CONTRAST-ENHANCED ENDOSCOPIC ULTRASONOGRAPHY (CE-EUS) FOR PANCREATIC DISEASE

Abstract

Endoscopic ultrasonography (EUS) plays a particularly important role in the diagnosis of pancreatic disease. In recent years, with the development and improvements of the EUS scope and ultrasonic diagnostic equipment, EUS has been used for detection and making a qualitative diagnosis of pancreatic diseases. With the advent of color Doppler, power Doppler, ultrasound contrast agents, and ultrasound imaging method, the diagnostic approach for pancreatic disease, which is difficult to diagnose, has entered a new stage. In this paper, the role and usefulness of contrast-enhanced endoscopic ultrasonography (CE-EUS) for pancreatic disease, including the development and improvements of EUS equipment, are reviewed.

CE-EUS is indicated for the differential diagnosis of solid pancreatic tumors and cystic lesions of the pancreas, especially for diagnosis of the nodules or mucous masses in neoplastic cysts, and diagnosis of the stage of malignant pancreatic tumors (i.e., evaluation of mainly vascular invasion). In the EUS diagnosis of pancreatic disease, qualitative diagnosis becomes possible by adding blood flow information using an ultrasound contrast agent (CE-EUS), and the diagnostic accuracy has improved (not only sensitivity but also specificity has increased). Reports on the usefulness of CE-EUS have accumulated. Two meta-analyses of differential diagnosis of pancreatic solid masses, especially pancreatic cancer, by CE-EUS reported a sensitivity of 93-94% and a specificity of 88-89%, and its usefulness is described in the 2019 Pancreatic Cancer Practice Guidelines. CE-EUS diagnosis of cystic pancreatic lesions, especially neoplastic cysts, was reported to have a sensitivity of 100% and a specificity of 80-97% for identifying mural nodules. It is also reported that analysis of malignant nodule size, nodule / pancreatic parenchymal contrast ratio analysis, and analysis of mural nodule morphology and vascular distribution pattern are useful for the differential diagnosis between malignant or benign intraductal papillary mucosal neoplasms (IPMNs). From these reports, it is expected that a more accurate diagnosis of pancreatic diseases can be made faster than ever by CE-EUS.