Alzheimer’s Imaging Consortium IC-P: Imaging Posters region, but with varying intensity and timing. The right parietal P7 effect is prominent in controls, but attenuated in AD and VaD. The P7 localizes to prefrontal cortex in controls, but involves only right posterior cortex in VaD, and central posterior cortex in AD. Conclusions: Source localization analysis shows that scalp ERP differences between AD and VaD can be unambiguously attributed to different underlying generators within the brain. We hypothesize that these effects reflect disease-specific neuropathology, and offer new functional biomarkers to aid in differential diagnosis of AD and VaD. IC-P-083
INVESTIGATION OF PERIVENTRICULAR WHITE MATTER HYPERINTENSITIES PRONE TO PROGRESSION FROM AMNESTIC MCI TO ALZHEIMER’S DISEASE
Rahyeong Juh1, JungSun Lee1, Seong Yoon Kim1,2, 1Dept. of Psychiatry, Asan Medical Center, Seoul, Korea, Republic of; 2Univ. of Ulsan, College of Medicine, Seoul, Korea, Republic of. Contact e-mail: rahyeong@catholic. ac.kr Background: White matter hyperintensities (WMH) have an effect on cognition and are increased in severity among individuals with amnestic mild cognitive impairment (MCI) and Alzheimer’s disease (AD). A quantitative method was applied to measure the volume of WMH with AD, MCI and the relationship between regional WMH and age and cognitive function was investigated. Our hypothesis was that WMH changes in the deep WM and periventricular WM detected by fluid-attenuated inversion recovery (FLAIR) should correlate with impaired performance on tests of executive function in AD and MCI. Methods: Forty AD (mean 73.4 6 6.7y) and 40 MCI (mean 70.9 6 7.4y) and 12 SMI subjects (mean age 74.3 6 7.4y) were included in this study. The FLAIR sequence is known to be optimal for WMH evaluation, we were used for unified analysis in this study. Data were drawn from a one or two years follow up MRI data from MCI to AD through periventricular WMH and deep WMH. Mini-Mental State Examination (MMSE) and cognitive scores in performing naming, language fluency, and memory tasks were obtained for correlation analysis. Results: AD patients had the greatest total WMH volume, followed by MCI, then SMI. However, there was a large variation within each group, and the difference did not reach a significant level. Conclusions: We demonstrated a quantitative analysis method to measure regional WMH. Although WMH was not strongly associated with disease severity or cognition, it may provide a characteristic neuroimaging parameter in the study of AD development. periventricular WMH are associated with an increased risk of progression from aMCI to AD. IC-P-084
HIPPOCAMPAL AND ENTORHINAL VOLUMETRY IN AMNESTIC MILD COGNITIVE IMPAIRMENT AND LATE-LIFE DEPRESSION
Jean-Franc¸ois Morin1, Carol Hudon2, Simon Duchesne3, 1Universite´ Laval, Quebec, QC, Canada; 2E´cole de psychologie, Universite´ Laval, Quebec, QC, Canada; 3Centre de Recherche Robert-Giffard Universite´ Laval (CRULRG), Quebec, QC, Canada. Contact e-mail: jean-francois.
