CN114879109A - A magnetic resonance static magnetic field inhomogeneity compensation method, system and array module - Google Patents

Abstract

The application relates to a magnetic resonance static magnetic field inhomogeneity compensation method, system and array module, and relates to the field of magnetic resonance. The method includes acquiring current static magnetic field information of a current device; Find out the displayed difference and the position of the difference; adjust the initial position of the preset compensation coil according to the difference position; adjust the initial distribution density of the preset compensation coil according to the displayed difference. The present application has the advantages of increasing the array scale and spatial distribution density to increase the maximum spatial order achievable for shimming. The RF electromagnetic wave cannot generate effective induced current in the wire loop of the shim coil, so it is well isolated from the RF coil for magnetic resonance imaging, minimizes interference with each other, and improves the effect of convenient adjustment of the degree of freedom of the shim.

Description

A magnetic resonance static magnetic field inhomogeneity compensation method, system and array module

technical field

The present application relates to the field of magnetic resonance, and in particular, to a method, system and array module for compensating for inhomogeneity of a magnetic resonance static magnetic field.

Background technique

Magnetic resonance refers to the phenomenon of spin magnetic resonance.

In the related art, the traditional magnetic resonance static magnetic field inhomogeneity compensation method adopts a shimming basis based on spherical harmonic decomposition, and multiple shim coils respectively generate static magnetic fields corresponding to different spatial orders of spherical harmonic decomposition. The shim coils with different spatial orders generate static magnetic fields with different degrees of spatial variation, so as to compensate for the inhomogeneity of various static magnetic fields.

In view of the above-mentioned related technologies, the inventor believes that when the high-order shim coil is wound, it is necessary to accurately control the overall parameters, and the overall difficulty is great during the winding process, and the high-order shim coil is wound. The manufacturing bottleneck of shims limits the total number of shim coils, limits the degree of freedom of shims, and there is room for improvement.

SUMMARY OF THE INVENTION

In order to increase the array size and spatial distribution density, the maximum spatial order that can be achieved by shimming is increased. The radio frequency electromagnetic wave cannot generate effective induced current in the wire loop of the shim coil, so it is well isolated from the radio frequency coil for magnetic resonance imaging, minimizes interference with each other, improves the degree of freedom of the shim, and facilitates adjustment. The application provides a magnetic resonance static magnetic field Non-uniformity compensation method, system and array module.

In the first aspect, the present application provides a magnetic resonance static magnetic field inhomogeneity compensation method, which adopts the following technical solutions:

A magnetic resonance static magnetic field inhomogeneity compensation method, comprising:

Get the current static magnetic field information of the current device;

According to the current static magnetic field information, the display difference value and the difference value position are found from the preset display database;

Adjust the preset initial position of the compensation coil according to the difference position;

Adjust the preset initial distribution density of the compensation coils according to the displayed difference.

By adopting the above technical scheme, the displayed difference and the position of the difference are acquired by acquiring the current static magnetic field information, so as to judge the unclear display and the unclear position. The position and distribution density are adjusted to increase the array size and spatial distribution density to increase the maximum spatial order achievable for shimming. The RF electromagnetic wave cannot generate effective induced current in the wire loop of the shim coil, so it is well isolated from the RF coil for magnetic resonance imaging, minimizes interference with each other, and improves the degree of freedom of the shim for easy adjustment.

Optionally, the method for adjusting the position of the compensation coil includes:

According to the difference of the difference position, the position of the compensation coil is adjusted;

If the difference position is 0, no adjustment is performed;

If the difference position is not 0, find out the adjustment point from the preset position distribution database according to the difference position;

According to the adjustment point and the current magnetic field range information preset by the current compensation coil, a compensation coil is added to the adjustment point until the difference position is 0.

By adopting the above technical solution, when the position of the compensation coil is adjusted, the position difference value is calculated to judge whether the adjustment is made. When the difference value is not 0, it means that there is a problem in the position. , the position of the compensation coil is increased or decreased to meet the detection requirements.

Optionally, the repeated coverage of the current magnetic field range information of the compensation coil is judged to update the position of the adjustment point, and the method for updating the position of the adjustment point includes:

Determine whether the current magnetic field range information between adjacent compensation coils has an intersection;

If there is an intersection, adjust the current compensation coil to move in the direction of the adjustment point until the current magnetic field range information between adjacent compensation coils is tangent, and update the adjustment point;

If there is no intersection, adjust the current compensation coil to move toward the center of the compensation coil until the current magnetic field range information between adjacent compensation coils is tangent, and update the adjustment point.

