INDUCTIVELY POWERED ELECTRIC COMPONENT OF AN MRI APPARATUS

• US 20110084694A1
• Filed: 06/15/2009
• Published: 04/14/2011
• Est. Priority Date: 06/20/2008
• Status: Active Grant

• Current Assignee: Koninklijke Philips N.V.
• Original Assignee: Koninklijke Philips Electronics N.V. (Koninklijke Philips N.V.)
• Inventors: Reefman, Derk, Van Helvoort, Marinus Johannes Adrianus Maria, Blanden, Pieter Gerrit, De Vries, Lambertus, Hilgers, Achim, Weissler, Bjoern, Waffenschmidt, Eberhard
• Granted Patent: US 8,866,480 B2
• Time in Patent Office: Days
• US Class Current: 324/318
• CPC Class Codes: G01R 33/283 Intercom or optical viewing arrangements, structurally associated with NMR apparatus
• CPC Class Codes: G01R 33/3642 Mutual coupling or decoupling of multiple coils, e.g. decoupling of a receive coil from a transmission coil, or intentional coupling of RF coils, e.g. for RF magnetic field amplification
• CPC Class Codes: G01R 33/3692 involving signal transmission without using electrically conductive connections, e.g. wireless communication or optical communication of the MR signal or an auxiliary signal other than the MR signal
• CPC Class Codes: G01R 33/422 of the radio frequency field

Abstract

The invention relates to a nuclear magnetic resonance imaging apparatus comprising: a main magnet (122) adapted for generating a main magnetic field; at least one radio frequency receiver coil unit (144) for acquiring magnetic resonance signals in a receiver coil radio frequency band (202) from an examined object (124); means (140) for inductively (wirelessly) supplying electric power to an electric component of the apparatus, wherein the electric component is adapted to be powered by inductively supplied electric power, wherein the power transfer frequency (200) and the higher-harmonics (206) of the power transfer frequency (200) for inductively supplying the electric power are located outside the receiver coil radio frequency band (202).

Claims

1. A nuclear magnetic resonance imaging apparatus comprising:

a main magnet adapted for generating a main magnetic field;

at least one radio frequency receiver coil unit for acquiring magnetic resonance signals in a receiver coil radio frequency band from an examined object;

means for inductively supplying electric power to an electric component of the apparatus, wherein the electric component is adapted to be powered by inductively supplied electric power, wherein the power transfer frequency and the higher harmonics of the power transfer frequency for inductively supplying the electric power are located outside the receiver coil radio frequency band.

2. The apparatus of claim 1, wherein the electric component is the radio frequency receiver coil unit.

3. The apparatus of claim 1, wherein the main magnet comprises a magnet bore, wherein the electric component is spatially located within the magnet bore.

4. The apparatus of claim 1, further comprising means for determining at least one flanking frequency of the actually supplied higher harmonics of the power transfer frequency flanking the receiver coil radio frequency band, wherein the apparatus further comprises means r for adjusting the power transfer frequency using said determined flanking frequency.

5. The apparatus of claim 1, wherein the means for inductively supplying the electric power are adapted for supplying the electric power to the radio frequency receiver coil unit at time slices unused for magnetic resonance signal acquisition by the radio frequency receiver unit.

6. The apparatus of claim 1, further comprising a shielding tube, the shielding tube confining a magnetic resonance radio frequency excitation field generated by at least one radio frequency transmitter coil unit to an examination zone, the examination zone being adapted for receiving the examined object, the shielding tube being further penetrable for magnetic field gradients generated by magnetic field gradient coils located outside the shielding tube, the shielding tube featuring an electrical resonance frequency, wherein the power transfer frequency and the higher harmonics of the power transfer frequency are further located outside the shielding tube resonance frequency.

7. A nuclear magnetic resonance imaging apparatus comprising:

a main magnet adapted for generating a main magnetic field;

at least one radio frequency receiver coil unit for acquiring magnetic resonance signals in a receiver coil radio frequency band from an examined object;

means for inductively supplying electric power to an electric component of the apparatus, wherein the electric component is adapted to be powered by inductively supplied electric power, wherein the main magnet comprises a magnet bore, wherein the electric component is spatially located within the magnet bore, wherein the means for inductively supplying the electric power are adapted for supplying the electric power by a rotating magnetic field, wherein the rotation axis of the rotating magnetic field is parallel with the cylindrical axis of the main magnet.

8. The apparatus of claim 7, wherein the means for inductively supplying the electric power comprise a set of transmitter coils, wherein the windings of each transmitter coil of the set of transmitter coils span a plane, wherein all spanned planes of the set of transmitter coils intersect with a common axis, wherein said axis is in parallel with the cylindrical axis of the main magnet.

9. An electric component of a nuclear magnetic resonance imaging apparatus, the apparatus comprising a nuclear magnetic resonance imaging receiving coil unit for acquiring magnetic resonance signals in a receiver coil radio frequency band from an examined object, the electric component comprising means for inductively receiving electric power, wherein the power transfer frequency and the higher harmonics of the power transfer frequency are located outside the receiver coil radio frequency band.

10. The electric component unit of claim 9, wherein the means for inductively receiving electric power comprise a first coil adapted for inductively receiving the electric power, wherein the receiving coil unit further comprises a second coil adapted for receiving the magnetic resonance signals, wherein the first and the second coil are overlapping for a mutual electromagnetically decoupling of the first and second coil.

11. The electric component of claim 9, wherein the means for inductively receiving electric power comprise a set of coils adapted for inductively receiving the electric power, wherein each coil of the set of coils comprise a different number of coil windings.

12. A method of performing nuclear magnetic resonance imaging of an object, the method being performed by a nuclear magnetic resonance imaging apparatus, the method comprising:

exciting nuclear magnetization within the object;

inductively supplying electric power to an electric component of the apparatus, wherein the electric component is powered by inductively supplied electric power, the apparatus comprising a radio frequency receiver coil unit, the radio frequency receiver coil unit being adapted for acquiring magnetic resonance signals in a receiver coil radio frequency band from the object upon excitation of the object, wherein the power transfer frequency and the higher harmonics of the power transfer frequency for inductively supplying the electric power are located outside the receiver coil radio frequency band;

receiving the acquired magnetic resonance signals from the receiver coil unit.

13. The method of claim 12, further comprising determining at least one flanking frequency of the actually supplied higher harmonics of the power transfer frequency flanking the receiver coil radio frequency band, wherein the method further comprises adjusting the power transfer frequency using said determined flanking frequency.

15. A computer program product comprising computer executable instructions to perform any of the method steps as claimed in claim 12.

14. A method of acquiring magnetic resonance imaging signals in a receiver coil radio frequency band from an examined object, the method comprising:

inductively receiving electric power, wherein the power transfer frequency and the higher harmonics of the power transfer frequency are located outside the receiver coil radio frequency band;

acquiring the magnetic resonance signals from the examined object;

transmitting the acquired magnetic resonance signals to a nuclear magnetic resonance imaging apparatus.