A split cylindrical superconducting magnet system including two half magnets, each half magnet comprising superconducting magnet coils retained in an outer vacuum chamber, having a thermal radiation shield located between the magnet coils and the outer vacuum chamber, wherein the thermal radiation shield is shaped such that the axial spacing between thermal radiation shields of respective half magnets is greater at their internal diameter than at their outer diameter.

Improved magnetic resonance imaging systems, methods and software are described including a low field strength main magnet, a gradient coil assembly, an RF coil system, and a control system configured for the acquisition and processing of magnetic resonance imaging data from a patient while utilizing a sparse sampling imaging technique.

Improved magnetic resonance imaging systems, methods and software are described including a low field strength main magnet, a gradient coil assembly, an RF coil system, and a control system configured for the acquisition and processing of magnetic resonance imaging data from a patient while utilizing a sparse sampling imaging technique.

A magnetic resonance imaging device may include a field generator configured to provide a magnetic field in an imaging volume of the magnetic resonance imaging device. The field generator may include at least one magnet that confines the imaging volume in at least one spatial direction. The at least one magnet may be curved in such a way that a perpendicular distance between a line oriented along a direction of access to the imaging volume and a surface directed towards the imaging volume of the at least one magnet varies in the direction of access to the imaging volume.

In some aspects, a magnetic system for use in a low-field MRI system. The magnetic system comprises at least one electromagnet configured to, when operated, generate a magnetic field to contribute to a B.sub.0 field for the low-field MRI system, and at least one permanent magnet to produce a magnetic field to contribute to the B.sub.0 field.

A method of producing a permanent magnet shim configured to improve a profile of a B.sub.0 magnetic field produced by a B.sub.0 magnet is provided. The method comprises determining deviation of the B.sub.0 magnetic field from a desired B.sub.0 magnetic field, determining a magnetic pattern that, when applied to magnetic material, produces a corrective magnetic field that corrects for at least some of the determined deviation, and applying the magnetic pattern to the magnetic material to produce the permanent magnet shim. According to some aspects, a permanent magnet shim for improving a profile of a B.sub.0 magnetic field produced by a B.sub.0 magnet is provided. The permanent magnet shim comprises magnetic material having a predetermined magnetic pattern applied thereto that produces a corrective magnetic field to improve the profile of the B.sub.0 magnetic field.

Systems and methods involving: a housing having a bore in which a subject to be imaged is placed; a main magnet configured to generate a volume of magnetic field within the bore, the volume of magnetic field having inhomogeneity below a defined threshold; gradient coils configured to linearly vary the volume of magnetic field as a function of spatial location; pulse-generating coils configured to generate and apply radio frequency (RF) pulses to the volume of magnetic field in sequence to scan the portion of the subject; shim gradient coils configured to perturb a spatial distribution of the linearly varying volume of magnetic field; and a control unit configured to operate the gradient coils, pulse-generating coils, and shim gradient coils such that only the user-defined region within the volume of magnetic field is imaged.

Improved magnetic resonance imaging systems, methods and software are described including a low field strength main magnet, a gradient coil assembly, an RF coil system, and a control system configured for the acquisition and processing of magnetic resonance imaging data from a patient while utilizing a sparse sampling imaging technique.

Disclosed embodiments provide an apparatus and method for imaging breast tissue of a subject, wherein a subject is positioned on a structure so that at least a portion of the subject's body is supported by the structure, magnetic resonance imaging is performed on the portion of the subject's body using an MRI system including a plurality of MRI coils positioned in proximity to the structure, wherein, while the portion of the subject's body is positioned upon the structure, breast tissue of the subject's body is compressed in the proximity of plurality of MRI coils.

A system including a magnetic resonance imaging system having a magnet and first and second sidewalls positioned on opposite sides of an imaging field of the magnet, and a subject support configured to support a subject that is positioned in an upright position. The system may be capable of imaging a target anatomy of the subject while the subject is in the upright position, and may further include a motor for translating the subject support between first and second positions within and outside of the imaging field of the magnet, respectively. The subject support may include a seat on which the subject may sit facing the subject support, such that the subject's back can be operated on and imaged while the subject is in an upright position.