Abstract: A magnet structure includes a permanent magnet assembly and first and second pole assemblies. The permanent magnet assembly includes an enclosure having an open portion and a magnetic mass disposed within the enclosure. Each of the first and second pole assemblies includes a base portion, disposed within the enclosure, a pole extension, extending from the first base portion outward from the enclosure, and a pole on the pole extension, having a pole face. The first and second pole assemblies are arranged such that the pole face of the first pole opposes the pole face of the second pole.

Abstract: A magnetic resonance imaging magnet includes a ferromagnetic frame. A pair of generally toroidal superconducting coil units overlie interfaces of side walls incorporated in the frame. Each coil unit may include a vessel having hollow support extensions extending into recesses in the side walls. The coil units may further include elongated, low-thermal conductance supports disposed within the support extensions. The frame may include pole stems projecting inwardly from the side walls, and the coils may be disposed in close proximity to the pole stems. Cryocoolers may be mounted to the frame so that the cryocoolers are substantially mechanically isolated from the coils of the coil units, but are in thermal communication therewith. The cryocooler mountings may be arranged for convenient servicing and installation of the cryocoolers.

Abstract: A magnet structure produces a field within a magnet gap. The field is provided at least in part by a pair of permanent magnets that are fixed in place by a frame. The frame fixes a magnet assembly that is adapted to hold the magnetic material composing the permanent magnets, such that the quantity of the magnetic material can be adjusted to suit the particular application. The magnetic material can be provided in the form of discrete magnetic elements, such as magnetic “bricks”. The frame also functions as the flux collector and return. Accordingly, the general geometry of the magnet structure is fixed, and the amount of magnetic material, and therefore the magnetic field strength, is adjustable.

Abstract: Magnet assembly for use in medical magnetic resonance imaging includes means for increasing flux generation in the gap region to provide the capability of scanning smaller volume regions of a patient at increased levels of scanning resolution. The means for increasing flux generation is mechanical or electromagnetic, is coupled to each of the polar regions and maintains the gap region sufficiently large and unobstructed to allow for access to the patient by several persons during scanning. Tapered outer walls of the polar region proximate the gap region further enhance accessibility to the patient during scanning.

Abstract: A magnet structure produces a field within a magnet gap. The field is provided at least in part by a pair of permanent magnets that are fixed in place by a frame. The frame fixes a magnet assembly that is adapted to hold the magnetic material composing the permanent magnets, such that the quantity of the magnetic material can be adjusted to suit the particular application. The magnetic material can be provided in the form of discrete magnetic elements, such as magnetic “bricks”. The frame also functions as the flux collector and return. Accordingly, the general geometry of the magnet structure is fixed, and the amount of magnetic material, and therefore the magnetic field strength, is adjustable.

Abstract: A magnet structure produces a field within a magnet gap. The field is provided at least in part by a pair of permanent magnets that are fixed in place by a frame. The frame fixes a magnet assembly that is adapted to hold the magnetic material composing the permanent magnets, such that the quantity of the magnetic material can be adjusted to suit the particular application. The magnetic material can be provided in the form of discrete magnetic elements, such as magnetic “bricks”. The frame also functions as the flux collector and return. Accordingly, the general geometry of the magnet structure is fixed, and the amount of magnetic material, and therefore the magnetic field strength, is adjustable.

Abstract: In one aspect, a magnet comprising a pair of pole supports spaced apart from one another and extending in a generally horizontal direction. The magnet includes a pair of flux return members extending between the pole supports so as to define a frame, each of the flux return members including a first columnar section that extends parallel to the polar axis and a second columnar section that extends perpendicular to the polar axis and projects towards the pole. In another aspect, a magnetic resonance imaging system comprises a ferromagnetic frame that is operative to support an upper pole member and a lower pole member along a vertical polar axis such that a gap is defined between the upper and lower pole members and an access floor that is isolated from the ferromagnetic frame and pole members for providing access to the gap.

Abstract: A magnet structure produces a field within a magnet gap. The field is provided at least in part by a pair of permanent magnets that are fixed in place by a frame. The frame fixes a magnet assembly that is adapted to hold the magnetic material composing the permanent magnets, such that the quantity of the magnetic material can be adjusted to suit the particular application. The magnetic material can be provided in the form of discrete magnetic elements, such as magnetic “bricks”. The frame also functions as the flux collector and return. Accordingly, the general geometry of the magnet structure is fixed, and the amount of magnetic material, and therefore the magnetic field strength, is adjustable.

Abstract: Magnet assembly for use in medical magnetic resonance imaging includes means for increasing flux generation in the gap region to provide the capability of scanning smaller volume regions of a patient at increased levels of scanning resolution. The means for increasing flux generation is mechanical or electromagnetic, is coupled to each of the polar regions and maintains the gap region sufficiently large and unobstructed to allow for access to the patient by several persons during scanning. Tapered outer walls of the polar region proximate the gap region further enhance accessibility to the patient during scanning.

