Cited by 958Dementia and Cognitive Impairment ResearchAlzheimer's disease research and treatmentsMedical Imaging Techniques and Applications

11C PiB and structural MRI provide complementary information in imaging of Alzheimer's disease and amnestic mild cognitive impairment

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Jack, Clifford R., Lowe, Val J., Senjem, Matthew L., Weigand, Stephen D., Kemp, Bradley J., Shiung, Maria M., Knopman, David S., Boeve, Bradley F. +3 more·2008·Brain

Abstract

To date, most diagnostic imaging comparisons between amyloid labelling ligands and other imaging modalities have been between the use of amyloid labelling ligand (11)C Pittsburgh Compound B (PiB) and FDG-PET. Our objectives were to compare cognitive performance and diagnostic group-wise discrimination between cognitively normal, amnestic mild cognitive impairment (MCI) and Alzheimer's disease subjects with MRI-based measures of hippocampal volume and PiB retention, and secondly to evaluate the topographic distribution of PiB retention and grey matter loss using 3D voxel-wise methods. Twenty cognitively normal, 17 amnestic MCI and 8 probable Alzheimer's disease subjects were imaged with both MRI and PiB. PiB retention was quantified as the ratio of uptake in cortical to cerebellar regions of interest (ROIs) 40-60 min post-injection. A global cortical PiB retention summary measure was derived from six cortical ROIs. Statistical parametric mapping (SPM) and voxel-based morphometry (VBM) were used to evaluate PiB retention and grey matter loss on a 3D voxel-wise basis. Alzheimer's disease subjects had high global cortical PiB retention and low hippocampal volume; most cognitively normal subjects had low PiB retention and high hippocampal volume; and on average amnestic MCI subjects were intermediate on both PiB and hippocampal volume. A target-to-cerebellar ratio of 1.5 was used to designate subjects with high or low PiB cortical retention. All Alzheimer's disease subjects fell above this ratio, as did 6 out of 20 cognitively normal subjects and 9 out of 17 MCI subjects, indicating bi-modal PiB retention in the latter two groups. Interestingly, we found no consistent differences in learning and memory performance between high versus low PiB cognitively normal or amnestic MCI subjects. The SPM/VBM voxel-wise comparisons of Alzheimer's disease versus cognitively normal subjects provided complementary information in that clear and meaningful similarities and differences in topographical distribution of amyloid deposition and grey matter loss were shown. The frontal lobes had high PiB retention with little grey matter loss, anteromedial temporal areas had low PiB retention with significant grey matter loss, whereas lateral temporoparietal association cortex displayed both significant PiB retention and grey matter loss. A voxel-wise SPM conjunction analysis revealed that subjects with high PiB retention shared a common PiB retention topographical pattern regardless of clinical category, and this matched that of amyloid plaque distribution from autopsy studies of Alzheimer's disease. Both global cortical PiB retention and hippocampal volumes demonstrated significant correlation in the expected direction with cognitive testing performance; however, correlations were stronger with MRI than PiB. Pair-wise inter-group diagnostic separation was significant for all group-wise pairs for both PiB and hippocampal volume with the exception of the comparison of cognitively normal versus amnestic MCI, which was not significant for PiB. PiB and MRI provided complementary information such that clinical diagnostic classification using both methods was superior to using either in isolation.

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Crossref · 10.1093/brain/awm336

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  • A similar proportion of individuals clinically diagnosed as AD dementia have normal amyloid PET or CSF Aβ42 studies.

    “and a similar proportion has normal amyloid PET or CSF Aβ42 studies [53–62].”

    From NIA‐AA Research Framework: Toward a biological definition of Alzheimer's disease (2018) · cites this paper as [55]

    The Introduction says nearly all clinically diagnosed AD subjects show PiB retention, which leaves open a small minority with normal amyloid PET findings. The Discussion reports that all eight AD subjects in this study had high PiB retention. The paper does not establish a ‘similar proportion’ with normal findings or report a proportion with normal CSF Aβ42. (LLM, conf=0.80)

    Experimental — accuracy not yet measured
  • PIB uptake and CSF Aβ42 are reliable surrogate markers of amyloid plaque pathology in living subjects.

