinal cord, nucleus pulposus, adipose tissue, and nerve root. Three conventional methods including Gray-level co-occurrence matrix (GLCM), Empirical Wavelet Transform (EWT), Variational Mode Decomposition (VMD) and two deep-learning based methods including Densely Connected Neural Network (DenseNet) model, one-dimensional Vision Transformer (ViT) model, were applied to identify the spinal tissues. The two deep learning methods outperformed the conventional methods with both accuracy over 95%. Especially the signal-based method (ViT) achieved an accuracy of 98.31% and a specificity of 99.2%, and the inference latency was only 0.0025 s. It illustrated the feasibility of applying the forward-oriented ultrasound endoscopic system for real-time intraoperative recognition of critical spinal tissues to enhance the precision and safety of minimally invasive spine surgery.

Validity evidence for endoscopic ultrasound competency assessment tools: Systematic review

Background and study aims Competent endoscopic ultrasound (EUS) performance requires a combination of technical, cognitive, and non-technical skills. Direct observation assessment tools can be employed to enhance learning and ascertain clinical competence; however, there is a need to systematically evaluate validity evidence supporting their use. We aimed to evaluate the validity evidence of competency assessment tools for EUS and examine their educational utility. Methods We systematically searched five databases and gray literature for studies investigating EUS competency assessment tools from inception to May 2023. Data on validity evidence across five domains (content, response process, internal structure, relations to other variables, and consequences) were extracted and graded (maximum score 15). We evaluated educational utility using the Accreditation Council for Graduate Medical Education framework and methodological quality using the Medical Education Research Quality Instrument (MERSQI). Results From 2081 records, we identified five EUS assessment tools from 10 studies. All tools are formative assessments intended to guide learning, with four employed in clinical settings. Validity evidence scores ranged from 3 to 12. The EUS and ERCP Skills Assessment Tool (TEESAT), Global Assessment of Performance and Skills in EUS (GAPS-EUS), and the EUS Assessment Tool (EUSAT) had the strongest validity evidence with scores of 12, 10, and 10, respectively. Overall educational utility was high given ease of tool use. MERSQI scores ranged from 9.5 to 12 (maximum score 13.5). Conclusions The TEESAT, GAPS-EUS, and EUSAT demonstrate strong validity evidence for formative assessment of EUS and are easily implemented in educational settings to monitor progress and support learning.

Linear endoscopic ultrasound: Current uses and future perspectives in mediastinal examination

This editorial elaborates on the current and future applications of linear endoscopic ultrasound (EUS), a substantial diagnostic and therapeutic modality for various anatomical regions. The scope of endosonographic assessment is broad and, among other factors, allows for the evaluation of the mediastinal anatomy and related pathologies, such as mediastinal lymphadenopathy and the staging of central malignant lung lesions. Moreover, EUS assessment has proven more accurate in detecting small lesions missed by standard imaging examinations, such as computed tomography or magnetic resonance imaging. We focus on its current uses in the mediastinum, including lung and esophageal cancer staging, as well as evaluating mediastinal lymphadenopathy and submucosal lesions. The editorial also explores future perspectives of EUS in mediastinal examination, including ultrasound-guided therapies, artificial intelligence integration, advancements in mediastinal modalities, and improved diagnostic approaches for various mediastinal lesions.

Utility of Endoscopic Ultrasound-Guided Fine-Needle Aspiration in a Paediatric Population: A Single-Centre Experience

INTRODUCTION

Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) is a modern and minimally invasive technique to acquire diagnostic material from within the gastrointestinal tract, as well as from adjacent organs and structures, which can help in the diagnosis and staging of a variety of gastrointestinal malignancies, as well as for non-malignant conditions. Though well described in adults, there is limited literature on the diagnostic utility of EUS-FNA in paediatric patients. The objective of this study was to evaluate the diagnostic accuracy and clinical utility of EUS-FNA in paediatric patients performed at our centre over the last 17 years.

MATERIALS AND METHODS

After obtaining Institutional Review Board approval, 63 cases of paediatric EUS-FNA performed at SKMCH&RC from 2005 to 2022 were retrieved. A 22-gauge EUS-FNA needle was used for obtaining samples with the use of suction (when required). The sample was then smeared onto glass slides, with half being stained with RAPI stain while the rest with the Papanicolaou stain. Demographic details, indication for the procedure, results of rapid on-site adequacy status (ROSE), site of lesion, and cytological diagnosis were reviewed and analysed.

