Evaluation of MR multiparameter imaging for clinical classification of chronic pancreatitis
10.3760/cma.j.issn.1674-1935.2010.05.001
- VernacularTitle:MR多参数成像评估慢性胰腺炎临床分级的价值
- Author:
Mei BAI
;
Jianping LU
;
Xiaowei LAI
- Publication Type:Journal Article
- Keywords:
Pancreatitis,chronic;
Magnetic resonance imaging;
Dynamic enhanced MRI
- From:
Chinese Journal of Pancreatology
2010;10(5):305-308
- CountryChina
- Language:Chinese
-
Abstract:
Objective To investigate the value of MR multiparameter imaging for the clinical classification of chronic pancreatitis. Methods 65 patients with confirmed chronic pancreatitis by follow-up and pathologic examinations ( 14 mild, 37 moderate and 14 severe according to MANNHEIM system) and 20healthy volunteers were included in this study. MR examination including routine T1WI, T2WI, MRCP and dynamic enhanced MRI. The data were measured and statistical analysis was applied in four groups. Two radiologists assessed pancreatic duct diameter, pancreatic size, pancreatic cyst, pancreatic stone and pancreatic signal intensity on MRCP, T1-weighted and T2-weighted images. Pancreatic signal intensity were also measured on dynamic enhanced MR. Results Mean values of pancreatic signal intensity ratio on T1WI (rT1)in the pancreas were significantly reduced in patients with moderate and severe CP compared with volunteers.There was significant difference among four groups ( normal, 0. 98 ±0.27; mild, 0. 84 ±0. 12; moderate,0.81 ±0. 16; severe, 0.75 ±0.24). Mean values of pancreatic signal intensity ratio on T2WI (rT2) in the pancreas were no difference among four groups ( normal, 1.28 ± 0.3; mild, 1. 46 ± 0. 44, moderate, 1.46 ±0.55; severe, 1.76 ± 0.72). Pancreatic duct diameters were significantly increased in mild, moderate and severe CP groups [ mild (5.3 ± 2.4) mm; moderate ( 6.5 ± 3.3 ) mm; severe ( 8.1 ± 4.1 ) mm ] compared with patients without CP[ (2.0 ±0.6) mm; P < 0.01 ]. Severe degree of Cambridge classification was graded as mild in 4 (29%), moderate in 33 (89%), severe in 13 (93%). Pancreatic calcification was graded as mild in 2 ( 14% ), moderate in 11 (30%), severe in 5 (36%). Pancreatic pseudocyst was graded as mild in 0, moderate in 6 ( 16% ), severe in 3 (21.43%). Pancreatic parenchymal atrophy was graded as mild in 4 (29%), moderate in 22 (59%), severe in 10 (71%). They did not vary among CP groups. Parenchymal/arterial phase enhanced ratio (P/A) in the pancreas were significantly increased in patients with mild,moderate and severe CP (mild, 1. 10 ±0.08; moderate, 1.37 ±0.15; severe, 1.48 ±0.53) compared with patients without CP (0.88 ± 0.08, P < 0. 05 ). Significant correlation was present between the severity level of CP and the change of rT1, severe degree of Cambridge classification, the pancreatic duct diameter and P/A (r=0. 34, 0.41, 0. 62, - 0. 43; P < 0. 01 ). ROC analysis showed the presence of pancreatic duct diameters more than 2.5mm, rT1 less than 0. 8 and P/A more than 0. 8 had a sensitivity and specificity of diagnosing chronic pancreatitis of 94% and 79%, 90% and 48%, 95% and 47% respectively. Combined with the three variables, the specificity of diagnosing chronic pancreatitis can be improved to 95%.Conclusions T1-weighted, MRCP and dynamic enhanced MRI imaging can accurately evaluate the clinical severity of chronic pancreatitis. MRCP had the highest sensitivity and specificity, followed by T1-weighted and dynamic enhanced MRI imaging.
