ALTERATIONS IN PANCREATIC DUCTAL MORPHOLOGY FOLLOWING POLYETHYLENE PANCREATIC STENT THERAPY

Background: Polyethylene stents placed in the main pancreatic duct ind uce morphologic alterations that may resemble chronic pancreatitis. Me thods: We reviewed the sequential pancreatograms of stented patients w ho had long-term follow-up after stent removal. Results: Forty patient s (66%) had a normal baseline pancreatogram, whereas 21 (34%) showed c hanges of chronic pancreatitis. In 49 of 61 patients (80.3%), one or m ore had new morphologic changes immediately after stent withdrawal gra ded as mild (69%), moderate (29%), or severe (2%). Changes included du ctal irregularity (49%), narrowing (35.5%), and side branch change(15. 5%). Sixteen of the 21 patients (76.1%) with an abnormal baseline panc reatogram had worsening of the baseline abnormality or additional chan ges while stented, whereas 33 of 40 (82.5%) with a normal baseline dev eloped new morphologic changes. Correlation of stent-induced changes w ith stent size, length, patency at removal, and duration of stenting f ailed to show an association. Twenty-five patients with stent-induced changes had a follow-up pancreatogram at a mean of 192 days (10 to 740 ) after stent removal. There was complete resolution of the changes in 64%, partial resolution in 32%, and no improvement in 5%. Conclusion: Morphologic changes induced by polyethylene pancreatic duct stents oc curred in 80% of patients. More than one third of these changes did no t resolve during the follow-up period. Because of concern over stent-i nduced fibrosis, the use of pancreatic stents should remain largely ex perimental.