MRI of pancreatic duct changes in piglets with chronic pancreatitis

Abstract

Objective To study MRI findings of pancreatic ducts of piglets with chronic pancreatitis (CP) induced by pancreatic duct ligation and analyze the relationship between pancreatic duct changes in piglets with CP and the pathological severity of CP. Methods Thirty healthy piglets were included in this study. Five piglets were randomly selected as normal control group, and the remaining 25 piglets were served as the experimental group. The duct ligation operations were performed on experimental group. After 2 to 18 weeks, pancreas and pancreatic ducts were observed on MRI. Then the pancreas was removed and graded into three types by histopathology. The relationship between the diameter of pancreatic duct or the pancreatic branch displaying rate and the severity of CP was analyzed by Spearman correlation coefficient. Results CP was found in 21 piglets( 84. 0% ) in the experimental group including mild ( n = 7 ), moderate ( n = 8 ) and severe( n = 6) pancreatitis. Pancreatic ducts were shown in mild CP and the edge of pancreatic ducts was irregular in three cases. The dilated RPD, LPD and MPD constituted the person form in moderate and severe CP. The diameter of pancreatic ducts was(0. 9 ±0. 3)mm, (2. 9 ± 1.4)mm and (4. 8 ± 1.2)mm in mild, moderate, and severe CP respectively. The expansion extent of pancreatic ducts was correlated with the severity of CP of piglets (r = 0. 837, P ＜ 0. 05). The pancreatic branch displaying rate increased with the increase of the severity of CP ( r = 0. 990, P ＜ 0. 05 ); the displaying rate was 0/7 for mild, 3/8 for moderate, and 5/6 for severe CP. Conclusions The dilated pancreatic ducts with person form in piglets with obstructive CP created by pancreatic duct ligation. The pancreatic duct changes on MRI reflect the severity of CP of piglets. Key words: Pancreatitis,chronic; Magnetic resonance imaging; Animals,laboratory