Diagnosis of chronic pancreatitis by means of a sonographic secretin test.

The pancreatic duct can be demonstrated today by sonography in about 90% of all persons examined. In 159 persons, aged 18-79 yr, we measured sonographically the pancreatic duct diameter before and after intravenous secretin injection. After secretin stimulation, 20 healthy controls and 90 patients without pancreatic disease showed a distinct pancreatic duct dilatation of 93 and 94% of basal duct diameter lasting only several minutes. No distinct secretin-induced duct enlargement was observed in 35 of 40 patients with chronic pancreatitis. Patients with chronic pancreatitis and circumscript duct stenosis even had a marked and longer-lasting duct dilatation of 156% of basal duct diameter after secretin stimulation. This study showed a high reliability of the sonographic secretin test in the diagnosis of chronic pancreatitis--even in an early stage--recording a sensitivity of 92.5%, a specificity of 93%, and a predictive value of 84%.