EUS access to the biliary tree

Interventional Endoscopic Ultrasound: Current Status and Future Directions

The evolution of endoscopic ultrasound (EUS) from a diagnostic to a therapeutic procedure has resulted in a paradigm shift toward endoscopic management of disease states that previously required percutaneous or surgical approaches. The past few years have seen additional techniques and devices that have enabled endoscopists to expand its diagnostic and therapeutic capabilities. Some of these techniques initially were reported more than a decade ago; however, with further device development and refinement in techniques there is potential for expanding the application of these techniques and new technologies to a broader group of interventional gastroenterologists. Lack of formalized training, devices, and prospective data regarding their use in addition to a scarcity of guidelines on implementation of these technologies into clinical practice are contributing factors impeding the growth of the field of interventional EUS. In April 2019, the American Gastroenterological Association's Center for Gastrointestinal Innovation and Technology conducted its annual Tech Summit and a key session focused on interventional EUS. This article is a White Paper generated from the conference, discusses the published literature pertaining to the topic of interventional EUS, and outlines a proposed framework for the implementation of interventional EUS techniques into clinical practice. Three primary areas of interventional EUS are addressed: (1) EUS-guided access; (2) EUS-guided tumor ablation; and (3) endohepatology. There was general agreement among participants on several key components. The introduction of these novel interventions requires better tools, more data on safety/outcomes, and improved training for endoscopists. Participants also agreed that widespread implementation and use of these techniques will require support from Gastrointestinal Societies and other key stakeholders including payers. Continued work by the Gastrointestinal Societies and manufacturers to provide training programs, appropriate equipment/work environments, and policies that motivate endoscopists to adopt new techniques is essential for growing the field of interventional EUS.

A prospective, controlled assessment of the technical characteristics of a novel forward-viewing echoendoscope

INTRODUCTION

endoscopic ultrasound (EUS) is a highly useful technique for the diagnosis and management of different gastrointestinal (GI) tract conditions.

OBJECTIVE

to prospectively assess the clinical usefulness of a novel forward-viewing echoendoscope (FV-CLA).

METHODS

this was a cross-sectional observational study. All patients that underwent EUS over a two-month period were considered for the study. All mediastinal, perigastric and periduodenal stations were consistently assessed with a rating from 0 to 10 points with regard to the ease to obtain ultrasonographic sections and the quality of ultrasound images. The identified lesions were punctured when clinically indicated.

RESULTS

a total of 45 patients were included. EUS was completed in 100% of patients, with two minor complications recorded. Echoendoscope maneuverability was graded as "A" (9-10 points), overall plane visibility was graded as "B" (7-8 points) and only stations 4L and 5 visualization were graded as "D" (< 7 points). Visualization of the pancreas and the rest of the EUS stations were rated as excellent or very good. The feasibility to perform EUS-FNA, even from the second portion of the duodenum, was graded excellent or very good.

CONCLUSION

the FV-CLA allows a complete, high-quality examination of the upper GI tract, including EUS-FNA punctures. Some mediastinal stations are hardly accessible with this new device. A formal validation of the FV-CLA for EUS-guided therapy would be of interest.

EUS-guided biliary drainage or enteroscopy-assisted ERCP in patients with surgical anatomy and biliary obstruction: an international comparative study

Background and study aims: How enteroscopy-assisted ERCP (e-ERCP) and endoscopic ultrasound-guided biliary drainage (EUS-BD) compare in patients with surgically altered upper gastrointestinal anatomy is currently unknown. The aims of this study were to compare efficacy and safety of both techniques and study predictors of these outcomes. Patients and methods: This was an international, multicenter comparative cohort study at 10 tertiary centers. Outcomes data included technical success (biliary access with cholangiography and stent placement [when indicated]), clinical success (resolution of biliary obstruction) and adverse events (AEs) (graded according to the ASGE lexicon). Results: A total of 98 patients underwent EUS-BD (n = 49) or e-ERCP (n = 49). Technical success was achieved in 48 (98 %) patients in the EUS-BD group as compared to 32 (65.3 %) patients in the e-ERCP group (OR 12.48, P = 0.001). Clinical success was attained in 88 % of patients in EUS-BD group as compared to 59.1 % in the e-ERCP group (OR 2.83, P = 0.03). Procedural time was significantly shorter in the EUS-BD group (55 min vs 95 min, P < 0.0001). AEs occurred more commonly in the EUS-BD group (20 % vs. 4 %, P = 0.01). However, the majority (90 %) of AEs were mild/moderate. Length of stay was significantly longer in the EUS-BD group (6.6 d vs. 2.4 d, P < 0.0001). Conclusions: EUS-BD can be performed with a higher degree of clinical efficacy and shorter procedure time than e-ERCP in patients with surgically-altered upper gastrointestinal anatomy. Whether or not this approach should be first-line therapy in this patient population is highly dependent on the indication for the procedure, the patient's anatomy, and local practice and expertise.

Endoscopic Ultrasound-Guided Treatment beyond Drainage: Hemostasis, Anastomosis, and Others

Since the introduction of endoscopic ultrasound (EUS) in the 1990s, it has evolved from a primarily diagnostic modality into an instrument that can be used in various therapeutic interventions. EUS-guided fine-needle injection was initially described for celiac plexus neurolysis. By using the fundamentals of this method, drainage techniques emerged for the biliary and pancreatic ducts, fluid collections, and abscesses. More recently, EUS has been used for ablative techniques and injection therapies for patients with for gastrointestinal malignancies. As the search for minimally invasive techniques continued, EUS-guided hemostasis methods have also been described. The technical advances in EUS-guided therapies may appear to be limitless; however, in many instances, these procedures have been described only in small case series. More data are required to determine the efficacy and safety of these techniques, and new accessories will be needed to facilitate their implementation into practice.