JPH09262221A - Magnetic resonance diagnostic apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To aim at three axis localization by utilizing slice selecting pulse of HMQC method. SOLUTION: The magnetic resonance diagnostic apparatus comprises a IH transmitting unit 7 for exposing the first exciting pulse, the second reimaging pulse and the third reimaging pulse to 1H in the order, a 13C transmitting unit 8 for exposing the fourth exciting pulse to 13C after the lapse of the time of 1/(2.J) hour from the echo time corresponding to the first exciting pulse and the second reimaging pulse, and for exposing the fifth exciting pulse after exposing the fourth exciting pulse and the third reimaging pulse. And also the apparatus comprises a gradient coil electric source 5 for generating a gradient magnetic field pulse for slice selection together with the first exciting pulse, the second reimaging pulse and the third reimaging pulse respectively regarding different axis and 1H receiver 9 for observing signals from 1H and a calculating system 12 for reconstructing diagnostic information based on the signals.

Description

Detailed Description of the Invention

[0001]

The present invention relates to the which is one HMQC of the ¹ H observation method (Heteronuclear Multiple-Quantum-Cohe
The present invention relates to a magnetic resonance diagnostic apparatus capable of performing rence).

[0002]

2. Description of the Related Art The mainstream of magnetic resonance diagnostic imaging is to non-invasively image the distribution of water in a living body by detecting ¹ H of water molecules, and is widely used clinically. However, with the current water distribution image, only morphological information can be obtained.

On the other hand, metabolite information in the living body can be obtained by detecting, for example, ¹ H, ¹³ C or ³¹ P of a metabolite, so that multinuclear NMR (Nuclear Magnification) can be obtained.
eticResonance) has been the subject of much research. Of these, ¹³ C-NMR has been drawing attention in recent years.
¹³ C in order natural abundance of 1.1% of low, can track the state of metabolism after ¹³ C-labeled substance administration, ¹ H Ya
Metabolic information different from ³¹ P can be obtained.

However, this ¹³ C-NMR has a problem of low detection sensitivity, and methods such as decoupling and polarization transfer have been developed to alleviate this problem.
Of these methods, the method that has received the most attention in recent years is to improve S / N by observing ¹ H bound to ¹³ C ¹
H observation method.

^{One of the 1} H observation methods is a method called HMQC method developed by LJMuller using multiple quantum transitions and improved by A. Bax (LJ Muller, J. Am. Chem. So
c.101,4481, (1979), A, Bax et al., J.Am.Chem.Soc.105,7
188 (1983)). The pulse sequence of the HMQC method is shown in FIGS.

In this pulse sequence, ¹ H is first excited by a high-frequency magnetic field pulse having a flip angle of 90 ° (hereinafter abbreviated as an excitation pulse). From this high-frequency magnetic field pulse,
After 1 / (2 · J) time, an excitation pulse is applied to ¹³ C. This excitation pulse ¹³ multiple-quantum transitions (0 quantum transitions, 2 quantum transition) to the second excitation pulse for C in the period t _1, the information of ¹³ C chemical shifts are added to the signal. Returning to second time ¹ H-side magnetized by the excitation pulses for the ¹³ C, the magnetic resonance signals by the ¹ H in a state ^{of 13} C of the information are bound is added is observed in data acquisition period t _2.

[0007] Such a series of pulse sequences is repeated while changing the length of the multiquantum transition period t ₁ , and a two-dimensional data sequence S (t ₁ , t ₂ ) is obtained. A two-dimensional Fourier transform is performed on the t ₁ axis and the t ₂ axis for the acquired two-dimensional data string S (t ₁ , t ₂ ).
Thus, the chemical shift of ¹³ C as shown in FIG. 11 ¹
Let H be the chemical shift of 2 orthogonal axes (ω ¹ H, ω ¹³ C)
A dimensional spectrum can be obtained. ^Since the chemical shift range of ¹³ C is wider than that of ¹ H, 2
It has the advantage that separation of metabolites is facilitated by dimensioning.

[0008] Since the HMQC method is a ¹ H observation method, mixing of a water signal becomes a problem. To remove the water signal, a pre-pulse for removing a water signal such as a CHESS pulse (chemical shift selection pulse) is used. Phase cycling and difference processing were needed to add and remove residual water signals.

