Normal Aging Brain
Click on to view the abstract pdf and click on to view the video presentation.
 
Friday May 13th
Room 710A  10:30 - 12:30 Moderators: Christopher Hess and Patrik Zamecnik

10:30 774.   Age Effects on the Amplitude and Frequency of Resting-State BOLD Fluctuations  -permission withheld
J. Jean Chen1,2, Tyler D Triggs1, H. Diana Rosas1,3, and David H Salat1,2
1Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, United States, 2Department of Radiology, Massachusetts General Hospital, Boston, MA, United States, 3Department of Neurology, Massachusetts General Hospital, Boston, MA, United States

 
Spontaneous BOLD fluctuations in the resting-state have been used extensively to investigate neural connectivity, predominantly by examining the correlation between the time courses in multiple brain regions, which can be influenced by the amplitude of BOLD response. Both the amplitude and frequency traits of BOLD have been associated with vascular tone, which can be related to cerebral blood flow (CBF). In this work, we found higher BOLD fluctuation amplitudes to be associated with lower CBF and lower fluctuation frequency. These BOLD time-course parameters are potential indicators of vascular elasticity and hence of cerebrovascular changes in aging and disease.

 
10:42 775.   Association between Cerebral Blood Flow and Age-Related Changes in White Matter Microstructure  -permission withheld
J. Jean Chen1,2, H. Diana Rosas1,3, and David H Salat1,2
1Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, United States, 2Department of Radiology, Massachusetts General Hospital, Boston, MA, United States, 3Department of Neurology, Massachusetts General Hospital, Boston, MA, United States

 
White matter (WM) degeneration occurs in normal aging and age-related diseases, and was found to be strongly influenced by cerebrovascular health. However, it remains unclear how WM deterioration is associated with cerebral blood flow (CBF), a metric of vascular and metabolic health which has been associated with aging. In this work, we found CBF to be significantly associated with diffusion-tensor imaging-derived measures of WM integrity, demonstrating a definitive link between neurovascular factors and WM deterioration even within each age group. We also found a spatial correspondence between the effects of cortical perfusion and aging on underlying WM structural changes.

 
10:54 776.   Aging Effect on Human Brain Transverse Relaxation since Preadolescence 
Jianli Wang1, Megha Patel1, Deborah Dossick1, Michele L Shaffer2, Christopher W Weitekamp1, Xiaoyu Sun1, Jeffrey Vesek1, Paul J Eslinger3, David J Jill3, James R Connor4, and Qing X Yang1,4
1Radiology, Penn State College of Medicine, Hershey, PA, United States, 2Public Health Sciences, Penn State College of Medicine, Hershey, PA, United States, 3Neurology, Penn State College of Medicine, Hershey, PA, United States, 4Neurosurgery, Penn State College of Medicine, Hershey, PA, United States

 
The goal of this study was to elucidate a quantitative developmental/aging characteristics and its variability on regional transverse relaxation rates (R2) in normal human brain without a priori models. R2 maps were acquired from seventy-seven 9 to 85 year-old healthy volunteers at 3 T. The result shows that the age dependence of R2varied with respect to brain anatomy. The relationships between R2 and age determined by generalized additive models were nonlinear in most of the 25 brain structures studied.

 
11:06 777.   Genetic Influences on White Matter Microstructure in 280 Twins Scanned with 4 Tesla High Angular Resolution Diffusion Imaging (HARDI) 
Agatha D Lee1, Natasha Lepore2, Caroline C Brun3, Marina Barysheva4, Arthur Toga4, Katie L McMaho5, Greig I de Zubicaray6, Nicholas G Martin6, Margaret Wright6, and Paul M Thompson4
1Neurology, LONI-UCLA, Los Angeles, CA, United States, 2CHLA -USC, 3UPENN, 4LONI-UCLA, 5Centre for Magnetic Resonance, University of Queensland, 6Queensland Institute of Medical Research

 
Genetic Influences on White Matter Microstructure in 280 Twins Scanned with 4 Tesla High Angular Resolution Diffusion Imaging

 
11:18 778.   Preliminary Evidence of Increased Brain Acetate Uptake and Oxidation in Heavy Drinkers Probed by 13C-MRS 
Lihong Jiang1, Barbara Gulanski2, Stuart Weinzimer3, Ismene Petrakis3, Elizabeth Guidone3, Julia Koretski3, and Graeme Mason4
1Diagnostic Radiology, Yale University School of Medicine, New Haven, CT, United States, 2Internal Medicine, Yale University School of Medicine, 3Psychiatry, Yale University School of Medicine, 4Diagnostic Radiology, Yale University School of Medicine

 
Alcohol enters the metabolic pathway by converting first to aldehyde and then to acetate through respective enzymes. Drinking alcohol leads to elevated blood acetate levels. The objective of this study is to test whether heavy alcohol use can affect brain choice of energy sources, thereby providing insight to alcohol addiction and abuse. Using 2-13C-acetate as metabolic tracer, combining with in vivo localized 13C-magnetic resonance spectroscopy, we have found that heavy drinkers have elevated resting state plasma acetate concentration, as well as transport and metabolism of acetate in brain. Our results suggest that systematic available acetate may provide reward for drinking.

