US4617936A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Flexible surface coil for magnetic resonance imaging
Assignee: Philips North America LLC
•
Filing: 1985-08-08
•
Granted: 1986-10-21
•
Expires: 2005-08-08
Abstract
Abstract A surface coil for use with magnetic resonance imaging apparatus comprises an electrically-insulating, flexible tube which is filled with a liquid mercury conductor.
Inventors
- 👤 John A. Malko
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 14:10
CPC Classifications
G; G01; G01R; G01R33/00; G01R33/20; G01R33/28; G01R33/32; G01R33/34; G01R33/34007; G01R33/341; G01R33/34084
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
103 words
In magnetic resonance imaging apparatus of the type which includes: magnet means for generating a homogeneous magnetic field and one or more gradient magnetic fields within an examination space: exciting means for generating an alternating magnetic field within the examination space; and surface coils means disposed within the examination space and adapted for placement on the surface of a body undergoing examination for detecting magnetic resonance signals which originate within a localized volume in the body, the improvement wherein: the surface coil means comprises one or more turns of a flexible, electrically-insulating tube and an electrically-conductive liquid disposed within and filling said tube.
Claim 2
Dependent Claim
103 words
In magnetic resonance imaging apparatus of the type which includes: magnet means for generating a homogeneous magnetic field and one or more gradient magnetic fields within an examination space: exciting means for generating an alternating magnetic field within the examination space; and surface coils means disposed within the examination space and adapted for placement on the surface of a body undergoing examination for detecting magnetic resonance signals which originate within a localized volume in the body, the improvement wherein: the surface coil means comprises one or more turns of a flexible, electrically-insulating tube and an electrically-conductive liquid disposed within and filling said tube.
Claim 3
Dependent Claim
14 words
The apparatus of claim 1 wherein the surface coil means is a single-turn coil.
Claim 4
Dependent Claim
11 words
The apparatus of claim 1 wherein the conductive liquid is mercury.
Claim 5
Independent Claim
18 words
The apparatus of claims 1 or 2 wherein the surface coil means is effectively free of paramagnetic materials.
Claim 6
Dependent Claim
12 words
The apparatus of claim 4 wherein the conductive liquid is triple-distilled mercury.
Claim 7
Dependent Claim
16 words
The apparatus of claim 5 further comprising copper electrodes disposed in contact with the liquid mercury.
Claim 8
Dependent Claim
42 words
The apparatus of claim 1 further comprising decoupling means, connected to the surface coil means, which detune the resonant frequency of the surface coil means at such times as the exciting means is producing an alternating magnetic field in the examination space.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-10-20 | 1990-04-21 | 1990-10-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-10-20 | 1994-04-21 | 1994-10-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-10-20 | 1998-04-21 | 1998-10-21 | $7700.00 | Window Closed / Lapsed |