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Updated: Jun 17, 2026
09:14
Cardiac Magnetic Resonance Imaging at 7 Tesla
Published on: January 6, 2019
Eddy current effects on a clinical 7T-68 cm bore scanner
Nils Kickler1, Wietske van der Zwaag, Ralf Mekle
1Laboratory for Functional and Metabolic Imaging, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland. NilsKickler@googlemail.com
Magma (New York, N.Y.)
|December 17, 2009
Summary
Eddy currents in head-only MRI systems are challenging. This study characterized eddy current effects on a 7T system, showing compensation comparable to whole-body systems despite faster gradients.
Area of Science:
- Magnetic Resonance Imaging (MRI)
- Biomedical Engineering
- Physics
Background:
- Eddy currents from switching magnetic field gradients cause distortions in MRI.
- Minimizing eddy currents is critical in head-only MRI systems due to coil proximity to conductive structures.
Purpose of the Study:
- To characterize eddy current behavior on a new 7 Tesla (T), 68 cm bore, head-only MRI magnet.
- To assess the effectiveness of eddy current compensation strategies in this specific system.
Main Methods:
- Characterization of eddy current effects on a 7T head-only MRI system.
- Comparison of residual eddy current effects with established whole-body MRI systems.
Main Results:
- Eddy current compensation on the 7T head-only system achieved residual effects comparable to 3T and 4.7T whole-body systems.
- This was accomplished using significantly faster gradient slew rates (two to three fold increase).
Conclusions:
- Effective eddy current compensation is achievable on high-field, head-only MRI systems.
- The results suggest that advanced head-only MRI systems can maintain image quality despite demanding gradient performance.
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