Quantitative Analysis Of The Correlation Between Pancreatic Microcirculation And Impaired Glucose Tolerance And Type 2 Diabetes Mellitus By Dynamic Contrast-enhanced MRI

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QUANTITATIVE CHARACTERISTICS OF DCE-MRI IN NORMAL ADULT PANCREASObjective: To investigate the characteristics of quantitative parameter volume conversion(Ktrans),extracellular space volume ratio(Ve)and plasma volume ratio(Vp)of normal adult pancreatic dynamic contrast enhanced magnetic resonance imaging(DCE-MRI)between different sex,age and different parts of the pancreas in normal adults.Method:According to the inclusion and exclusion criteria,90 healthy volunteers were divided into young men(17 men,13 women,28-44 years of age,35 years of age),middle age groups(13 men,17 women,45-58 years of age,53 years of age)and the elderly group(15 men and women,60-74 years of age and median age 66 years)).All volunteers' informed consent was obtained and approved by the clinical trial ethics committee ofthe hospital.All the volunteers used the 3.0T superconducting magnetic resonance scanner for the pancreatic DCE-MRI examination.After the scan was completed,the DCE-MRI dynamic enhanced image was introduced into the Omni-Kinetics software(GE healthcare,China)for post-processing.The aorta was selected manually as the input artery to obtain the arterial input function(AIF).The pancreatic head,the pancreatic neck,the pancreas body and the tail of the pancreas were selected as the region of interest(ROI),and the Extended Tofts linear model was used to obtain quantitative parameter volume conversion(Ktrans),extracellular space volume ratio(Ve)and plasma volume ratio(Vp).SPSS 24.0 software was used for statistical analysis: the measurement data in the test data were expressed by mean±standard deviation.Two independent sample t tests were used to test the hypothesis,and the variance homogeneity test was selected in t test and t'test according to the variance homogeneity test.The data of different age groups and different parts of the pancreas were tested by variance analysis or rank sum test according to the difference of homogeneity of variance.The difference of P< 0.05 was statistically significant.Results:(1)The Ktrans values of DCE-MRI quantitative parameters in the different parts of the normal adult pancreas(head,neck,body and tail)were 0.0621±0.0025,0.0618±0.0026,0.0616±0.0021 and 0.0617±0.0025,respectively,and the Vp values were 0.2462±0.0022,0.2454±0.0022,0.2455±0.0021 and 0.2452±0.0019.the Vp values were 0.6129±0.0235,0.6107±0.0232,0.6088±0.0227 and 0.6092±0.2383.The difference of Ktrans value was not statistically significant(F=0.697,P=0.554);the difference of Ve was not statistically significant(F=0.570,P=0.635),but the difference in Vp was statistically significant(F=3.821,P=0.010),and the Vp value of the head of the pancreas was higher than that of the pancreatic neck,the pancreas body and the tail of the pancreas(P <0.05).(2)The normal adult male and female pancreas DCE-MRI quantitative parameter Ktrans male was 0.6221±0.0023,the female was0.6205±0.0023,the difference was not statistically significant(P=0.745),Ve male was 0.6112±0.0207,the female was 0.6086±0.0231,the difference was not statistically significant(P=0.584),the VP value was0.2475±0.0020,and the female was 0.2474.There was no significant difference between the 0.0023 and the difference(P=0.946).(3)The DCE-MRI quantitative parameters Ktrans of the pancreas in normal adults(young,middle-aged and elderly)were 0.0624±0.0026,0.0621±0.0022 and0.0619±0.0022,respectively,and there was no significant difference(F=0.351,P=0.705).and Vp was 0.2473±0.0022,0.2474±0.0023,0.2477±0.0027,and no statistical significance.(F=0.271,P=0.764).The Ve values were 0.6077±0.0209,0.5989±0.0192,and 0.6231 + 0.0218 respectively.The difference was statistically significant(F=11.754,P=0.000),and the Ve value of the pancreas in the elderly group was higherthan that in the middle age group and the young group.Conclusion:(1)There was no significant difference in DCE-MRI quantitative parameters between Ktrans and Ve in different parts of the pancreas of normal adults(head,neck,body and tail).The Vp values in different parts of the pancreas were different,and the Vp in the head of pancreas was higher than that of the pancreatic neck,the pancreas body and the tail of the pancreas.(2)There was no significant difference in DCE-MRI quantitative parameters of Ktrans,Ve and VP between normal adult male and female pancreas.(3)There was no significant difference in Ktrans and Vp between normal adults and different age groups.Ve values were different,and the Ve value in the elderly group was higher than that in the middle-aged group and the young group.