Clinical significance of manometric assessment of both pancreatic duct and bile duct sphincter in the same patient

In this study both pancreatic and bile duct sphincter pressures were measured on the same occasion by means of endoscopic manometry in 42 patients with long-standing upper abdominal pain. Nine (53%) of the 17 patients with abnormal sphincter function had a marked difference between the pancreatic duct sphincter pressure (PSOP) and the bile duct sphincter pressure (BSOP): 6 patients with a clinical diagnosis of biliary dyskinesia showed elevated BSOPs, whereas the PSOPs were normal. The reverse, an abnormal PSOP but normal or only a slightly elevated BSOP, was registered in the three patients with chronic pancreatitis. These findings indicate that a motor abnormality may be restricted to only one of the sphincters. Thus, when the sphincter of Oddi is investigated only from the pancreatic duct, manometry may either fail to show an abnormal BSOP in some patients with biliary dyskinesia, or it may falsely suggest this diagnosis in patients with unrecognized pancreatitis.