By adopting the above technical solution, the tangent is controlled by judging the magnetic field range information between the compensation coils. Once there is an intersection or no intersection, the position of the compensation coils will be adjusted to adjust the adjustment point. To update, strong practicality.

Optionally, the method for adjusting the distribution density of the compensation coil includes:

Adjust the distribution density of the compensation coil according to the difference of the displayed difference;

If the displayed difference is 0, no adjustment is performed;

If the displayed difference is not 0, the density value is searched from the preset density distribution database according to the displayed difference;

According to the density value and the current magnetic field strength information preset by the current compensation coil, the maximum spatial order of the shimming of the compensation coil is replaced until the displayed difference value is 0.

By adopting the above technical solution, when judging the imaging situation, by judging the display difference, so as to understand whether the display is clear, and then control the magnetic field strength to adjust the maximum spatial order of the shimming of the compensation coil, Strong practicality.

Optionally, the adjustment method for replacing the compensation coil includes:

Find the spatial order value from the preset spatial order database according to the displayed difference;

Find out the first performance parameter of a single compensation coil from the preset compensation coil database according to the spatial order value;

Find out a single cost value from the preset cost database according to the first performance parameter;

Sort the individual cost values in reverse order to select the single compensation coil with the lowest cost value.

By adopting the above technical solution, the sizes of the compensation coils are different, and by understanding the first performance parameters of a single compensation coil, the single compensation coil with the lowest cost value can be found in the first performance parameters, thereby reducing the cost.

Optionally, the method for combining multiple compensation coils to replace a single compensation coil includes:

Find out the second performance parameter after the combination of the multiple compensation coils from the preset combination database according to the spatial order value;

Find out a plurality of cost values from the preset cost database according to the second performance parameter;

Arrange multiple cost values in reverse order to select multiple combined compensation coils with the lowest cost value;

Determine whether the single compensation coil with the lowest cost value is smaller than the multiple combined compensation coils with the lowest cost value;

If it is less than, select the single compensation coil with the lowest cost value;

If it is greater than or equal to, select multiple combined compensation coils with the lowest cost value.

By adopting the above technical solution, once a plurality of combined compensation coils can be used, a single compensation coil and a combined compensation coil are compared to screen out coils with low cost and consistent functions, which is highly practical.

Optionally, the method for generating the combined database of the current spatial order values includes:

According to the spatial order value, the compensation coil arrangement is tested in the preset simulation database to obtain the compensation coil arrangement;

The arrangement of compensation coils is classified into a group with the same number of compensation coils, and a group with the least number of compensation coils is selected;

The group with the least number of compensation coils is put into the combined database of the current spatial order values.

By adopting the above technical scheme, in the process of generating the combined database, by testing different combination arrangements, the arrangement of the compensation coils whose spatial order value meets the requirements is selected, thereby improving the combined database.

In the second aspect, the present application provides a magnetic resonance static magnetic field inhomogeneity compensation system, which adopts the following technical solutions:

A magnetic resonance static magnetic field inhomogeneity compensation system, comprising:

The acquisition module is used to acquire the current static magnetic field information of the current device;

The processing module is connected with the acquisition module, and is used for finding the displayed difference and the position of the difference from the preset display database according to the current static magnetic field information;

The judgment module is connected with the processing module, and is used to process and judge the information;

The judgment module adjusts the preset initial position of the compensation coil according to the difference value, and the judgment module adjusts the preset initial distribution density of the compensation coil according to the displayed difference value.

By adopting the above technical scheme, the displayed difference and the position of the difference are acquired by acquiring the current static magnetic field information, so as to judge the unclear display and the unclear position. The position and distribution density are adjusted to increase the array size and spatial distribution density to increase the maximum spatial order achievable for shimming. The RF electromagnetic wave cannot generate effective induced current in the wire loop of the shim coil, so it is well isolated from the RF coil for magnetic resonance imaging, minimizes interference with each other, and improves the degree of freedom of the shim for easy adjustment.

In a third aspect, the application provides an array module, which adopts the following technical solutions:

An array module is characterized by comprising a memory, a processor and a compensation coil, and a computer program capable of being loaded by the processor and executing the above method is stored in the memory.

