Updates on EUS in Pancreatobiliary Disease

EUS evaluation of pancreatobiliary areas permits the obtainment of high resolution images and visualization of local anatomic details not detected by other imaging techniques. This coupled with ability to perform EUS-guided fine needle aspiration (EUS-FNA) to acquire tissue samples has rapidly made EUS one of the most important and accurate tools for the evaluation of both benign and malignant pancreatobiliary disorders. EUS-FNA, however, may be technically demanding and multiple puncturing of pancreatic lesions may be needed to obtain adequate material for cytologic evaluation. EUS-FNA for the pancreas furthermore is associated with a small, but not insignificant, morbidity. Pancreatic cancer can produce marked fibrotic reaction or necrosis and give false-negative results, which are obtained in up to 20%40% of the cases. Until recently, there was no contrast harmonic imaging technique available for EUS examination. Second-generation US contrast agents produce harmonic signals at lower acoustic powers and therefore, are suitable for EUS imaging at low acoustic powers. Elastography is a method for the real-time evaluation of tissue stiffness, which may be related histopathologic features. Recently these novel techniques have been clinically applied in the EUS evaluation of pancreatobiliary disorders. Here we will review and discuss the use of contrastenhanced EUS and EUS-elastography for the evaluation of pancreatobiliary disorders as well as new knowledge concerning the diagnostic EUS field.