Construction method of magnetic resonance imaging (MRI) magnetic shielding room for medical imaging department

Abstract

The invention relates to a construction method of an MRI (Magnetic Resonance Imaging) magnetic shielding room for a medical imaging department, which comprises the following steps of: determining the position of a magnet bearing foundation on a base layer, paving a silicon steel plate at the position, constructing the magnet bearing foundation, backfilling the periphery of the magnet bearing foundation, and constructing a damp-proof layer on the whole surface after backfilling. Then silicon steel plates are laid on the periphery except the magnet bearing foundation, then construction of an insulating layer is conducted, galvanized steel plates are adopted to be assembled into a shielding chamber shell to be placed on the insulating layer, and the galvanized steel plates are attached through folded edges at the edges and fixedly connected through bolts; distances are reserved between the peripheral side walls and the top of the shielding chamber shell and the building main body; after construction of the shielding room shell is completed, a wood keel is installed on the wall face of the shell, a ceiling keel is installed on the top face of the shell, the space between the wood keel and the wall face of the shell is filled with a rock wool layer, and the outer side of the wood keel, the outer side of the ceiling keel and a bottom plate of the shielding room shell are respectively subjected to construction of a wall face decoration surface layer, a ceiling plate and a ground decoration surface layer.

Description

Technical Field

[0001] The invention relates to the field of building construction, and in particular to a construction method for a magnetic shielding room of a nuclear magnetic resonance (MRI) of a medical imaging department. Background Art

[0002] Magnetic resonance imaging (MRI) is a medical imaging technology used by the hospital's radiology department. The use of MRI scanners is extremely demanding on the surrounding environment, because the surrounding electromagnetic interference will affect the stability of MRI imaging, resulting in poor imaging quality. To solve this problem, a magnetic shielding room is usually set up to place the MRI scanner.

[0003] The construction quality and construction cost of magnetic shielding rooms are the key concerns in the construction process of building projects. The shell of magnetic shielding rooms in the prior art is usually full-welded with copper plates. The expensive copper plates make the shielding room costly. In addition, since the copper plates used are thin, the welding quality is difficult to control during full welding, which easily leads to quality defects such as burn-through, pits, collapse and incomplete filling of the parent material. In addition, the full welding construction speed is slow and the construction period is long. The insulation, waterproofing and electromagnetic interference shielding of magnetic shielding rooms will affect the imaging quality of nuclear magnetic resonance. Therefore, the present invention aims to improve the construction quality of magnetic shielding rooms and reduce the construction cost, thereby providing a construction method for magnetic shielding rooms for nuclear magnetic resonance (MRI) in the medical imaging department. Summary of the invention

[0004] In order to achieve the above object, the technical solution adopted by the present invention is: A construction method for a magnetic shielding room for a nuclear magnetic resonance (MRI) magnetic resonance imaging (MRI) medical imaging department comprises the following steps: Step 1): Complete the construction and surface treatment of the ground base; Step 2): Base surface line positioning, determine the location of the magnet bearing foundation for placing the nuclear magnetic resonance instrument on the ground base by line positioning; Step 3): Lay silicon steel plates at the location of the magnet bearing foundation; Step 4): Carry out the construction of the magnet bearing foundation; Step 5): Backfill the perimeter of the magnet bearing foundation; Step 6): After completing step 5), a moisture-proof layer is constructed on the ground; Step 7): Lay silicon steel plates around the top surface of the moisture-proof layer except for the magnet bearing foundation; Step 8): Lay an insulating layer on the ground after completing step 7); Step 9): Assemble the shielding room shell. The shielding room shell is assembled with galvanized steel plates. The edges of the galvanized steel plates are folded. Holes are opened on the folded edges. The folded edges between adjacent galvanized steel plates are correspondingly fitted and connected by bolts passing through the holes on the folded edges. The side walls and top surface of the assembled shielding room shell are each spaced apart from the main body of the building. Step 10): Install wooden keels on the inner wall surface of the shielding room shell, and install ceiling keels on the inner top surface of the shielding room shell; Step 11): Complete the installation of the wall decoration surface layer, floor decoration surface layer and ceiling panel of the shielding room shell respectively.

