RT Journal Article SR Electronic T1 Progressive Disintegration of Brain Networking from Normal Aging to Alzheimer Disease: Analysis of Independent Components of 18F-FDG PET Data JF Journal of Nuclear Medicine JO J Nucl Med FD Society of Nuclear Medicine SP 1132 OP 1139 DO 10.2967/jnumed.116.184309 VO 58 IS 7 A1 Marco Pagani A1 Alessandro Giuliani A1 Johanna Öberg A1 Fabrizio De Carli A1 Silvia Morbelli A1 Nicola Girtler A1 Dario Arnaldi A1 Jennifer Accardo A1 Matteo Bauckneht A1 Francesca Bongioanni A1 Andrea Chincarini A1 Gianmario Sambuceti A1 Cathrine Jonsson A1 Flavio Nobili YR 2017 UL http://jnm.snmjournals.org/content/58/7/1132.abstract AB Brain connectivity has been assessed in several neurodegenerative disorders investigating the mutual correlations between predetermined regions or nodes. Selective breakdown of brain networks during progression from normal aging to Alzheimer disease dementia (AD) has also been observed. Methods: We implemented independent-component analysis of 18F-FDG PET data in 5 groups of subjects with cognitive states ranging from normal aging to AD—including mild cognitive impairment (MCI) not converting or converting to AD—to disclose the spatial distribution of the independent components in each cognitive state and their accuracy in discriminating the groups. Results: We could identify spatially distinct independent components in each group, with generation of local circuits increasing proportionally to the severity of the disease. AD-specific independent components first appeared in the late-MCI stage and could discriminate converting MCI and AD from nonconverting MCI with an accuracy of 83.5%. Progressive disintegration of the intrinsic networks from normal aging to MCI to AD was inversely proportional to the conversion time. Conclusion: Independent-component analysis of 18F-FDG PET data showed a gradual disruption of functional brain connectivity with progression of cognitive decline in AD. This information might be useful as a prognostic aid for individual patients and as a surrogate biomarker in intervention trials.