Diagnostic performance of mDIXON-Quant imaging in assessing glomerulosclerosis severity for chronic kidney disease: a comparative study of R2* and fat fraction parameters

To compare two region-of-interest (ROI) measurement methods based on mDIXON-Quant for distinguishing healthy volunteers (HV), chronic kidney disease (CKD) patients with low (≤ 15%) and high (> 15%) glomerulosclerosis (GS), and establish a non-invasive auxiliary protocol. A total of 42 CKD patients and 25 HV underwent mDIXON-Quant MRI. CKD patients were stratified into low (n = 24) and high (n = 18) GS groups via renal biopsy. Two ROI methods were applied: Method 1 (cortex/medulla separation, 15–20 mm² circular ROIs at renal hilum, upper/lower poles) and Method 2 (whole-kidney contour tracing). R2* and fat fraction (FF) parameters were analyzed using ANOVA, LSD tests, and DeLong tests for diagnostic efficacy (AUC). R2* parameters (RcR2*, RR2*) showed significant differences across groups (P < 0.05), increasing with GS severity. LcR2* and RmR2* distinguished HV from high GS (P < 0.05), while LFF differentiated low vs. high GS (P < 0.05). Combining FF with R2* improved AUC from 0.685 to 0.877 (P < 0.05) for low/high GS discrimination. Method 1’s RcR2* (AUC = 0.957) and Method 2’s RR2* (AUC = 0.9) were most accurate for distinguishing high GS from HV, with no significant difference between them (P > 0.05). RcR2* outperformed medullary parameters (P < 0.05). The present study demonstrates that employing the Method 2(whole-kidney contour tracing) based on mDIXON-Quant technology enables auxiliary quantitative assessment of the severity of GS via the R2 parameter of the right kidney, thereby confirming its role as an adjunctive tool in GS evaluation.