[0005] Furthermore, in step 3), the thickness of the silicon steel sheet is not less than 0.5 mm, and a total of eight layers of silicon steel sheets are laid.

[0006] Furthermore, in the step 4), the magnet bearing foundation is formed by pouring plain concrete mixed with 20% fly ash cement, and the height of the formed magnet bearing foundation is not less than 300 mm.

[0007] Furthermore, in the step 5), foamed concrete is used for backfilling, and the backfilling height of the foamed concrete is until it is flush with the top surface of the magnet bearing foundation.

[0008] Furthermore, in step 6), the moisture-proof layer adopts SBS waterproof membrane, and the SBS waterproof membrane is laid in two layers, each layer of SBS waterproof membrane is laid in a patchwork manner, and the upper and lower layers of SBS waterproof membrane are laid with staggered seams. The edges of the SBS waterproof membrane are turned up to the wall masonry of the main building, and the turned-up height of the SBS waterproof membrane is not less than 500 mm.

[0009] Furthermore, in the step 7), the silicon steel plates are laid within 0.5 mT outside the magnet bearing foundation, the thickness of the silicon steel plates is not less than 0.5 mm, and eight layers of silicon steel plates are laid from top to bottom.

[0010] Furthermore, in the step 8), the insulation layer is made of PVC insulation coil, the PVC insulation coil is constructed by seam joining, and the seams are fixed with tape.

[0011] Furthermore, in the step 9), the thickness of the galvanized steel plate is not less than 1.5 mm. When the size of the galvanized steel plate is greater than 1.2 m, a stiffening rib is provided in the middle of the galvanized steel plate. The distance between the side wall of the shielding room shell and the wall masonry of the main building is 80 mm to 100 mm. The distance between the top surface of the shielding room shell and the roof of the main building is controlled to be above 1000 mm.

[0012] Further, in the step 10), the wooden keel is fixed to the folded edge or stiffening rib of the galvanized steel plate by screws through angle joints, and a rock wool layer is filled between the wooden keel and the wall of the shielding room shell; the ceiling keel is made of aluminum alloy, and the ceiling keel is connected to the top of the shielding room shell through a hanging screw rod, a U-shaped clamp is installed on the ceiling keel, the lower end of the hanging screw rod is fixed to the U-shaped clamp with bolts, and the upper end of the hanging screw rod is fixed to the folded edge 2 or stiffening rib 3 of the galvanized steel plate 1 with bolts.

[0013] Furthermore, in step 11), the wall decoration surface layer is made of wooden strips, which are fixed to the wooden keel with nails; the floor decoration surface layer is paved with PVC floor boards, which are fixed with self-tapping screws; and the ceiling board is made of anti-oxidation aluminum alloy sound-absorbing board.

[0014] The magnetic shielding room designed by the present invention adopts galvanized steel plates to replace the copper plates in the prior art to assemble the shell of the shielding room, which can not only save 1 / 2 of the cost, but also avoid deformation of the shell. The shell is spliced ​​by galvanized steel plates with folded edges, and only needs to be connected by bolts. The installation is convenient and quick, and the construction speed and quality can be improved. The present invention also lays silicon steel plates on the bottom of the shielding room shell to enhance the magnetic induction intensity, which can improve the effect of hydrogen atomic nuclear resonance, thereby improving the imaging quality of the nuclear magnetic resonance instrument placed on the upper part of the magnet bearing base. The present invention also prevents the shielding room from losing its insulation effect due to water ingress through the provision of a waterproof layer and an insulating layer, and avoids the nuclear magnetic resonance imaging from being affected by static electricity. Furthermore, the surroundings and the top of the shielding room shell are spaced a certain distance from the main body of the building, so that the shielding room becomes an independent space and is not affected by thunderstorm weather. The galvanized steel plates used in the shell can block the interference of external electromagnetic fields. The above-mentioned structural design of the present invention effectively guarantees the quality and stability of nuclear magnetic resonance imaging. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 is a vertical partial cross-sectional view of a nuclear magnetic resonance shielding room in an embodiment; Figure 2 This is a schematic diagram of the structure in which the shielding room shell is connected by galvanized steel plates; Figure 3 for Figure 2 Top view of the galvanized steel plate hem joint.

