In vivo wideband MR elastography for assessing age-related viscoelasticity changes of the human brain
Schattenfroh J, Meyer T, Aghamiry HS, Jaitner N, Fedders M, Görner S, Herthum H, Hetzer S, Estrella M, Flé G, Steinmann P, Guo J, Sack I (2026)
Publication Type: Journal article
Publication year: 2026
Journal
DOI: 10.1016/j.actbio.2026.02.002
Abstract
Magnetic Resonance Elastography (MRE) noninvasively maps brain biomechanics and is highly sensitive to alterations associated with aging and neurodegenerative disease. Most implementations use a single frequency or a narrow frequency band, limiting the analysis of frequency-dependent viscoelasticity parameters. We developed a dual-actuator wideband MRE (5-50 Hz) protocol and acquired wave fields at 13 frequencies in 24 healthy adults (young: 23-39 years; older: 50-63 years). Shear wave speed (SWS) maps were generated as a proxy for stiffness, and SWS dispersion was modeled using Newtonian, Kelvin-Voigt, and power-law rheological models. Whole-brain stiffness declined with age, with the strongest effect observed at low frequencies (5-16 Hz: -0.24%/year; p = 0.038) compared with mid (20-35 Hz: -0.12%/year; p = 0.040) and high frequencies (40-50 Hz: -0.10%/year; p = 0.123). Compared to older brains, younger adults showed 8.96% higher baseline stiffness in the power-law model (p = 0.013) and 8.15-8.39% higher viscosity according to the Newtonian and Kelvin-Voigt model (p ' 0.05). White and cortical gray matter exhibited similar age-related decreases, while deep gray matter showed an increase in the power-law exponent (+0.001/year; p = 0.046), suggesting a transition toward more fluid-like properties associated with aging. Wideband MRE revealed frequency-dependent and region-specific biomechanical alterations with aging, with the strongest effects observed at low frequencies. Extending brain MRE into the low frequency regime potentially enhances sensitivity to solid-fluid interactions. Therefore, low frequency MRE may serve as an early biomechanical marker of microstructural brain changes due to aging and neurodegeneration. Statement of Significance Magnetic Resonance Elastography (MRE) is a noninvasive imaging modality that quantifies the mechanical properties of brain tissue. Conventional approaches are typically restricted to single or narrow vibration frequency ranges, limiting their ability to characterize frequency-dependent viscoelastic behavior. In this study, we establish a wideband MRE framework spanning 5-50 Hz and apply it in vivo to healthy adults across different age groups. Our results demonstrate that age-related brain softening is most pronounced at low frequencies, indicating sensitivity to microstructural alterations and potentially enhancing sensitivity to fluid-solid interactions. These findings highlight diagnostic potential of low frequency MRE for advancing biomechanical biomarkers of brain aging and for future applications in early detection of neurodegenerative disease.
Authors with CRIS profile
Involved external institutions
Germany (DE)How to cite
APA:
Schattenfroh, J., Meyer, T., Aghamiry, H.S., Jaitner, N., Fedders, M., Görner, S.,... Sack, I. (2026). In vivo wideband MR elastography for assessing age-related viscoelasticity changes of the human brain. Acta Biomaterialia. https://doi.org/10.1016/j.actbio.2026.02.002
MLA:
Schattenfroh, Jakob, et al. "In vivo wideband MR elastography for assessing age-related viscoelasticity changes of the human brain." Acta Biomaterialia (2026).
BibTeX: Download