CONTROL APPARATUS FOR A MAGNETIC RESONANCE IMAGING ANTENNA ARRANGEMENT

• US 20090201022A1
• Filed: 02/11/2009
• Published: 08/13/2009
• Est. Priority Date: 02/11/2008
• Status: Active Grant

• Current Assignee: Siemens Healthcare GMBH (Siemens AG)
• Original Assignee: Siemens AG
• Inventors: Schnell, Wilfried, Renz, Wolfgang, Oppelt, Ralph
• Granted Patent: US 7,977,944 B2
• Time in Patent Office: Days
• US Class Current: 324/322
• CPC Class Codes: G01R 33/3403 Means for cooling of the RF coils, e.g. a refrigerator or a cooling vessel specially adapted for housing an RF coil
• CPC Class Codes: G01R 33/34046 Volume type coils, e.g. bird-cage coils; Quadrature bird-cage coils; Circularly polarised coils
• CPC Class Codes: G01R 33/34076 Birdcage coils
• CPC Class Codes: G01R 33/3415 comprising arrays of sub-coils , i.e. phased-array coils with flexible receiver channels
• CPC Class Codes: G01R 33/3614 RF power amplifiers
• CPC Class Codes: G01R 33/5659 caused by a distortion of the RF magnetic field, e.g. spatial inhomogeneities of the RF magnetic field G01R33/56509, G01R33/56518, G01R33/56536 take precedence

Abstract

An apparatus to control an antenna arrangement in a magnetic resonance apparatus has an amplifier with an input connected to a radio-frequency transmission signal to be amplified. The antenna arrangement has at least one antenna element for emission of the amplified transmission signal. The antenna element has an infeed point with two terminals, wherein the amplified transmission signal is connected at the terminals. The amplifier is connected on the output side with two terminals of the infeed point. The antenna element has at the infeed point, a mounting surface to accommodate the amplifier.

Claims

1. A control apparatus for an antenna, comprising:

an amplifier having an input supplied with a radio-frequency transmission signal that is amplified in said amplifier, said amplifier having an amplifier output at which the amplified radio-frequency transmission signal is emitted;

an antenna arrangement comprising at least one antenna element configured to emit the amplified radio-frequency transmission signal in a magnetic resonance apparatus;

said antenna element comprises an infeed point with two terminals connected to said amplifier output to receive said amplified radio-frequency transmission signal therefrom; and

said antenna element comprising, at said infeed point, a mounting surface on which said amplifier is mounted.

2. A control apparatus as claimed in claim 1 comprising a heat-conductive mounting that mounts the amplifier to said mounting surface to make at least a portion of said antenna arrangement a heat sink for said amplifier.

3. A control apparatus as claimed in claim 1 wherein said antenna arrangement is selected from the group consisting of cylindrical antenna arrangements, Frustum-shaped antenna arrangements, and birdcage antenna arrangements.

4. A control apparatus as claimed in claim 1 wherein said antenna arrangement comprises a plurality of longitudinal rods each having opposite ends, and two termination rods respectively disposed at the opposite ends of said longitudinal rods that electrically connect said longitudinal rods to each other, and a plurality of amplifiers, including said amplifier, connected respectively to a plurality of infeed points distributed around said terminal rings or said longitudinal rods, and a plurality of mounting surfaces at said antenna arrangement at which said plurality of amplifiers are respectively mounted, each amplifier and the infeed point connected thereto forming a channel of a multi-channel transmission system.

6. A control apparatus as claimed in claim 1 wherein said antenna element comprises a hollow space at said input point, and wherein said mounting surface is located in said hollow space, said hollow space shielding said amplifier from radiation by said antenna arrangement.

7. A control apparatus as claimed in claim 1 wherein said amplifier comprises a shielding that shields said amplifier against radiation by said antenna arrangement.

8. A control apparatus as claimed in claim 1 comprising a cooling system in thermal communication with said antenna arrangement to cool said antenna arrangement.

9. A control apparatus as claimed in claim 8 comprising an injected error system that additionally cools said antenna arrangement by injected air.

10. A control apparatus as claimed in claim 8 wherein said antenna arrangement is connected at selected points with coolant-carrying conduits.

11. A control apparatus as claimed in claim 8 comprising a radio-frequency shield that two-dimensionally surrounds said antenna arrangement, said radio-frequency shield also being thermally conductive to transfer heat away from said antenna arrangement.

12. A control apparatus as claimed in claim 8 comprising a plurality of hollow antenna structures that contain and carry a coolant that additionally cools said antenna arrangement.