CN1371000A - Completely opened magnetic resonant imaging instrument - Google Patents
Completely opened magnetic resonant imaging instrument Download PDFInfo
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- CN1371000A CN1371000A CN 01136738 CN01136738A CN1371000A CN 1371000 A CN1371000 A CN 1371000A CN 01136738 CN01136738 CN 01136738 CN 01136738 A CN01136738 A CN 01136738A CN 1371000 A CN1371000 A CN 1371000A
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Abstract
The present invention provides a completely opened magnetic resonant imaging instrument with constant magnetic field strength. By means of one specifically designed permanent magnet to produce one sheet homogeneous magnetic field area around the magnet, one specifically set RF winding to excite the body tissue in the sheet area with nuclear magnetic resonance; one specifically designed gradient winding and one specially designed pulse sequence, nuclear spinning space encoding and magnetic resonance imaging informatino extracting in the sample area is completed. By further information processing process similar that in conventional nuclear magnetic resonant imaging instrument, nuclear resonant image of body in the sheet area may be obtained. The nuclear resonant image of other body part may be obtained by shifting sickbed and repeating the said process.
Description
Technical field
The present invention relates to a kind of magnetic resonance imager (hereinafter to be referred as MRI).
Background technology
The MRI of prior art, its magnet ring are around patient body, and therefore doctor and nurse can not, can not be used for interventional therapy near patient; Simultaneously, it is the spherical territory of diameter 30～50cm that the MRI of prior art requires the magnet sample area, and allows patient body to free in and out this sample area, so magnet is huge and heavy, can not make and popularize lightweight MRI.
The MRI of prior art above-mentioned two intrinsic big shortcomings derive from its formation method.According to this method, be examined patient's the inspection area that is subjected to, for example head, thoracic cavity, abdominal cavity or the like at first must all place one (unevenness generally not allow to surpass 10 highly uniformly
-5About) in the sample area of stationary magnetic field, sample area is generally the ball territory of diameter 30～50cm.Then, on the chip select direction, add artificial gradient fields, make the human body that originally all is in the uniform sample area of magnetic field height be subjected to inspection area, be in respectively under the different magnetic field control of field intensity this moment along its different tissues aspect of gradient fields direction.According to nuclear magnetic resonance principle, at this moment use the radio-frequency field of different frequency can excite corresponding variant tissue aspect, that is use and the radio-frequency field of corresponding your frequency of the Rameau that is checked of field intensity at the place, certain purpose aspect present position that need excite of appointment, this target aspect can be excited, this process is called by gradient fields carries out the imaging level selection, is called for short level selection.The aspect of being stimulated claims the purpose aspect.After the purpose aspect is stimulated, carry out sequence of operations by suitable pulse train again, can draw the magnetic resonance information of the aspect of being stimulated, and form magnetic resonance image (MRI) with these information at last gradient coil, radio frequency source and spectrometer.After this, change rf frequency again and repeat said process, another selected aspect will be excited,, can draw the magnetic resonance image (MRI) of this aspect by the step identical with said process.After all were examined magnetic resonance image (MRI) that tissue gives fixed purpose aspect and all draw, inspection work was just accused and is finished.
According to above-mentioned formation method, build the spherical sample district of diameter 30～50CM, and the spatial non-uniformity of its midfield must not become indispensable condition above about 10-5.For reaching this target, under the prior art condition, sample area can only design at the magnet center position, and magnet is huge and heavy inevitably.Sample area must form the general layout of magnet ring around patient at the magnet center position, and it is impossible that interventional therapy is become; The magnet of huge heaviness then makes MRI can not make universal lightweight.
Summary of the invention
Purpose of the present invention promptly is to overcome the shortcoming of above-mentioned prior art.For reaching this purpose, the magnet system that the present invention proposes a kind of MR imaging method and designs by this method.
A kind of full open model MR imaging method according to the present invention proposes may further comprise the steps: (1) builds a thin slice shape uniform magnetic field sample area with magnet outside himself; (2) by servo-control system a target aspect being checked tissue is overlapped with described sample area; (3) activate above-mentioned target aspect with radio-frequency coil emission radio-frequency field; (4) gradient fields that produces on two orthogonal directionss by gradient coil non-bed thickness direction in sample area is carried out space encoding to the nuclear spin in the target aspect; (5) described target aspect is carried out magnetic resonance imaging; (6) move sick bed by servo-control system, select another target aspect and make it to enter sample area; (7) repeating step (3) one steps (6) repeatedly obtain to wish the magnetic resonance image (MRI) of the target complete aspect that obtains.
