Multiparametric
MR
Imaging for Detecting Early Chronic Kidney Disease and Grading Chronic Pathological Changes
Chengli Gu, Aoran Yang, Yang Zheng, Minghui Zhou, Wenjuan Li, Chen Zhang, Bernd Kühn, Xiaomei Liu, Xiufang Ren, Xue Li, Yu Shi ABSTRACT
Background
Conventional renal function markers, such as estimated glomerular filtration rate (eGFR), often fail to reflect occult renal parenchymal injury in early‐stage chronic kidney disease (CKD). Renal biopsy is invasive, limiting longitudinal monitoring. Reliable noninvasive methods for early CKD detection and chronicity assessment are lacking.
Purpose
To evaluate 3D MR elastography (3D‐MRE), arterial spin labeling (ASL), and intravoxel incoherent motion diffusion‐weighted imaging (IVIM‐DWI) for detecting early CKD and grading its chronic changes.
Study Type
Prospective.
Subjects
96 CKD patients with renal biopsy (44 ± 13 years, 55 men) and 30 healthy controls (43 ± 15 years, 18 men).
Field Strength/Sequence
3.0 T; multifrequency (60, 90, and 120 Hz) 3D vector MRE, pseudo‐continuous arterial spin labeling (pCASL), and multi‐ b ‐value (0–2000 s/mm 2 ) IVIM‐DWI.
Assessment
MRE‐derived renal stiffness (RS), ASL‐derived renal blood flow (RBF), and IVIM‐derived true diffusion coefficient (D), pseudodiffusion coefficient (D*), perfusion fraction (f), and apparent diffusion coefficient (ADC) were measured. CKD was staged from 1 to 5 according to eGFR, with Stages 1–2 defined as early CKD. Chronic changes were graded by chronicity score (CS), with CS > 4 indicating moderate‐to‐severe chronic changes.
Statistical Tests
Mann–Whitney U test, Kruskal–Wallis test with Bonferroni correction, intraclass correlation coefficients (ICC), Bland–Altman analysis, Spearman's rank correlation, univariable and multivariable logistic regression, area under the receiver operating characteristic curve (AUC), and DeLong's test. p < 0.05 was considered significant.
Results
The combined entire RS at 90 Hz (ERS@90) and the entire D achieved the highest AUC for distinguishing healthy controls from early CKD, significantly outperforming eGFR (AUC = 0.87 vs. 0.59). In early CKD, ERS@90 was the only independent discriminatory variable of moderate‐to‐severe chronic changes, significantly outperforming eGFR (AUC = 0.86 vs. 0.62).
Data Conclusion
3D‐MRE showed promise for noninvasive detection of early CKD and for identifying moderate‐to‐severe chronic changes.
Evidence Level
1.
Technical Efficacy
Stage 2.