On the other hand, REHurd et al. Proposed a method of performing coherence selection using a gradient magnetic field (RE
Hurd et al., J. Magn. Reson, 20191, 648, 1991). FIG.
Shows the HMQC pulse sequence improved for coherence selection. In this pulse sequence,
0,2 to select only quantum transitions, the multiple quantum transition period t _1, applying a gradient magnetic field Gselection. Thereby, the water signal which is one quantum transition can be removed. As a result, it became possible to detect only ¹ H bound to ¹³ C in one measurement, and it was possible to reduce the influence of motion, which was a problem in phase cycling and difference processing. In fact, PCM van Zijl and others
In Medicine, vol.30 P544 to P551 (1993), in vivo two-dimensional N using the pulse sequence of FIG.
The MR spectrum is reported.

Further, PCM van Zijl et al., As shown in FIG. 13, have made an improvement so that an initial excitation pulse for ¹ H is applied as a slice selection pulse together with a gradient selection magnetic field Gslice. However, in order to obtain useful information in actual diagnosis, it is essential to spatially limit the localization, that is, localize three axes.

[0011]

SUMMARY OF THE INVENTION An object of the present invention is to provide an HM
It is an object of the present invention to provide a magnetic resonance diagnostic apparatus capable of observing a signal sufficiently spatially localized in the QC method.

[0012]

According to the magnetic resonance diagnostic apparatus of the present invention, a first radio-frequency magnetic field pulse for excitation, a second radio-frequency magnetic field pulse for re-imaging, is applied to a first nuclide. A multi-quantum transition is generated with respect to a first radio frequency magnetic field applying means for sequentially applying a third radio frequency magnetic field pulse for re-imaging and a second nuclide spin-spin coupled with the first nuclide. To this end, a fourth high-frequency magnetic field pulse for excitation is applied between the second high-frequency magnetic field pulse and the third high-frequency magnetic field pulse, and the multi-quantum transition after the fourth high-frequency magnetic field pulse is applied. A second radio frequency magnetic field pulse for excitation is applied after the third radio frequency magnetic field pulse to generate one quantum transition of the first nuclide and collect the signal of the first nuclide. High-frequency magnetic field applying means of
Generating a first gradient magnetic field pulse for slice selection about the first axis together with the first high frequency magnetic field pulse for using the first high frequency magnetic field pulse as a slice selection pulse about the first axis; Second high-frequency magnetic field pulse is used together with the second high-frequency magnetic field pulse to generate the second slice-selecting gradient magnetic-field pulse for the second axis, and the third high-frequency magnetic field pulse is generated. Gradient magnetic field generating means for generating a third slice selection gradient magnetic field pulse relating to the third axis together with the third radio frequency magnetic field pulse for using the pulse as a slice selection pulse relating to the third axis;
It comprises means for observing a magnetic resonance signal from the first nuclide and means for generating diagnostic information based on the magnetic resonance signal.

Further, the gradient magnetic field generating means generates only the first slice selection gradient magnetic field pulse and the slice refocusing gradient magnetic field pulse with respect to the first axis, and the second magnetic field with respect to the second axis. Only a slice selection gradient magnetic field pulse and a dephase gradient magnetic field pulse are generated, and only the third slice selection gradient magnetic field pulse and a dephase gradient magnetic field pulse are generated with respect to the third axis.

Further, the second high-frequency magnetic field applying means includes a spin-spin coupling constant between the first nuclide and the second nuclide, where n is a positive number, and the first high-frequency magnetic field pulse and the second (2n + 1) / (4 · J) before the echo time of the echo generated by the first high-frequency magnetic field pulse, or (2n + 1) / (4) before the first high-frequency magnetic field pulse.
J) A seventh high-frequency magnetic field pulse for reversal is applied to the second nuclide later.

Further, the first high-frequency magnetic field applying means may include a sixth high-frequency magnetic field applying means for exciting after the second high-frequency magnetic field pulse.
Wherein said high frequency magnetic field pulse is applied to said first nuclide.

Further, the second high-frequency magnetic field applying means includes a spin-spin coupling constant between the first nuclide and the second nuclide, where n is a positive number, and the first high-frequency magnetic field pulse and the second The second high frequency magnetic field is applied to the second nuclide after (2n + 1) / (2 · J) from the echo time of the echo generated by the high frequency magnetic field pulse.