The present invention also provides a kind of full open model magnetic resonance imager, comprise magnet system, sick bed, transmitter, RF power amplifier, gradient power amplifier, switch and before put, display, computing machine, sequential control, receiver, it is characterized in that: also comprise a servo-control system, it is used for moving described sick bed, makes to be examined the organizational goal aspect and overlap with the magnet sample area.
According to a preferred embodiment of the present invention, described sick bed is made by non-conductive, nonferromagnetic material, is placed in the sample area below, patient couch top is parallel with thin slice shape sample area, and being lower than sample area 15-25cm, there is the liftable bearing at the bed surface rear portion, can make its rise by described servo-control system.
According to a further advantageous embodiment of the invention, described magnet system comprises yoke, the magnetic buttress, first gradient coil, second gradient coil, radio-frequency coil, it is characterized in that: described magnetic buttress comprises left side magnetic buttress and right side Ci Duo, the two left and right symmetrically is placed on the yoke, left side magnetic buttress and right side magnetic buttress are towards there being an angle between the surface of sick bed, between left side magnetic buttress and right side magnetic buttress, a shape is housed and adjusts iron, magnetic buttress and right side magnetic buttress were on the surface of sick bed on the left of first gradient coil and second gradient coil were separately fixed at, and the fixing shape on the scene of described radio-frequency coil is adjusted the place of close sick bed between iron and the sample area.
Further, left side magnetic buttress and right side magnetic buttress are preferably 0＜θ＜π towards the angle between the surface of sick bed in the full open model magnetic resonance imager of the present invention, described magnetic buttress is stacked by multiple permanent magnetic material layering, the formation wedge shape constitutes, one of wedge shape side is attached on the yoke, another side is towards sample area, the magnetic material direction of magnetization takes to start from wedge shape one surface, eventually to another surperficial direction of wedge shape, the permanent magnetic material of different layers is selected from permanent-magnet ferrite, or alnico alloy, or samarium-cobalt alloy, or sintered NdFeB.
Further, left side magnetic buttress and right side magnetic buttress are preferably 0 towards the angle between the surface of sick bed in the full open model magnetic resonance imager of the present invention, and described magnetic buttress is made of single a kind of permanent magnetic material, and left side magnetic buttress, right side magnetic buttress are strip.
Further, left side magnetic buttress and right side magnetic buttress are preferably π towards the angle between the surface of sick bed in the full open model magnetic resonance imager of the present invention, and described magnetic buttress is made of single a kind of permanent magnetic material, and left side magnetic buttress, right side magnetic buttress are strip.
And, in the full open model magnetic resonance imager of the present invention, it is strip that described shape adjusted iron, its transversal section can be taken as a kind of in square, rectangle, trapezoidal, semicircle or the circle, field shape is adjusted iron is fixed on left side magnetic buttress and right side magnetic buttress with adhering method or mechanical connection method confluce, when passing on meeting, then be fixed on the yoke of middle in the two magnetic buttress when between the two magnetic buttress distance being arranged.
In the full open model magnetic resonance imager of the present invention, described first gradient coil and second gradient coil are separately fixed at the left side magnetic buttress and the right side magnetic of magnet and pile up neatly on the surface of sick bed, on two orthogonal directionss of the non-bed thickness of sample area, produce the linear gradient field, the two shape, the number of turn are identical, and each partly can overlappingly place first gradient coil, second gradient coil on magnetic buttress surface.
In the full open model magnetic resonance imager of the present invention, described radio-frequency coil is laid the place that shape on the scene is adjusted close sick bed between iron and the sample area, and it is cemented in two magnetic buttress on the surface of sick bed by nonconducting nonferromagnetic material support.
Above-mentioned technology provided by the present invention is because sample area is positioned at a side of magnet, so doctor and nurse can close on patient, therefore MRI of the present invention can be used for interventional therapy; Form a sheet sample district and needn't form roomy spherical sample district in the magnet outside owing to the present invention only requires magnet again,, can make popular light MRI so magnet can be done both gently and little.
The present invention has the following advantages:
1, use a kind of level selection process of having cancelled, the target aspect that directly will be checked tissue is placed into non-sphere but removes the formation method of direct imaging in the form of sheets the sample area;
2, MRI of the present invention system has added Positioning Servo System in constituting.It is used to drag sick bed, and the various objectives aspect that will be examined tissue one by one moves to the magnetic field sample area and overlaps.
