Effects of Aging on Temporal Lobe Blood Flow with Structural Correction in Healthy Older Adults

Volume 12
Issue 2
Siyuan Hu, Hengyi Rao, Lauren Mancuso, Senhua Zhu, John A. Detre, & David A. Wolk
Aging has been associated with both cerebral blood flow (CBF) reductions and structural changes, particularly in the medial temporal lobe (MTL) region. However, it remains unclear whether the decline of CBF in the MTL is due entirely or just partially to anatomical changes. In the present study, pseudocontinuous arterial spin labeling (ASL) was used to measure quantitative CBF in forty-one healthy older adults. High-resolution T1-weighted structure images were also acquired from each subject. Robust age-related CBF decline and anatomical changes were observed in the medial and superior temporal lobe. After controlling for partial volume effect (PVE) and brain atrophy, there were still significant age-related regional CBF decreases in the right parahippocampus and the bilateral insula. However, regional CBF in the left parahippocampal gyrus was not correlated with age after PVE correction. Our results support the importance of structural correction for regional CBF quantification in aging populations and suggest that anatomical changes alone cannot explain the regional CBF decline in older adults.

Key words: cerebral blood flow, aging, partial volume ef fect, atrophy, parahippocampal gyrus, insula, superior temporal gyrus