Inductive measurement of magnetic field gradients for magnetic resonance imaging

1998 ◽  
Vol 69 (6) ◽  
pp. 2400-2405 ◽  
Author(s):  
Viliam Senaj ◽  
Geneviève Guillot ◽  
Luc Darrasse
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Field ◽  
Magnetic Resonance ◽  
Resonance Imaging ◽  
Field Gradients ◽  
Magnetic Field Gradients ◽  
Inductive Measurement

Nuclear magnetic resonance microscopy

1989 ◽  
Vol 47 ◽  
pp. 828-829
Author(s):  
Paul C. Lauterbur
Keyword(s):  
Magnetic Field ◽  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Magnetic Fields ◽  
Signal To Noise ◽  
Field Gradients ◽  
Useful Signal ◽  
Magnetic Field Gradients ◽  
Observation Times ◽  
Nuclear Magnetic

Nuclear magnetic resonance imaging can reach microscopic resolution, as was noted many years ago, but the first serious attempt to explore the limits of the possibilities was made by Hedges. Resolution is ultimately limited under most circumstances by the signal-to-noise ratio, which is greater for small radio receiver coils, high magnetic fields and long observation times. The strongest signals in biological applications are obtained from water protons; for the usual magnetic fields used in NMR experiments (2-14 tesla), receiver coils of one to several millimeters in diameter, and observation times of a number of minutes, the volume resolution will be limited to a few hundred or thousand cubic micrometers. The proportions of voxels may be freely chosen within wide limits by varying the details of the imaging procedure. For isotropic resolution, therefore, objects of the order of (10μm) may be distinguished.Because the spatial coordinates are encoded by magnetic field gradients, the NMR resonance frequency differences, which determine the potential spatial resolution, may be made very large. As noted above, however, the corresponding volumes may become too small to give useful signal-to-noise ratios. In the presence of magnetic field gradients there will also be a loss of signal strength and resolution because molecular diffusion causes the coherence of the NMR signal to decay more rapidly than it otherwise would. This phenomenon is especially important in microscopic imaging.

Magnetic resonance imaging: effects of magnetic field strength.

Radiology ◽  
1984 ◽  
Vol 151 (1) ◽  
pp. 127-133 ◽  
Author(s):  
L E Crooks ◽  
M Arakawa ◽  
J Hoenninger ◽  
B McCarten ◽  
J Watts ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Field ◽  
Magnetic Resonance ◽  
Field Strength ◽  
Magnetic Field Strength ◽  
Resonance Imaging

MRI Susceptibility Artefacts Related to Scaphoid Screws: the Effect of Screw Type, Screw Orientation and Imaging Parameters

2002 ◽  
Vol 27 (2) ◽  
pp. 165-170 ◽  
Author(s):  
M. GANAPATHI ◽  
G. JOSEPH ◽  
R. SAVAGE ◽  
A. R. JONES ◽  
B. TIMMS ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Field ◽  
Titanium Alloy ◽  
Magnetic Resonance ◽  
Main Magnetic Field ◽  
Resonance Imaging ◽  
Metal Implants ◽  
Imaging Parameters ◽  
Susceptibility Artefact

Metal implants produce susceptibility artefacts in magnetic resonance imaging. We have explored the effects of scaphoid screw characteristics and orientation on MR susceptibility artefact. Titanium alloy, smallness and longitudinal alignment with the z-axis of the main magnetic field reduce the size of the susceptibility artefact.

Triaxial Fiber Optic Magnetic Field Sensor for Magnetic Resonance Imaging

2017 ◽  
Vol 35 (18) ◽  
pp. 3924-3933 ◽  
Author(s):  
Massimo L. Filograno ◽  
Marco Pisco ◽  
Angelo Catalano ◽  
Ernesto Forte ◽  
Marco Aiello ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Field ◽  
Magnetic Resonance ◽  
Fiber Optic ◽  
Magnetic Field Sensor ◽  
Resonance Imaging ◽  
Field Sensor

Magnetic resonance imaging without field cycling at less than earth's magnetic field

2015 ◽  
Vol 106 (10) ◽  
pp. 103702 ◽  
Author(s):  
Seong-Joo Lee ◽  
Jeong Hyun Shim ◽  
Kiwoong Kim ◽  
Kwon Kyu Yu ◽  
Seong-min Hwang
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Field ◽  
Magnetic Resonance ◽  
Resonance Imaging ◽  
Earth’S Magnetic Field ◽  
Earth's Magnetic Field ◽  
Field Cycling
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