Research Of Pancreatic MSCT Perfusion Characteristics And Its Influencing Factors In Liver Cirrhosis

Purpose: To study the correlation between the width of portal vein in portal hypertension in liver cirrhosis and pancreatic perfusion parameters.Materials and Methods:1. Collect 118 cases in which patients received enhancing scan of Multi-slices Spiral CT, MSCT on upper abdominal and insulin perfusion in our hospital from June, 2012 to March, 2013, with an exclusion of 2 cases in which image diagnosis was affected due to patients’ incapacity of holding breath and wide-range of breath, and another 2 cases due to medicine permeation. A total of 114 cases have been chosen. Based on inclusion criteria, they are randomly divided into Normal Control Group including 48 cases, and cirrhotic portal hypertension Group including 66 cases. Pancreatic CT perfusions are conducted separately.2. The U.S. GE Light Speed VCT 128 spiral CT is used to conduct conventional epigastrium scan on subjects; Scanning conditions: 120 k V, 200 m A, 1.0s/r, filter function FC10, thickness of collection layer 0.625mm×64mm, thickness of re-construction layer 5mm, reconstruction interval 5mm, matrix 512×512, and thread pitch 0.984.3. Determine the scanning range of pancreatic perfusion with plain scanning images. Inject 50 ml nonionic contrast agent(300 mg I/ml) with double-syringe power injector in the vein at a speed of 5.0ml/s. After the injection of contrast agent, inject 20 ml normal saline at the same speed to wash the pipe. Perfusion scanning parameters: 80 k V, 150 m A, 1.0s/r, matrix 512×512, collecting layer thickness 0.625mm×64mm, interval 0mm, pitch 0.984, rotating time 1s, coverage area of detector 40 mm, delay time 5s, interval time 1s, data acquisition time 52 s, total exposure time 26 s, 8 images would be generated of every exposure, and in all 208 perfusion images would be created. After the perfusion, inject 50~60ml contrast medium at a speed of 3.0ml/s to complete the regular enhancement scanning.4. The original images of the perfusion are transmitted to GE AW4.5 workstation and the data are processed using the pancreatic perfusion software package Body Pancreas(deconvolution) of the CT Perfusion 4(Version V4.42). The pseudo-color images of the pancreas instillation CT are obtained after the process of the workstation. The perfusion parameters of multi points in the interested areas of the pancreatic tissues are read, recorded and statistically analyzed.5. Measure the width of the portal vein during enhanced scanning of the portal vein in the PACS workstation. The measuring point is chosen at about 1.5~2.0 cm above the joint of vein and splenic vein on the mesentery. The same places are measured three times respectively, their average value recorded and statistics collected.Results: In normal control group, the BF, BV, PS, MTT and PV are(120.20±27.69) ml·100g-1·min-1,(25.32±5.01)ml·100g-1,(18.31±22.22) ml·100g-1·min-1,(13.66±2.78)s and(10.93±1.50)mm respectively; in the group of cirrhotic portal hypertension, the BF, BV, PS, MTT and PV are(98.04±26.00) ml·100g-1·min-1,(21.23±8.28)ml·100g-1,(22.40±26.47) ml·100g-1·min-1,(16.10±5.43)s and(14.64±2.36)mm respectively. The differences between BF, BV, MTT and PV in the two groups have statistical significance(P<0.05), while the PS does not have statistical significance. There is correlation between PV and BF, BV in the pancreas’ perfusion parameters(P<0.05), and the correlation coefficient γ are respectively-0.328 and-0.272.There is no linear correlation existing among MTT, PS and PV. In cirrhotic portal hypertension, PV=12.92 mm is the threshold value affecting Pancreatic perfusion, whose sensitivity and specificity are respectively 78.5% and 93.6%, and the area under the curve is 93.6%.Conclusion: Under the condition of cirrhotic portal hypertension, there is a negative correlation between the width of portal vein and normal pancreatic perfusion(BF and BV), and the threshold value of the width is 12.92 mm.Purpose: Discuss the manifestation and influencing factors of pancreas MSCT perfusion imaging under the condition of liver cirrhosis.Materials and methods:1. Collect 191 cases that had upper abdominal scanning enhanced in multi-spiral CT and pancreatic perfusion in our hospital from December 2012 to October 2014. According to the inclusion and exclusion criteria, the cases are divided into the normal control group of 48 cases and cirrhotic portal hypertension group of 143 cases, among which there are 119 cases