Further, the second high-frequency magnetic field applying means alternately inverts the phase of the fourth high-frequency magnetic field pulse or the fifth high-frequency magnetic field pulse every time the first high-frequency magnetic field pulse is repeated. It is characterized by.

According to the present invention, the following effects can be obtained. After the multi-quantum transition is generated by the fourth high-frequency magnetic field pulse, a multi-quantum transition is generated between the fourth high-frequency magnetic field pulse and the fifth high-frequency magnetic field pulse, and the first nuclide is generated by the fifth high-frequency magnetic field pulse. , A magnetic resonance signal is observed. HMQ, one of the so-called ¹ H observation methods
C can be realized.

In the HMQC, ^{first and} third high-frequency magnetic field pulses are indispensably applied to ¹ H. These first,
By using three high frequency magnetic field pulses as slice selection pulses, localization of two axes can be achieved. In the present invention, for localization of the third axis, a second high-frequency magnetic field pulse as a re-imaging pulse for ¹ H is added between the first and third high-frequency magnetic field pulses. From the echo time corresponding to the second high-frequency magnetic field pulse, for example, (2n + 1)
A multi-quantum transition is generated by applying a fourth high-frequency magnetic field pulse to the second nuclide after / (2 · J).
By applying the first to third high-frequency magnetic field pulses for ¹ H as slice selection pulses for different axes, signal observation from a spatially sufficiently localized region is realized, which is useful in actual diagnosis. Information can be obtained. In many cases, the first nuclide has a narrower chemical shift range than the second nuclide. By realizing all three-axis localization with the high-frequency magnetic field pulse for the first nuclide, the high-frequency magnetic field pulse for the second nuclide is obtained. Can be kept small as compared with the case where is localized as a slice selection pulse.

[0020]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings. Here, a combination of ¹ H (first nuclide) and ¹³ C (second nuclide) will be described as an example of a combination of a concentrated spin and a diluted spin that are spin-spin coupled. However, the combination is not limited to ¹ H and ¹³ C, but may be ¹ H and ¹⁵ N, for example. FIG. 1 is a block diagram showing the configuration of the magnetic resonance diagnostic apparatus according to the present embodiment, in which the spin-spin coupling constant between ¹ H and ¹³ C is represented by “J”. In the figure, the static magnetic field magnet 1 applies a uniform static magnetic field to a subject (not shown). Here, the direction of the static magnetic field is defined as the z direction. The gradient coil 2 provided inside the static magnetic field magnet 1 receives a drive current from the gradient coil power supply 5 and generates a gradient magnetic field in three mutually orthogonal x, y, and z directions. The shim coil 3 is driven by a shim coil power supply 6 and generates a magnetic field for correcting an inhomogeneous component of a static magnetic field.

The probe 4 provided inside the gradient coil 2 receives a supply of a high-frequency current having a resonance frequency specific to ¹ H from the ¹ H transmission section 7 and applies a high-frequency magnetic field pulse to the subject. Thereby, the magnetization of ¹ H is selectively affected.

A high-frequency magnetic field pulse having a flip angle of 90 ° for exciting the magnetization is called an excitation pulse.
180 ° flip angle for re-imaging (reversing) magnetization
The high frequency magnetic field pulse is referred to as a re-imaging pulse and will be used as appropriate hereinafter.

The probe 4 receives a signal from the ¹³ C transmitter 8
^With the supply of a high-frequency signal having a resonance frequency specific to ¹³ C,
A high frequency magnetic field pulse is applied to the subject. This makes ¹³ C
Is selectively affected.

[0024: ¹ H receiver 9, ¹ H through the probe 4
Selectively receive magnetic resonance signals from the. The data collecting unit 11 detects the received signal output from the ¹ H receiving unit 9, converts the signal into a digital signal, and
Feed to 2. The probe 3 may be provided for both transmission and reception, or separately provided for transmission only and reception only. Based on the output of the data collection unit 11, the computer system 12 sets a chemical shift of ¹³ C and a chemical shift of ¹ H as shown in FIG. 11, for example, as two orthogonal axes (ω ¹ H, ω ¹³ C). Reconstruct diagnostic information such as spectra. This diagnostic information is sent to the image display 14 and displayed. The console 13 is connected to the computer system 12 for an operator to input necessary commands and information.

