Abstract: An ion chamber has a chamber having an interior volume. There is a first electrode and a second electrode in the chamber and separated by a gap. A collector electrode is positioned between the first electrode and the second electrode. The collector electrode is shaped to occlude a portion of the first electrode from the second electrode.

Abstract: A magnetic resonance imaging (MRI) system having a resistive, solenoidal electromagnet for whole-body MRI may include ferromagnetic material within an envelope of the electromagnet. The system can be configured to have a field strength of at least 0.05 Tesla and its main electromagnetic field can be generated by layers of conductors instead of bundles. Certain electromagnet designs may be fabricated using non-metallic formers, such as fiberglass, and can be constructed to form a rigid object with the layers of conductors by fixing all together with an epoxy. The electromagnet may be configured to have two separated halves, which may be held apart by a fixation structure such as carbon fiber. The power supply for certain electromagnets herein may have current fluctuations, at frequencies of 180 Hz or above, of at least one part per ten thousand without requiring an additional current filter.

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 radio frequency coil is disclosed that is suitable for use with a magnetic resonance imaging apparatus. The radio frequency coil comprises first and second conductive loops connected electrically to each other by a plurality of conductive rungs. The conductive rungs each include a section that is relatively thin that will result in less attenuation to a radiation beam than other thicker sections of the rungs. Insulating regions are also disposed in areas of the radio frequency coil that are bound by adjacent rungs and the conductive loops. Portions of the insulating regions can be configured to provide a substantially similar amount of attenuation to the radiation beam as the relatively thin sections of the conductive rungs.

Abstract: Edema in tissue of a patient undergoing a course of radiation therapy or treatment can be estimated based on one or more MRI measurements used to measure changes in fluid content of various tissues. A correlation between observed changes in edema and one or more delivered fractions of radiation can be used to drive one or more clinical actions. Methods, systems, articles of manufacture, and the like are described.

Abstract: A radiofrequency receive coil assembly can include a first conductive loop and a second conductive loop electrically connected at a node. The first and second conductive loops can extend into a treatment beam region of the radio frequency receive coil assembly through which one or more beams of ionizing radiation pass. The first conductive loop and the second conductive loop can overlap each other to provide electromagnetic isolation and/or can use a common conductor combined with a shared capacitor to provide electromagnetic isolation, with the shared capacitor or other electrical components, as well as any conductive loop overlaps, being positioned outside of the treatment beam region. These features can, among other possible advantages, minimize and homogenize attenuation of the beams of ionizing radiation by the radiofrequency receive coil assembly.

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 system including a diagnostic-quality CT scanner for imaging a patient, the diagnostic-quality CT scanner having an imaging isocenter and a radiation therapy device positioned adjacent the diagnostic-quality CT scanner, the radiation therapy device including a gantry carrying a radiation therapy beam source and having a radiation therapy isocenter separate from the imaging isocenter of the diagnostic-quality CT scanner. The system including a couch configured to position the patient for imaging and for radiation therapy by translating the patient between the diagnostic quality CT scanner and the radiation therapy device.

Abstract: A radiofrequency receive coil assembly can include a first conductive loop and a second conductive loop electrically connected at a node. The first and second conductive loops can extend into a treatment beam region of the radio frequency receive coil assembly through which one or more beams of ionizing radiation pass. The first conductive loop and the second conductive loop can overlap each other to provide electromagnetic isolation and/or can use a common conductor combined with a shared capacitor to provide electromagnetic isolation, with the shared capacitor or other electrical components, as well as any conductive loop overlaps, being positioned outside of the treatment beam region. These features can, among other possible advantages, minimize and homogenize attenuation of the beams of ionizing radiation by the radiofrequency receive coil assembly.

Abstract: Edema in tissue of a patient undergoing a course of radiation therapy or treatment can be estimated based on one or more MRI measurements used to measure changes in fluid content of various tissues. A correlation between observed changes in edema and one or more delivered fractions of radiation can be used to drive one or more clinical actions. Methods, systems, articles of manufacture, and the like are described.

Abstract: A photon therapy delivery system can deliver radiation therapy to a patient via a photon beam. The system can utilize a controller configured to facilitate delivery of radiation therapy via a photon beam and also a particle beam. This can include receiving radiation therapy beam information for radiation therapy treatment of a patient utilizing the particle beam and photon beam. Also, patient magnetic resonance imaging (MRI) data can be received during the radiation therapy treatment. Utilizing the patient MRI data, real-time calculations of a location of dose deposition for the particle beam and for the photon beam can be determined taking into account interaction properties of soft tissues through which the particle beam passes.

Abstract: A radio frequency coil is disclosed that is suitable for use with a magnetic resonance imaging apparatus. The radio frequency coil comprises first and second conductive loops connected electrically to each other by a plurality of conductive rungs. The conductive rungs each include a section that is relatively thin that will result in less attenuation to a radiation beam than other thicker sections of the rungs. Insulating regions are also disposed in areas of the radio frequency coil that are bound by adjacent rungs and the conductive loops. Portions of the insulating regions can be configured to provide a substantially similar amount of attenuation to the radiation beam as the relatively thin sections of the conductive rungs.

Abstract: An ion chamber has a chamber having an interior volume. There is a first electrode and a second electrode in the chamber and separated by a gap. A collector electrode is positioned between the first electrode and the second electrode. The collector electrode is shaped to occlude a portion of the first electrode from the second electrode.

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: Magnetic resonance (MR) guided radiation therapy (MRgRT) enables control over the delivery of radiation based on patient motion indicated by MR imaging (MRI) images captured during radiation delivery. A method for MRgRT includes: simultaneously using one or more radiation therapy heads to deliver radiation and an MRI system to perform MRI; using a processor to determine whether one or more gates are triggered based on at least a portion of MRI images captured during the delivery of radiation; and in response to determining that one or more gates are triggered based on at least a portion of the MRI images captured during the delivery of radiation, suspending the delivery of radiation.

Abstract: A system including a diagnostic-quality CT scanner for imaging a patient, the diagnostic-quality CT scanner having an imaging isocenter and a radiation therapy device positioned adjacent the diagnostic-quality CT scanner, the radiation therapy device including a gantry carrying a radiation therapy beam source and having a radiation therapy isocenter separate from the imaging isocenter of the diagnostic-quality CT scanner. The system including a couch configured to position the patient for imaging and for radiation therapy by translating the patient between the diagnostic quality CT scanner and the radiation therapy device.

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: Magnetic resonance (MR) guided radiation therapy (MRgRT) enables control over the delivery of radiation based on patient motion indicated by MR imaging (MRI) images captured during radiation delivery. A method for MRgRT includes: simultaneously using one or more radiation therapy heads to deliver radiation and an MRI system to perform MRI; using a processor to determine whether one or more gates are triggered based on at least a portion of MRI images captured during the delivery of radiation; and in response to determining that one or more gates are triggered based on at least a portion of the MRI images captured during the delivery of radiation, suspending the delivery of radiation.

Abstract: Edema in tissue of a patient undergoing a course of radiation therapy or treatment can be estimated based on one or more MRI measurements used to measure changes in fluid content of various tissues. A correlation between observed changes in edema and one or more delivered fractions of radiation can be used to drive one or more clinical actions. Methods, systems, articles of manufacture, and the like are described.