Magnetic resonance system

• US 4,875,485 A
• Filed: 04/19/1988
• Issued: 10/24/1989
• Est. Priority Date: 11/18/1985
• Status: Expired due to Fees

• Current Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: Matsutani, Kinya
• Primary Examiner(s): Smith, Ruth S.
• Application Number:
  US07/186,709
• Time in Patent Office: 553 Days
• Field of Search: 128/653, 324/307, 324/309, 324/318, 324/319, 324/322, 361/141, 335/216, 335/299, 378/198
• US Class Current: 600/415
• CPC Class Codes: G01R 33/28 Details of apparatus provided for in groups G01R33/44 - G01R33/64
• CPC Class Codes: G01R 33/3806 Open magnet assemblies for improved access to the sample, e.g. C-type or U-type magnets
• CPC Class Codes: G01R 33/381 using electromagnets

Abstract

A magnetic resonance system having a compact magnet configuration for generating a static magnetic field. The magnet and platform carrying the patient to be examined are so arranged as to be arbitrarily moved relative to one another. The resulting small size field-homogeneous space may be freely moved to various portions of the patient body to permit a wide range of whole body measurements.

Claims

1. A magnetic resonance system comprising:

a pair of magnets for generating a static field;

a plurality of gradient coils for generating plural gradient fields to be superimposed on said static field;

an RF coil for stimulating nuclei and for measuring field changes caused by said stimulation;

a platform for holding a body to be examined by placing said body thereon, within said static field;

driving means for automatically varying the position of each magnet independently and for varying a positional relationship between said magnets and said platform such that a field-homogeneous space can be established at an arbitrary position of said body to be examined; and

controlling means for automatically controlling said driving means, said gradient coils and said RF coil for measuring at least one of spin density distributions, relaxation time constant distributions and spectra, and for storing said measurements together with associated positional information corresponding to the respective portions within said body to be examined, and for providing cross-sectional images by synthesizing said stored data.

2. A magnetic resonance system as set forth in claim 1, wherein said pair of a magnets comprise a set of Helmholtz type air-core coils

3. A magnetic resonance system as set forth in claim 1, wherein said magnets comprise a single air-core coil and a field-concentrating magnetic material plate disposed opposite said air-core coil and perpendicular to a direction of the field generated by said air-core coil, said platform placed between said single air-core coil and said plate.

4. A magnetic resonance system as set forth in claim 1, wherein said magnets comprise a pair of Helmholtz-type air-core superconducting coils connected permanently to an excitation power source during operation of said magnets.

5. A magnetic resonance system as set forth in claim 4 further comprising a magnetic material member attached to each air-core coil for modifying the strength and homogeneity of said static field generated by said air-core coils.

6. A magnetic resonance system as set forth in claim 1, wherein said platform is oriented for holding said body to be examined such that the longitudinal axis of said body is perpendicular to the direction of said static field.

7. A magnetic resonance system as set forth in claim 6, wherein said driving means comprises three drive units for moving said magnets in three orthogonal directions and a fourth drive unit for moving said platform in an up/down direction.

8. A magnetic resonance system as set forth in claim 7, wherein each of said drive units are provided with position detectors respectively connected to said controlling means.

9. A magnetic resonance system as set forth in claim 6, wherein said driving means comprises three drive units for moving said platform in three orthogonal directions and a fourth drive unit that moves said magnets in an up/down direction, each of said drive units provided with position detectors respectively connected to said controlling means.

10. A magnetic resonance system comprising:

an upright support column;

a pair of support arms which are slidably attached to said support column;

magnet means consisting essentially of a pair of magnets for generating a static field which are attached on said support arms;

a plurality of gradient coils for generating plural gradient fields to be superimposed on said static field;

an RF coil for stimulating nuclei and for measuring field changes caused by said stimulation;

a platform for holding a body to be examined by placing said body thereon, within said static field;

driving means for automatically varying the position of each magnet independently and for varying a positional relationship between said magnets and said platform such that a field-homogeneous space can be established at an arbitrary position of said body to be examined; and

controlling means for automatically controlling said driving means, said gradient coils and said RF coil for measuring at least one of spin density distributions, relaxation time constant distributions and spectra, and for storing said measurements together with associated positional information corresponding to the respective portions within said body to be examined, and for providing cross-sectional images by synthesizing said stored data.