(4)There is no gender difference in quantitative parameters of pancreas DCE-MRI,but there are some differences in age and location of pancreas.PART ? QUANTITATIVE ANALYSIS OF PANCREATIC DCE-MRI AND PANCREATIC MICROCIRCULATION IN PATIENTS WITH IMPAIRED GLUCOSE TOLERANCE AND TYPE 2 DIABETES MELLITUSObjective: The dynamic contrast enhanced magnetic resonance imaging(DCE-MRI)quantitative parameter volume conversion(Ktrans),extracellular space volume ratio(Ve)and plasma volume ratio(Vp)were used to assess the pancreatic microcirculation in normal population,impaired glucose tolerance and type 2 diabetic patients and to analyze their differences.Method:According to the inclusion and exclusion criteria,30 people(15 men,15 women,age 45-57 years,median age 50 years)and 30 people in type 2 diabetes group were collected in our hospital from August 2015 to December 2017.The course of disease < 10 years 15,8 men,7,age 51-72,middle age,63 years.The process is more than 10 years of 15,9 males,6females,age 53-71 years,median age 64 years).Another 30 normal volunteers were selected as control group(15 males,15 females,age 38-52 years,median age 45 years).All the volunteers used the 3.0T superconducting magnetic resonance scanner for the pancreatic MRI-DCE examination.After the scan was completed,the dynamic enhanced image of MRI was introduced into the Omni-Kinetics software for post-processing.The aorta was selected manually as the input artery to obtain the arterial input function AIF.The position of the pancreas was determined by MRI scan and enhanced image,and the whole pancreas was taken as a region of interest,and the blood vessels and fatty infiltration areas were avoided.The quantitative parameter volume conversion rate(Ktrans),extracellular space volume ratio(Ve)and plasma volume ratio(Vp)were obtained by using the Extended Tofts linear model.The average was measured 3 times per volunteer.SPSS 24.0 software was used for statistical analysis.The normal data and homogeneity test of Levene are used to measure data in experimental data.The independent samples t test was used for comparison between the groups,and the measurement data was expressed by±s.Logistic regression analysis and ROC curve were made for the factors with statistical difference,P < 0.05,the difference was statistically significant.Results:(1)The Ktrans value of DCE-MRI in type 2 diabetic group and impaired glucose tolerance group was higher than that of control group,and Vp value was lower than that of control group,the difference was statistically significant(P=0.000),while Ve value was higher than that of control group,but there was no statistical difference(P > 0.05).(2)Between the two groups,there was a significant difference between the two groups of Ktrans and Vp in different populations,P < 0.05.According to these two groups of values,LSD test showed that there was a difference between the control group and the impaired glucose tolerance group(P=0.036),and there was a difference between the impaired glucose tolerance group and the type 2 diabetes group(P=0.044),and the Vp value was different between the control group and the impaired glucose tolerance group(P=0.034),in the impaired glucose tolerance group and type 2diabetes mellitus.There was a difference between the disease groups(P=0.021).(3)In 30 patients with type 2 diabetes,the Ktrans and Ve values of n=15 were 1.0822±0.2244 and 0.8958±0.2275,compared with Ktrans and Ve(0.1571±0.0352,0.1269±0.0399)in the course of the disease < 10 years >(P=0.032 and P=0.037).The Vp value of patients with a duration of more than 10 years was 0.0634 + 0.0165,which was significantly lower than that of patients with a duration of less than 10 years(0.0566±0.0185),with no significant difference(P=0.298).(4)Logistic regression analysis of DCE-MRI quantitative parameters in the impaired glucose tolerance group,the area under the ROC curve of Ktrans and Vp was 0.652(95% confidence interval 0.514-0.791)and 0.682(95% confidence interval 0.547-0.817);when Ktrans was greater than1.133,its sensitivity to impaired glucose tolerance pretest was 30%,and the specificity was 100%;when Vp.When the value is less than 0.098,the sensitivity of predicting impaired glucose tolerance is 96.7%,and the specificity is 36.7%.Conclusion:(1)The Ktrans and Ve values of DCE-MRI in diabetic group and IGT group were higher than those in control group,and Vp value decreased.(2)Pancreatic endothelial cells have been damaged to varying degrees in the stage of impaired glucose tolerance and pancreatic microcirculation disorder.It is possible to try to delay the progression of diabetes by repairing endothelial cells and improving the microcirculation of the pancreas.(3)DCE-MRI quantitative parameters Ktrans and Vp have higher sensitivity and specificity for predicting impaired glucose tolerance.