[0016] Reference numerals: 1. Galvanized steel plate; 2. Folded edge; 3. Stiffening rib; 4. Galvanized bolt; 5. Gasket; 6. Galvanized nut; 7. Magnet load-bearing foundation; 8. Foam concrete; 9. Wall masonry; 10. Waterproof membrane; 11. Silicon steel plate; 12. PVC insulation membrane; 13. PVC floor board; 14. Self-tapping screws; 15. Corner joint; 16. Wooden keel; 17. Rock wool layer; 18. Wall decoration surface layer; 19. Floor decoration surface layer. DETAILED DESCRIPTION

[0017] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the accompanying drawings in the embodiments of the present invention.

[0018] This embodiment discloses a construction method of a magnetic shielding room for a medical imaging department's nuclear magnetic resonance (MRI) magnetic shielding room. The core structure of the magnetic shielding room is as follows: Figure 1 As shown ( Figure 1 To simplify the schematic diagram, only the partial cross-sectional structure of the shielding room floor and wall is shown, and the schematic diagram of the shielding room top is omitted). The structure and construction method of the entire magnetic shielding room are as follows: Step 1): Complete the construction and surface treatment of the ground base; first, thoroughly clean the garbage on the surface of the base, and then fill or flatten the uneven parts of the base surface to ensure the surface flatness after the base treatment.

[0019] Step 2): Base surface positioning by marking lines. The position of the magnet bearing foundation 7 for placing the nuclear magnetic resonance apparatus is determined by marking lines on the ground base layer; according to the position of the magnet bearing foundation 7 in the design drawing, it is measured and laid out to determine the position of the magnet bearing foundation 7. After elastic positioning on the base surface, measurement and verification are performed.

[0020] Step 3): Lay silicon steel plates 11 at the location of the magnet load-bearing foundation 7; the thickness of the silicon steel plates 11 is not less than 0.5 mm. The thickness of the silicon steel plates 11 in this embodiment is 0.5 mm. Because the location of the magnet load-bearing foundation 7 is used to place a nuclear magnetic resonance apparatus, no ferromagnetic material is allowed within 300 mm below the nuclear magnetic resonance apparatus. Therefore, in this embodiment, a total of eight layers of silicon steel plates 11 are laid at the magnet load-bearing foundation 7.

[0021] Step 4): Carry out the construction of the magnet bearing foundation 7; The size and concrete type of the magnet load-bearing foundation 7 are constructed according to the equipment parameter requirements provided by the manufacturer of the nuclear magnetic resonance instrument. The height of the magnet load-bearing foundation 7 is not less than 300mm. The magnet load-bearing foundation 7 can be formed by pouring plain concrete mixed with 20% fly ash cement. The concrete strength grade shall not be less than C25. Formwork is required during pouring to ensure that the size of the magnet load-bearing foundation 7 after construction meets the design requirements.

[0022] During construction, the temperature of concrete membrane shall not be lower than 5℃ and higher than 35℃. Curing shall be carried out before the final setting of concrete. The curing temperature shall be controlled at 20±2℃. The relative humidity during curing shall be maintained above 95%. The curing time shall not be less than 7 days. The concrete strength shall not reach 1.2N / mm 2 Before construction, no one shall step on it. No cracks shall appear on the surface of the magnet bearing foundation 7 after construction is completed to ensure its design strength requirements.

[0023] Step 5): Backfill the periphery of the magnet bearing foundation 7; This embodiment uses foamed concrete 8 for backfilling, and the backfill height of the foamed concrete 8 is flush with the top surface of the magnet bearing foundation 7. The foamed concrete 8 has the characteristics of light weight and low elasticity, which can greatly reduce the post-settlement of the backfill area, and can effectively ensure the stability of the nuclear magnetic resonance instrument. The foamed concrete 8 also has heat insulation, fire resistance and shock absorption, as well as good durability and waterproof effects. The pouring construction of the foamed concrete 8 should be above the ambient temperature of 5°C. After it is fully solidified and dried, the surface flatness of the foamed concrete 8 is measured, and the surface flatness error shall not be greater than 5mm.

