title: Practical improvements in the design of high permittivity pads for dielectric shimming in neuroimaging at 7T.
abstract: Improvements are proposed for practical design and use of high permittivity materials in high field neuroimaging in three different areas: (i) a simple formula to predict the permittivity of tri-component aqueous-based perovskite suspensions with relative permittivities between 110 and 300, (ii) characterization of addition of a hydroxyethyl-cellulose gelling agent to improve the long-term stability and material properties of "dielectric pads", and (iii) investigation of the integration of, for example, headphones into the dielectric pads to increase patient comfort within tightly-fitting receive coil arrays.
authors.affiliation: C.J. Gorter Center for High Field MRI, Department of Radiology, Leiden University Medical Center, Leiden, Netherlands.
authors.forename: T P A
authors.initials: TPA
authors.lastname: O'Reilly
authors.affiliation: C.J. Gorter Center for High Field MRI, Department of Radiology, Leiden University Medical Center, Leiden, Netherlands. Electronic address: a.webb@lumc.nl.
authors.forename: A G
authors.initials: AG
authors.lastname: Webb
authors.affiliation: C.J. Gorter Center for High Field MRI, Department of Radiology, Leiden University Medical Center, Leiden, Netherlands.
authors.forename: W M
authors.initials: WM
authors.lastname: Brink
mesh_terms: D006801:Humans; D007089:Image Enhancement; D008279:Magnetic Resonance Imaging; D059906:Neuroimaging
keywords: B(1) homogeneity; High permittivity materials; Induced currents; Matrix stabilization; Mixing rules