 
11:30 779.   Age and gender related alterations in brain perfusion dynamics 
Yinan Liu1,2, Xiaoping Zhu1, David Feinberg2,3, Matthias Guenther4,5, Howard Rosen6, Michael W Weiner1,2, and Norbert Schuff1,2
1Center for Imaging of Neurodegenerative Diseases, Department of Veterans Affairs Medical Center, San Francisco, CA, United States, 2Department of Radiology and Biomedical Imaging, University of California, San Francisco, CA, United States, 3Advanced MRI Technology LLC, Sebastopol, CA, United States, 4Mediri GmbH, Heidelberg, Germany, 5Department of Neurology, Klinikum Mannheim, University Heidelberg, Mannheim, Germany, 6Department of Neurology, University of California, San Francisco, CA, United States

 
While CBF reductions with advancing age have been interpreted as a consequence of reduced brain activity, there is also compelling evidence for compromised cerebrovascular integrity contributing to CBF reductions. In this study, we used ASL MRI to determine the brain perfusion as a function of aging and gender. Besides conformational findings of CBF reductions with advancing age and variations by gender, we also found prolonged arterial-arterioles transit time. The findings imply that vascular factors and gender effects cannot be neglected when evaluating age-related perfusion variations.

 
11:42 780.   Regional Changes of Cortical Mean Diffusivity with Ageing and Alzheimer Disease after Correction of Partial Volume Effects 
Tina Jeon1, Virendra Mishra1, Myron Weiner2, Kristin Martin-Cook3, Kimmo Hatanpaa4, Chan Foong4, and Hao Huang1
1Advanced Imaging Research Center, University of Texas Southwestern Medical Center, Dallas, TX, United States, 2Department of Psychiatry, University of Texas Southwestern Medical Center, Dallas, TX, United States, 3Department of Neurology, University of Texas Southwestern Medical Center, Dallas, TX, United States,4Department of Pathology, University of Texas Southwestern Medical Center, Dallas, TX, United States

 
Conventional VBM (voxel-based-morphometry) approaches delineate the abnormality at the voxel level. However, it is the information reflected from whole white matter tracts that have clinical importance. In this study, with no a priori information, this novel atlas-based approach has been used to examine fractional anisotropy (FA) of DTI of all 50 major white matter tracts at the tract level to detect white matter disruption in Alzheimer disease (AD). The proposed method is highly efficient, accurate, makes comprehensive examination of all major tracts and allows comparison of disruption level of these tracts.

 
11:54 781.   Effect of Aging on CBF mapping of Default Mode Network : An fMRI study 
Ying Hao1, Jing Liu2, Yue Zhang3, Xiaoying Wang1,4, Jue Zhang1,3, and Jing Fang1,3
1Academy for Advanced Interdisciplinary Studies, Peking University, Beijing, Beijing, China, People's Republic of, 2Dept. of Radiology, Peking University First Hospital, Beijing, Beijing, China, People's Republic of, 3College of Engineering, Peking University, Beijing, Beijing, China, People's Republic of, 4Dept. of Radiology, Peking University First Hospital, Beijing, Beijing, Beijing, China, People's Republic of

 
This study first depicted the effect of aging on the CBF-based correlations in DMN system. Compared with adult group, the correlation of the aging group with PCC node was found significantly decreased in the areas including right vMPFC and STG, which is in accordance with the previous BOLD-based studies. In addition, this study may shed light on the potential application of CBF signals in depicting functional connectivity mapping.

 
12:06 782.   Multi modal MRI reveals early life brain changes in human ApoE-lower case Greek epsilon4 carriers 
Ory Levy1, Anat Bar-Shira2, Avi Orr-Urtreger2,3, and Yaniv Assaf1
1Department of Neurobiology, Life Sciences Faculty, Tel aviv University, Tel Aviv, Israel, 2The Genetic Institute, Tel-Aviv Sourasky Medical Center, Tel-Aviv, Israel, 3The Sackler Faculty of Medicine, Tel aviv University, Tel Aviv, Israel

 
Carriers of APOE-4 allele have a 2-3 fold risk of developing Alzheimer's. difference in APOE4 brain structure are known for 50 years old, and for glucose metabolism in 20 years old normal subjects. Here, 52 healthy Ashkenazi Jews (ages 20-35), were genotyped and underwent MRI protocol including DTI, T1 and T2. ANOVA statistics revealed that T1 VBM and DTI and T2maps VBA indicate significant differences between APOE33\23 (29,8) and APOE34 (11) in the parahippocampal gyrus, the hippocampus and the globus pallidus, the orbitofrontal cortex, and the dorsolateral prefrontal cortex. Our findings implicate that APOE affects the brain since developmental stages.

 
12:18 783.   Paradoxically reduced cerebral vascular reactivity in Masters Athletes 
Binu P Thomas1,2, Uma Sreekumar Yezhuvath1, Rong Zhang3,4, Benjamin Yichen Tseng3,4, Benjamin Levine3,4, and Hanzhang Lu1,2
1Advanced Imaging Research Center, University of Texas Southwestern Medical Center, Dallas, TX, United States, 2Biomedical Engineering, University of Texas Southwestern Medical Center/University of Texas at Arlington, TX, United States, 3Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital, Dallas, TX, United States, 4Internal Medicine-Cardiology, University of Texas Southwestern Medical Center, Dallas, TX, United States

 
This study examines benefits of long term physical exercise on brain vasculature. 10 Masters Athletes (MA) (age=755.8) and 10 sedentary elders (age=755.6) were recruited. Cerebral vascular reactivity (CVR) and baseline cerebral blood flow were measured on a 3T. CVR is the ability of vasculature to respond to CO2 which indicates vascular elasticity. MA paradoxically show lower CVR compared to SED in frontal, temporal, parietal, occipital lobes and cerebellum. Baseline CBF is increased in MA in posterior cingulate/precuneus which is a node in the default mode network indicating a protection from age related reduction in vascular function in these regions.