(4)In diabetic patients over 10 years,the injury of pancreatic endothelium increased,and the permeability of blood vessels increased further,and the volume ratio of plasma decreased.(5)DCE-MRI quantitative analysis may have potential value in monitoring and predicting new drugs for type 2 diabetes.PART ? EVALUATION OF PANCREATIC BETA CELL FUNCTION IN PATIENTS WITH IMPAIRED GLUCOSE TOLERANCE BY HYPERGLYCEMIC CLAMP TECHNIQUE AND DCE-MRIObjective: In this study,high glucose clamp technique was used to observe the characteristics of insulin secretion and insulin sensitivity in normal people and people with impaired glucose tolerance,and the correlation analysis with the results of DCE-MRI quantitative parameters in second parts of the pancreas was used to evaluate the evaluation of pancreatic microcirculation and high glucose clamp technique to evaluate the function of islet beta cells by DCE-MRI.Method:The outpatient and inpatient patients in the Inner Mongolia Autonomous Region people's Hospital from August 2015 to December2017 were selected as the subjects(consistent with the subjects of the normal group and the impaired glucose tolerance group in the second part of the study).There were 30 cases of impaired glucose tolerance group(group IGT): male 15,female 15,age 45 year old-57,middle age 50 years,body mass index(body mass index,BMI)26.33-30.21 kg / m~2,average27.56±1.39 kg / m~2.In the control group(NC),there were 30 cases: 15 males and 15 females,aged 38-52 years,median age 45 years,and BMI24.82 to 28.93 kg / m~2,averaging 26.73±1.32 kg / m~2.The above group OGTT(oral glucose tolerance test)and blood lipid level were normal,and the diabetes,endocrine system diseases,liver and kidney diseases were eliminated.The drugs that affected insulin secretion and sensitivity were not used 2 weeks before the trial.All the subjects performed the Hyperglucose clamp test to calculate the related parameters,1PH(insulin first phase secretion),2PH(insulin second phase secretion),Ins120-150(insulin maximum secretion)and ISI(insulin sensitivity index).The correlation between the parameters and the second part contents of pancreas DCE-MRI quantitative parameters was analyzed.The measurement data were expressed in the range of±s or median(range).The non normal distribution data were analyzed after the logarithmic conversion.The single factor analysis of variance was used among the multiple groups.The difference was statistically significant with the difference of P<0.05.Results:(1)High glucose clamp technique was used to obtain the first phase secreting of insulin,second phase secretion and the maximum insulin secretion under exogenous glucose stimulation.The results showed that the1 PH in the IGT group was 226.8±93.4m IU/L,the 1PH in the NC group was246.7±71.0m IU /L,and the IGT group was lower than the NC group.The difference was significantly higher than that in the IGT group(61.2±18.2),and the difference was statistically significant.In group NC(79.5± 11.8)m IU/L,the difference was statistically significant(P=0.000).(2)ISI in group IGT was 11.79±3.02,ISI in group NC was 18.88±5.04,IGT group was significantly lower than NC group,the difference was statistically significant(P=0.000).(3)The parameters of high glucose clamp test 2PH,Ins120-150,ISI and DCE-MRI quantitative analysis parameters Ktrans,Ve and Vp were analyzed with Pearson correlation,and the results showed that Ktrans and2 PH were positively correlated(r=0.398,P=0.037),Ktrans and Ins120-150 were positively correlated(r=0.406,P=0.040),Ktrans and ISI were positively correlated(r=0.408,P=0.008);There was a negative correlation between Vp and 2PH(r=0.405,P=0.033),and Vp was negatively correlated with Ins120-150(r=0.393,P=0.009),and Vp was positively correlated with Ins120-150(r=0.395,P=0.005).There is no correlation between Ve and 2PH,Ins120-150 and ISI(P=0.408,P=0.415,P=0.749).Conclusion:(1)There was an obvious increase in insulin resistance and compensatory insulin secretion in people with impaired glucose tolerance,and the insulin secretion curve was abnormal in the high glucose clamp test.(2)High glucose clamp technique can accurately reflect the changes of insulin biphasic secretion in people with impaired glucose tolerance.Early detection of beta cell dysfunction can be used to further study the pathophysiological changes and pathogenesis of impaired glucose tolerance.(3)1PH,2PH and Ins120-150 in high glucose clamp test were correlated linearly with DCE-MRI quantitative parameters Ktrans and Vp in IGT group.(4)Both the high glucose clamp test and DCE-MRI can better evaluate the microcirculation of the pancreas in the people with impaired glucose tolerance,and the early and potential islet beta cell dysfunction can be found.