RESULTS

Of the 63 patients, 55 (87.3%) had an adequate sample (confirmed on ROSE). Forty-two (66.7%) were male and the mean age was 12.4 years. The most frequent indication of EUS-FNA was a sampling of enlarged lymph nodes (74.6%). The most common sites of nodal aspiration were sub-carinal (33.3%) and celiac lymph nodes (14.3%). EUS-FNA of a pancreatic lesion accounted for an additional 17.5% of cases. Involvement by Hodgkin's lymphoma was the most common diagnosis (25.4%) followed by granulomatous inflammation (19.1%). Cases of solid pseudo-papillary tumour (4.8%) and recurrent Wilm's tumour (3.2%) were also diagnosed. No patient suffered complications, and none required hospital admission, post-procedure. The sensitivity, specificity, PPV, and NPV of EUS-FNA were 98.1, 83.3, 96.4, and 90.9%, respectively.

CONCLUSION

EUS-FNA is a safe, well-tolerated, minimally invasive outpatient setting procedure with high sensitivity and significant utility in the diagnosis and staging of disease.

Endoscopic Ultrasonography In Diagnostic Endohepatology: The Hepatologist's Swiss Army Knife

In recent years, significant advances have been made in endoscopic ultrasonography (EUS) processors, transducers, and the instruments used. In parallel with these developments, the importance of EUS in the diagnosis, treatment, and management of chronic liver diseases has increased considerably. One of the most important advantages of EUS is that the ultrasound probe can examine the liver area under examination from a very close distance. Additionally, EUS provides the ability to provide excellent spatial files and realtime images; Doppler, elastography, and contrast methods are also widely used to increase diagnostic accuracy in EUS evaluations. Endoscopic ultrasound-guided procedures are an alternative method used when percutaneous approaches are not feasible. Endoscopic ultrasound-based advanced applications such as EUSguided liver biopsy (LB), EUS-guided ascites assessment, the use of EUS in the evaluation of focal lesions of the liver, and EUS portal pressure gradient (EUS-PPG) measurements are becoming increasingly common and important. As a result of the developments in EUS devices and instruments, it is possible to perform all diagnostic procedures in hepatology with EUS. In other words, EUS can provide all the imaging and interventional procedures that a hepatologist would require for diagnosis in a single session, without the need for any other expertise other than the gastroenterologist (such as a radiologist, interventional radiologist, or surgeon). This is called the single-procedure diagnostic approach, or "all in one" in hepatology. From a hepatologist's perspective, EUS can be thought of as the "hepatologist's Swiss army knife."

A Comprehensive Guide to Artificial Intelligence in Endoscopic Ultrasound

BACKGROUND

Endoscopic Ultrasound (EUS) is widely used for the diagnosis of bilio-pancreatic and gastrointestinal (GI) tract diseases, for the evaluation of subepithelial lesions, and for sampling of lymph nodes and solid masses located next to the GI tract. The role of Artificial Intelligence in healthcare in growing. This review aimed to provide an overview of the current state of AI in EUS from imaging to pathological diagnosis and training.

METHODS

AI algorithms can assist in lesion detection and characterization in EUS by analyzing EUS images and identifying suspicious areas that may require further clinical evaluation or biopsy sampling. Deep learning techniques, such as convolutional neural networks (CNNs), have shown great potential for tumor identification and subepithelial lesion (SEL) evaluation by extracting important features from EUS images and using them to classify or segment the images.

RESULTS

AI models with new features can increase the accuracy of diagnoses, provide faster diagnoses, identify subtle differences in disease presentation that may be missed by human eyes, and provide more information and insights into disease pathology.

CONCLUSIONS

The integration of AI in EUS images and biopsies has the potential to improve the diagnostic accuracy, leading to better patient outcomes and to a reduction in repeated procedures in case of non-diagnostic biopsies.

