CN111691715A - Assembled honeycomb type X-ray diagnosis CT equipment cabin - Google Patents
Assembled honeycomb type X-ray diagnosis CT equipment cabin Download PDFInfo
- Publication number
- CN111691715A CN111691715A CN202010608407.8A CN202010608407A CN111691715A CN 111691715 A CN111691715 A CN 111691715A CN 202010608407 A CN202010608407 A CN 202010608407A CN 111691715 A CN111691715 A CN 111691715A
- Authority
- CN
- China
- Prior art keywords
- cabin
- radiation
- scanning
- rods
- ctdi
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Withdrawn
Links
- 238000003745 diagnosis Methods 0.000 title claims abstract description 18
- 230000005855 radiation Effects 0.000 claims abstract description 97
- 229920001971 elastomer Polymers 0.000 claims abstract description 26
- 230000004224 protection Effects 0.000 claims abstract description 23
- 238000007789 sealing Methods 0.000 claims abstract description 18
- 230000035939 shock Effects 0.000 claims abstract description 15
- 238000010521 absorption reaction Methods 0.000 claims abstract description 14
- 238000009826 distribution Methods 0.000 claims abstract description 14
- 238000002591 computed tomography Methods 0.000 claims description 99
- 238000000034 method Methods 0.000 claims description 38
- 238000013461 design Methods 0.000 claims description 16
- 238000004364 calculation method Methods 0.000 claims description 12
- 238000002360 preparation method Methods 0.000 claims description 12
- 229910052602 gypsum Inorganic materials 0.000 claims description 11
- 239000010440 gypsum Substances 0.000 claims description 11
- 229910000831 Steel Inorganic materials 0.000 claims description 9
- 238000012937 correction Methods 0.000 claims description 9
- 239000010959 steel Substances 0.000 claims description 9
- 229910000838 Al alloy Inorganic materials 0.000 claims description 8
- 229920000459 Nitrile rubber Polymers 0.000 claims description 5
- 238000012545 processing Methods 0.000 claims description 5
- 238000002834 transmittance Methods 0.000 claims description 5
- 244000241796 Christia obcordata Species 0.000 claims description 4
- 229910052797 bismuth Inorganic materials 0.000 claims description 4
- JCXGWMGPZLAOME-UHFFFAOYSA-N bismuth atom Chemical compound [Bi] JCXGWMGPZLAOME-UHFFFAOYSA-N 0.000 claims description 4
- 239000000945 filler Substances 0.000 claims description 4
- WFKWXMTUELFFGS-UHFFFAOYSA-N tungsten Chemical compound [W] WFKWXMTUELFFGS-UHFFFAOYSA-N 0.000 claims description 4
- 229910052721 tungsten Inorganic materials 0.000 claims description 4
- 239000010937 tungsten Substances 0.000 claims description 4
- 229910052688 Gadolinium Inorganic materials 0.000 claims description 3
- 230000002238 attenuated effect Effects 0.000 claims description 3
- 230000008602 contraction Effects 0.000 claims description 3
- 239000002872 contrast media Substances 0.000 claims description 3
- UIWYJDYFSGRHKR-UHFFFAOYSA-N gadolinium atom Chemical compound [Gd] UIWYJDYFSGRHKR-UHFFFAOYSA-N 0.000 claims description 3
- 229920002379 silicone rubber Polymers 0.000 claims description 3
- 239000000126 substance Substances 0.000 claims description 3
- 239000010410 layer Substances 0.000 description 29
- 230000001681 protective effect Effects 0.000 description 17
- 238000011282 treatment Methods 0.000 description 7
- 239000000463 material Substances 0.000 description 6
- 238000009423 ventilation Methods 0.000 description 6
- 238000007689 inspection Methods 0.000 description 5
- 230000000694 effects Effects 0.000 description 4
- 230000007613 environmental effect Effects 0.000 description 4
- 230000009977 dual effect Effects 0.000 description 3
- 238000010438 heat treatment Methods 0.000 description 3
- 238000005259 measurement Methods 0.000 description 3
- 238000004806 packaging method and process Methods 0.000 description 3
- 239000004925 Acrylic resin Substances 0.000 description 2
- 229920000178 Acrylic resin Polymers 0.000 description 2
- 241001653766 Neolaugeria resinosa Species 0.000 description 2
- 210000001015 abdomen Anatomy 0.000 description 2
- 230000003187 abdominal effect Effects 0.000 description 2
- 230000005540 biological transmission Effects 0.000 description 2
- 238000011156 evaluation Methods 0.000 description 2
- 238000009434 installation Methods 0.000 description 2
- 238000012423 maintenance Methods 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 210000000056 organ Anatomy 0.000 description 2
- 239000011241 protective layer Substances 0.000 description 2
- 238000004378 air conditioning Methods 0.000 description 1
- 238000004458 analytical method Methods 0.000 description 1
- 210000001367 artery Anatomy 0.000 description 1
- 230000033228 biological regulation Effects 0.000 description 1
- 230000000747 cardiac effect Effects 0.000 description 1
- 238000004891 communication Methods 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 230000001276 controlling effect Effects 0.000 description 1
