Age- and gender-related differences in brain tissue microstructure revealed by multi-component T2 relaxometry
Erick J. Canales‐Rodríguez, Sílvia Alonso-Lana, Norma Verdolini, Salvador Sarró, Isabel Feria‐Raposo, Irene Montoro, Beatriz Garcia‐Ruiz, Esther Jiménez, Cristina Varo, Àuria Albacete, Isabel Argila‐Plaza, Anna Lluch, Caterina del Mar Bonnín, Elisabet Vilella, Eduard Vieta, Edith Pomarol‐Clotet, Raymond Salvador
Abstract
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.