Patent US5720939A successfully refreshed from Google Patents.
US5720939A
Expired / Lapsed
US
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Method of contrast enhanced magnetic resonance imaging using magnetically responsive-particles
Assignee: GE Healthcare AS
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Filing: 1995-06-06
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Granted: 1998-02-24
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Expires: 2015-06-06
Abstract
Abstract In a method of contrast MR imaging, using parenterally administered contrast agents, the improvement comprising using as the contrast agent, e.g. to achieve a negative contrast effect, composite particles comprising a biotolerable, carbohydrate or carbohydrate derivative, preferably polymeric, matrix material containing magnetically responsive particles, eg. of magnetite.
Inventors
- 👤 Ulf Schroder
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 04:48
CPC Classifications
A; A61; A61K; A61K49/00; A61K49/06; A61K49/18; A61K49/1818; A61K49/1887; A61K49/1821; Y; Y10; Y10T; Y10T436/00; Y10T436/24
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
88 words
In a method of contrast enhanced nuclear magnetic resonance diagnostic imaging which comprises administering into the vascular system of a subject a contrast enhancing amount of a nuclear magnetic resonance imaging contrast agent and generating an image of said subject, the improvement comprising administering as said contrast agent composite particles comprising a biotolerable, biodegradable carbohydrate or carbohydrate derivative, matrix material containing magnetically responsive particles, said magnetically responsive particles being of a material having a Curie temperature and said composite particles being no larger than one micrometer in size.
Claim 2
Dependent Claim
88 words
In a method of contrast enhanced nuclear magnetic resonance diagnostic imaging which comprises administering into the vascular system of a subject a contrast enhancing amount of a nuclear magnetic resonance imaging contrast agent and generating an image of said subject, the improvement comprising administering as said contrast agent composite particles comprising a biotolerable, biodegradable carbohydrate or carbohydrate derivative, matrix material containing magnetically responsive particles, said magnetically responsive particles being of a material having a Curie temperature and said composite particles being no larger than one micrometer in size.
Claim 3
Dependent Claim
20 words
A method as claimed in claim 1 wherein said composite particles are in the size range 0.010 to 1 μm.
Claim 4
Dependent Claim
17 words
A method as claimed in claim 1 wherein said composite particles comprise magnetically responsive particles of magnetite.
Claim 5
Dependent Claim
18 words
A method as claimed in claim 1 wherein said composite particles comprise magnetically responsive particles which are superparamagnetic.
Claim 6
Dependent Claim
16 words
A method as claimed in claim 3 wherein said composite particles contain 10-20 nm magnetite particles.
Claim 7
Dependent Claim
15 words
A method as claimed in claim 1 wherein said matrix material is a polymeric material.
References Cited (Backward Citations)
GB1174366A
Cited
US3663687A
Cited
US3720761A
Cited
US3832457A
Cited
GB1339537A
Cited
US3932805A
Cited
US4101435A
Cited
WO1978000005A1
Cited
US4247406A
Cited
US4331654A
Cited
WO1982001006A1
Cited
US4442843A
Cited
AU8633082A
Cited
US4501726A
Cited
WO1983003426A1
Cited
US4452773A
Cited
WO1983003920A1
Cited
WO1984000294A1
Cited
WO1984002643A1
Cited
GB2137612A
Cited
EP0136812A2
Cited
US4615879A
Cited
WO1985004330A1
Cited
US4675173A
Cited
US4849210A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2001-02-23 | 2001-08-25 | 2002-02-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2005-02-23 | 2005-08-25 | 2006-02-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2009-02-23 | 2009-08-25 | 2010-02-24 | $7700.00 | Window Closed / Lapsed |