Endoscopic treatment of the main pancreatic duct: correlations among morphology, manometry, and clinical follow-up.

Background and aim: During the course of chronic pancreatitis, the gradual increase in the main pancreatic duct pressure is the main pathophysiological factor responsible for pain, but up to now, the intra ductal pressure has never been measured during and after endoscopic stenting and correlated with clinical results. Pressure measurements of this kind could thus provide objective information about the useful duration of stenting period.

Methods: Main pancreatic duct pressure was measured by performing endoscopic manometry on 13 chronic pancreatitis symptomatic patients (10 men, 3 women, mean age: 45.1+/-7.9 yr); clinical follow-up was carried out for a period of 29.0+/-16.1 mo. Before treatment, the main anatomical alteration present was a localized stenosis of the main pancreatic duct, i.e., one with a diameter of less than 2 mm (chronic pancreatitis alone), 10 cases; chronic pancreatitis associated with pancreas divisum, 3 cases). Stenosis was treated by endoscopic stenting: 7 F stent (7 cases) and 12 F stent (6 cases). The pressure was measured simultaneously in the duodenum (zero level) and within the main pancreatic duct, using an electronic device, The pancreatico-duodenal gradient was taken to be the difference between the pressure in the main pancreatic duct and the duodenum.

Results: The endoscopic stenting induced a nonsignificant decrease in the intraductal pressure (p = 0.16). Among the 9 patients with a normal pressure at the end of the stenting and a successful anatomical outcome, 6 were painless during the follow-up period whereas 3 presented with recurrent pancreatic-type pain. The remaining 4 patients were symptom-free during the entire follow-up period, although the main pancreatic duct pressure was high at the end of the stenting and the stenosis was not completely cured.

Conclusion: The intraductal pressure at the end of the stenting period was perfectly correlated with the anatomical result, whether or not it was successful, but was not an accurate predictor of a favorable clinical outcome in patients with a poor anatomical result.