The sequence control unit 10 controls operations of the gradient coil power supply 5, the shim coil power supply 6, the reception unit 8, and the data collection unit 9 to execute a pulse sequence described later.

FIG. 2 shows the pulse sequence of the improved HMQC. This pulse sequence should be referred to in comparison with the conventional pulse sequence shown in FIG. FIG.
The improved HMQC pulse sequence of FIG.
Conventional as understood in comparison with the pulse sequence shown in the second to be described later as a re-imaging pulse for ¹ H
A high frequency magnetic field pulse has been added.

An excitation pulse (first high-frequency magnetic field pulse), a re-imaging pulse (second high-frequency magnetic field pulse), and a re-imaging pulse (third high-frequency magnetic field pulse) are sequentially applied to ¹ H. You.

On the other hand, an excitation pulse (fourth high-frequency magnetic field pulse) and an excitation pulse (fifth high-frequency magnetic field pulse) are sequentially applied to ¹³ C. The fourth high-frequency magnetic field pulse is
^In order to realize the polarization transfer from ¹ H to ¹³ C, between the second high frequency magnetic field pulse and the third high frequency magnetic field pulse, the first high frequency magnetic field pulse and the second high frequency magnetic field pulse are used. From the corresponding echo time, (2 · n + 1) / (2 ·
J) Applied after time. Note that n is a positive number. In this pulse sequence, since the chemical shift of ¹ H is re-imaged at the echo time, the same effect as in the pulse sequence of FIG. 10 can be obtained, and ¹ H observation using multiple quantum transitions can be made possible.

The fifth high frequency magnetic field pulse for ¹³ C is generated after the third high frequency magnetic field pulse for ¹ H. A multi-quantum transition occurs in a period t ₁ from the fourth high-frequency magnetic field pulse to the fifth high-frequency magnetic field pulse. Polarization transfer is caused from ¹³ C to ¹ H by the fifth high-frequency magnetic field pulse, and a magnetic resonance signal can be observed from ¹ H in a period t ₂ after the fifth high-frequency magnetic field pulse.

FIG. 3 shows an HMQC pulse sequence for three-axis localization. It is the same as FIG. 2 except for the gradient magnetic fields Gx, Gy and Gz. The first, second, and third high-frequency magnetic field pulses, including the added second high-frequency magnetic field pulse, are applied together with the gradient magnetic field pulse as slice selection pulses for different axes. That is, in order to use the first high-frequency magnetic field pulse as a slice selection pulse on the first axis (x-axis), the first slice selection gradient magnetic field pulse Gx on the first axis together with the first high-frequency magnetic field pulse is used. Generated. Further, since the second high-frequency magnetic field pulse is used as the slice selection pulse for the second axis (y-axis), the second high-frequency magnetic field pulse and the second slice-selection gradient magnetic field pulse Gy for the second axis are generated. Is generated. Further, in order to use the third high-frequency magnetic field pulse as a slice selection pulse on the third axis (z-axis), together with the third high-frequency magnetic field pulse, the third slice selection gradient magnetic field pulse Gz on the third axis is used. Generated.

As described above, by using the high-frequency magnetic field pulse for ¹ H as a slice selection pulse, localization of three axes can be realized. The chemical shift range of ¹ H is narrower than that of ¹³ C. Therefore, 3
By applying the high frequency magnetic field pulse on the ¹ H side to the slice selection pulse on the axis, it is possible to reduce the deviation of the region selection position for each metabolite compared to using the high frequency magnetic field pulse for ¹³ C as the slice selection pulse. Can be possible.

The pulse sequence has the following features. With respect to the same first axis (x-axis) as the first slice selection gradient magnetic field pulse Gx generated together with the first high frequency magnetic field pulse for the excitation of ¹ H, this first slice selection gradient magnetic field pulse is used. Only Gx and a slice refocusing gradient magnetic field pulse (oblique line) are generated. ^A second slice-selecting gradient magnetic field pulse Gy generated together with a second high-frequency magnetic field pulse for reimaging ¹ H
With respect to the same second axis (y-axis) as above, only the second slice selection gradient magnetic field pulse Gy and the dephase gradient magnetic field pulse (oblique lines) are generated. Similarly, the third slice selection gradient magnetic field pulse Gz, which is the same as the third slice selection gradient magnetic field pulse Gz generated together with the third high-frequency magnetic field pulse for ¹ H reimaging, is also used.
, The third slice selection gradient magnetic field pulse Gz and the dephase gradient magnetic field pulse (shaded line) are generated. This can make it possible to reduce the mixing of signals from magnetization outside the desired local region.