The Role of Endoscopic Ultrasound in Hepatology

Endoscopic ultrasound (EUS) has been an indispensable and widely used diagnostic tool in several medical fields, including gastroenterology, cardiology, and urology, due to its diverse therapeutic and diagnostic applications. Many studies show that it is effective and safe in patients with liver conditions where conventional endoscopy or cross-sectional imaging are inefficient or when surgical interventions pose high risks. In this article, we present a review of the current literature for the different diagnostic and therapeutic applications of EUS in liver diseases and their complications and discuss the potential future application of artificial intelligence analysis of EUS.

Role of interventional endoscopic ultrasound in a developing country

BACKGROUND/AIMS

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.

METHODS

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.

RESULTS

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.

CONCLUSION

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.

Role of Endoscopy in Management of Upper Gastrointestinal Cancers

Upper gastrointestinal (GI) malignancy is a leading cause of cancer-related morbidity and mortality. Upper endoscopy has an established role in diagnosing and staging upper GI cancers, screening for pre-malignant lesions, and providing palliation in cases of advanced malignancy. New advances in endoscopic techniques and technology have improved diagnostic accuracy and increased the therapeutic potential of upper endoscopy. We aim to describe the different types of endoscopic technology used in cancer diagnosis, summarize the current guidelines for endoscopic diagnosis and treatment of malignant and pre-malignant lesions, and explore new potential roles for endoscopy in cancer therapy.

Neuroendocrine Tumor Diagnosed Through Endoscopic Ultrasound-Guided Fine-Needle Biopsy of a Lung Mass

Endoscopic ultrasound-guided fine-needle biopsy (EUS-FNB) is an excellent modality for tissue acquisition and has been shown to be superior to EUS-fine-needle aspiration in several studies. Although tissue sampling of lung nodules using EUS-fine-needle aspiration has been reported in the literature, the use of EUS-FNB for tissue acquisition of parenchymal lung mass has rarely been reported in the literature. Our report highlights that EUS-FNB is safe and effective for lung lesions that are near the esophageal wall.

Analysis of Decreasing Adverse Events with Endoscopic Ultrasound in a New Advanced Endoscopy Program Over Time

OBJECTIVE

New innovations and increasing utility of endoscopic ultrasound (EUS) are associated with rare but serious risks. We investigate the rates and risk factors for post-procedural complications over a four-year period at a new advanced endoscopy program.

METHODS

We conducted a retrospective review of all adult patients who underwent upper EUS at an academic level-1 trauma center between April 2015 and November 2019. The primary outcome was the incidence of adverse events within 1 week of EUS. Secondary outcomes included emergency department visits and mortality within 30 days after EUS. Chi-square test, t test, and multivariable logistic regression were used to assess risk factors for post-procedural complications.

RESULTS

A total of 968 EUS procedures were performed on 864 patients (54% female; 79% Caucasian; mean age 61 years). The overall incidence of post-procedural adverse event with EUS was 5.6%. The probability of an adverse event decreased by an average of 22% per year (p =0.01, OR 0.78). The risk for adverse events were 3.3% acute pancreatitis, 1.9% clinically significant bleeding, 0.3% bacteremia, 0.2% perforation, and 2.4% 30-day mortality. The adverse event rate was highest among low volume proceduralists (p =0.04). The 30-day mortality was more than threefolds among patients who had an adverse event within 7 days after EUS.

CONCLUSION

The overall incidence of post-procedural adverse events at a new EUS program was 5.6%, with an average of 22% relative decrease in adverse events per year in the first 4 years.

Role of endoscopic ultrasound in the field of hepatology: Recent advances and future trends

The role of endoscopic ultrasound (EUS) as a diagnostic and therapeutic modality for the management of various gastrointestinal diseases has been expanding. The imaging or intervention for various liver diseases has primarily been the domain of radiologists. With the advances in EUS, the domain of endosonologists is rapidly expanding in the field of hepatology. The ability to combine endoscopy and sonography in one hybrid device is a unique property of EUS, together with the ability to bring its probe/transducer near the liver, the area of interest. Its excellent spatial resolution and ability to provide real-time images coupled with several enhancement techniques, such as contrast-enhanced (CE) EUS, have facilitated the growth of EUS. The concept of “Endo-hepatology” encompasses the wide range of diagnostic and therapeutic procedures that are now gradually becoming feasible for managing various liver diseases. Diagnostic advancements can enable a wide array of techniques from elastography and liver biopsy for liver parenchymal diseases, to CE-EUS for focal liver lesions to portal pressure measurements for managing various liver conditions. Similarly, therapeutic advancements range from EUS-guided eradication of varices, drainage of bilomas and abscesses to various EUS-guided modalities of liver tumor management. We provide a comprehensive review of all the different diagnostic and therapeutic EUS modalities available for the management of various liver diseases. A synopsis of all the technical details involving each procedure and the available data has been tabulated, and the future trends in this area have been highlighted.

