Patent US4984573A successfully refreshed from Google Patents.
US4984573A
Expired / Lapsed
US
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Method of electron spin resonance enhanced magnetic resonance imaging
Assignee: GE Healthcare AS
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Filing: 1988-06-22
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Granted: 1991-01-15
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Expires: 2008-06-22
Abstract
Abstract A method of generating a magnetic resonance image of a sample comprising introducing into the sample a contrast medium comprising a paramagnetic material having an electron spin resonance transition having a linewidth of 1 Gauss or less; exposing the sample to a first radiation of a frequency selected to excite nuclear spin transitions in selective nuclei in the sample and exposing the sample to a second radiation of a frequency which excites electron spin transitions coupled to nuclear spin transitions of at least some nuclei, the second radiation being of a frequency selected to excite an electron spin resonance transition of the paramagnetic material; detecting free induction decay signals from the sample; and generating therefrom a magnetic resonance image of the sample.
Inventors
- 👤 Ib Leunbach
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 12:36
CPC Classifications
G; G01; G01R; G01R33/00; G01R33/20; G01R33/44; G01R33/48; G01R33/54; G01R33/56; G01R33/5601; A; A61; A61K; A61K49/00; A61K49/06; A61K49/20; G01R33/28; G01R33/282; G01R33/62; Y; Y10; Y10T; Y10T436/00; Y10T436/24
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
122 words
A method of generating a magnetic resonance image of a sample, said method comprising: introducing into said sample a contrast comprising a paramagnetic material having an electron spin resonance transition having a linewidth of 1 Gauss or less; exposing said sample to a first radiation of a frequency selected to excite nuclear spin transitions in selective nuclei in said sample and exposing said sample to a second radiation of a frequency which excites spin transitions coupled to nuclear spin transitions of at least some nuclei, said second radiation being of a frequency selected to excite said electron spin resonance transition of said paramagnetic material; detecting free induction decay signals from said sample; and generating therefrom a magnetic resonance image of said sample.
Claim 2
Independent Claim
122 words
A method of generating a magnetic resonance image of a sample, said method comprising: introducing into said sample a contrast comprising a paramagnetic material having an electron spin resonance transition having a linewidth of 1 Gauss or less; exposing said sample to a first radiation of a frequency selected to excite nuclear spin transitions in selective nuclei in said sample and exposing said sample to a second radiation of a frequency which excites spin transitions coupled to nuclear spin transitions of at least some nuclei, said second radiation being of a frequency selected to excite said electron spin resonance transition of said paramagnetic material; detecting free induction decay signals from said sample; and generating therefrom a magnetic resonance image of said sample.
Claim 3
Dependent Claim
51 words
A method as claimed in claim 1 wherein said sample is exposed to a series of pulse sequences of said first radiation and said image is generated using only said free induction decay signals detected during those of said pulse sequences in which said sample is exposed to said second radiation.
Claim 4
Dependent Claim
54 words
A method as claimed in claim 1 wherein said sample is exposed to a series of pulse sequences of said first radiation and during said pulse sequences said sample is maintained in a magnetic field generated by a primary magnet means arranged to generate a field of from 0.5 Gauss to about 0.02 Tesla.
Claim 5
Dependent Claim
48 words
A method as claimed in claim 1 wherein said contrast medium comprises a paramagnetic material having an electron spin resonance transition with a line width of 100 mG or less and wherein said second radiation comprises radiation of a frequency selected to excite said electron spin resonance transition.
Claim 6
Dependent Claim
20 words
A method as claimed in claim 1 wherein said electron spin resonance transition is in a singlet, duplet or triplet.
Claim 7
Dependent Claim
22 words
A method as claimed in claim 1 wherein said contrast medium comprises a physiologically tolerable nitroxide stable free radical other than 4-hydroxy-2,2,6,2-tetramethylpiperidine-1-oxyl.
