- Email: [email protected]
Concordance and discordance between regional reduction of cerebral blood flow and brain atrophy in frontotemporal dementia
Alzheimer’s Imaging Consortium IC-P: Poster Presentations
P60
prefrontal, orbitofrontal, parietal, temporal, anterior cingulate and posterior cingulate/precuneus values divided by the cerebellar cortical PiB retention for each subject, with equal weighting of the individual values in computing the summary measure. Hippocampal volumes were analyzed as adjusted W-scores for head size, age and gender. Results: The global cortical PiB retention in DLB patients was on average lower than AD, but higher than cognitively normal subjects. Similarly, hippocampal Wscores of DLB patients were on average higher than AD, but lower than cognitively normal subjects. Three of the five (60%) DLB patients were ‘‘PiB positive’’ (global cortical PiB retention summary measure 1.5), and one subject was ‘‘borderline’’ (1.49). Hippocampal W-scores were lower than zero in three of the five (60%) DLB patients. Only one DLB patient had both hippocampal atrophy and ‘‘positive PiB.’’ Plotting hippocampal W-scores against global cortical PiB retention completely separated the DLB and AD subjects (Figure). Conclusions: MRI and PiB PET are complementary in distinguishing patients with DLB and AD, and provide insight into the pathological mechanisms underlying dementia in DLB patients. A majority of the DLB patients had PiB retention and/or hippocampal atrophy, in agreement with pathology studies showing that patients with clinically diagnosed DLB may often have some degree of additional AD pathology. IC-P-149
1
A TENSOR-BASED MORPHOMETRY STUDY OF PATIENTS WITH COGNITIVE IMPAIRMENT AND DEMENTIA IN PARKINSON’S DISEASE 1,2
1,2
1,2
Po H. Lu , Liana G. Apostolova , Amity E. Green , Kristy Hwang , Christine Chung3, Paul M. Thompson1,2, Alex Leow4, Grace Lee1, Carmen C. Janvin5, Jan P. Larsen6,7, Jeffrey L. Cummings1,4, Dag Aarsland5,7, Mona K. Beyer8,7, 1Department of Neurology, David Geffen School of Medicine, UCLA, Los Angeles, CA, USA; 2Laboratory of Neuro Imaging, David Geffen School of Medicine, UCLA, Los Angeles, CA, USA; 3Keck School of Medicine,University of Southern California, Los Angeles, CA, USA; 4Department of Psychiatry and Biobehavioral Sciences, David Geffen School of Medicine,UCLA, Los Angeles, CA, USA; 5Department of Geriatric Psychiatry, Stavanger University Hospital, Stavanger, Norway; 6Department of Neurology, Stavanger University Hosptal, Stavanger, Norway; 7The Norwegian Centre for Movement Disorders, Stavanger University Hospital, Stavanger, Norway; 8Department of Radiology, Stavanger University Hospital, Stavanger, Norway. Contact e-mail: plu@ mednet.ucla.edu Background: Cognitive impairment is exceedingly common among patients with Parkinson’s disease (PD), and a variety of cognitive domains are impaired early in PD. Both mild cognitive impairment (PDMCI) and dementia (PDD) are associated with PD. The brain changes accompanying cognitive decline in PD are still not fully established. Methods: We applied tensor based morphometry (TBM) to 3D T1-weighted MRI scans of 20 age-matched cognitively normal elderly (NC), 9 cognitively normal PD (PDND), 6 PDMCI, and 15 PDD subjects. We warped each individual image to the unbiased geometrical NC average template and created Jacobian maps showing the expansion or compression factor at each image point and statistical maps of between-group differences. Like voxel-based morphometry (VBM), TBM detects volumetric differences throughout the brain revealing 3D profiles of tissue excess or loss, creating statistical p maps. Results: Relative to NC, PDD subjects showed significant atrophy (p < 0.01) bilaterally in frontopolar and temporo-occipital areas; on the right in the posterior medial frontal, lateral medial temporal, lateral parieto-occipital and precuneal areas and on the left in the inferior and middle temporal areas. Relative to NC, PDMCI subjects showed significant atrophy (p < 0.01) in the left pregenual cingulate, right frontopolar, and precuneal, and bilaterally in the medial temporal areas. Relative to NC, in the PDND group only a few areas of significant tissue loss (p < 0.01) were found on the right side in the parahippocampal gyrus/medial temporal lobe, lateral medial temporal, medial frontal and postcentral areas. Conclusions: Cognitive decline in PD is associated with tissue loss. PDD subjects show detectable atrophy in more areas of the brain than PDMCI subjects.
