TOPLINE:

Multiparametric MRI noninvasively detected age-related changes in kidney microstructure and function, showing significant declines in medullary T1 and T2* values and renal blood flow among healthy adults with advancing age.

METHODOLOGY:

• Researchers enrolled 46 healthy participants (mean age, 46.4 years; 25 women; serum creatinine level < 105 μmol/L; BMI < 25) to assess the impact of aging on renal microstructure and function using multiparametric MRI.
• Participants were divided into three age groups — 20-40 years (n = 18), 40-60 years (n = 16), and older than 60 years (n = 12) — with balanced sex distribution.
• Analysis included multiparametric MRI sequences at 3 Tesla comprising T1, T2, and T2* mapping, arterial spin labelling to measure renal blood flow, and intravoxel incoherent motion diffusion imaging.
• Cortical and medullary values for T1, T2, and T2* were measured, and corticomedullary ratios were calculated to assess relative differences in relaxation times.

TAKEAWAY:

• Medullary T1 relaxation times decreased significantly with age (correlation coefficient [r], -0.44; P < .01); older participants (age > 60 years) had significantly lower medullary T1 values (P = .03) and significantly higher corticomedullary ratios (P < .01) than younger participants (age, 20-40 years).
• T2* medullary values showed a significant age-related decline (r, -0.40; P < .01), particularly in older participants (P < .01). However, cortical and medullary T2 values and intravoxel incoherent motion diffusion parameters showed no significant age-related changes.
• Renal blood flow measured by arterial spin labelling showed a significant reduction with increasing age (r, -0.38; P < .01); younger participants (age, 20-40 years) had significantly higher values than older individuals (age, 40-60 years; P = .04).
• Age was an independent and significant predictor of T1 values (P < .01), T2* values (P < .01), and renal blood flow (P = .01).

IN PRACTICE:

"T1, T2*, and ASL [arterial spin labelling]-derived perfusion markers each reflect distinct aspects of renal aging: from microstructural remodeling (T1) to oxygenation decline (T2*) to vascular changes (ASL)," the authors wrote, highlighting the "complementary nature of these parameters" that, "strengthens the case for using multiparametric MRI as a tool to detect early subclinical renal impairment — even when conventional biomarkers remain within normal limits."

SOURCE:

The study was led by Toni Rabadi, Institute of Diagnostic and Interventional Radiology, University Hospital Zurich, Zurich, Switzerland. It was published online on August 17, 2025, in European Journal of Radiology.

LIMITATIONS:

The small cohort size and absence of histopathologic validation were key limitations, and larger studies are needed to further validate the study results.

DISCLOSURES:

This study did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors. The authors declared no conflicts of interest.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.