With Homogeneity Control Patents (Class 324/320)
  • Publication number: 20130009643
    Abstract: A compact NMR analyzer for clinical examinations which is suitable for use at medical facilities is provided. An NMR analyzer for clinical examinations 1 for analyzing a sample including a liquid component extracted from a human body, includes: a solution feeding pump 6 that feeds a sample; a solution feeding pipe 18 that receives the sample fed from the solution feeding pump 6; a superconducting magnet 7 that encloses the solution feeding pipe 18 around an axis thereof; a helium container 9 that houses the superconducting magnet 7 and liquid helium 8; a vacuum container 12 that has a vacuum chamber and that houses the helium container 9 inside the vacuum chamber; heat shields 10 and 11 that cover the helium container 9 in the vacuum container 12; and a recondensing unit 3 that recondenses helium vaporized inside the helium container 9 and that cools the heat shields 10 and 11.
    Type: Application
    Filed: March 25, 2011
    Publication date: January 10, 2013
    Inventors: Takashi Miki, Yasuaki Terao
  • Publication number: 20120256631
    Abstract: An apparatus for determining the homogeneity of a fluid flow in a pipe, such as a reducing-agent flow in an exhaust-gas pipe of an internal combustion engine, including a transmitter arranged on a light-transmissive region of the pipe and a diametrically opposite detector. The transmitter and detector being coupled such that they are rotatable through an angle of 360° about a rotational axis which is located substantially in the axis of symmetry of the pipe. The transmitter and the detector are rotated through at least 360° about the rotational axis, thus capturing an intensity of the detected light over the rotation angle, and from this a homogeneity of the fluid flow is deduced.
    Type: Application
    Filed: April 5, 2012
    Publication date: October 11, 2012
    Applicant: ROBERT BOSCH GMBH
    Inventor: Christian Fuchs
  • Patent number: 8258903
    Abstract: A superconducting, actively shielded magnet has a first and second superconducting coil modules that generate a homogeneous magnetic field in a first direction in an operating volume of the magnet and that reduces the scatter magnetic field in an environment of the magnet. A third superconducting coil module is arranged in proximity to the first and second coil modules. The third coil module is fashioned to generate a compensation gradient field given occurrence of an interference gradient field in the environment so that the effect of the interference gradient field in the operating volume is reduced.
    Type: Grant
    Filed: January 15, 2010
    Date of Patent: September 4, 2012
    Assignee: Siemens Aktiengesellschaft
    Inventor: Guenter Schnur
  • Publication number: 20120202696
    Abstract: An open-structure magnetic assembly is adapted to generate a homogeneous magnetic field in an accessible space region, including a first and second independent source of magnetic field (10, 12), each generating a contribution to the resulting magnetic field. The first source includes a conducting or superconducting plate (20), carrying an unidirectional current flow (I) from an input side (22) to an output side (24) and at least one external current recirculating path (30) between the output side (24) and the input side (22) of the plate. The second source includes a volume of magnetized material or an arrangement of coils, arranged for generating a magnetic field component oriented according to the magnetic field generated by the first source (10), and whose intensity exhibits a gradient in a direction perpendicular to the conducting plate (20) adapted to compensate, in a region of interest, an opposite gradient in the magnetic field intensity generated by the first source (10).
    Type: Application
    Filed: October 18, 2010
    Publication date: August 9, 2012
    Applicant: Fondazione Istituto Italiano Di Tecnologia
    Inventors: Franco Bertora, Elisa Molinari, Andrea Viale, Giulio Sandini
  • Patent number: 8222985
    Abstract: A superconducting magnet configuration (4; 14) for generating a homogeneous magnetic field B0 in an examination volume (4b), has an interior radial superconducting main field coil (1) which is disposed rotationally symmetrically about an axis (z-axis) and an oppositely driven coaxial radially exterior superconducting shielding coil (2) is characterized in that the magnet configuration (4; 14) consists of the main field coil (1), the shielding coil (2), a ferromagnetic field formation device (3; 18) and a ferromagnetic shielding body (AK), wherein the ferromagnetic field formation device (3; 18) is located at the radially inside of the main field coil (1) and the ferromagnetic shielding device (AK) surrounds the main field coil (1) and the shielding coil (2) in a radial and axial direction, the main field coil (1) consisting of an unstructured solenoid coil or of several radially nested unstructured solenoid coils (15, 16) which are driven in the same direction, the axial extent Labs of the shielding coil (2)
    Type: Grant
    Filed: October 18, 2010
    Date of Patent: July 17, 2012
    Assignee: Bruker BioSpin GmbH
    Inventors: Gerald Neuberth, Michael Westphal
  • Patent number: 8154368
    Abstract: An actively shielded superconducting magnet configuration (M1; M2; M3; 14) for generating a homogeneous magnetic field B0 in a volume under investigation (4b) has a radially inner superconducting main field coil (1) which is disposed rotationally symmetrically about an axis (z axis) and a coaxial radially outer superconducting shielding coil (2) which is operated in an opposite direction. The magnet configuration consists of the main field coil, the shielding coil and a ferromagnetic field-shaping device (3; 18), wherein the ferromagnetic field-shaping device is disposed radially inside the main field coil. The main field coil consists of an unstructured solenoid coil or of several radially nested unstructured solenoid coils (15, 16) which are operated in the same direction. An extension Labs of the shielding coil in the axial direction is smaller than the extension Lhaupt of the main field coil in the axial direction.