Endoscopic ultrasound-guided vascular interventions: Current insights and emerging techniques

Endoscopic ultrasound (EUS) is one of the significant breakthroughs in the field of advanced endoscopy. In the last two decades, EUS has evolved from a diagnostic tool to a real-time therapeutic modality. The luminal gastrointestinal (GI) tract provides a unique opportunity to access multiple vascular structures, especially in the mediastinum and abdomen, thus permitting a variety of EUS-guided vascular interventions. The addition of the doppler and contrast-enhanced capability to EUS has further helped provide real-time visualization of blood flow in vessels through the GI tract. EUS-guided vascular interventions rely on standard endoscopic accessories and interventional tools such as fine-needle aspiration needles and fine-needle biopsy. EUS allows the visualization of various structures in real-time by differentiating tissue densities and vascularity, thus, avoiding radiation exposure. EUS-guided techniques also allow real-time microscopic examination after target biopsy. Furthermore, many necessary interventions can be done during the same procedure after diagnosis. This article provides an overview of EUS-guided vascular interventions such as variceal, non-variceal bleeding interventions, EUSguided portal vein (PV) access with the formation of an intrahepatic portosystemic shunt, and techniques related to diagnosis of GI malignancies. Furthermore, we discuss current insights and future outlook of therapeutic modalities like PV embolization, PV sampling, angiography, drug administration, and portal pressure measurement.

Endoscopic ultrasound-guided vascular interventions: Current insights and emerging techniques

Endoscopic ultrasound (EUS) is one of the significant breakthroughs in the field of advanced endoscopy. In the last two decades, EUS has evolved from a diagnostic tool to a real-time therapeutic modality. The luminal gastrointestinal (GI) tract provides a unique opportunity to access multiple vascular structures, especially in the mediastinum and abdomen, thus permitting a variety of EUS-guided vascular interventions. The addition of the doppler and contrast-enhanced capability to EUS has further helped provide real-time visualization of blood flow in vessels through the GI tract. EUS-guided vascular interventions rely on standard endoscopic accessories and interventional tools such as fine-needle aspiration needles and fine-needle biopsy. EUS allows the visualization of various structures in real-time by differentiating tissue densities and vascularity, thus, avoiding radiation exposure. EUS-guided techniques also allow real-time microscopic examination after target biopsy. Furthermore, many necessary interventions can be done during the same procedure after diagnosis. This article provides an overview of EUS-guided vascular interventions such as variceal, non-variceal bleeding interventions, EUSguided portal vein (PV) access with the formation of an intrahepatic portosystemic shunt, and techniques related to diagnosis of GI malignancies. Furthermore, we discuss current insights and future outlook of therapeutic modalities like PV embolization, PV sampling, angiography, drug administration, and portal pressure measurement.

Endoscopic ultrasound-guided vascular interventions: Current insights and emerging techniques

Endoscopic ultrasound (EUS) is one of the significant breakthroughs in the field of advanced endoscopy. In the last two decades, EUS has evolved from a diagnostic tool to a real-time therapeutic modality. The luminal gastrointestinal (GI) tract provides a unique opportunity to access multiple vascular structures, especially in the mediastinum and abdomen, thus permitting a variety of EUS-guided vascular interventions. The addition of the doppler and contrast-enhanced capability to EUS has further helped provide real-time visualization of blood flow in vessels through the GI tract. EUS-guided vascular interventions rely on standard endoscopic accessories and interventional tools such as fine-needle aspiration needles and fine-needle biopsy. EUS allows the visualization of various structures in real-time by differentiating tissue densities and vascularity, thus, avoiding radiation exposure. EUS-guided techniques also allow real-time microscopic examination after target biopsy. Furthermore, many necessary interventions can be done during the same procedure after diagnosis. This article provides an overview of EUS-guided vascular interventions such as variceal, non-variceal bleeding interventions, EUSguided portal vein (PV) access with the formation of an intrahepatic portosystemic shunt, and techniques related to diagnosis of GI malignancies. Furthermore, we discuss current insights and future outlook of therapeutic modalities like PV embolization, PV sampling, angiography, drug administration, and portal pressure measurement.

