title: Comparison of MR-less PiB SUVR quantification methods.
abstract: (11)C-Pittsburgh compound B (PiB) is a positron emission tomography (PET) tracer designed to bind to amyloid-β (Aβ) plaques, one of the hallmarks of Alzheimer's disease (AD). The potential of PiB as an early marker of AD led to the increasing use of PiB in clinical research studies and development of several F-18-labeled Aβ radiotracers. Automatic quantification of PiB images requires an accurate parcellation of the brain's gray matter (GM). Typically, this relies on a coregistered magnetic resonance imaging (MRI) to extract the cerebellar GM, compute the standardized uptake value ratio (SUVR), and provide parcellation and segmentation for quantification of regional and global SUVR. However, not all subjects can undergo MRI, in which case, an MR-less method is desirable. In this study, we assess 3 PET-only quantification methods: a mean atlas, an adaptive atlas, and a multi-atlas approaches on a database of 237 subjects having been imaged with both PiB PET and MRI. The PET-only methods were compared against MR-based SUVR quantification and evaluated in terms of correlation, average error, and performance in classifying subjects with low and high Aβ deposition. The mean atlas method suffered from a significant bias between the estimated neocortical SUVR and the PiB status, resulting in an overall error of 5.6% (R(2) = 0.98), compared with the adaptive and multi-atlas approaches that had errors of 3.06% and 2.74%, respectively (R(2) = 0.98), and no significant bias. In classifying PiB-negative from PiB-positive subjects, the mean atlas had 10 misclassified subjects compared with 0 for the adaptive and 1 for the multi-atlas approach. Overall, the adaptive and the multi-atlas approaches performed similarly well against the MR-based quantification and would be a suitable replacements for PiB quantification when no MRI is available.
authors.affiliation: Preventative Health Flagship, CSIRO Digital Productivity and Services Flagship, Herston, Queensland, Australia. Electronic address: pierrick.bourgeat@csiro.au.
authors.forename: Pierrick
authors.initials: P
authors.lastname: Bourgeat
authors.affiliation: The Mental Health Research Institute, University of Melbourne, Parkville, Victoria, Australia; Department of Nuclear Medicine and Centre for PET, Austin Health, Heidelberg, Victoria, Australia.
authors.forename: Victor L
authors.initials: VL
authors.lastname: Villemagne
authors.affiliation: Preventative Health Flagship, CSIRO Digital Productivity and Services Flagship, Herston, Queensland, Australia; Department of Nuclear Medicine and Centre for PET, Austin Health, Heidelberg, Victoria, Australia.
authors.forename: Vincent
authors.initials: V
authors.lastname: Dore
authors.affiliation: Centre of Excellence for Alzheimer's Disease Research & Care, Edith Cowan University, Joondalup, Perth, Western Australia.
authors.forename: Belinda
authors.initials: B
authors.lastname: Brown
authors.affiliation: Preventative Health Flagship, CSIRO Materials Science & Engineering Flagship, Parkville, Victoria, Australia.
authors.forename: S Lance
authors.initials: SL
authors.lastname: Macaulay
authors.affiliation: Centre of Excellence for Alzheimer's Disease Research & Care, Edith Cowan University, Joondalup, Perth, Western Australia.
authors.forename: Ralph
authors.initials: R
authors.lastname: Martins
authors.affiliation: The Mental Health Research Institute, University of Melbourne, Parkville, Victoria, Australia.
authors.forename: Colin L
authors.initials: CL
authors.lastname: Masters
authors.affiliation: National Ageing Research Institute, University of Melbourne, Parkville, Victoria, Australia.
authors.forename: David
authors.initials: D
authors.lastname: Ames
authors.affiliation: Department of Psychiatry, University of Melbourne, Parkville, Victoria, Australia.
authors.forename: Kathryn
authors.initials: K
authors.lastname: Ellis
authors.affiliation: Department of Nuclear Medicine and Centre for PET, Austin Health, Heidelberg, Victoria, Australia.
authors.forename: Christopher C
authors.initials: CC
authors.lastname: Rowe
authors.affiliation: Preventative Health Flagship, CSIRO Digital Productivity and Services Flagship, Herston, Queensland, Australia.
authors.forename: Olivier
authors.initials: O
authors.lastname: Salvado
authors.affiliation: Preventative Health Flagship, CSIRO Digital Productivity and Services Flagship, Herston, Queensland, Australia.
authors.forename: Jurgen
authors.initials: J
authors.lastname: Fripp
mesh_terms: D000544:Alzheimer Disease / Q000175:diagnosis* / Q000378:metabolism / Q000473:pathology; D016229:Amyloid beta-Peptides / Q000378:metabolism; D000814:Aniline Compounds / Q000378:metabolism; D015415:Biomarkers; D066128:Gray Matter / Q000000981:diagnostic imaging* / Q000473:pathology*; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D059906:Neuroimaging / Q000379:methods*; D058225:Plaque, Amyloid / Q000175:diagnosis / Q000378:metabolism; D049268:Positron-Emission Tomography / Q000379:methods*; D013844:Thiazoles / Q000378:metabolism
chemical_list: C475519:2-(4'-(methylamino)phenyl)-6-hydroxybenzothiazole; D016229:Amyloid beta-Peptides; D000814:Aniline Compounds; D015415:Biomarkers; D013844:Thiazoles
keywords: Alzheimer's disease; PET quantification; Pittsburgh compound B