[0024] Step 6): After completing step 5), a moisture-proof layer is constructed on the ground; The moisture-proof layer in this embodiment adopts SBS waterproofing membrane 10. SBS waterproofing membrane not only has good waterproofing effect, but also has certain insulation effect, which avoids the loss of insulation effect caused by accidental water ingress in the shielding room, and further avoids the influence of static electricity on nuclear magnetic resonance imaging. In order to ensure good waterproofing effect, the SBS waterproofing membrane 10 in this embodiment is laid in two layers, and each layer of SBS waterproofing membrane 10 can only be laid in a jointing manner, and it is not allowed to be laid in a overlapping manner. When laying, the upper and lower layers of SBS waterproofing membrane 10 must be staggered, and the joints of the two layers of moisture-proof layers should be staggered by more than 400mm. In order to prevent moisture from returning to the wall, this embodiment also turns the edges of the SBS waterproofing membrane 10 up to the wall masonry 9 in the main body of the building, and the turning height of the SBS waterproofing membrane 10 is not less than 500mm. The moisture-proof layer is constructed by hot melt method, and the thickness of the SBS waterproofing membrane 10 shall not be less than 3mm. After the surface of the SBS waterproof membrane 10 is hot-melted, the membrane should be rolled out immediately and rolled and bonded firmly, and no hollows should be allowed between the membrane and the surface of the foam concrete 8.

[0025] Step 7): Lay silicon steel plates 11 on the top surface of the moisture-proof layer within a range of 0.5mT (magnetic field with a magnetic field strength of 0.5 millitesla) except for the magnet bearing foundation 7; the thickness of the silicon steel plates 11 laid in this step is not less than 0.5mm, and a total of eight layers of silicon steel plates 11 are laid from top to bottom.

[0026] Since the machinery and equipment outside the shielding room will interfere with the magnetic field, causing the magnetic field to change, which will interfere with the quality of MRI. The maximum allowable magnetic flux density depends on the sensitivity of the equipment. Through calculation, it can be known that the minimum distance allowed within the range of 0.5mT is 2.5m in the XY radial direction and 4m in the Z axis direction. Laying silicon steel plates 11 within this range can reduce hysteresis loss, enhance magnetic induction intensity, and improve the effect of hydrogen nucleus resonance, making the specific frequency electrical signal emitted by the hydrogen nucleus in the human body stronger, so it is easier to be recorded by the receiver.

[0027] Step 8): Lay an insulating layer on the ground after completing step 7); The insulating layer in this embodiment uses PVC insulating coil 12, which has good electrical insulation performance, so that the bottom of the shielding room shell and the floor of the MRI room have excellent insulation effect, avoiding interference with the quality of MRI imaging due to static electricity. In order to ensure the flatness of the floor, the PVC insulating coil 12 is seamed during laying, and overlapping seams are not allowed. After the seams are completed, the seams are fixed with transparent tape in time, and rolled with a roller in time. It is strictly forbidden to have gaps between the PVC insulating coil 12 and the contact surface.

[0028] Step 9): Assemble the shielding room shell; The entire shielding room shell in this embodiment is a square closed structure, and the shielding room shell is assembled by splicing galvanized steel plates 1. The electromagnetic waves outside the shielding room shell will be attracted by the free electrons in the galvanized steel plates 1 and slow down their propagation speed. Therefore, the galvanized steel plates 1 play a role in blocking the interference of the electromagnetic field outside the shielding room. The galvanized steel plates 1 are harder and cheaper than copper plates, which is very beneficial for reducing costs. In order to increase the assembly speed of the shielding room shell, the galvanized steel plates 1 in this embodiment are as follows. Figure 2 and Figure 3 As shown, the edges of each galvanized steel sheet 1 are bent to form a hem 2, and holes are opened on the hem 2. When galvanized steel sheets 1 are assembled, the hems 2 of adjacent galvanized steel sheets 1 are correspondingly fitted together and connected by galvanized bolts 4 passing through the holes on the hems. Gaskets 5 are respectively set on both sides of the fitted hems 2 on the galvanized bolts 4, and then locked with galvanized nuts 6. The thickness of the galvanized steel sheet 1 is not less than 1.5 mm. For large-sized galvanized steel sheets 1, such as those with a width greater than 1.2 m, stiffening ribs 3 can be set in the middle of the galvanized steel sheet 1 to avoid unstable deformation during transportation and installation.

