Ferromagnetic frame for magnetic resonance imaging
An apparatus for providing a B 0 magnetic field for a magnetic resonance imaging system. The apparatus includes at least one permanent B 0 magnet to contribute a magnetic field to the B 0 magnetic field for the MRI system and a ferromagnetic frame configured to capture and direct at least some of the magnetic field generated by the B 0 magnet. The ferromagnetic frame includes a first plate configured to support the at least one permanent B 0 magnet and a first post attached to the first plate using a first connection assembly, wherein the first connection assembly includes a first connector that connects the first post and the first plate and a second connector attached to the first connector.
1. An apparatus for providing a B 0 magnetic field for a magnetic resonance imaging (MRI) system, the apparatus comprising:
at least one permanent B 0 magnet to contribute a magnetic field to the B 0 magnetic field for the MRI system; and
a ferromagnetic frame configured to capture and direct at least some of the magnetic field generated by the at least one permanent B 0 magnet, the ferromagnetic frame comprising:
a first plate configured to support the at least one permanent B 0 magnet; and
a first post attached to the first plate using a first connection assembly, wherein the first connection assembly includes:
a first connector that connects the first post and the first plate; and
a second connector attached to the first connector; and
at least one permanent magnet coupled to an interior face of the first post.
2. The apparatus of claim 1 , the ferromagnetic frame further comprising:
a second post attached to the first plate using a second connection assembly, wherein the second connection assembly includes:
a third connector that connects the second post and the first plate; and
a fourth connector attached to the third connector.
3. The apparatus of claim 2 , the ferromagnetic frame further comprising:
a second plate disposed opposite the first plate and configured to support the at least one permanent B 0 magnet, wherein:
the second plate is attached to the first post using a third connection assembly and to the second post using a fourth connection assembly, wherein:
the third connection assembly includes:
a fifth connector that connects the first post to the second plate; and
a sixth connector attached to the fifth connector; and
the fourth connection assembly includes:
a seventh connector that connects the second post to the second plate; and
an eighth connector attached to the seventh connector.
4. The apparatus of claim 3 , wherein the first plate and the second plate each comprise one or more holes.
5. The apparatus of claim 1 , wherein the first connector comprises a ferromagnetic plate.
6. The apparatus of claim 5 , wherein the first connector comprises silicon steel.
7. The apparatus of claim 1 , wherein the first connector is secured to the first post and the first plate using multiple fasteners.
8. The apparatus of claim 1 , wherein the second connector is secured to the first post by multiple fasteners passing through the first connector.
9. The apparatus of claim 1 , wherein the at least one permanent magnet comprises a cylindrical permanent magnet.
10. The apparatus of claim 9 , wherein the at least one permanent magnet comprises a first permanent magnet and a second permanent magnet, the first and second permanent magnets being disposed along a length of the first post.
11. The apparatus of claim 10 , wherein the first permanent magnet has a first polarization and the second permanent magnet has a second polarization opposite the first polarization.
12. The apparatus of claim 11 , wherein one of the first and second polarizations is directed toward the interior face of the first post.
13. A magnetic resonance imaging system, comprising:
the apparatus of claim 1 ;
a plurality of gradient coils configured to, when operated, generate magnetic fields to provide spatial encoding of emitted magnetic resonance signals;
at least one radio frequency transmit coil; and
a power system configured to provide power to the plurality of gradient coils and the at least one radio frequency transmit coil.
14. A method, comprising:
imaging a patient using a magnetic resonance imaging (MRI) system, the MRI system comprising:
at least one permanent B 0 magnet to contribute a magnetic field to a B 0 magnetic field for the MRI system; and
a ferromagnetic frame configured to capture and direct at least some of the magnetic field generated by the at least one permanent B 0 magnet, the ferromagnetic frame comprising:
a first plate configured to support the at least one permanent B 0 magnet; and
a first post attached to the first plate using a first connection assembly, wherein the first connection assembly includes:
a first connector that connects the first post and the first plate; and
a second connector attached to the first connector; and
at least one permanent magnet coupled to an interior face of the first post.