A gradient coil system has a cylindrical section in a central region, which contains no conductor elements and has a maximum outer radius that is larger than a minimum inner radius of conductor elements of a main gradient coil. An outer radius of this cylindrical section is only insubstantially smaller or equal in size to a minimum inner radius of a shielding coil in this axial range. The free space in the center of the gradient coil system is used to insert a passive RF shield, whose radius in a central region becomes larger over a certain length than its radius in outer regions. The RF shield is constructed from at least three partial sections, which are electrically interconnected. The actively shielded gradient coil system maximizes the volume of the RF region without loss of gradient coil system performance.

A coil apparatus and methods for magnetic resonance imaging involving a wire winding, the wire winding having at least one of: a hollow cross-section wire and a solid cross-section wire, the solid cross-section wire having at least one of: a solid small cross-section wire and a solid large cross-section wire, the solid large cross-section wire having a thickness greater than that of the solid small cross-section wire, and the solid small cross-section wire disposed in one of adjacent and proximate at least one of the hollow cross-section wire and the solid large cross-section wire, whereby at least one of current density, winding density, and heat extraction are increasable.

According to some aspects, a laminate panel is provided. The laminate panel comprises at least one laminate layer including at least one non-conductive layer and at least one conductive layer patterned to form at least a portion of a B.sub.0 coil configured to contribute to a B.sub.0 field suitable for use in low-field magnetic resonance imaging (MRI).

A magnetic resonance apparatus comprising: a magnetic system configured to provide a magnetic field throughout at least a portion of a cavity, the magnetic field based on magnetic-system-control-data; a transmitter antenna disposed at least partly within the cavity and configured to transmit radio-frequency-transmitted-signalling based on transmitter-control-data; and a receiver antenna disposed at least partly within the cavity and configured to receive radio-frequency-received-signalling representative of magnetic resonance interactions of at least one object, disposed within the portion of the cavity, with the magnetic field and the radio-frequency-transmitted-signalling; wherein, at least one of the transmitter antenna, the receiver antenna and the magnetic system comprises a plasma antenna, and the magnetic resonance imaging apparatus is configured to provide received-data representative of the radio-frequency-received-signalling, the received-data in combination with the magnetic-system-control-data and the transmitter-control-data suitable for providing magnetic resonance imaging and/or magnetic resonance spectroscopy of the at least one object.

According to some aspects, a portable magnetic resonance imaging system is provided, comprising a magnetics system having a plurality of magnetics components configured to produce magnetic fields for performing magnetic resonance imaging. The magnetics system comprises a permanent B.sub.0 magnet configured to produce a B.sub.0 field for the magnetic resonance imaging system, and a plurality of gradient coils configured to, when operated, generate magnetic fields to provide spatial encoding of emitted magnetic resonance signals, a power system comprising one or more power components configured to provide power to the magnetics system to operate the magnetic resonance imaging system to perform image acquisition, and a base that supports the magnetics system and houses the power system, the base comprising at least one conveyance mechanism allowing the portable magnetic resonance imaging system to be transported to different locations. According to some aspects, the base has a maximum horizontal dimension of less than or equal to approximately 50 inches. According to some aspects, the portable magnetic resonance imaging system weighs less than 1,500 pounds. According to some aspects, the portable magnetic resonance imaging system has a 5-Gauss line that has a maximum dimension of less than or equal to five feet.

Systems and methods for designing and manufacturing electromagnetic coils for use with a magnetic resonance imaging (“MRI”) system are described. More particularly, described here are methods for designing and manufacturing gradient coils for producing magnetic field gradients with greater peripheral nerve stimulation (“PNS”) thresholds relative to conventional gradient coils. The gradient coil design is constrained using an oracle penalty that is computed to account for a PNS requirement for the coil. In other applications, the oracle penalty can be used to optimize driving patterns for an electromagnetic stimulation system, such that a target PNS requirement is achieved.

A magnetic resonance (MR) local coil, a magnetic resonance apparatus with an MR local coil, and a method for producing an MR local coil are provided. The MR local coil includes an outer casing, an antenna structure, and a frame for accommodating the antenna structure. The outer casing is embodied in a flexible manner and surrounds an inner area. The frame is embodied in a rigid manner, at least in regions, and is connected to the outer casing in a fixed manner. The antenna structure is arranged in the inner area of the outer casing and is held in position by the frame.

A magnetic resonance (MR) local coil, a magnetic resonance apparatus with an MR local coil, and a method for producing an MR local coil are provided. The MR local coil includes an outer casing, an antenna structure, and a frame for accommodating the antenna structure. The outer casing is embodied in a flexible manner and surrounds an inner area. The frame is embodied in a rigid manner, at least in regions, and is connected to the outer casing in a fixed manner. The antenna structure is arranged in the inner area of the outer casing and is held in position by the frame.

Magnetic resonance imaging (MRI) systems and methods, involving: a main magnet configured to generate a magnet field for MRI; a transmit radio frequency (RF) coil assembly configured to transmit an RF pulse into a portion of a subject; an RF coil assembly configured to, in response to the an RF pulse, receive MR signals emitted from the portion of the subject; and a gradient coil assembly having coil windings arranged in a radial layer and a first set of electrical connectors embedded in the radial layer to reduce a radial extent occupied by the gradient coil assembly, an electrical connector in the first set of electrical connectors configured to cross over a portion of the coil windings in the radial layer, the first set of electrical connectors configured to drive the coil windings with a current sufficient to generate a perturbation in the magnet field such that the MR signals encode an MR image based on the perturbation, and the radial layer having a depressed area configured to radially constrain the electrical connector.

An apparatus for fabricating non-planar coils includes a rotating table driven by a first motor; a wire approach height adjustment arm driven by a second motor; and a synchronization module configured such that a wire traversing from the height adjustment arm to a bobbin on the rotating table passes into a non-planar groove cut in the bobbin without damaging the wire. Performing magnetic resonance (MR) measurements includes a plurality of coil units configured for generating a gradient or shim magnetic field. The coil unit includes a plurality of coil windings, and each coil winding is separated longitudinally from an adjacent coil winding. A single pair of electrically conducting leads is configured to cause current to flow through all of the plurality of coil windings in the coil unit. Techniques include methods to fabricate and operate the apparatus.