Endoscopic ultrasound-guided vascular interventions: Current insights and emerging techniques

Endoscopic ultrasound (EUS) is one of the significant breakthroughs in the field of advanced endoscopy. In the last two decades, EUS has evolved from a diagnostic tool to a real-time therapeutic modality. The luminal gastrointestinal (GI) tract provides a unique opportunity to access multiple vascular structures, especially in the mediastinum and abdomen, thus permitting a variety of EUS-guided vascular interventions. The addition of the doppler and contrast-enhanced capability to EUS has further helped provide real-time visualization of blood flow in vessels through the GI tract. EUS-guided vascular interventions rely on standard endoscopic accessories and interventional tools such as fine-needle aspiration needles and fine-needle biopsy. EUS allows the visualization of various structures in real-time by differentiating tissue densities and vascularity, thus, avoiding radiation exposure. EUS-guided techniques also allow real-time microscopic examination after target biopsy. Furthermore, many necessary interventions can be done during the same procedure after diagnosis. This article provides an overview of EUS-guided vascular interventions such as variceal, non-variceal bleeding interventions, EUSguided portal vein (PV) access with the formation of an intrahepatic portosystemic shunt, and techniques related to diagnosis of GI malignancies. Furthermore, we discuss current insights and future outlook of therapeutic modalities like PV embolization, PV sampling, angiography, drug administration, and portal pressure measurement.

Endoscopic ultrasound-guided vascular interventions: Current insights and emerging techniques

Endoscopic ultrasound (EUS) is one of the significant breakthroughs in the field of advanced endoscopy. In the last two decades, EUS has evolved from a diagnostic tool to a real-time therapeutic modality. The luminal gastrointestinal (GI) tract provides a unique opportunity to access multiple vascular structures, especially in the mediastinum and abdomen, thus permitting a variety of EUS-guided vascular interventions. The addition of the doppler and contrast-enhanced capability to EUS has further helped provide real-time visualization of blood flow in vessels through the GI tract. EUS-guided vascular interventions rely on standard endoscopic accessories and interventional tools such as fine-needle aspiration needles and fine-needle biopsy. EUS allows the visualization of various structures in real-time by differentiating tissue densities and vascularity, thus, avoiding radiation exposure. EUS-guided techniques also allow real-time microscopic examination after target biopsy. Furthermore, many necessary interventions can be done during the same procedure after diagnosis. This article provides an overview of EUS-guided vascular interventions such as variceal, non-variceal bleeding interventions, EUSguided portal vein (PV) access with the formation of an intrahepatic portosystemic shunt, and techniques related to diagnosis of GI malignancies. Furthermore, we discuss current insights and future outlook of therapeutic modalities like PV embolization, PV sampling, angiography, drug administration, and portal pressure measurement.

Endoscopic ultrasound-guided vascular interventions: Current insights and emerging techniques

Endoscopic ultrasound (EUS) is one of the significant breakthroughs in the field of advanced endoscopy. In the last two decades, EUS has evolved from a diagnostic tool to a real-time therapeutic modality. The luminal gastrointestinal (GI) tract provides a unique opportunity to access multiple vascular structures, especially in the mediastinum and abdomen, thus permitting a variety of EUS-guided vascular interventions. The addition of the doppler and contrast-enhanced capability to EUS has further helped provide real-time visualization of blood flow in vessels through the GI tract. EUS-guided vascular interventions rely on standard endoscopic accessories and interventional tools such as fine-needle aspiration needles and fine-needle biopsy. EUS allows the visualization of various structures in real-time by differentiating tissue densities and vascularity, thus, avoiding radiation exposure. EUS-guided techniques also allow real-time microscopic examination after target biopsy. Furthermore, many necessary interventions can be done during the same procedure after diagnosis. This article provides an overview of EUS-guided vascular interventions such as variceal, non-variceal bleeding interventions, EUSguided portal vein (PV) access with the formation of an intrahepatic portosystemic shunt, and techniques related to diagnosis of GI malignancies. Furthermore, we discuss current insights and future outlook of therapeutic modalities like PV embolization, PV sampling, angiography, drug administration, and portal pressure measurement.

