Toshiba Medical Systems Corporation

Kabushiki Kaisha Toshiba

Canon Medical Systems Corporation

Kazuto Nogami

Yoshitomo Sakakura

Hidekazu Tanaka

Masateru Iwasa

Tomoyuki Yoshida

Fumitoshi Kojima

Kohei Adachi

Makoto Sato

Shigehide Kuhara

Satoshi Sugiura

Hiroshi Sugimoto

Koji Kitamura

Yutaka Kato

Shohei Takami

Yasutake Yasuhara

Toshiki Idemaru

Taketo Kawakami

Takashi Yanashima

Dai Yamashiro

A permanent current switch apparatus according to an embodiment is a permanent current switch apparatus electrically connected to a superconducting coil via a superconducting wire, the permanent current switch apparatus including a plurality of parallel structures with thermal permanent current switches connected in parallel, the thermal permanent current switches being capable of switching between conducting and interrupting an electric current flowing through the superconducting wire. The parallel structures are connected in series.

Permanent current switch apparatus and magnetic resonance imaging apparatus

A magnetic resonance imaging apparatus according to an embodiment includes a static field magnet, a gradient coil and a shim housing box. The static field magnet generates a static magnetic field in a space within a substantially cylindrical hollow. The gradient coil is provided inside the static field magnet and generates a gradient magnetic field. The shim housing box is capable of housing a metallic shim, the shim housing box being formed into a shape such that an attractive force of the static magnetic field applied to the shim housing box under magnetic excitation becomes smaller than a predetermined threshold.

Magnetic resonance imaging apparatus and gradient coil

According to one embodiment, a magnetic field adjustment implement for a magnetic resonance imaging apparatus includes a magnetic field adjustment unit and a placing unit. The magnetic field adjustment unit is configured to improve a uniformity of a static magnetic field formed by a magnet of the magnetic resonance imaging apparatus. The static magnetic field is formed under an influence of a circumstance in a shield room in which the magnet is placed. The magnetic field adjustment is placed outside the magnet. The placing unit is configured to place the magnetic field adjustment unit outside the magnet.

Magnetic resonance imaging apparatus, magnetic field adjustment implement for magnetic resonance imaging apparatus, magnetic resonance imaging method, and method of adjusting magnetic field for magnetic resonance imaging apparatus

According to one embodiment, a magnetic resonance imaging apparatus includes an imaging unit and a shield. The imaging unit is configured to perform magnetic resonance imaging of an object by transmitting a radio frequency signal from a radio frequency coil while magnetic fields are formed by a gradient coil and a superconducting magnet respectively. The shield is configured to form a gradient magnetic field for the magnetic resonance imaging with the gradient coil and to prevent ingress of heat into the superconducting magnet.

Magnetic resonance imaging apparatus and magnet for magnetic resonance imaging apparatus

A magnetic resonance diagnostic apparatus is configured in such a manner that: a high-frequency transmission coil transmits a high-frequency electromagnetic wave at a magnetic resonance frequency to an examined subject; a heating coil performs a heating process by radiating a high-frequency electromagnetic wave onto the examined subject at a frequency different from the magnetic resonance frequency; based on a magnetic resonance signal, a measuring unit measures the temperature of the examined subject changing due to the high-frequency electromagnetic wave radiated by the heating coil; and a control unit exercises control so that the measuring unit measures the temperature while the heating coil is performing the heating process, by ensuring that the transmission of the high-frequency electromagnetic wave by the high-frequency transmission coil and the radiation of the high-frequency electromagnetic wave by the heating coil are performed in parallel.

Magnetic resonance diagnostic apparatus

According to one embodiment, a magnetic resonance imaging apparatus includes a static magnetic-field generating unit, a gradient magnetic-field generating unit, a plurality of metal shim plates in a plate shape, and a shim holding unit. The metal shim plates adjust uniformity of the static magnetic field. The shim holding unit holds the metal shim plates in a layered state. Each of the metal shim plates includes a convex having a certain angle at a certain position, and the metal shim plates are layered such that the convex of each one metal shim plate comes into contact with a back of the bent convex of another metal shim plate.

Magnetic resonance imaging apparatus and shimming apparatus with convex to concave layered stacking of shim plates

A feedforward control unit predicts the maximum value of the temperature of a gradient coil based on a power duty and a scan time of a pulse sequence, and a present temperature of the gradient coil. When the maximum value exceeds a predetermined upper limit, the feedforward control unit then instructs a temperature adjusting unit to start a water circulation in a chiller at the start of a prescan, and the temperature adjusting unit starts the water circulation based on the instruction.

Magnetic resonance imaging apparatus and gradient coil cooling control method

A magnetic resonance imaging apparatus includes a static magnetic field generating unit, a main coil (gradient magnetic coil), a radio frequency coil, and a shimming structure unit. The shimming structure unit includes first iron shims and second iron shims. The first iron shims are disposed between the main coil and a shield coil of the gradient magnetic coil and disposed in a central axial center of the static magnetic field generating unit. The second iron shims are disposed on an outer side of the main coil and the shield coil and disposed on a central axial end of the static magnetic field generating unit.

Growing community of inventors

Nasushiobara, Japan

Kazuto Nogami