By adopting the above technical scheme, the displayed difference and the position of the difference are acquired by acquiring the current static magnetic field information, so as to judge the unclear display and the unclear position. The position and distribution density are adjusted to increase the array size and spatial distribution density to increase the maximum spatial order achievable for shimming. The RF electromagnetic wave cannot generate effective induced current in the wire loop of the shim coil, so it is well isolated from the RF coil for magnetic resonance imaging, minimizes interference with each other, and improves the degree of freedom of the shim for easy adjustment.

To sum up, the present application includes at least one of the following beneficial technical effects:

1. Increase the array size and spatial distribution density to increase the maximum spatial order that can be achieved by shimming.

2. The RF electromagnetic wave cannot generate effective induced current in the wire loop of the shim coil, so it is well isolated from the RF coil for magnetic resonance imaging, minimizes interference with each other, and improves the degree of freedom of the shim for easy adjustment.

3. Reduce costs.

Description of drawings

Figure 1 is a schematic diagram of the structure of the compensation coil.

Figure 2 is a circuit schematic diagram of the compensation coil.

FIG. 3 is a flowchart of a method for compensating for inhomogeneity of a magnetic resonance static magnetic field.

FIG. 4 is a flow chart of a method for adjusting the position of the compensation coil.

FIG. 5 is a flow chart of a method for adjusting point position update.

FIG. 6 is a flow chart of a method for adjusting the distribution density of compensation coils.

FIG. 7 is a flowchart of an adjustment method for replacing a compensation coil.

Figure 8 is a flow chart of a method of combining multiple compensation coils to replace a single compensation coil.

FIG. 9 is a flowchart of a method for generating a combined database of current spatial order values.

Description of reference numerals: 1. coil body; 2. choke inductance; 3. output line; 4. circuit board; 5. input line; 6. filter circuit; 7. inductor; 8. capacitor; 9. compensation coil.

Detailed ways

In order to make the objectives, technical solutions and advantages of the present application clearer, the present application will be further described in detail below with reference to the accompanying drawings 1-9 and the embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application, but not to limit the present application.

The embodiment of the present application discloses a method for compensating the inhomogeneity of a magnetic resonance static magnetic field, which improves the array scale and spatial distribution density to increase the achievable maximum spatial order of the shimming. The RF electromagnetic wave cannot generate effective induced current in the wire loop of the shim coil, so it is well isolated from the RF coil for magnetic resonance imaging, minimizes interference with each other, and improves the degree of freedom of the shim for easy adjustment.

Referring to FIG. 1 , the compensation coil 9 includes a coil body 1 , which is wound with enameled wire. The diameter of the coil body 1 can be adjusted according to the actual length, and can be adjusted by the staff according to needs, which will not be repeated here.

The coil body 1 is also provided with a choke inductance 2 in series, at least one choke inductance 2 is provided, and the resonance frequency of the choke inductance 2 is consistent with the magnetic resonance Larmor frequency, and as the circumference of the coil body 1 increases, The spacing between the choke inductors 2 is <1/2 the wavelength of the magnetic resonance radio frequency.

Two separate output wires 3 are welded on both ends of the coil body 1, and the output wires 3 are wires covered with plastic sheaths to isolate signals; the two output wires 3 are intertwined with each other to eliminate interference. The side of the output line 3 away from the coil body 1 is also welded with a circuit board 4, and at least one circuit board 4 is provided, and the circuit board 4 is added according to the actual situation. It is connected through another output line 3.

The end of the circuit board 4 away from the choke inductor 2 is also connected with an input line 5 for inputting direct current. The input line 5 also uses a wire covered with a plastic sheath, and the two input lines 5 are intertwined with each other to eliminate interference.

The circuit board 4 includes a set of filter circuits 6 . There can also be multiple groups of filter circuits 6, and multiple groups of filter circuits 6 are connected in series with each other, that is, multiple circuit boards 4 are used in series with each other.

Referring to FIG. 2 , this embodiment is disclosed by taking two groups of circuit boards 4 and three groups of choke inductors 2 as examples. When multiple groups of filter circuits 6 or choke inductors 2 are used, the working principle and connection method are the same. The connection method is the common knowledge of those skilled in the art, and will not be repeated here.

And the compensation coil 9 is used as a unit, and the unit is used as a matrix point, and multiple units are used for cooperation, so as to piece together the required array coils for use.

