Procedures and interventions
We prospectively included consecutive patients with pancreatic masses needing EUS‐FNA followed CH‐EUS examination. After traditional EUS, CH‐EUS was performed, two experienced endoscopists watched the screen and determined the nature of the lesion immediately after CH‐EUS, based on the black and white images. Then CH‐EUS MASTER gave the TIC of ROI 1 N and ROI 2, also generated the cancerous or noncancerous judgment of the mass. This study was approved by The Institutional Review Board of The Third Xiangya Hospital of Central South University (protocol number: 2019‐S560).Patients were then randomly assigned to undergo EUS‐FNA with or without the guidance of CH‐EUS MASTER for the first two passes. In order to ensure patient rights to the best standard‐of‐care and comparability, for the control group, the first two passes were made without CH‐EUS MASTER guidance during FNA, and then two passes were made under guidance from CH‐EUS MASTER; for the CH‐EUS MASTER group, the first two passes were made with CH‐EUS MASTER guidance and then another two manual passes without CH‐EUS MASTER guidance. Only the results of the first two passes were included in the statistical analysis.These examinations were performed under intravenous anesthesia. All the EUS and follow‐up examinations were performed by experienced endoscopists using ME2 and endoscopes (Olympus Medical Systems Co). The 22‐gauge FNA needles (Cook Medical, Winston Salem, NC; Expect; Boston Scientific, Marlborough, MA, USA) catheter system was used to obtain samples.