Patent EP0161366A2 successfully refreshed from Google Patents.
EP0161366A2
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EP
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Nuclear magnetic resonance methods and apparatus
Assignee: Philips Design Ltd
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Filing: 1984-11-21
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Granted: —
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Expires: 2004-11-21
Abstract
Abstract An NMR imaging method and apparatus wherein spatial encoding of spins is effected by applying a radio frequency field (B2) having a gradient, thereby avoiding the eddy current problems which can arise with d.c. gradient magnetic pulses conventionally used for spatially encoding spins.
Inventors
- 👤 Ian Robert Young
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-06 08:34
CPC Classifications
G; G01; G01R; G01R33/00; G01R33/20; G01R33/44; G01R33/48; G01R33/4818; G01R33/482; G01R33/483; G01R33/4831; G01R33/54; G01R33/56; G01R33/565; G01R33/56518
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
61 words
A method of investigating the spatial distribution of a quantity in a selected region of a body using NMR techniques including the step of spatial encoding of nuclear spins in said selected region characterised in that said spatial encoding is effected at least partly by applying to said region a radio frequency magnetic field having a gradient (B2) across said region.
Claim 2
Independent Claim
61 words
A method of investigating the spatial distribution of a quantity in a selected region of a body using NMR techniques including the step of spatial encoding of nuclear spins in said selected region characterised in that said spatial encoding is effected at least partly by applying to said region a radio frequency magnetic field having a gradient (B2) across said region.
Claim 3
Dependent Claim
32 words
A method according to Claim 1 wherein nuclear magnetic spins are first excited in said region and subsequently said spins are spatially encoded by applying said radio frequency field having a gradient.
Claim 4
Dependent Claim
50 words
A method according to Claim 1 or Claim 2 wherein said radio frequency field (B2) is applied during application to said body of a further magnetic field gradient (-Gz) such that said radio frequency field is effective to encode nuclear magnetic spins preferentially in a selected region of said body.
Claim 5
Dependent Claim
61 words
A method according to Claim 3 wherein said further magnetic field gradient (-Gz) also serves to rephase spins produced in said region by previous application to said body of a magnetic field gradient (Gz) in the reverse direction to said further gradient together with a radio frequency magnetic field (B1) so as to excite nuclear magnetic spins preferentially in said region.
Claim 6
Independent Claim
42 words
A method according to any one of the preceding claims wherein more than one said radio frequency field having a gradient across said region is applied to encode said spins, each said radio frequency field having a gradient in a different direction.
Claim 7
Independent Claim
76 words
A method according to any one of the preceding claims comprising the steps of: (1) exciting spatially encoded nuclear magnetic spins in said selected region (B1, B2, Gz, -Gz); (2) detecting signals representative of said spins (Figure 2c); and (3) processing said detected spins to retrieve data; steps (1) and (2) being repeated a number of times with a different value for the gradient of the or one said radio frequency magnetic field (B1) each time.
Claim 8
Independent Claim
97 words
An apparatus for investigating the spatial distribution of a quantity in a selected region of a body using NMR techniques characterised by means (1,7,9,11,17,19,21,25,27,29) arranged to excite nuclear magnetic spins in a selected region of a body; means (9,19,27,29) arranged to apply to said region a radio frequency magnetic field having a gradient across said region, thereby to spatially encode the spins occurring in said region; detector means (9,29,35,37) arranged to produce signals representative of the spins occurring in said region; and processing means (29) arranged to retrieve data from the signals detected by said detector means.
Claim 9
Independent Claim
97 words
An apparatus for investigating the spatial distribution of a quantity in a selected region of a body using NMR techniques characterised by means (1,7,9,11,17,19,21,25,27,29) arranged to excite nuclear magnetic spins in a selected region of a body; means (9,19,27,29) arranged to apply to said region a radio frequency magnetic field having a gradient across said region, thereby to spatially encode the spins occurring in said region; detector means (9,29,35,37) arranged to produce signals representative of the spins occurring in said region; and processing means (29) arranged to retrieve data from the signals detected by said detector means.
Claim 10
Dependent Claim
54 words
An apparatus according to Claim 7 wherein said means arranged to apply to said region a radio frequency magnetic field comprises two coils (9) positioned on opposite sides of said region in the direction of said gradient, and means (19,27,29) for applying radio frequency drive signals to said coils of opposite radio frequency phase.
References Cited (Backward Citations)
No citation records indexed.
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