Cognitive decline in PD seems to be associated with medial and lateral frontal, medial and inferior temporal, precuneal and parietal atrophy. The dementia profile of PDD is characterised by executive, visuospatial and attentional impairment. This corresponds well with the areas of tissue loss shown in this study. IC-P-150
CONCORDANCE AND DISCORDANCE BETWEEN REGIONAL REDUCTION OF CEREBRAL BLOOD FLOW AND BRAIN ATROPHY IN FRONTOTEMPORAL DEMENTIA
Soichiro Shimizu1,2, Yu Zhang1,2, Bruce L. Miller3, Joel H. Kramer3, Michael W. Weiner1,2, Norbert Schuff1,2, 1Center for Imaging of Neurodegenerative Diseases, Veterans Affairs Medical Center, San Francisco, CA, USA; 2Department of Radiology, University of California, San Francisco, San Francisco, CA, USA; 3Depertment of Neurology, University of California, San Francisco, San Francisco, CA, USA. Contact e-mail: soichiro. [email protected] Background: We previously showed that reduced cerebral blood flow (CBF) can be dissociated from gray matter atrophy and vice versa in Alzheimer’s disease (AD) that might potentially be useful for disease staging. The overall aim in this study was to determine if a similar dissociation between reduced CBF and gray matter atrophy also exists in frontotemporal dementia (FTD). Specifically, we hypothesized that in FTD dissociations between CBF and gray matter would occur predominantly in parietal brain regions, which are thought to be less vulnerable to FTD than frontal brain regions. In the frontal brain regions, we expected that CBF and gray matter atrophy would show concordant changes. Methods: The study included11 patients with FTD (mean age 56.9 6 9.9 yrs, mean MMSE 25.9 6 3.1) and 15 cognitive normal (CN) subjects (mean age 64.7 6 8.4, mean MMSE 29.7 6 0.60). All subjects had MRI at 1.5Tesla, including T1-weighted structural and arterial spin labeling (ASL) perfusion imaging. We performed a non-parametric concordance/discordance analysis to identify relationships between structural and perfusion MRI data. Results: Compared to controls, FTD patients had significant reductions of CBF in right lateral, bilateral medial frontal and left parietal lobes (p < 0.001). FTD also showed significant gray matter loss in bilateral frontal and temporal lobes (p < 0.001). A concordance/discordance analysis revealed that reduced CBF without gray matter atrophy occurred in left parietal lobe (p < 0.05) and gray matter atrophy without CBF reduction occurred in the right frontal lobe (p < 0.05). Concordant CBF reduction and gray matter loss was found in the frontal lobe (p < 0.05). Conclusions: The results demonstrate that FTD can be associated with regional dissociation between reduced CBF and brain atrophy, similar earlier findings in AD. However, the dissociations seem to be limited to parietal lobe regions while frontal lobe regions, which are primarily involved in FTD, show no significant dissociations. Whether this pattern of dissociation in FTD is different from that in AD needs to be determined.
P60
prefrontal, orbitofrontal, parietal, temporal, anterior cingulate and posterior cingulate/precuneus values divided by the cerebellar cortical PiB retention for each subject, with equal weighting of the individual values in computing the summary measure. Hippocampal volumes were analyzed as adjusted W-scores for head size, age and gender. Results: The global cortical PiB retention in DLB patients was on average lower than AD, but higher than cognitively normal subjects. Similarly, hippocampal Wscores of DLB patients were on average higher than AD, but lower than cognitively normal subjects. Three of the five (60%) DLB patients were ‘‘PiB positive’’ (global cortical PiB retention summary measure 1.5), and one subject was ‘‘borderline’’ (1.49). Hippocampal W-scores were lower than zero in three of the five (60%) DLB patients. Only one DLB patient had both hippocampal atrophy and ‘‘positive PiB.’’ Plotting hippocampal W-scores against global cortical PiB retention completely separated the DLB and AD subjects (Figure). Conclusions: MRI and PiB PET are complementary in distinguishing patients with DLB and AD, and provide insight into the pathological mechanisms underlying dementia in DLB patients. A majority of the DLB patients had PiB retention and/or hippocampal atrophy, in agreement with pathology studies showing that patients with clinically diagnosed DLB may often have some degree of additional AD pathology. IC-P-149
1
A TENSOR-BASED MORPHOMETRY STUDY OF PATIENTS WITH COGNITIVE IMPAIRMENT AND DEMENTIA IN PARKINSON’S DISEASE 1,2
1,2
1,2
