Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: A gradient coil and an insert gradient coil for a magnetic resonance imaging system include a primary coil. The primary coil includes an upper primary coil portion and a lower primary coil portion, the lower primary coil portion being less curved in cross-section than the upper primary coil portion. The gradient coil also includes a shielding coil disposed outside of the primary coil. The shielding coil includes an upper shielding coil portion and a lower shielding coil portion, the lower shielding coil portion being less curved in cross-section than the upper shielding coil portion.

Abstract: 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.

Abstract: 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.

Abstract: A gradient coil and an insert gradient coil for a magnetic resonance imaging system include a primary coil. The primary coil includes an upper primary coil portion and a lower primary coil portion, the lower primary coil portion being less curved in cross-section than the upper primary coil portion. The gradient coil also includes a shielding coil disposed outside of the primary coil. The shielding coil includes an upper shielding coil portion and a lower shielding coil portion, the lower shielding coil portion being less curved in cross-section than the upper shielding coil portion.

Abstract: Systems, methods and apparatus are provided through which in some embodiments a magnetic resonance imaging system includes at least two cryostats, each cryostat having a portion of a superconducting coil. Some embodiments provide force balancing between the sections. Some embodiments provide an ability to use more efficient superconducting coil geometry which would otherwise physically trap the gradient between the coils. Some embodiments provide an ability to install, remove or upgrade magnet without dismantling the imaging room.

Abstract: 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.

Abstract: 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.

Abstract: Systems, methods and apparatus are provided through which in some embodiments drift of a magnetic field of a magnetic resonance imaging (MRI) system is reduced by including a drift compensation coil which accumulates current at a rate proportional to the decay in the primary coil via its electromagnetic mutual inductance to the primary coil. In some embodiments, the drift compensation coil includes reverse turns at an outer radius, to significantly reduce any exacerbation of the fringe field during a quench of the primary coil. In further embodiments, the actively shielded drift compensation coil is complemented with a non-coupling external disturbance shield coil.

Abstract: A secondary coil circuit for use with a multi-section protected superconductive magnet coil circuit is disclosed herein. The secondary coil circuit includes two circuit nodes, a ramping switch electrically connected between the two circuit nodes, and a number of secondary coils electrically connected between the two circuit nodes. The secondary coils are made of wire having substantially superconductive capability when cooled below a characteristic critical temperature level and conducting electric current below a characteristic critical current level. The secondary coils are sized and positioned relative to the superconductive magnet coils situated in the individual sections of the multi-section protected superconductive magnet coil circuit so as to functionally cooperate with the multi-section protected superconductive magnet coil circuit in producing and maintaining a magnetic field that is substantially homogeneous.

Abstract: In this system and method for magnetic resonance imaging, an actively shielded primary coil includes a first and second set of turns each having a prescribed number of turns about an axis, and each being symmetrically positioned radially from the axis and equidistant with respect to a mid plane perpendicular to the axis. A secondary shielding coil includes a third and fourth set of turns each having a prescribed number of turns about the axis and being symmetrically positioned radially from the axis and equidistant with respect to the mid plane. The third set of turns is positioned in close proximity to the first set of turns and outward of the first set of turns. Likewise, the fourth set of turns is positioned in close proximity to the second set of turns and outward of the second set of turns. The first and third sets of turns are in a first prescribed turns ratio and the second and fourth sets of turns are in a second prescribed turns ratio.

Abstract: In this system and method for magnetic resonance imaging, an actively shielded primary coil includes a first and second set of turns each having a prescribed number of turns about an axis, and each being symmetrically positioned radially from the axis and equidistant with respect to a mid plane perpendicular to the axis. A secondary shielding coil includes a third and fourth set of turns each having a prescribed number of turns about the axis and being symmetrically positioned radially from the axis and equidistant with respect to the mid plane. The third set of turns is positioned in close proximity to the first set of turns and outward of the first set of turns. Likewise, the fourth set of turns is positioned in close proximity to the second set of turns and outward of the second set of turns. The first and third sets of turns are in a first prescribed turns ratio and the second and fourth sets of turns are in a second prescribed turns ratio.