title: Cortical phase changes measured using 7-T MRI in subjects with subjective cognitive impairment, and their association with cognitive function.
abstract: Studies have suggested that, in subjects with subjective cognitive impairment (SCI), Alzheimer's disease (AD)-like changes may occur in the brain. Recently, an in vivo study has indicated the potential of ultra-high-field MRI to visualize amyloid-beta (Aβ)-associated changes in the cortex in patients with AD, manifested by a phase shift on T2 *-weighted MRI scans. The main aim of this study was to investigate whether cortical phase shifts on T2 *-weighted images at 7 T in subjects with SCI can be detected, possibly implicating the deposition of Aβ plaques and associated iron. Cognitive tests and T2 *-weighted scans using a 7-T MRI system were performed in 28 patients with AD, 18 subjects with SCI and 27 healthy controls (HCs). Cortical phase shifts were measured. Univariate general linear modeling and linear regression analysis were used to assess the association between diagnosis and cortical phase shift, and between cortical phase shift and the different neuropsychological tests, adjusted for age and gender. The phase shift (mean, 1.19; range, 1.00-1.35) of the entire cortex in AD was higher than in both SCI (mean, 0.85; range, 0.73-0.99; p < 0.001) and HC (mean, 0.94; range, 0.79-1.10; p < 0.001). No AD-like changes, e.g. increased cortical phase shifts, were found in subjects with SCI compared with HCs. In SCI, a significant association was found between memory function (Wechsler Memory Scale, WMS) and cortical phase shift (β = -0.544, p = 0.007). The major finding of this study is that, in subjects with SCI, an increased cortical phase shift measured at high field is associated with a poorer memory performance, although, as a group, subjects with SCI do not show an increased phase shift compared with HCs. This increased cortical phase shift related to memory performance may contribute to the understanding of SCI as it is still unclear whether SCI is a sign of pre-clinical AD. Copyright © 2014 John Wiley & Sons, Ltd.
authors.affiliation: C. J. Gorter Center for High-Field MRI, Leiden University Medical Center, Leiden, the Netherlands.|Department of Radiology, Leiden University Medical Center, Leiden, the Netherlands.
authors.forename: Sanneke
authors.initials: S
authors.lastname: van Rooden
authors.affiliation: C. J. Gorter Center for High-Field MRI, Leiden University Medical Center, Leiden, the Netherlands.|Department of Radiology, Leiden University Medical Center, Leiden, the Netherlands.
authors.forename: Mathijs
authors.initials: M
authors.lastname: Buijs
authors.affiliation: C. J. Gorter Center for High-Field MRI, Leiden University Medical Center, Leiden, the Netherlands.|Department of Radiology, Leiden University Medical Center, Leiden, the Netherlands.
authors.forename: Marjolein E
authors.initials: ME
authors.lastname: van Vliet
authors.affiliation: C. J. Gorter Center for High-Field MRI, Leiden University Medical Center, Leiden, the Netherlands.|Department of Radiology, Leiden University Medical Center, Leiden, the Netherlands.
authors.forename: Maarten J
authors.initials: MJ
authors.lastname: Versluis
authors.affiliation: C. J. Gorter Center for High-Field MRI, Leiden University Medical Center, Leiden, the Netherlands.|Department of Radiology, Leiden University Medical Center, Leiden, the Netherlands.
authors.forename: Andrew G
authors.initials: AG
authors.lastname: Webb
authors.affiliation: Department of Gerontology and Geriatrics, Leiden University Medical Center, Leiden, the Netherlands.
authors.forename: Ania M
authors.initials: AM
authors.lastname: Oleksik
authors.affiliation: Department of Neuropsychology, Leiden University Medical Center, Leiden, the Netherlands.
authors.forename: Lotte
authors.initials: L
authors.lastname: van de Wiel
authors.affiliation: Department of Neuropsychology, Leiden University Medical Center, Leiden, the Netherlands.
authors.forename: Huub A M
authors.initials: HA
authors.lastname: Middelkoop
authors.affiliation: Department of Gerontology and Geriatrics, Leiden University Medical Center, Leiden, the Netherlands.|Department of Gerontology and Geriatrics, Bronovo Hospital, Den Haag, the Netherlands.
authors.forename: Gerard Jan
authors.initials: GJ
authors.lastname: Blauw
authors.affiliation: Department of Gerontology and Geriatrics, Diaconessen Hospital, Leiden, the Netherlands.
authors.forename: Annelies W E
authors.initials: AW
authors.lastname: Weverling-Rynsburger
authors.affiliation: Alzheimer Center and Department of Neurology, Neuroscience Campus Amsterdam, VU University Medical Center, Amsterdam, the Netherlands.
authors.forename: Jeroen D C
authors.initials: JD
authors.lastname: Goos
authors.affiliation: Alzheimer Center and Department of Neurology, Neuroscience Campus Amsterdam, VU University Medical Center, Amsterdam, the Netherlands.|Department of Epidemiology and Biostatistics, VU University Medical Center, Amsterdam, the Netherlands.
authors.forename: Wiesje M
authors.initials: WM
authors.lastname: van der Flier
authors.affiliation: Alzheimer Center and Department of Neurology, Neuroscience Campus Amsterdam, VU University Medical Center, Amsterdam, the Netherlands.
authors.forename: Ted
authors.initials: T
authors.lastname: Koene
authors.affiliation: Alzheimer Center and Department of Neurology, Neuroscience Campus Amsterdam, VU University Medical Center, Amsterdam, the Netherlands.
authors.forename: Philip
authors.initials: P
authors.lastname: Scheltens
authors.affiliation: Department of Radiology, VU University Medical Center, Amsterdam, the Netherlands.
authors.forename: Frederik
authors.initials: F
authors.lastname: Barkhof
authors.affiliation: Division of Human Nutrition, Wageningen University, Wageningen, the Netherlands.
authors.forename: Ondine
authors.initials: O
authors.lastname: van de Rest
authors.affiliation: Department of Molecular Epidemiology, Leiden University Medical Center, Leiden, the Netherlands.
authors.forename: P Eline
authors.initials: PE
authors.lastname: Slagboom
authors.affiliation: C. J. Gorter Center for High-Field MRI, Leiden University Medical Center, Leiden, the Netherlands.|Department of Radiology, Leiden University Medical Center, Leiden, the Netherlands.
authors.forename: Mark A
authors.initials: MA
authors.lastname: van Buchem
authors.affiliation: C. J. Gorter Center for High-Field MRI, Leiden University Medical Center, Leiden, the Netherlands.|Department of Radiology, Leiden University Medical Center, Leiden, the Netherlands.
authors.forename: Jeroen
authors.initials: J
authors.lastname: van der Grond
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000000981:diagnostic imaging / Q000473:pathology* / Q000503:physiopathology*; D003071:Cognition; D060825:Cognitive Dysfunction / Q000000981:diagnostic imaging / Q000473:pathology* / Q000503:physiopathology*; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007090:Image Interpretation, Computer-Assisted / Q000379:methods; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
keywords: AD pathology; Alzheimer's disease; brain imaging; cognition; human 7-T MRI; phase; subjective cognitive impairment