3, use a kind of magnet system that meets above-mentioned formation method requirement, it comprises magnet, gradient coil and radio-frequency coil, is characterized in: (1) one can produce the magnet in the magnetic field that comprises a thin slice shape uniform magnetic field sample area in the magnet outer space; (2) use places magnet face on the surface of sick bed one side, can produce two cover gradient coils of gradient fields on two orthogonal directionss of the non-bed thickness direction of sample area; (3) use between thin slice shape sample area and magnet locational radio-frequency coil near sick bed.
Followingly content of the present invention is explained in detail with reference to Fig. 1～Fig. 7.
Description of drawings Fig. 1, the system that shows MRI of the present invention constitute block diagram 2, show the pie graph 3 of magnet system of the present invention, show 0＜θ＜magnet pie graph 4 during π, the magnet pie graph 5 when showing θ=π, show θ=0 o'clock magnet pie graph 6, show and use specific embodiment Fig. 7, the many echoes spin echo pulse code sequence that the present invention carries out the head imaging
Embodiment
As shown in Figure 1, MRI of the present invention comprise transmitter, RF power amplifier, gradient power amplifier, switch and before put, display, computing machine, servo-control system, sequential control, receiver, magnet system and sick bed etc.These parts are connected by USB (universal serial bus).Advantages such as USB (universal serial bus) has easy for installation, supports plug and play, and transmission speed is fast.Total system adopts the personal computer (PC) of Pentium III processor (PIII) totally to control by one.Solid line among the figure and arrow have been represented the signal transmission situation of each module.MRI of the present invention compares with the MRI of prior art, and magnet system partly is special, hereinafter will describe in detail.Servocontrol also is distinctive partly, and it is used for the position with respect to magnet system of mobile sick bed on request, and the target aspect is overlapped with the magnet sample area.Sick bed is made by non-conductive, non-ferromagnetic material, is placed in the sample area below, and bed surface is parallel with thin slice shape sample area, but is lower than sample area 15～25cm.The liftable bearing is arranged at the bed surface bottom, makes its rise by servo-control system during work, and can be parked in desired location on request.
Fig. 2 shows the formation situation of magnet system of the present invention.As shown in the figure, as the irony flat board 21 of yoke, its left and right sides is furnished with left side magnetic buttress 22 and right side magnetic buttress 23 symmetrically, and left side magnetic buttress and right side magnetic buttress have an angle theta towards between the surface of sick bed.Magnetic flux is sent by right side magnetic buttress 23, crosses the space between the two magnetic buttress, penetrates left side magnetic buttress 22, by returning right side Ci Duo in the irony flat board 21, forms closed magnetic loop again.The magnetic buttress can be made of single a kind of permanent magnetic material, also can use more than one permanent magnetic material.In best enforcement of the present invention, when the magnetic buttress was designed to be made of more than one permanent magnetic materials, various permanent magnetic materials should stack by mode layering shown in Figure 3, form wedge shape, and one of wedge shape two sides are attached on the yoke, and another side is towards sample area.The direction of magnetization of magnetic material should take to start from wedge shape one surface generally, eventually to another surperficial direction of wedge shape.Magnetic is piled up neatly used permanent magnetic material and can be selected from permanent-magnet ferrite, alnico alloy, samarium-cobalt alloy, sintered NdFeB or the like.Being also shown in two magnetic buttress from Fig. 3 is 0＜θ＜π towards the variation range of angle theta between the surface of sick bed.Middle part between two magnetic buttress has a shape to adjust iron 24, and it attracts to cross the magnetic flux in the space between the two magnetic buttress, makes certain magnetic flux partly in the space between the two magnetic buttress move towards straight, is evenly distributed, and forms sample area 20 as shown in the figure.It is strip that shape is adjusted iron, and its transversal section can be taken as a kind of in square, rectangle, trapezoidal, semicircle or the circle, adjusts iron and piles up neatly on the surface with the magnetic that glueds joint or the mechanical connection method is fixed on the confluce of two magnetic buttress.When passing on meeting, then be fixed on the yoke of two Ci Duo middles when between the two magnetic buttress distance being arranged.Gradient coil comprises first gradient coil and second gradient coil, and directions X in sample area 20 and Y direction produce gradient magnetic respectively.First gradient coil 25 and second gradient coil 26 each by identical two partly the forming of structure, with splicing or mechanical connection manner be arranged in symmetrically that two magnetic pile up neatly on the sick bed surface.First, second gradient coil design is a tabular, two groups of gradient coils overlapping laying on magnetic buttress surface.Radio-frequency coil 27 among the figure is laid the place that shape on the scene is adjusted close sick bed between iron and the sample area, and it is cemented in two magnetic buttress on the surface of sick bed by nonconducting nonferromagnetic material support.