Referring to FIG. 3 , the inhomogeneity of various static magnetic fields will be compensated by combining individual compensation coils 9 in an array instead of driving a plurality of shim coils with different spatial orders to generate static magnetic fields with different degrees of spatial variation. method of sex.

A magnetic resonance static magnetic field inhomogeneity compensation method, comprising the following steps:

Step 100: Acquire current static magnetic field information of the current device.

When the device is in use, the current static magnetic field information is acquired through the sensor, so as to obtain the image information generated by the magnetic resonance, and the compensation coil 9 is adjusted according to the quality of the generated image information until the generated image information clear.

Step 101 : Find the display difference and the position of the difference from a preset display database according to the current static magnetic field information.

The display database is a preset database, and has different display standards for images of different parts, and is pre-collected and entered into the display database by the staff for later image comparison.

Through the display image corresponding to the static magnetic field information, the display difference value and the difference value position are searched from the display database.

To display the difference value, it needs to reach the difference value that needs to be clearly displayed. By comparing the image with the preset data, the calculated value is obtained. When calculating, compare the clarity of its display, and once there is a display, calculate the difference according to the clear light and dark degree and the preset light and dark ratio. When there is no display, but here it needs to be displayed, directly adjust the ratio to the maximum value.

The difference position is the position that needs to be displayed, and there should be an image to display. At this time, no image display is performed. At this time, the image is not clear due to interference. Therefore, the difference position is calculated for the position. When calculating the position, the preset positioning point is used to determine the positioning point that needs to be displayed but is not displayed.

Step 102: Adjust the preset initial position of the compensation coil 9 according to the difference position.

By knowing the position of the difference, the preset position of the compensation coil 9 is adjusted.

4, when the position of the compensation coil 9 is adjusted, the position adjustment method includes the following steps:

Step 200: Perform position adjustment on the position of the compensation coil 9 according to the difference of the difference positions.

The position of the compensation coil 9 is adjusted by the difference of the obtained difference positions. When adjusting, the difference position is first judged.

Step 201: If the difference position is 0, no adjustment is performed.

If the difference position is 0, it means that the current position is accurate and there is a correct image to calculate, so no adjustment is made.

Step 202: If the difference value position is not 0, find out the adjustment point from the preset position distribution database according to the difference value position.

If the difference position is not 0, that is, greater than 0 or less than 0, it means that there is an offset, so the position of the compensation coil 9 needs to be adjusted, and the adjustment point is found from the position distribution database according to the difference position.

The location distribution database is a preset database, and the location database is determined by the staff according to the size of the detected picture, so as to confirm the location of the adjustment point.

Step 203 : according to the adjustment point and the current magnetic field range information preset by the current compensation coil 9 , add a compensation coil 9 to the adjustment point until the difference position is 0.

For each different compensation coil 9, there is different current magnetic field range information. Through the understanding of the magnetic field range information, the compensation coil 9 is added to the adjustment point until the difference position is 0, so as to meet the detection requirements.

With reference to FIG. 5 , the repeated coverage of the current magnetic field range information of the compensation coil 9 is judged to update the position of the adjustment point. The method for updating the position of the adjustment point includes the following steps:

Step 300 : Determine whether the current magnetic field range information between adjacent compensation coils 9 has an intersection.

Judging the intersection of the compensation coils 9, thereby reducing the overall waste of the compensation coils 9 due to overlapping, and also reducing the problem of unclear display caused by the too wide distribution of the compensation coils 9. Therefore, between adjacent compensation coils 9 Whether there is an intersection of the current magnetic field range information is judged.

Step 301 : If there is an intersection, adjust the current compensation coil 9 to move in the direction of the adjustment point until the current magnetic field range information between adjacent compensation coils 9 is tangent, and update the adjustment point.

Since the effective range covered by the magnetic field range information is limited, the effective range of the magnetic field range information is selected to confirm the boundary.

Once the current magnetic field range information between adjacent compensation coils 9 has an intersection, adjust the current compensation coil 9 to move toward the adjustment point until the current magnetic field range information between adjacent compensation coils 9 is tangent, and update the adjustment point.

Step 302 : If there is no intersection, adjust the current compensation coil 9 to move toward the center of the compensation coil 9 until the current magnetic field range information between adjacent compensation coils 9 is tangent, and update the adjustment point.