    Type: Grant
    Filed: October 4, 2010
    Date of Patent: April 10, 2012
    Assignee: Bruker BioSpin GmbH
    Inventors: Michael Westphal, Gerald Neuberth
  • Patent number: 8116916
    Abstract: A method, system, and computer program product for selecting a transformer size for an industrial or commercial facility. A plurality of end-use connected load data for the facility is entered via a user interface into a memory of a computing system for determining facility load diversities. A base homogeneity is determined for the end-use connected load data. An initial facility diversity is determined based on the end-use connected loads and initial end-use diversities. A total facility diversity is determined based on the initial facility diversity, the base homogeneity, and a total connected load. An expected energy demand is determined based on the total facility diversity and a total connected load. The end-use diversity is adjusted for at least one end-use and a change in expected energy demand for the facility is allocated to each end-use. The transformer size is determined for a total expected energy demand and a total hours use for each connected load.
    Type: Grant
    Filed: October 20, 2009
    Date of Patent: February 14, 2012
    Assignee: Southern Company Services, Inc.
    Inventors: Jefferson G. Zeanah, Richard G. Huff
  • Publication number: 20120019248
    Abstract: When imaging for sensitivity distribution measurement is performed, a whole-body coil for both transmission and reception and a specified coil used for the present imaging are used as a reception coil, while being switched. The switching of the reception coil is performed by switching between the whole-body coil and the specified coil for each echo in the same encode step. An image created from the echo obtained by the specified coil is divided by an image created from the echo obtained by the whole-body coil to calculate the sensitivity distribution of the specified coil. The sets of data used for the calculation are almost simultaneously obtained, thus providing accurate sensitivity distribution with no influence derived from the movement of a subject. The sensitivity distribution is used to correct the image obtained by the present imaging. Alternatively, the sensitivity distribution is used for the folding operation of parallel imaging.
    Type: Application
    Filed: March 17, 2010
    Publication date: January 26, 2012
    Applicant: Hitachi Medical Corporation
    Inventor: Masayuki Nonaka
  • Patent number: 8035388
    Abstract: An apparatus for providing a sensitive volume for single-sided NMR includes: (i) at least one first permanent magnet for providing a first magnetic field at the sensitive volume; and (ii) at least one of the following means for superimposing at least one second magnetic field for homogenizing the first magnetic field in the sensitive volume: (A) at least one shim magnet, (B) at least one pair of shim magnets, and (C) at least one electrical conductor being connectable to an electric current source. The at least one second magnetic field is adjusted such that the magnetic field homogeneity in the sensitive volume is corresponding to a line width of hydrogen (1H) of less than 10 ppm.
    Type: Grant
    Filed: July 10, 2009
    Date of Patent: October 11, 2011
    Assignee: RWTH Aachen
    Inventors: Federico Casanova, Juan Francisco Perlo, Bernhard Blumich
  • Patent number: 8035387
    Abstract: One aspect of the present disclosure relates to a method or determining location(s) at which at least one magnetic article is to be positioned during a magnetic resonance imaging procedure of at least one subject. A magnetic field Bo is applied to a region that includes the at least one subject and does not include the at least one magnetic article. First magnetic resonance information about the region in response to the applied magnetic field BO is received. The first magnetic resonance information relates at least in part to one or more magnetic field inhomogeneities in the region. Based at least in part on the first magnetic resonance information, at least one first location proximate the at least one subject at which at least one paramagnetic article and/or diamagnetic article is to be positioned is determined, so as to at least partially compensate for the one or more magnetic field inhomogeneities.
    Type: Grant
    Filed: January 12, 2007
    Date of Patent: October 11, 2011
    Assignee: Yale University
    Inventors: Robin De Graaf, Kevin Koch
  • Patent number: 8013697
    Abstract: A method of manufacturing a solenoidal magnet structure, includes the step of providing a collapsible accurate mold in which to wind the coils winding wire into defined positions in the mold, placing a mechanical support structure over the coils so wound, impregnating the coils and the mechanical support structure with a thermosetting resin, allowing the thermosetting resin to harden, and collapsing the mold and removing the resultant solenoidal magnet structure formed by the resin impregnated coils and the mechanical support structure from the mold as a single solid piece.
    Type: Grant
    Filed: January 22, 2009
    Date of Patent: September 6, 2011
    Assignee: Siemens PLC
    Inventors: Simon James Calvert, Jonathan Noys, Adrian Mark Thomas
  • Patent number: 8008916
    Abstract: A magnetic resonance apparatus has a cylindrical gradient coil with an x-gradient coil and a y-gradient coil that are asymmetrical relative to the z-direction of a coordinate system, the z-direction extending along a longitudinal direction of a patient receptacle. Shim coils are provided that generate magnetic fields to homogenize the basic magnetic field, produced by a cylindrical basic field magnet, in an examination volume in the patient receptacle. At least some of the shim coils are asymmetrical relative to the z-direction to minimize coupling induction between the asymmetrical x-gradient coil and y-gradient coil and the asymmetrical shim coils.