Po H. Lu , Liana G. Apostolova , Amity E. Green , Kristy Hwang , Christine Chung3, Paul M. Thompson1,2, Alex Leow4, Grace Lee1, Carmen C. Janvin5, Jan P. Larsen6,7, Jeffrey L. Cummings1,4, Dag Aarsland5,7, Mona K. Beyer8,7, 1Department of Neurology, David Geffen School of Medicine, UCLA, Los Angeles, CA, USA; 2Laboratory of Neuro Imaging, David Geffen School of Medicine, UCLA, Los Angeles, CA, USA; 3Keck School of Medicine,University of Southern California, Los Angeles, CA, USA; 4Department of Psychiatry and Biobehavioral Sciences, David Geffen School of Medicine,UCLA, Los Angeles, CA, USA; 5Department of Geriatric Psychiatry, Stavanger University Hospital, Stavanger, Norway; 6Department of Neurology, Stavanger University Hosptal, Stavanger, Norway; 7The Norwegian Centre for Movement Disorders, Stavanger University Hospital, Stavanger, Norway; 8Department of Radiology, Stavanger University Hospital, Stavanger, Norway. Contact e-mail: plu@ mednet.ucla.edu Background: Cognitive impairment is exceedingly common among patients with Parkinson’s disease (PD), and a variety of cognitive domains are impaired early in PD. Both mild cognitive impairment (PDMCI) and dementia (PDD) are associated with PD. The brain changes accompanying cognitive decline in PD are still not fully established. Methods: We applied tensor based morphometry (TBM) to 3D T1-weighted MRI scans of 20 age-matched cognitively normal elderly (NC), 9 cognitively normal PD (PDND), 6 PDMCI, and 15 PDD subjects. We warped each individual image to the unbiased geometrical NC average template and created Jacobian maps showing the expansion or compression factor at each image point and statistical maps of between-group differences. Like voxel-based morphometry (VBM), TBM detects volumetric differences throughout the brain revealing 3D profiles of tissue excess or loss, creating statistical p maps. Results: Relative to NC, PDD subjects showed significant atrophy (p < 0.01) bilaterally in frontopolar and temporo-occipital areas; on the right in the posterior medial frontal, lateral medial temporal, lateral parieto-occipital and precuneal areas and on the left in the inferior and middle temporal areas. Relative to NC, PDMCI subjects showed significant atrophy (p < 0.01) in the left pregenual cingulate, right frontopolar, and precuneal, and bilaterally in the medial temporal areas. Relative to NC, in the PDND group only a few areas of significant tissue loss (p < 0.01) were found on the right side in the parahippocampal gyrus/medial temporal lobe, lateral medial temporal, medial frontal and postcentral areas. Conclusions: Cognitive decline in PD is associated with tissue loss. PDD subjects show detectable atrophy in more areas of the brain than PDMCI subjects.
Cognitive decline in PD seems to be associated with medial and lateral frontal, medial and inferior temporal, precuneal and parietal atrophy. The dementia profile of PDD is characterised by executive, visuospatial and attentional impairment. This corresponds well with the areas of tissue loss shown in this study. IC-P-150
CONCORDANCE AND DISCORDANCE BETWEEN REGIONAL REDUCTION OF CEREBRAL BLOOD FLOW AND BRAIN ATROPHY IN FRONTOTEMPORAL DEMENTIA
Soichiro Shimizu1,2, Yu Zhang1,2, Bruce L. Miller3, Joel H. Kramer3, Michael W. Weiner1,2, Norbert Schuff1,2, 1Center for Imaging of Neurodegenerative Diseases, Veterans Affairs Medical Center, San Francisco, CA, USA; 2Department of Radiology, University of California, San Francisco, San Francisco, CA, USA; 3Depertment of Neurology, University of California, San Francisco, San Francisco, CA, USA. Contact e-mail: soichiro. [email protected] Background: We previously showed that reduced cerebral blood flow (CBF) can be dissociated from gray matter atrophy and vice versa in Alzheimer’s disease (AD) that might potentially be useful for disease staging. The overall aim in this study was to determine if a similar dissociation between reduced CBF and gray matter atrophy also exists in frontotemporal dementia (FTD). Specifically, we hypothesized that in FTD dissociations between CBF and gray matter would occur predominantly in parietal brain regions, which are thought to be less vulnerable to FTD than frontal brain regions. In the frontal brain regions, we expected that CBF and gray matter atrophy would show concordant changes. Methods: The study included11 patients with FTD (mean age 56.9 6 9.9 yrs, mean MMSE 25.9 6 3.1) and 15 cognitive normal (CN) subjects (mean age 64.7 6 8.4, mean MMSE 29.7 6 0.60). All subjects had MRI at 1.5Tesla, including T1-weighted structural and arterial spin labeling (ASL) perfusion imaging. We performed a non-parametric concordance/discordance analysis to identify relationships between structural and perfusion MRI data. Results: Compared to controls, FTD patients had significant reductions of CBF in right lateral, bilateral medial frontal and left parietal lobes (p < 0.001). FTD also showed significant gray matter loss in bilateral frontal and temporal lobes (p < 0.001). A concordance/discordance analysis revealed that reduced CBF without gray matter atrophy occurred in left parietal lobe (p < 0.05) and gray matter atrophy without CBF reduction occurred in the right frontal lobe (p < 0.05). Concordant CBF reduction and gray matter loss was found in the frontal lobe (p < 0.05). Conclusions: The results demonstrate that FTD can be associated with regional dissociation between reduced CBF and brain atrophy, similar earlier findings in AD. However, the dissociations seem to be limited to parietal lobe regions while frontal lobe regions, which are primarily involved in FTD, show no significant dissociations. Whether this pattern of dissociation in FTD is different from that in AD needs to be determined.