Magnetic resonance imaging system capable of being used for examination in upright load-bearing state

Abstract

The utility model relates to a magnetic resonance imaging system capable of being used for examination in a vertical load state, which is provided with an MRI magnet and / or an MRI main body, the MRI magnet and / or the MRI main body are / is vertically arranged, a vertical detection space is arranged in the MRI main body, the magnetic field of the detection space is a vertical magnetic field, the magnet of an MRI facility is made of magnesium diboride superconducting material, and the magnetic field of the MRI facility is made of magnesium diboride superconducting material. Solid nitrogen is used as a cooling medium, the phase change latent heat of the solid nitrogen is used for stabilizing the temperature under the condition of 35.6 K so as to facilitate vertical placement of the superconducting magnet, and the MRI main body is vertically and movably connected with the base through a lifting mechanism. The magnetic resonance imaging device is suitable for magnetic resonance imaging requirements in a vertical state.

Description

Technical Field

[0001] The utility model relates to a magnetic resonance imaging system which can be used for checking in an upright weight-bearing state, and belongs to the technical field of medical treatment. Background Art

[0002] Magnetic resonance imaging (MRI) can obtain a large amount of physiological and pathological information in the human body non-invasively, and has become an important diagnostic device that is indispensable for clinical work. The medical MRI equipment currently operating in hospitals requires patients to lie flat during the examination. Due to the structure and force of the human body, the flat state may conceal the diagnosis of some diseases and cause misdiagnosis. For example, patients with lumbar disc herniation, which has a high incidence rate, will have a reduced or even normal degree of lumbar disc herniation or bulging in a flat state, and the knee joints will also perform very differently when standing and under stress and lying flat without stress. In particular, patients with scoliosis, which is common in adolescents, will have a smaller scoliosis angle when the spine is not weight-bearing or stressed in a flat state, so patients can only receive X-ray full spine plain film photography. Since full spine photography cannot protect key parts such as the thyroid gland and reproductive system during the examination, it brings inaccuracies in detection to adolescents and other patients, and cannot meet clinical needs well.

[0003] The superconducting magnet of the existing MRI system is the development direction of the weight-bearing magnetic resonance system. The current conventional whole-body superconducting magnetic resonance magnet cannot be rotated 90 degrees from the horizontal direction to the vertical direction. The main reasons are: (1) The height of the magnet is too large, and it is difficult for the patient to enter the magnet scanning hole. (2) When the magnet rotates, the liquid helium level in the dewar will change, and some coils may lose liquid helium cooling, causing the magnet to quench, causing an accident. (3) The heat capacity of liquid helium is very low, and vibration will accelerate the vaporization of liquid helium. Therefore, the commonly used superconducting magnet cooled by liquid helium cannot be moved. When examining different parts of the spine, the patient can only move up and down so that the examination part is located in the center of the magnetic field. The movement of the patient during the examination does not meet clinical requirements and is difficult to achieve. The current advanced liquid helium-free magnetic resonance imaging system also has the requirement to keep the magnet stable. (4) Both liquid helium magnets and non-liquid helium magnets cannot be separated from the refrigerator, so the movement of the magnet requires the movement of the refrigerator at the same time, and the overall weight is large and inconvenient to move. Utility Model Content

[0004] In order to overcome the above-mentioned defects of the prior art, the utility model provides a magnetic resonance imaging system that can be used for examination in an upright weight-bearing state, so as to meet the demand for magnetic resonance imaging in an upright state.

[0005] The technical solution of the utility model is: a magnetic resonance imaging system that can be used for inspection in an upright weight-bearing state, provided with an MRI magnet (main magnet) and / or an MRI body (MRI equipment body), characterized in that the MRI magnet and / or the MRI body (the component / device provided with the MRI magnet) is vertically arranged, and an upright detection space (a space for patients to stand during inspection) is provided in the MRI body.

[0006] Furthermore, the magnetic field in the detection space is a vertical magnetic field.

[0007] Preferably, the magnet of the MRI facility uses magnesium diboride superconducting material.

[0008] Preferably, solid nitrogen is used as the cooling medium, and the latent heat of phase change of solid nitrogen at 35.6K is utilized to stabilize the temperature, so as to facilitate the vertical placement of the superconducting magnet.

