Relation between morphologic changes in the main pancreatic duct and exocrine pancreatic function after a secretin test.

Abstract

Because pancreatic exocrine function testing methods are problematic, both imaging and functional tests are important in the diagnosis of chronic pancreatitis. To evaluate the usefulness of ultrasonographic monitoring of the main pancreatic duct after a secretin test. A total of 70 subjects (30 control subjects, 26 patients with probable chronic pancreatitis, and 14 patients with definite chronic pancreatitis) were selected. The main pancreatic duct diameters were measured serially after an injection of secretin (100 IU/body). The relation between the magnitude of the duct dilation and exocrine pancreatic function on the secretin test was evaluated. The main pancreatic duct dilated immediately after a bolus injection of secretin, showed a peak after 2-5 minutes, and recovered gradually. The response curve of the definite group had a flatter pattern than that of the other groups. For the maximal to basal duct diameter ratio, statistically significant differences were found between the control and definite groups and between the control and probable groups. In addition, the ratio correlated significantly with the maximal bicarbonate concentration and secretory volume on the secretin test. The results of the current study indicate that exocrine pancreatic function and the morphologic changes of the main pancreatic duct are significantly related. Dynamic ultrasonographic findings may reflect pancreatic function; consequently, this test may be a useful tool in the diagnosis of chronic pancreatitis.