Beta-amyloid burden in the temporal neocortex is related to hippocampal atrophy in elderly subjects without dementia.
OBJECTIVE
To investigate whether global and regional beta-amyloid (Abeta) burden as measured with 11C Pittsburgh compound B (PIB) PET is associated with hippocampal atrophy characterized using MRI in healthy controls and patients with amnestic mild cognitive impairment (aMCI) or Alzheimer disease (AD).


METHODS
Ninety-two elderly healthy controls, 32 subjects with aMCI, and 35 patients with AD were imaged using 11C-PIB PET and MRI. Hippocampal volume was measured and PIB standardized uptake value ratio was extracted after partial volume correction within 41 regions of interest. Global, regional, and voxel-based correlations between PIB and hippocampal volume were computed for each group.


RESULTS
In healthy control participants with elevated neocortex PIB retention, significant correlation was found between PIB retention in the inferior temporal region and hippocampal volume using both region-based and voxel-based approaches. No correlation was found in any other group.


CONCLUSIONS
The strong correlation between hippocampal atrophy and beta-amyloid (Abeta) burden in the Pittsburgh compound B-positive healthy control group suggests that Abeta deposition in the inferior temporal neocortex is related to hippocampal synaptic and neuronal degeneration.
Bourgeat
P
P
CSIRO Preventative Health National Research Flagship ICTC, The Australian e-Health Research Centre-BioMedIA, Royal Brisbane and Women's Hospital, Herston, Queensland, Australia. pierrick.bourgeat@csiro.au
Chételat
G
G
Villemagne
V L
VL
Fripp
J
J
Raniga
P
P
Pike
K
K
Acosta
O
O
Szoeke
C
C
Ourselin
S
S
Ames
D
D
Ellis
K A
KA
Martins
R N
RN
Masters
C L
CL
Rowe
C C
CC
Salvado
O
O
D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000378:metabolism / Q000473:pathology; D000465:Algorithms; D016229:Amyloid beta-Peptides / Q000378:metabolism*; D000814:Aniline Compounds; D001284:Atrophy / Q000000981:diagnostic imaging / Q000378:metabolism / Q000473:pathology*; D015415:Biomarkers / Q000032:analysis / Q000378:metabolism; D001931:Brain Mapping / Q000379:methods; D002250:Carbon Radioisotopes; D015331:Cohort Studies; D018450:Disease Progression; D005260:Female; D006624:Hippocampus / Q000000981:diagnostic imaging / Q000378:metabolism / Q000473:pathology*; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008875:Middle Aged; D019579:Neocortex / Q000000981:diagnostic imaging / Q000378:metabolism / Q000473:pathology*; D009410:Nerve Degeneration / Q000000981:diagnostic imaging / Q000378:metabolism / Q000473:pathology; D058225:Plaque, Amyloid / Q000378:metabolism / Q000473:pathology*; D049268:Positron-Emission Tomography / Q000379:methods; D012720:Severity of Illness Index; D013702:Temporal Lobe / Q000000981:diagnostic imaging / Q000378:metabolism / Q000473:pathology*; D013844:Thiazoles
C475519:2-(4'-(methylamino)phenyl)-6-hydroxybenzothiazole; D016229:Amyloid beta-Peptides; D000814:Aniline Compounds; D015415:Biomarkers; D002250:Carbon Radioisotopes; D013844:Thiazoles