Dataset Information

Voxelwise Relationships Between Distribution Volume Ratio and Cerebral Blood Flow: Implications for Analysis of ?-Amyloid Images.

ABSTRACT: UNLABELLED:Quantification of ?-amyloid (A?) in vivo is often accomplished using the distribution volume ratio (DVR), based on a simplified reference tissue model. We investigated the local relationships between DVR and cerebral blood flow (CBF), as well as relative CBF (R1), in nondemented older adults. METHODS:Fifty-five nondemented participants (mean age, 78.5 y) in the Baltimore Longitudinal Study of Aging underwent (15)O-H2O PET CBF and dynamic (11)C-PiB PET. (15)O-H2O PET images were normalized and smoothed using SPM. A simplified reference tissue model with linear regression and spatial constraints was used to generate parametric DVR images. The DVR images were regressed on CBF images on a voxel-by-voxel basis using robust biologic parametric mapping, adjusting for age and sex (false discovery rate, P = 0.05; spatial extent, 50 voxels). DVR images were also regressed on R1 images, a measure of the transport rate constant from vascular space to tissue. All analyses were performed on the entire sample, and on high and low tertiles of mean cortical DVR. RESULTS:Voxel-based analyses showed that increased DVR is associated with increased CBF in the frontal, parietal, temporal, and occipital cortices. However, this association appears to spare regions that typically show early A? deposition. A more robust relationship between DVR and CBF was observed in the lower tertile of DVR, that is, negligible cortical A? load, compared with the upper tertile of cortical DVR and A? load. The spatial distributions of the DVR-CBF and DVR-R1 correlations showed similar patterns. No reliable negative voxelwise relationships between DVR and CBF or R1 were observed. CONCLUSION:Robust associations between DVR and CBF at negligible A? levels, together with similar spatial distributions of DVR-CBF and DVR-R1 correlations, suggest that regional distribution of DVR reflects blood flow and tracer influx rather than pattern of A? deposition in those with minimal A? load. DVR-CBF associations in individuals with a higher DVR are more likely to reflect true associations between patterns of A? deposition and CBF or neural activity. These findings have important implications for analysis and interpretation of voxelwise correlations with external variables in individuals with varying amounts of A? load.

SUBMITTER: Sojkova J

PROVIDER: S-EPMC5367770 | biostudies-literature | 2015 Jul

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Voxelwise Relationships Between Distribution Volume Ratio and Cerebral Blood Flow: Implications for Analysis of β-Amyloid Images.

Sojkova Jitka J Goh Joshua J Bilgel Murat M Landman Bennett B Yang Xue X Zhou Yun Y An Yang Y Beason-Held Lori L LL Kraut Michael A MA Wong Dean F DF Resnick Susan M SM

Journal of nuclear medicine : official publication, Society of Nuclear Medicine 20150514 7

<h4>Unlabelled</h4>Quantification of β-amyloid (Aβ) in vivo is often accomplished using the distribution volume ratio (DVR), based on a simplified reference tissue model. We investigated the local relationships between DVR and cerebral blood flow (CBF), as well as relative CBF (R1), in nondemented older adults.<h4>Methods</h4>Fifty-five nondemented participants (mean age, 78.5 y) in the Baltimore Longitudinal Study of Aging underwent (15)O-H2O PET CBF and dynamic (11)C-PiB PET. (15)O-H2O PET ima ...[more]

PMID: 25977462

Similar Datasets

Project description:Background and Purpose- Magnetic resonance imaging visible perivascular spaces in the centrum semiovale (CSO-PVS) have been associated with cerebral amyloid angiopathy (CAA).We aimed to further confirm this link by evaluating CSO-PVS volume in pathologically-demonstrated sporadic and genetically-demonstrated hereditary forms of the disease. Methods- We studied a retrospective hospital-based cohort consisting of 63 individuals aged >55 having brain magnetic resonance imaging and pathological assessment of CAA (mean age, 73.6±8.5; 46% female), and a separate cohort consisting of 26 carriers, and 28 noncarriers of the hereditary cerebral hemorrhage with amyloidosis-Dutch type (mean age, 46.7±12.8; 61.1% female). CSO-PVS volume was quantified on a single magnetic resonance imaging slice using a computer-assisted segmentation method and expressed as the relative volume of the intracranial volume in that particular slice (CSO-PVS relative volume). We compared CSO-PVS relative volume (1) between subjects with and without the disease in both cohorts; (2) between non-CAA, CAA without hemorrhage, and CAA with hemorrhage cases in the sporadic CAA cohort. All variables reaching P<0.1 in bivariate analyses were entered in logistic regression models. Results- In both sporadic and Dutch cohorts, cases with CAA had significantly higher CSO-PVS relative volume than cases without (median [IQR]: 3.7% [2.5-5.3] versus 1.8% [1.2-2.4], P<0.0001; 3.8% [0.6-6.2] versus 0.7% [0.4-1.6], P=0.007; respectively). In linear regression models, sporadic CAA was associated with higher CSO-PVS relative volume ( P=0.008). In the sporadic CAA cohort, compared with non-CAA cases, CSO-PVS relative volume was higher in both CAA with hemorrhage and without hemorrhage (4.4% [2.6-6.1] and 3% [2.4-3.6] versus 1.8% [1.2-2.4], P<0.001 and P=0.005, respectively). Higher CSO-PVS relative volume was associated with CAA in regression models, both when hemorrhage was present (odds ratio, 2.63; [95% confidence interval, 1.33-5.18]; P=0.005) and absent (odds ratio, 4.55; [95% confidence interval, 0.98-21.04]; P=0.05). Conclusions- Increased CSO-PVS volume is a consistent magnetic resonance imaging marker of cerebrovascular amyloid deposition and a promising diagnostic tool for sporadic CAA without hemorrhagic manifestations.

Dataset Information

Voxelwise Relationships Between Distribution Volume Ratio and Cerebral Blood Flow: Implications for Analysis of ?-Amyloid Images.

Publications

Voxelwise Relationships Between Distribution Volume Ratio and Cerebral Blood Flow: Implications for Analysis of β-Amyloid Images.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets