Purpose: To report a systematic investigation of variations in brain T1ρ (T1-rho) values over adulthood, and present normative values for cortical gray matter, juxtacortical white matter, selected white matter tracts and subcortical structures.
Materials and methods: Forty-one healthy control subjects (23 males aged 18-76 years and 18 females aged 21-73 years) were imaged at 3.0 Tesla (T) using a novel whole-brain T1ρ-weighted fluid suppressed three-dimensional turbo spin echo technique. T1ρ maps were calculated and atlas-based segmentation used to determine regional T1ρ values. Linear regression was used to determine changes in T1ρ with age.
Results: T1ρ values showed significant decreases with age in cortical gray matter (P < 0.001), left and right caudate (P = 0.004/0.006), putamen (P = 0.001, P < 0.001), hippocampus (P = 0.039/0.010), amygdala (P = 0.002/0.001), and nucleus accumbens (P = 0.001/0.002). Significant increases with age (P < 0.05) were observed in all the white matter tracts considered, except the corticospinal tracts and forceps major.
Conclusion: T1ρ demonstrates changes related to the processes of normal aging.
Keywords: MRI; T1-rho (T1rho, T1ρ); aging; brain; spin-lock.
© 2013 Wiley Periodicals, Inc.