US5089784A
Expired / Lapsed
US
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Method for restricting region for magnetic resonance imaging
Assignee: GE Healthcare Japan Corp
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Filing: 1988-12-24
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Granted: 1992-02-18
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Expires: 2008-12-24
Abstract
Abstract The method for restricting a region for magnetic resonance imaging, in accordance with the present invention, comprising a step of measuring a spin-echo signal from an object by a pulse sequence of Fourier transformation technique; a step of measuring a spin-echo signal from an object by a pulse sequence comprising adding a selective 180°±x pulse and a selective 180°±y pulse following a 180° pulse in the pulse sequence of Fourier transform technique, the integral of gradient magnetic fields for selection thereof being 0; and a step of reconstructing an image from the addition or subtraction between the spin-echo signals measured by the two sequences.
Inventors
- 👤 Eiji Yoshitome
- 👤 Susumu Kosugi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 01:04
CPC Classifications
G; G01; G01R; G01R33/00; G01R33/20; G01R33/44; G01R33/48; G01R33/483; G01R33/4833; G01R33/54; G01R33/56
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
155 words
In a method of magnetic resonance imaging wherein a first spin echo signal of an object is obtained by applying a first RF pulse sequence comprising 90° and 180° pulses and at least one gradient magnetic field applied along one axis; the improvement comprising the steps of obtaining a second spin echo signal of said object by applying a second RF pulse sequence comprising said first RF pulse sequence and after the 180° pulse of said first RF pulse sequence a selective 180°±X pulse and a selective 180°±Y pulse, and an added pair of magnetic fields applied along said one axis with an integral therebetween of zero and applied during the selectively added RF pulses; selectively combining said first and second spin echo signals; and reconstructing an image of said object by utilizing a Fourier transform technique and the combined first and second spin echo signals, so that a restricted region of imaging is attained.
Claim 2
Dependent Claim
155 words
In a method of magnetic resonance imaging wherein a first spin echo signal of an object is obtained by applying a first RF pulse sequence comprising 90° and 180° pulses and at least one gradient magnetic field applied along one axis; the improvement comprising the steps of obtaining a second spin echo signal of said object by applying a second RF pulse sequence comprising said first RF pulse sequence and after the 180° pulse of said first RF pulse sequence a selective 180°±X pulse and a selective 180°±Y pulse, and an added pair of magnetic fields applied along said one axis with an integral therebetween of zero and applied during the selectively added RF pulses; selectively combining said first and second spin echo signals; and reconstructing an image of said object by utilizing a Fourier transform technique and the combined first and second spin echo signals, so that a restricted region of imaging is attained.
Claim 3
Dependent Claim
176 words
In a method of magnetic resonance imaging wherein a first spin echo signal of an object is obtained by applying a first RF pulse sequence comprising 90° and 180° pulses and at least one gradient magnetic field applied along one axis; the improvement comprising the steps of obtaining a second spin echo signal of said object by applying a second RF pulse sequence comprising said first RF pulse sequence and after the 180° pulse of said first RF pulse sequence a selective 180°±X pulse and a selective 180°±Y pulse, and an added pair of magnetic fields applied along said one axis with an integral therebetween of zero and applied during the selectively added RF pulses; reconstructing a first image of the object by utilizing a Fourier transform technique and said first spin echo signal; reconstructing a second image by utilizing a Fourier transform technique and said second spin echo signal; and projecting an image of the object by selectively combining said first image and said second image, so that a restricted region of imaging is attained.
Claim 4
Dependent Claim
176 words
In a method of magnetic resonance imaging wherein a first spin echo signal of an object is obtained by applying a first RF pulse sequence comprising 90° and 180° pulses and at least one gradient magnetic field applied along one axis; the improvement comprising the steps of obtaining a second spin echo signal of said object by applying a second RF pulse sequence comprising said first RF pulse sequence and after the 180° pulse of said first RF pulse sequence a selective 180°±X pulse and a selective 180°±Y pulse, and an added pair of magnetic fields applied along said one axis with an integral therebetween of zero and applied during the selectively added RF pulses; reconstructing a first image of the object by utilizing a Fourier transform technique and said first spin echo signal; reconstructing a second image by utilizing a Fourier transform technique and said second spin echo signal; and projecting an image of the object by selectively combining said first image and said second image, so that a restricted region of imaging is attained.
Claim 5
Dependent Claim
17 words
The method of claim 1, wherein said Fourier transform technique is a three dimension Fourier transform technique.
Claim 6
Dependent Claim
17 words
The method of claim 2, wherein said Fourier transform technique is a three dimension Fourier transform technique.
References Cited (Backward Citations)
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| 3.5 Years (Year 4) | 1995-02-17 | 1995-08-19 | 1996-02-18 | $2000.00 | Window Closed / Lapsed |
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