Tips to overcome technical challenges in EUS-guided tissue acquisition

Image Fusion Involving Real-Time Transabdominal or Endoscopic Ultrasound for Gastrointestinal Malignancies: Review of Current and Future Applications

Image fusion of CT, MRI, and PET with endoscopic ultrasound and transabdominal ultrasound can be promising for GI malignancies as it has the potential to allow for a more precise lesion characterization with higher accuracy in tumor detection, staging, and interventional/image guidance. We conducted a literature review to identify the current possibilities of real-time image fusion involving US with a focus on clinical applications in the management of GI malignancies. Liver applications have been the most extensively investigated, either in experimental or commercially available systems. Real-time US fusion imaging of the liver is gaining more acceptance as it enables further diagnosis and interventional therapy of focal liver lesions that are difficult to visualize using conventional B-mode ultrasound. Clinical studies on EUS guided image fusion, to date, are limited. EUS-CT image fusion allowed for easier navigation and profiling of the target tumor and/or surrounding anatomical structure. Image fusion techniques encompassing multiple imaging modalities appear to be feasible and have been observed to increase visualization accuracy during interventional and diagnostic applications.

Comparison of Endoscopic Ultrasound-Guided Tissue Acquisition Using a 20-Gauge Menghini Needle with a Lateral Forward Bevel and a 22-Gauge Franseen Needle: A Single-Center Large Cohort Study

Background/Aims

Several fine-needle biopsy (FNB) needles are available for endoscopic ultrasound (EUS)-guided tissue acquisition. However, there is disagreement on which type of needle has the best diagnostic yield. The aim of this study was to compare the performance and safety of two commonly used EUS-FNB needles.

Methods

We retrospectively analyzed consecutive patients who underwent EUS-FNB between June 2016 and March 2020 in our hospital. Two types of needles were evaluated: a 20-gauge Menghini needle with a lateral forward bevel and a 22-gauge Franseen needle. Rapid on-site evaluation was performed in all the cases. A multivariate analysis was performed to clarify the negative predictive factors for obtaining a histological diagnosis. Propensity score matching was performed to compare the diagnostic yields of these two needles.

Results

We analyzed 666 patients and 690 lesions. The overall diagnostic rate of histology alone was 88.8%, and the overall adverse event rate was 1.5%. Transduodenal access and small lesions (≤2 cm) were identified as negative predictive factors for obtaining a histological diagnosis. After propensity score matching, 482 lesions were analyzed. The diagnostic accuracy rates of histology in the M and F needle groups were 89.2% and 88.8%, respectively (p=1.00).

Conclusions

Both the needles showed high diagnostic yield, and no significant difference in performance was observed between the two.

Current Status of Needles in the Optimization of Endoscopic Ultrasound-Guided Procedures

Endoscopic ultrasound (EUS) is among the most important tools for the evaluation of gastrointestinal tumors and affected areas around the gastrointestinal tract. It enables the acquisition of material from abnormal lesions via the gastrointestinal wall for tissue confirmation via endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA). EUS-FNA has played a vital role in oncological care and has become the standard method for tissue sampling. The choice of needle type is an important factor determining tissue acquisition and has been evaluated by many researchers. New needles are introduced into the market almost every year, and opinions vary regarding proper needle selection. While there are diverse opinions but no definitive recommendations about the use of one particular device, fine-needle biopsy needles may provide detailed information on a tissue’s architecture based on greater sample yields. This permits additional analyses, including genetic sequencing and phenotyping, thereby enabling the provision of more personalized treatment plans. Furthermore, other EUS-guided procedures have been developed, including interventional EUS and through-the-needle devices. Given the continued attempts to improve the diagnostic ability and therapeutic techniques, we review in detail the available types of puncture needles to provide guidance on the selection of the appropriate needle types.

Endoscopic ultrasonography and small-bowel endoscopy: Present and future

Over the last decade, impressive technological advances have occurred in ultrasonography and small-bowel endoscopy. Nowadays, endoscopic ultrasonography is an essential diagnostic tool and a therapeutic weapon for pancreatobiliary disorders. Capsule endoscopy and device-assisted enteroscopy have quickly become the reference standard for the diagnosis of small-bowel luminal diseases, thereby leading to radical changes in diagnostic and therapeutic pathways. We herein provide an up-to-date overview of the latest advances in endoscopic ultrasonography and small-bowel endoscopy, focusing on the emerging paradigms and technological innovations that might improve clinical practice in the near future.

Endoscopic ultrasound-guided sampling of solid pancreatic masses: the fine needle aspiration or fine needle biopsy dilemma. Is the best needle yet to come?

Fine needle aspiration (FNA) is currently the standard of care for sampling pancreatic solid masses by using endoscopic ultrasound (EUS). The accuracy of the technique is reported to be high, especially if coupled with the rapid on site evaluation (ROSE), and it has a high safety profile. However, FNA presents some limitations, such as the small amount of tissue that can be collected and the inability of obtaining a core tissue with intact histological architecture, which is relevant to perform immunohistochemical analysis, molecular profiling and, therefore, targeted therapies. Moreover, the presence of the ROSE by an expert cytopathologist is very important to maximize the diagnostic yield of FNA technique; however, it is not widely available, especially in small centers. Hence, the introduction of EUS fine needle biopsy (FNB) with a new generation of needles, which show a high safety profile too and a satisfying diagnostic accuracy even in the absence of ROSE, could be the key to overcome the limitations of FNA. However, FNB has not yet shown diagnostic superiority over FNA. Considering all the technical aspects of FNA and FNB, the different types of needle currently available, comparisons in term of diagnostic yield, and the different techniques of sampling, a tailored approach should be used in order to determine the needle that is most appropriate for the different specific scenarios.