Situation when Fig. 4 shows angle theta=π, the magnetic buttress is made of single a kind of permanent magnetic material here, and left side magnetic buttress, right side magnetic buttress are strip, and iron is adjusted in the middle of two magnetic buttress in magnetic field, is fixed on the surface of yoke.Fig. 5 shows the situation of θ=0 o'clock, and the magnetic buttress is made of single a kind of permanent magnetic material here, and left side magnetic buttress, right side magnetic buttress are strip, and iron is adjusted in the middle of two magnetic buttress in magnetic field, is fixed on the surface of yoke.
Fig. 6 has provided an embodiment of magnet and coil when carrying out the head imaging.
According to the present invention, system will be subjected to the imaging for the treatment of of inspection area to organize aspect (this aspect of each layer is called a purpose aspect) to overlap with the laminar sample area that the method for mobile sick bed is produced itself and magnet one by one when patient head is carried out magnetic resonance imaging.When a purpose aspect with after sample area overlaps, promptly use the radio-frequency coil emission radio-frequency field between sample area and magnet that the purpose aspect is activated, rf frequency should be consistent with your frequency of Rameau of sample under being in the sample area field intensity.Use with the similar method of prior art then and finish information extraction and formation aspect magnetic resonance image (MRI), for example can use the many echoes spin echo coded sequence that usually uses among the MRI of prior art to remove to operate gradient coil, radio frequency source and spectrometer, obtain the magnetic resonance information of purpose aspect and finish the aspect magnetic resonance image (MRI), after the imaging process of a purpose aspect is finished, make follow-up purpose aspect finish said process one by one by mobile sick bed again, thereby finish whole imaging process.
In the present embodiment, the left side of magnet system and right side magnetic are piled up neatly mutual intersection, and angle theta is 120 °, and it is strip that a shape is adjusted iron, and its transversal section is a rectangle, places two Ci Duo confluces, sample region size: 0.2 * 0.2 * 0.005m
3, sample area field intensity: 0.15T, sample area field unevenness :≤10
-4, centre frequency: 6.62MHz, bandwidth: 100KHz, gradient fields sensitivity: 2mT/m.The magnetic buttress uses two kinds of permanent magnetic materials: permanent-magnet ferrite, sintered NdFeB.Fig. 7 shows and can be used for many echoes spin echo coded sequence of the present invention.Because formation method of the present invention has been removed the level selection process from, so removed control in the imaging coded sequence to Z direction gradient field, in fact the gradient coil and the corresponding gradient amplifier of Z direction have also been removed among the present invention, but in Fig. 7, still drawn the delegation of Gz, to show the natural gradient field that may exist in the sheet sample district for normal value.
Claims (12)
1, a kind of full open model MR imaging method may further comprise the steps:
(1) outside himself, builds a thin slice shape uniform magnetic field sample area with magnet;
(2) by servo-control system a target aspect being checked tissue is overlapped with described sample area;
(3) activate above-mentioned target aspect with radio-frequency coil emission radio-frequency field;
(4) gradient fields that produces on two orthogonal directionss by gradient coil non-bed thickness direction in sample area
Space encoding is carried out in nuclear spin in the target aspect;
(5) described target aspect is carried out magnetic resonance imaging;
(6) move sick bed by servo-control system, select another target aspect and make it to enter sample area;
(7) repeating step (3) one steps (6) repeatedly, the magnetic that obtains to wish the target complete aspect that obtains altogether
Image shakes.
2, a kind of full open model magnetic resonance imager according to the described MR imaging method design of claim 1, comprise magnet system, sick bed, transmitter, RF power amplifier, gradient power amplifier, switch and before put, display, computing machine, sequential control, receiver, it is characterized in that: also comprise a servo-control system, it is used for moving described sick bed, makes to be examined the organizational goal aspect and overlap with the magnet sample area.
3, full open model magnetic resonance imager as claimed in claim 2, it is characterized in that: described sick bed is made by non-conductive, nonferromagnetic material, be placed in the sample area below, patient couch top is parallel with thin slice shape sample area, and be lower than sample area 15-25cm, there is the liftable bearing at the bed surface rear portion, can make its rise by described servo-control system.