    Type: Grant
    Filed: July 14, 2006
    Date of Patent: August 30, 2011
    Assignee: Siemens Aktiengesellschaft
    Inventors: Jörg Riegler, Axel vom Endt
  • Patent number: 7982566
    Abstract: A cryostat (1) with a magnet coil system including superconductors for the production of a magnet field B0 in a measuring volume (3) within a room temperature bore (2) of the cryostat has a plurality of radially nested solenoid-shaped coil sections (4, 5, 6) which surround the room temperature bore and which are electrically connected in series, at least one of which being an LTS section (5, 6) with a conventional low temperature superconductor (LTS) and at least one of which being an HTS section (4) including a high temperature superconductor (HTS), wherein the LTS section (5, 6) is located in a helium tank (9) of the cryostat (1) along with liquid helium at a helium temperature TL. The apparatus is characterized in that the HTS section (4) is disposed radially within the LTS section (5, 6) in a vacuum portion of the cryostat and is separated from the LTS section (5, 6) by the helium tank (9) wall (9a) facing the room temperature bore.
    Type: Grant
    Filed: March 7, 2007
    Date of Patent: July 19, 2011
    Assignee: Bruker BioSpin GmbH
    Inventor: Arne Kasten
  • Patent number: 7977946
    Abstract: A magnet assembly primarily for use in MRI Interventional applications having an array of four mam permanent magnets that are spaced-apart and arranged into a ring-like geometry with six easy-access openings The magnetization direction in each permanent magnet is anti-parallel to any other adjacent permanent magnet in the ?ng assembly while it is parallel to any other permanent magnet in the array that is oppositely located just as in a quadrupolar system Such an arrangement has the advantage of concentrating the magnetic field inside the nng enclosure while minimizing magnetic field generated outside Together, these four spatially spaced-apart permanent magnets create a very homogeneous and strong magnetic field in the central enclosure with two orthogonal access paths and one parallel access path to the enclosure Through one access pathway a patient can be inserted while through the other pathways a doctor can fully access the patient.
    Type: Grant
    Filed: June 25, 2007
    Date of Patent: July 12, 2011
    Inventors: Grum Teklemariam, Jianyu Lian
  • Publication number: 20110163750
    Abstract: In a method and apparatus for correcting the uniformity of a magnetic field, an active shim shell is placed in the magnetic field, a magnetic resonance image of the active shim shell obtained, and the placement position of the active shim shell is determined by analyzing the magnetic resonance image. The value of a shim current in the active shim shell is determined so as to meet the uniformity requirements of the magnetic field according to the placement position. The value of the shim current in said active shim shell is set to the determined value of the shim current.
    Type: Application
    Filed: December 29, 2010
    Publication date: July 7, 2011
    Inventors: Jin Jun Chen, Oliver Schreck
  • Patent number: 7928730
    Abstract: The electromagnet apparatuses generate a homogeneous magnetic field in a homogeneous magnetic field region by a pair of superconductive main coils for facing to each other; a pair of superconductive shielding coils for facing to each other and passing a current in a direction reverse to that of the main coils; and a pair of first ferromagnetic members for facing to each other, and the apparatuses further include a pair of second ferromagnetic members for facing to each other and be disposed in contact with or adjacent to an opposite side of the region side of the first ferromagnetic members, wherein the region is interposed between the main coils, between the shielding coils, between the first members whose outer periphery is a circle, and between the second members whose outer periphery is a circle whose diameter is larger than that of the circle of the first members.
    Type: Grant
    Filed: January 18, 2007
    Date of Patent: April 19, 2011
    Assignee: Hitachi, Ltd.
    Inventors: Manabu Aoki, Mitsushi Abe, Takeshi Nakayama, Masanori Takahashi
  • Patent number: 7928820
    Abstract: In a superconducting magnet, including a vacuum vessel, a coil vessel inside the vacuum vessel, and a superconducting coil inside the coil vessel for generating a magnetic field, has a magnetic member, disposed inside the vacuum vessel, supported with thermal insulation, for compensating the magnetic field; a heat exchange device disposed outside the vacuum vessel for supplying to or absorbing heat from the vacuum vessel; and thermal conducting members thermally connecting the heat exchange device via the vacuum vessel to the magnetic member. An MRI including the superconducting magnet is also disclosed.
    Type: Grant
    Filed: January 23, 2009
    Date of Patent: April 19, 2011
    Assignees: Hitachi, Ltd., Hitachi Medical Corporation
    Inventors: Tomoo Chiba, Hiroyuki Watanabe, Hirotaka Takeshima, Shigeki Tounosu, Mitsushi Abe, Hiroyuki Takeuchi
  • Patent number: 7924011
    Abstract: A cryocooler assembly includes a ferromagnetic shield and a moveable rare-earth regenerator for recondensing of a cooling liquid for cooling of a superconductive magnet of a magnetic resonance imaging apparatus. The ferromagnetic shield effectively provides depletion of a magnet field in the vicinity of the rare-earth regenerator and therefore on the one hand reduces the noise impact of the moving regenerator on the homogeneous magnetic field in the imaging volume of the MRI apparatus and on the other hand reduces the mechanical force exerted by the magnetic field on the rare-earth regenerator.
