Magnetic resonance spectroscopy system

Claim 2

A magnetic resonance spectroscopy system comprising: static magnetic field applying means for applying a static magnetic field to an object under examination; gradient magnetic field applying means for applying gradient magnetic fields to the object; high frequency pulse applying means for applying a high frequency pulse including a 90° pulse to the object; detecting means for detecting a magnetic resonance signal from the object; control means for causing said static magnetic field applying means, said gradient magnetic field applying means, and said high frequency pulse applying means to operate in a predetermined sequence so as to induce magnetic resonance within the object; and data processing means for processing data based on the magnetic resonance signal detected by said detecting means to obtain magnetic resonance spectrum information; said control means including local excitation control means for repeatedly performing operations of: selectively exciting, using a first gradient magnetic field and a 90° pulse, first two regions which sandwich a desired local region therebetween in a first-axis direction for a predetermined slice portion; subsequently erasing transverse magnetization components in said first two regions; selectively exciting, using a second gradient magnetic field and a 90° pulse, second two regions which sandwich said desired local region therebetween in a second-axis direction normal to the first-axis direction for said slice portion; subsequently erasing transverse magnetization components in said second two regions; and sequentially exciting at least two regions having local regions aligned in a third-axis direction intersecting said slice to acquire magnetic resonance data therefor, repeatedly using a third gradient magnetic field and a high frequency pulse within a repetition time of the excitation of said desired local region; said data processing means obtaining a magnetic resonance spectrum of said local regions on the basis of magnetic resonance data acquired in the operations carried out by said local excitation control means.

Claim 3

A system according to claim 1, wherein said local excitation control means erases the transverse magnetization components in said first two regions by applying, immediately after the application of said 90° pulse, a spoiler pulse thereto.

Claim 4

A system according to claim 2, wherein the spoiler pulse is produced by abruptly raising the field strength in the vicinity of the trailing edge of a gradient magnetic field pulse simultaneously applied with the 90° pulse.

Claim 5

A system according to claim 1, wherein the 90° pulse is a selective excitation pulse.

Claim 6

A system according to claim 1, wherein said local excitation control means produces, as the 90° pulse for exciting said regions which sandwich said local region, a 90° pulse having frequency components corresponding to said regions.

Claim 7

A system according to claim 5, wherein the spoiler pulse is produced by abruptly raising the field strength in the vicinity of the trailing edge of a gradient magnetic field pulse simultaneously applied with the 90° pulse.

Claim 8

A system according to claim 5, wherein the 90° pulse s a selective excitation pulse.

Claim 9

A magnetic resonance spectroscopy system comprising: static magnetic field applying means for applying a static magnetic field to an object under examination; gradient magnetic field applying means for applying gradient magnetic fields to the object; high frequency pulse applying means for applying a high frequency pulse including a 90° pulse to the object; detecting means for detecting a magnetic resonance signal from the object; control means for causing said static magnetic field applying means, said gradient magnetic field applying means, and said high frequency pulse applying means to operate in a predetermined sequence so as to induce magnetic resonance within the object; and data processing means for processing data based on the magnetic resonance signal detected by said detecting means to obtain magnetic resonance spectrum information; said control means including local excitation control means for repeatedly performing operations of: selectively exciting, using a first gradient magnetic field and a 90° pulse, first two regions which sandwich a desired local region therebetween in a first-axis direction for a predetermined slice portion; subsequently erasing transverse magnetization components in said first two regions by applying, immediately after the application of said 90° pulse, a spoiler pulse thereto; selectively exciting, using a second gradient magnetic field and a 90° pulse, second two regions which sandwich said desired local region therebetween in a second-axis direction normal to the first-axis direction for said slice portion; subsequently erasing transverse magnetization components in said second two regions by applying, immediately after the application of said 90° pulse, the spoiler pulse thereto; exciting a region having one local region in a third-axis direction intersecting said slice to acquire magnetic resonance data therefor; and exciting a region having another local region in the third-axis direction to acquire magnetic resonance data therefor within a repetition time of the excitation of said desired local region, said spoiler pulse produced by abruptly raising the field strength in the vicinity of the trailing edge of a gradient magnetic field pulse simultaneously applied with the 90° pulse; said data processing means obtaining a magnetic resonance spectrum of said local regions on the basis of magnetic resonance data acquired in the operations carried out by said local excitation control means.