    “A preponderance of evidence supports the interpretation that PIB uptake and CSF Aβ42 are reliable surrogate markers of amyloid plaque pathology in living subjects (15-19).”

    From Human ApoE isoforms differentially regulate brain amyloid-β peptide clearance (2011) · cites this paper as [16]

    The Introduction (page unavailable) describes PiB as an in vivo amyloid-plaque tracer whose binding corresponds to plaque distribution. It also reports an inverse correlation between cortical PiB uptake and CSF Aβ42, but does not establish that CSF Aβ42 is itself a reliable surrogate for plaque pathology. The Discussion (page unavailable) calls PiB an accurate marker of brain fibrillar amyloid a current expectation. (LLM, conf=0.83)

    Experimental — accuracy not yet measured
  • A similar proportion of cognitively unimpaired elderly persons has abnormal amyloid biomarkers.

    “and a similar proportion has abnormal amyloid biomarkers [33,53–55,60,70–73].”
  • Elevated CSF P-tau, with a mean level of 31 pg/mL, is seen in FTD owing to a genetic variant in the MAPT gene.

    “It was reported that elevated levels of CSF P-tau, with a mean level of 31 pg/mL, is seen in FTD owing to a genetic variant in the MAPT gene,46 which produces the protein product tau.”

    From Association of Cognitive and Behavioral Features Between Adults With Tuberous Sclerosis and Frontotemporal Dementia (2020) · cites this paper as [46]

    The Introduction discusses CSF amyloid beta 42 and PiB binding in frontotemporal dementia, but not CSF P-tau levels in FTD. Searches for the reported 31 pg/mL mean and for MAPT-related FTD found no passage addressing either point in our copy. (LLM, conf=0.75)

    Experimental — accuracy not yet measured

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Cited by

Sorted by citations

Authors
Jack, C. R., Lowe, V. J., Senjem, M. L., Weigand, S. D., Kemp, B. J., Shiung, M. M., Knopman, D. S., Boeve, B. F., Klunk, W. E., Mathis, C. A., & Petersen, R. C.
Affiliations
Mayo Clinic (US)
Venue
Brain
Published
2008-02-07
Volume
131
Issue
3
Pages
665-680
ISSN
  • 0006-8950 (ISSN-L)
  • 1460-2156
OpenAlex
W2148079076
Cited by
958
References
17
Citations by year
2026: 17 · 2025: 25 · 2024: 32 · 2023: 32 · 2022: 48 · 2021: 57 · 2020: 46 · 2019: 57 · 2018: 44 · 2017: 49 · 2016: 49 · 2015: 49 · 2014: 72 · 2013: 83 · 2012: 76
FWCI
52.00
Type
journal article
Language
en
Open access
Licence
cc-by-nc
Locations
  • Brain (publishedVersion, cc-by-nc)
  • PubMed (publishedVersion)
  • PubMed Central (acceptedVersion)
Funders
  • Mayo Foundation for Medical Education and Research (AG16574)
  • National Institutes of Health (AG11378, AG06786, R01 AG11378, AG16574)
  • National Institute on Aging (R01AG11378, P50‐AG16574, U01AG06786, AG 16574, U01AG006786, R01AG011378, AG-11378, P50AG016574)
  • National Center for Research Resources (C06RR018898)
Topics
  • Health Sciences › Medicine › Psychiatry and Mental health › Dementia and Cognitive Impairment Research
  • Health Sciences › Medicine › Physiology › Alzheimer's disease research and treatments
  • Health Sciences › Medicine › Radiology, Nuclear Medicine and Imaging › Medical Imaging Techniques and Applications
Keywords
11C-Pittsburgh compound B, amyloid PET, Alzheimer's disease, amnestic mild cognitive impairment, hippocampal volume, gray matter loss, voxel-based morphometry, statistical parametric mapping, cognitive performance, learning and memory, multimodal neuroimaging, FDG-PET comparison
MeSH terms
Aged, Alzheimer Disease, Amnesia, Aniline Compounds, Brain Mapping, Carbon Radioisotopes, Cognition Disorders, Diagnosis, Differential, Female, Hippocampus, Humans, Longitudinal Studies, Magnetic Resonance Imaging, Male, Middle Aged, Neuropsychological Tests, Thiazoles, Positron-Emission Tomography

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