Claim 8
Dependent Claim
71 words
A method as claimed in claim 6 wherein said nitroxide stable free radical is a cyclic nitroxide wherein the NO moiety occurs in a 5 to 7-membered saturated or ethylenically unsaturated ring with the adjacent ring positions being occupied by doubly substituted carbon atoms, and with one of the remaining ring positions being coupled by a carbon, oxygen or sulphur atom and any remaining ring positions being occupied by carbon atoms.
Claim 9
Dependent Claim
37 words
A method as claimed in claim 1 wherein said paramagnetic material is introduced into said sample to produce a concentration of one 1μM to 10mM in that portion of said sample of which said image is generated.
Claim 10
Dependent Claim
34 words
A method as claimed in claim 8 wherein said paramagnetic material is introduced to produce a concentration of from 3mM to 9mM in that portion of said sample of which said image is generated.
Claim 11
Dependent Claim
21 words
A method as claimed in claim 1 wherein said free induction decay signals are detected enhanced intensity proton magnetic resonance signals.
Claim 12
Dependent Claim
54 words
A method as claimed in claim 1 wherein said paramagnetic material has at least two electron spin resonance transitions having linewidths of less than 1 Gauss and wherein said second radiation used is a radiation having a frequency distribution selected to excite at least two said electron spin resonance transitions of said paramagnetic material.
Claim 13
Independent Claim
129 words
A method of magnetic resonance imaging of the human or animal body, said method comprising: introducing into said body a contrast medium comprising a physiologically tolerable paramagnetic material having an electron spin resonance transition having a linewidth of 1 Gauss or less; exposing said body to a first radiation of a frequency selected to a excite nuclear spin transitions in selected nuclei in said body and exposing said body to a second radiation of a frequency which excites electron spin transitions coupled to nuclear spin transitions of at least some of said nuclei, said second radiation being of a frequency selected to excite said electron spin resonance transition of said paramagnetic material; detecting free induction decay signals from said body; and generating a magnetic resonance image of said body.
Claim 14
Independent Claim
129 words
A method of magnetic resonance imaging of the human or animal body, said method comprising: introducing into said body a contrast medium comprising a physiologically tolerable paramagnetic material having an electron spin resonance transition having a linewidth of 1 Gauss or less; exposing said body to a first radiation of a frequency selected to a excite nuclear spin transitions in selected nuclei in said body and exposing said body to a second radiation of a frequency which excites electron spin transitions coupled to nuclear spin transitions of at least some of said nuclei, said second radiation being of a frequency selected to excite said electron spin resonance transition of said paramagnetic material; detecting free induction decay signals from said body; and generating a magnetic resonance image of said body.
Claim 15
Dependent Claim
28 words
A method as claimed in claim 12, wherein said a physiologically tolerable paramagnetic material has an electron spin resonance transition with a linewidth of 100 mG or less.
Claim 16
Dependent Claim
22 words
A method as claimed in claim 12, wherein said contrast medium comprises a physiologically tolerable nitroxide stable free radical other than 4-hydroxy-2,2,6,6-tetramethylpiperidine-2-oxyl.
Claim 17
Dependent Claim
73 words
A method as claimed in claim 14 wherein the NO moiety of said physiologically tolerable cyclic nitroxide stable free radical occurs in a 5 to 7-membered saturated or ethylenically unsaturated ring with the ring positions adjacent to it being occupied by doubly substituted carbon atoms and with one of the remaining ring positions being occupied by a carbon, oxygen or sulphur atom and the other remaining ring positions being occupied by carbon atoms.
Claim 18
Dependent Claim
20 words
A method as claimed in claim 12 wherein said electron spin resonance transition is in a singlet, duplet or triplet.
Claim 19
Dependent Claim
54 words
A method as claimed in claim 12 wherein said paramagnetic material has at least two electron spin resonance transitions having linewidths of less than 1 Gauss and wherein said second radiation used is a radiation having a frequency distribution selected to excite at least two said electron spin resonance transitions of said paramagnetic material.
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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) | 1994-01-14 | 1994-07-16 | 1995-01-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-01-14 | 1998-07-16 | 1999-01-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-01-14 | 2002-07-16 | 2003-01-15 | $7700.00 | Window Closed / Lapsed |