A programmable eddy-current compensation system for MRI and localized spectroscopy
M E Fry1, S Pittard, I R Summers
1Department of Physics, University of Exeter, United Kingdom.
Journal of Magnetic Resonance Imaging : JMRI
|March 1, 1997
Summary
A new programmable preemphasis system compensates for eddy-currents in MRI gradient sets. This adaptable system offers rapid parameter changes and easy retrofitting to existing magnetic resonance imaging equipment.
Area of Science:
- Medical Physics
- Magnetic Resonance Imaging
Background:
- Eddy currents in magnetic resonance imaging (MRI) gradient coils can degrade image quality.
- Active screening is used in some systems to mitigate eddy currents, but limitations remain.
Purpose of the Study:
- To develop and present a programmable preemphasis system for eddy-current compensation.
- To enable rapid adjustment of preemphasis parameters for interchangeable gradient sets.
- To facilitate easy integration of the system into existing MRI hardware.
Main Methods:
- Development of a programmable preemphasis system.
- Implementation of nonvolatile storage for preemphasis parameters.
- Design for rapid parameter modification and system retrofitting.
Main Results:
- Successful development of a programmable preemphasis system for eddy-current compensation.
- Demonstration of nonvolatile parameter storage and rapid adjustability.
- Validation of the system's applicability to gradient sets with and without active screening.
Conclusions:
- The developed programmable preemphasis system effectively compensates for eddy currents in MRI gradient sets.
- The system's adaptability and ease of retrofitting make it a valuable enhancement for existing MRI systems.
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