- 238000002586 coronary angiography Methods 0.000 description 1
- 230000002354 daily effect Effects 0.000 description 1
- 238000013480 data collection Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000012941 design validation Methods 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000003203 everyday effect Effects 0.000 description 1
- 239000000295 fuel oil Substances 0.000 description 1
- 150000002251 gadolinium compounds Chemical class 0.000 description 1
- 230000002070 germicidal effect Effects 0.000 description 1
- 230000036541 health Effects 0.000 description 1
- RVRCFVVLDHTFFA-UHFFFAOYSA-N heptasodium;tungsten;nonatriacontahydrate Chemical compound O.O.O.O.O.O.O.O.O.O.O.O.O.O.O.O.O.O.O.O.O.O.O.O.O.O.O.O.O.O.O.O.O.O.O.O.O.O.O.[Na+].[Na+].[Na+].[Na+].[Na+].[Na+].[Na+].[W].[W].[W].[W].[W].[W].[W].[W].[W].[W].[W] RVRCFVVLDHTFFA-UHFFFAOYSA-N 0.000 description 1
- 230000003902 lesion Effects 0.000 description 1
- 230000007774 longterm Effects 0.000 description 1
- 230000014759 maintenance of location Effects 0.000 description 1
- 230000000877 morphologic effect Effects 0.000 description 1
- 238000005457 optimization Methods 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 238000005192 partition Methods 0.000 description 1
- 230000007170 pathology Effects 0.000 description 1
- 239000011148 porous material Substances 0.000 description 1
- 230000005180 public health Effects 0.000 description 1
- 238000003908 quality control method Methods 0.000 description 1
- 230000001950 radioprotection Effects 0.000 description 1
- 230000001105 regulatory effect Effects 0.000 description 1
- 239000004945 silicone rubber Substances 0.000 description 1
- 238000003860 storage Methods 0.000 description 1
- 238000002636 symptomatic treatment Methods 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
- 238000012795 verification Methods 0.000 description 1
- 210000001835 viscera Anatomy 0.000 description 1
- 230000003442 weekly effect Effects 0.000 description 1
Images
Classifications
-
- E—FIXED CONSTRUCTIONS
- E04—BUILDING
- E04H—BUILDINGS OR LIKE STRUCTURES FOR PARTICULAR PURPOSES; SWIMMING OR SPLASH BATHS OR POOLS; MASTS; FENCING; TENTS OR CANOPIES, IN GENERAL
- E04H3/00—Buildings or groups of buildings for public or similar purposes; Institutions, e.g. infirmaries or prisons
- E04H3/08—Hospitals, infirmaries, or the like; Schools; Prisons
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
- A61B6/00—Apparatus or devices for radiation diagnosis; Apparatus or devices for radiation diagnosis combined with radiation therapy equipment
- A61B6/10—Safety means specially adapted therefor
- A61B6/102—Protection against mechanical damage, e.g. anti-collision devices
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
- A61B6/00—Apparatus or devices for radiation diagnosis; Apparatus or devices for radiation diagnosis combined with radiation therapy equipment
- A61B6/10—Safety means specially adapted therefor
- A61B6/107—Protection against radiation, e.g. shielding
-
- E—FIXED CONSTRUCTIONS
- E04—BUILDING
- E04B—GENERAL BUILDING CONSTRUCTIONS; WALLS, e.g. PARTITIONS; ROOFS; FLOORS; CEILINGS; INSULATION OR OTHER PROTECTION OF BUILDINGS
- E04B1/00—Constructions in general; Structures which are not restricted either to walls, e.g. partitions, or floors or ceilings or roofs
- E04B1/343—Structures characterised by movable, separable, or collapsible parts, e.g. for transport
-
- E—FIXED CONSTRUCTIONS
- E04—BUILDING
- E04B—GENERAL BUILDING CONSTRUCTIONS; WALLS, e.g. PARTITIONS; ROOFS; FLOORS; CEILINGS; INSULATION OR OTHER PROTECTION OF BUILDINGS
- E04B1/00—Constructions in general; Structures which are not restricted either to walls, e.g. partitions, or floors or ceilings or roofs
- E04B1/343—Structures characterised by movable, separable, or collapsible parts, e.g. for transport
- E04B1/34315—Structures characterised by movable, separable, or collapsible parts, e.g. for transport characterised by separable parts
- E04B1/34326—Structures characterised by movable, separable, or collapsible parts, e.g. for transport characterised by separable parts mainly constituted by longitudinal elements
-
- E—FIXED CONSTRUCTIONS
- E04—BUILDING
- E04B—GENERAL BUILDING CONSTRUCTIONS; WALLS, e.g. PARTITIONS; ROOFS; FLOORS; CEILINGS; INSULATION OR OTHER PROTECTION OF BUILDINGS
- E04B1/00—Constructions in general; Structures which are not restricted either to walls, e.g. partitions, or floors or ceilings or roofs
- E04B1/343—Structures characterised by movable, separable, or collapsible parts, e.g. for transport
- E04B1/344—Structures characterised by movable, separable, or collapsible parts, e.g. for transport with hinged parts
- E04B1/3441—Structures characterised by movable, separable, or collapsible parts, e.g. for transport with hinged parts with articulated bar-shaped elements
-
- E—FIXED CONSTRUCTIONS
- E04—BUILDING
