In vivo evaluation of early renal damage in type 2 diabetic patients on 3.0 T MR diffusion tensor imaging

Abstract

AIMTo investigate the utility of renal diffusion tensor imaging (DTI) to detect early renal damage in patients with type 2 diabetes.METHODSTwenty-six diabetic patients (12 with microalbuminuria (MAU), and 14 with normoalbuminuria) and fourteen healthy volunteers were prospectively included in this study. Renal DTI on 3.0 T MR was performed, and estimated glomerular filtration rate (eGFR) was recorded for each subject. Mean cortical and medullary fractional anisotropy (FA) values were calculated by placing multiple representative regions of interest. Mean FA values were statistically compared among groups. Correlations between FA values and eGFR were evaluated.RESULTSBoth cortical and medullary FA were significantly reduced in diabetic patients compared to healthy controls (0.403 ± 0.064 vs 0.463 ± 0.047, P = 0.004, and 0.556 ± 0.084 vs 0.645 ± 0.076, P = 0.002, respectively). Cortical FA was significantly lower in diabetic patients with NAU than healthy controls (0.412 ± 0.068 vs 0.463 ± 0.047, P = 0.02). Medullary FA in diabetic patients with NAU and healthy controls were similar (0.582 ± 0.096 vs 0.645 ± 0.076, P = 0.06). Both cortical FA and medullary FA correlated with eGFR (r = 0.382, P = 0.015 and r = 0.552, P = 0.000, respectively).CONCLUSIONFA of renal parenchyma on DTI might serve as a more sensitive biomarker of early diabetic nephropathy than MAU.

Diffusion Tensor Imaging in Rat Models of Preclinical Diabetic Nephropathy: A Preliminary Study

“…FA is able to provide information about the diffusion direction and its degree at the same time. It has been shown that the FA values of the renal cortex and medulla are reduced in DN patients with or without microalbuminuria relative to those in normal healthy volunteers (6,15). Yan (5) found that the cortical FA value was significantly lower in early DN rats than in the NC group.…”

“…Diffusion tensor imaging (DTI) can apply motion-sensitive gradients in at least six directions to noninvasively evaluate the diffuse motion of water molecules. DTI (5,6) is a promising non-invasive technique that can assess renal function and pathology by qualitatively and quantitatively imaging three-dimensional diffusion of water molecules. DTI can not only describe the direction of diffusion of water molecules in tissues by fractional anisotropy (F A), but also describe the displacement degree of water molecules in tissues in the direction of diffusion sensitive gradient by apparent diffusion coefficient (ADC).…”