Speckle reduction in ultrasound endoscopy using refraction based elevational angular compounding

Endoscopic ultrasonography (EUS) is a safe, real-time diagnostic and therapeutic tool. Speckle noise, inherent to ultrasonography, degrades the diagnostic precision of EUS. Elevational angular compounding (EAC) can provide real-time speckle noise reduction; however, EAC has never been applied to EUS because current implementations require costly and bulky arrays and are incompatible with the tight spatial constraints of hollow organs. Here we develop a radial implementation of a refraction-based elevational angular compounding technique (REACT) for EUS and demonstrate for the first time spatial compounding in a radial endoscopy. The proposed implementation was investigated in cylindrical phantoms and demonstrated superior suppression of ultrasound speckle noise and up to a two-fold improvement in signal- and contrast- ratios, compared to standard image processing techniques and averaging. The effect of elevational angular deflection on image fidelity was further investigated in a phantom with lymph node-like structures to determine the optimum elevational angular width for high speckle reduction efficiency while maintaining image fidelity. This study introduces REACT as a potential compact and low-cost solution to impart current radial echo-endoscopes with spatial compounding, which could enable accurate identification and precise sizing of lymph nodes in staging of gastrointestinal tract cancers.

Accuracy of clinical staging for T2N0 oesophageal cancer: systematic review and meta-analysis

Oesophageal cancer is the sixth commonest cause of overall cancer mortality. Clinical staging utilizes multiple imaging modalities to guide treatment and prognostication. T2N0 oesophageal cancer is a treatment threshold for neoadjuvant therapy. Data on accuracy of current clinical staging tests for this disease subgroup are conflicting. We performed a meta-analysis of all primary studies comparing clinical staging accuracy using multiple imaging modalities (index test) to histopathological staging following oesophagectomy (reference standard) in T2N0 oesophageal cancer. Patients that underwent neoadjuvant therapy were excluded. Electronic databases (MEDLINE, Embase, Cochrane Library) were searched up to September 2019. The primary outcome was diagnostic accuracy of combined T&N clinical staging. Publication date, first recruitment date, number of centers, sample size and geographical location main histological subtype were evaluated as potential sources of heterogeneity. The search strategy identified 1,199 studies. Twenty studies containing 5,213 patients met the inclusion criteria. Combined T&N staging accuracy was 19% (95% CI, 15-24); T staging accuracy was 29% (95% CI, 24-35); percentage of patients with T downstaging was 41% (95% CI, 33-50); percentage of patients with T upstaging was 28% (95% CI, 24-32) and percentage of patients with N upstaging was 34% (95% CI, 30-39). Significant sources of heterogeneity included the number of centers, sample size and study region. T2N0 oesophageal cancer staging remains inaccurate. A significant proportion of patients were downstaged (could have received endotherapy) or upstaged (should have received neoadjuvant chemotherapy). These findings were largely unchanged over the past two decades highlighting an urgent need for more accurate staging tests for this subgroup of patients.

Contrast-enhanced endoscopic ultrasound features of tubercular lymphadenopathy

There is lack of data on the contrast-enhanced endoscopic ultrasound features of tubercular lymph node; our retrospective analysis of 37 patients with enlarged mediastinal and abdominal lymph nodes showed heterogeneous enhancement in the great majority (70%).

Endoscopic ultrasound-guided percutaneous endoscopic gastrostomy

Percutaneous endoscopic gastrostomy (PEG) is the method of choice for feeding and nutritional support in patients with a normal gastrointestinal function who require long-term enteral nutrition. We report our experience regarding an alternative endoscopic ultrasound (EUS)-guided PEG technique. A retrospective clinical experience case series study was conducted from January 2019 to November 2019 at a tertiary center. Adult patients deemed unfit for conventional PEG due to absence of transillumination or previous gastric surgery were enrolled. An EUS target was created by filling a glove with saline and placing it in the abdomen. EUS was performed and the target identified from the stomach. The abdominal wall was punctured from the stomach and a guidewire was advanced. The guidewire was knotted to a string, which was passed into the stomach and drawn back through the mouth. The procedure was continued following the traditional technique. Four patients underwent EUS-PEG in our center during the study period. Mean age was 65 years and 50% were male. Two patients (50%) had a body mass index over 30. PEG indications were tongue malignancies (50%), cerebrovascular disease (25%) and dementia (25%). One patient had a Roux-en-Y gastric bypass and percutaneous endoscopic jejunostomy was performed. Technical success rate was 100% and no complications occurred. This case series shows that the EUS-guided PEG technique is a safe alternative in patients deemed unfit for conventional PEG.