4, as claim 2 or 3 described full open model magnetic resonance imagers, it is characterized in that: described magnet system comprises yoke (21), magnetic buttress (22,23), first gradient coil (25), second gradient coil (26), radio-frequency coil (27), it is characterized in that: described magnetic buttress comprises left side magnetic buttress (22) and right side Ci Duo (23), the two left and right symmetrically is placed on the yoke, left side magnetic buttress and right side magnetic buttress are towards there being an angle (θ) between the surface of sick bed, between left side magnetic buttress and right side magnetic buttress, a shape is housed and adjusts iron (24), magnetic buttress and right side magnetic buttress were on the surface of sick bed on the left of first gradient coil (25) and second gradient coil (26) were separately fixed at, and the fixing shape on the scene of described radio-frequency coil (27) is adjusted the place of close sick bed between iron and the sample area.
5, full open model magnetic resonance imager as claimed in claim 4, it is characterized in that: described angle (θ) is 0＜θ＜π, and described magnetic buttress is stacked by multiple permanent magnetic material layering, forms wedge shape and constitutes, one of wedge shape side is attached on the yoke, another side is towards sample area, and the magnetic material direction of magnetization takes to start from wedge shape one surface, eventually to another surperficial direction of wedge shape, the permanent magnetic material of different layers is selected from and is permanent-magnet ferrite, or alnico alloy, or samarium-cobalt alloy, or sintered NdFeB.
6, full open model magnetic resonance imager as claimed in claim 4 is characterized in that: described angle (θ) is 0, and described magnetic buttress is made of single a kind of permanent magnetic material, and left side magnetic buttress, right side magnetic buttress are strip.
7, full open model magnetic resonance imager as claimed in claim 4 is characterized in that: described angle (θ) is π, and described magnetic buttress is made of single a kind of permanent magnetic material, and left side magnetic buttress, right side magnetic buttress are strip.
8, full open model magnetic resonance imager as claimed in claim 4 is characterized in that: it is strip that described shape is adjusted iron, and its transversal section can be taken as a kind of in square, rectangle, trapezoidal, semicircle or the circle.
9, full open model magnetic resonance imager as claimed in claim 4 is characterized in that: left side magnetic buttress and right side magnetic are piled up neatly mutual intersection, and a shape is adjusted ferropexy in left side magnetic buttress and Ci Duo confluce, right side.
10, as right 4 described full open model magnetic resonance imagers, it is characterized in that: keep certain distance and the meeting of passing between left side magnetic buttress and right side magnetic buttress, a shape is adjusted ferropexy on the yoke in the middle of the two magnetic buttress.
11, full open model magnetic resonance imager as claimed in claim 4, it is characterized in that: described first gradient coil and second gradient coil are separately fixed at the left side magnetic buttress and the right side magnetic of magnet and pile up neatly on the surface of sick bed, on two orthogonal directionss of the non-bed thickness of sample area, produce the linear gradient field, the two shape, the number of turn are identical, and each partly can overlappingly place first gradient coil, second gradient coil on magnetic buttress surface.
12, full open model magnetic resonance imager as claimed in claim 4, it is characterized in that: described radio-frequency coil is laid the place that shape on the scene is adjusted close sick bed between iron and the sample area, and it is cemented in two magnetic buttress on the surface of sick bed by nonconducting nonferromagnetic material support.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 01136738 CN1183873C (en) | 2001-07-25 | 2001-10-23 | Completely opened magnetic resonant imaging instrument |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN01120585.7 | 2001-07-25 | ||
| CN01120585 | 2001-07-25 | ||
| CN 01136738 CN1183873C (en) | 2001-07-25 | 2001-10-23 | Completely opened magnetic resonant imaging instrument |
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| CN1371000A true CN1371000A (en) | 2002-09-25 |
