𝔖 Bobbio Scriptorium
✦   LIBER   ✦

Torque free asymmetric gradient coils for echo planar imaging

✍ Scribed by A. M. Abduljalil; A. H. Aletras; Pierre-Marie Robitaille

Publisher
John Wiley and Sons
Year
1994
Tongue
English
Weight
454 KB
Volume
31
Category
Article
ISSN
0740-3194

No coin nor oath required. For personal study only.

✦ Synopsis

Abstract

In this work, we present a new torque‐free asymmetric gradient coil that is capable of generating high quality axial, sagittal, and coronal echo planar images of the human head. This gradient set was calculated using the Biot‐Savart law and least square approaches to optimize the field in the region of interest and to minimize net torques. The resulting structure has excellent shoulder‐to‐coil clearance and, as such, has the advantage of providing good patient access to the linear portion of the gradient while minimizing patient discomfort from claustrophobia.

📜 SIMILAR VOLUMES

Concomitant field terms for asymmetric g
Concomitant field terms for asymmetric gradient coils: Consequences for diffusion, flow, and echo-planar imaging
✍ C. Meier; M. Zwanger; T. Feiweier; D. Porter 📂 Article 📅 2008 🏛 John Wiley and Sons 🌐 English ⚖ 396 KB

## Abstract As a consequence of the Maxwell equations, linear field gradients are accompanied by additional spatially dependent field components. A description of the Maxwell field terms is presented which explicitly takes into account the asymmetry of the gradient coil. It is shown both theoretica

Asymmetrical gradient coil for head imag
Asymmetrical gradient coil for head imaging
✍ D. Tomasi; R.F. Xavier; B. Foerster; H. Panepucci; A. Tannús; E.L. Vidoto 📂 Article 📅 2002 🏛 John Wiley and Sons 🌐 English ⚖ 450 KB

## Abstract This work presents a novel approach to develop dedicated transverse gradient coils for head imaging. The proposed coil design is based on the stochastic optimization of an asymmetrical stream function and improves the matching between the region‐of‐interest and the homogeneous gradient

Echo-planar imaging with asymmetric grad
Echo-planar imaging with asymmetric gradient modulation and inner-volume excitation
✍ David A. Feinberg; Robert Turner; Peter D. Jakab; Markus Von Kienlin 📂 Article 📅 1990 🏛 John Wiley and Sons 🌐 English ⚖ 419 KB

## Abstract Single‐shot echo‐planar imaging is notoriously vulnerable to image artifacts, arising from the necessity of alternate echo time reversal during image reconstruction and from static field inhomogeneity. A technique for overcoming these problems, which further permits imaging on systems w

Myocardial first pass perfusion: Steady-
Myocardial first pass perfusion: Steady-state free precession versus spoiled gradient echo and segmented echo planar imaging
✍ Yi Wang; Khurram Moin; Olakunle Akinboboye; Nathaniel Reichek 📂 Article 📅 2005 🏛 John Wiley and Sons 🌐 English ⚖ 227 KB

## Abstract The imaging sequences used in first pass (FP) perfusion to date have important limitations in contrast‐to‐noise ratio (CNR), temporal and spatial resolution, and myocardial coverage. As a result, controversy exists about optimal imaging strategies for FP myocardial perfusion. Since imag

Design of flyback echo-planar readout gr
Design of flyback echo-planar readout gradients for magnetic resonance spectroscopic imaging
✍ Charles H. Cunningham; Daniel B. Vigneron; Albert P. Chen; Duan Xu; Sarah J. Nel 📂 Article 📅 2005 🏛 John Wiley and Sons 🌐 English ⚖ 223 KB

## Abstract The spatial resolution of conventional magnetic resonance spectroscopic imaging‐(MRSI) is typically coarse, mainly due to SNR limitations. The increased signal available with higher field scanners and new array coils now permits higher spatial resolution, but conventional chemical shift

Avoiding peripheral nerve stimulation: G
Avoiding peripheral nerve stimulation: Gradient waveform criteria for optimum resolution in echo-planar imaging
✍ Paul R. Harvey; Sir Peter Mansfield 📂 Article 📅 1994 🏛 John Wiley and Sons 🌐 English ⚖ 483 KB

## Abstract Adaptation of Mansfield and Harvey's theory of magnetically induced neural stimulation indicates that, for trapezoidal gradient waveforms and at the relatively low modulation frequencies commonly used in echo‐planar imaging, an increase in rise time even to the point of creating a trian