Next, another method of localizing a pulse sequence will be described. This is an improvement of the conventional HMQC pulse sequence shown in FIG. Conventional HMQC of FIG.
As can be understood with reference to the pulse sequence of ¹ H, at least three RF magnetic field pulses are applied to ¹ H, but the second and third RF magnetic field pulses to ¹ H are ¹³ C. Since it was applied at the same time as the high frequency magnetic field pulse with respect to, it could not be used as a slice selection pulse. In the present invention, this problem is solved as follows, and the localization of all three axes is realized by using a high-frequency magnetic field pulse for ¹ H as a slice selection pulse.

FIG. 4 shows a pulse sequence in which localization of three axes is realized by a slice selection pulse for ¹ H.
^{For 1} H, an excitation pulse (first high-frequency magnetic field pulse), a re-imaging pulse (second high-frequency magnetic field pulse), an excitation pulse (sixth high-frequency magnetic field pulse), and a re-imaging pulse (third high-frequency magnetic field pulse) Magnetic field pulses) are applied in sequence. The sixth high frequency magnetic field pulse is generated at an echo time corresponding to the first high frequency magnetic field pulse and the second high frequency magnetic field pulse.
The sixth high-frequency magnetic field pulse is an excitation pulse for reducing the magnetization of ¹ H such as water other than ¹ H coupled to ¹³ C into longitudinal magnetization to reduce the water signal, as shown in FIG. May be omitted.

On the other hand, an inversion pulse (seventh high-frequency magnetic field pulse), an excitation pulse (fourth high-frequency magnetic field pulse), and an excitation pulse (fifth high-frequency magnetic field pulse) are sequentially applied to ¹³ C. The inversion pulse is a high-frequency magnetic field pulse having a flip angle of 180 ° like the re-imaging pulse.

The seventh high-frequency magnetic field pulse is between the second high-frequency magnetic field pulse and the sixth high-frequency magnetic field pulse,
(2 · n + 1) / (4 · J) hours before the echo time, or (2 · n + 1) / (4 · J) from the first high-frequency magnetic field pulse.
It is applied after (n + 1) / (4 · J) hours. As a result, the polarization transfer from ¹ H to ¹³ C is realized, and the period t from the fourth high-frequency magnetic field pulse to the fifth high-frequency magnetic field pulse is t.
_A zero quantum transition or a two quantum transition can be generated in one. That is, the first and second high frequency magnetic field pulses for ¹ H
^{1 1} H chemical shift is re-imaged, were bound to ¹³ C by inversion pulse for ¹³ C (seventh RF magnetic field pulse)
Since the movement of H is reversed, 2IySz
(Transition path) occurs. In this state, if an excitation pulse (fourth high-frequency magnetic field pulse) is applied to ¹³ C, a 0 quantum transition or a 2 quantum transition can be generated.

The time interval from the first high-frequency magnetic field pulse to ¹ H to the second high-frequency magnetic field pulse and the time interval from the second high-frequency magnetic field pulse to ¹ H to the echo time are (2 · n + 1) / ( 4 · J) The time is set longer than the time.

With such a time setting, the second high-frequency magnetic field pulse for ¹ H can be generated at a different time from the seventh high-frequency magnetic field pulse for ¹³ C. Therefore, the second high-frequency magnetic field pulse can be used as a slice selection pulse.

That is, as shown in FIGS. 6 and 7, the first, second and third high-frequency magnetic field pulses including the second high-frequency magnetic field pulse shifted from the seventh high-frequency magnetic field pulse This is applied together with the gradient magnetic field pulse as a slice selection pulse for each different axis. That is, in order to use the first high-frequency magnetic field pulse as a slice selection pulse on the first axis (x-axis), the first slice selection gradient magnetic field pulse Gx on the first axis together with the first high-frequency magnetic field pulse is used. Generated. In order to use the second high-frequency magnetic field pulse as a slice selection pulse about the second axis (y-axis), together with the second high-frequency magnetic field pulse,
A second slice selection gradient magnetic field pulse Gy for the second axis is generated. Further, in order to use the third high-frequency magnetic field pulse as a slice selection pulse on the third axis (z-axis), together with the third high-frequency magnetic field pulse, the third slice selection gradient magnetic field pulse Gz on the third axis is used. Generated.

