Age- and gender-related differences in brain tissue microstructure revealed by multi-component T2 relaxometry

• Published in: Neurobiology of aging 2021-10, Vol.106, p.68-79
• Main Authors: Canales-Rodríguez, Erick Jorge, Alonso-Lana, Silvia, Verdolini, Norma, Sarró, Salvador, Feria, Isabel, Montoro, Irene, Garcia-Ruiz, Beatriz, Jimenez, Esther, Varo, Cristina, Albacete, Auria, Argila-Plaza, Isabel, Lluch, Anna, Bonnin, C. Mar, Vilella, Elisabet, Vieta, Eduard, Pomarol-Clotet, Edith, Salvador, Raymond
• Format: Article
• Language: English
• Subjects: Aging; Brain; Multi-exponential relaxation; Myelin water fraction; Tissue Microstructure
• ISSN: 0197-4580; 1558-1497
• DOI: 10.1016/j.neurobiolaging.2021.06.002

In spite of extensive work, inconsistent findings and lack of specificity in most neuroimaging techniques used to examine age- and gender-related patterns in brain tissue microstructure indicate the need for additional research. Here, we performed the largest Multi-component T2 relaxometry cross-sectional study to date in healthy adults (N = 145, 18−60 years). Five quantitative microstructure parameters derived from various segments of the estimated T2 spectra were evaluated, allowing a more specific interpretation of results in terms of tissue microstructure. We found similar age-related myelin water fraction (MWF) patterns in men and women but we also observed differential male related results including increased MWF content in a few white matter tracts, a faster decline with age of the intra- and extra-cellular water fraction and its T2 relaxation time (i.e. steeper age related negative slopes) and a faster increase in the free and quasi-free water fraction, spanning the whole grey matter. Such results point to a sexual dimorphism in brain tissue microstructure and suggest a lesser vulnerability to age-related changes in women. [Display omitted]