    Type: Grant
    Filed: June 21, 2006
    Date of Patent: April 12, 2011
    Assignee: Koninklijke Philips Electronics N.V.
    Inventor: Benjamin Hendricus Aarts
  • Publication number: 20110050229
    Abstract: In a method and device for compensating the insufficient homogeneity of a magnetic field in a magnetic resonance system, the spatial position and size of a basic magnetic field region and at least one additional magnetic field region in a field to be homogenized and determined. An optimization calculation is implemented on the basic magnetic field region and the at least one additional magnetic field region. A homogenized magnetic field at the main magnetic field region and the at least one additional magnetic field region is output according to the result of the optimization calculation.
    Type: Application
    Filed: August 24, 2010
    Publication date: March 3, 2011
    Inventors: Jin Jun Chen, Cheng Ni
  • Patent number: 7898257
    Abstract: An open yoke MRI apparatus has a set of permanent magnets arranged at the inner surfaces of the yoke and spaced apart from one another. A set of annular permanent magnets is included in each magnet arrangement, including a set with trapezoidal cross-sections to provide a more uniform field and to allow greater access to a patient placed within the magnetic field.
    Type: Grant
    Filed: August 2, 2007
    Date of Patent: March 1, 2011
    Assignee: Aspect Magnet Technologies, Ltd.
    Inventor: Ehud Katznelson
  • Patent number: 7898258
    Abstract: A superconducting magnet configuration (4; 14) for generating a homogeneous magnetic field B0 in an examination volume (4b), has an interior radial superconducting main field coil (1) which is disposed rotationally symmetrically about an axis (z-axis) and an oppositely driven coaxial radially exterior superconducting shielding coil (2) is characterized in that the magnet configuration (4; 14) consists of the main field coil (1), the shielding coil (2), and a ferromagnetic field formation device (3; 18), wherein the ferromagnetic field formation device (3; 18) is located at the radially inside of the main field coil (1), the main field coil (1) consisting of an unstructured solenoid coil or of several radially nested unstructured solenoid coils (15, 16) which are driven in the same direction, the axial extent Labs of the shielding coil (2) being smaller than the axial extent Lhaupt of the main field coil (1), wherein the axial magnetic field profile (5) generated by the main field coil (1) and the shielding co
    Type: Grant
    Filed: April 16, 2009
    Date of Patent: March 1, 2011
    Assignee: Bruker BioSpin GmbH
    Inventors: Gerald Neuberth, Michael Westphal
  • Patent number: 7889034
    Abstract: Disclosed is a method for designing a superconducting magnet for generating high magnetic fields with high uniformity for controlling a stray field to be within an allowable range and acquiring structural and magnetic stability by optimizing the arrangement of positions and shapes of coils configuring the superconducting magnet. Volumes of a main coil and a shielding coil are set to be variables, and the critical value of a wires related on the current and magnetic field, the heat transfer depth, and the quench strain are defined to be restriction conditions so that linear programming is applied to determine an initial shape of the shielding coil and division of the main coil based on the sum of total volumes, that is, an objective function. The initial shapes of the main coil and the shielding coil determined through the linear programming are revised and the shape of a shimming coil is determined by using non-linear programming based on the objective function.
    Type: Grant
    Filed: November 29, 2005
    Date of Patent: February 15, 2011
    Assignee: Korea Basic Science Institute
    Inventors: Byoung-Seob Lee, Dong-Lak Kim, Hyun-Sik Kim, Jong-Shin Yoo
  • Patent number: 7843196
    Abstract: A compact whole-body open circular magnet system for MRI purposes includes a protrusion overhanging the central homogeneous field region. The overhanging protrusion permits a reduction of the total magnet homogeneity requirements of the MRI system. Further reducing the radius of this protrusion increases access to a patient under examination but diminishes the homogeneity. Active shimming means incorporated in a gradient coil can regain the original homogeneity while maintaining increased patient access.
    Type: Grant
    Filed: September 17, 2004
    Date of Patent: November 30, 2010
    Assignee: XBO Medical Systems Co., Ltd.
    Inventors: Grum Teklemariam, Jianyu Lian
  • Publication number: 20100213940
    Abstract: A magnetic field gradient generating system for a NMR system, includes at least one set of gradient coils, preferably arranged according to three axes of a spatial referential system, and a controlled power supplying unit for the gradient coils, the power supplying unit including, for each gradient coil, a converter/amplifier module, the modules being fed with pulse sequences of digital gradient data provided as word streams by an adapted gradient data generator according to a pulse program, each arrangement of a gradient coil and a converter/amplifier module forming a gradient channel. The power supplying unit also includes an automatic blanking system which scans the gradient data words sent to the [converter/amplifier] modules and, according to sensed values, selectively delivers blanking signals to be applied to the modules in order to disable the power stages of their respective amplifiers connected to the gradient coils, when no current is to be fed to the coils.
