An efficient approach to perform MR-assisted PET data optimization in simultaneous PET/MR neuroimaging studies
Journal
Journal of Nuclear Medicine
Journal Volume
60
Journal Issue
2
Pages
272-278
Date Issued
2019
Author(s)
Chen K.T.
Salcedo S.
Gong K.
Chonde D.B.
Izquierdo-Garcia D.
Drzezga A.
Rosen B.
Qi J.
Dickerson B.C.
Catana C.
Abstract
A main advantage of PET is that it provides quantitative measures of the radiotracer concentration, but its accuracy is confounded by factors including attenuation, subject motion, and limited spatial resolution. Using the information from one simultaneously acquired morphologic MR sequence with embedded navigators for MR motion correction (MC), we propose an efficient method, MR-assisted PET data optimization (MaPET), for attenuation correction (AC), PET MC, and anatomy-aided reconstruction. Methods: For AC, voxelwise linear attenuation coefficient maps were generated using an SPM8-based method on the MR volume. The embedded navigators were used to derive head motion estimates for event-based PET MC. The anatomy provided by the MR volume was incorporated into the PET image reconstruction using a kernel-based method. Region-based analyses were performed to assess the quality of images generated through various stages of PET data optimization. Results: The optimized PET images reconstructed with MaPET were superior in image quality to images reconstructed using only AC, with high signal-to-noise ratio and low coefficient of variation (5.08 and 0.229 in a composite cortical region compared with 3.12 and 0.570, P, 10? 4 for both comparisons). The optimized images were also shown using the Cohen’s d metric to achieve a greater effect size in distinguishing cortical regions with hypometabolism from regions of preserved metabolism. Conclusion: We have shown that the spatiotemporally correlated data acquired using a single MR sequence can be used for PET attenuation, motion, and partial-volume effects corrections and that the MaPET method may enable more accurate assessment of pathologic changes in dementia and other brain disorders. COPYRIGHT ? 2019 by the Society of Nuclear Medicine and Molecular Imaging.
Subjects
fluorodeoxyglucose f 18
accuracy
algorithm
Alzheimer disease
anatomy aided reconstruction
Article
attenuation correction
brain metabolism
clinical article
controlled study
female
frontotemporal dementia
human
image artifact
image quality
image reconstruction
information processing
kernel method
male
mild cognitive impairment
motion correction
neuroimaging
nuclear magnetic resonance imaging
positron emission tomography
priority journal
process optimization
signal noise ratio
SDGs
Type
journal article