Abstract: Systems and methods for tomographic reconstruction of an image include systems and methods for producing images from k-space data. A k-space data set of an imaged object is acquired using know k-space data acquisition systems and methods. A portion of the k-space data set is sampled so as to collect some portion of the k-space data. An image is then reconstructed from the collected portion of the k-space data set according to a convex optimization model.

Abstract: Systems and methods for the delivery of linear accelerator radiotherapy in conjunction with magnetic resonance imaging in which components of a linear accelerator may be placed in shielding containers around a gantry, may be connected with RF waveguides, and may employ various systems and methods for magnetic and radio frequency shielding.

Abstract: A radiation therapy system comprises a magnetic resonance imaging (MRI) system combined with an irradiation system, which can include one or more linear accelerators (linacs) that can emit respective radiation beams suitable for radiation therapy. The MRI system includes a split magnet system, comprising first and second main magnets separated by gap. A gantry is positioned in the gap between the main MRI magnets and supports the linac(s) of the irradiation system. The gantry is rotatable independently of the MRI system and can angularly reposition the linac(s). Shielding can also be provided in the form of magnetic and/or RF shielding. Magnetic shielding can be provided for shielding the linac(s) from the magnetic field generated by the MRI magnets. RF shielding can be provided for shielding the MRI system from RF radiation from the linac.

Abstract: A magnetic resonance imaging (MRI) system includes a split magnet system having a pair of MRI magnet housings separated by gap. A pair of main MRI magnets are disposed within respective MRI magnet housings. A plurality of buttress assemblies are attached to the MRI magnet housings. Some or all of the buttress assemblies are provided with removable connections to the MRI magnet housings. This allows for partial disassembly of the MRI system for improved transport and maneuverability for relocating the MRI system. The MRI system can include a gantry in the gap for supporting a radiation therapy system. Also, the removably buttress assemblies can be used for housing conduits, such as electrical and fluid conduits, between the pair of MRI magnet housings.

Abstract: Active resistive shim coil assemblies may be used in magnetic resonance imaging (MRI) systems to reduce in-homogeneity of the magnetic field in the imaging volume. Disclosed embodiments may be used with continuous systems, gapped cylindrical systems, or vertically gapped systems. Disclosed embodiments may also be used with an open MRI system and can be used with an instrument placed in the gap of the MRI system. An exemplary embodiment of the active resistive shim coil assembly of the present disclosure includes active resistive shim coils each operable to be energized by separate currents through a plurality of power channels. In some embodiments, the disclosed active resistive shim coil assemblies allow for various degrees of freedom to shim out field in-homogeneity.

Abstract: Gradient coil assemblies for horizontal magnetic resonance imaging systems (MRIs) and methods of their manufacture. Some embodiments may be used with open MRIs and can be used with an instrument placed in the gap of the MRI. In general, concentrations of conductors or radially oriented conductors may be moved away from the gap of the MRI so as to reduce eddy currents that may be induced in any instrument placed within the gap. Systems for directly cooling primary gradient and shield coils may be utilized and various coil supporting structures may be used to assist in coil alignment or to facilitate use of an instrument in the MRI gap.

Abstract: A radiation therapy system comprises a magnetic resonance imaging (MRI) system combined with an irradiation system, which can include one or more linear accelerators (linacs) that can emit respective radiation beams suitable for radiation therapy. The MRI system includes a split magnet system, comprising first and second main magnets separated by gap. A gantry is positioned in the gap between the main MRI magnets and supports the linac(s) of the irradiation system. The gantry is rotatable independently of the MRI system and can angularly reposition the linac(s). Shielding can also be provided in the form of magnetic and/or RF shielding. Magnetic shielding can be provided for shielding the linac(s) from the magnetic field generated by the MRI magnets. RF shielding can be provided for shielding the MRI system from RF radiation from the linac.

Abstract: A magnetic resonance imaging (MRI) system includes a split magnet system having a pair of MRI magnet housings separated by gap. A pair of main MRI magnets are disposed within respective MRI magnet housings. A plurality of buttress assemblies are attached to the MRI magnet housings. Some or all of the buttress assemblies are provided with removable connections to the MRI magnet housings. This allows for partial disassembly of the MRI system for improved transport and maneuverability for relocating the MRI system. The MRI system can include a gantry in the gap for supporting a radiation therapy system. Also, the removably buttress assemblies can be used for housing conduits, such as electrical and fluid conduits, between the pair of MRI magnet housings.

Abstract: Gradient coil assemblies for horizontal magnetic resonance imaging systems (MRIs) and methods of their manufacture. Some embodiments may be used with open MRIs and can be used with an instrument placed in the gap of the MRI. In general, concentrations of conductors or radially oriented conductors may be moved away from the gap of the MRI so as to reduce eddy currents that may be induced in any instrument placed within the gap. Systems for directly cooling primary gradient and shield coils may be utilized and various coil supporting structures may be used to assist in coil alignment or to facilitate use of an instrument in the MRI gap.

Abstract: Systems and methods for the delivery of linear accelerator radiotherapy in conjunction with magnetic resonance imaging in which components of a linear accelerator may be placed in shielding containers around a gantry, may be connected with RF waveguides, and may employ various systems and methods for magnetic and radio frequency shielding.

Abstract: Systems and methods for delivery of radiotherapy in conjunction with magnetic resonance imaging in which various conductors, shields and shims may be used to solve issues occurring when radiation therapy equipment is placed in the vicinity of an magnetic resonance imaging system.

