English
Related papers

Related papers: Travelling Wave Magnetic Resonance Imaging at 3 Te…

200 papers

Standard coils can cause inhomogeneities due to the standing wave patterns at ultra high field MRI. This B1 inhomogeneity can be overcome using the travelling-wave MRI (twMRI) approach. The ma- jority of twMRI research has been done with…

Medical Physics · Physics 2015-11-12 Fabian Vazquez , Oscar Marrufo , Rodrigo Martin , Sergio Solis , Alfredo O. Rodriguez

The travelling-wave MRI approach is an alternative to overcome the B1 inhomogeneity at UHF MRI for human applications. More recently, this concept has been also used with animal MR imagers. We used a parallel-plate waveguide and a…

Medical Physics · Physics 2018-03-15 F. Vazquez , S. E. Solis-Najera , J. Lazovic , L. M. Zopf , R. Martin , L. Medina , O. Marrufo , A. O. Rodriguez

We demonstrate an experimental method for direct 2D and 3D imaging of magnetic radio-frequency (rf) field distribution in metal-dielectric structures based on traveling wave (TW) magnetic resonance imaging (MRI) at ultra-high field (> 7T).…

Instrumentation and Detectors · Physics 2016-01-19 A. Tonyushkin , D. K. Deelchand , P. -F. Van de Moortele , G. Adriany , A. Kiruluta

Recently, the concept of traveling-wave NMR/MRI was introduced by Brunner et al. (Nature 457, 994-992 (2009)), who demonstrated MR images acquired using radio frequency (RF) waves propagating down the bore of an MR scanner. One of the…

Instrumentation and Detectors · Physics 2013-06-11 Joel A. Tang , Graham C. Wiggins , Daniel K. Sodickson , Alexej Jerschow

This research focuses on the design and evaluation of an ultrathin cylindrical metasurface for improving the transmit efficiency of traveling-wave magnetic resonance imaging (MRI) of the human brain. To improve efficiency, we matched a…

Subwavelength-slotted parallel plate waveguides exhibit a localized electromagnetic resonance bound to the slits at a frequency slightly below the transverse electric cutoff [R. Merlin, Phys. Rev. X 2, 031015 (2012)]. The resonance is…

Optics · Physics 2016-11-23 Meredith Henstridge , J. Zhou , L. Jay Guo , R. Merlin

Magnetic resonance imaging (MRI) scanners have advanced significantly, with a growing use of highfield 3 T systems. This evolution gives rise to safety concerns for healthcare personnel working in proximity to MRI equipment. While…

A numerical study of the radiation in coupled bent waveguides is presented. Such arrangements of curved waveguides in reduced radiation-loss configurations can be used to enhance the quality factor of integrated micro-resonators. 3D full…

Optics · Physics 2019-06-26 Pedro Chamorro-Posada

In this paper, we introduce and study parallel-plate waveguides formed by two penetrable metasurfaces having arbitrary isotropic sheet impedances. We investigate guided modes of this structure and derive the corresponding dispersion…

Applied Physics · Physics 2020-04-22 X. Ma , M. S. Mirmoosa , S. A. Tretyakov

An essential part of nondestructive testing and experimental modeling of waveguides is the decomposition of propagating wave patterns. The traveling wave ratio is a measure of partial reflections assisting in quantifying the pureness of a…

Applied Physics · Physics 2021-01-06 Yoav Vered , Izhak Bucher

This study explores the potential of a novel material platform combining Gallium Selenide (GaSe) with a \b{eta}-Ga2O3 substrate and Al2O3 cladding for advanced photonic waveguides. The numerical investigation of the optical performance of…

Purpose: To develop a cardiac T1 mapping method for free-breathing 3D T1 mapping of the whole heart at 3T with transmit B1 (B1+) correction Methods: A free-breathing, ECG-gated inversion recovery sequence with spoiled gradient-echo readout…

Medical Physics · Physics 2021-11-16 Paul Kyu Han , Thibault Marin , Yanis Djebra , Vanessa Landes , Yue Zhuo , Georges El Fakhri , Chao Ma

The technology of magnetic resonance imaging is developing towards higher magnetic fields to improve resolution and contrast. However, whole-body imaging at 7 T or even higher fields remains challenging due to wave interference, tissue…

Applied Physics · Physics 2020-01-29 G. Solomakha , J. T. Svejda , C. van Leeuwen , A. Rennings , A. J. Raaijmakers , S. Glybovski , D. Erni

Recent studies have developed tunable topological elastic metamaterials to maximize performance in the presence of varying external conditions, adapt to changing operating requirements, and enable new functionalities such as a programmable…

Applied Physics · Physics 2021-01-19 Patrick Dorin , Kon-Well Wang

This study presents the design, simulation, and experimental validation of a novel multimodal concentric surface coil for MR imaging, developed to achieve higher B1 field efficiency while maintaining low SAR for enhanced imaging…

Medical Physics · Physics 2025-08-21 Yunkun Zhao , Aditya A Bhosale , Xiaoliang Zhang

We propose and experimentally demonstrate a photonic routing architecture that can efficiently utilize the space of multi-plane (3D) photonic integration. A wafer with three planes of amorphous silicon waveguides was fabricated and…

Applied Physics · Physics 2017-09-01 Jeff Chiles , Sonia Buckley , Nima Nader , Sae Woo Nam , Richard P. Mirin , Jeffrey M. Shainline

Multicomponent T2-mapping using a gradient and spin-echo (GraSE) acquisition has become standard for myelin water imaging at 3T. Higher magnetic field strengths promise SNR benefits but face specific absorption rate limits and shortened T2…

Medical Physics · Physics 2021-05-14 Vanessa Wiggermann , Alex MacKay , Alexander Rauscher , Gunther Helms

The Spreading Projection Algorithm for Rapid K-space samplING, or SPARKLING, is an optimization-driven method that has been recently introduced for accelerated 2D T2*-w MRI using compressed sensing. It has then been extended to address 3D…

Distributed, Parallel, and Cluster Computing · Computer Science 2021-08-26 Chaithya G R , Pierre Weiss , Guillaume Daval-Frérot , Aurélien Massire , Alexandre Vignaud , Philippe Ciuciu

It has been recently shown how computing operations such as high-speed switching, routing, and solving partial differential equations can be performed by exploiting perfect splitting of electromagnetic waves in networks of waveguides from…

Classical Physics · Physics 2023-12-22 William Rogers , Christian Johnson-Richards , Alex Yakovlev , Victor Pacheco-Peña

We present experimental and numerical studies of localized terahertz surface waves on a subwavelength-thick metamaterial film consisting of in-plane split-ring resonators. A simple and intuitive model is derived that describes the…

Optics · Physics 2010-10-06 Benjamin Reinhard , Oliver Paul , Rene Beigang , Marco Rahm
‹ Prev 1 2 3 10 Next ›