Once the current magnetic field range information between adjacent compensation coils 9 does not intersect, adjust the current compensation coil 9 to move toward the center of the compensation coil 9 until the current magnetic field range information between adjacent compensation coils 9 is tangent, and update the adjustment point.

Referring to FIG. 3 , step 103 : adjust the preset initial distribution density of the compensation coil 9 according to the displayed difference.

By understanding the displayed difference, the preset initial distribution density of the compensation coil 9 is adjusted to improve the clarity.

6 , the method for adjusting the distribution density of the compensation coil 9 includes the following steps:

Step 400: Adjust the distribution density of the compensation coil 9 according to the difference of the displayed difference.

The distribution density of the compensation coil 9 is adjusted according to the difference of the displayed difference, so as to adjust the displayed state.

Step 401: If the displayed difference value is 0, no adjustment is performed.

If the displayed difference value is 0, it means that the current position is clearly displayed and there is a clear enough image for calculation, so no adjustment is made.

Step 402: If the displayed difference value is not 0, search for the density value from the preset density distribution database according to the displayed difference value.

If the display position is not 0, that is, greater than 0 or less than 0, it means that the image is not clear enough or even ghosting occurs. Therefore, it is necessary to adjust the distribution density of the compensation coil 9 to improve the clarity of the image.

The density value is found from the density distribution database by displaying the difference value, wherein the density distribution database is preset data, and the data is collected and entered by the staff to improve it. Density values can be matched by evaluating the difference in display.

Step 403 : Replace the maximum spatial order of the shimming of the compensation coil 9 according to the density value and the current magnetic field strength information preset by the current compensation coil 9 until the displayed difference value is 0.

Each compensation coil 9 has its own magnetic field strength information. According to the matched density value and the current magnetic field strength information of the current compensation coil 9, the maximum spatial order of the shimming of the compensation coil 9 is replaced until the displayed difference value is 0.

7 , when the compensation coil 9 needs to be replaced, the adjustment method for replacing the compensation coil 9 includes the following steps:

Step 500: Find the spatial order value from the preset spatial order database according to the displayed difference value.

According to the matched display difference value, the spatial order value is searched from the preset spatial order database. The spatial order database is a preset database, which is entered and set by the staff, and will not be repeated here.

Step 501: Find out the first performance parameter of a single compensation coil 9 from the preset compensation coil 9 database according to the spatial order value.

According to the found spatial order value, the first performance parameter of a single compensation coil 9 is searched from the compensation coil 9 database, wherein the compensation coil 9 database is a preset database, and is entered and set by the staff. Do repeat.

Since the first performance parameter of the single compensation coil 9 will be changed according to the material and the value and number of the capacitance and inductance, the performance parameter will be changed, so it is adjusted.

Step 502: Find out a single cost value from a preset cost database according to the first performance parameter.

According to the required first performance parameter, a single cost value is found from the cost database, wherein the cost database is a preset database, and compensation coils 9 with different costs can be matched with the required first performance parameter.

Step 503: Arrange the individual cost values in reverse order to select the single compensation coil 9 with the lowest cost value.

Under the condition that the first performance parameter is satisfied, the single compensating coil 9 with the lowest cost value is selected by arranging the individual cost values in reverse order, so as to reduce the overall cost.

Referring to FIG. 8 , when the cost of a single compensation coil 9 increases, a single compensation coil 9 can be replaced by a combination of multiple compensation coils 9 . The method of combining a plurality of compensation coils 9 to replace a single compensation coil 9 includes the following steps:

Step 600 : Find the second performance parameter after the combination of the plurality of compensation coils 9 from the preset combination database according to the spatial order value.

The combination database is a preset database, and the data is imported by the staff, which will not be repeated here. Under the condition that the spatial order value remains unchanged, the second performance parameter after the combination of the multiple compensation coils 9 is searched from the combination database according to the spatial order value.

Step 601: Find out a plurality of cost values from a preset cost database according to the second performance parameter.

Wherein, the cost database is preset data, and a plurality of cost values are searched out from the cost database according to the second performance parameter combined by the plurality of compensation coils 9 .

Step 602: Arrange the multiple cost values in reverse order to select multiple combined compensation coils 9 with the lowest cost value.

Under the condition that the second performance parameter is satisfied, the multiple cost values are arranged in reverse order, so as to select multiple combined compensation coils 9 with the lowest cost value.

