CN104880683B - A kind of detection means of the shimming piece of magnetic resonance imaging system, method and system - Google Patents
A kind of detection means of the shimming piece of magnetic resonance imaging system, method and system Download PDFInfo
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- CN104880683B CN104880683B CN201410070563.8A CN201410070563A CN104880683B CN 104880683 B CN104880683 B CN 104880683B CN 201410070563 A CN201410070563 A CN 201410070563A CN 104880683 B CN104880683 B CN 104880683B
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Abstract
Embodiment of the present invention discloses a kind of detection means of the shimming piece of magnetic resonance imaging system, method and system.Detection means includes：Magnetic filed generation unit, for producing magnetic field；Magnetic flux amount detection unit, for detecting shimming piece magnetic flux caused by the magnetic field saturated magnetization；Computing unit, for determining the number of the shimming piece based on the magnetic flux.Shimming piece based on quantitative number can produce the magnetic flux proportional to the quantitative number, embodiment of the present invention by detect shimming piece be saturated magnetization caused by magnetic flux verify shimming piece number automatically, without manually checking checking, operating efficiency is significantly improved.
Description
Technical field
The present invention relates to mr imaging technique field, more particularly to a kind of inspection of the shimming piece of magnetic resonance imaging system
Survey device, method and system.
Background technology
Magnetic resonance imaging (Magnetic Resonance Imaging, MRI) is with computer technology, electronic circuit skill
Art, superconduction body technique development and a kind of biomagnetism nuclear spin imaging technique for developing rapidly.It is using magnetic field with penetrating
Frequency pulse makes the proton (i.e. H+) of precession in tissue that vibration generation radiofrequency signal occur, and handles and is imaged through computer.When
Object is placed in magnetic field, with appropriate electromagnetic wave irradiation it, be allowed to resonate, then analyze it discharge electromagnetic wave, so that it may
To learn the nuclear position and the species that are formed this object, the accurate stereo-picture of interior of articles can be depicted as accordingly.
Such as the animation for the serial section that can be obtained by MRI scan human brain, by the crown, until
Foot.
The magnetic field homogeneity of magnetic resonance system is the basic demand of magnetic resonance imaging.Due to magnet generation error and magnet
The influence of installation environment, field homogeneity is difficult in itself by magnet merely.Therefore need to perform various shimming operations, to protect
Card is enough the magnetic field homogeneity for realizing magnetic resonance imaging.For example respective counts can be arranged at the diverse location of magnetic resonance system
Purpose shimming piece (being typically ferrous material) is calculated with compensating magnetic field non-uniformity wherein magnetic field planning can be based on by computer
Go out particular location and corresponding shimming piece number.
At present, installation personnel is manually checked at each shimming piece position according to shimming result of calculation and arranges phase
Answer the shimming piece of number.The time is not only expended however, manually checking, and is easily malfunctioned, and if shimming piece quantity is not right, then
Multiple shimming can be caused, (shimming process needs magnet to lift field, this process so as to increase the consumption of set-up time and liquid helium
Consume liquid helium).In addition, when shimming piece is packaged into shimming box, if installation personnel do not open shimming box also can not be clear
Point shimming piece number.
The content of the invention
Embodiment of the present invention proposes a kind of detection means of the shimming piece of magnetic resonance imaging system, to improve work effect
Rate.
Embodiment of the present invention proposes a kind of detection method of the shimming piece of magnetic resonance imaging system, to improve work effect
Rate.
Embodiment of the present invention proposes a kind of detecting system of the shimming piece of magnetic resonance imaging system, to improve work effect
Rate.
The technical scheme of embodiment of the present invention is as follows：
A kind of shimming piece detection means of magnetic resonance imaging system, including：
One magnetic filed generation unit, for producing a magnetic field；
One magnetic flux amount detection unit, for detecting shimming piece magnetic flux caused by the magnetic field saturated magnetization；
One computing unit, for determining the number of the shimming piece based on the magnetic flux.
The magnetic filed generation unit includes a field-generating coil.
The magnetic flux amount detection unit includes a flux sensing coil and a fluxmeter.