    Type: Application
    Filed: February 23, 2010
    Publication date: August 26, 2010
    Applicant: BRUKER BIOSPIN
    Inventor: Ernest SCHAEFER
  • Patent number: 7759938
    Abstract: Apparatus and method for varying field strength in a magnetic resonance system while keeping a relatively uniform magnetic field distribution. In an embodiment, a two-pole, generally u-shaped magnet assembly generates a static and uniform magnetic field. The magnet assembly includes two facing magnet poles separated by an air gap. Holes may be formed with the magnet poles. The field control rods may be placed at a pre-determined distance into these holes and symmetrically or asymmetrically moved across each magnet poles in a controlled manner to change the magnetic field strength while keeping the uniform magnetic field distribution. Maximum magnetic field strength may occur when the rods are removed. Minimum magnetic field strength may occur when the rods are fully inserted.
    Type: Grant
    Filed: December 28, 2007
    Date of Patent: July 20, 2010
    Assignee: Morpho Detection, Inc.
    Inventors: Pablo J. Prado, Sankaran Kumar, Erik Edmund Magnuson
  • Patent number: 7755358
    Abstract: The method for determination of the design of the basic magnet of a magnetic resonance apparatus with at least one gradient coil system, the design of the basic magnet is determined by taking into consideration forces acting on the at least one gradient coil system that may lead to vibrations of the gradient coil system due to switching processes of the gradient coil system in the field of the basic magnet.
    Type: Grant
    Filed: May 28, 2008
    Date of Patent: July 13, 2010
    Assignee: Siemens Aktiengesellschaft
    Inventors: Peter Dietz, Graham Hutton, Andreas Krug, Axel Vom Endt
  • Patent number: 7755359
    Abstract: A magnetic resonance imaging apparatus capable of suppressing noise caused by vibration of a gradient magnetic field coil and improving image quality includes a large number of ferromagnetic shims disposed in a large number of holes formed in a shim tray, and vibration dampers disposed in holes formed in the shim tray to reduce noise generated by vibration of a gradient magnetic field generating coil.
    Type: Grant
    Filed: May 25, 2005
    Date of Patent: July 13, 2010
    Assignee: Hitachi Medical Corporation
    Inventors: Takashi Yamamizu, Shichihei Sakuragi, Hirotaka Takeshima, Hiroyuki Takeuchi
  • Patent number: 7741847
    Abstract: A magnetic resonance apparatus in which magnetic metal pieces are accommodated in an accommodation section so as to correct uniformity in a main magnetic field, includes an acquisition unit which acquires temperature information related to at least one of a temperature of the magnetic metal pieces accommodated in the accommodation section, a temperature of the accommodation section, and a temperature of a position in the vicinity of the accommodation section, and a temperature adjustment unit which adjusts the temperature of the magnetic metal pieces to a target temperature by preheating the magnetic metal pieces on the basis of the temperature information acquired by the acquisition unit.
    Type: Grant
    Filed: October 10, 2007
    Date of Patent: June 22, 2010
    Assignees: Kabushiki Kaisha Toshiba, Toshiba Medical Systems Corporation
    Inventors: Kazuto Nakabayashi, Masatoshi Hanawa
  • Patent number: 7719279
    Abstract: The present invention discloses a self-fastening cage of a magnetic resonance device (MRD) for providing a homogeneous, stable and uniform magnetic field therein, characterized by an outside shell comprising at least three flexi-jointed superimposed walls. The multi-streamed MRD comprising a cage including a closed magnetic circuit constructed from strong permanent magnets; and optionally a shimming mechanism selected from an array of active shim coils, passive shimming elements; a contained cavity within which the magnetic field strength is approximately uniform; and a plurality of conveyor belts, pipes or any transportation means by which a plurality of samples are introduced into the region of uniform magnetic field; such that magnetic resonance measurements are made on a plurality of samples within the region of uniform magnetic field. The invention depicts a cost effective method for obtaining a self-fastening cage.
    Type: Grant
    Filed: May 27, 2008
    Date of Patent: May 18, 2010
    Assignee: Aspect Magnet Technologies Ltd.
    Inventor: Uri Rapoport
  • Patent number: 7714580
    Abstract: An arrangement for producing an imaging region of increased maximum radial diameter in a magnetic resonance imaging (MRI) system, comprising a solenoidal magnet arrangement (30) comprising primary magnet coils (32) arranged symmetrically about an axis (A-A) and a shim coil set.
    Type: Grant
    Filed: March 6, 2008
    Date of Patent: May 11, 2010
    Assignee: Siemens Plc
    Inventor: Marcel Jan Marie Kruip
  • Publication number: 20100102819
    Abstract: The pursuit for ever higher field strengths and faster data acquisitions has led to the construction of coil arrays with high numbers of elements. With the SENSE technique it has been shown, how the sensitivity of those elements can be used for spatial image encoding. A method in accordance with the present invention, largely abstains from using encoding gradients. The resulting sensitivity encoded free induction decay (FID) data is then not used for imaging, but for determining field inhomogeneity distribution. The method has therefore been termed SSH for Sense SHimming.