- E04B—GENERAL BUILDING CONSTRUCTIONS; WALLS, e.g. PARTITIONS; ROOFS; FLOORS; CEILINGS; INSULATION OR OTHER PROTECTION OF BUILDINGS
- E04B1/00—Constructions in general; Structures which are not restricted either to walls, e.g. partitions, or floors or ceilings or roofs
- E04B1/348—Structures composed of units comprising at least considerable parts of two sides of a room, e.g. box-like or cell-like units closed or in skeleton form
-
- E—FIXED CONSTRUCTIONS
- E04—BUILDING
- E04B—GENERAL BUILDING CONSTRUCTIONS; WALLS, e.g. PARTITIONS; ROOFS; FLOORS; CEILINGS; INSULATION OR OTHER PROTECTION OF BUILDINGS
- E04B1/00—Constructions in general; Structures which are not restricted either to walls, e.g. partitions, or floors or ceilings or roofs
- E04B1/62—Insulation or other protection; Elements or use of specified material therefor
- E04B1/92—Protection against other undesired influences or dangers
-
- E—FIXED CONSTRUCTIONS
- E04—BUILDING
- E04B—GENERAL BUILDING CONSTRUCTIONS; WALLS, e.g. PARTITIONS; ROOFS; FLOORS; CEILINGS; INSULATION OR OTHER PROTECTION OF BUILDINGS
- E04B1/00—Constructions in general; Structures which are not restricted either to walls, e.g. partitions, or floors or ceilings or roofs
- E04B1/62—Insulation or other protection; Elements or use of specified material therefor
- E04B1/92—Protection against other undesired influences or dangers
- E04B1/98—Protection against other undesired influences or dangers against vibrations or shocks; against mechanical destruction, e.g. by air-raids
-
- E—FIXED CONSTRUCTIONS
- E04—BUILDING
- E04H—BUILDINGS OR LIKE STRUCTURES FOR PARTICULAR PURPOSES; SWIMMING OR SPLASH BATHS OR POOLS; MASTS; FENCING; TENTS OR CANOPIES, IN GENERAL
- E04H9/00—Buildings, groups of buildings or shelters adapted to withstand or provide protection against abnormal external influences, e.g. war-like action, earthquake or extreme climate
- E04H9/02—Buildings, groups of buildings or shelters adapted to withstand or provide protection against abnormal external influences, e.g. war-like action, earthquake or extreme climate withstanding earthquake or sinking of ground
- E04H9/021—Bearing, supporting or connecting constructions specially adapted for such buildings
-
- E—FIXED CONSTRUCTIONS
- E04—BUILDING
- E04B—GENERAL BUILDING CONSTRUCTIONS; WALLS, e.g. PARTITIONS; ROOFS; FLOORS; CEILINGS; INSULATION OR OTHER PROTECTION OF BUILDINGS
- E04B1/00—Constructions in general; Structures which are not restricted either to walls, e.g. partitions, or floors or ceilings or roofs
- E04B1/62—Insulation or other protection; Elements or use of specified material therefor
- E04B1/92—Protection against other undesired influences or dangers
- E04B2001/925—Protection against harmful electro-magnetic or radio-active radiations, e.g. X-rays
Landscapes
- Engineering & Computer Science (AREA)
- Architecture (AREA)
- Physics & Mathematics (AREA)
- Structural Engineering (AREA)
- Civil Engineering (AREA)
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Electromagnetism (AREA)
- Medical Informatics (AREA)
- Environmental & Geological Engineering (AREA)
- Public Health (AREA)
- Heart & Thoracic Surgery (AREA)
- Veterinary Medicine (AREA)
- Molecular Biology (AREA)
- Surgery (AREA)
- Animal Behavior & Ethology (AREA)
- General Health & Medical Sciences (AREA)
- Radiology & Medical Imaging (AREA)
- Biomedical Technology (AREA)
- Pathology (AREA)
- Business, Economics & Management (AREA)
- Emergency Management (AREA)
- Optics & Photonics (AREA)
- Nuclear Medicine, Radiotherapy & Molecular Imaging (AREA)
- High Energy & Nuclear Physics (AREA)
- Biophysics (AREA)
- Apparatus For Radiation Diagnosis (AREA)
Abstract
The invention provides an assembled honeycomb type X-ray diagnosis CT equipment cabin, which comprises a hexagonal three-dimensional cabin, wherein the two cabins are mutually communicated through side edges, and each cabin comprises: the top component comprises six top rods which are connected with each other and a top angle which is formed by inclined rods which are respectively led out upwards from the connecting angle; the bottom component comprises six bottom rods forming side edges and bottom rib rods respectively connected with the connecting corners; the side component comprises main rods and fences connected with the two main rods; the sealing plate comprises a sealing plate, a shielding layer made of lead-free radiation-proof rubber and a shock absorption structure layer; a CT device. The invention sets the components of the cabin as independent components with uniform specification, and forms the hexagonal cabin by assembling when in use. The lead-free radiation-resistant rubber is adopted as the shielding layer, so that the transportation burden can be reduced, and the environment cannot be polluted. By correcting the distribution of the radiation field, the working position can be arranged at the place with the least irradiation amount, and the protection for personnel is improved.
