Patent US4458203A successfully refreshed from Google Patents.
US4458203A
Expired / Lapsed
US
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Nuclear magnetic resonance imaging
Assignee: Philips Design Ltd
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Filing: 1981-12-01
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Granted: 1984-07-03
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Expires: 2001-12-01
Abstract
Abstract A method of imaging a body by nuclear magnetic resonance wherein volume scanning of a region of the body is achieved by scanning a first planar slice of the region and at least one further slice of the region in the relaxation time for the scan of the first slice.
Inventors
- 👤 Ian R. Young
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 17:29
CPC Classifications
G; G01; G01R; G01R33/00; G01R33/20; G01R33/44; G01R33/48; G01R33/483; G01R33/4833; G01R33/4835
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
102 words
A method of imaging a body by nuclear magnetic resonance using data obtained by T 1 experiments wherein volume scanning of a region of the body is achieved by scanning for T 1 data in each of a plurality of planar parallel slices of said region by applying in turn a series of π/2 radio frequency pulses, each with magnetic field gradients for selecting a different one of said slices, between successive ones of a sequence of π radio frequency pulses, the scan of at least one slice occurring in the relaxation time for the scan of at least one other slice.
Claim 2
Independent Claim
102 words
A method of imaging a body by nuclear magnetic resonance using data obtained by T 1 experiments wherein volume scanning of a region of the body is achieved by scanning for T 1 data in each of a plurality of planar parallel slices of said region by applying in turn a series of π/2 radio frequency pulses, each with magnetic field gradients for selecting a different one of said slices, between successive ones of a sequence of π radio frequency pulses, the scan of at least one slice occurring in the relaxation time for the scan of at least one other slice.
Claim 3
Dependent Claim
19 words
A method according to claim 1 wherein slice selection is effected by controlling the frequency of the (π/2) pulses.
Claim 4
Dependent Claim
36 words
A method according to claim 1 wherein the slice selection field gradients include a phase correction magnetic field gradient pulse whose size is varied so as to resolve a scanned slice into a plurality of subslices.
Claim 5
Independent Claim
120 words
A method of imaging a body by nuclear magnetic resonance using data obtained by T 1 experiments, said method comprising the steps of: (a) producing a sequence of π radio frequency pulses; (b) applying in turn a series of 90 /2 radio frequency pulses, each with a magnetic field gradient for selecting a different slice of the body; (c) scanning for T 1 data in each of a plurality of planar parallel slices of said region to achieve volume scanning of a region, said π/2 frequency pulses taking place between successive ones of said sequence of radio frequency pulses, and (d) wherein said scanning of at least one slice occurs during the relaxation time for the scan of another slice.
Claim 6
Independent Claim
120 words
A method of imaging a body by nuclear magnetic resonance using data obtained by T 1 experiments, said method comprising the steps of: (a) producing a sequence of π radio frequency pulses; (b) applying in turn a series of 90 /2 radio frequency pulses, each with a magnetic field gradient for selecting a different slice of the body; (c) scanning for T 1 data in each of a plurality of planar parallel slices of said region to achieve volume scanning of a region, said π/2 frequency pulses taking place between successive ones of said sequence of radio frequency pulses, and (d) wherein said scanning of at least one slice occurs during the relaxation time for the scan of another slice.
Claim 7
Independent Claim
138 words
A system for imaging a body by nuclear magnetic resonance using data obtained by T 1 experiments, said system comprising: (a) apparatus and circuitry for producing a series of π radio frequency pulses; (b) second apparatus and circuitry for applying in turn a series of π/2 radio frequency pulses, each with a magnetic field gradient for selecting a different slice of the body, said π/2 frequency pulses being timed to take place between successive ones of said sequence of π radio frequency pulses, said second apparatus and circuitry comprising means for scanning for T 1 data in each of a plurality of planar parallel slices of said region to achieve volume scanning of a region, and (c) timing means for effecting said scanning of at least one slice during the relaxation time for the scan of another slice.
Claim 8
Independent Claim
138 words
A system for imaging a body by nuclear magnetic resonance using data obtained by T 1 experiments, said system comprising: (a) apparatus and circuitry for producing a series of π radio frequency pulses; (b) second apparatus and circuitry for applying in turn a series of π/2 radio frequency pulses, each with a magnetic field gradient for selecting a different slice of the body, said π/2 frequency pulses being timed to take place between successive ones of said sequence of π radio frequency pulses, said second apparatus and circuitry comprising means for scanning for T 1 data in each of a plurality of planar parallel slices of said region to achieve volume scanning of a region, and (c) timing means for effecting said scanning of at least one slice during the relaxation time for the scan of another slice.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-07-03 | 1988-01-02 | 1988-07-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-07-03 | 1992-01-02 | 1992-07-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-07-03 | 1996-01-02 | 1996-07-03 | $7700.00 | Window Closed / Lapsed |