摘要:
A coil assembly for a Magnetic Resonance Imaging (MRI) system includes a primary gradient coil, and a corrector coil, at least a portion of the corrector coil being interwoven with a portion of the primary gradient coil such that the portion of the primary gradient coil is concentric with the portion of the corrector coil. An MRI imaging system and a method of fabricating the coil assembly are also provided.
摘要:
A superconducting magnet system includes a coil support structure, superconducting coils, and electrically and thermally conductive windings. The superconducting coils and the conductive windings are supported by the coil support structure. Each conductive winding is electromagnetically coupled with a corresponding superconducting coil. Each conductive winding is electrically shorted.
摘要:
Systems, methods and apparatus are provided through which inhomogeneity in a magnetic field is reduced by invoking electromagnetic mutual inductance between a main coil and another coil.
摘要:
A gradient coil is provided. The gradient coil comprises: a first layer comprised of a first plurality of turns of wires; and a second layer of coil comprised of a second plurality of turns of wires. Each turn of wire in the first and second plurality of turns of wires circles along the side walls of a cylindrical substrate and each turn of wire in the first and second plurality of turns of wires include a first portion wound along the inner side wall of the substrate and a second portion wound along the outer side wall of the substrate.
摘要:
A superconducting magnet system includes a coil support structure, superconducting coils, and electrically and thermally conductive windings. The superconducting coils and the conductive windings are supported by the coil support structure. Each conductive winding is electromagnetically coupled with a corresponding superconducting coil. Each conductive winding is electrically shorted.
摘要:
Systems and methods for operating a magnetic resonance imaging (MRI) during ramping are provided. One method includes reducing pressure in a cryogen vessel of an MRI system during magnet ramping. The method also includes returning pressure in the cryogen vessel to a normal operating pressure level after magnet ramping is complete.
摘要:
Methods, systems and computer program products are described for providing gradient linearity correction in a magnetic resonance image. The method in one example obtains, using a simulation, a time-dependent eddy current induced magnetic gradient field produced by a gradient system in response to a gradient switching pulse. Subsequently, the method determines time-dependent eddy current harmonic response coefficients for at least one higher harmonic frequency based upon the time-dependent eddy current induced magnetic gradient field. The method then corrects the magnetic resonance image based upon the time-dependent eddy current harmonic response coefficients.
摘要:
Systems and methods for operating a magnetic resonance imaging (MRI) during ramping are provided. One method includes reducing pressure in a cryogen vessel of an MRI system during magnet ramping. The method also includes returning pressure in the cryogen vessel to a normal operating pressure level after magnet ramping is complete.
摘要:
Systems, methods and apparatus are provided through which a partially elongated field-of-view in a magnetic resonance imaging system is generated either by an asymmetric primary coil or a conventional symmetrical primary coil with a supplementary high odd-order shim that elongates the field-of-view towards one end of the bore. For significantly increased efficiency, the high odd-order shim can evoke specific parts of the primary coil by injecting additional current and/or subtracting current from specific turns, as required.
摘要:
A superconducting magnet system includes a coil support structure, superconducting coils, and electrically and thermally conductive windings. The superconducting coils and the conductive windings are supported by the coil support structure. Each conductive winding is electromagnetically coupled with a corresponding superconducting coil. Each conductive winding is electrically shorted.