Patent US4947837A successfully refreshed from Google Patents.
US4947837A
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US
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Method of blood flow imaging
Assignee: Hitachi Healthcare Manufacturing Ltd
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Filing: 1989-07-13
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Granted: 1990-08-14
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Expires: 2009-07-13
Abstract
Abstract The blood flow imaging method excites selectively a partial region of the body to be tested including blood vessels inside or outside of the view field of image, measures resonance signals by utilizing spins flowing out of the excited region, and images a blood vessel system based on the blood flow information included in the measured resonance signals. The method images only blood vessels through a single shot of scanning, thereby reducing the time for scanning and enabling the observation of finer vessels.
Inventors
- 👤 Koichi Sano
- 👤 Tetsuo Yokoyama
- 👤 Hideaki Koizumi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 10:39
CPC Classifications
A; A61; A61B; A61B5/00; A61B5/02; A61B5/026; A61B5/0263
Claims Analysis
Total Claims: 23
Claim 1
Independent Claim
133 words
A method of imaging blood flows by means of a magnetic resonance imaging apparatus which includes means for generating a static magnetic field and gradient magnetic fields, means for generating a high-frequency (RF) magnetic field, means for detecting magnetic resonance signals from a body under test, and means for implementing an image-reproducing computation on the detected signals, said method comprising the steps of: exciting selectively a partial region of said test body including a blood vessel portion; measuring resonance signals by utilizing spins flowing out of said excited region; and imaging a blood vessel system based on blood flow information included in the measured resonance signals, wherein said partial region is set to a region which includes a region formed by extending a view field plane and is outside of the view field.
Claim 2
Independent Claim
133 words
A method of imaging blood flows by means of a magnetic resonance imaging apparatus which includes means for generating a static magnetic field and gradient magnetic fields, means for generating a high-frequency (RF) magnetic field, means for detecting magnetic resonance signals from a body under test, and means for implementing an image-reproducing computation on the detected signals, said method comprising the steps of: exciting selectively a partial region of said test body including a blood vessel portion; measuring resonance signals by utilizing spins flowing out of said excited region; and imaging a blood vessel system based on blood flow information included in the measured resonance signals, wherein said partial region is set to a region which includes a region formed by extending a view field plane and is outside of the view field.
Claim 3
Dependent Claim
21 words
A blood flow imaging method according to claim 1, wherein said measurement of resonance signals is implemented in a multi-echo mode.
Claim 4
Dependent Claim
29 words
A blood flow imaging method according to claim 2, wherein imaging is implemented by adding blood flow information reproduced from each of the signals measured in said multi-echo mode.
Claim 5
Dependent Claim
23 words
A blood flow imaging method according to claim 1, wherein said process of selective excitation includes a process of applying RF pulses successively.
Claim 6
Dependent Claim
26 words
A blood flow imaging method according to claim 4, wherein said RF pulses are applied for a variable number of times in a variable applying angle.
Claim 7
Dependent Claim
31 words
A blood flow imaging method according to claim 5, wherein said number of applying and angle of applying are varied depending on the portion to be scanned of said test body.
Claim 8
Dependent Claim
21 words
A blood flow imaging method according to claim 1, wherein said portion of selective excitation includes a part of the heart.
Claim 9
Dependent Claim
21 words
A blood flow imaging method according to claim 1, wherein said measuring process is synchronous with a pulsation of the heart.
Claim 10
Dependent Claim
23 words
A blood flow imaging method according to claim 1, wherein a flow velocity is measured on the basis of said blood flow information.
Claim 11
Independent Claim
146 words
A method of imaging blood flows by means of a magnetic resonance imaging apparatus which includes means for generating a static magnetic field and gradient magnetic fields, means for generating a high-frequency (RF) magnetic field, means for detecting magnetic resonance signals from a body under test, and means for implementing an image-reproducing computation on the detected signals, said method comprising the steps of: exciting selectively a partial region of said test body including a blood vessel portion; measuring resonance signals by utilizing spins flowing out of said excited region; and imaging a blood vessel system based on blood flow information included in the measured resonance signals, wherein said spins have a major flow direction set to a phase-encode direction and said partial region is set to a region which includes a region formed by extending a view field plane and is outside of the view field.
