[Clinical evaluation of endoscopic ultrasonography in diagnosis of chronic pancreatitis].

Usefulness of endoscopic ultrasonography (EUS) for the diagnosis of chronic pancreatitis, particularly for mild chronic pancreatitis and so-called clinically suspected chronic pancreatitis diagnosed by the criteria documented by the Committee of Japanese Society of Gastroenterology for chronic pancreatitis (CJSG criteria), is described in this paper. 89 patients with chronic pancreatitis including 43 with mild chronic pancreatitis (MIP), 29 with moderate chronic pancreatitis (MOP) and 17 with advanced chronic pancreatitis (ADP) diagnosed by Endoscopic Retrograde Cholangio-Pancreatography (ERCP) were selected for the study and following results were obtained. 1) The number of findings of wall irregularity of the main pancreatic duct and heterogeneity of the pancreatic parenchyma were more clearly shown by EUS although they had been classified as suspicious of chronic pancreatitis diagnosed by conventional US by the CJSG criteria. 2) The pancreatic parenchymal echo pattern by EUS can be divided into 6 patterns, rough-high echo, spotty-high echo, linear-high echo, rough-low echo, diffuse-high echo and diffuse-low echo. 3) Spotty high echo was observed in high rate in the patients even with MIP showing only a slight change of the main pancreatic ducts by ERCP. Therefore, this pattern could be present in early stage of chronic pancreatitis. 4) The pancreatic parenchymal change by aging detected by EUS was often seen as linear-high and/or diffuse-high echo patterns. 5) Differentiation of changes of the pancreatic parenchyma and wall of the main pancreatic duct by chronic pancreatitis from the change by aging was possible by using EUS. 6) By macro- and micro-scopic studies of the pancreatic parenchyma, pancreatic calculus, fatty change and irregular fibrosis were shown by EUS as rough-high echo accompanied by acoustic shadow, spotty-high echo and rough-low echo patterns respectively.