[email protected] Background: Amnestic mild cognitive impairment (aMCI) and late-life depression (LLD) are two conditions associated with preclinical Alzheimer’s disease (AD). We wished to review if a) reported volumetric reductions, when compared to controls, were similar for the hippocampus (HC) and the entorhinal cortex (ERC) in both conditions; and b) if any study had assessed these structures in aMCI subjects with concomitant depression. Methods: We searched MEDLINE and found 57 articles describing MRI studies of HC and ERC in patients with aMCI or LLD; twenty-six met our inclusion criteria, 16 on aMCI and 10 on LLD. Results: We found that 1) total HC atrophy is reported as significant in all aMCI and LLD studies; 2) HC volume loss in LLD studies (5.5% to 13.8%) is reported similar to aMCI
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studies (7.1% to 19.0%); 3) total ERC atrophy is stated as significant in seven aMCI studies with volume losses ranging from 12.5% to 29.4%; 4) no LLD studies measured total or lateral ERC; 5) volume loss is reported more important in the ERC than for the HC in aMCI studies (e.g. 25.4% volume reduction for total ERC versus 15.9% for total HC in one study); and 6) no volumetric studies on aMCI subjects with concomitant depression were done. HC and ERC volumetric measurements vary considerably within and between aMCI and LLD groups (e.g. a factor of 2.3 when comparing lowest and highest total HC volume losses in aMCI). This may result from differences in terms of inclusion and exclusion criteria, demographic characteristics, but more importantly technical characteristics, especially segmentation protocols. Conclusions: HC volume loss in LLD studies is reported similar to the one observed in aMCI studies. No LLD studies measured the ERC. In aMCI studies, ERC volume loss appears more important that HC volume loss. The variability of measurements between aMCI and LLD studies raises the important issue of comparability. Future volumetric studies could benefit from using standardized segmentation protocols. No volumetric studies focusing on aMCI subjects with concomitant depression were found, and hence are needed in order to validate our interpretations.
IC-P-085
AMYLOID PET USING 18F-AV45 IN FRONTOTEMPORAL DEMENTIA
Emma R. L. C. Vardy, Rainer Hinz, Tobias Langheinrich, Julie Snowden, Alex Gerhard, Anna M. T. Richardson, Jose Anton, Gavin D. Brown, David Neary, Karl Herholz, University of Manchester, Manchester, United Kingdom. Contact e-mail:
[email protected] Background: 18F-AV-45 (Florbetapir F-18) is a novel positron emission tomography (PET) tracer for in vivo imaging of cerebral amyloid. We present preliminary results for differentiation between fronto-temporal dementia (FTD) and Alzheimer’s disease (AD) using 18F-AV-45. Methods: 18 F-AV-45 PET is to be performed in 15 subjects with AD, 15 subjects with FTD and 10 healthy controls (HC). All subjects undergo physical, biochemical and cognitive screening. Subjects are scanned for 60 min after injection on a high-resolution PET scanner and images are coregistered with 3D T1-weighted MRI. Late uptake images were analysed visually. For quantitative analysis, regions of interest were placed in frontal, temporal and parietal neocortical areas and tracer binding was analysed using cerebellar cortex as the reference region. Results: In subjects studied so far, cortical binding in FTD was comparable to normal controls and significantly lower than in AD. Non-specific binding to white matter was observed in all subjects. Conclusions: Results suggest that 18F-AV-45 has the potential to differentiate FTD from AD.
IC-P-086
VARIABILITY OF COGNITIVE CONDITIONS IN INDIVIDUALS SHOWING DIFFUSE OCCIPITAL HYPOMETABOLISM ON 18F-FDG PET SCANS
Hiroshige Fujishiro, Eizo Iseki, Norio Murayama, Koji Kasanuki, Kazumi Ota, Shinji Higashi, Ryoko Yamamoto, Masaru Suzuki, Heii Arai, Kiyoshi Sato, Juntendo University, Tokyo, Japan. Contact e-mail:
[email protected] Background: Diffuse areas of reduced cerebral metabolic rate of glucose (CMRglc) predominantly in the occipital lobe on18F-FDG PET scans is the preferentially affected region in patients with dementia with Lewy bodies (DLB). However, it is unknown when diffuse occipital hypometabolism on18F-FDG PET scans is found in patients with DLB during clinical course. Especially, the significance of particular patterns on 18F-FDG PET scans in prodromal patients with DLB remains unclear. Methods: We retrospectively reviewed findings on 18F-FDG PET scans in consecutive 134 individuals who underwent 18F-FDG PET scans through January of 2008 to November of 2009 in our memory clinic. In comparison with
