- Email: [email protected]
Association of hippocampus head diffusivity and episodic memory performance in early Alzheimer's disease
P50
Alzheimer’s Imaging Consortium IC-P: Poster Presentations
between temporal and occipital lobes, had the lowest SD in BA22 and BA38; thus, they were finally considered as affected by Parkinsonism. Conclusions: Quantitative analysis used in the present study confirmed Brain SPECT diagnostic accuracy obtained by qualitative analysis in 55.5% of our cases while it gave more useful information in the remaining 44.5% of cases with unclear qualitative results. Moreover, only quantitative analysis suggested the correct diagnosis of Parkinsonism in false positive cases for LBD at both clinical examination and 123Ioflupane SPECT. IC-P-121
CORRELATION BETWEEN 18F-GE-067 AND 11C-PIB UPTAKE IN ALZHEIMER’S DISEASE AND MCI
Koen Van Laere1, Rik Vandenberghe1, Adrian Ivanoiu2, Eric Triau3, Ian Law4, Steen Hasselbalch4, Chris Buckley5, Lennart Thurfjell6, David J. Brooks5,7, 1UZ Gasthuisberg Leuven, Leuven, Belgium; 2University Hospital Saint Luc, Brussels, Belgium; 3Neurologie Centrum, Leuven, Belgium; 4Rigshospitalet, University of Copenhagen, Copenhagen, Denmark; 5 GE Healthcare, London, United Kingdom; 6GE Healthcare, Uppsala, Sweden; 7Imperial College, London, United Kingdom. Contact e-mail: koen. [email protected] Background: Clinical brain amyloid imaging would be facilitated by availability of an 18F-labeled compound without the need of an on-site cyclotron. In view of the knowledge built up around 11C-PIB, correlation studies between the 18F-labelled PIB derivative 18F-GE-067 and 11C-PIB are a means to provide further validity of the former novel compound. The aim of the study was to correlate within the same subjects 11C-PIB and 18F-GE-067 brain uptake in patients with clinically probable Alzheimer’s Disease (AD) and amnestic mild cognitive impairment (MCI) in a phase II clinical trial. Methods: Sequential studies were performed in 10 AD (MMSE 15-26, CDR 0.5-2) and 11 MCI (MMSE 27-30, CDR 0-0.5). Following injection of 327 6 33 MBq of 11C-PIB, PET scanning was performed 40-70 min post injection (p.i.). Usually the same day (interval 1 6 5 days), 170 6 21 MBq of 18F-GE-067 was injected and subjects were scanned 85-115 min p.i.11C-PIB and 18F-GE-067 images were co-registered with the subject’s MRI and all scans were spatially normalised. A volume of interest template was applied and target region to cerebellar grey matter uptake ratios (SUVR) were derived. Results: Comparison of 18F-GE-067 and 11C-PIB SUVR values across brain regions showed that SUVR values for cortical regions were very similar, with a tendency for slightly lower SUVR for 18F-GE067. Subcortical white matter (SWM) and the pons, showed higher SUVR in 18F-GE067. One subject showed a different pattern with approximately 40% higher SUVR in 18F-GE-067 and was excluded from the correlation analysis. For cortical regions Pearson’s R2 was between 93.6% (anterior cingulum) and 95.2% (temporal lateral cortex). R2 for a composite region, com-
puted as a volume weighted average of frontal, parietal and temporal lateral corticies and anterior and posterior cinguli, was 95.0%. The regression line for this region was ‘‘ [18F-GE-067] ¼ 0.22 þ 0.86 [11C-PIB]’’. For aspecific uptake regions, the corresponding values were: Pons R2 ¼ 75%, intercept ¼ 0 and slope ¼ 1.27 and SWM R2 ¼ 69%, intercept ¼ 0 and slope ¼ 1.34, respectively. Conclusions: Specific tracer binding of 18F-GE-067 is very similar to 11C-PIB for cortical regions, while SUVR in pons and SWM is approximately 30% higher than in 11C-PIB. Linear regression of 18F-GE-067 against 11C-PIB. The identity line is shown as a dotted line. IC-P-122
ASSOCIATION OF HIPPOCAMPUS HEAD DIFFUSIVITY AND EPISODIC MEMORY PERFORMANCE IN EARLY ALZHEIMER’S DISEASE
Andreas Fellgiebel, Igor Yakushev, Ingrid Schermuly, Markus Lorscheider, Isabel Keller, Juliane Albrecht, Peter Stoeter, University of Mainz, Mainz, Germany. Contact e-mail: [email protected] Background: Hippocampal atrophy is a major structural imaging finding in early Alzheimer’s disease (AD). Corresponding to the neuropathological finding of early neurofibrillary tangle accumulation within the CA1 subfield recent studies showed pronounced volume loss within the lateral hippocampal regions in mild cognitive impairment and mild AD. There is also increasing evidence that the anterior hippocampus plays a crucial role in the formation of memories. Methods: To investigate whether structural disturbances of the anterior part of the hippocampus are associated with impaired episodic memory function we correlated several global and regional hippocampal diffusivity and hippocampal volume measurements in 12 patients with early AD (MMSE 25.3 6 1.8) with the cognitive