The flux sensing coil and the field-generating coil form a self coupling coil.
The computing unit, is used for：
Based on the unit magnetic flux and the magnetic flux pre-set, the number of the shimming piece is determined；And/or
When the difference between the magnetic flux and a calculating magnetic flux of setting number shimming piece is more than one pre-set
During threshold value, judge that the number of the shimming piece is wrong, and/or when the magnetic flux is with setting the one of number shimming piece to calculate magnetic
When difference between flux is less than the threshold value pre-set, judge that the number of the shimming piece is correct.
A kind of detection method of the shimming piece of magnetic resonance imaging system, including：
Produce a magnetic field；
Detect shimming piece magnetic flux caused by the magnetic field saturated magnetization；
The number of the shimming piece is determined based on the magnetic flux.
This method includes：
Based on the unit magnetic flux and the magnetic flux pre-set, the number of the shimming piece is determined；And/or
When the difference between the magnetic flux and a calculating magnetic flux of setting number shimming piece is more than one pre-set
During threshold value, judge that the number of the shimming piece is wrong, and/or when the magnetic flux and the calculating for setting the shimming piece of number one
When difference between magnetic flux is less than the threshold value pre-set, judge that the number of the shimming piece is correct.
A kind of shimming piece detecting system of magnetic resonance imaging system, including the as above detection dress of any described shimming piece
Put.
It can be seen from the above technical proposal that in the shimming piece detection means of embodiment of the present invention, magnetic field produces single
Member, for producing magnetic field；Magnetic flux amount detection unit, for detecting shimming piece magnetic flux caused by the magnetic field saturated magnetization
Amount；Computing unit, for determining the number of shimming piece based on the magnetic flux.As can be seen here, the shimming piece based on quantitative number can
To produce the magnetic flux proportional to the quantitative number, when embodiment of the present invention can be saturated magnetization by detecting shimming piece
Caused magnetic flux verifies shimming piece number automatically, without manually checking checking, so as to significantly improve operating efficiency.
Moreover, in shimming piece in the case of packed, embodiment of the present invention still can verify shimming with auto inventory
Piece number, also improves the scope of application.
Further, embodiment of the present invention, so as to avoid multiple shimming problem, can be reduced with accurate validation shimming piece quantity
Set-up time, and saved liquid helium.
Brief description of the drawings
Fig. 1 is the structure of the detecting device figure according to the shimming piece of embodiment of the present invention magnetic resonance imaging system.
Fig. 2 is the detection method flow chart of the shimming piece of embodiment of the present invention magnetic resonance imaging system.
Fig. 3 is the shimming piece detecting system structure chart of the magnetic resonance imaging system of embodiment of the present invention.
Fig. 4 is according to embodiment of the present invention, the shimming piece detecting system structure chart of magnetic resonance imaging system.
Embodiment
In order that technical scheme and advantage are more clearly understood, below in conjunction with drawings and the embodiments, to this
Invention is further elaborated.It should be appreciated that embodiment described herein only illustrates this to illustrative
Invention, the protection domain being not intended to limit the present invention.
It is succinct and directly perceived in order to what is described, hereafter by describing some representational embodiments come the side to the present invention
Case is illustrated.Substantial amounts of details is only used for help and understands the solution of the present invention in embodiment.However, it will be apparent that the present invention
Technical scheme can be not limited to these details when realizing.In order to avoid unnecessarily having obscured the solution of the present invention, some realities
Apply mode not described meticulously, but only give framework.Hereinafter, " comprising " refers to " include but is not limited to ", " root
According to ... " refer to " according at least to ..., but be not limited to according only to ... ".Due to the speech habits of Chinese, hereinafter without spy
When not pointing out the quantity of composition, it is meant that it can also be multiple that the composition, which can be one, or can be regarded as at least one.
In view of manually checking many defects of shimming piece, embodiment of the present invention proposes a kind of shimming piece detection of automation
Technical scheme.
In magnetic resonance arts, shimming piece is generally made up of the material with high magnetic permeability, and shimming piece usually can
Significantly change magnetic flux.When shimming piece is saturated magnetization, the shimming piece of quantitative number can produce with the quantitative number into than
The magnetic flux of example.Therefore, it is even to verify can be magnetized caused magnetic flux based on shimming piece for embodiment of the present invention
The number validity of field piece.
Fig. 1 is the structure of the detecting device figure according to the shimming piece of the magnetic resonance imaging system of embodiment of the present invention.
Based on the detection means, the number validity of multiple shimming pieces can be detected, regardless of whether these shimming pieces are superpositions
Together, or each discrete placement.
As shown in figure 1, the device 100 includes magnetic filed generation unit 101 and magnetic flux amount detection unit 102, wherein：
Magnetic filed generation unit 101, for producing magnetic field；
Magnetic flux amount detection unit 102, for detecting shimming piece magnetic flux caused by the magnetic field saturated magnetization.
Magnetic filed generation unit 101 can produce magnetic field in several ways.
It is well known that magnetic field is as caused by moving charge or electric current.Preferably, magnetic filed generation unit 101 can pass through
Direct current produces magnetostatic field, consequently facilitating subsequently calculating magnetic flux and the validation verification of shimming piece number.Magnetic field produces single
Magnetostatic field caused by member 101 causes each shimming piece all magnetic saturation within the magnetic field range.Alternatively, magnetic field produces single
Member 101 can also by alternating current produce alternating magnetic field, and the alternating magnetic field cause it is each within the magnetic field range
The all magnetic saturation of shimming piece.
In one embodiment：
Magnetic filed generation unit 101 includes a field-generating coil, and the field-generating coil winds each shimming piece, preferably should
Field-generating coil is connected with dc source.The dc source provides direct current to field-generating coil, so as to which magnetic field produces
Coil can produce magnetostatic field.Alternatively, the field-generating coil is connected with AC power.The AC power produces to magnetic field
Coil provides alternating current, so as to which field-generating coil can produce alternating magnetic field.
Each shimming piece magnetizes under magnetic fields produced by magnetic filed generation unit 101.With the institute of magnetic filed generation unit 101
The gradual increase of magnetic field intensity is produced, the intensity of magnetization of shimming piece also constantly increases；The magnetic field produced by magnetic filed generation unit 101
Increase to after some strength, the intensity of magnetization of each shimming piece just stop increasing and be maintained at one it is stable numerically, this
When each shimming piece reached saturated magnetization state.
, can after the magnetization characteristic (such as magnetic conductivity, magnetization curve, saturation magnetization, etc.) of shimming piece is determined
To determine the magnetic field intensity needed for the saturated magnetization shimming piece.It can determine to produce magnetic saturation shimming based on the magnetic field intensity
Current parameters required for the magnetic field of piece.Electric current is provided to magnetic filed generation unit 101 so that magnetic based on the current parameters of the determination
Magnetic field caused by electric field generating unit 101 being capable of saturated magnetization shimming piece.
In one embodiment：
Magnetic flux amount detection unit 102 includes a flux sensing coil and a fluxmeter, flux sensing coil winding
Shimming piece.Shimming piece magnetic flux caused by the saturated magnetization of magnetic field, i.e. shimming piece can be detected by flux sensing coil
The magnetic flux as caused by shimming piece magnetic field is saturated after magnetization, and the Specific amounts of the magnetic flux can be measured by fluxmeter
Change value.
Flux sensing coil and field-generating coil can be separate coils, and its coil turn and sectional area were both
It can be the same or different.Moreover, flux sensing coil and field-generating coil can also form self coupling coil, i.e. magnetic flux
The part that detection coil is field-generating coil is measured, or the part that field-generating coil is flux sensing coil.This hair
Bright embodiment is to this and is not limited.
When shimming piece is saturated magnetization, the shimming piece of quantitative number can produce the magnetic flux proportional to the quantitative number
Amount.Therefore, specifically determined by the magnetic flux detected to magnetic flux amount detection unit 102, multiple shimming pieces can be verified
Number validity.
The device also includes：
Computing unit 103, the number of shimming piece is determined for the magnetic flux based on the measurement.
For example the specific quantized value of the magnetic flux by various types of fluxmeters, can be measured.
Exemplarily, magnetic flux amount detection unit 102 can include magneto-electric fluxmeter.Magneto-electric fluxmeter is that one kind does not have
The permanent magnet moving coil galvanometer of torque is revolted, the pointer that its moving part is driven can rest on the optional position on scale, and work
Make in extreme overdamping state.When in use, its moving-coil and external magnetic flux search coil are connected.Closed when search coil institute chain
When magnetic flux changes, induced electromotive force is produced in coil, the pointer of fluxmeter is deflected into new position by origin-location (α 1)
(α 2), the difference (Δ α=α 2- α 1) of two positions is proportional to the time integral of induced electromotive force, so as to the also change with magnetic flux
Δ φ is proportional.Adjustment mechanism can be housed on magneto-electric fluxmeter, can before reading by pointer zero setting or other be easy to
The position of reading.
Exemplarily, magnetic flux amount detection unit 102 can include electronic type fluxmeter.Electronic type fluxmeter can be by electronics
Formula integrator forms with indicating meter.Integrator integrated amplifier adds capacitance-resistance feedback to form, and indication electric meter can be mechanical
Indication electric meter or digital voltmeter.As the flux change Δ φ that institute's chain closes in search coil, electricity is induced in coil
Kinetic potential e, now, (wherein n is the number of turn of search coil to output voltage e0=-n* Δs φ/RC of integrator；R is resistance；C is product
Divide electric capacity), the variable quantity with the magnetic flux of search coil phase chain conjunction can be read from indication electric meter.
Exemplarily, magnetic flux amount detection unit 102 can include digital integration formula fluxmeter.Digital integration formula fluxmeter by
Frequency to voltage converter is formed with counter.The voltage e that flux change Δ φ in search coil is inducted, by voltage-frequency
Converter is converted to pulse train, and its repetition rate is directly proportional to e values at different moments.Counter makees tale to pulse train, always
It is directly proportional to Δ φ to count N, so as to obtain the variable quantity of magnetic flux.
The specific implementation form of fluxmeter described in detail above, it will be appreciated by those of skill in the art that this citing
Only it is exemplary, is not used to form restriction to the protection domain of embodiment of the present invention.
Computing unit 103 is the intelligent terminal with data-handling capacity, including but not limited to computer, work station, clothes
Business device, the even smart mobile phone of some excellent performances, palm PC, tablet personal computer etc..It can be installed on these intelligent terminals
There is operating system, include but is not limited to：Windows operating system, LINUX operating systems, Android operation system, Symbian
Operating system, Windows mobile operating systems and iOS operating systems etc..
Enumerate the particular type of some intelligent terminals and specific OS Type in detail above, but this area skill
Art personnel are it is to be appreciated that embodiment of the present invention is not limited to the above-mentioned type enumerated, and can be applicable to other
Among the intelligent terminal type and OS Type of meaning.
The actual magnetic flux measured of fluxmeter generally includes magnetic field produced by air-gap flux amount, magnetic filed generation unit 101
Magnetic flux and shimming piece produced by magnetic filed generation unit 101 magnetic field magnetization caused by magnetic flux.Wherein, air-gap flux
The magnetic flux in magnetic field produced by amount and magnetic filed generation unit 101 is known, therefore can be based on that fluxmeter is actual to be measured
Magnetic flux determine shimming piece produced by magnetic filed generation unit 101 magnetic field magnetization caused by magnetic flux.
In order to describe simplicity, below by magnetic flux caused by the magnetic field magnetization produced by magnetic filed generation unit 101 of shimming piece
Amount is described as the magnetic flux of fluxmeter measurement.
In one embodiment：
Computing unit 103, for the magnetic flux that is measured when fluxmeter, (i.e. shimming piece is produced by magnetic filed generation unit 101
Magnetic flux caused by the magnetization of magnetic field) and set the difference that calculates magnetic flux between of the number shimming piece under magnetic saturation state big
When the threshold value pre-set, assert that the actual number of shimming piece is not consistent with the setting number, therefore, it is determined that shimming piece
Number is wrong, and/or, when the measurement magnetic flux and set between calculating magnetic flux of the number shimming piece under magnetic saturation state
Difference be less than pre-set threshold value when, then assert shimming piece actual number be consistent with the setting number, therefore, it is determined that
The number of shimming piece is correct.
In one embodiment：
Computing unit 103, for the magnetic flux based on the unit magnetic flux that pre-sets and measurement, determine the number of shimming piece
Mesh.Herein, setting unit shimming piece is saturated caused magnetic flux, i.e. unit magnetic flux during magnetization first；Then will survey
The magnetic flux of amount divided by the unit magnetic flux, you can to obtain the specific number of shimming piece.
Embodiment of the present invention can be embodied as diversified forms.For example it can be specifically embodied as a kind of hold and set
It is standby, consequently facilitating carrying out the checking of shimming piece number in the erecting bed of magnetic resonance imaging system.
Based on above-mentioned labor, embodiment of the present invention also proposed a kind of shimming chip detection method.
Fig. 2 is the detection method flow chart according to the shimming piece of the magnetic resonance imaging system of embodiment of the present invention.
As shown in Fig. 2 this method includes：
Step S201：Produce magnetic field.
Herein, magnetostatic field can be produced by direct current, consequently facilitating subsequently being tested for the validity of shimming piece number
Card, and caused magnetostatic field can cause multiple shimming piece all magnetic saturation within the magnetic field range.Alternatively, may be used also
To produce alternating magnetic field by alternating current, and the alternating magnetic field causes multiple shimming pieces all magnetic within the magnetic field range
Saturation.
Step S202：Detect shimming piece magnetic flux caused by the magnetic field saturated magnetization.
When shimming piece is saturated magnetization, the shimming piece of quantitative number can produce the magnetic flux proportional to the quantitative number
Amount.Therefore, caused magnetic flux can be magnetized based on shimming piece to verify the number validity of multiple shimming pieces.
This method also includes：
Step S203：Measure the magnetic flux of detection；
Step S204：Magnetic flux based on the measurement determines the number of shimming piece.
In one embodiment, when the magnetic flux of measurement and the difference calculated between magnetic flux of setting number shimming piece
During more than the threshold value pre-set, judge that the number of shimming piece is wrong, and/or when the magnetic flux of the measurement and one set number
When difference between the calculating magnetic flux of shimming piece is less than the threshold value pre-set, judge that the number of shimming piece is correct.
In one embodiment, magnetic flux that can be based on the unit shimming piece magnetic flux that pre-sets and measurement, really
Determine the number of shimming piece.Herein, setting unit shimming piece is saturated caused magnetic flux during magnetization, i.e. unit shimming first
Piece magnetic flux；Then by the magnetic flux of measurement divided by the unit shimming piece magnetic flux, you can to obtain the specific number of shimming piece.
Based on above-mentioned labor, embodiment of the present invention also proposed a kind of shimming piece detecting system.
Fig. 3 is the detecting system structure chart of the shimming piece of the magnetic resonance imaging system of embodiment of the present invention.
As shown in figure 3, the system includes：
Multiple shimming pieces 3011,3012...301n shimming box 301 are accommodated, can be with cloth between each shimming piece
It is equipped with dielectric film.Shimming box 301 is typically made up of non-magnetic material.
Shimming piece detection means 302 is used to produce magnetic field.Shimming piece 3011,3012...301n in shimming box 301 is even
Magnetic field saturated magnetization produced by field piece detection means 302.Shimming piece detection means 302 is additionally operable to detect shimming in shimming box 301
Piece 3011, the 3012...301n magnetic flux caused by the magnetic field saturated magnetization.For example shimming piece detection means 302 can wrap
Include field-generating coil and flux sensing coil.
Magnetic flux phasor measurement unit 303 is used to measure the magnetic flux that shimming piece detection means 302 is detected.Such as magnetic flux
Measuring unit 303 specifically may be embodied as magneto-electric fluxmeter, electronic type fluxmeter or digital integration formula fluxmeter.
Computing unit 304, the magnetic flux for being measured based on magnetic flux phasor measurement unit 303 determine shimming piece in shimming box
Number.
For example it can be preserved in computing unit 304 corresponding to setting number (being assumed to be m) individual shimming piece saturated magnetization
Magnetic flux is calculated, and when the difference between the magnetic flux of measurement and the calculating magnetic flux is more than the threshold value that one pre-sets,
Judge that the number (n) of shimming piece is not met with setting number (m) in shimming box, and/or, when magnetic flux and the calculating magnetic of measurement
When difference between flux is less than the threshold value that one pre-sets, judge that shimming piece (n) is with setting number (m) to be consistent in shimming box
Close, i.e. n is equal to m.
For another example, magnetic flux that can be based on the unit shimming piece magnetic flux pre-set and the measurement, it is accurate really
Determine the number of shimming piece.Herein, setting unit shimming piece is saturated caused magnetic flux during magnetization, i.e. unit shimming first
Piece magnetic flux；Then by the magnetic flux of measurement divided by the unit shimming piece magnetic flux, you can to obtain the specific number of shimming piece.
In magnetic resonance practical application, generally multiple shimming pieces are stacked up, and is encapsulated into shimming box.
Fig. 4 is the detecting system structure chart according to the shimming piece of the magnetic resonance imaging system of embodiment of the present invention.
As shown in figure 4, shimming piece bracket 1 is supported by multiple shimming boxes made of non-magnetic material, specially shimming box A,
Shimming box B... shimming boxes M.
Each shimming box is made up of non-magnetic material.Multiple shimming pieces are accommodated in each shimming box.By shimming
Box is installed to before magnetic resonance system, can use the shimming piece detection means of embodiment of the present invention in each shimming box
Shimming piece number is examined.
Shimming piece detection means includes field-generating coil 3 and flux sensing coil 4.When needing to verify some shimming box
In shimming piece number when, field-generating coil 3 and flux sensing coil 4 just wind shimming box to be verified.
As shown in figure 4, shimming piece detection means is examining the shimming piece number in shimming box J.
Below for being described in detail exemplified by shimming box J checking.
As shown in figure 4, field-generating coil 3 and flux sensing coil 4 wind shimming box J.Field-generating coil 3 with it is straight
Stream power supply 5 connects.On dc source 5 after electricity, magnetostatic field can be produced in field-generating coil 3.Based on shimming piece in shimming box J
Magnetization characteristic (such as magnetic conductivity, magnetization curve, saturation magnetization, etc.), it may be determined that go out in saturated magnetization shimming box J
Magnetic field intensity needed for shimming piece, and the current parameters in magnetic field needed for the generation magnetic saturation shimming piece can be determined.Direct current
Power supply 5 provides electric current based on the current parameters of the determination to field-generating coil 3, so that produced by field-generating coil 3
Magnetostatic field saturated magnetization shimming box J in shimming piece.
Shimming piece in magnetization shimming box J is saturated after magnetization, and magnetic flux can be detected by flux sensing coil 4
Amount.When shimming piece is saturated magnetization, the shimming piece of quantitative number can produce the flux change proportional to the quantitative number.
Therefore, the magnetic flux detected using flux sensing coil 4 can verify the number validity of multiple shimming pieces.
Fluxmeter 6 is connected with flux sensing coil 4, for determining the magnetic flux detected by flux sensing coil 4.
Moreover, the magnetic flux determined is sent to computer 7 by fluxmeter 6.
The calculating magnetic flux for corresponding in shimming box J and number shimming piece saturated magnetization being set is preserved in computer 7, and is worked as
When difference between the magnetic flux of measurement and the calculating magnetic flux is more than the threshold value pre-set, shimming box in shimming box is judged
The number of shimming piece is not met with setting number in J, and/or, the difference between the magnetic flux of measurement and the calculating magnetic flux
During less than the threshold value pre-set, judge that the number of shimming piece and setting number are correct in shimming box J in shimming box.
, can be by shimming box J's when computer 7 judges that the number of shimming piece is with setting number not meet in shimming box J
Installation site sets to mistake and installed in list, and gives the user correct shimming piece installation data (i.e. setting number
Mesh), to prompt user to perform subsequent error correction processing.
Computer 7 is also based on the unit shimming piece magnetic flux pre-set and the magnetic flux of measurement, determines shimming
The number of shimming piece in box J.Here, setting unit shimming piece is saturated caused magnetic flux during magnetization first, i.e. unit is even
Field piece magnetic flux；Then by the magnetic flux of measurement divided by the unit shimming piece magnetic flux, you can to obtain the specific number of shimming piece
Mesh.
Similar said process, can enter according to predefined procedure to the shimming piece in other shimming boxes in shimming piece bracket 1
Row checking, and terminate rear line in checking and mistake installation list is presented.
It should be noted that step and module not all in above-mentioned each flow and each structure chart is all necessary, can
To ignore some steps or module according to the actual needs.The execution sequence of each step is not fixed, can be entered as needed
Row adjustment.The division of each module is intended merely to facilitate the division functionally that description uses, and when actually realizing, a module can
Realized with point by multiple modules, the function of multiple modules can also be realized by same module, and these modules can be located at same
In individual equipment, it can also be located in different equipment.
Hardware module in each embodiment mechanically or can be realized electronically.A for example, hardware module
Can be specific for completing including the permanent circuit specially designed or logical device (such as application specific processor, such as FPGA or ASIC)
Operation.Hardware module can also include PLD or circuit by software provisional configuration (as included general procedure
Device or other programmable processors) it is used to perform specific operation.Use mechanical system as specific, or special permanent of use
Property circuit, or hardware module is realized using the circuit (such as being configured by software) of provisional configuration, can according to cost and
It is temporal to consider to determine.
Present invention also offers a kind of machine readable storage medium, stores for making a machine perform side as described herein
The instruction of method.Specifically, system or device equipped with storage medium can be provided, store on the storage medium in realization
The software program code of the function of any embodiment in embodiment is stated, and makes the computer of the system or device (or CPU
Or MPU) read and perform the program code being stored in storage medium.Further, it is also possible to pass through the instruction based on program code
Make operating system of calculating hands- operation etc. to complete partly or completely practical operation.It will can also be read from storage medium
Program code write in memory set in expansion board in insertion computer or write what is be connected with computer
In the memory set in expanding element, the then instruction based on program code makes to be arranged on expansion board or expanding element
CPU etc. comes executable portion and whole practical operations, so as to realize the function of any embodiment in above-mentioned embodiment.
For provide program code storage medium embodiment include floppy disk, hard disk, magneto-optic disk, CD (such as CD-ROM,
CD-R, CD-RW, DVD-ROM, DVD-RAM, DVD-RW, DVD+RW), tape, Nonvolatile memory card and ROM.Selectively,
Can by communication network from server computer download program code.
In summary, in the shimming piece detection means of embodiment of the present invention, magnetic filed generation unit, for producing magnetic
；Magnetic flux amount detection unit, for detecting shimming piece magnetic flux caused by the magnetic field saturated magnetization；Computing unit,
For determining the number of the shimming piece based on the magnetic flux.As can be seen here, the shimming piece based on quantitative number can produce with
The proportional magnetic flux of the quantitative number, this hair invention embodiment magnetic flux detected when being magnetized by shimming piece
The automatic checking shimming piece number of amount, without manually checking checking, so as to significantly improve operating efficiency.
Moreover, in shimming piece in the case of packed, embodiment of the present invention can still verify shimming piece number automatically
Mesh, checking is checked without shimming box is opened manually, so as to also improve the scope of application.
Further, embodiment of the present invention, so as to avoid multiple shimming problem, can be reduced with accurate validation shimming piece quantity
Set-up time, and saved liquid helium.
The foregoing is only a preferred embodiment of the present invention, is not intended to limit the scope of the present invention.It is all
Within the spirit and principles in the present invention, any modification, equivalent substitution and improvements made etc., the protection of the present invention should be included in
Within the scope of.
Claims (8)
1. a kind of detection means of the shimming piece of magnetic resonance imaging system, including：
One magnetic filed generation unit, for producing a magnetic field；
One magnetic flux amount detection unit, for detecting shimming piece magnetic flux caused by the magnetic field saturated magnetization；
One computing unit, for determining the number of the shimming piece based on the magnetic flux.
2. the detection means of shimming piece according to claim 1, it is characterised in that the magnetic filed generation unit includes a magnetic
Field produces coil.
3. the detection means of shimming piece according to claim 1 or 2, it is characterised in that the magnetic flux amount detection unit bag
Include a flux sensing coil and a fluxmeter.
4. the detection means of shimming piece according to claim 3, it is characterised in that the flux sensing coil and described
Field-generating coil forms a self coupling coil.
5. the detection means of shimming piece according to claim 1, it is characterised in that
The computing unit, is used for：
Based on the unit magnetic flux and the magnetic flux pre-set, the number of the shimming piece is determined；And/or
Pre-set when the absolute value of the difference between the magnetic flux and a calculating magnetic flux of setting number shimming piece is more than
A threshold value when, judge that the number of the shimming piece is wrong, and/or when the magnetic flux with set number shimming piece a meter
When calculating the absolute value of the difference between magnetic flux less than the threshold value pre-set, judge that the number of the shimming piece is correct.
6. a kind of detection method of the shimming piece of magnetic resonance imaging system, including：
Produce a magnetic field；
Detect shimming piece magnetic flux caused by the magnetic field saturated magnetization；
The number of the shimming piece is determined based on the magnetic flux.
7. the detection method of shimming piece according to claim 6, it is characterised in that this method includes：
Based on the unit magnetic flux and the magnetic flux pre-set, the number of the shimming piece is determined；And/or
Pre-set when the absolute value of the difference between the magnetic flux and a calculating magnetic flux of setting number shimming piece is more than
A threshold value when, judge that the number of the shimming piece is wrong, and/or when the magnetic flux with set number shimming piece a calculating
When the absolute value of difference between magnetic flux is less than the threshold value pre-set, judge that the number of the shimming piece is correct.
8. a kind of magnetic resonance imaging system, include the detection means of the shimming piece as described in claim 1-5 is any.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410070563.8A CN104880683B (en) | 2014-02-28 | 2014-02-28 | A kind of detection means of the shimming piece of magnetic resonance imaging system, method and system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410070563.8A CN104880683B (en) | 2014-02-28 | 2014-02-28 | A kind of detection means of the shimming piece of magnetic resonance imaging system, method and system |
Publications (2)
| Publication Number | Publication Date |
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| CN1197525C (en) * | 2000-10-06 | 2005-04-20 | 株式会社新王磁材 | Apparatus for magnetic field regulation, magnetic field regulating method and recording medium |
| CN100516865C (en) * | 2003-05-21 | 2009-07-22 | 通用电气公司 | Method and system for evaluating core stack pressure |
| CN101688850A (en) * | 2007-07-09 | 2010-03-31 | 佳能株式会社 | Magnetic detection element and detection method |
| CN101688849A (en) * | 2007-07-09 | 2010-03-31 | 佳能株式会社 | Magnetic detection element and detecting method |
| CN103442635A (en) * | 2011-03-25 | 2013-12-11 | 株式会社日立医疗器械 | Method for adjusting static magnetic field homogeneity, static magnetic field generation device for magnetic resonance imaging, magnetic field adjustment system, and program |
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| CN1197525C (en) * | 2000-10-06 | 2005-04-20 | 株式会社新王磁材 | Apparatus for magnetic field regulation, magnetic field regulating method and recording medium |
| CN100516865C (en) * | 2003-05-21 | 2009-07-22 | 通用电气公司 | Method and system for evaluating core stack pressure |
| CN101688850A (en) * | 2007-07-09 | 2010-03-31 | 佳能株式会社 | Magnetic detection element and detection method |
| CN101688849A (en) * | 2007-07-09 | 2010-03-31 | 佳能株式会社 | Magnetic detection element and detecting method |
| CN103442635A (en) * | 2011-03-25 | 2013-12-11 | 株式会社日立医疗器械 | Method for adjusting static magnetic field homogeneity, static magnetic field generation device for magnetic resonance imaging, magnetic field adjustment system, and program |
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