title: Effects of coplanar shielding for high field MRI.
abstract: This work investigates the efficacy of "coplanar shielding," in which copper shields are oriented concentric and coplanar to the RF coils rather than implemented as a full ground plane behind them. Following FDTD simulations to determine optimal shielding parameters, two coil geometries were constructed: a circular loop surface coil and a half-volume five-element receive array. Each was evaluated using bench measurements with and without coplanar shielding. Imaging, including accelerated SENSE imaging, was performed with the shielded and unshielded receive arrays on a whole-body 7T scanner. Results from modeled and fabricated coils showed good agreement with improvements in Q factors for all cases. Imaging showed substantial improvements in SNR and g-factors for the coplanar shielded array.
authors.forename: Joseph V
authors.initials: JV
authors.lastname: Rispoli
authors.forename: Matthew D
authors.initials: MD
authors.lastname: Wilcox
authors.forename: Samantha
authors.initials: S
authors.lastname: By
authors.forename: Steven M
authors.initials: SM
authors.lastname: Wright
authors.forename: Mary P
authors.initials: MP
authors.lastname: McDougall
mesh_terms: D008279:Magnetic Resonance Imaging / Q000295:instrumentation / Q000379:methods; D008962:Models, Theoretical; D019047:Phantoms, Imaging