An electronic radial scanning echoendoscope is superior to a mechanical radial scanning echoendoscope in ultrasound image quality for gastrointestinal tract and pancreaticobiliary lesions

Evaluation of a novel radial echoendosonoscope with a piezoelectric-composite transducer: An open-label, multicenter, randomized, parallel-group, noninferiority clinical trial

BACKGROUND AND OBJECTIVES

EUS is widely used in the clinical practice. This study aimed to evaluate the efficacy of a novel echoendoscope regarding image quality, maneuverability, stability of the entire machine system, and safety.

SETTING AND DESIGN

We conducted this open-label, multicenter, randomized, parallel-group, noninferiority clinical trial in three tertiary hospitals between November 2018 and April 2019.

SUBJECTS AND METHODS

One hundred and thirty patients were included. The stratified segment randomization method was employed. Sixty-five patients in the test group received an EUS examination using the new material radial echoendoscope, and 65 patients in the control group received an EUS examination using the existing endoscope. We recorded the image quality, maneuverability, stability of the entire machine system, and safety. For the main outcome, comprehensive image quality, the groups were compared with the noninferiority test, using the confidence interval method and 10% as the noninferiority threshold. The Pearson Chi-square test was used to compare the incidence of adverse events between the groups.

RESULTS

Sixty-five patients in the test group and 63 patients in the control group were analyzed. Two patients in control group did not complete an EUS examination due to machine problems. There were no significant differences in image quality, maneuverability of the echoendoscope, stability of the entire machine system, and safety between the groups.

CONCLUSIONS

This new material radial echoendoscope showed good capabilities for image quality, maneuverability, stability of the entire machine system, and safety. Our data suggest that the new echoendoscope may provide an additional option for endoscopic physicians.

What should be known prior to performing EUS exams? (Part II)

In “What should be known prior to performing EUS exams, Part I,” the authors discussed the need for clinical information and whether other imaging modalities are required before embarking EUS examinations. Herewith, we present part II which addresses some (technical) controversies how EUS is performed and discuss from different points of view providing the relevant evidence as available. (1) Does equipment design influence the complication rate? (2) Should we have a standardized screen orientation? (3) Radial EUS versus longitudinal (linear) EUS. (4) Should we search for incidental findings using EUS?

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.

Assessing the imaging capabilities of radial mechanical and electronic echo-endoscopes using the resolution integral

Over the past decade there have been significant advances in endoscopic ultrasound (EUS) technology. Although there is an expectation that new technology will deliver improved image quality, there are few methods or phantoms available for assessing the capabilities of mechanical and electronic EUS systems. The aim of this study was to investigate the possibility of assessing the imaging capability of available EUS technologies using measurements of the resolution integral made with an Edinburgh Pipe Phantom. Various radial EUS echo-endoscopes and probes were assessed using an Edinburgh Pipe Phantom. Measurements of the resolution integral (R), depth of field (LR) and characteristic resolution (DR) were made at all operating frequencies. The mean R value for Fuji miniprobes was 16.0. The GF-UM20 and GF-UM2000 mechanical radial scopes had mean R values of 24.0 and 28.5, respectively. The two electronic radial echo-endoscopes had similar mean R values of 34.3 and 34.6 for the Olympus GF-UE260 and Fujinon EG-530 UR scopes, respectively. Despite being older technology, the mechanical GF-UM2000 scope had superior characteristic resolution (DR), but could not compare with the depths of field (LR) delivered by the current generation of electronic radial scopes, especially at the standard operating frequencies of 7.5 and 12 MHz.

For biliary dilatation, a negative endosonography needs additional image studies in weight loss suggesting malignancy

BACKGROUND AND AIM

Biliary dilatation frequently raises concerns about the possibility of pancreatobiliary diseases. This study assessed the etiologic yield of endosonography (EUS) in this situation.

METHODS

A retrospective review was completed with 163 consecutive patients who had undergone EUS for a dilated common bile duct (CBD) without definite pathology on ultrasonography.

RESULTS

Binary logistic regression analysis disclosed that malignancy was positively related to weight loss and was inversely related to abdominal pain; nevertheless, choledocholithiasis was positively related to fever and elevated carbohydrate antigen 19-9 (p < 0.05). The accuracy of EUS was 95.1 % (155/163) for overall cause of biliary dilatation, 100 % (73/73) for no pathological finding, 96.3 % (26/27) for ampullary cancer, 84.6 % (11/13) for pancreatic cancer, 40.0 % (2/5) for CBD cancer, and 92.6 % (25/27) for choledocholithiasis, respectively. The accuracy of EUS decreased in the presence of malignancy (86.7 %, 39/45 vs. 98.3 %, 116/118, p = 0.006). EUS missed three CBD cancers, two pancreatic cancers, and one ampullary cancer; however, the diagnosis was rescued by computed tomography in two pancreatic cancers and one CBD cancer.

CONCLUSIONS

EUS is accurate in patients with fever suggestive of choledocholithiasis. However, a negative EUS finding should call for additional image studies in patients with weight loss suggestive of malignancy.