performance of the patients. Results: Compared to a group of 16 age- and education-matched normal controls all global and regional hippocampal volumes were significantly decreased bilaterally in early AD with a pronounced volume difference within the anterior hippocampus (hippocampus head). Early AD patients showed significant diffusivity increases only within the hippocampus head bilaterally. Episodic memory performance (delayed verbal recall test) correlated most strongly with increased left hippocampal head diffusivity of the patients group (r ¼ - 0.72, p ¼ 0.008). Significant correlations of the verbal delayed recall test with decreased hippocampal volume in the bodytail regions bilaterally (left: r ¼ 0.59, p ¼ 0.045; right: r ¼ 0.58, p ¼ 0.048) could also be found in the patient group. Conclusions: Our findings suggest that elevated diffusivity is a sensitive and early marker of functional relevant structural disturbances of the hippocampus in AD. Moreover, increases of cross-sectional left anterior hippocampal diffusivity seem to be more closely related to verbal memory impairment than global or regional hippocampal volume reductions. Additionally, these data support the assumption that the anterior hippocampus contains necessary neuronal substrates of episodic memory function. IC-P-123
A DIRECT COMPARISON OF VENTRICULAR VOLUMES DERIVED FROM 1.5 TESLA AND 3.0 TESLA MRI IN 115 ADNI PARTICIPANTS
Sean M. Nestor1, Michael Borrie2,3, Matthew Smith3, Robert Bartha1, 1 Robarts Research Institute, University of Western Ontario, London, ON, Canada; 2Department of Medicine, University of Western Ontario, London, ON, Canada; 3Lawson Health Research Institute, St. Joseph’s Health Care, London, ON, Canada. Contact e-mail: [email protected] Background: Ventricular enlargement measured from T1-weighted magnetic resonance images (MRI) is an indirect measure of Alzheimer disease (AD) progression. Most MRI volumetric studies have assessed structural change derived from 1.5 Tesla MRI. However, 3.0 Tesla scanners are becoming prevalent, and there are few studies assessing potential differences in volumetry between field strengths. More than 25% of ADNI subjects undergo both 1.5 Tesla and 3.0 Tesla MRI. Objectives: to compare the sensitivity of ventricular measures derived from both 1.5 Tesla and 3.0 Tesla MRI in the same subjects. Methods: Baseline and 12-month data were obtained from the Alzheimer Disease Neuroimaging Initiative (ADNI), including 42
Alzheimer’s Imaging Consortium IC-P: Poster Presentations
between temporal and occipital lobes, had the lowest SD in BA22 and BA38; thus, they were finally considered as affected by Parkinsonism. Conclusions: Quantitative analysis used in the present study confirmed Brain SPECT diagnostic accuracy obtained by qualitative analysis in 55.5% of our cases while it gave more useful information in the remaining 44.5% of cases with unclear qualitative results. Moreover, only quantitative analysis suggested the correct diagnosis of Parkinsonism in false positive cases for LBD at both clinical examination and 123Ioflupane SPECT. IC-P-121
CORRELATION BETWEEN 18F-GE-067 AND 11C-PIB UPTAKE IN ALZHEIMER’S DISEASE AND MCI
Koen Van Laere1, Rik Vandenberghe1, Adrian Ivanoiu2, Eric Triau3, Ian Law4, Steen Hasselbalch4, Chris Buckley5, Lennart Thurfjell6, David J. Brooks5,7, 1UZ Gasthuisberg Leuven, Leuven, Belgium; 2University Hospital Saint Luc, Brussels, Belgium; 3Neurologie Centrum, Leuven, Belgium; 4Rigshospitalet, University of Copenhagen, Copenhagen, Denmark; 5 GE Healthcare, London, United Kingdom; 6GE Healthcare, Uppsala, Sweden; 7Imperial College, London, United Kingdom. Contact e-mail: koen. [email protected] Background: Clinical brain amyloid imaging would be facilitated by availability of an 18F-labeled compound without the need of an on-site cyclotron. In view of the knowledge built up around 11C-PIB, correlation studies between the 18F-labelled PIB derivative 18F-GE-067 and 11C-PIB are a means to provide further validity of the former novel compound. The aim of the study was to correlate within the same subjects 11C-PIB and 18F-GE-067 brain uptake in patients with clinically probable Alzheimer’s Disease (AD) and amnestic mild cognitive impairment (MCI) in a phase II clinical trial. Methods: Sequential studies were performed in 10 AD (MMSE 15-26, CDR 0.5-2) and 11 MCI (MMSE 27-30, CDR 0-0.5). Following injection of 327 6 33 MBq of 11C-PIB, PET scanning was performed 40-70 min post injection (p.i.). Usually the same day (interval 1 6 5 days), 170 6 21 MBq of 18F-GE-067 was injected and subjects were scanned 85-115 min p.i.11C-PIB and 18F-GE-067 images were co-registered with the subject’s MRI and all scans were spatially normalised. A volume of interest template was applied and target region to cerebellar grey matter uptake ratios (SUVR) were derived. Results: Comparison of 18F-GE-067 and 11C-PIB SUVR values across brain regions showed that SUVR values for cortical regions were very similar, with a tendency for slightly lower SUVR for 18F-GE067. Subcortical white matter (SWM) and the pons, showed higher SUVR in 18F-GE067. One subject showed a different pattern with approximately 40% higher SUVR in 18F-GE-067 and was excluded from the correlation analysis. For cortical regions Pearson’s R2 was between 93.6% (anterior cingulum) and 95.2% (temporal lateral cortex). R2 for a composite region, com-
