Abstract: A gradient coil comprising: a pair of gradient coil units disposed so as to enclose a gradient axis, each gradient coil unit including: a gradient coil substrate with a primary coil section, a shield coil section, and first and second return path sections, the primary coil section disposed between the gradient axis and the shield coil section, the primary coil section configured to produce a magnetic gradient field at the gradient axis when conducting an electrical current; the first return path section foldably connected between the primary coil section and the shield coil section, and the second return path section foldably connected between the shield coil section and the primary coil section such that the gradient coil substrate forms a cylindrical surface having a longitudinal axis substantially aligned with the gradient axis; and a plurality of substantially parallel conductive paths disposed across the cylindrical surface in a direction transverse to the gradient axis.

Abstract: A transverse gradient coil for an MRI system is provided. The transverse gradient coil comprises a first coil layer; and an insulation layer made of thermoplastic insulation resin which has a thermal conductivity greater than 1.5 W/m·K, the insulation layer having one side bonded to the first coil layer. A method for manufacturing the transverse gradient coil by injection molding or compression molding is also provided.

Abstract: A gradient coil comprising: a pair of gradient coil units disposed so as to enclose a gradient axis, each gradient coil unit including: a gradient coil substrate with a primary coil section, a shield coil section, and first and second return path sections, the primary coil section disposed between the gradient axis and the shield coil section, the primary coil section configured to produce a magnetic gradient field at the gradient axis when conducting an electrical current; the first return path section foldably connected between the primary coil section and the shield coil section, and the second return path section foldably connected between the shield coil section and the primary coil section such that the gradient coil substrate forms a cylindrical surface having a longitudinal axis substantially aligned with the gradient axis; and a plurality of substantially parallel conductive paths disposed across the cylindrical surface in a direction transverse to the gradient axis.

Abstract: A transverse gradient coil for an MRI system is provided. The transverse gradient coil comprises a first coil layer; and an insulation layer made of thermoplastic insulation resin which has a thermal conductivity greater than 1.5 W/m·K, the insulation layer having one side bonded to the first coil layer. A method for manufacturing the transverse gradient coil by injection molding or compression molding is also provided.

Abstract: Provided is an apparatus and method for automated hyperpolarization of samples for use as an imaging agent comprising a sample box, an airlock chamber configured to receive a sample from the sample box, a cryogenic chamber, a guide channel to transport samples from the airlock chamber to the cryogenic chamber, a heater and pressure module coupled to the sample box, an insertion and retraction device to transport samples through the guide channel to and from the cryogenic chamber, a dissolution module coupled to the sample box, and a controller to regulate hyperpolarization of the samples by controlling one or more of position, sequencing, temperature, pressure, and dissolution of the samples within the apparatus. Also provided is a machine-readable medium comprising instruction which, when executed by a controller, causes a hyperpolarization apparatus to perform the steps of hyperpolarization of a sample.

Abstract: A permanent magnet assembly for an imaging apparatus having a permanent magnet body having a first surface and a stepped second surface which is adapted to face an imaging volume of the imaging apparatus, wherein the stepped second surface contains at least four steps.

Abstract: A CT collimator includes a first radiation absorbent lamination having a plurality of apertures formed therethrough. Each aperture formed through the first radiation absorbent lamination is aligned with a respective axis formed between a corresponding pixellating element and an x-ray emission source. The collimator includes a second radiation absorbent lamination having a plurality of apertures formed therethrough, each aperture formed through the second radiation absorbent lamination aligned with the respective axis formed between a corresponding pixellating element and the x-ray emission source. A spacer is positioned between the first and second radiation absorbent laminations.

Abstract: A Magnetic Resonance Imaging (MRI) system having a vacuum vessel positioned about an imaging volume, one or more high temperature superconducting coils positioned within the vacuum vessel, and a cryocooler coupled to the vacuum vessel to operate the superconducting coil at a temperature above 10 K. At least one gradient coil is positioned between an imaging volume and the superconducting coil without any thermal shielding interposed between the gradient coil and the superconducting coil. A method of forming an MRI system includes forming at least one winding of the main field generating coils with high temperature superconducting material, positioning the winding in a vessel for receiving cryogenic fluid, and positioning a gradient coil between the imaging volume and the winding without placing a thermal radiation shield between the gradient coil and the winding.

Abstract: Disclosed herein is method for making a wire comprising contacting a first end of a first superconducting wire with a second end of a second superconducting wire, wherein the superconducting wire comprises a superconducting filament having a superconducting composition comprising magnesium diboride; heating the first end of the first superconducting wire with the second end of the second superconducting wire at a point to form a joint, wherein the superconducting filament having the superconducting composition is in continuous electrical contact with any other part of the superconducting filament after the formation of the joint.

Abstract: A permanent magnet assembly comprising a fixed permanent magnet body and a movable permanent magnet body which is movable relative to the fixed permanent magnet body.

