Low-noise magnetic resonance imaging using low harmonic pulse sequences
AssigneeGeneral Electric Company
InventorsChristopher Judson Hardy, Graeme Colin McKinnon
Life of this patent
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Abstract
Systems and method for magnetic resonance imaging are disclosed which utilize sinusoidal gradient waveforms to drive gradient coils in an MRI system. The sinusoidal gradient waveforms may be applied on all two or more (e.g. three) gradient axes to produce a relatively pure acoustic tone. In certain embodiments, gradient directions may be spiraled in three-dimensions to generate a radial pin-cushion k-space trajectory
Claims21
A method for driving gradient coils of a magnetic resonance imaging system, comprising:
- driving at least a first gradient coil associated with a first gradient direction using a first sinusoidal gradient waveform and a second gradient coil associated with a second gradient direction using a second sinusoidal gradient waveform;
- generating RF pulses at one or more crossover events when the first sinusoidal gradient waveform and the second sinusoidal gradient waveform cross their respective gradient zero lines;
- acquiring a respective readout signal after each RF pulse;
- and
- generating an image using the acquired readout signals.
One or more tangible, non-transitory machine-readable media encoding processor-executable routines, wherein the routines, when executed by a processor cause acts to be performed comprising:
- driving at least a first gradient coil associated with a first gradient direction using a first sinusoidal gradient waveform and a second gradient coil associated with a second gradient direction using a second sinusoidal gradient waveform;
- generating RF pulses at one or more crossover events when the first sinusoidal gradient waveform and the second sinusoidal gradient waveform cross their respective gradient zero lines;
- acquiring a respective readout signal after each RF pulse;
- and
- generating an image using the acquired readout signals.
A magnetic resonance imaging (MRI) system, comprising:
- a primary field magnet;
- a plurality of gradient field coils;
- a radiofrequency (RF) transmit coil;
- an array of receiving coils;
- and
- control circuitry coupled to the gradient field coils, to the RF transmit coil, and to the array of receiving coils, wherein the control circuitry is configured to:
- drive at least a first gradient coil associated with a first gradient direction using a first sinusoidal gradient waveform and a second gradient coil associated with a second gradient direction using a second sinusoidal gradient waveform;
- generate RF pulses at one or more crossover events when the first sinusoidal gradient waveform and the second sinusoidal gradient waveform cross their respective gradient zero lines;
- acquire a respective readout signal after each RF pulse;
- and
- generate an image using the acquired readout signals.
Dependencies are inferred from the claim text.