Abstract: A magnet structure produces a field within a magnet gap. The field is provided at least in part by a pair of permanent magnets that are fixed in place by a frame. The frame fixes a magnet assembly that is adapted to hold the magnetic material composing the permanent magnets, such that the quantity of the magnetic material can be adjusted to suit the particular application. The magnetic material can be provided in the form of discrete magnetic elements, such as magnetic “bricks”. The frame also functions as the flux collector and return. Accordingly, the general geometry of the magnet structure is fixed, and the amount of magnetic material, and therefore the magnetic field strength, is adjustable.

Abstract: Magnet assembly for use in medical magnetic resonance imaging includes means for increasing flux generation in the gap region to provide the capability of scanning smaller volume regions of a patient at increased levels of scanning resolution. The means for increasing flux generation is mechanical or electromagnetic, is coupled to each of the polar regions and maintains the gap region sufficiently large and unobstructed to allow for access to the patient by several persons during scanning. Tapered outer walls of the polar region proximate the gap region further enhance accessibility to the patient during scanning.

Abstract: An apparatus and method that tests an NMR system, including MRI scanners, by taking H-B measurements for the apparatus at any stage during the manufacture thereof, to thereby detect any defects of the NMR system at any point during the manufacture thereof.

Abstract: A magnetic resonance imaging (MRI) magnet in combination with a mobile patient-positioning device, including a patient support and a method of using same for positioning patients for MRI scanning. The patient support is rotatable through a range of orientations from a horizontal to a vertical position, including being lockable at any oblique angle with respect to the horizontal. The patient disposed on the patient-positioning device in a predetermined orientation can then be moved horizontally into and out of a patient-receiving space in the MRI magnet at the predetermined angle or orientation. A preferred embodiment includes a plurality of patient-positioning devices in which a series of patients can be placed in a ready state while one patient is within the patient-receiving space. As an alternative embodiment, the patient may be moved vertically into position for MRI scanning by way of an elevator which is actuatable from the floor below the patient receiving space.

Abstract: A magnetic resonance imaging (MRI) magnet in combination with a mobile patient-positioning device, including a patient support and a method of using same for positioning patients for MRI scanning. The patient support is rotatable through a range of orientations. The patient disposed on the patient-positioning device in a predetermined orientation can then be moved horizontally into and out of a patient-receiving space in the MRI magnet at the predetermined angle or orientation. A preferred embodiment includes a plurality of patient-positioning devices in which a series of patients can be placed in a ready state while one patient is within the patient-receiving space. As an alternative embodiment, the patient may be moved vertically into position for MRI scanning by way of an elevator which is actuatable from the floor below the patient receiving space. This elevator also may be used in combination with the patient-positioning device.

Abstract: A magnetic resonance imaging (MRI) magnet in combination with a mobile patient-positioning device, including a patient support and a method of using same for positioning patients for MRI scanning. The patient support is rotatable through a range of orientations from a horizontal to a vertical position, including being lockable at any oblique angle with respect to the horizontal. The patient disposed on the patient-positioning device in a predetermined orientation can then be moved horizontally into and out of a patient-receiving space in the MRI magnet at the predetermined angle or orientation. A preferred embodiment includes a plurality of patient-positioning devices in which a series of patients can be placed in a ready state while one patient is within the patient-receiving space. As an alternative embodiment, the patient may be moved vertically into position for MRI scanning by way of an elevator which is actuatable from the floor below the patient receiving space.

Abstract: A magnetic resonance imaging (MRI) magnet in combination with a mobile patient-positioning device, including a patient support and a method of using same for positioning patients for MRI scanning. The patient support is rotatable through a range of orientations. The patient disposed on the patient-positioning device in a predetermined orientation can then be moved horizontally into and out of a patient-receiving space in the MRI magnet at the predetermined angle or orientation. A preferred embodiment includes a plurality of patient-positioning devices in which a series of patients can be placed in a ready state while one patient is within the patient-receiving space. As an alternative embodiment, the patient may be moved vertically into position for MRI scanning by way of an elevator which is actuatable from the floor below the patient receiving space. This elevator also may be used in combination with the patient-positioning device.

Abstract: Magnet assembly for use in medical magnetic resonance imaging includes means for increasing flux generation in the gap region to provide the capability of scanning smaller volume regions of a patient at increased levels of scanning resolution. The means for increasing flux generation is mechanical or electromagnetic, is coupled to each of the polar regions and maintains the gap region sufficiently large and unobstructed to allow for access to the patient by several persons during scanning. Tapered outer walls of the polar region proximate the gap region further enhance accessibility to the patient during scanning.

Abstract: A magnetic imager 10 includes a generator 18 for practicing a method of applying a background magnetic field over a concealed object, with the object being effective to locally perturb the background field. The imager 10 also includes a sensor 20 for measuring perturbations of the background field to detect the object. In one embodiment, the background field is applied quasi-statically. And, the magnitude or rate of change of the perturbations may be measured for determining location, size, and/or condition of the object.