As described above, by using the high-frequency magnetic field pulse for ¹ H as the slice selection pulse, localization of three axes can be realized. As in the previous pulse sequence, the chemical shift range of ¹ H is relatively narrow, while ¹³
The chemical shift range of C is relatively wide. Therefore, by applying a high-frequency magnetic field pulse on the ¹ H side to all three slice selection pulses, the deviation of the region selection position for each metabolite is smaller than using a high-frequency magnetic field pulse for ¹³ C as a slice selection pulse. It may be possible to

Also, this pulse sequence has the following features as in the previous pulse sequence. ^A second slice-selecting gradient magnetic field pulse Gy generated together with a second high-frequency magnetic field pulse for reimaging ¹ H
With respect to the same second axis (y-axis) as above, only the second slice selection gradient magnetic field pulse Gy and the dephase gradient magnetic field pulse (oblique lines) are generated. Similarly, the third slice selection gradient magnetic field pulse Gz, which is the same as the third slice selection gradient magnetic field pulse Gz generated together with the third high-frequency magnetic field pulse for ¹ H reimaging, is also used.
, The third slice selection gradient magnetic field pulse Gz and the dephase gradient magnetic field pulse (shaded line) are generated. This can make it possible to reduce the mixing of signals from magnetization outside the desired local region.

HMQC that enables localization of three axes
The pulse sequence has been described. In these pulse sequences, a water signal suppression pulse set such as a CHESS pulse (chemical shift selection pulse) may be used as a pre-pulse, as shown in FIG.

In the above pulse sequence,
^The phase cycle method may be applied to the fourth high-frequency magnetic field pulse or the fifth high-frequency magnetic field pulse for ¹³ C. The phase cycle is a method of alternately inverting the phase of the fourth high-frequency magnetic field pulse or the fifth high-frequency magnetic field pulse every time the first high-frequency magnetic field pulse (pulse sequence) is repeated. The residual water signal component can be removed by subtracting the signals subjected to the seed frequency. In addition, the present invention is not limited to the above-described embodiment, and can be implemented with various modifications.

[0044]

According to the present invention, the following effects can be realized. In HMQC, first against ¹ H 1, 3
Are applied as essential. By using these first and third high frequency magnetic field pulses as slice selection pulses, localization of two axes can be achieved. According to the present invention, the second high-frequency magnetic field pulse as the re-imaging pulse for ¹ H
Is added between high frequency magnetic field pulses. From the echo time of the echo generated by the first high-frequency magnetic field pulse and the second high-frequency magnetic field pulse, for example, (2n + 1) / (2
J) A multi-quantum transition is subsequently generated by applying a fourth radio-frequency magnetic field pulse to the second nuclide.

By applying the first to third high-frequency magnetic field pulses for ¹ H as slice selection pulses for different axes, signal observation from a spatially sufficiently localized local area is realized. And useful information can be obtained.

In many cases, the first nuclide has a narrower chemical shift range than the second nuclide, and the localization of all three axes is realized by a high-frequency magnetic field pulse for the first nuclide. Spatial deviation can be suppressed as compared with the case where the high-frequency magnetic field pulse is localized as the slice selection pulse.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a magnetic resonance diagnostic apparatus according to an embodiment of the present invention.

FIG. 2 is a diagram showing a pulse sequence for explaining the principle of realizing three-axis localization.

FIG. 3 is a view showing a pulse sequence for realizing three-axis localization corresponding to FIG. 2;

FIG. 4 is a diagram showing another pulse sequence for explaining the principle of realizing three-axis localization.

FIG. 5 is a diagram showing a modification of FIG. 4;

FIG. 6 is a view showing a pulse sequence for realizing three-axis localization corresponding to FIG. 4;

FIG. 7 is a view showing a pulse sequence for realizing three-axis localization corresponding to FIG. 5;

FIG. 8 is a view showing a modification of FIG.

FIG. 9 is a diagram showing a pulse sequence of a conventional HMQC.

FIG. 10 is a diagram showing another pulse sequence of the conventional HMQC.