[0009] Preferably, the overall shape of the MRI magnet and / or the MRI body is an upright ring (the axis of the ring is a vertical straight line).

[0010] Preferably, a lifting mechanism is provided, and the MRI body is vertically movably connected to the base via the lifting mechanism (connected in a movable connection manner that allows vertical movement relative to the base), and can move up and down.

[0011] Preferably, a temperature sensor is provided inside the MRI magnet for collecting / obtaining the temperature of the solid nitrogen inside the MRI magnet. The temperature of the solid nitrogen inside the MRI magnet can be obtained through the temperature sensor.

[0012] Preferably, the MRI magnet is connected to a detachable (capable of being detached) refrigerator, which is allowed / capable of being disconnected from the main magnet after cooling the solid nitrogen to a temperature below 35.6K, depending on actual operational needs.

[0013] Preferably, the MRI magnet is connected to a detachable refrigerator, and when the temperature of the solid nitrogen is close to or higher than 35.6K, the refrigerator is connected to the MRI magnet and starts cooling.

[0014] The MRI magnet is provided with a cooling medium interface (inlet and outlet interface) for connecting to a refrigerator. The refrigerator matched with the MRI magnet is a detachable refrigerator. The cooling medium interface (inlet and outlet interface) of the detachable refrigerator and the cooling medium interface of the MRI magnet adopt a matching quick-connect structure (a connection structure that can be quickly connected and quickly disassembled, for example, a docking / matching structure with a matching tongue and groove and a sealing ring).

[0015] The beneficial effects of the utility model are: changing the horizontal placement of magnets in existing MRI equipment, allowing patients to stand in the detection space of the magnet during the detection process, the magnetic field (main magnetic field) in the detection space is a vertical magnetic field, suitable for the detection of standing patients, the patient can easily enter the magnet, stand in the middle of the magnet and remain motionless, the magnet can be separated from the refrigerator, the magnet can be moved up and down, and the pathological changes of various parts of the patient's body under weight can be checked. The cooling medium is solid nitrogen, instead of expensive and scarce liquid helium. Save electricity. The refrigerator is only started when it is used, and the refrigerator stops after the liquid nitrogen in the dewar is converted into solid nitrogen and no longer consumes electricity. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic diagram of a use state of the utility model;

[0017] Figure 2 It is a schematic diagram of another use state of the utility model. DETAILED DESCRIPTION

[0018] See also Figure 1 The utility model is a magnetic resonance imaging system, in which the main magnet is placed vertically and the patient aperture is perpendicular to the horizontal plane. The main magnet is placed vertically and equipped with a lifting device, and the main magnet can be raised and lowered as needed. When not working, it is in the lowest position, and the patient can enter the magnet through the steps and stand in the center of the magnet. There is a device inside the magnet to assist the patient to stand, and then the magnet can be raised to the height of the inspection part. For example, when inspecting the knee joint, the magnet rises to the height of the knee joint so that the knee joint is located in the center of the magnet.

[0019] The MRI body is the main part / basic part of the MRI device, and the MRI magnet, coil and other facilities are arranged in its shell. The detection space is located in the middle of the MRI body.

[0020] The magnet is a superconducting magnet, and the superconducting wire is magnesium diboride. Compared with the niobium-titanium alloy used as the material for conventional magnetic resonance superconducting wires, the superconducting critical temperature of magnesium diboride is higher (39K), and the price of magnesium diboride is cheap. At the same time, the superconducting critical temperature of magnesium diboride is high, so it is not necessary to use expensive liquid helium as a cooling medium, but to use cheap solid nitrogen as a cooling medium. Solid nitrogen has a large latent heat of phase change at a temperature of 35.6K, and solid nitrogen can be used as a cold storage material to maintain the low-temperature stability of magnesium diboride superconductivity for a long time.

[0021] The main magnetic field coil is installed in the dewar, and liquid nitrogen or solid nitrogen can be contained between the coil and the inner wall of the dewar. The dewar is connected to the refrigerator through a pipeline. The refrigerator can cool the liquid nitrogen in the dewar into solid nitrogen and continue to refrigerate the solid nitrogen to a temperature below 35.6K.

