US4845430A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Magnetic resonance imaging system
Assignee: Toshiba Corp
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Filing: 1987-06-29
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Granted: 1989-07-04
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Expires: 2007-06-29
Abstract
Abstract A magnetic resonance imaging system includes a field generation section, an excitation section, an excitation control section, a resonance data acquisition section, and an image generation section. The field generation section generates a static magnetic field, a gradient magnetic field, and a selective excitation pulse. The excitation section controls the field generation section to apply the static field, the gradient field, and the pulse to an object, at a predetermined timing, to selectively excite a magnetic resonance phenomenon in a specific slice of the object. The excitation control section controls the excitation section to excite a plurality of slices. The excitation control section causes the excitation section to excite a certain slice of the object, and causes the excitation section to excite another slice, separated from the previous slice at least by a thickness of the slice determined by the selective excitation pulse, within an excitation-repeating time. The resonance data acquisition section detects a signal induced by the magnetic resonance, to acquire data relating to the resonance. The image generation section generates an image on the basis of the resonance data.
Inventors
- 👤 Kazuto Nakabayashi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 13:47
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
219 words
A magnetic resonance imaging system comprising: magnetic field generating means for generating a static magnetic field, a gradient magnetic field, and a selective excitation pulse, to be applied to an object being examined; excitation means for causing said magnetic field generating means to apply the static magnetic field, the gradient magnetic field, and the excitation pulse to the object being examined, at a predetermined timing, thereby selectively exciting a magnetic resonance phenomenon in a specific slice of the object being examined; excitation control means including means for causing said excitation means to excite a certain slice of the object being examined, and then causing said excitation means to excite a next successive, non-contiguous slice, separated from said certain slice by at least the thickness of a single slice, said next successive, non-contiguous slice excited subsequently by the selective excitation pulse with a corresponding magnetic gradient, within an excitation-repeating time of the slice, said excitation control means controlling said excitation means so as to excite a plurality of contiguous slices; resonance data acquisition means for detecting a magnetic resonance signal induced by magnetic resonance excited by said excitation control means, to acquire data relating to resonance; and image generating means for generating a magnetic resonance image on the basis of the resonance data acquired by said resonance data acquisition means.
Claim 2
Dependent Claim
219 words
A magnetic resonance imaging system comprising: magnetic field generating means for generating a static magnetic field, a gradient magnetic field, and a selective excitation pulse, to be applied to an object being examined; excitation means for causing said magnetic field generating means to apply the static magnetic field, the gradient magnetic field, and the excitation pulse to the object being examined, at a predetermined timing, thereby selectively exciting a magnetic resonance phenomenon in a specific slice of the object being examined; excitation control means including means for causing said excitation means to excite a certain slice of the object being examined, and then causing said excitation means to excite a next successive, non-contiguous slice, separated from said certain slice by at least the thickness of a single slice, said next successive, non-contiguous slice excited subsequently by the selective excitation pulse with a corresponding magnetic gradient, within an excitation-repeating time of the slice, said excitation control means controlling said excitation means so as to excite a plurality of contiguous slices; resonance data acquisition means for detecting a magnetic resonance signal induced by magnetic resonance excited by said excitation control means, to acquire data relating to resonance; and image generating means for generating a magnetic resonance image on the basis of the resonance data acquired by said resonance data acquisition means.
Claim 3
Dependent Claim
39 words
A system according to claim 1, wherein said excitation control means comprises means for sequentially exciting a plurality of odd-numbered slices, from one end of said plurality of contiguous slices, and then sequentially exciting a plurality of even-numbered slices.
Claim 4
Dependent Claim
39 words
A system according to claim 1, wherein said excitation control means comprises means for sequentially exciting a plurality of even-numbered slices, from one end of said plurality of contiguous slices, and then sequentially exciting a plurality of odd-numbered slices.
Claim 5
Independent Claim
269 words
A method of obtaining a magnetic resonance image of a plurality of slices of an object being examined, in a magnetic resonance imaging system for applying a static magnetic field, a gradient magnetic field, and a selective excitation pulse to the object being examined, at a predetermined timing, to selectively excite a magnetic resonance phenomenon in a slice of the object being examined, detecting a magnetic resonance signal induced by excited magnetic resonance, and generating the magnetic resonance image on the basis of the magnetic resonance signal, said method comprising: a first step of applying, at a predetermined timing, a predetermined static magnetic field, a gradient magnetic field, and an excitation pulse to the object being examined, to selectively excite a magnetic resonance phenomenon in a predetermined slice of said object; a second step of detecting a magnetic resonance signal induced by magnetic resonance excited in the first step; a third step of applying, at a predetermined timing, a predetermined static magnetic field, a gradient magnetic field, and an excitation pulse to the object being examined, after the magnetic resonance signal is detected, and selectively exciting the magnetic resonance phenomenon in a successive slice, separated from a previously excited slice by at least the thickness of a single slice, said successive slice excited subsequently by the selective excitation pulse with a corresponding magnetic gradient, within an excitation-repeating time of the slice; a fourth step of detecting a magnetic resonance signal induced by magnetic resonance excited in the third step; and a fifth step of repeating the third and fourth steps so as to excite a plurality of contiguous slices.
Claim 6
Independent Claim
269 words
A method of obtaining a magnetic resonance image of a plurality of slices of an object being examined, in a magnetic resonance imaging system for applying a static magnetic field, a gradient magnetic field, and a selective excitation pulse to the object being examined, at a predetermined timing, to selectively excite a magnetic resonance phenomenon in a slice of the object being examined, detecting a magnetic resonance signal induced by excited magnetic resonance, and generating the magnetic resonance image on the basis of the magnetic resonance signal, said method comprising: a first step of applying, at a predetermined timing, a predetermined static magnetic field, a gradient magnetic field, and an excitation pulse to the object being examined, to selectively excite a magnetic resonance phenomenon in a predetermined slice of said object; a second step of detecting a magnetic resonance signal induced by magnetic resonance excited in the first step; a third step of applying, at a predetermined timing, a predetermined static magnetic field, a gradient magnetic field, and an excitation pulse to the object being examined, after the magnetic resonance signal is detected, and selectively exciting the magnetic resonance phenomenon in a successive slice, separated from a previously excited slice by at least the thickness of a single slice, said successive slice excited subsequently by the selective excitation pulse with a corresponding magnetic gradient, within an excitation-repeating time of the slice; a fourth step of detecting a magnetic resonance signal induced by magnetic resonance excited in the third step; and a fifth step of repeating the third and fourth steps so as to excite a plurality of contiguous slices.
Claim 7
Dependent Claim
48 words
A method according to claim 4, wherein said first and second steps include the step of applying one or a combination of a plurality of the static magnetic field, the gradient magnetic field, and the excitation pulse to the object being examined, in accordance with a predetermined sequence.
Claim 8
Dependent Claim
14 words
A method according to claim 4 wherein a plurality of slices are contiguous slices.
References Cited (Backward Citations)
US4115730A
Cited
US4297637A
Cited
US4318043A
Cited
US4411270A
Cited
US4458203A
Cited
US4509015A
Cited
US4599565A
Cited
US4665467A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-07-03 | 1993-01-02 | 1993-07-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-07-03 | 1997-01-02 | 1997-07-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-07-03 | 2001-01-02 | 2001-07-04 | $7700.00 | Window Closed / Lapsed |