of virus B posthepatitic cirrhosis, 8 cases of alcoholic cirrhosis, 11 cases of biliogenic cirrhosis, 2 cases of autoimmune cirrhosis, and 3 cases of genetic cirrhosis.2. The U.S. GE Light Speed VCT 128-layer spiral CT is used to conduct conventional epigastrium scan on subjects; Scanning conditions: 120 k V, 200 m A, 1.0s/r, filter function FC10, thickness of collection layer 0.625mm×64mm, thickness of re-construction layer 5mm, reconstruction interval 5mm, matrix 512×512, and thread pitch 0.984.3. Determine the scanning range of pancreatic perfusion with plain scanning images. Inject 50 ml nonionic contrast agent(300 mg I/ml) with double-syringe power injector in the antecubital vein at a speed of 5.0ml/s. After the injection of contrast agent, inject 20 ml normal saline at the same speed to wash the pipe. Perfusion scanning parameters: 80 k V, 150 m A, 1.0s/r, matrix 512×512, collecting layer thickness 0.625mm×64mm, interval 0mm, pitch 0.984, rotating time 1s, coverage area of detector 40 mm, delay time 5s, interval time 1s, data acquisition time 52 s, total exposure time 26 s, 8 images would be generated of every exposure, and in all 208 perfusion images would be created. After the perfusion, inject 50~60ml contrast medium at a speed of 3.0ml/s to complete the regular enhancement scanning.4. The original images of the perfusion are transmitted to GE AW4.5 workstation and the data are processed using the pancreatic perfusion software package Body Pancreas(deconvolution) of the CT Perfusion 4(Version V4.42). The pseudo-color images of the pancreas instillation CT are obtained after the process of the workstation. The perfusion parameters of multi points in the interested areas of the pancreatic tissues are read, recorded and statistically analyzed.Results:1. The comparison of pancreatic perfusion parameters between liver cirrhosis group and normal control group: using independent sample T test, the pancreatic perfusion parameters BF, BV, MTT values between the two groups have statistical significance(P<0.05). BF, BV in liver cirrhosis group are lower than those in normal control group. while MTT in the liver cirrhosis group are higher than those in normal control group. PS has no statistical significance(P>0.05).2. The comparison among the value changes of the perfusion parameters of each part of the pancreas after liver cirrhosis: the perfusion parameter values of each part of the pancreas after liver cirrhosis: the differences among BF, BV, PS and MTT show no statistical significance(P>0.05).3. The comparison of the differences of parameter values of pancreatic perfusion within different Child-Pugh Classification in the group of cirrhosis: among three groups, the differences of BF and BV have statistical significance(P<0.05), while PS and MTT have no statistical significance; the comparison between two shows that the BF and BV differences in two arbitrary groups have statistically significant(P<0.05). With the increasing impairment of liver function, BF and BV differences gradually decrease.4. The comparison of the differences of parameter values of pancreatic perfusion among the subgroups with different volumes of ascites in the cirrhosis group: the BF, BV and MTT differences among the three groups all have statistical significance(P<0.05), among which the differences of BF and BV between the group without ascites and the group with a small amount of ascites have statistical significance(P<0.05), and with the increase of ascites, BF and BV decreases; the differences of BF and BV between the ascites group with a small amount and those with a medium to large amount have no statistical significance(P>0.05); the differences of MTT between group without the ascites and the ascites group with a medium to large amount have statistical significance(P<0.05).5. The comparison of the differences of parameter values of pancreatic perfusion between the groups of liver cirrhosis with or without collateral circulation: the BF differences between the two groups have statistical significance, while BV, PS, MTT differences have no statistical significance(P>0.05). The BF value of the group with collateral circulation is lower than that of the group without collateral circulation.Conclusions: Under the liver cirrhosis condition, the pancreas microcirculation disturbance and the pancreatic perfusion amount reduce. The main influencing factors include the degree of the liver function damage, the ascites amount and the opening situation of collateral circulation.