A State-of-the-Art Review on the Evolving Utility of Endoscopic Ultrasound in Liver Diseases Diagnosis

Liver diseases are amongst the most common diseases worldwide and manifest as a parenchymatic and/or biliary injury due to several causes as well as focal liver lesions, ranging from benign to malignant ones. The diagnosis of liver diseases is based mainly on biochemical and advanced imaging studies and, when required, on liver biopsy. Endoscopic ultrasound (EUS), which combines endoscopy and ultrasonography, is one of the main examination techniques used in gastroenterology as it is applied to evaluate abnormalities in the lumen of the upper and lower gastrointestinal tract and to define pancreatic and hepato-biliary features, often in chronic patients. Given its high spatial resolution and its proximity to the liver, EUS is gaining popularity in the diagnostic work up of liver diseases. This is a comprehensive overview of the current literature on the diagnostic indications for EUS use in patients with liver diseases. We performed a MEDLINE\PubMed and Embase search, and all articles that were relevant, after reviewing abstracts, were assessed and the full text was analyzed to extract data regarding technical success, diagnostic yield, bioptic characteristics, and complications rate. EUS-guided imaging and biopsy techniques in liver diseases have shown consistent favorable promising results among the reports through the literature, with an excellent diagnostic yield and safety profile, especially in the context of focal lesions and portal hypertension. The application of EUS in the diagnosis of liver diseases is a promising technique and should be considered as a first-line therapeutic option in selected cases.

A new minimally invasive porcine model for the study of intrahepatic bile duct dilatation

BACKGROUND

Endoscopic ultrasound (EUS) procedures are becoming more frequent nowadays and novel techniques are on the rise. These procedures require high technical experience and complex endoscopic skills. The goal of this study was to develop a new minimally invasive animal model of bile duct dilatation in the pig, in order to offer a new tool for endoscopic and surgical therapy training and to test new therapeutic strategies.

METHODS

Twenty-five female pigs underwent laparoscopic surgery in order to perform a common hepatic duct ligation. A pre- and postoperative biochemical analyses were performed: glucose, albumin, total bilirubin (TBil), gamma glutamyl transferase (GGT), alkaline phosphatase, and alanine aminotransferase were measured. Surgical time and intra- and postoperative complications were registered. Five to six days after surgery, an EUS was performed to measure intrahepatic duct size (mm). Distance from the bile duct to the EUS transductor was also recorded (mm). T-student for quantitative variables was applied. Statistical significance was defined as p value ≤ 0.05.

RESULTS

The mean surgical time was 29.5 ± 14.9 min. In five pigs (20%), some mild intraoperative problems occurred. A severe postoperative complication occurred in one animal (4%). No postoperative mortality was registered. Postoperative serum analyses showed an increase in total bilirubin (p = 0.005) and gamma glutamyl transferase levels (p = 0.001). Postoperative EUS showed dilatation of the intrahepatic bile duct in 76% of pigs, with a mean diameter of 9.6 ± 3.6 mm (distance from the gastric wall of 17.0 ± 6.4 mm).

CONCLUSION

The surgical procedure described here is a safe technique to induce dilatation of the intrahepatic bile ducts in the pig, with a minimally invasive approach and a high efficacy rate. This animal model might be useful for EUS techniques training and for evaluating new therapeutic approaches.

