Detection of age related differences in CBF with PCASL using 2 post label delays.

BACKGROUND The brain is reliant on an abundant and uninterrupted CBF for normal neural function because it is an organ with high metabolic activity and limited ability to store energy. PURPOSE This study aimed to compare age-related variations in CBF measured with PCASL. METHODS This prospective study included healthy volunteers at the Radiology Department of Shanxi Cardiovascular Hospital between October 2018 and July 2019. The volunteers were divided into three groups (n = 30 per group): young (≤44 years), middle-aged (45-59 years) and elderly (≥60 years). CBF was measured by PCASL using 2 post label delays (PLD) (PLD = 1.5 s, 2.5 s), and compared between PLDs and groups. The relation between CBF value and age was assessed by Pearson correlation analysis. RESULTS For PLD = 1.5 s, CBF differed significantly between groups for all brain regions (P < 0.05), with higher values in the young group and lower values in the elderly group. For PLD = 2.5 s, the young and middle-aged groups had broadly comparable CBF values, whereas the elderly group had higher CBF values (P < 0.05) for most brain regions. For both PLDs, no brain regions showed significant differences in CBF values between males and females. The CBF of all brain regions was negatively correlated with age for PLD = 1.5 s (P < 0.05) but not PLD = 2.5 s. Compared with PLD = 1.5 s, PLD = 2.5 s yielded lower CBF values for the young group and higher CBF values for the elderly group. CONCLUSION 3D-pCASL with dual PLDs can non-invasively evaluate age-related changes in CBF in healthy people.