Poster No:
1178
Submission Type:
Abstract Submission
Authors:
Zonghua Shi1, Jiatai Li2, Yuanzhe Huang3, Noah Schweitzer3, Bistra Iordanova3, Tamer Ibrahim3, Shaolin Yang3, George Stetten3, Howard Aizenstein3, Minjie Wu3
Institutions:
1Washington University in St. Louis, St. Louis, MO, 2Carnegie Mellon University, Pittsburgh, PA, 3University of Pittsburgh, Pittsburgh, PA
First Author:
Zonghua Shi
Washington University in St. Louis
St. Louis, MO
Co-Author(s):
Jiatai Li
Carnegie Mellon University
Pittsburgh, PA
Introduction:
Aging-related changes in cerebrovascular health include vessel structural alterations, reduced vessel elasticity, reduced blood flow, and impaired blood-brain barrier permeability, which may contribute to neurological and neurodegenerative diseases, such as Alzheimer's Disease (AD) (Zimmerman et al., 2021). In this study, we used 7T Time-of-flight (TOF) magnetic resonance angiography (MRA) to investigate age-related differences in arterial diameter and tortuosity in the brain in cognitively normal older adults.
Methods:
Our study comprised 25 older adults with normal cognition (20 females, average age of 68.3 ± 9.7 years). Whole-Brain TOF MRA images were acquired using a 7T Siemens scanner at the University of Pittsburgh, slice number=354, voxel size=0.38*0.38*0.38 mm³, 12 mins. Manual skull-stripping was performed to remove non-brain tissues on each TOF image, and the resulting brain mask was further dilated with 2-mm sphere to preserve vessels traveling along the surface of the brain. The cerebral arterial tree was segmented using VesselMapper, an automated vessel segmentation tool recently developed in our lab (Li et al., 2023). Arterial morphology was assessed using vessel diameter and vessel tortuosity. For each subject, vessels were
further categorized into three types based on vessel diameter, in which large vessels were defined as vessels with the top 33% diameter size, and small vessels as vessels with the bottom 33% diameter size. Pearson correlation analysis was performed to evaluate the association between age and vessel diameter and tortuosity.
Results:
As seen in Fig. 1, there is a significant positive association between age and large vessel diameter, so that older age is associated with a larger median diameter (r=0.42, p=0.03) (Fig. 1b). In contrast, there is a significant negative association between age and small vessel diameter, so that older age is associated with a smaller median diameter (r=-0.44, p=0.03) (Fig. 1c). As seen in Fig. 2, while large vessel tortuosity is not associated with age (r=0.06, p=0.78) (Fig. 2b), small vessels demonstrate an age-related decrease in median vessel tortuosity (r=-0.53, p=0.006) (Fig. 2c).

·Fig. 1: arterial tree colored by diameter (a), the association between age and vessel diameter of large vessels (b) and small vessels (c).

·Fig. 2: arterial tree colored by tortuosity (a), the association between age and vessel tortuosity of large vessels (b) and small vessels (c).
Conclusions:
The observed age-related increase in large vessel diameter (Fig. 1b) aligns with the gradual diameter increase with age in central and peripheral (lower and upper limb) vessels (Mandalà & Cipolla, 2021) (Thijssen et al., 2016). Vessel diameter dilation may reflect a compensatory enlargement (Polak et al., 1996), loss of elastic fibers (Fritze et al., 2012), reduced arterial storage capacity and compromised capability to attenuate pulse propagation with aging (Zeki Al Hazzouri & Yaffe, 2014). Age-related change in large vessels is accompanied by morphologic changes in small vessels (Fig. 1b and 1c), supporting a link between large vessel damage and distal small vessel alterations in the brain. Change in diameter in small vessels is also accompanied by change in tortuosity (Fig. 1c and Fig. 2c). The challenge with the small vessels is that their conspicuity is conflated by lower blood flow velocity. Age-related decrease in tortuosity may be a reflection of lower velocity in the small tortuous vessels.
Acknowledgement: This work was supported by the National Institute on Aging (R01AG067018 to Wu and RF1AG025516 to Aizenstein).
Lifespan Development:
Aging 1
Modeling and Analysis Methods:
Segmentation and Parcellation
Other Methods
Neuroanatomy, Physiology, Metabolism and Neurotransmission:
Neuroanatomy Other 2
Novel Imaging Acquisition Methods:
Imaging Methods Other
Keywords:
Aging
Cerebrovascular Disease
MR ANGIOGRAPHY
1|2Indicates the priority used for review
Provide references using author date format
Fritze, O., Romero, B., Schleicher, M., Jacob, M. P., Oh, D. Y., Starcher, B., Schenke-Layland, K., Bujan, J., & Stock, U. A. (2012). Age-related changes in the elastic tissue of the human aorta. Journal of vascular research, 49(1), 77–86. https://doi.org/10.1159/000331278
Li, J., Stetten, G., Schweitzer, N., Ibrahim, T. S., Iordanova B., Aizenstein, H., Wu, M. (2023). VesselMapper - A Robust Vessel Segmentation Algorithm for 3D Images. In Annual Meeting of the Organization for Human Brain Mapping.
Mandalà, M., & Cipolla, M. J. (2021). Aging-Related Structural and Functional Changes in Cerebral Arteries: Caloric Restriction (CR) Intervention. Journal of vascular medicine & surgery, 9(Suppl 7), 1000002.
Polak, J. F., Kronmal, R. A., Tell, G. S., O'Leary, D. H., Savage, P. J., Gardin, J. M., Rutan, G. H., & Borhani, N. O. (1996). Compensatory increase in common carotid artery diameter. Relation to blood pressure and artery intima-media thickness in older adults. Cardiovascular Health Study. Stroke, 27(11), 2012–2015. https://doi.org/10.1161/01.str.27.11.2012
Thijssen, D. H., Carter, S. E., & Green, D. J. (2016). Arterial structure and function in vascular ageing: are you as old as your arteries?. The Journal of physiology, 594(8), 2275–2284. https://doi.org/10.1113/JP270597
Zeki Al Hazzouri, A., & Yaffe, K. (2014). Arterial stiffness and cognitive function in the elderly. Journal of Alzheimer's disease : JAD, 42 Suppl 4(0 4), S503–S514. https://doi.org/10.3233/JAD-141563
Zimmerman, B., Rypma, B., Gratton, G., & Fabiani, M. (2021). Age-related changes in cerebrovascular health and their effects on neural function and cognition: A comprehensive review. Psychophysiology, 58(7), e13796. https://doi.org/10.1111/psyp.13796