    Type: Application
    Filed: October 27, 2008
    Publication date: April 29, 2010
    Inventors: Maxim ZAITSEV, Daniel N. SPLITTHOFF, Jurgen HENNIG
  • Patent number: 7706855
    Abstract: A system and method of MR imaging is disclosed that includes reconstruction of MR images with uniform or homogeneous fat suppression. An imaging process is performed using partial asymmetric acquisitions in conjunction with zero-filling of k-space for dynamic contrast-enhanced imaging. Data acquisition is carried out in a relatively short period of time which reduces scan time, reduces the likelihood of subject discomfort and motion-induced artifacts, and increases patient throughput.
    Type: Grant
    Filed: July 20, 2004
    Date of Patent: April 27, 2010
    Assignee: General Electric Company
    Inventors: Agus Priatna, Anthony T. Vu, Xiaoli Zhao
  • Patent number: 7701218
    Abstract: A magnet assembly for use in carrying out nuclear magnetic resonance experiments on a body or sample. The assembly comprises a set of superconducting coils within a cryostat, located about a bore, and arranged to generate a substantially uniform magnetic field in a primary working volume within the bore, and to generate a substantially uniform magnetic field in a secondary working volume within the coil structure and separate from the bore. At least part of a hyperpolarisation system intersects the at least one secondary working volume so as to hold a sample to be hyperpolarised in the secondary working volume.
    Type: Grant
    Filed: May 9, 2006
    Date of Patent: April 20, 2010
    Assignee: Oxford Instruments Molecular Biotools Limited
    Inventors: Paul Geoffrey Noonan, Robert Andrew Slade
  • Patent number: 7692426
    Abstract: In an arrangement with a basic field magnet and with a gradient coil of a magnetic resonance apparatus, the basic field magnet includes superconducting coils that are arranged in a reservoir with liquid helium for cooling. The helium reservoir is surrounded by a further reservoir, designated as an outer vacuum chamber. A vacuum exists between the outer vacuum chamber and the helium reservoir. A cryoshield is arranged between the outer vacuum chamber and the helium reservoir. The gradient coil is arranged in the inner chamber of the basic field magnet. The outer vacuum chamber has an additional coating with a high electrical conductivity.
    Type: Grant
    Filed: February 21, 2008
    Date of Patent: April 6, 2010
    Assignee: Siemens Aktiengesellschaft
    Inventors: Peter Dietz, Andreas Krug, Mark James Le Feuvre, Annette Lohfink, Thorsten Speckner
  • Patent number: 7683624
    Abstract: A magnetic field adjustment device for a superconducting magnet, wherein magnetic material shim mechanisms are arranged in an axial direction of an inside periphery of the cylindrical superconducting magnet, each of the magnetic material shim mechanisms including a combined shim tray (14 in FIG. 2) in which a plurality of divided shim trays (11 and 12) and shim tray spacers (13) inserted between the divided shim trays are rectilinearly coupled, and magnetic material shims (101) for magnetic field adjustments as are accommodated in the divided shim trays. The magnetic material shim mechanisms afford a high versatility of magnetic material shim arrangements, whereby a correctable range of a magnetic field uniformity can be widened.
    Type: Grant
    Filed: October 17, 2007
    Date of Patent: March 23, 2010
    Assignee: Mitsubishi Electric Corporation
    Inventor: Hajime Tamura
  • Patent number: 7667462
    Abstract: A nuclear magnetic resonance apparatus that may be used in connection with a variety of different tools, including a down-hole side-wall coring tool as well as with manufacturing process controllers. In one embodiment, the nuclear magnetic resonance apparatus may include a magnet assembly constructed around a sample chamber. The magnet assembly is constructed and arranged to provide a non-uniform magnetic field having a known magnetic field gradient inside the sample chamber. The use of gradient fields may allow for a more flexible and robust magnet assembly design that may be suitable for a variety of different applications.
    Type: Grant
    Filed: December 22, 2006
    Date of Patent: February 23, 2010
    Assignee: Schlumberger Technology Corporation
    Inventors: Yi-Qiao Song, Richard Gaylor
  • Patent number: 7646274
    Abstract: A comparatively light and compact permanent magnet arrangement for an MRI apparatus has a pair of opposed permanent magnet arrays with a shimming system to adjust the uniformity and strength of a magnetic field in a central chamber of the apparatus. The MRI apparatus is used to examine the extremities of a patient to determine cardiovascular characteristics from an analysis of the blood flow through selected arteries in the extremity. The information collected can be used to calculate such characteristics as total cardiac output, blood flow, arterial wall thickness and elasticity and the presence of plaque.
    Type: Grant
    Filed: April 30, 2004
    Date of Patent: January 12, 2010
    Inventor: Uri Rapoport
  • Patent number: 7639011
    Abstract: A field distribution correction element for positioning on an examination subject in a magnetic resonance system for local influencing of the radio-frequency field distribution during a magnetic resonance acquisition has a system of electrically conductive dipole strips essentially running in parallel, arranged on a carrier element. In a corresponding method for generation of magnetic resonance exposures of an examination subject in a magnetic resonance system, for local influencing of the radio-frequency field distribution, such a field distribution correction element is positioned on the patient.