Step 603: Determine whether the single compensation coil 9 with the lowest cost value is smaller than the multiple combined compensation coils 9 with the lowest cost value.

The cost between a single compensation coil 9 with the lowest cost value and a plurality of combined compensation coils 9 with the lowest cost value is judged, so as to select a plurality of combined compensation coils 9 or a single compensation coil 9 .

Step 604: If it is less than the value, select the single compensation coil 9 with the lowest cost value.

When the single compensation coil 9 with the lowest cost value is smaller than the multiple combined compensation coils 9 with the lowest cost value, the single compensation coil 9 with the lowest cost value is selected for use.

Step 605: If it is greater than or equal to, select multiple combined compensation coils 9 with the lowest cost value.

When the single compensation coil 9 with the lowest cost value is greater than or equal to the multiple combined compensation coils 9 with the lowest cost value, the multiple combined compensation coils 9 with the lowest cost value are selected, thereby improving the overall stability.

Referring to Fig. 9, the generation method of the combined database of the current spatial order value comprises the following steps:

Step 700 : Experiment with the arrangement of the compensation coils 9 in the preset simulation database according to the spatial order value to obtain the arrangement of the compensation coils 9 .

According to the found spatial order value, the compensation coil 9 arrangement is tested in the simulation database, wherein the simulation database is the preset data, and the simulation database has the ability of active learning, and the internal program is set by the staff. This will not be repeated.

Therefore, the arrangement mode of the compensation coils 9 is obtained from the simulation database, and the arrangement mode of the compensation coils 9 may be parallel, overlapping, or intersecting.

Step 701 : The arrangement of the compensation coils 9 is classified into a group with the same number of compensation coils 9 , and a group with the least number of compensation coils 9 is selected.

Taking the same number of compensation coils 9 as a group, the arrangement of the compensation coils 9 is classified, and a group with the least number of compensation coils 9 is selected from the group, that is, the group with the lowest cost.

Step 702: The group with the least number of compensation coils 9 is placed in the combined database of the current spatial order values.

In a group with the smallest number of compensation coils 9, there may be multiple combinations, and at this time, this group of compensation coils 9 is put into the combination database of the current spatial order value, so as to facilitate debugging.

Based on the same inventive concept, an embodiment of the present invention provides a magnetic resonance static magnetic field inhomogeneity compensation system, including:

The acquisition module is used to acquire the current static magnetic field information of the current device;

The processing module is connected with the acquisition module, and is used for finding the displayed difference and the position of the difference from the preset display database according to the current static magnetic field information;

The judgment module is connected with the processing module, and is used to process and judge the information;

The judgment module adjusts the preset initial position of the compensation coil 9 according to the difference value, and the judgment module adjusts the preset initial distribution density of the compensation coil 9 according to the displayed difference value.

Those skilled in the art can clearly understand that, for the convenience and conciseness of the description, only the division of the above-mentioned functional modules is used as an example. The internal structure of the device is divided into different functional modules to complete all or part of the functions described above. For the specific working process of the system, apparatus and unit described above, reference may be made to the corresponding process in the foregoing method embodiments, and details are not described herein again.

Based on the same inventive concept, an embodiment of the present invention provides an array module, including a memory, a processor and a compensation coil 9, where the memory stores a computer program that can be loaded by the processor and executes a method for compensating for the inhomogeneity of the magnetic resonance static magnetic field.

Those skilled in the art can clearly understand that, for the convenience and conciseness of the description, only the division of the above-mentioned functional modules is used as an example. The internal structure of the device is divided into different functional modules to complete all or part of the functions described above. For the specific working process of the system, apparatus and unit described above, reference may be made to the corresponding process in the foregoing method embodiments, and details are not described herein again.

The above are all preferred embodiments of the present application, which are not intended to limit the protection scope of the present application. Any feature disclosed in this specification (including the abstract and drawings), unless otherwise specified, may be equivalent to other or have similar Replacement features of the purpose. That is, unless expressly stated otherwise, each feature is but one example of a series of equivalent or similar features.