Endoscopic ultrasound guided liver biopsy: Recent evidence

Liver biopsy (LB) is an essential tool in diagnosing, evaluating and managing various diseases of the liver. As such, histopathological results are critical as they establish or aid in diagnosis, provide information on prognosis, and guide the appropriate selection of medical therapy for patients. Indications for LB include evaluation of persistent elevation of liver chemistries of unclear etiology, diagnosis of chronic liver diseases such as Wilson's disease, autoimmune hepatitis, small duct primary sclerosing cholangitis, work up of fever of unknown origin, amyloidosis and more. Traditionally, methods of acquiring liver tissue have included percutaneous LB (PCLB), transjugular LB (TJLB) or biopsy taken surgically via laparotomy or laparoscopy. However, traditional methods of LB may be inferior to newer methods. Additionally, PCLB and TJLB carry higher risks of adverse events and complications. More recently, endoscopic ultrasound guided LB (EUS-LB) has evolved as an alternative method of tissue sampling that has proven to be safe and effective, with limited adverse events. Compared to PC and TJ routes, EUS-LB may also have a greater diagnostic yield of tissue, be superior for a targeted approach of focal lesions, provide higher quality images and allow for greater patient comfort. These advantages have contributed to the increased use of EUS-LB as a technique for obtaining liver tissue. Herein, we provide a review of the recent evidence of EUS-LB for liver disease.

Endoscopic ultrasound guided liver biopsy for parenchymal liver disease

Liver biopsy plays an essential role in the diagnosis, evaluation and management of a vast proportion of liver diseases. Conventionally, percutaneous and trans-jugular approaches have been used to obtain liver biopsies. Endoscopic ultrasound guided liver biopsy (EUS-LB) has emerged as a safe and effective alternate in the past two decades. EUS-LB carries a role in evaluation of both benign and malignant diseases of the liver. It can offer higher resolution imaging of the liver and can detect smaller lesions than computed tomography scan of the abdomen or ultrasound scans with the option for doppler assistance to reduce complications. Current evidence demonstrates the superiority of EUS-LB for a targeted approach of focal lesion and there is also evidence of less sampling variability in heterogeneous parenchymal pathologies. These advantages combined with an improved safety profile had led to the rapid progress in the development of new techniques, equipment and procedures for EUS-LB. We provide a comprehensive review of EUS-LB for parenchymal liver disease.

Endoscopic ultrasound in pediatric population: a comprehensive review of the literature

Background and aim: Endoscopic ultrasonography (EUS) with or without fine needle aspiration/biopsy (FNA/B) is a well-established diagnostic tool in adults for the evaluation and management of gastrointestinal (GI) tract disorders. Its use in children is still limited as well as literature in pediatric age is limited, although the application of EUS is now increasing. The present article aims to review the current literature about EUS indication, accuracy and safety in pediatric age. Methods: Electronic literature searches were conducted using Pubmed, Medline, Embase, and the Cochrane Central Register of Controlled Trials using the word pediatric endoscopic ultrasound, pediatric pancreaticobiliary AND/OR EUS, pediatric EUS technique. Main patients and procedures characteristics were analyzed. The primary endpoint was the indication of EUS. Secondary endpoints were the accuracy of the technique and the incidence of complications. Results: Data were extracted from 19 articles. A total of 571 patients were investigated, with a median age of 12,7 years. A total of 634 EUS procedures were performed. The majority of EUS procedures investigated the pancreaticobiliary tract (77,7%). Most studies showed a high positive impact on management with a median value of 81,7%. No major complications were reported. Five studies reported minor complications with a median value of 2%. Conclusions: EUS is safe and has a significant role in the diagnosis of pancreaticobiliary and GI diseases even in children, with a high therapeutic success. An increasing EUS utilization by pediatric gastroenterologists is expected and offering dedicated EUS training to some selected pediatric gastroenterologists might be indicated. (www.actabiomedica.it)

A quarter century of EUS-FNA: Progress, milestones, and future directions

Tissue acquisition using EUS has considerably evolved since the first EUS-FNA was reported 25 years ago. Its introduction was an important breakthrough in the endoscopic field. EUS-FNA has now become a part of the diagnostic and staging algorithm for the evaluation of benign and malignant diseases of the gastrointestinal tract and of the organs in its proximity, including lung diseases. This review aims to present the history of EUS-FNA development and to provide a perspective on the recent developments in procedural techniques and needle technologies that have significantly extended the role of EUS and its clinical applications. There is a bright future ahead for EUS-FNA in the years to come as extensive research is conducted in this field and various technologies are continuously implemented into clinical practice.