    Type: Grant
    Filed: March 12, 2008
    Date of Patent: December 29, 2009
    Assignee: Siemens Aktiengesellschaft
    Inventors: Yvonne Candidus, Helmut Greim, Markus Vester, Steffen Wolf
  • Patent number: 7639013
    Abstract: With a view toward implementing a thermal controlling method for making reversible a temperature characteristic of a magnetic field generator using permanent magnets small in Hcj, a magnetic field generator whose temperature characteristic is reversible, using permanent magnets small in Hcj, and an MRI apparatus provided with such a magnetic field generator, there is provided a method for controlling the temperature of a magnetic field generator having a pair of disc-shaped permanent magnets whose magnetic poles opposite in polarity to each other are opposed to each other with spacing defined therebetween, and a yoke that forms return passes for magnetic fluxes of the permanent magnets, comprising the steps of raising the temperature from room temperature to a temperature higher than the room temperature, maintaining the temperature higher than the room temperature, and lowering the temperature from the temperature higher than the room temperature to the room temperature, whereby the temperature characteristi
    Type: Grant
    Filed: July 13, 2007
    Date of Patent: December 29, 2009
    Assignee: GE Medical Systems Global Technology Company, LLC
    Inventors: Fengshun Tan, Weijun Shen, Yihe Hua, Liang Liu
  • Patent number: 7635981
    Abstract: A magnetic resonance imaging apparatus is provided in which vibration of a gradient magnetic field coil is reduced, the vibration is not transmitted to a static magnetic field correcting unit, and space can be saved.
    Type: Grant
    Filed: May 13, 2008
    Date of Patent: December 22, 2009
    Assignee: Hitachi Medical Corporation
    Inventors: Akira Kurome, Yoshihide Wadayama
  • Publication number: 20090267607
    Abstract: An arrangement for the adjustment of the homogeneity of a basic magnetic field in a magnetic resonance apparatus includes gradient coil support fashioned to support a gradient coil system. The gradient coil support has at least one channel that is fashioned to accommodate an associated shim tray. The shim tray is designed to accommodate ferromagnetic shim elements at predetermined positions in order to adjust the homogeneity of the basic magnetic field of the magnetic resonance apparatus. The shim tray has a first locking element coupled with it. The channel has a second locking element, and the first and second locking element are shaped such that both are positively connected with one another by a force produced by the basic magnetic field of the magnetic resonance apparatus upon activation thereof.
    Type: Application
    Filed: April 23, 2009
    Publication date: October 29, 2009
    Inventors: Michael Eberler, Andreas Krug, Johann Schuster, Stefan Stocker
  • Patent number: 7606019
    Abstract: A magnet coil system (2) which is at least partially superconducting at a cryogenic temperature, comprising at least two partial coils (3, 4, 5) which are connected in series and are each bridged by a superconducting switch (6, 7, 8), such that the partial coils form independent electric loops (11, 12, 13) when the superconducting switches (6, 7, 8) are closed, is characterized in that two electric loops (11, 12) have a common section and a flux pump (10) is provided which is circuited in the common section (14) of the electric loops (11, 12) of two partial coils (3, 4), wherein the sum of the currents of the two partial coils (3, 4) flows through the flux pump (10) in the operating state. In this fashion, the drifts of two independent electric loops can be compensated for with a few devices.
    Type: Grant
    Filed: February 1, 2008
    Date of Patent: October 20, 2009
    Assignee: Bruker Biospin AG
    Inventors: Rolf Spreiter, Patrik Vonlanthen
  • Patent number: 7605589
    Abstract: A method for homogenizing a static magnetic field with a magnetic field distribution B0(r) for nuclear magnetic resonance spectroscopy by adjusting the currents Ci through the shim coils, thus creating spatial field distributions Ci·Si(r), where r stands for one, two, or three of the spatial dimensions x, y, and z, and said magnetic field distribution B0(r) has only a field component along z, in a working volume of a magnetic resonance apparatus with one or more radio frequency (=RF) coils (5) for inducing RF pulses and receiving RF signals within a working volume, said RF coils having a spatial sensitivity distribution of magnitudes B1k(r), and with shim coils (6) for homogenizing the magnetic field within the working volume, said shim coils (6) being characterized by their magnetic field distributions per unit current Si(r) and having components only along z, includes the following steps: (a) Mapping the magnetic field distribution B0(r) of the main magnetic field, (b) calculating a simulated spectrum IS
    Type: Grant
    Filed: October 18, 2007
    Date of Patent: October 20, 2009
    Assignee: Bruker BioSpin AG
    Inventors: Markus Weiger, Michael Fey, Thomas Speck
  • Patent number: 7592812
    Abstract: A magnetic resonance imaging apparatus includes: a static magnetic field generating unit which generates a static magnetic field, a measuring unit which measures the strength distribution characteristic of the static magnetic field, a determination unit which determines correction amounts for first- to nth-order (n is a natural number of more than one) components of the strength distribution characteristic of the static magnetic field by fixing the correction amount for at least one specific component which are part of the first- to nth-order components at a predetermined amount and determining the correction amounts for other components than the specific component on the basis of the strength distribution characteristic, and a correction magnetic field generating unit which generates correction magnetic fields to correct the static magnetic field on the basis of the correction amounts.
