P870
P4-373
Poster Presentations: P4
DIFFUSION TENSOR IMAGING (DTI) OF WHITE MATTER INTEGRITY, BUT NOT STRUCTURAL OR PERFUSION MRI, IDENTIFIES CHANGES IN PRECLINICAL ALZHEIMER’S DISEASE
Linda Chao1, Seghel Yohannes2, Diana Truran2, Joel H. Kramer3, Carina Mari Aparici4, Michael Weiner5, 1UCSF, San Francisco, California, United States; 2Center for Imaging of Neurodegenerative Diseases, San Francisco, California, United States; 3Memory Clinic, UCSF, San Francisco, California, United States; 4University of California, San Francisco, San Francisco, California, United States; 5Center for Imaging of Neurodegenerative Diseases; VA Medical Center and UCSF, San Francisco, California, United States. Contact e-mail:
[email protected]
Background: When amyloid beta (Ab) is detected in the brains of normal elders, they are considered to have preclinical Alzheimer’s disease (AD). The goal of this study was to investigate whether gray or white matter changes can be detected with multimodality imaging in cognitively normal individuals with preclinical AD. Methods: Thirty cognitively normal adults (mean age: 7267 year old, mean MMSE: 29.660.7; CDR: 0) were studied with 18 F-labeled Florbetapir PET, structural, arterial spin labeled (ASL), and diffusion tensor imaging (DTI), and neuropsychological assessment. Subjects were dichotomized as amyloid positive (n¼13) and negative (n¼17) based on visual assessment of their florbetapir scans. Measures of volume, cerebral perfusion, and white matter integrity, quantified with fractional anisotropy (FA) by DTI, were extracted from AD-vulnerable regions of interest (ROIs, i.e., hippocampus, precuneus, posterior cingulate, fornix,
Subject demographics, behavioral, and imaging measures Amyloid - (n¼17) Mean/No. Age (years) Education (years) No. Men No. APOE ε4 carrier CDR MMSE GDS Global SUVr Precuneus SUVr Behavioral measuresa CVLT Learning trials 1-5 Long delay free recall WMS Visual Reproduction Immediate Delayed D-KEFS Trails Switching (time) D-KEFS Color-Word Interference Interference (time) Switching (time) Imaging measures Volume (in cc)b Hippocampus Precuneus Posterior Cingulate ASL Perfusion (arbitrary units) Hippocampus Precuneus Posterior Cingualte Fractional Anisotropy Fornix Parahippocampal WM Cingulum 1 Cingulum 2 Cingulum 3 Cingulum 4 CC- genu CC-body CC-splenium
Amyloid + (n¼13) SD /%
Mean /No.
SD /%
p-value
Cohen’s d
70.2 17.3 7 7 0.0 29.8 4.3 1.03 1.07
5.7 1.7 41% 41% 0.0 0.4 7.5 0.04 0.14
73.3 17.9 6 6 0.0 29.5 1.8 1.24 1.39
8.4 1.7 46% 46% 0.0 0.9 1.4 0.13 0.19
0.23 0.38 0.79 0.35 0.27 0.24
