The value of diffusion kurtosis imaging in early diagnosis of diabetic nephropathy model in Guangxi Bama mini pig

Abstract

Objective To investigate the value of diffusion kurtosis imaging (DKI) in diagnosing early diabetic nephropathy. Methods Twelve pigs were divided into the experimental group (7 pigs) and the control group (5 pigs), used the random number table method. The experimental group was fed with high-fat high-sugar diet,and then repeatedly injected small doses (50 mg/kg) of Streptozotocin (STZ) through the ear vein. Meanwhile,the control group was fed with normal diet and injected with the same dose of citric acid-sodium citrate buffer solution.After the type 2 diabetes was established successfully, T1WI, T2WI and DKI sequence imaging were performed every month for 2 pigs from the experimental group and the control group,respectively.Mean kurtosis(MK), axial kurtosis (K∥), radial kurtosis (K⊥), fractional anisotropy (FA) and mean diffusivity(MD) were measured on the pseudo-color map of the post-processing workstation. fasting blood glucose(GLU),insulin (INS),renal function, urine routines and random albumin creatinine ratio(RACR) were measured before MRI scan. Specimens from bilateral kidneys were taken for pathological examination after MRI scan. The paired t test was used to compare the parameter values of the cortex and medulla.Independent sample t test was used tocompare the parameter values of the experimental group and the control group. Results In the experimental group,the MK, FA values of medulla were 0.66±0.07 and 0.19±0.04, the MK, FA values of cortex were 0.60±0.06 and 0.16±0.03.In the control group,the MK, FA values of medulla were 0.59±0.03 and 0.20±0.04, the MK, FA values of cortex were 0.53±0.03 and 0.17±0.04.The MK and FA values of medulla were increased compared with the cortex and the difference were statistically significant (P 0.05). Conclusion DKI sequencehas certain value in the diagnosis of early diabetic nephropathy,and to some extent reveals the pathological change in early diabetic nephropathy. Key words: Diabetic nephropathies; Magnetic resonance imaging; Disease models, animal