Abstract: A radiation therapy system comprises a magnetic resonance imaging (MRI) system combined with an irradiation system, which can include one or more linear accelerators (linacs) that can emit respective radiation beams suitable for radiation therapy. The MRI system includes a split magnet system, comprising first and second main magnets separated by gap. A gantry is positioned in the gap between the main MRI magnets and supports the linac(s) of the irradiation system. The gantry is rotatable independently of the MRI system and can angularly reposition the linac(s). Shielding can also be provided in the form of magnetic and/or RF shielding. Magnetic shielding can be provided for shielding the linac(s) from the magnetic field generated by the MRI magnets. RF shielding can be provided for shielding the MRI system from RF radiation from the linac.

Abstract: A magnetic resonance imaging (MRI) system includes a split magnet system having a pair of MRI magnet housings separated by gap. A pair of main MRI magnets are disposed within respective MRI magnet housings. A plurality of buttress assemblies are attached to the MRI magnet housings. Some or all of the buttress assemblies are provided with removable connections to the MRI magnet housings. This allows for partial disassembly of the MRI system for improved transport and maneuverability for relocating the MRI system. The MRI system can include a gantry in the gap for supporting a radiation therapy system. Also, the removably buttress assemblies can be used for housing conduits, such as electrical and fluid conduits, between the pair of MRI magnet housings.

Abstract: A magnetic resonance imaging (MRI) system includes a split magnet system having a pair of MRI magnet housings separated by gap. A pair of main MRI magnets are disposed within respective MRI magnet housings. A plurality of buttress assemblies are attached to the MRI magnet housings. Some or all of the buttress assemblies are provided with removable connections to the MRI magnet housings. This allows for partial disassembly of the MRI system for improved transport and maneuverability for relocating the MRI system. The MRI system can include a gantry in the gap for supporting a radiation therapy system. Also, the removably buttress assemblies can be used for housing conduits, such as electrical and fluid conduits, between the pair of MRI magnet housings.

Abstract: Gradient coil assemblies for horizontal magnetic resonance imaging systems (MRIs) and methods of their manufacture. Some embodiments may be used with open MRIs and can be used with an instrument placed in the gap of the MRI. In general, concentrations of conductors or radially oriented conductors may be moved away from the gap of the MRI so as to reduce eddy currents that may be induced in any instrument placed within the gap. Systems for directly cooling primary gradient and shield coils may be utilized and various coil supporting structures may be used to assist in coil alignment or to facilitate use of an instrument in the MRI gap.

Abstract: A radiation therapy system comprises a magnetic resonance imaging (MRI) system combined with an irradiation system, which can include one or more linear accelerators (linacs) that can emit respective radiation beams suitable for radiation therapy. The MRI system includes a split magnet system, comprising first and second main magnets separated by gap. A gantry is positioned in the gap between the main MRI magnets and supports the linac(s) of the irradiation system. The gantry is rotatable independently of the MRI system and can angularly reposition the linac(s). Shielding can also be provided in the form of magnetic and/or RF shielding. Magnetic shielding can be provided for shielding the linac(s) from the magnetic field generated by the MRI magnets. RF shielding can be provided for shielding the MRI system from RF radiation from the linac.

Abstract: Systems and methods for tomographic reconstruction of an image include systems and methods for producing images from k-space data. A k-space data set of an imaged object is acquired using know k-space data acquisition systems and methods. A portion of the k-space data set is sampled so as to collect some portion of the k-space data. An image is then reconstructed from the collected portion of the k-space data set according to a convex optimization model.

Abstract: A transverse magnetic field gradient coil includes a set of primary coil loops (62) defining an operative coil end (66) and a distal coil end (68). The set of primary coil loops are configured to generate a magnetic field gradient in a selected region asymmetrically disposed relatively closer to the operative coil end and relatively further from the distal coil end. A set of shield coil loops (64) are disposed outside the set of primary coil loops and are configured to substantially shield the set of primary coil loops. Two or more current jumps (70) are disposed at the distal end. Each current jump electrically connects an incomplete loop of the set of primary coil loops with an incomplete loop of the set of shield coil loops.

Abstract: In a magnetic resonance imaging system (10), a main magnet (20) generates a substantially uniform main magnetic field (B0) through an examination region (14). An imaging subject (16) generates inhomogeneities in the main magnetic field (B0). One or more shim coils are positioned adjacent a gradient coil (26). The gradient coil (26) is driven in halves by first and second power sources (28, 30) which have slightly dissimilar power characteristics which induce an inductive coupling between the shim coil (60) and the gradient coil (26). The shim coil (60) is designed to produce a desired magnetic field, such that the inductive coupling of the shim coils (60) to the gradient coil (26) is substantially minimized while the inhomogeneities in the main magnetic field (B0) caused by the imaging subject are corrected based on prespecified spatial characteristics.

Abstract: A gradient coil for a magnetic resonance imaging apparatus (10) includes a primary coil (16) defining an inner cylindrical surface (60), and shield coil (18) or coils defining a coaxial outer cylindrical surface (62). Coil jumps (74)connect the primary and shield coils (16, 18). The coil jumps (74) define a non-planar current-sharing surface (64) extending between inner and outer contours (66, 68) that coincide with the inner and outer cylindrical surfaces (60, 62), respectively. The coil (16, 18, 74) defines a current path that passes across the current sharing surface (64) between the inner and outer contours (66, 68) a plurality of times. Optionally, some primary coil turns (70) are electrically interconnected to define an isolated primary sub coil (P2) that together with a second shield (S2, S2?, S2?) enables a discretely or continuously selectable field of view.