GB2294771A - Improvements in or relating to nuclear magnetic resonance (nmr)imaging - Google Patents

Improvements in or relating to nuclear magnetic resonance (nmr)imaging

Info

Publication number
GB2294771A
GB2294771A GB9524964A GB9524964A GB2294771A GB 2294771 A GB2294771 A GB 2294771A GB 9524964 A GB9524964 A GB 9524964A GB 9524964 A GB9524964 A GB 9524964A GB 2294771 A GB2294771 A GB 2294771A
Authority
GB
United Kingdom
Prior art keywords
pulse
gradient
imaging
echo
noise ratio
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
GB9524964A
Other versions
GB2294771B (en
GB9524964D0 (en
Inventor
Peter John Mcdonald
Timothy Birkett Benson
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
BTG International Ltd
Original Assignee
British Technology Group Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by British Technology Group Ltd filed Critical British Technology Group Ltd
Publication of GB9524964D0 publication Critical patent/GB9524964D0/en
Publication of GB2294771A publication Critical patent/GB2294771A/en
Application granted granted Critical
Publication of GB2294771B publication Critical patent/GB2294771B/en
Anticipated expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R33/00—Arrangements or instruments for measuring magnetic variables
    • G01R33/20—Arrangements or instruments for measuring magnetic variables involving magnetic resonance
    • G01R33/44—Arrangements or instruments for measuring magnetic variables involving magnetic resonance using nuclear magnetic resonance [NMR]
    • G01R33/48—NMR imaging systems
    • G01R33/4816—NMR imaging of samples with ultrashort relaxation times such as solid samples, e.g. MRI using ultrashort TE [UTE], single point imaging, constant time imaging

Abstract

The invention describes an improved NMR imaging technique having particular application in imaging of solid objects using gradient echo techniques. By applying a so called 90 DEG rf pulse substantially at zero gradient crossing it is possible to obtain frequency encoded information about an object being imaged, using a so called gradient echo technique. However, profile degradation occurs as a result of the very large magnetic fields which are used which spoil the rf pulse. By shortening the length of pulses 90 DEG it has been possible to improve gradient echo imaging. However, this has resulted in the reduction in the signal-to-noise ratio of the echo following each pulse. The present invention overcomes this problem by providing a rapidly oscillating magnetic field gradient and applying a radio frequency pulse away from a zero gradient crossing and by substantially phase rotating the resultant profile. The result is the surprising effect that information is preserved, the pulse bandwidth remains constant and the signal-to-noise ratio is superior to that in existing systems. <IMAGE>
GB9524964A 1993-07-30 1994-07-29 Improvements in or relating to nuclear magnetic resonance (nmr)imaging Expired - Fee Related GB2294771B (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
GB939315876A GB9315876D0 (en) 1993-07-30 1993-07-30 Improvements in or relating to nuclear magnetic resonance (nmr) imaging
PCT/GB1994/001640 WO1995004288A1 (en) 1993-07-30 1994-07-29 Improvements in or relating to nuclear magnetic resonance (nmr) imaging

Publications (3)

Publication Number Publication Date
GB9524964D0 GB9524964D0 (en) 1996-02-21
GB2294771A true GB2294771A (en) 1996-05-08
GB2294771B GB2294771B (en) 1997-11-19

Family

ID=10739752

Family Applications (2)

Application Number Title Priority Date Filing Date
GB939315876A Pending GB9315876D0 (en) 1993-07-30 1993-07-30 Improvements in or relating to nuclear magnetic resonance (nmr) imaging
GB9524964A Expired - Fee Related GB2294771B (en) 1993-07-30 1994-07-29 Improvements in or relating to nuclear magnetic resonance (nmr)imaging

Family Applications Before (1)

Application Number Title Priority Date Filing Date
GB939315876A Pending GB9315876D0 (en) 1993-07-30 1993-07-30 Improvements in or relating to nuclear magnetic resonance (nmr) imaging

Country Status (7)

Country Link
US (1) US5623206A (en)
EP (1) EP0804629A1 (en)
JP (1) JPH09502518A (en)
FI (1) FI960405A (en)
GB (2) GB9315876D0 (en)
IL (1) IL110477A (en)
WO (1) WO1995004288A1 (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2337125A (en) * 1998-04-03 1999-11-10 Univ Ludwigs Albert Acoustic noise reduction in MR tomography

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1997004329A1 (en) * 1995-07-20 1997-02-06 Philips Electronics N.V. Method and device for imaging a curved portion of a body by means of magnetic resonance
US7750633B2 (en) * 2004-07-22 2010-07-06 The Regents Of The University Of California Low field magnetic resonance imaging

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0259998A2 (en) * 1986-09-04 1988-03-16 National Research Development Corporation Methods of imaging solids by NMR techniques
WO1991000529A1 (en) * 1989-06-23 1991-01-10 National Research Development Corporation Nuclear magnetic resonance imaging methods
WO1993014416A1 (en) * 1992-01-13 1993-07-22 British Technology Group Ltd Method of and apparatus for obtaining spatial nmr information

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0076054B1 (en) * 1981-09-21 1986-06-04 Peter Mansfield Nuclear magnetic resonance methods
GB8915090D0 (en) * 1989-06-30 1989-08-23 Cottrell Stephen P Nuclear magnetic resonance imaging methods
GB9217718D0 (en) * 1992-08-20 1992-09-30 British Tech Group Method of and apparatus for nmr testing

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0259998A2 (en) * 1986-09-04 1988-03-16 National Research Development Corporation Methods of imaging solids by NMR techniques
WO1991000529A1 (en) * 1989-06-23 1991-01-10 National Research Development Corporation Nuclear magnetic resonance imaging methods
WO1993014416A1 (en) * 1992-01-13 1993-07-22 British Technology Group Ltd Method of and apparatus for obtaining spatial nmr information

Non-Patent Citations (5)

* Cited by examiner, † Cited by third party
Title
J. Mag. Res. 76 pp 543-544 *
J. Mag. Res. 82 pp 529-538 *
J. Mag. Res. 87 pp 554-566 *
Meas. Sci. and Technology 1 pp 1153-1158 *
Phys. in Med. and Biol. 35 pp 1153-1158 *

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2337125A (en) * 1998-04-03 1999-11-10 Univ Ludwigs Albert Acoustic noise reduction in MR tomography
GB2337125B (en) * 1998-04-03 2002-11-13 Univ Ludwigs Albert Magnetic resonance imaging method for noise-free investigations,in particular of brain activation

Also Published As

Publication number Publication date
WO1995004288A1 (en) 1995-02-09
IL110477A0 (en) 1994-10-21
FI960405A0 (en) 1996-01-29
US5623206A (en) 1997-04-22
FI960405A (en) 1996-01-29
GB2294771B (en) 1997-11-19
JPH09502518A (en) 1997-03-11
GB9524964D0 (en) 1996-02-21
IL110477A (en) 1997-02-18
GB9315876D0 (en) 1993-09-15
EP0804629A1 (en) 1997-11-05

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Legal Events

Date Code Title Description
PCNP Patent ceased through non-payment of renewal fee

Effective date: 20010729