Endoscopic ultrasonography in chronic pancreatitis.

The diagnosis of chronic pancreatitis is based on clinical grounds, testing of pancreatic function, and imaging modalities, of which endoscopic retrograde cholangiopancreatography (ERCP) is considered presently as the "gold standard." Endoscopic ultrasound (EUS) can visualize pancreatic ductal and parenchymal alterations, allowing for distinguishment of the normal pancreas from different grades of severity of chronic pancreatitis. As a supplement to findings obtained by ERCP, EUS delineates a subgroup of patients exhibiting definite parenchymal changes despite normal duct findings on ERCP. EUS should be regarded as a superior diagnostic tool in the imaging of the chronically inflamed pancreas and should be performed early in a patient with abdominal pain of suspected pancreatic etiology.