|SOFTWARE CONTROLLED SHIM PULSES CORRECT FOR ARTIFACTS INDUCED BY HARDWARE|
|(a) A liquid sample in an 8 by 8 array of square wells spanning 20 by 20 mm in the x,y plane. Simulated images of the sample using (b) standard MRI methods and (c) positional encoding with the Berkeley Lab shim pulse method. The size of each square well in (b) corresponds to the strength of the gradient at each particular point in space.|
- High resolution NMR and MRI for industrial, pharmaceutical, and biomedical applications
- Achieves high resolution with inexpensive, smaller, and simplified magnets
- Anticipated to reduce the required homogeneity over the sample volume by an order of magnitude
- Enables the use of larger sample volumes resulting in larger signals and greater sensitivity
- Allows several samples to be placed inside the same magnet for high throughput NMR/MRI
- Enables ex-situ spectroscopy without the requirement for field matching
Alexander Pines and colleagues at Berkeley Labs have made it possible to obtain high resolution NMR and MRI without expensive and immobile superconducting magnets. The method uses advanced software control of the RF and gradient pulses to reshape the magnetic field produced by auxiliary coils, effectively substituting software for the bulky hardware used for conventional magnet shimming. The invention is anticipated to reduce the required homogeneity over the sample volume by an order of magnitude.
The Berkeley Lab invention reduces the linewidth of the NMR spectrum and provides non-distorted images using simpler, smaller, and less expensive gradient coils. It captures valuable structural and dynamic information that enables accurate material identification and product control. The shim pulse invention acquires spectra more rapidly and accommodates larger sample volumes than conventional magnet systems. Multiple samples can also be examined simultaneously.
Simulated example of the linewidth narrowing that can be achieved using the Berkeley Lab shim pulse method for a sample in a magnetic field inhomogeneity.Shim pulse with amplitude (AM) and frequency (FM) modulation of the RF field together with modulated gradient fields (Gx,Gy,Gz).
- Issued Patent # 7,439,738. Available for licensing or collaborative research.
REFERENCE NUMBER: IB-2026
SEE THESE OTHER BERKELEY LAB TECHNOLOGIES IN THIS FIELD:
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