puted as a volume weighted average of frontal, parietal and temporal lateral corticies and anterior and posterior cinguli, was 95.0%. The regression line for this region was ‘‘ [18F-GE-067] ¼ 0.22 þ 0.86 [11C-PIB]’’. For aspecific uptake regions, the corresponding values were: Pons R2 ¼ 75%, intercept ¼ 0 and slope ¼ 1.27 and SWM R2 ¼ 69%, intercept ¼ 0 and slope ¼ 1.34, respectively. Conclusions: Specific tracer binding of 18F-GE-067 is very similar to 11C-PIB for cortical regions, while SUVR in pons and SWM is approximately 30% higher than in 11C-PIB. Linear regression of 18F-GE-067 against 11C-PIB. The identity line is shown as a dotted line. IC-P-122
ASSOCIATION OF HIPPOCAMPUS HEAD DIFFUSIVITY AND EPISODIC MEMORY PERFORMANCE IN EARLY ALZHEIMER’S DISEASE
Andreas Fellgiebel, Igor Yakushev, Ingrid Schermuly, Markus Lorscheider, Isabel Keller, Juliane Albrecht, Peter Stoeter, University of Mainz, Mainz, Germany. Contact e-mail: [email protected] Background: Hippocampal atrophy is a major structural imaging finding in early Alzheimer’s disease (AD). Corresponding to the neuropathological finding of early neurofibrillary tangle accumulation within the CA1 subfield recent studies showed pronounced volume loss within the lateral hippocampal regions in mild cognitive impairment and mild AD. There is also increasing evidence that the anterior hippocampus plays a crucial role in the formation of memories. Methods: To investigate whether structural disturbances of the anterior part of the hippocampus are associated with impaired episodic memory function we correlated several global and regional hippocampal diffusivity and hippocampal volume measurements in 12 patients with early AD (MMSE 25.3 6 1.8) with the cognitive performance of the patients. Results: Compared to a group of 16 age- and education-matched normal controls all global and regional hippocampal volumes were significantly decreased bilaterally in early AD with a pronounced volume difference within the anterior hippocampus (hippocampus head). Early AD patients showed significant diffusivity increases only within the hippocampus head bilaterally. Episodic memory performance (delayed verbal recall test) correlated most strongly with increased left hippocampal head diffusivity of the patients group (r ¼ - 0.72, p ¼ 0.008). Significant correlations of the verbal delayed recall test with decreased hippocampal volume in the bodytail regions bilaterally (left: r ¼ 0.59, p ¼ 0.045; right: r ¼ 0.58, p ¼ 0.048) could also be found in the patient group. Conclusions: Our findings suggest that elevated diffusivity is a sensitive and early marker of functional relevant structural disturbances of the hippocampus in AD. Moreover, increases of cross-sectional left anterior hippocampal diffusivity seem to be more closely related to verbal memory impairment than global or regional hippocampal volume reductions. Additionally, these data support the assumption that the anterior hippocampus contains necessary neuronal substrates of episodic memory function. IC-P-123
A DIRECT COMPARISON OF VENTRICULAR VOLUMES DERIVED FROM 1.5 TESLA AND 3.0 TESLA MRI IN 115 ADNI PARTICIPANTS
Sean M. Nestor1, Michael Borrie2,3, Matthew Smith3, Robert Bartha1, 1 Robarts Research Institute, University of Western Ontario, London, ON, Canada; 2Department of Medicine, University of Western Ontario, London, ON, Canada; 3Lawson Health Research Institute, St. Joseph’s Health Care, London, ON, Canada. Contact e-mail: [email protected] Background: Ventricular enlargement measured from T1-weighted magnetic resonance images (MRI) is an indirect measure of Alzheimer disease (AD) progression. Most MRI volumetric studies have assessed structural change derived from 1.5 Tesla MRI. However, 3.0 Tesla scanners are becoming prevalent, and there are few studies assessing potential differences in volumetry between field strengths. More than 25% of ADNI subjects undergo both 1.5 Tesla and 3.0 Tesla MRI. Objectives: to compare the sensitivity of ventricular measures derived from both 1.5 Tesla and 3.0 Tesla MRI in the same subjects. Methods: Baseline and 12-month data were obtained from the Alzheimer Disease Neuroimaging Initiative (ADNI), including 42