The Value Of Virtual Touch Tissue Quantification Technique On Evaluating Type Of Diabetic Microangiopathy

BackgroundAcoustic Radiation Force Impulse(ARFI)is a non-invasive ultrasonic imaging technology for evaluating tissue elasticity,which measured the Shear Wave Velocity(SWV)though the tissue with the Virtual Tissue Quantification(VTQ)function,and then quantitatively assess tissue elasticity and hardness changes,the higher the SWV value,the harder the tissue,the poorer the elasticity.At present,ARFI has been applied to liver and kidney fibrosis grading maturely and so on.Diabetic microangiopathy is a common diabetic complication which mainly includes diabetic nephropathy,diabetic retinopathy and diabetic peripheral neuropathy.The typical pathological manifestations of diabetic microangiopathy consists of capillary basement membrane thickening and extracellular matrix protein synthesis.These changes can be found in arterioles of the retina,glomeruli,muscle,myocardium and skin.It is not certain,however,whether they can be present in diabetic pancreatic microvasculature Since diabetes mellitus is a type of chronic inflammation caused by nutrients and metabolic surplus that leads to pancreatic fibrosis,is there a link between microvascular complications and pancreatic fibrosis?Although ARFI has been applied to liver and kidney fibrosis grading maturely,due to the particularity of pancreatic biopsy,the study on the relationship between pancreatic SWV and pancreatic fibrosis has been limited.Currently,the VTQ technology is mainly applied in the differential diagnosis of normal pancreas,all kinds of pancreatitis and benign,malignant tumor.There is few literature reported on the studyabout diabetic pancreatic elasticity.ObjectiveThis study detected the pancreas SWV values of T2 DM patients and normal persons noninvasively.One hand to compare pancreatic shear-wave velocity(SWV)in subjects among the normal persons and those with and without diabetic microvascular complications;on the other hand,to study the factors that were associated with the value of SWV of pancreatic body in type 2 diabetic patients,and further to investigate the feasibility of VTQ in evaluating diabetic microangiopathy.MethodsThe diabetics group in this study is inpatient patients meeting the 1999 WHO diagnostic criteria of diabetes,a total of 115 cases.All patients were evaluated for diabetic microvascular complications.According to the presence of diabetic microvascular complications,all T2 DM patients were divided into two subgroups:those with complications(47 cases,Male 22,Females 25,and aged 36~81,with an average age of 56.72±9.43 years old)and those without complications(68 cases,Male39,Females 29,and aged 25~81,with an average age of 49.46±12.82 years old).The normal group is the volunteer selected randomly from the normal examination,a total of 115 cases(Male 63,Females 52,and aged 23~67,with an average age of49.24±11.46 years old).Record the height,the weight,the gender,and the age of each patient and calculate the BMI.All patients who are fasting for 8-12 hours are taken the elbow venous blood in the morning for fasting blood glucose,fasting C peptide,glycosylated hemoglobin,triglyceride,total cholesterol,high-density lipoprotein cholesterol and low-density lipoprotein cholesterol.This study used ACUSON S2000 color Doppler ultrasonic diagnostic instrument that was made in German SIEMENS company,equipped with VTQ and chosen 4C1 convex array probe.All checked inspections keep empty stomachs strictly more than8 hours,lying on the examining bed,fully exposed belly.At first,the conventional ultrasound examination was performed for each patient to observe the outline and essential echo of pancreas,measure the anteroposterior diameter of the head,body and tail of pancreas.And then start the VTQ mode of ARFI technology,measure the SWV value of head,body and tail of pancreas.SPSS19.0 statistical software was used to test the normal distribution of the experimental data.The differences between groups were compared by the Kruskal-Wallis test or one-way ANOVA of variance.For all patients with diabetes,Pearson or Spearman bivariate correlation analysis was performed to evaluate the correlation between the clinical parameters and pancreatic SWV.Multiple stepwise linear regression analysis was used to determine the contribution of various clinical factors to SWV in the pancreas.In control subjects,correlation between age and SWV was also calculated for comparison with that of patients with diabetes.A value of p<0.05 was considered statistically significant.Result1.Comparison of clinical data between the three groupsThere was significant difference between T2 DM patients with microvascular complications and those without microvascular complications and with normal control group(P < 0.05).There was no significant difference T2 DM patients with microvascular complications and normal controls(P > 0.05).In type 2 diabetes,there was a statistical difference in BMI and course of disease between with and without microvascular complications(P < 0.01).2.Comparison of laboratory test indexes between three groupsThe levels of FBG,HbA1 C,TG,TC,HDL-C and LDL-C in T2 DM with andwithout microvascular complications were statistically different from those in normal controls(P < 0.01).There was no significant difference in FBG,FCP,HbA1 C,TG,TC,HDL-C and LDL-C between with and without microvascular complications in type 2diabetes(P > 0.05).3.Comparison of pancreatic SWV value among groupsThe SWV of the head,tail and body of the T2 DM patients with and without microvascular complications were significantly higher than those of the normal controls(P < 0.01).In T2 DM patients,the SWV of pancreatic body with microvascular complications was higher than that without microvascular complications(P < 0.01),but there was no significant difference in the pancreatic SWV value between the head and the tail of the pancreas(P > 0.05).4.Association between SWV in pancreatic body and the various parameters in control subjects and patients with diabetes mellitus(1)Because there is a difference in age between the complication group and the without complication group and the control group,there is no relationship between the SWV value of the pancreas and the age(r =-0.13,P = 0.167).(2)The correlation between the SWV value of pancreatic body and various clinical parameters in T2DM: SWV of pancreatic body was positively correlated with age,course of disease,TC and microvascular complications.(3)Further multiple stepwise linear regression showed that microvascular complications,age and TC were the key parameters influencing the SWV of pancreatic body.ConclusionThe increase of SWV in pancreatic body in patients with T2 DM was significantly associated with microvascular complications,and SWV of pancreatic body had some value in assessing microvascular complications of diabetes.