Description
Technical Field
The invention relates to the field of radiology, in particular to an assembled honeycomb type X-ray diagnosis CT equipment cabin which has a detachable structure and can reasonably install CT equipment.
Background
The X-ray diagnostic equipment used as a medical computed tomography system (CT system for short) can almost acquire the pathology of all internal organs of a human body and the morphological information of the organs and lesions of the human body, and is important modern diagnosis and treatment auxiliary equipment. When a serious natural disaster or a sudden public health incident occurs, the number of people in a short period of time is greatly increased due to the disaster and epidemic situation, and CT medical image inspection resources are often seriously squeezed. Aiming at the situation, the on-site simple X-ray diagnosis and treatment radiation shelter which is transformed by a container lead plate application mode is used at present, the on-site simple X-ray diagnosis and treatment radiation shelter can be used for performing near and early detection on a large number of patients in time, plays a great role in rapid classification diagnosis and treatment and symptomatic treatment of light and severe patients, and has some defects.
Firstly, the current vehicle-mounted or square cabin type CT system is generally very heavy, generally the length of the body is about 10-18 meters, and after the weight of a protective wall (lead plate) is added, the total weight of the system exceeds 3-4 tons and even more than 10 tons, which is equivalent to moving an installed CT machine room to a use place, not only the mobility is poor and the cost is high, but also potential safety threats exist in the transportation, installation, maintenance and construction processes. And lead-containing material components used in the field environment are easy to cause secondary pollution, and have potential environmental threats in long-term use.
Secondly, such simple shelter is mainly a rigid structural member, and the CT equipment and the cabin are fixed by rigid connection, so that the stability of the CT system can be influenced once the equipment link is damaged or the cabin is deformed due to the jolt of a long-distance transportation path, and therefore, the existing structure has high requirements on shock absorption, and the equipment is high in leveling and calibration difficulty and cannot be used in a field environment or an area with inconvenient traffic.
In addition, because the radiation field distribution difference between the CT machine and the point source is large, the shielding protection structures such as a cube and a cuboid cannot well solve the contradiction between the radiation protection requirement and layout optimization, not only increases the load of the vehicle, but also cannot use more than 16 rows of high-speed spiral CT due to space limitation, and the diagnosis and treatment efficiency is low.
Disclosure of Invention
The invention aims to provide an assembled honeycomb type X-ray diagnosis CT equipment cabin which has a detachable structure and can reasonably install CT equipment.
Specifically, the invention provides a honeycomb type X-ray diagnosis CT equipment shelter, which comprises a hexagonal three-dimensional cabin, wherein the two cabins are communicated with each other through side edges, and each cabin comprises:
the top component is of a frame structure and comprises a symmetrical hexagonal plane frame formed by connecting six top rods and a top angle formed by inclined rods led out upwards at each connecting angle;
the bottom component is a hexagonal plane frame corresponding to the plane frame of the top component in size and shape, and comprises bottom rods forming side edges and bottom rib rods respectively connected with the connecting corners of the bottom rods;
the side component is a rectangular plane frame which is respectively connected with the top component plane frame and the bottom component plane frame, and comprises main rods which are respectively connected with two ends of the corresponding top rod and the corresponding bottom rod, and fences which are connected with the two main rods;
the sealing plate comprises a sealing plate for sealing the top component and the side component, a shielding layer made of lead-free radiation-proof rubber, and a shock absorption structure layer for sealing the bottom component;
the CT equipment comprises a scanning cabin, a control room and a preparation room, and the arrangement positions of the scanning cabin, the control room and the preparation room in the cabin are determined according to the radiation field distribution given by the national standard when the scanning cabin works and correction.
In one embodiment of the present invention, the top member has connecting rods installed in the plane of the planar frame to connect the opposite connecting angles, respectively, each connecting rod forms a cross point at the center of the planar frame, and one diagonal rod is connected between the middle of each diagonal rod and the cross point.
In one embodiment of the invention, the top, bottom and side members are connected to each other by hinges.
In one embodiment of the invention, the top member and the side members are made of aluminum alloy sections, the closing plate is a gypsum board or an aluminum alloy plate, and when the gypsum board is adopted, the thickness of the closing plate is 220-270 mm, and the density of the closing plate is 0.705g/cm3。
In one embodiment of the invention, the bottom member is made of angle steel, the shock absorption structure layer comprises a shock absorption flat plate laid on the surface of the angle steel, a lead rubber protection layer laid on the shock absorption flat plate, and a shock absorption bracket for adjusting and debugging is installed at the bottom of the angle steel.