[0022] A gradient coil and a radio frequency coil are installed in the room temperature hole of the barrel-shaped magnet. The gradient coil is connected to a gradient amplifier, and the radio frequency coil is connected to a radio frequency amplifier. The gradient amplifier and the radio frequency amplifier work in coordination under the control of the spectrometer.

[0023] Other subsystems and other facilities / structures of the MRI may be provided according to the existing technology.

[0024] Before the magnetic resonance system works, the refrigerator needs to be started to reduce the temperature inside the dewar to below 35.6K, and the liquid nitrogen is cooled to convert into solid nitrogen. At this time, the refrigerator can be stopped, the magnetic field coil is powered and excited, and the refrigerator can be disconnected from the dewar.

[0025] It is impossible for the Dewar to be completely insulated from the outside world, so after shutdown, the solid nitrogen will absorb external heat and its temperature will gradually rise. Since solid nitrogen has a large latent heat of phase change when heated to 35.6K, it can absorb a large amount of heat while keeping the temperature unchanged. Therefore, the low temperature inside the Dewar can be maintained for a long time, and the magnesium diboride coil can maintain a superconducting state.

[0026] Since the solid nitrogen in the Dewar is solid, it is not afraid of vibration, and the low temperature can be maintained by relying on the latent heat of phase change of solid nitrogen. Therefore, the Dewar and the refrigerator can be disconnected, and the lightweight magnet can be easily moved up and down to the inspection part for scanning.

[0027] There is a temperature sensor in the Dewar. When the temperature of the solid nitrogen in the Dewar rises close to or above 35.6K, it will remind the maintenance personnel to connect the refrigerator as soon as possible to start cooling.

[0028] After the scan is completed, the magnet drops to the lowest position, and the patient can walk out of the magnet and go down the steps to the ground to complete the examination.

[0029] The utility model fundamentally changes the state that patients can only lie flat in the main magnet to be examined, and completely avoids the phenomenon that the imaging results of the body in a non-weight-bearing state will affect the clinical diagnosis or even misdiagnosis or missed diagnosis. Since the superconducting magnet of the utility model is placed vertically to form a vertical magnetic field, the magnet can move up and down to the part that needs to be examined, and the examination results under the weight-bearing state of the body can be obtained, meeting clinical needs.

[0030] Unless otherwise specified or when one preferred or optional technical means is a further limitation of another technical means, the preferred and optional technical means disclosed in the present utility model can be arbitrarily combined to form several different specific implementation methods.

Claims

1. A magnetic resonance imaging system that can be used for examination in an upright weight-bearing state, provided with an MRI magnet and / or an MRI body, provided with a lifting mechanism, characterized in that The MRI magnet and / or the MRI main body are arranged vertically, an upright detection space is arranged in the MRI main body, the MRI main body is vertically movably connected to the base through a lifting mechanism, the MRI magnet is connected to a detachable refrigerator, the MRI magnet is provided with a cooling medium interface for connecting to the refrigerator, the cooling medium is solid nitrogen, the refrigerator matched with the MRI magnet is a detachable refrigerator, the cooling medium interface of the detachable refrigerator and the cooling medium interface of the MRI magnet adopt mutually matching quick-connect structures, the refrigerator is allowed / can be disconnected from the main magnet after the temperature of the solid nitrogen cooled by the refrigerator is lower than 35.6K, and when the temperature of the solid nitrogen is close to or higher than 35.6K, the refrigerator is connected to the MRI magnet and starts cooling.

2. The magnetic resonance imaging system according to claim 1, characterized in that The magnetic field in the detection space is a vertical magnetic field.

3. The magnetic resonance imaging system according to claim 1, characterized in that The magnets in MRI facilities use superconducting material magnesium diboride.

4. The magnetic resonance imaging system according to claim 1, characterized in that Solid nitrogen is used as the cooling medium.

5. The magnetic resonance imaging system according to claim 1, characterized in that The overall shape of the MRI magnet and / or the MRI body is an upright ring.

6. The magnetic resonance imaging system according to claim 1, characterized in that A temperature sensor is provided inside the MRI magnet for collecting / obtaining the temperature of the solid nitrogen inside the MRI magnet.

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