    Type: Grant
    Filed: March 30, 2007
    Date of Patent: September 22, 2009
    Assignees: Kabushiki Kaisha Toshiba, Toshiba Medical Systems Corporation
    Inventor: Masato Ikedo
  • Patent number: 7579837
    Abstract: The invention concerns an arrangement for magnetic field measurement of a measurement object (in particular a gradient coil in a magnetic resonance apparatus) with a magnetic field sensor that is designed to measure a magnetic field of the measurement object and with a measurement mechanism on which the magnetic field sensor is arranged at a first position. The measurement object has detectable reference points that can be used for calibration of a spatial position of a position sensor. The calibrated position sensor is arranged at a second position of the measurement mechanism, such that, with the first position and the second position, a spatial position relative to the measurement object can be associated with each magnetic field strength that is measured by the magnetic field sensor.
    Type: Grant
    Filed: May 29, 2008
    Date of Patent: August 25, 2009
    Assignee: Siemens Aktiengesellschaft
    Inventors: Sascha Fath, Alexander Granzer
  • Patent number: 7579838
    Abstract: Systems, methods and apparatus are provided through which a partially elongated field-of-view in a magnetic resonance imaging system is generated either by an asymmetric primary coil or a conventional symmetrical primary coil with a supplementary high odd-order shim that elongates the field-of-view towards one end of the bore. For significantly increased efficiency, the high odd-order shim can evoke specific parts of the primary coil by injecting additional current and/or subtracting current from specific turns, as required.
    Type: Grant
    Filed: November 18, 2005
    Date of Patent: August 25, 2009
    Assignee: General Electric Company
    Inventor: Timothy James Hollis
  • Publication number: 20090206839
    Abstract: A method for compensating for drift in a main magnetic field of a superconducting magnet in a magnetic resonance imaging (MRI) system includes measuring a pressure in a cryostat of the superconducting magnet. Based on the pressure, a parameter of an element of the MRI system is adjusted to correct or compensate for a change in the main magnetic field.
    Type: Application
    Filed: February 20, 2008
    Publication date: August 20, 2009
    Applicant: GENERAL ELECTRIC COMPANY
    Inventors: Derek A. Seeber, Anton M. Linz
  • Patent number: 7567158
    Abstract: A magnet arrangement (M, M?, M?, M??) for generating a magnetic field in the direction of a z-axis in a working volume (V) disposed on the z-axis about z=0, with a magnet coil system (A, A?, A?, A??) which comprises one or more superconducting magnet partial coil systems (A1, A1?, A1?, A1??, A2??, . . ., An??), each forming superconductingly short-circuited current paths in the operating state, and with a further coil system (C, C?, C?, C??) which can be charged or discharged independently of the magnet coil system (A, A?, A?, A??) and comprises a first and a second partial coil system (C1, C2, C1? C2?, C1?, C2?, C1??, C2??), wherein the first partial coil system (C1, C1?, C1?, C1??) and the second partial coil system (C2, C2?, C2?, C2??) each comprise at least one coil, wherein all coils of the further coil system (C, C?, C?, C??) are connected in series, wherein gCeff,diamag>0.1 mT/A, is characterized in that gC1eff,diamag>0.1 mT/A, gC2eff,diamag>0.
    Type: Grant
    Filed: May 6, 2008
    Date of Patent: July 28, 2009
    Assignee: Bruker Biospin AG
    Inventors: Francesca Venturini, Robert Schauwecker, Pierre-Alain Bovier
  • Patent number: 7554327
    Abstract: In a method for determination and evaluation of a shim parameter set for controlling a shim device in a magnetic resonance (MR) apparatus, the shim device is set using a first shim parameter set, a first field distribution is measured in a body region encompassing a target volume from which MR data are to be acquired, a second shim parameter set is determined using an algorithm for optimization of the field homogeneity in the target volume on the basis of the first shim parameter set and dependent on the first field distribution, a second field distribution is determined on the basis of the second shim parameter set, and the shim parameter sets are evaluated by indirect or direct comparison of the first field distribution and the second field distribution, in particular in the target volume.
    Type: Grant
    Filed: October 12, 2007
    Date of Patent: June 30, 2009
    Assignee: Siemens Aktiengesellschaft
    Inventors: Andrew Dewdney, Sabrina Harter
  • Patent number: 7543370
    Abstract: In a method for production of a superconducting magnetic coil, winding of superconducting wires of the superconducting magnetic coil is implemented with at least one UV-curable plastic, and the UV-curable plastic is at least partially cured with UV light during the winding. A magnetic resonance apparatus has a superconducting magnetic coil that is produced according to this method.
    Type: Grant
    Filed: March 30, 2007
    Date of Patent: June 9, 2009
    Assignee: Siemens Aktiengesellschaft
    Inventor: Gerhard Bittner