US7187169B2
Expired / Lapsed
US
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NMR and MRI apparatus and method
Assignee: University of California
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Filing: 2004-11-03
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Granted: 2007-03-06
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Expires: 2024-11-03
Abstract
Abstract Nuclear magnetic resonance (NMR) signals are detected in microtesla fields. Prepolarization in millitesla fields is followed by detection with an untuned dc superconducting quantum interference device (SQUID) magnetometer. Because the sensitivity of the SQUID is frequency independent, both signal-to-noise ratio (SNR) and spectral resolution are enhanced by detecting the NMR signal in extremely low magnetic fields, where the NMR lines become very narrow even for grossly inhomogeneous measurement fields. Additional signal to noise benefits are obtained by use of a low noise polarization coil, comprising litz wire or superconducting materials. MRI in ultralow magnetic field is based on the NMR at ultralow fields. Gradient magnetic fields are applied, and images are constructed from the detected NMR signals.
Inventors
- 👤 John Clarke
- 👤 Nathan Kelso
- 👤 SeungKyun Lee
- 👤 Michael Moessle
- 👤 Whittier Myers
- 👤 Robert McDermott
- 👤 Bernard ten Haken
- 👤 Alexander Pines
- 👤 Andreas Trabesinger
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 13:05
CPC Classifications
G; G01; G01R; G01R33/00; G01R33/20; G01R33/28; G01R33/32; G01R33/323; G01R33/326
Claims Analysis
Total Claims: 27
Claim 1
Independent Claim
53 words
A method for performing nuclear magnetic resonance (NMR) of a sample, comprising: polarizing nuclear spins in the sample in a magnetic field; suppressing Nyquist noise consequent to polarization; and, detecting nuclear magnetic resonance (NMR) signals from the sample in a Nyquist noise-suppressed microtesla magnetic field with a superconducting quantum interference device (SQUID) magnetometer.
Claim 2
Independent Claim
53 words
A method for performing nuclear magnetic resonance (NMR) of a sample, comprising: polarizing nuclear spins in the sample in a magnetic field; suppressing Nyquist noise consequent to polarization; and, detecting nuclear magnetic resonance (NMR) signals from the sample in a Nyquist noise-suppressed microtesla magnetic field with a superconducting quantum interference device (SQUID) magnetometer.
Claim 3
Dependent Claim
24 words
The method of claim 1 wherein the suppressing step comprises providing a low noise polarizing coil which is then used in the polarizing step.
Claim 4
Dependent Claim
20 words
The method of claim 2 wherein the suppressing step comprises providing a low noise polarizing coil which comprises litz wire.
Claim 5
Dependent Claim
20 words
The method of claim 2 wherein the suppressing step comprises providing a low noise polarizing coil which comprises superconducting wire.
Claim 6
Dependent Claim
24 words
The method of claim 2 wherein the suppressing step comprises providing a low noise polarizing coil which comprises a means for Nyquist noise reduction.
Claim 7
Dependent Claim
15 words
The method of claim 1 wherein the polarizing magnetic field is greater than 10 mT.
Claim 8
Dependent Claim
15 words
The method of claim 6 wherein the polarizing magnetic field is greater than 100 mT.
Claim 9
Dependent Claim
15 words
The method of claim 7 wherein the polarizing magnetic field is greater than 250 mT.
Claim 10
Dependent Claim
15 words
The method of claim 8 wherein the polarizing magnetic field is greater than 500 mT.
Claim 11
Dependent Claim
26 words
The method of claim 1 wherein the detecting step comprises use of an untuned low critical temperature (T c ) superconducting quantum interference device (SQUID) magnetometer.
Claim 12
Dependent Claim
27 words
The method of claim 1 further comprising the step of performing magnetic resonance imaging (MRI) of the sample by forming an image from the detected NMR signals.
Claim 13
Dependent Claim
15 words
The method of claim 11 further comprising applying encoding magnetic field gradients to the sample.
Claim 14
Dependent Claim
12 words
The method of claim 11 further comprising a step of performing magnetoencephalography.
Claim 15
Independent Claim
75 words
An apparatus for nuclear magnetic resonance (NMR) of a sample, comprising: polarization coils for providing a millitesla magnetic field for polarizing nuclear spins in a sample; a means for suppressing Nyquist noise; measurement coils for providing a microtesla magnetic field for detecting nuclear magnetic resonance (NMR) signals from the sample; and an untuned low critical temperature (T c ) superconducting quantum interference device (SQUID) magnetometer for detecting nuclear magnetic resonance (NMR) signals from the sample.
Claim 16
Independent Claim
75 words
An apparatus for nuclear magnetic resonance (NMR) of a sample, comprising: polarization coils for providing a millitesla magnetic field for polarizing nuclear spins in a sample; a means for suppressing Nyquist noise; measurement coils for providing a microtesla magnetic field for detecting nuclear magnetic resonance (NMR) signals from the sample; and an untuned low critical temperature (T c ) superconducting quantum interference device (SQUID) magnetometer for detecting nuclear magnetic resonance (NMR) signals from the sample.
Claim 17
Dependent Claim
18 words
The apparatus of claim 10 , wherein the means for suppressing Nyquist noise comprises low noise polarization coils.
Claim 18
Dependent Claim
14 words
The apparatus of claim 15 wherein the low noise polarizing coils comprise litz wire.
Claim 19
Dependent Claim
14 words
The apparatus of claim 15 wherein the low noise polarizing coils comprise superconducting wire.
Claim 20
Dependent Claim
18 words
The apparatus of claim 14 wherein the polarizing coil provides a magnetic field of greater than 10 mT.
Claim 21
Dependent Claim
18 words
The apparatus of claim 18 wherein the polarizing coil provides a magnetic field of greater than 100 mT.
Claim 22
Dependent Claim
18 words
The apparatus of claim 19 wherein the polarizing coil provides a magnetic field of greater than 250 mT.
Claim 23
Dependent Claim
18 words
The apparatus of claim 20 wherein the polarizing coil provides a magnetic field of greater than 500 mT.
Claim 24
Dependent Claim
14 words
The apparatus of claim 14 further comprising a means for cooling the polarizing coil.
Claim 25
Dependent Claim
26 words
The apparatus of claim 14 further comprising means to perform magnetic resonance imaging (MRI) of the sample by forming an image from the detected NMR signals.
Claim 26
Dependent Claim
15 words
The apparatus of claim 23 wherein the means to perform MRI comprises gradient field coils.
Claim 27
Dependent Claim
13 words
The apparatus of claim 23 further comprising a SQUID array for performing magnetoencephalography.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2010-03-05 | 2010-09-04 | 2011-03-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2014-03-05 | 2014-09-04 | 2015-03-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2018-03-05 | 2018-09-04 | 2019-03-06 | $7700.00 | Window Closed / Lapsed |