| CN1183873C CN1183873C (en) | 2005-01-12 |
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| CN 01136738 Expired - Fee Related CN1183873C (en) | 2001-07-25 | 2001-10-23 | Completely opened magnetic resonant imaging instrument |
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Cited By (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2006131060A1 (en) * | 2005-06-10 | 2006-12-14 | Beijing Taijie Yanyuan Medical Engineering Technical Co., Ltd. | Permanent magnet, magnetic device for use in mri including the same and manufanufacturing processes thereof |
| CN101266289B (en) * | 2008-04-25 | 2010-06-09 | 浙江大学 | Open type MRI system transverse gradient coil distortion space design method |
| CN1624465B (en) * | 2003-12-04 | 2010-06-16 | 株式会社东芝 | Magnetic resonance imaging apparatus and image generation method therein |
| CN102360689A (en) * | 2011-06-02 | 2012-02-22 | 中国科学院电工研究所 | Open type conduction cooling nuclear magnetic resonance superconducting magnet system |
| CN101598775B (en) * | 2009-06-19 | 2013-01-02 | 沈阳工业大学 | Medical magnetic resonance imager monohedral magnet device |
| CN104459583A (en) * | 2013-09-16 | 2015-03-25 | 西门子(深圳)磁共振有限公司 | Positioning method, device and system of local coil of magnetic resonance device |
| CN105632680A (en) * | 2016-03-28 | 2016-06-01 | 中国船舶重工集团公司第七一〇研究所 | Implementation method of combined magnetic field coil |
| CN111968822A (en) * | 2020-07-07 | 2020-11-20 | 无锡鸣石峻致医疗科技有限公司 | Permanent magnet suitable for portable nuclear magnetic resonance device |
| US20210003649A1 (en) * | 2013-12-19 | 2021-01-07 | Dentsply Sirona Inc. | Unilateral magnetic resonance scanning device for medical diagnostics |
| WO2021109348A1 (en) * | 2019-12-05 | 2021-06-10 | 无锡鸣石峻致医疗科技有限公司 | Portable nuclear magnetic resonance organ elasticity non-invasive quantitative measurement method |
| WO2021109347A1 (en) * | 2019-12-05 | 2021-06-10 | 无锡鸣石峻致医疗科技有限公司 | Portable nuclear magnetic resonance non-invasive quantitative testing system for elasticity of organ |
-
2001
- 2001-10-23 CN CN 01136738 patent/CN1183873C/en not_active Expired - Fee Related
Cited By (14)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1624465B (en) * | 2003-12-04 | 2010-06-16 | 株式会社东芝 | Magnetic resonance imaging apparatus and image generation method therein |
| WO2006131060A1 (en) * | 2005-06-10 | 2006-12-14 | Beijing Taijie Yanyuan Medical Engineering Technical Co., Ltd. | Permanent magnet, magnetic device for use in mri including the same and manufanufacturing processes thereof |
| CN101266289B (en) * | 2008-04-25 | 2010-06-09 | 浙江大学 | Open type MRI system transverse gradient coil distortion space design method |
| CN101598775B (en) * | 2009-06-19 | 2013-01-02 | 沈阳工业大学 | Medical magnetic resonance imager monohedral magnet device |
| CN102360689A (en) * | 2011-06-02 | 2012-02-22 | 中国科学院电工研究所 | Open type conduction cooling nuclear magnetic resonance superconducting magnet system |
| CN104459583A (en) * | 2013-09-16 | 2015-03-25 | 西门子(深圳)磁共振有限公司 | Positioning method, device and system of local coil of magnetic resonance device |
| CN104459583B (en) * | 2013-09-16 | 2017-11-17 | 西门子(深圳)磁共振有限公司 | A kind of localization method of the local coil of magnetic resonance device, device and system |
| US20210003649A1 (en) * | 2013-12-19 | 2021-01-07 | Dentsply Sirona Inc. | Unilateral magnetic resonance scanning device for medical diagnostics |
| CN105632680A (en) * | 2016-03-28 | 2016-06-01 | 中国船舶重工集团公司第七一〇研究所 | Implementation method of combined magnetic field coil |
| CN105632680B (en) * | 2016-03-28 | 2017-11-21 | 中国船舶重工集团公司第七一〇研究所 | A kind of implementation method of magnetic coil system |
| WO2021109348A1 (en) * | 2019-12-05 | 2021-06-10 | 无锡鸣石峻致医疗科技有限公司 | Portable nuclear magnetic resonance organ elasticity non-invasive quantitative measurement method |
| WO2021109347A1 (en) * | 2019-12-05 | 2021-06-10 | 无锡鸣石峻致医疗科技有限公司 | Portable nuclear magnetic resonance non-invasive quantitative testing system for elasticity of organ |
| CN111968822A (en) * | 2020-07-07 | 2020-11-20 | 无锡鸣石峻致医疗科技有限公司 | Permanent magnet suitable for portable nuclear magnetic resonance device |
| CN111968822B (en) * | 2020-07-07 | 2022-06-10 | 无锡鸣石峻致医疗科技有限公司 | Permanent magnet suitable for portable nuclear magnetic resonance device |
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| CN1183873C (en) | 2005-01-12 |
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