Individual cerebral metabolic deficits in Alzheimer's disease and amnestic mild cognitive impairment: an FDG PET study.
OBJECTIVE
The purpose of the study was the identification of group and individual subject patterns of cerebral glucose metabolism (CMRGlu) in patients with Alzheimer's disease (AD) and with amnestic mild cognitive impairment (aMCI).


METHODS
[(18)F]fluorodeoxyglucose positron emission tomography (PET) studies and neuropsychological tests were performed in 16 aMCI patients (ten women, age 75+/-8 years) and in 14 AD patients (ten women, age 75+/-9 years). Comparisons between patient subgroups and with a control population were performed using Statistical Parametric Mapping.


RESULTS
Clusters of low CMRGlu were observed bilaterally in the posterior cingulate cortex (PCC), in the precuneus, in the inferior parietal lobule and middle temporal gyrus of AD patients. In aMCI patients, reduced CMRGlu was found only in PCC. Areas of low CMRGlu in PCC were wider in AD compared to aMCI and extended to the precuneus, while low CMRGlu was found in the lateral parietal cortex in AD but not in aMCI patients. Individual subject pattern analysis revealed that 86% of AD patients had low CMRGlu in the PCC (including the precuneus in 71%), 71% in the temporal cortex, 64% in the parietal cortex and 35% in the frontal cortex. Among the aMCI patients, 56% had low CMRGlu in the PCC, 44% in the temporal cortex, 18% in the frontal cortex and none in the parietal cortex.


CONCLUSIONS
This study demonstrates that both AD and aMCI patients have highly heterogeneous metabolic impairment. This potential of individual metabolic PET imaging in patients with AD and aMCI may allow timely identification of brain damage on individual basis and possibly help planning tailored early interventions.
Del Sole
Angelo
A
Institute of Radiological Sciences, University of Milan, Unit of Nuclear Medicine, Hospital San Paolo, Via Antonio di Rudinì, 8, 20142 Milan, Italy.
Clerici
Francesca
F
Chiti
Arturo
A
Lecchi
Michela
M
Mariani
Claudio
C
Maggiore
Laura
L
Mosconi
Lisa
L
Lucignani
Giovanni
G
D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000000981:diagnostic imaging* / Q000378:metabolism*; D000647:Amnesia / Q000000981:diagnostic imaging* / Q000378:metabolism*; D001921:Brain / Q000000981:diagnostic imaging* / Q000378:metabolism*; D016022:Case-Control Studies; D003072:Cognition Disorders / Q000000981:diagnostic imaging* / Q000378:metabolism*; D005260:Female; D005462:Fluorine Radioisotopes; D019788:Fluorodeoxyglucose F18; D005947:Glucose / Q000378:metabolism; D006801:Humans; D008297:Male; D049268:Positron-Emission Tomography; D019275:Radiopharmaceuticals
D005462:Fluorine Radioisotopes; D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18; D005947:Glucose