Assessment of the Added Value of Intravoxel Incoherent Motion Diffusion‐Weighted MR Imaging in Identifying Non‐Diabetic Renal Disease in Patients With Type 2 Diabetes Mellitus.

Background: Identification of non‐diabetic renal disease (NDRD) in patients with type 2 diabetes mellitus (T2DM) may help tailor treatment. Intravoxel incoherent motion diffusion‐weighted imaging (IVIM‐DWI) is a promising tool to evaluate renal function but its potential role in the clinical differentiation between diabetic nephropathy (DN) and NDRD remains unclear. Purpose: To investigate the added role of IVIM‐DWI in the differential diagnosis between DN and NDRD in patients with T2DM. Study Type: Prospective. Population: Sixty‐three patients with T2DM (ages: 22–69 years, 17 females) confirmed by renal biopsy divided into two subgroups (28 DN and 35 NDRD). Field Strength/Sequence: 3 T/ T2 weighted imaging (T2WI), and intravoxel incoherent motion diffusion‐weighted imaging (IVIM‐DWI). Assessment: The parameters derived from IVIM‐DWI (true diffusion coefficient [D], pseudo‐diffusion coefficient [D*], and pseudo‐diffusion fraction [f]) were calculated for the cortex and medulla, respectively. The clinical indexes related to renal function (eg cystatin C, etc.) and diabetes (eg diabetic retinopathy [DR], fasting blood glucose, etc.) were measured and calculated within 1 week before MRI scanning. The clinical model based on clinical indexes and the IVIM‐based model based on IVIM parameters and clinical indexes were established and evaluated, respectively. Statistical Tests: Student's t‐test; Mann–Whitney U test; Fisher's exact test; Chi‐squared test; Intraclass correlation coefficient; Receiver operating characteristic analysis; Hosmer–Lemeshow test; DeLong's test. P < 0.05 was considered statistically significant. Results: The cortex D*, DR, and cystatin C values were identified as independent predictors of NDRD in multivariable analysis. The IVIM‐based model, comprising DR, cystatin C, and cortex D*, significantly outperformed the clinical model containing only DR, and cystatin C (AUC = 0.934, 0.845, respectively). Data Conclusion: The IVIM parameters, especially the renal cortex D* value, might serve as novel indicators in the differential diagnosis between DN and NDRD in patients with T2DM. Evidence Level: 2 Technical Efficacy: Stage 2 [ABSTRACT FROM AUTHOR]