US4841248A — Transverse field limited localized coil for magne…

Claim 1

Independent Claim 153 words

A magnetic resonance apparatus comprising: a main magnetic field generating means for generating a main magnetic field along a main field axis through an examination region; a magnetic resonance excitation means for exciting magnetic resonance of nuclei of a subject in the examination region; a localized coil assembly for receiving radio frequency signals from the resonating nuclei, the coil assembly including: an inner conductor defining a first current path along the main field axis and closely adjacent a surface of the subject, an outer conductor defining a current path along the main magnetic field axis, generally parallel to a surface of the subject and displaced further from the subject than the inner conductor, a connecting means for electrically connecting adjacent first ends of the inner and outer conductors; and, a coupling means connected adjacent second ends of the inner and outer conductors for interconnecting the conductors with a cable extending to a receiver.

Claim 2

Dependent Claim 153 words

A magnetic resonance apparatus comprising: a main magnetic field generating means for generating a main magnetic field along a main field axis through an examination region; a magnetic resonance excitation means for exciting magnetic resonance of nuclei of a subject in the examination region; a localized coil assembly for receiving radio frequency signals from the resonating nuclei, the coil assembly including: an inner conductor defining a first current path along the main field axis and closely adjacent a surface of the subject, an outer conductor defining a current path along the main magnetic field axis, generally parallel to a surface of the subject and displaced further from the subject than the inner conductor, a connecting means for electrically connecting adjacent first ends of the inner and outer conductors; and, a coupling means connected adjacent second ends of the inner and outer conductors for interconnecting the conductors with a cable extending to a receiver.

Claim 3

Dependent Claim 31 words

The apparatus as set forth in claim 1 wherein the outer conductor includes an outer plate extending parallel to the main field axis from the first end to the second end.

Claim 4

Dependent Claim 15 words

The apparatus as set forth in claim 2 wherein the outer conductive plate is flat.

Claim 5

Dependent Claim 15 words

The apparatus as set forth in claim 2 wherein the outer conductive plate is arcuate.

Claim 6

Dependent Claim 23 words

The apparatus as set forth in claim 4 wherein the outer plate is substantially cylindrical surrounding both the inner conductor and the subject.

Claim 7

Dependent Claim 28 words

The apparatus as set forth in claim 2 wherein the inner conductor is an inner plate extending along the main field axis between its first and second ends.

Claim 8

Dependent Claim 19 words

The apparatus as set forth in claim 6 wherein the inner and outer plates are parallel to each other.

Claim 9

Dependent Claim 21 words

The apparatus as set forth in claim 6 wherein the inner plate is generally flat and the outer plate is arcuate.

Claim 10

Dependent Claim 35 words

The apparatus as set forth in claim 1 wherein the connecting means and a portion of the inner conductor are surrounded by a first Faraday shield, which electrical shield is interconnected with the outer plate.

Claim 11

Dependent Claim 34 words

The apparatus as set forth in claim 9 further including at least one additional conductor disposed parallel to the inner conductor and surrounded by a second Faraday shield along a portion of its length.

Claim 12

Dependent Claim 41 words

The apparatus as set forth in claim 10 wherein the first and second shields are connected with the second plate adjacent the first and second ends and each shield has a gap therein, the gaps being in alignment with each other.

Claim 13

Dependent Claim 142 words

A localized coil for receiving magnetic resonance signals from resonating nuclei of a subject disposed in a magnetic field, the localized coil comprising: an inner conductive plate having first and second ends disposed adjacent and parallel to a surface of the subject and in alignment with the magnetic field; an outer conductive plate disposed adjacent and generally parallel to the inner conductive plate but further from the subject, the outer conductive plate being generally parallel to a surface of the subject and defining a conductive path extending in alignment with the magnetic field from a first end to a second end thereof; an electrical connecting means interconnecting first ends of the inner conductive plate and the outer conductive plate; and, a coupling means connected with second ends of the inner and outer conductive plates for connecting the coil with an electrical cable.

Claim 14

Dependent Claim 142 words

A localized coil for receiving magnetic resonance signals from resonating nuclei of a subject disposed in a magnetic field, the localized coil comprising: an inner conductive plate having first and second ends disposed adjacent and parallel to a surface of the subject and in alignment with the magnetic field; an outer conductive plate disposed adjacent and generally parallel to the inner conductive plate but further from the subject, the outer conductive plate being generally parallel to a surface of the subject and defining a conductive path extending in alignment with the magnetic field from a first end to a second end thereof; an electrical connecting means interconnecting first ends of the inner conductive plate and the outer conductive plate; and, a coupling means connected with second ends of the inner and outer conductive plates for connecting the coil with an electrical cable.

Claim 15

Dependent Claim 21 words

The coil as set forth in claim 12 wherein at least one of the inner and outer conductive plates is arcuate.

Claim 16

Dependent Claim 35 words

The coil as set forth in claim 12 wherein the outer conductive plate is larger at least along an axis transverse to the magnetic field than the inner conductive plate along a common transverse axis.

Claim 17

Dependent Claim 22 words

The coil as set forth in claim 12 wherein the coupling means includes a capacitive coupling between the inner and outer plates.

Claim 18

Dependent Claim 161 words

A localized coil for receiving magnetic resonance signals from resonating nuclei of a subject disposed in a magnetic field, the localized coil comprising: an inner electrical conductor having first and second ends disposed adjacent and parallel to a surface of the subject and in alignment with the magnetic field; an outer conductive plate disposed adjacent the inner conductor but further from the subject, the outer conductive plate being generally parallel to a surface of the subject and defining a conductive path extending in alignment with the magnetic field from a first end to a second end thereof; an electrical connecting means interconnecting first ends of the inner conductor and the outer conductive plate; a first shielding means extending from the outer conductive plate around the connecting means and partially along and around the inner conductor; and a coupling means connected with the second ends of the inner conductor and the outer conductive plate for connecting the coil with an electrical cable.