[0029] A certain distance must be left between the side wall and the top surface of the assembled shielding room shell and the main building to avoid contact between the two, so as to ensure the insulation effect of the shielding room shell. In this embodiment, the distance between the side wall of the shielding room shell and the wall masonry 9 is 80mm-100mm, and the distance between the top surface of the shielding room shell and the roof of the main building is controlled to be more than 1000mm.

[0030] Step 10): After the construction and installation of the shielding room shell is completed, a wooden keel 16 is installed on the inner wall surface of the shielding room shell, and a ceiling keel is installed on the inner top surface of the shielding room shell (not shown in the figure); In this embodiment, the wooden keel 16 is fixed to the folded edge 2 or the stiffening rib 3 of the galvanized steel plate 1 by screws through the corner joint 15. Since the fire resistance of the galvanized steel plate 1 is poor, in this embodiment, a rock wool layer 17 is filled between the wall of the shielding room shell within the ceiling height range and the wooden keel 16, which effectively guarantees the fire prevention and control capability of the shielding room, and the rock wool layer 17 has good sound absorption and sound insulation effects, which can reduce the noise interference of the nuclear magnetic resonance apparatus to the external environment when working.

[0031] The shielding room should try to avoid ferromagnetic metals, which will interfere with nuclear magnetic resonance. The ceiling keel in this embodiment is made of aluminum alloy. The ceiling keel is connected to the top of the shielding room shell through a hanging screw rod. A U-shaped clamp is installed on the ceiling keel. The lower end of the hanging screw rod is bolted to the U-shaped clamp, and the upper end of the hanging screw rod is bolted to the folded edge 2 or stiffening rib 3 of the galvanized steel plate 1. When constructing the hanging screw rod, the verticality of each hanging screw rod should be guaranteed, and the fixed height of the aluminum alloy ceiling keel should be ensured to be in the same horizontal plane. Only in this way can the pulling force on each ceiling board be the same, and the carrying capacity of the hanging screw rod can be fully exerted.

[0032] Step 11): Complete the installation of the wall decoration surface layer 18, the floor decoration surface layer 19 and the ceiling panel of the shielding room shell respectively.

[0033] The wall decoration surface layer 18 in this embodiment is made of wooden strips, which are fixed to the wooden keel 16 by nailing. A PVC floor board 13 is laid on the bottom surface of the shielding room shell as the floor decoration surface layer 19, and the PVC floor board 13 is fixed by self-tapping screws 14. The PVC floor board has good fireproof performance and good wear resistance. A ceiling board is set at the lower part of the ceiling keel. In this embodiment, the ceiling board is made of anti-oxidation aluminum alloy sound-absorbing board, which has good fireproof performance and good sound absorption effect.

[0034] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A construction method for a magnetic shielding room for a medical imaging department's nuclear magnetic resonance (MRI) magnetic resonance imaging (MRI) magnetic shielding room, characterized in that: The steps include: Step 1): Complete the construction and surface treatment of the ground base; Step 2): Base surface line positioning, determine the location of the magnet bearing foundation for placing the nuclear magnetic resonance instrument on the ground base by line positioning; Step 3): Lay silicon steel plates at the location of the magnet bearing foundation; Step 4): Carry out the construction of the magnet bearing foundation; Step 5): Backfill the perimeter of the magnet bearing foundation; Step 6): After completing step 5), a moisture-proof layer is constructed on the ground; Step 7): Lay silicon steel plates around the top surface of the moisture-proof layer except for the magnet bearing foundation; Step 8): Lay an insulating layer on the ground after completing step 7); Step 9): Assemble the shielding room shell. The shielding room shell is assembled with galvanized steel plates. The edges of the galvanized steel plates are folded. Holes are opened on the folded edges. The folded edges between adjacent galvanized steel plates are correspondingly fitted and connected by bolts passing through the holes on the folded edges. The side walls and top surface of the assembled shielding room shell are each spaced apart from the main body of the building. Step 10): Install wooden keels on the inner wall surface of the shielding room shell, and install ceiling keels on the inner top surface of the shielding room shell; Step 11): Complete the installation of the wall decoration surface layer, floor decoration surface layer and ceiling panel of the shielding room shell respectively.

