Magnetic resonance apparatus

• US 4,871,968 A
• Filed: 08/24/1988
• Issued: 10/03/1989
• Est. Priority Date: 08/25/1987
• Status: Expired due to Term

• Current Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: Kanayama, Shoichi
• Primary Examiner(s): NOT, DEFINED
• Assistant Examiner(s): NOT, DEFINED
• Application Number:
  US07/235,499
• Time in Patent Office: 405 Days
• Field of Search: 324/309, 324/318, 324/322
• US Class Current: 324/318
• CPC Class Codes: G01R 33/341 comprising surface coils
• CPC Class Codes: G01R 33/385 using gradient magnetic field coils

Abstract

A magnetic resonance apparatus comprises a main probe coil adapted for transmission and reception of a high frequency to and from a large region of an object under examination or for transmission of the high frequency to the object, a local probe coil formed of a surface coil adapted for transmission and reception of a high frequency to and from a local region corresponding to a local portion of the object or for reception of the high frequency, and a main gradient coil adapted for application of a gradient magnetic field to a large region of the object. The local probe coil is used for measurement of the local region. The magnetic resonance apparatus is further provided with a relatively small-sized local gradient coil for producing a local gradient magnetic field in the sensitive region of the local probe coil and its vicinities only.

Claims

1. A magnetic resonance apparatus comprising:

static magnetic field producing means for producing a homogeneous static magnetic field which is applied to an object under examination;

main gradient magnetic field producing means for producing a gradient magnetic field covering a relatively large region, which is superimposed upon the static magnetic field for application to the object;

local gradient magnetic field producing means for producing a local gradient magnetic field which is superimposed upon the static magnetic field for application to the object;

main probe means for applying a high frequency magnetic field to a relatively large region of the object and detecting a magnetic resonance signal produced within the region of the object;

local probe means magnetically coupled to only a local region of the object for performing at least one of first and second operations, the first operation applying a high frequency magnetic field to the local region of the object and the second operation detecting a magnetic resonance signal produced in the local region of the object;

system control means for controlling said static magnetic field producing means, said main gradient magnetic field producing means, said local gradient magnetic field producing means, said main probe means, and said local probe means in a predetermined pulse sequence; and

processing means for controlling said system control means and processing the magnetic resonance signal detected by one of said main probe means and said local probe means to obtain output information.

2. A magnetic resonance apparatus according to claim 1, wherein said local gradient magnetic field producing means and said local probe means are integrated into a unit.

3. A magnetic resonance apparatus according to claim 1, wherein said local probe means includes a surface coil.

4. A magnetic resonance apparatus according to claim 1, wherein said local gradient magnetic field producing means and said local probe means are integrated, and said local probe means includes a surface coil.

5. A magnetic resonance apparatus according to claim 4, wherein said local gradient magnetic field producing means produces a field gradient in a direction orthogonal to said surface coil.

6. A magnetic resonance apparatus according to claim 2, wherein there are provided a plurality of integrated units of said local gradient magnetic field producing means and said local probe means.

7. A magnetic resonance apparatus according to claim 1, wherein said main gradient magnetic field producing means includes coil means, and said local gradient magnetic field producing means includes coil means smaller than that of said main gradient magnetic field producing means.

8. A magnetic resonance apparatus comprising:

static magnetic field producing means for producing a homogeneous static magnetic field for application to an object under examination;

main gradient magnetic field producing means for producing a gradient magnetic field covering a relatively large region, which is superimposed upon the static magnetic field for application to the object;

local gradient magnetic field producing means for producing a local gradient magnetic field which is superimposed upon the static magnetic field for application to the object;

local probe means for applying a high frequency magnetic field to only a local region of the object and detecting a magnetic resonance signal produced in the local region of the object;

system control means for controlling said static magnetic field producing means, said main gradient magnetic field producing means, said local gradient magnetic field producing means, and said local probe means in a predetermined pulse sequence; and

processing means for controlling said system control means and processing the magnetic resonance signal detected by said local probe means to obtain output information.

9. A magnetic resonance apparatus according to claim 8, wherein said local gradient magnetic field producing means and said local probe means are integrated into a unit.

10. A magnetic resonance apparatus according to claim 8, wherein said local probe means includes a surface coil.

11. A magnetic resonance apparatus according to claim 8, wherein said local gradient magnetic field producing means and said local probe means are integrated, and said local probe means includes a surface coil.

12. A magnetic resonance apparatus according to claim 11, wherein said local gradient magnetic field producing means produces a field gradient in a direction orthogonal to said surface coil.

13. A magnetic resonance apparatus according to claim 9, wherein there are provided a plurality of integrated units of said local gradient magnetic field producing means and said local probe means.

14. A magnetic resonance apparatus according to claim 9, wherein said main gradient magnetic field producing means includes coil means, and said local gradient magnetic field producing means includes coil means smaller than that of said main gradient magnetic field producing means.