Claims (9)

1. a magnetic resonance static magnetic field inhomogeneity compensation method, is characterized in that, comprises: Get the current static magnetic field information of the current device; According to the current static magnetic field information, the display difference value and the difference value position are found from the preset display database; Adjust the preset initial position of the compensation coil (9) according to the difference position; The initial distribution density of the preset compensation coil (9) is adjusted according to the displayed difference. 2 . The method for compensating the inhomogeneity of the magnetic resonance static magnetic field according to claim 1 , wherein the method for adjusting the position of the compensation coil ( 9 ) comprises: 3 . According to the difference of the difference position, the position of the compensation coil (9) is adjusted; If the difference position is 0, no adjustment is performed; If the difference position is not 0, find out the adjustment point from the preset position distribution database according to the difference position; According to the adjustment point and the current magnetic field range information preset by the current compensation coil (9), a compensation coil (9) is added to the adjustment point until the difference position is 0. 3 . The method for compensating for the inhomogeneity of the magnetic resonance static magnetic field according to claim 2 , wherein: judging the repeated coverage of the current magnetic field range information of the compensation coil ( 9 ) to determine the position of the adjustment point. 4 . Update, the method of adjusting the point position update includes: Determine whether the current magnetic field range information between adjacent compensation coils (9) has an intersection; If there is an intersection, adjust the current compensation coil (9) to move in the direction of the adjustment point until the current magnetic field range information between adjacent compensation coils (9) is tangent, and update the adjustment point; If there is no intersection, adjust the current compensation coil (9) to move toward the center of the compensation coil (9) until the current magnetic field range information between adjacent compensation coils (9) is tangent, and update the adjustment point. The method for compensating for the inhomogeneity of the magnetic resonance static magnetic field according to claim 1, wherein the method for adjusting the distribution density of the compensation coil (9) comprises: Adjust the distribution density of the compensation coil (9) according to the difference of the displayed difference; If the displayed difference is 0, no adjustment is performed; If the displayed difference is not 0, the density value is searched from the preset density distribution database according to the displayed difference; According to the density value and the current magnetic field strength information preset by the current compensation coil (9), the maximum spatial order of the shimming of the compensation coil (9) is replaced until the displayed difference value is 0. 5. The method for compensating for the inhomogeneity of the magnetic resonance static magnetic field according to claim 4, wherein the adjustment method for replacing the compensation coil (9) comprises: Find the spatial order value from the preset spatial order database according to the displayed difference; Find out the first performance parameter of the single compensation coil (9) from the preset compensation coil (9) database according to the spatial order value; Find out a single cost value from the preset cost database according to the first performance parameter; Sort the individual cost values in reverse order to select the single compensation coil with the lowest cost value (9). 6. The method for compensating for the inhomogeneity of the magnetic resonance static magnetic field according to claim 5, wherein the method for combining a plurality of compensation coils (9) to replace a single compensation coil (9) comprises: Find out the second performance parameter after the combination of the plurality of compensation coils (9) from the preset combination database according to the spatial order value; Find out a plurality of cost values from the preset cost database according to the second performance parameter; Arrange multiple cost values in reverse order to select multiple combined compensation coils with the lowest cost value (9); Determine whether the single compensation coil (9) with the lowest cost value is smaller than the multiple combined compensation coils (9) with the lowest cost value; If it is less than, select the single compensation coil (9) with the lowest cost value; If it is greater than or equal to, select multiple combined compensation coils (9) with the lowest cost value. 7. A magnetic resonance static magnetic field inhomogeneity compensation method according to claim 6, characterized in that: the generation method of the combined database of the current spatial order value comprises: According to the spatial order value, the compensating coil (9) arrangement is tested in the preset simulation database to obtain the compensating coil (9) arrangement; The arrangement of the compensation coils (9) is classified into a group with the same number of compensation coils (9), and a group with the least number of compensation coils (9) is selected; The group with the least number of compensation coils (9) is put into the combined database of current spatial order values. 8. A magnetic resonance static magnetic field inhomogeneity compensation system, characterized in that, comprising: The acquisition module is used to acquire the current static magnetic field information of the current device; The processing module is connected with the acquisition module, and is used for finding the displayed difference and the position of the difference from the preset display database according to the current static magnetic field information; The judgment module is connected with the processing module, and is used to process and judge the information; The judgment module adjusts the preset initial position of the compensation coil (9) according to the difference value, and the judgment module adjusts the preset initial distribution density of the compensation coil (9) according to the displayed difference value. 9. An array module, characterized by comprising a memory, a processor and a compensation coil (9), wherein the memory stores a computer program capable of being loaded by the processor and executing the method according to any one of claims 1 to 7.

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