Role of T1 mapping to evaluate brain aging in a healthy population.

PURPOSE: To investigate the relationship between healthy brain aging and T1 relaxation time obtained by T1 mapping. MATERIALS AND METHODS: A total of 211 (102 males, 109 females; age range: 20-89 years; mean age: 54 years) healthy volunteers underwent T1 mapping between July 2018 and January 2019. Regions of interest (ROIs) were placed on T1 maps in different anatomical regions, including the thalamus, putamen, globus pallidus, head of the caudate nucleus, nucleus accumbens, genu of the corpus callosum, and frontal lobe white matter (WM). Additionally, linear and quadratic regression analyses of ROIs were performed. RESULTS: There were significant quadratic and negative linear correlations between T1 relaxation times in the thalamus, putamen, and age (p < .001). Although the nucleus accumbens did not show a significant relationship between T1 relaxation times and age by linear regression (p = .624), a statistically significant relationship was obtained by quadratic regression (p < .001). For the globus pallidus, head of the caudate nucleus, genu of the corpus callosum and frontal lobe WM the quadratic regression analysis showed a better relationship than the linear correlation analysis. CONCLUSION: Age-related changes in T1 relaxation time vary by location in GM and WM.