Hardware Considerations in Ultra High Field MRI
Ultra high field MRI systems present a number of unique challenges to the system designer and integrator beyond simply scaling up the performance of a lower field system. The primary areas of concern are the magnet, gradient coils and drivers, and RF coils and coil interface. The art of system integration lies in identifying sufficiently clear performance targets for each of the subsystems and ensuring that those targets are met in a way that preserves the overall performance of the system. The following discussion identifies for each of these areas the key performance requirements that are changed at higher field strengths, methods to address those requirements, and how those methods affect the rest of the system. As this is an area of ongoing research and development, many of the specific solutions presented here are likely to be superseded in the future, but the general approach to the problem should remain valid. While a complete description of every aspect of system design and integration of UHFMRI systems is beyond the scope of this chapter, the following is intended to provide practical guidance in addressing the more common problems in siting or operating a UHFMRI system.
KeywordsHigh Field Strength Gradient Coil Load Impedance Coil Element Transmitter Coil
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