In one embodiment of the invention, the lead-free radiation-proof rubber of the shielding layer is made of one or more of tungsten, bismuth and gadolinium as aggregate and nitrile rubber or silicone rubber as filler, and the thickness of the lead-free radiation-proof rubber is that2 to 5mm, a specific lead equivalent of 0.3 to 0.5mmPb/mm, and a density of 4.73 to 5.01g/cm3。
In one embodiment of the invention, the single side of the cabin has a length of at least 4.5m and a height of 2.7-3.3 m.
In one embodiment of the present invention, the processing steps of the radiation field distribution during operation of the scan bin according to the national standard and performing the correction are as follows:
step 200, respectively calculating the shielding thickness value of each concerned point by utilizing a CT dose index workload method and a CT dose length product workload method, carrying out reference comparison, then taking the position of a middle balance point, and placing a scanning bin in a mode of being vertical to the connecting surface of two cabins;
In one embodiment of the present invention, the CT dose index (CTDI)100) The calculation process of the workload method is as follows:
calculating the CT dose index (CTDI) using the following formula100) Relationship to weighted CT dose index:
wherein, CTDIWTo weight CT dose index, CTDI100，centerCTDI centered on the mold body100Value, CTDI100，peripheryIs the mold body periphery CTDI100The unit of the value, three is: mGy;
calculating the radiation transmittance B at the focus point outside the shielding body:
wherein, P is a mask design target value, unit: mSv/week; d is the distance from the focus of interest outside the shielding body to the scanning center, and the unit is: m; t is a residence factor of personnel outside the shielding body,
is the air kerma of scattered radiation during CT examination at a scanning center of 1m, unit: mGy/human; n is the number of diagnosed patients, unit: a human;
and finally, obtaining the corresponding shielding thickness values of different focus points.
In one embodiment of the present invention, the first and second electrodes are, in,
the CT dose-length product (DLP) workload method is calculated as follows:
firstly, estimating the estimated shielding thickness of each concern point according to the radiation dose control standard specified in the national standard;
then, the air kerma scattered radiation share of the CT is calculated by the following formula, and the DLP value is determined according to the national standard:
wherein the content of the first and second substances,
is the kinetic energy of the air kerma from scattered radiation generated under the condition of head scanning at the scanning center of 1m, unit: mGy/human;
is the kinetic energy of the air kerma from the scattered radiation generated under the condition of scanning the body at the scanning center 1m, unit: mGy/human; kappa is a proportionality constant;
and correcting the DLP value according to the influence caused by using and not using the contrast agent to obtain the corresponding shielding thickness values of different focus points.
The top member, the bottom plate member and the side members are arranged as independent components with uniform specifications, are fixed and molded in advance, and are assembled to form a standard hexagonal cabin when in use. The sealing plate can be used for packaging after the frame of the whole cabin is built, or can be fixed on corresponding components in advance, so that the components are disassembled and packaged in the transportation process, and are assembled to form a temporary cabin when in use.
The packaging plate adopts double-layer arrangement, so that the sealing plate and the shielding layer can be separated from each other and respectively transported, the more wear-resistant sealing plate and each component are stored together, and the non-wear-resistant shielding layer can be transported by adopting more reasonable protective measures. In addition, the lead-free radiation-resistant rubber layer with proper thickness can be selected according to the shielding requirements of different positions of the cabin by adopting the shielding layers which are independently arranged. And the weight of the lead-free radiation-resistant rubber is far lower than that of the lead plate, so that the transportation burden is greatly reduced, and the environment cannot be polluted.
The CT equipment is independently transported, and is placed and debugged after the cabin is assembled, so that the problem that the CT equipment is directly fixed in the square cabin to be transported to be influenced by factors such as resonance, deformation and the like in the prior art can be solved. The scheme adopts a hexagonal cabin structure, and corrects the distribution condition of the radiation field during the working of the scanning cabin given by the national standard, so that the working position of the medical staff is arranged at the place with the minimum irradiation amount, and the protection degree to the staff is improved.
Drawings
FIG. 1 is a schematic cross-sectional view of a chamber according to an embodiment of the present invention;
FIG. 2 is a schematic view of the two chambers of one embodiment of the present invention after they are in communication;
FIG. 3 is a schematic view of a cabin layout according to an embodiment of the present invention;
FIG. 4 is a schematic view of a radiation protection shield design;
FIG. 5 is a graph of the transmission of secondary radiation in a lead material;
FIG. 6 is a prior art CT radiation dose field distribution diagram;
fig. 7 is a flowchart of a process for modifying national radiation field distribution data according to an embodiment of the present invention.
Detailed Description
The detailed structure and implementation process of the present solution are described in detail below with reference to specific embodiments and the accompanying drawings.
As shown in fig. 1, in an embodiment of the present invention, an assembled honeycomb type X-ray diagnosis CT apparatus cabin is disclosed, which comprises a plurality of independent hexagonal three-dimensional cabins 100, and two or more cabins 100 can be communicated with each other through side edges to form a working room with a more reasonable layout.
Each compartment 100 comprises a top member 1, a bottom member 2, side members 3 and a closure plate (not shown).
The roof member 1 is a frame structure and serves as a roof of the cabin 100, and comprises a symmetrical hexagonal plane frame formed by connecting six top rods 11, and six inclined rods 12 are led out upwards at the connecting angles of the six top rods 11, so that a vertical angle of a three-dimensional hexagonal pyramid is formed.