FIG. 11 is a diagram showing an example of a two-dimensional correlation spectrum of ¹ H and ¹³ C.

FIG. 12 is a diagram showing a conventional HMQC pulse sequence for multi-quantum transition selection.

FIG. 13 is a diagram showing a conventional HMQC pulse sequence for realizing one-axis localization.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Static magnetic field magnet, 2 ... Gradient coil, 3 ... Shim coil, 4 ... Probe, 5 ... Gradient coil power supply, 6 ... Shim coil power supply, 7 ... ¹ H transmission part, 8 ... ¹³ C transmission part, 9 ... ¹ H reception part Reference numeral 10: Sequence control unit, 11: Data collection unit, 12: Computer system, 13: Console, 14: Image display.

Claims (6)

[Claims] 1. A first nuclide, a first nuclide
First high-frequency magnetic field applying means for sequentially applying the high-frequency magnetic field pulse of, the second high-frequency magnetic field pulse for re-imaging, and the third high-frequency magnetic field pulse for re-imaging, and the first nuclide and spin. For the spin-coupled second nuclide, a fourth high-frequency magnetic field pulse for excitation for causing a multiquantum transition is generated by combining the second high-frequency magnetic field pulse and the third high-frequency magnetic field pulse. Applied between the first high frequency magnetic field pulse and the multiquantum transition after the fourth high frequency magnetic field pulse.
Second high frequency magnetic field application for applying a fifth high frequency magnetic field pulse for excitation after the third high frequency magnetic field pulse in order to generate one quantum transition of the nuclide and collect the signal of the first nuclide. Generating a first slice selection gradient magnetic field pulse with respect to the first axis together with the first high frequency magnetic field pulse for using the first high frequency magnetic field pulse as a slice selection pulse with respect to a first axis; Generating a second gradient magnetic field pulse for slice selection about the second axis together with the second high frequency magnetic field pulse for using the second high frequency magnetic field pulse as a slice selection pulse about the second axis; Third radio frequency magnetic field pulse for use as a slice selection pulse for the third axis together with the third radio frequency magnetic field pulse for the third axis A gradient magnetic field generating means for generating a gradient magnetic field pulse for selection; a means for observing a magnetic resonance signal from the first nuclide; and a means for generating diagnostic information based on the magnetic resonance signal. Magnetic resonance diagnostic device. 2. The gradient magnetic field generation means generates only the first slice selection gradient magnetic field pulse and the slice refocusing gradient magnetic field pulse with respect to the first axis, and generates the second magnetic field with respect to the second axis. 2. The apparatus according to claim 1, wherein only a slice selection gradient magnetic field pulse and a dephase gradient magnetic field pulse are generated, and only the third slice selection gradient magnetic field pulse and a dephase gradient magnetic field pulse are generated with respect to the third axis. Magnetic resonance diagnostic equipment. 3. The second high-frequency magnetic field applying means, wherein the first high-frequency magnetic field pulse and the second high-frequency magnetic field pulse are defined as n, wherein the spin-spin coupling constant between the first nuclide and the second nuclide is a positive number. (2n + 1) / (4 · J) before the echo time of the echo generated by the high frequency magnetic field pulse of
2. The magnetic resonance diagnostic apparatus according to claim 1, wherein a seventh high frequency magnetic field pulse for inversion is applied to the second nuclide after (2n + 1) / (4.J) after the high frequency magnetic field pulse. . 4. The apparatus according to claim 1, wherein the first high-frequency magnetic field applying means applies a sixth high-frequency magnetic field pulse for excitation to the first nuclide after the second high-frequency magnetic field pulse. Item 4. A magnetic resonance diagnostic apparatus according to Item 3. 5. The second high-frequency magnetic field applying means, wherein a spin-spin coupling constant between the first nuclide and the second nuclide, n is a positive number, and the first high-frequency magnetic field pulse and the second The fourth high frequency magnetic field is applied to the second nuclide after (2n + 1) / (2 · J) from the echo time of the echo generated by the high frequency magnetic field pulse. Magnetic resonance diagnostic equipment. 6. The second high-frequency magnetic field applying means alternately inverts the phase of the fourth high-frequency magnetic field pulse or the fifth high-frequency magnetic field pulse every time the first high-frequency magnetic field pulse is repeated. The magnetic resonance diagnostic apparatus according to claim 1, wherein: