CN104771170B - Towards the Pneumatic booster exciting bank and method of magnetic resonance elastography - Google Patents
Towards the Pneumatic booster exciting bank and method of magnetic resonance elastography Download PDFInfo
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- CN104771170B CN104771170B CN201510237602.3A CN201510237602A CN104771170B CN 104771170 B CN104771170 B CN 104771170B CN 201510237602 A CN201510237602 A CN 201510237602A CN 104771170 B CN104771170 B CN 104771170B
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- A61B5/05—Detecting, measuring or recording for diagnosis by means of electric currents or magnetic fields; Measuring using microwaves or radio waves
- A61B5/055—Detecting, measuring or recording for diagnosis by means of electric currents or magnetic fields; Measuring using microwaves or radio waves involving electronic [EMR] or nuclear [NMR] magnetic resonance, e.g. magnetic resonance imaging
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Abstract
The present invention discloses a kind of Pneumatic booster exciting bank and method towards magnetic resonance elastography, including vibration machine and bridge joint mechanism, vibration machine includes T-shape push rod, T-shape push rod disc edge is tightly connected by the closed gas storehouse of vibration end support film and vibration end, it is provided with the closed gas storehouse of vibration end on the downside of vibration end sealing film, T-shape push rod disc and is provided with relative balancing spring；Bridging mechanism includes minitype cylinder, air gauge and bridge joint head；Bridge and bridge end sealing film is provided with head, bridge joint head lower edge is connected by bridge end support film with disc edge on " work " type push rod, and " work " type push rod both sides are provided with extension spring.The present invention by improving catheter interior gas pressure intensity, make spread speed of the mechanical wave in conduit faster, energy loss it is less.Enhance to the excitation in inside of human body tissue, make elastogram quality higher.
Description
Technical field
The invention belongs to magnetic resonance elastography technical field, it is related to a kind of external drive skill of magnetic resonance elastography
Art, specifically a kind of Pneumatic booster exciting bank and method towards magnetic resonance elastography.
Background technology
Elasticity is the mechanical attribute of tissue, is a kind of important physical property.Modulus of elasticity between normal structure is not
Identical to the greatest extent, normal structure is compared with pathological tissue, and both elasticity is even more the presence of larger difference.The elastic size of tissue and change
Situation, directly reflects its structure composed, and closely bound up with its biological nature, physiology morbid state.
Traditional imaging method, such as ultrasound, CT and traditional magnetic resonance imaging, can not all provide the biomethanics category of tissue
Property, and magnetic resonance elastography can intuitively show as a kind of new noninvasive imaging method and quantify inside of human body tissue
Elasticity, and the elasticity of tissue is imaged, make it possible " image palpation ".
The general principle of magnetic resonance elastography is：Using mr imaging technique, produced by elastic wave excitation device
Elastic wave, organization internal is transmitted to by tissue surface, in the presence of elastic wave, and organization internal produces particle displacement, utilizes magnetic
The phase contrast techniques that resonate obtain phase difference, can detect micro-displacement, are detected according to the wave phase figure backstepping inverting of acquisition
The coefficient of elasticity distribution map of tissue, i.e. resonance elastic diagram.It can be seen that there is provided a kind of efficient exciting technique be resonance elastic into
The key of picture.
Traditional excitation system mainly uses pneumatic process, air-operated drive system it is general by vibration machine, conduction mechanism and
Adsorption head is constituted.Vibration machine is made up of signal generator, power amplifier and shake table.Conduction mechanism uses plastic flexible pipe
One section of air of sealing realizes conduction.Requirement in view of magnetic resonance elastography system to device magnetic compatibility, is clinically needed
Vibration machine is disposed away to the place of scan table, in case its electromagnetic field and conducting magnetic component are produced to magnetic resonance sequence and done
Disturb, therefore, the length of plastic flexible pipe at least needs 3-5 meters in conduction mechanism.
When the timing of mechanical wave energy one that vibration machine is exported, due to the compressibility of gas, form one it is similar
The structure of low pass filter so that the energy transfer efficiency of some mechanical ripple is decreased obviously.The mechanical wave-amplitude for reaching human body becomes
It is small, tissue can be penetrated, the energy for reaching imageable target point is then smaller, badly influences image quality.
Replace gas according to liquid medium, and replace electromagnetic vibration generator with hydraulic vibration generator, as
Energy source.Liquid medium is different from gas, and with Incoercibility, therefore the energy loss of conductive process is smaller, transmission efficiency
It is high.But, the quality of liquid is much larger than gas, and the gross energy of transmission with the need is also much larger than gas medium.In addition, fluid pressure type shakes
The driving frequency of dynamic generator is less than 40Hz, it is impossible to meet the frequency requirement of magnetic resonance elastography.
The A of application publication number CN 104000591 disclose a kind of magnetic resonance elastography active absorption type bridge joint excitation dress
Put, it is intended to solve existing the problem of magnetic resonance elastography Elastic Wave transformation efficiency is low.
Based on this, the technical scheme that provides of the present invention is on the basis of gas medium there is provided one kind towards resonance elastic
The Pneumatic booster exciting bank and method of imaging, significantly improve mechanical wave transmission efficiency.
The content of the invention
It is an object of the invention to provide a kind of Pneumatic booster exciting bank and method towards magnetic resonance elastography, purport
The transmission efficiency of mechanical wave in magnetic resonance elastography is improved.
The purpose of the present invention can be achieved through the following technical solutions：
It is described to shake towards the Pneumatic booster exciting bank of magnetic resonance elastography, including vibration machine and bridge joint mechanism
Dynamic generator includes being fixed with T-shape push rod on signal generator, power amplifier and the shake table being sequentially connected, shake table,
T-shape push rod disc edge is tightly connected by the closed gas storehouse of vibration end support film and vibration end：
It is provided with the downside of vibration end sealing film, described T-shape push rod disc and is provided with the closed gas storehouse of described vibration end
Relative balancing spring；
Described bridge joint mechanism includes minitype cylinder, air gauge and bridge joint head, and the closed gas storehouse of vibration end passes through plastic catheter
It is connected with bridge joint head, plastic catheter disconnects close to shake table side, forms two free ends, two free ends are respectively connected to four-way
Two relative interfaces of connector, two other interface of four connectors is connected to minitype cylinder and air gauge；
Bridge end sealing film is provided with described bridge joint head, bridge joint head lower edge passes through bridge end support film and " work "
Disc edge is connected on type push rod, and described " work " type push rod both sides are provided with extension spring.
Described balancing spring upper end on the downside of T-shape push rod disc with being fixed, and lower end is set on the supporting plate, supporting plate one end
It is fixed on shake table inwall；Described extension spring upper end is fixed with bridge joint head edge, and lower end is located under " work " type push rod on disc.
Described balancing spring and extension spring lower end position are adjustable, and adjusting method is：Bolt passes through fixing nut, and and spring
It is connected, swivel bolt just adjustable springs length.
Described vibration end sealing film, bridge end sealing film are elastic film, and its material is common for any one magnetic
The flexible organic polymer for compatibility of shaking, including silica gel thin film.
Described " work " shape push rod uses nylon nonmetallic materials；Extension spring uses latex flexible pipe.
Present invention also offers a kind of Pneumatic booster motivational techniques towards magnetic resonance elastography, Pneumatic booster excitation
The step of method includes following orders：
Open the valve of minitype cylinder, by minitype cylinder into sealing type pressure gas storehouse gas boosting, boost pressure reaches
During air gauge setting value, stop supercharging, close valve；
Adjustment spring, extension spring make T-shape push rod and " work " type push rod return to equilbrium position；
By " work " type push rod alignment human testing position；
Enabling signal generator and power amplifier.
Beneficial effects of the present invention：On the air-operated drive device basic of existing magnetic resonance elastography, the present invention is used
Pneumatic booster exciting bank, and closed, the elastic and dynamic balance that supercharging is brought is solved the problems, such as, by improving catheter interior gas
Body pressure, make spread speed of the mechanical wave in conduit faster, energy loss it is less.Enhance to swashing in inside of human body tissue
Encourage, make elastogram quality higher.
Brief description of the drawings
For the ease of it will be appreciated by those skilled in the art that the present invention is further illustrated below in conjunction with the accompanying drawings.
Fig. 1 is structural representation of the invention；
Fig. 2 is device simplified model；
Fig. 3 is device amplitude frequency curve.
Figure number explanation：1st, shake table；2nd, balancing spring；3rd, T-shape push rod；4th, vibration end sealing film；5th, vibrate
Hold support film；6th, sealing type pressure gas storehouse；7th, four connectors；8th, air gauge；9th, minitype cylinder；10th, valve；11st, bridge end
Sealing film；12nd, extension spring；13rd, " work " type push rod；14th, bridge end support film；15th, head is bridged；16th, plastic catheter.
Embodiment
As shown in Figure 1, the present invention mainly includes two big portions towards the Pneumatic booster exciting bank of magnetic resonance elastography
Point：Vibration machine and bridge joint mechanism.
Vibration machine includes signal generator, power amplifier and shake table 1, signal generator and power amplifier phase
Even, power amplifier is connected with shake table 1.Bridging mechanism includes minitype cylinder 9, air gauge 8 and bridge joint first 15, minitype cylinder 9
It is connected to air gauge 8 on two relative interfaces of four connectors 7.Shake table 1 and bridge joint first 15 pass through plastic catheter
16 are connected with two other interfaces of four connectors 7.
In order to ensure effective transmission of mechanical wave, the closed structure at plastic catheter two ends must be using elastic support side
Formula.Take after pressurized measure, improve the density of closed gas column in plastic catheter, also raised the internal pressure of gas column.Gas column
Endogenetic process has caused a deviation from equilbrium position in resilient support, the serious transmission for hindering mechanical wave.Therefore need to increase newly
Elastic construction, special balance gas column internal force.
In order to obtain closed gas column, in vibration end, addition vibration end sealing film 4, with closed effect, while also having
Elasticity, the transmission of without prejudice to mechanical wave.After supercharging, vibration end sealing film 4 is outwardly by gas column endogenetic process, deviates balance
Position, elapses downwards "T"-shaped push rod 3, causes it to deviate equilbrium position, has influence on the normal work of vibration machine.Therefore, increasing
Plus balancing spring 2, apply upward thrust, allow "T"-shaped push rod 3 to return to equilbrium position.Around "T"-shaped push rod 3, there is vibration end
Support film 5, "T"-shaped push rod 3-dimensional is held on median vertical line, it is to avoid its left and right skew under pressure is rocked.
In bridge end, closed and balance method is similar with vibration end.Bridge end sealing film 11 plays closed effect.Supercharging
After, bridge end sealing film 11 is outwardly, extruding " work " shape push rod 13.To balance this squeezing action, increase balance is drawn
Spring 12.Around " work " shape push rod 13, equally there is bridge end support film 14, keep the horizontal stable of push rod.With vibration end
Difference, all devices of bridge end should not all use metal material." work " shape pushes away 13 bars can be using nonmetallic materials such as nylon；And
Extension spring 12 can then use latex flexible pipe.
Close to the side of vibration end in plastic catheter 16, there are four connectors 7 to connect air gauge 8, minitype cylinder 9 and valve
Door 10.Inflated by minitype cylinder, the pressure of gas column, reaches setting value inside increase plastic catheter.
When being pressurized setting value difference, the internal force of closed gas column is also different, and the external force for balancing therewith is also different.It is just flat
Weigh for spring 2 and extension spring 12, to provide different equilibrant force, fix one end of spring, another end position is adjustable.One just
Prompt adjusting method is that bolt passes through fixing nut, and is connected with spring, swivel bolt just adjustable springs length there is provided not
Same equilibrant force.
Towards the Pneumatic booster motivational techniques of magnetic resonance elastography：
Before using this supercharging device, valve 10 is first opened, gas increases into sealing type pressure gas storehouse 6 by minitype cylinder 9
Pressure.
When being pressurized with minitype cylinder 9, notice whether the reading for observing air gauge 8 reaches setting value.When sealing type pressure gas storehouse 6
Needed for interior gas pressure intensity reaches during setting value, stop supercharging, and close valve 10,
Then adjustment spring 2 and extension spring 12 make T-shape push rod 3 and " work " type push rod 13 return to equilbrium position.
By the alignment human testing of " work " type push rod 13 position.Enabling signal generator and power amplifier, are occurred by signal
Device produces a Low Frequency Sine Signals, and shake table 1, the output predetermined amplitude of shake table 1 and frequency are inputed to after amplifying through power amplifier
The mechanical oscillation of rate, produce elastic wave.Then shake table 1 drives the synchronous vibration of T-shape push rod 3.It is same that T-shape push rod 3 vibrates
When, by the gas in the constantly compression of vibration end sealing film 4 and stretching sealing type pressure gas storehouse 6, elastic wave is in sealing type pressure gas
Efficient propagation in storehouse 6, and drive bridge end sealing film 11 to move reciprocatingly, and then make " work " type push rod 13 make machinery together to shake
It is dynamic.Air-operated drive method, by increasing the gas pressure intensity in conduction mechanism, make mechanical wave endotracheal spread speed faster,
Energy loss is less, significantly enhances communication effect of the vibration in inside of human body tissue, makes the better quality of elastogram figure.
It is pressurized exiting principle：
The present invention can be reduced to model as shown in Figure 2.Wherein, in the sealing type pressure gas storehouse 6 of the formation of plastic catheter 16
Sealing gas be considered as a gas spring, coefficient of elasticity isWherein p is the pressure of closed gas；S is plastics
The cross-sectional area of conduit 16；L is the total length of plastic catheter 16.Assuming that T-shape push rod 3 produces lasting exciting force F=Hsin
(ω t+ δ), wherein H is the maximum of the amplitude, i.e. exciting force of exciting force；ω is the angular frequency of exciting force；δ is the first of exciting force
Phase, they are all definite values.M is the quality of " work " shape push rod 13.Setting up the equation of motion of particle has：
The angular frequency of free vibrationIt is only relevant with system self character, including quality m and rigidity k.By matter
Point differential equation of motion is transformed into：
WhereinThe solution for obtaining it is：
X=Asin (ωnT+ α)+Bsin (ω t+ δ),
WhereinAbove formula shows：The characteristics of motion of undamped forced vibration is synthesized by two simple harmonic oscillations
's：Part I is the free vibration of intrinsic frequency, and Part II is the forced vibration of excitation force frequency.In actual vibration system
Middle damping is constantly present, and free vibration part can gradually decay.Therefore the feature of forced vibration need to only be focused on.
Under conditions of harmonic excitation, the forced vibration of system is simple harmonic oscillation, and its vibration frequency is equal to excited frequency, shaken
Width size B is unrelated with motion initial conditions, and relevant with the intrinsic frequency of vibrational system, and with amplitude H, the exciting force of exciting force
Frequencies omega it is relevant.B and ω relation is as shown in figure 3, the curve is referred to as amplitude frequency curve.In curve, when ω is more than ωn
When, B is the opposite in phase of negative value, now vibration phase and exciting force, 180 degree is differed, due to traditionally amplitude is taken on the occasion of institute
Using B in scheming as absolute value.In the device of the present invention, the intrinsic frequency of closed gas column is smaller, and excited frequency ω is always more solid than system
There is frequencies omeganWill big (ω>ωn), i.e., apparatus of the present invention it is actual only exist right side monotonic decreasing curve.By the bullet of gas spring
Property coefficient k brings into B and can obtainedH, s, l, m are definite value in the formula.To one setting driving frequency ω, when
When increasing the pressure p of closed gas column, it is known that B absolute value can increase, i.e. the amplitude of " work " type push rod can become big.Mechanical oscillation exist
The density of spread speed and gas in gas is directly proportional, and increases the pressure p of closed gas column and can improve gas in closed gas column
Density, so as to improve the spread speed of mechanical oscillation.So, by supercharging, mechanical wave can be made to be passed in closed gas column
Sowing time energy loss is less, and speed faster, significantly improves the image quality of elastogram figure.
Above content is only to structure example of the present invention and explanation, affiliated those skilled in the art couple
Described specific embodiment is made various modifications or supplement or substituted using similar mode, without departing from invention
Structure surmounts scope defined in the claims, all should belong to protection scope of the present invention.
Claims (6)
1. towards the Pneumatic booster exciting bank of magnetic resonance elastography, including vibration machine and bridge joint mechanism, the vibration
Generator, which includes being fixed with T-shape on the signal generator, power amplifier and the shake table (1) that are sequentially connected, shake table (1), to be pushed away
Bar (3), T-shape push rod (3) disc edge is tightly connected by vibration end support film (5) with the closed gas storehouse of vibration end, and it is special
Levy and be：
It is provided with the downside of vibration end sealing film (4), described T-shape push rod (3) disc and sets in the closed gas storehouse of described vibration end
There is relative balancing spring (2)；
Described bridge joint mechanism includes minitype cylinder (9), air gauge (8) and bridge joint head (15), and the closed gas storehouse of vibration end passes through modeling
Material conduit (16) is connected with bridge joint head (15), and plastic catheter (16) disconnects close to shake table side, forms two free ends, two
Free end is respectively connected to two relative interfaces of four connectors (7), and four connectors (7) two other interface is connected to
Minitype cylinder (9) and air gauge (8)；
Bridge end sealing film (11) is provided with described bridge joint head (15), bridge joint head (15) lower edge supports thin by bridge end
Film (14) is connected with disc edge on " work " type push rod (13), and described " work " type push rod (13) both sides are provided with extension spring (12).
2. according to claim 1 towards the Pneumatic booster exciting bank of magnetic resonance elastography, it is characterised in that described
Balancing spring (2) upper end on the downside of T-shape push rod (3) disc with being fixed, and lower end is set on the supporting plate；Described extension spring (12) upper end
Fixed with bridge joint head (15) edge, lower end is located under " work " type push rod (13) on disc.
3. according to claim 2 towards the Pneumatic booster exciting bank of magnetic resonance elastography, it is characterised in that described
Balancing spring (2) and extension spring (12) lower end position are adjustable, and described balancing spring (2) adjusting method is：Bolt passes through fixed spiral shell
Mother, and being connected with spring, swivel bolt just adjustable springs length.
4. according to claim 1 towards the Pneumatic booster exciting bank of magnetic resonance elastography, it is characterised in that described
Vibration end sealing film (4), bridge end sealing film (11) are elastic film, and its material is any one magnetic resonance compatible
Flexible organic polymer.
5. according to claim 1 towards the Pneumatic booster exciting bank of magnetic resonance elastography, it is characterised in that described
" work " type push rod (13) uses nylon nonmetallic materials；Extension spring (12) uses latex flexible pipe.
6. towards the Pneumatic booster motivational techniques of magnetic resonance elastography, it is characterised in that the Pneumatic booster motivational techniques include
The step of following orders：
Open the valve of minitype cylinder, by minitype cylinder into sealing type pressure gas storehouse gas boosting, boost pressure reaches air pressure
During table setting value, stop supercharging, close valve；
Adjustment spring, extension spring make T-shape push rod and " work " type push rod return to equilbrium position；
By " work " type push rod alignment human testing position；
Enabling signal generator and power amplifier.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
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| CN201510237602.3A CN104771170B (en) | 2015-05-11 | 2015-05-11 | Towards the Pneumatic booster exciting bank and method of magnetic resonance elastography |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510237602.3A CN104771170B (en) | 2015-05-11 | 2015-05-11 | Towards the Pneumatic booster exciting bank and method of magnetic resonance elastography |
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| CN104771170B true CN104771170B (en) | 2017-08-25 |
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Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN106980096B (en) * | 2017-04-12 | 2023-11-24 | 苏州大学 | Soft tissue simulator for magnetic resonance test and simulation test method |
Family Cites Families (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR100894307B1 (en) * | 2007-12-03 | 2009-04-24 | 연세대학교 산학협력단 | Driver device for magnetic resonance elastography |
| US8706192B2 (en) * | 2008-02-16 | 2014-04-22 | Geng Li | Magnetic resonance elastograph system with hydraulic driver |
| JP2010016082A (en) * | 2008-07-02 | 2010-01-21 | Hitachi Ltd | Vacuum insulating container and vacuum insulating device |
| CN202489951U (en) * | 2011-12-08 | 2012-10-17 | 中国科学院深圳先进技术研究院 | Elastography excitation device and system |
| CN202386685U (en) * | 2011-12-08 | 2012-08-22 | 中国科学院深圳先进技术研究院 | Magnetic-resonance excitation system |
| CN103349551B (en) * | 2013-07-08 | 2015-08-26 | 深圳先进技术研究院 | A kind of magnetic resonance elastography method and system |
| KR101451023B1 (en) * | 2013-07-10 | 2014-10-14 | 고려대학교 산학협력단 | Vibrator for magnetic resonance elastography |
| CN104000591A (en) * | 2014-06-11 | 2014-08-27 | 合肥工业大学 | Magnetic resonance elastography active adsorption type bridging exciter |
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