The bottom member 3 is a hexagonal planar frame corresponding to the planar frame of the top member 1 in size and shape, i.e. serves as the floor of the cabin 100, and includes bottom rods 31 forming the side edges, bottom rib rods are correspondingly connected to the connecting corners of the six bottom rods 31, respectively, and each bottom rib rod forms a junction at the center, and the bottom rib rods also play a role in increasing the strength of the bottom member 3.
The side member 2 is a rectangular plane frame which is a plane frame to which the top member 1 and the bottom member 3 are respectively connected, i.e., a wall which is a cabin 100, and includes main bars 21 connected to both ends of the corresponding top bar 11 and bottom bar 31, respectively, and a lattice-shaped fence 22 connected between the adjacent main bars 21.
The closing plate is used as a wall plate for sealing each surface of the cabin 100 and comprises a sealing plate for closing the top member 1 and the side members 2, a shielding layer made of lead-free radiation-proof rubber, and a shock absorption structure layer for closing the bottom member 3.
In the present embodiment, the top member 1, the bottom plate 3, and the side members 2 are each an independent component of uniform specification, and are each a structure that is fixed and molded, and one standard hexagonal chamber 100 can be formed by assembly in use. The sealing plate can be packaged after the frame of the whole cabin 100 is built, or can be fixed on the top member 1, the bottom plate member 3 and the side members 2 in advance, so that all the components are stacked in the transportation process respectively, and can be directly assembled to form the cabin 100 when in use.
Because the bottom member 3 is adopted, the requirement on the terrain is not high, and simultaneously, the stability after the cabin 100 is placed can be further improved through the combination of a plurality of cabins, so that the applicability to different terrains is greatly improved.
The packaging plate adopts double-layer arrangement, so that the sealing plate and the shielding layer can be separated from each other and respectively transported, the more wear-resistant sealing plate and each component are stored together, and the non-wear-resistant shielding layer can be transported by adopting more reasonable protective measures. In addition, the lead-free radiation-resistant rubber layer with a suitable thickness can be selected according to the shielding requirements of different positions of the cabin 100 by adopting the independently arranged shielding layers. And the weight of the lead-free radiation-resistant rubber is far lower than that of a lead plate (the specific weight of lead is 11.3 g/cm)3) The weight of (2) is only equal to 1/2-3, so that the transportation load is greatly reduced, and the environment is not polluted.
The top member 1, the bottom plate 3 and the side members 2 are assembled by using hinge parts to facilitate assembly and disassembly, and the specific hinge parts can be any structures for realizing frame connection in the prior art, such as connecting plates and bolts for connecting adjacent frames together; or after the adjacent frames are connected by the fasteners, the frames are fixed by bolts.
The CT equipment is independently transported, and is placed and debugged after the cabin 100 is assembled, so that the problem that the CT equipment is directly fixed in the square cabin and is influenced by factors such as transportation shock and deformation in the prior art can be solved. A particular CT apparatus generally includes a scan room for X-ray scanning of a patient, a control room for controlling the motion of the scan room, and a preparation room for analyzing films taken during the scanning process. When the scanning cabin is placed, the placing positions of the three in the cabin 100 can be determined according to the distribution situation of the radiation field of the scanning cabin in working according to the national standard due to the adoption of the hexagonal cabin 100 structure. Because the existing national standard is a radiation field determined according to the shape of the shelter and the actual form of the radiation field is not considered, the radiation field needs to be recalculated and corrected when being applied, so that the positions of the scanning chamber, the control chamber and the preparation chamber are more reasonably arranged according to the hexagonal structure.
In one embodiment of the present invention, connecting rods respectively connecting opposite connecting corners are installed in the plane of the planar frame of the top member 1, each connecting rod forms a cross point at the center of the planar frame, and one diagonal brace 13 is respectively connected between the middle of each diagonal brace 12 and the cross point. The connecting rods and the diagonal braces 13 can improve the strength of the top member 1, increase the adaptability to the field environment, and facilitate the installation of accessory parts, such as ventilation pipes, on the top member 1.
To reduce the weight of the entire cabin 100 while ensuring the strength of the members, the top member 1 and the side members 2 can be made of aluminum alloy sections, while the bottom member 3 is made of higher strength angle steel.
The closing plate of the closing side member 2 can be gypsum board or aluminum alloy plate, and when the gypsum board is adopted, the thickness is 220-270 mm, and the density is 0.705g/cm3. A shielding layer made of lead-free radiation-proof rubber is directly attached to one side of the gypsum board in the cabin 100; the closing plate for closing the top member 1 can be made of L25x aluminum alloy plate, and the lead-free radiation-proof rubber on the top member 1 can be arranged on the plane frame of the top member.
The shock-absorbing structure layer can protect the CT equipment and reduce the vibration in the cabin 100, and generally comprises a rigid shock-absorbing flat plate and a lead rubber protective layer, wherein the rigid shock-absorbing flat plate is laid on the surface of the angle steel, the lead rubber protective layer is laid on the shock-absorbing flat plate, and a shock-absorbing support is arranged at the bottom of the angle steel. The shock-absorbing bracket can adjust the inclination of the whole cabin 100 through the adjusting bolt. The entire cabin 100 can be formed into a completely closed radiation-proof chamber by the lead-free radiation-proof rubber shields on the top member 1, the side members 2 and the bottom member 3.
