The Pathology-Diffusion MRI Correlative Study of Diabetic Nephropathy Models
|School||Guangzhou Medical College|
|Course||Medical Imaging and Nuclear Medicine|
|Keywords||Kidney Magnetic resonance imaging Rats Diabetic nephropathy|
The purpose of making the rats with early diabetic nephropathy model, both kidneys with diffusion-weighted MR imaging (diffusion weighted imaging DWI), dynamic measurement of the apparent diffusion coefficient (apparent diffusion coefficient, ADC) values, pathology, urinary microalbuminuria The protein measurement results were compared to explore the value of the ADC value in the diagnosis of early diabetic nephropathy, and to lay the basis of imaging for clinical diagnosis. Materials and Methods 40 rats produced early diabetic nephropathy model (10 control rats and the model rats 30, model group rats were divided into diabetes four weeks group (G1), diabetes eight weeks group (G2 ) 10, diabetes 12 weeks (G3) 10 only). Model by intraperitoneal injection of STZ, control group injected with equivalent production diabetic nephropathy animal models citrate buffer. The models were successfully measured once every two weeks after the blood sugar and body weight. Respectively, at 4 weeks, 8 weeks and 12 weeks using 1.5T magnetic resonance imaging system application of echo-planar imaging (FFE-EPI) and the ordinary imaging sequence T1WI and T2WI rat kidney scan, diffusion gradient factor (b) were 0 s / mm ~~ 2,130 s / mm ~~ 2,260 s / mm ~ 2,390 s / mm to 2,300 s / mm to 2,500 s / mm ~~ 2,800 s / mm ~~ . Observed kidney morphology and signal change, dynamic measurements at different times of the ADC value and ADC map. MR scan is complete pathological examination of the kidneys, rat urine micro albumin (ALB) enzyme immunoassay urinary albumin determination. Whether there are differences between different groups using independent sample t test was used to compare the ADC value. ADC value measurements pathology and urinary micro albumin correlation analysis and multiple regression analysis, the comparison between any two whether there is a correlation. Results between different time period model group and the control group of blood glucose and body weight change results statistically significant difference (glucose: P lt; 0.05; weight: P lt; 0.05). MRI results, the control group 9 rat renal cortex (CO layer) ADC value (1.25 × 10 ~ 3 ± 101.27) μm ~ 2 / s; outer medulla, the outer layer (OS layer) ADC value (0.92 × 10 ~ 3 ± 138.86) μm ~ 2 / s; the outer medulla layer inner of (IS layer) ADC value (1.52 × 10 3 ± 302.47) μm to 2 / s; inner medullary layer (IM layer) ADC value (1.15 × 10 ~ 3 ± 228.22) μm ~ 2 / s. Group G1 and G2 5 rat renal parenchyma with the control group G2 group of rats with the G3 group rats the 7 renal parenchyma showing a clear four-layer structure, layers ADC values ??were: CO layer ADC value (1.32 10 to 3 ± 161.55) μm ~~ 2 / s; the OS layer ADC value (1.44 × 10 3 ± 304.39) μm to 2 / s; the the IS layer ADC value (1.84 × 103 ± 208.82) μm ~~ / s ; the IM layer ADC value (1.14 × 10 3 ± 421.61) μm to 2 / s. I G3 was a rat with the control group. Groups renal parenchyma layers ADC value of the CO layer G2 group with the control group the difference was statistically significant (P lt; 0.05); difference of the OS layer G3 group and the control group both with statistical significance (P lt; 0.05 ); the IS layer G3 group comparison with the control group, the difference was statistically significant (P lt; 0.05). Obvious diabetic nephropathy model group renal pathological changes: glomerular swelling, deformation, mesangial cell proliferation, glomerular basement membrane thickening, a statistical difference between the model group and the control group both pathological results significance (P lt; 0.05). The model group G3 urine microalbumin amount increased, a statistically significant difference between the results with the control group (P lt; 0.05). Pathology and urinary albumin measurement results with ADC values ??(CO OS layer) good correlation (R = 0.467). Conclusion magnetic resonance diffusion imaging and ADC value measurement results with pathological findings and urinary albumin measurement results have a good correlation ADC maps generated by the imaging MR DWI ADC value measurement can be observed in early diabetic nephropathy renal parenchyma The change has important value in the diagnosis of early diabetic nephropathy as early diabetic nephropathy conventional imaging diagnosis method.