Background: Cerebral small vessel disease (CSVD) is a chronic disorder affecting small vessels within the brain, increasing the risk of stroke in patients with chronic kidney disease (CKD). Diffusion tensor imaging (DTI) is a newer quantitative method for diagnosing CSVD at an early stage of pathogenesis. Objectives: This study compares various DTI parameters in multiple white matter tracts of the brain in CKD patients undergoing maintenance hemodialysis with normal controls in the Indian population using the volume of interest (VOI) method. Additionally, it correlates these DTI parameters with each other at different locations to gain insights into the pathogenesis of CSVD. Methods: After obtaining institutional ethics approval, a cross-sectional study was conducted at a tertiary care hospital over one year (June 2022 to May 2023). The study comprised seventy-five patients in the hemodialysis group and twenty-five controls. All participants underwent MRI brain examinations on a 3 Tesla MRI scanner, and the four DTI parameters - fractional anisotropy (FA), axial diffusivity (AD), radial diffusivity (RD), and mean diffusivity (MD) - were reviewed for nine white matter tracts to evaluate statistical differences and correlations. Results: Fractional anisotropy was significantly decreased at anterior locations – corpus callosum genu (P = 0. 357 × 10-7), right anterior corona radiata (P = 0.001), and left anterior corona radiata (P = 0.45 × 10-5). In these locations, FA negatively correlated with RD (R = -0.7904, P < 0.00001), and RD was also significantly increased. Axial diffusivity was significantly increased at posterior locations in the corpus callosum splenium (P = 0.108 × 10-5) and left posterior corona radiata (P = 0.244 × 10-5). However, none of the four DTI parameters showed significant differences between hemodialysis patients and the control group for the subset of patients with normal routine brain MRI features. The intraclass correlation coefficients (ICCs) were high for all four DTI parameters for both patients (0.78 to 0.85) and controls (0.82 to 0.89). Conclusions: This study on CKD patients undergoing maintenance hemodialysis reveals significant differences in some DTI parameters in widespread white matter tracts of the brain using the VOI method, with acceptable to excellent interobserver agreement.
Read full abstract