2. The construction method of a magnetic shielding room for a medical imaging department MRI according to claim 1, characterized in that: In the step 3), the thickness of the silicon steel sheet is not less than 0.5 mm, and eight layers of silicon steel sheets are laid.

3. The construction method of a magnetic shielding room for a medical imaging department MRI according to claim 1, characterized in that: In the step 4), the magnet bearing foundation is formed by pouring plain concrete mixed with 20% fly ash cement, and the height of the formed magnet bearing foundation is not less than 300 mm.

4. The construction method of a magnetic shielding room for a medical imaging department MRI according to claim 1, characterized in that: In the step 5), foam concrete is used for backfilling, and the backfilling height of the foam concrete is until it is flush with the top surface of the magnet bearing foundation.

5. The construction method of a magnetic shielding room for a medical imaging department MRI according to claim 1, characterized in that: In the step 6), the moisture-proof layer adopts SBS waterproof membrane, and the SBS waterproof membrane is laid in two layers, each layer of SBS waterproof membrane is laid in a patchwork manner, and the upper and lower layers of SBS waterproof membrane are laid with staggered seams. The edges of the SBS waterproof membrane are turned up to the wall masonry of the main building, and the turned-up height of the SBS waterproof membrane is not less than 500mm.

6. The construction method of a magnetic shielding room for a medical imaging department MRI according to claim 1, characterized in that: In the step 7), the silicon steel plates are laid within 0.5 mT outside the magnet bearing foundation, the thickness of the silicon steel plates is not less than 0.5 mm, and eight layers of silicon steel plates are laid up and down.

7. The construction method of a magnetic shielding room for a medical imaging department MRI according to claim 1, characterized in that: In the step 8), the insulation layer is made of PVC insulation coil, the PVC insulation coil is constructed by seaming, and the seams are fixed with tape.

8. The construction method of a magnetic shielding room for a medical imaging department MRI according to claim 1, characterized in that: In the step 9), the thickness of the galvanized steel plate is not less than 1.5 mm. When the size of the galvanized steel plate is greater than 1.2 m, a stiffening rib is provided in the middle of the galvanized steel plate. The distance between the side wall of the shielding room shell and the wall masonry of the main building is 80 mm to 100 mm. The distance between the top surface of the shielding room shell and the roof of the main building is controlled to be above 1000 mm.

9. The construction method of a magnetic shielding room for a medical imaging department MRI according to claim 8, characterized in that: In the step 10), the wooden keel is fixed to the folded edge or stiffening rib of the galvanized steel plate by screws through angle joints, and a rock wool layer is filled between the wooden keel and the wall of the shielding room shell; the ceiling keel is made of aluminum alloy, and the ceiling keel is connected to the top of the shielding room shell by a hanging screw rod, a U-shaped clamp is installed on the ceiling keel, the lower end of the hanging screw rod is fixed to the U-shaped clamp with bolts, and the upper end of the hanging screw rod is fixed to the folded edge 2 or stiffening rib 3 of the galvanized steel plate 1 with bolts.

10. The construction method of a magnetic shielding room for a medical imaging department MRI according to claim 1, characterized in that: In the step 11), the wall decoration surface layer is made of wooden strips, which are fixed to the wooden keel by nails; the floor decoration surface layer is paved with PVC floor boards, which are fixed with self-tapping screws; and the ceiling board is made of anti-oxidation aluminum alloy sound-absorbing board.

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