Endoscopic ultrasonography in pancreatic diseases: advances in tissue acquisition

Background and study aims  Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) improved the diagnostic performance and upgraded the role of endoscopic ultrasonography (EUS) into an interventional modality, able to guide patient management and treatment.This review aimed to highlight the advances, emerging practices, procedural techniques and technological innovations in EUS tissue acquisition in pancreatic diseases. Methods  A thorough review of the literature was performed using PubMed to identify articles that describe techniques, advances, and practices in EUS tissue acquisition in gastrointestinal diseases. Conclusion  Since the first EUS-FNA procedure, EUS guided-tissue acquisition has been evolving continuously. Development of needles with innovative tip design enabled procurement of larger samples with preserved histological architecture. Moreover, sampling techniques and complementary methods, such as contrast harmonic imaging and EUS-elastography, have been introduced in an effort to improve diagnostic performance and sample adequacy.

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.

Endosonographer-driven dynamic telecytopathology of pancreatic lesions-a pilot study

INTRODUCTION

Telecytopathology for endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) has been shown to be an alternative to rapid on-site evaluation (ROSE). Gastroenterologists (endosonographers) performing EUS-FNA can be trained to evaluate a specimen for adequacy. This study examined the ability of an endosonographer with focused cytopathologic training to assess the adequacy of pancreatic FNA specimens and transmit diagnostic images to a remotely located cytopathologist as compared to an experienced cytotechnologist.

MATERIALS AND METHODS

This was a retrospective study of consecutive pancreatic lesions sampled by EUS-FNA reviewed by an endosonographer and a cytotechnologist. The participants were assessed based on their ability to (1) determine adequacy, (2) locate and transmit representative cell groups, (3) provide a preliminary diagnosis, and (4) provide concordance with actual diagnosis.

RESULTS

105 consecutive cases of EUS-FNA of the pancreas were analyzed, including: adenocarcinoma (n = 39), cyst (n = 17), neuroendocrine neoplasia (n = 7), pancreatitis (n = 14), benign pancreas (n = 9), other neoplasms (n = 6), suspicious/atypical (n = 3), and nondiagnostic (n = 10). The cytotechnologist demonstrated superiority in accuracy 92.7% versus 70% (P = 0.003) and subcategorization 95.0% versus 76% (P = 0.007). There was no difference in "broad" categorization (benign/malignant) between the endosonographer and cytotechnologist, 98% and 98.2% (P = 0.946), respectively. Also, there was no difference with regard to adequacy assessment (P = 0.29). A steady learning curve for the endosonographer was demonstrated in their cytologic assessment (P = 0.041). The endosonographer was shown to be able to remotely transmit diagnostic images to a pathologist.

CONCLUSION

An endosonographer with limited training can examine for specimen adequacy, transmit images, and demonstrate representative cell groups. Larger studies are required though preliminary results are encouraging.

Endoscopic Ultrasound-Guided Fine-Needle Aspiration of Pancreatic Lesions: A Systematic Review of Technical and Procedural Variables

Endoscopic ultrasound (EUS)-guided tissue acquisition has emerged over the last decade as an invaluable diagnostic tool in approaching the different pancreatic lesions. Given the safety and minimal invasiveness of this approach combined with the high diagnostic yield, it became the standard of care when dealing with different pancreatic pathologies. However, some variables regarding this procedure remain not fully understood. These can influence the diagnostic yield of the procedure and include the presence of the on-site cytopathologist, the type and size of the needle used as well as obtaining aspiration versus core biopsy, the number of passes and the sampling technique, and the role of suction and stylet use among others. We performed a comprehensive literature search using PubMed, Google Scholar, and Embase for studies that assessed these variables. Eligible studies were analyzed using several parameters such as technique and procedure, with the aim of reviewing results from an evidence-based standpoint.

A novel fusion imaging system for endoscopic ultrasound

Background and Objective:

Navigation of a flexible endoscopic ultrasound (EUS) probe inside the gastrointestinal (GI) tract is problematic due to the small window size and complex anatomy. The goal of the present study was to test the feasibility of a novel fusion imaging (FI) system which uses electromagnetic (EM) sensors to co-register the live EUS images with the pre-procedure computed tomography (CT) data with a novel navigation algorithm and catheter.

Methods:

An experienced gastroenterologist and a novice EUS operator tested the FI system on a GI tract bench top model. Also, the experienced gastroenterologist performed a case series of 20 patients during routine EUS examinations.

Results:

On the bench top model, the experienced and novice doctors reached the targets in 67 ± 18 s and 150 ± 24 s with a registration error of 6 ± 3 mm and 11 ± 4 mm, respectively. In the case series, the total procedure time was 24.6 ± 6.6 min, while the time to reach the clinical target was 8.7 ± 4.2 min.

Conclusions:

The FI system is feasible for clinical use, and can reduce the learning curve for EUS procedures and improve navigation and targeting in difficult anatomic locations.