title: Separation of β-amyloid binding and white matter uptake of (18)F-flutemetamol using spectral analysis.
abstract: The kinetic components of the β-amyloid ligand (18)F-flutemetamol binding in grey and white matter were investigated through spectral analysis, and a method developed for creation of parametric images separating grey and white matter uptake. Tracer uptake in grey and white matter and cerebellar cortex was analyzed through spectral analysis in six subjects, with (n=4) or without (n=2) apparent β-amyloid deposition, having undergone dynamic (18)F-flutemetamol scanning with arterial blood sampling. The spectra were divided into three components: slow, intermediate and fast basis function rates. The contribution of each of the components to total volume of distribution (VT) was assessed for different tissue types. The slow component dominated in white matter (average 90%), had a higher contribution to grey matter VT in subjects with β-amyloid deposition (average 44%) than without (average 6%) and was absent in cerebellar cortex, attributing the slow component of (18)F-flutemetamol uptake in grey matter to β-amyloid binding. Parametric images of voxel-based spectral analysis were created for VT, the slow component and images segmented based on the slow component contribution; confirming that grey matter and white matter uptake can be discriminated on voxel-level using a threshold for the contribution from the slow component to VT.
authors.affiliation: Department of Surgical Sciences, Uppsala University Uppsala, Sweden.
authors.forename: Kerstin
authors.initials: K
authors.lastname: Heurling
authors.affiliation: GE Healthcare Amersham, UK.
authors.forename: Christopher
authors.initials: C
authors.lastname: Buckley
authors.affiliation: Department of Neurosciences, KU Leuven and University Hospitals Leuven Leuven, Belgium.
authors.forename: Rik
authors.initials: R
authors.lastname: Vandenberghe
authors.affiliation: Department of Imaging and Pathology, KU Leuven and University Hospitals Leuven Leuven, Belgium.
authors.forename: Koen Van
authors.initials: KV
authors.lastname: Laere
authors.affiliation: Department of Surgical Sciences, Uppsala University Uppsala, Sweden ; Medical Physics, Uppsala University Hospital Uppsala, Sweden.
authors.forename: Mark
authors.initials: M
authors.lastname: Lubberink
keywords: Alzheimer’s; kinetic modelling; molecular imaging; positron emission tomography; white matter disease