The lead-free radiation-proof rubber used for the shielding layer can be prepared by taking one or more of compounds such as tungsten, bismuth, gadolinium and the like as aggregate and taking nitrile rubber or silicon rubber as filler, the specific lead equivalent is about 0.3-0.5 mmPb/mm, the thickness of the lead-free radiation-proof rubber is generally 2-5 mm according to shielding requirements, and the density of the lead-free radiation-proof rubber is 4.73-5.01 g/cm3。
As shown in FIG. 2, the single side of the chamber 100 of this embodiment has a length of at least 4.5m and a height of 2.7m, and forms an internal area of about 2 × 2.6 × 4.5.52≈105.3m2Wherein the equipment/preparation chamber area is about 27m2Control room is about 14m2The net area of the CT scanning room is about 64m2. Meets the requirements of medical X-ray diagnosis radiation protection GBZ130-2013, and the area of a CT diagnosis machine room is not less than 40m2The length of a single side is not less than 4.5m2The requirements of (2). The circled numbers in the figure represent points of interest.
As shown in fig. 3, in terms of indoor layout, the main functional areas include: a control room, a preparation room (a film reading room), a scanning room, a device room and the like which are connected; one way to optimize the placement of the various devices within the compartment 100 is given below.
1. The control room is located in the front of the chamber 100 and includes the preparation room together, disposed at a lower radiation dose level to the side of the scanning chamber axis. The control room is generally provided with air conditioners (air exchange is realized by utilizing a protective air duct), a control host, a display system, a working chair, a duplex film viewing lamp, a film box, a diagnosis report printer and other equipment facilities.
2. The scanning room is arranged in the middle of the whole cabin and is provided with equipment facilities such as a CT frame (scanning cabin), a dehumidifier (low-temperature control module), a medical film printer and the like.
3. The equipment room (including heating ventilation) provides functional requirements for operation of the cabin 100, heating, ventilation, etc. Respectively adopting 2 split air conditioners and 2 vehicle-mounted fuel oil fan heaters for guarantee, wherein an air outlet is positioned at the top of a machine room structure, and a return air inlet is positioned at the lower part of an indoor unit; the air outlets of the warm air blower are positioned at the left side and the right side of the front wall plate of the scanning outdoor compartment 100, and the air return inlet duct is positioned at the bottom of the front wall plate of the scanning indoor compartment 100; the lower parts of the partition walls of the scanning room and the control room are provided with ventilating nozzles for air return of the heating and ventilation system, and the ventilating nozzles have a protection function and are communicated by utilizing arc-shaped multi-fold air channels.
4. The ceiling of the cabin 100 is provided with an air conditioning duct, a lighting lamp strip, an ultraviolet germicidal lamp and the like. The switchgears and light switches are located at the rear end of the cabin 100. The upper and lower end plates of the cabin 100 are provided with annular ventilation wall boxes, and the top of the cabin 100 is provided with an annular air convection device (exhaust fan) to ensure air circulation.
As shown in fig. 4, in terms of radiation protection, since the CT apparatus employs a collimated X-ray fan beam intercepted by the patient and the detector array, and usually works in the range of 80 to 140kVp (120kV is a common working condition), the radiation sources in the CT scanning room can be generally classified into 2 types, one type is called primary radiation, which refers to radiation directly acting on the human body without being shielded by various types of shields around the radiation source; another type, called secondary radiation, includes scattered radiation, stray radiation, etc., is a major source of radiation burden in the CT room.
The range of the pitch factor value commonly used in various CT examinations is about 0.5-1.75, and specific parameters can be specially selected according to the needs of special examinations. The pitch is selected, among other things, primarily with respect to scan time, scan range and image quality. The larger the pitch, the shorter the scanning time for the same layer thickness and the same scanning range. However, the pitch is large, the amount of photons per unit volume is reduced, the density resolution is reduced, and the quality of the transverse image is also reduced. On the contrary, the pitch is smaller than 1, which means that the helical scanning overlaps, the density resolution is improved, but the scanning time is increased under the same scanning distance, and the correction of the pitch is considered in the shielding design. The predicted machine room workload under field emergency operation is listed in table 1.
TABLE 1 CT Room design workload
In one embodiment of the present invention, because the hexagonal chamber 100 is adopted, the situation of the radiation source needs to be re-analyzed according to the chamber shape, and the placement position of the scanning chamber (radiation source) is determined accordingly. However, the current national standard only provides standards for the arrangement of radiation sources in square or rectangular cabins, and the radiation sources cannot be directly applied to hexagonal structures.