Claim 12
Independent Claim
146 words
A method of imaging blood flows by means of a magnetic resonance imaging apparatus which includes means for generating a static magnetic field and gradient magnetic fields, means for generating a high-frequency (RF) magnetic field, means for detecting magnetic resonance signals from a body under test, and means for implementing an image-reproducing computation on the detected signals, said method comprising the steps of: exciting selectively a partial region of said test body including a blood vessel portion; measuring resonance signals by utilizing spins flowing out of said excited region; and imaging a blood vessel system based on blood flow information included in the measured resonance signals, wherein said spins have a major flow direction set to a phase-encode direction and said partial region is set to a region which includes a region formed by extending a view field plane and is outside of the view field.
Claim 13
Dependent Claim
23 words
A blood flow imaging method according to claim 10, wherein said process of selective excitation includes a process of applying RF pulses successively.
Claim 14
Dependent Claim
26 words
A blood flow imaging method according to claim 11, wherein said RF pulses are applied for a variable number of times in a variable applying angle.
Claim 15
Dependent Claim
31 words
A blood flow imaging method according to claim 12, wherein said number of applying and angle of applying are varied depending on the portion to be scanned of said test body.
Claim 16
Independent Claim
146 words
A method of imaging blood flows by means of a magnetic resonance imaging apparatus which includes means for generating a static magnetic field and gradient magnetic fields, means for generating a high-frequency (RF) magnetic field, means for detecting magnetic resonance signals from a body under test, and means for implementing an image-reproducing computation on the detected signals, said method comprising the steps of: exciting selectively a partial region of said test body including a blood vessel portion; measuring resonance signals by utilizing spins flowing out of said excited region; and imaging a blood vessel system based on blood flow information included in the measured resonance signals, wherein said spins have a major flow direction set to a read-out direction and said partial region is set to a region which includes a region formed by extending a view field plane and is outside of the view field.
Claim 17
Independent Claim
146 words
A method of imaging blood flows by means of a magnetic resonance imaging apparatus which includes means for generating a static magnetic field and gradient magnetic fields, means for generating a high-frequency (RF) magnetic field, means for detecting magnetic resonance signals from a body under test, and means for implementing an image-reproducing computation on the detected signals, said method comprising the steps of: exciting selectively a partial region of said test body including a blood vessel portion; measuring resonance signals by utilizing spins flowing out of said excited region; and imaging a blood vessel system based on blood flow information included in the measured resonance signals, wherein said spins have a major flow direction set to a read-out direction and said partial region is set to a region which includes a region formed by extending a view field plane and is outside of the view field.
Claim 18
Dependent Claim
23 words
A blood flow imaging method according to claim 14, wherein said process of selective excitation includes a process of applying RF pulses successively.
Claim 19
Dependent Claim
26 words
A blood flow imaging method according to claim 15, wherein said RF pulses are applied for a variable number of times in a variable applying angle.
Claim 20
Dependent Claim
31 words
A blood flow imaging method according to claim 16, wherein said number of applying and angle of applying are varied depending on the portion to be scanned of said test body.
Claim 21
Dependent Claim
21 words
A blood flow imaging method according to claim 14, wherein said portion of selective excitation includes a part of the heart.
Claim 22
Dependent Claim
21 words
A blood flow imaging method according to claim 14, wherein said measuring process is synchronous with a pulsation of the heart.
Claim 23
Dependent Claim
23 words
A blood flow imaging method according to claim 14, wherein a flow velocity is measured on the basis of said blood flow information.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-08-13 | 1994-02-12 | 1994-08-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-08-13 | 1998-02-12 | 1998-08-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-08-13 | 2002-02-12 | 2002-08-14 | $7700.00 | Window Closed / Lapsed |