Metabolite 1H Transverse Relaxation Rates Measured in the Healthy Young Versus Elderly Human Brain at 4 T

Uzay E. Emir¹, Malgorzata Marjanska¹, Dinesh Deelchand¹, Melissa Terpstra¹

Differences in T₂ among experimental groups can confound quantification of metabolite concentrations. Existence of such differences in young versus elderly human subjects is controversial. This study used STEAM spectroscopy at several echo times to measure T₂ at ultra high magnetic field (4 T) in 29 young (age 18-22) and 32 elderly (age 70+) subjects. Artifact free spectra allowed for reliable determination of signal strengths via LCModel, which led to good fitting of the data to the T₂ relaxation curve for each metabolite. The T₂'s were faster in the elder than in the young subjects (p<0.01) for all metabolites.