Claim 19

Dependent Claim 161 words

A localized coil for receiving magnetic resonance signals from resonating nuclei of a subject disposed in a magnetic field, the localized coil comprising: an inner electrical conductor having first and second ends disposed adjacent and parallel to a surface of the subject and in alignment with the magnetic field; an outer conductive plate disposed adjacent the inner conductor but further from the subject, the outer conductive plate being generally parallel to a surface of the subject and defining a conductive path extending in alignment with the magnetic field from a first end to a second end thereof; an electrical connecting means interconnecting first ends of the inner conductor and the outer conductive plate; a first shielding means extending from the outer conductive plate around the connecting means and partially along and around the inner conductor; and a coupling means connected with the second ends of the inner conductor and the outer conductive plate for connecting the coil with an electrical cable.

Claim 20

Dependent Claim 53 words

The coil as set forth in claim 16 further including an additional shielding means operatively connected with the outer plate adjacent the second end and extending along and around the inner conductor, the first and second shielding means defining a gap therebetween such that a small section of the inner conductor is exposed.

Claim 21

Dependent Claim 25 words

The coil as set forth in claim 17 further including a plurality of inner conductors and shielding means disposed in parallel along the magnetic field.

Claim 22

Dependent Claim 192 words

A magnetic resonance imaging apparatus comprising: a main magnetic field generating means for generating a main magnetic field along a main field axis through an image region; a magnetic resonance excitation means for exciting magnetic resonance of nuclei of a subject in the image region; a gradient field means for causing gradient magnetic fields across the main magnetic field; a receiving coil assembly for receiving radio frequency signals from the resonating nuclei, the coil assembly including: a first conductor disposed parallel to the main field axis and closely adjacent a surface of the subject, a second conductor having at least one radio frequency signal transmission aperture therethrough and extending along the main magnetic field axis and generally parallel to the surface of the subject, and displaced further from the subject than the first conductor, a connecting means for electrically connecting adjacent ends of the first and second conductors; a coupling means connected adjacent opposite ends of the first and second conductors from the connecting means for interconnecting the conductors with a cable; an image reconstruction means operatively connected with the cable for reconstructing a magnetic resonance image representation from the received signals.

Claim 23

Dependent Claim 192 words

A magnetic resonance imaging apparatus comprising: a main magnetic field generating means for generating a main magnetic field along a main field axis through an image region; a magnetic resonance excitation means for exciting magnetic resonance of nuclei of a subject in the image region; a gradient field means for causing gradient magnetic fields across the main magnetic field; a receiving coil assembly for receiving radio frequency signals from the resonating nuclei, the coil assembly including: a first conductor disposed parallel to the main field axis and closely adjacent a surface of the subject, a second conductor having at least one radio frequency signal transmission aperture therethrough and extending along the main magnetic field axis and generally parallel to the surface of the subject, and displaced further from the subject than the first conductor, a connecting means for electrically connecting adjacent ends of the first and second conductors; a coupling means connected adjacent opposite ends of the first and second conductors from the connecting means for interconnecting the conductors with a cable; an image reconstruction means operatively connected with the cable for reconstructing a magnetic resonance image representation from the received signals.

Claim 24

Dependent Claim 176 words

A magnetic resonance method comprising: disposing a subject in a magnetic resonance receiving coil arrangement which includes an inner conductor extending along a first axis, an outer conductor disposed parallel to the inner conductor and the first axis but displaced further from the subject than the inner conductor, a conductive connecting member for connecting first ends of the inner and outer conductors, and a capacitive coupling which is selected to provide a preselected receiving coil resonance frequency coupling the inner and outer conductors adjacent second ends thereof; generating a main magnetic field through the subject along the first axis parallel to the inner and outer conductors; exciting magnetic resonance of nuclei of the subject with radio frequency signals emanating further from the subject than the outer conductor such that magnetic resonance signals are generated by the nuclei within the subject; receiving the magnetic resonance signals with the inner and outer conductors such that corresponding currents are induced therein; processing the induced currents into a man-readable representation indicative of at least one characteristic of the resonating nuclei.

Claim 25

Dependent Claim 176 words

A magnetic resonance method comprising: disposing a subject in a magnetic resonance receiving coil arrangement which includes an inner conductor extending along a first axis, an outer conductor disposed parallel to the inner conductor and the first axis but displaced further from the subject than the inner conductor, a conductive connecting member for connecting first ends of the inner and outer conductors, and a capacitive coupling which is selected to provide a preselected receiving coil resonance frequency coupling the inner and outer conductors adjacent second ends thereof; generating a main magnetic field through the subject along the first axis parallel to the inner and outer conductors; exciting magnetic resonance of nuclei of the subject with radio frequency signals emanating further from the subject than the outer conductor such that magnetic resonance signals are generated by the nuclei within the subject; receiving the magnetic resonance signals with the inner and outer conductors such that corresponding currents are induced therein; processing the induced currents into a man-readable representation indicative of at least one characteristic of the resonating nuclei.

Annuity Stage	Window Opens	Payment Deadline	Surcharge Period Until	Estimated Fee	Status
3.5 Years (Year 4)	1992-06-19	1992-12-19	1993-06-20	$2000.00	Window Closed / Lapsed
7.5 Years (Year 8)	1996-06-19	1996-12-19	1997-06-20	$3760.00	Window Closed / Lapsed
11.5 Years (Year 12)	2000-06-19	2000-12-19	2001-06-20	$7700.00	Window Closed / Lapsed

Transverse field limited localized coil for magnetic resonance imaging

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