Study Of The Pancreatic Disease With Diffusion Weighted Imaging

Objective:To study the better way to measure apparent diffusion coefficient value of pancreatic disease with different b value combination.To evaluate the value of diffusion weighted imaging of ability to examine pancreatic focus of infection and qualitation to pancreatic disease. Methods:1. 45 patients (15 subjects with normal pancrease,15 normal liver and 15 pancreatic cancer)who underwent diffusion weighted imaging were studied.,using high and low b value combination.To measure and compare ADC value of organ and lesions. 2.20 patients with pancreatic cancer used diffusion weighted imaging (b =50,200,400sed/mm~2),normal T1WI and T2WI to examine. Calculated the different b value of pancreatic lesions.Compared the value of contrsast-to-noise rate(CNR)in conventional T1,T2 sequences.3. There were totally 96 subjects underwent DWI. They were 16 subjects as group control ,30 subjects chronic pancreatitis(including 9 subjects with lump type pancreatitis), 38 subjects pancreatic carcinoma,and 12 subjects pancreatic pseudocyst. DWI with b value = 0,500,1000mm~2 /sec was used.Results:1.The results from ADC value measurement between high b value difference and low b value difference in 3 class cases had no obvious statistic meanings(p>0.05).But high b value difference class has low fluctuation.2. there were statistical difference between t1,t2 and different b value except the value of 200 that t1 minus b value(P <0.05)3.The groups(which were pancreatic pseudocyst,pancreatic cancer,normal pancrease and chronic pancreatitis) each other had statistical significance (P<0.05).Conclusion:1. The results of low b value measurements were not as stable as the results of high b value measurements when using DWI. Otherwise anatomical structures showed more clearly when using low b value.2. The detection capabilities of pancreas lesion using diffusion-weighted magnetic resonance imaging is better than conventional t1,t2.3. DWI has a lot of clinical meanings through measuring ADC value to qualitate pancreatic disease.