Claim 10

A magnetic resonance spectroscopy system comprising: static magnetic field applying means for applying a static magnetic field to an object under examination; gradient magnetic field applying means for applying gradient magnetic fields to the object; high frequency pulse applying means for applying a high frequency pulse including a 90° pulse to the object; detecting means for detecting a magnetic resonance signal from the object; control means for causing said static magnetic field applying means, said gradient magnetic field applying means, and said high frequency pulse applying means to operate in a predetermined sequence so as to induce magnetic resonance within the object; and data processing means for processing data based on the magnetic resonance signal detected by said detecting means to obtain magnetic resonance spectrum information; said control means including local excitation control means for repeatedly performing operations of: selectively exciting, using a first gradient magnetic field and a 90° pulse, first two regions which sandwich a desired local region therebetween in a first-axis direction for a predetermined slice portion; subsequently erasing transverse magnetization components in said first two regions by applying, immediately after the application of said 90° pulse, a spoiler pulse thereto; selectively exciting, using a second gradient magnetic field and a 90° pulse, second two regions which sandwich said desired local region therebetween in a second-axis direction normal to the first-axis direction for said slice portion; subsequently erasing transverse magnetization components in said second two regions by applying, immediately after the application of said 90° pulse, the spoiler pulse thereto; exciting a region having one local region in a third-axis direction intersecting said slice to acquire magnetic resonance data therefor; and exciting a region having another local region in the third-axis direction to acquire magnetic resonance data therefor within a repetition time of the excitation of said desired local region, said spoiler pulse produced by abruptly raising the field strength in the vicinity of the trailing edge of a gradient magnetic field pulse simultaneously applied with the 90° pulse; said data processing means obtaining a magnetic resonance spectrum of said local regions on the basis of magnetic resonance data acquired in the operations carried out by said local excitation control means.

Claim 11

A magnetic resonance spectroscopy system comprising: static magnetic field applying means for applying a static magnetic field to an object under examination; gradient magnetic field applying means for applying gradient magnetic fields to the object; high frequency pulse applying means for applying a high frequency pulse including a 90° pulse to the object; detecting means for detecting a magnetic resonance signal from the object; control means for causing said static magnetic field applying means, said gradient magnetic field applying means, and said high frequency pulse applying means to operate in a predetermined sequence so as to induce magnetic resonance within the object; and data processing means for processing data based on the magnetic resonance signal detected by said detecting means to obtain magnetic resonance spectrum information; said control means including local excitation control means for repeatedly performing operations of: selectively exciting first two regions which sandwich a desired local region therebetween in a first-axis direction for a predetermined slice portion, using a first gradient magnetic field and a 90° pulse having frequency components corresponding to said first two regions; subsequently erasing transverse magnetization components in said first two regions; selectively exciting second two regions which sandwich said desired local region therebetween in a second-axis direction normal to the first-axis direction for said slice portion, using a second gradient magnetic field and a 90° pulse having frequency components corresponding to said second two regions; subsequently erasing transverse magnetization components in said second two regions; exciting a region having one local region in a third-axis direction intersecting said slice to acquire magnetic resonance data therefor; and exciting a region having another local region in the third-axis direction to acquire magnetic resonance data therefor within a repetition time of the excitation of said desired local region, said spoiler pulse is produced by abruptly raising the field strength in the vicinity of the trailing edge of a gradient magnetic field pulse simultaneously applied with the 90° pulse; said data processing means obtaining a magnetic resonance spectrum of said local regions on the basis of magnetic resonance data acquired in the operations carried out by said local excitation control means.

Claim 12

A magnetic resonance spectroscopy system comprising: static magnetic field applying means for applying a static magnetic field to an object under examination; gradient magnetic field applying means for applying gradient magnetic fields to the object; high frequency pulse applying means for applying a high frequency pulse including a 90° pulse to the object; detecting means for detecting a magnetic resonance signal from the object; control means for causing said static magnetic field applying means, said gradient magnetic field applying means, and said high frequency pulse applying means to operate in a predetermined sequence so as to induce magnetic resonance within the object; and data processing means for processing data based on the magnetic resonance signal detected by said detecting means to obtain magnetic resonance spectrum information; said control means including local excitation control means for repeatedly performing operations of: selectively exciting first two regions which sandwich a desired local region therebetween in a first-axis direction for a predetermined slice portion, using a first gradient magnetic field and a 90° pulse having frequency components corresponding to said first two regions; subsequently erasing transverse magnetization components in said first two regions; selectively exciting second two regions which sandwich said desired local region therebetween in a second-axis direction normal to the first-axis direction for said slice portion, using a second gradient magnetic field and a 90° pulse having frequency components corresponding to said second two regions; subsequently erasing transverse magnetization components in said second two regions; exciting a region having one local region in a third-axis direction intersecting said slice to acquire magnetic resonance data therefor; and exciting a region having another local region in the third-axis direction to acquire magnetic resonance data therefor within a repetition time of the excitation of said desired local region, said spoiler pulse is produced by abruptly raising the field strength in the vicinity of the trailing edge of a gradient magnetic field pulse simultaneously applied with the 90° pulse; said data processing means obtaining a magnetic resonance spectrum of said local regions on the basis of magnetic resonance data acquired in the operations carried out by said local excitation control means.