Abstract: A method for shimming a magnetic field of a magnet in a volume of interest, utilizing ferromagnetic pellets for shimming. The pellets are positioned in a nonmagnetic holder having a predetermined number of pellet holes. The method includes measuring the magnetic field of a magnet in a plurality of locations within the volume of interest, determining a nominal passive shimming mass to compensate the measured magnetic field to approximate a desired magnetic field within the volume of interest; and placing a combination of ferromagnetic pellets from a selection of full strength pellets, nearly full strength pellets, and low strength pellets in the pellet holes to approximate the nominal passive shimming mass.

Abstract: A method for graphical visualization of a measured magnetic field on an imaging volume of a MRI magnet includes providing data values measured at selected points of the measured magnetic field, converting each of the data values to a visualizable value based on where the data value lies within a predetermined range of data values and thus within a range of visualizable values corresponding to the range of data values, and plotting each visualizable value corresponding to each data value at a position on a grid corresponding to the position of the selected point of the measured magnetic field such that the visualizable values once plotted on the grid provide a graphical visualization of the condition of the measured magnetic field.

Abstract: A pole piece for use in an open magnet includes a magnetizable body of generally cylindrical shape and made of a ferromagnetic material with a plurality of concentrically-arranged, annular-shaped, radially spaced-apart grooves formed in the inner surface of the pole piece. A plurality of annular-shaped, electrically conductive coils are disposed within the grooves. The pole piece with recessed shielding coils is situated within a cryogenic vessel to maintain the pole pieces at a uniform cryogenic temperature. The result is an open magnet structure which provides a highly uniform, high field, open field of view for MRI with a well-contained stray field.

Abstract: A pole piece for use in an open magnet includes a magnetizable body of generally cylindrical shape and made of a ferromagnetic material with a plurality of concentrically-arranged, annular-shaped, radially spaced-apart grooves formed in the inner surface of the pole piece. A plurality of annular-shaped, electrically conductive coils are disposed within the grooves. The pole piece with recessed shielding coils is situated within a cryogenic vessel to maintain the pole pieces at a uniform cryogenic temperature. The result is an open magnet structure which provides a highly uniform, high field, open field of view for MRI with a well-contained stray field.

Abstract: A low noise imaging apparatus for producing Magnetic Resonance (MR) images of a subject and for substantially minimizing acoustic noise generated during imaging is provided. The imaging apparatus comprises a magnet assembly, a gradient coil assembly, and a rf coil assembly, wherein at least one of the magnet assembly, the gradient coil assembly and the rf coil assembly are configured to reduce the generation and transmission of acoustic noise.

Abstract: A method for graphical visualization of a measured magnetic field on an imaging volume of a MRI magnet includes providing data values measured at selected points of the measured magnetic field, converting each of the data values to a visualizable value based on where the data value lies within a predetermined range of data values and thus within a range of visualizable values corresponding to the range of data values, and plotting each visualizable value corresponding to each data value at a position on a grid corresponding to the position of the selected point of the measured magnetic field such that the visualizable values once plotted on the grid provide a graphical visualization of the condition of the measured magnetic field.

Abstract: An open magnet useful in magnetic resonance imaging (MRI) applications. The magnet has two spaced-apart assemblies. Each assembly has a shielding coil located longitudinally outward from a main coil, a magnetizable member not carrying an electric current and spaced apart from and proximate the main and shielding coils, and a magnetizable pole piece spaced apart from the magnetizable member: The method of the invention generates a magnetic field in a first area between the two assemblies while shielding a second area not between the two assemblies from a stray magnetic field by creating the previously-described open magnet.

Abstract: A superconductive magnet includes a superconductive coil assembly having a cryogenic vessel, a thermal shield enclosing the cryogenic vessel, and a vacuum enclosure enclosing the thermal shield. The cryogenic vessel, thermal shield and vacuum vessel have annular shells radially spaced apart from one another with reference to a common longitudinal axis and coaxially aligned with the common longitudinal axis. The magnet also includes a tube suspension assembly having a plurality of tubes located between respective ones of the cryogenic vessel, thermal shield and vacuum enclosure. The tubes are axially overlapped and are interconnected with one another and with the cryogenic vessel, thermal shield and vacuum enclosure. One tube has an end forming a sliding joint with the cryogenic vessel that allows both radial and axial movement of the cryogenic vessel relative to the thermal shield and vacuum enclosure during cooldown of the cryogenic vessel from ambient to cryogenic temperatures.

Abstract: An open magnet useful in magnetic resonance imaging (MRI) applications. The magnet has two spaced-apart assemblies. Each assembly has a shielding coil located longitudinally outward from a main coil, a magnetizable member not carrying an electric current and spaced apart from and proximate the main and shielding coils, and a magnetizable pole piece spaced apart from the magnetizable member: The method of the invention generates a magnetic field in a first area between the two assemblies while shielding a second area not between the two assemblies from a stray magnetic field by creating the previously-described open magnet.

Abstract: An open superconductive magnet useful in magnetic resonance imaging (MRI) applications. The magnet has two spaced apart assemblies, wherein each assembly has a magnetizable pole piece and a magnetizable ring radially spaced outwardly apart from, and at least partially longitudinally overlapping, the pole piece. A superconductive main coil is positioned radially between the pole piece and the ring. A superconductive shielding coil is positioned radially outward from the superconductive main coil and longitudinally outward from the longitudinally outer end of the ring.