The dose constraint value in the radiation protection design is set according to the radiation dose which is regulated in the national standard and can be accepted by professionals and the public in order to reasonably control the entrance of CT diagnosis sites, the annual effective dose of radiation workers is not higher than 5mSv/a, the annual effective dose of the public is not higher than 1mSv/a, and then the shielding design target value P is derived as follows: control zone 0.1 mSv/week; the uncontrolled zone was 0.02 mSv/week. The embodiment readjusts the setting position of the scanning bin according to the national standard requirement and by combining the cabin characteristics of the scheme.
As shown in fig. 7, the processing steps of the distribution and correction of the radiation field during the operation of the scanning chamber according to the national standard are as follows:
the focus here includes each side and top of the two compartments 100 after combination.
Step 200, respectively calculating the shielding thickness value of each concerned point by utilizing a CT dose index workload method and a CT dose length product workload method, carrying out reference comparison, then taking the position of a middle balance point, and placing a scanning bin in a mode of being vertical to the connecting surface of two cabins;
1. wherein the CT dose index (CTDI)100) The calculation process of the workload method is as follows:
TABLE 2 diagnostic reference levels for typical adult patient X-ray CT examination
CTDI100Is the dose index, defined as the integral of the dose profile curve along the standard cross-sectional central axis from-50 mm to +50mm, divided by the product of the nominal layer thickness and the number of slices N, mGy, at a single axial scan; CTDI100The values of (a) refer to the diagnostic reference levels of a typical adult patient X-ray CT examination in table 3, and the values represent the upper limit of the diagnostic dose in the CT examination and meet the regulations of the national standard X-ray computed tomography radioprotection requirements GBZ 165-2012. For CT system products meeting the national quality control testing standards, the diagnostic reference level is for CTDI100A conservative estimate of (c).
Calculating the CT dose index (CTDI) using the following formula100) Relationship to weighted CT dose index:
wherein, CTDIWTo weight CT dose index, CTDI100，centerCTDI centered on the mold body100Value, CTDI100，peripheryIs the mold body periphery CTDI100The unit of the value, three is: mGy;
calculating the radiation transmittance B at the focus point outside the shielding body:
wherein, P is a mask design target value, unit: mSv/week; d is the distance from the focus of interest outside the shielding body to the scanning center, and the unit is: m; t is a residence factor of the shielding personnel outside the body, and the value is shown in Table 3;
is the air kerma of scattered radiation during CT examination at a scanning center of 1m, unit: mGy/human; n is the number of diagnosed patients, unit: a human;
TABLE 3 personal residence factor for different locations and environmental conditions
| Environmental conditions | Human retention factor |
| |
1 |
| Adjacent chamber and film measuring and reading chamber of |
1 |
| Reception room, nurse table and |
1 |
| Shop, housing, child game room and |
1 |
| Patient examination and treatment room and |
1/2 |
| Corridor, field environment, |
1/5 |
| Toilet and |
1/10 |
| Stairs, outdoor seat area and |
1/20 |
| Unattended stall, parking lot and |
1/20 |
The B values are found to correspond to the equivalent lead thickness according to the CT secondary radiation transmission curve shown in fig. 5. The results of the calculations are shown in Table 4.
TABLE 4 CTDI100Workload method for calculating shielding thickness result
And finally, obtaining the corresponding shielding thickness values of different focus points.
The calculation process of the CT dose-length product DLP workload method is as follows:
the DLP workload method reported by reference to NCRP No.147 estimates the shield thickness of the machine room, and the weekly dose control P value adopted by the shield design is the same as the national standard requirement.
Then, the air kerma scattered radiation share of the CT is calculated by the following formula, and the DLP value is determined according to the national standard:
wherein the content of the first and second substances,
is the kinetic energy of the air kerma from scattered radiation generated under the condition of head scanning at the scanning center of 1m, unit: mGy/human;
is the kinetic energy of the air kerma from the scattered radiation generated under the condition of scanning the body at the scanning center 1m, unit: mGy/human; kappa is the proportionality constant, and CTDI is measured at a depth of 1cm below the surface of the phantom100When the scattering fraction, cm, obtained at a layer thickness of 10mm and standard reference conditions of 120kV is specified-1。
For a standard head phantom (phi 16cm), kappahead＝9×10-5cm-1(ii) a Mold body (phi is 32cm) kappabody＝3×10-4cm-1. NCRP No.147 reports several reference level values for the recommended different body part examination procedures, see tables 5 and 6, respectively.
TABLE 5 Diagnostic Reference Levels (DRL) for CT examination of adult patients from different studies
Table 6 default values for each inspection program DLP
In practice there are 2 cases where contrast agent is used and not, and there may be repeated examinations of the same region. The repeated examination accounts for about 40% of the total examination, and DLP multiplied by 1.4 is taken as a correction value in the calculation process and is set as a CT examination correction factor. The calculation results are shown in table 7.
Calculation of B value of transmittance see equation 3, parameter and "CT dose index 100 (CTDI)100) The calculated shielding thickness by the workload method is the same, and the value B in figure 5 is looked up to obtain the corresponding equivalent lead shielding thickness.
TABLE 7 calculation of shield thickness by DLP workload method
Before the CT system is put into practical use, the manufacturer will provide standard specific scanning conditions to measure the isodose distribution curve of the scattered radiation field, as shown in fig. 6. It can be seen that the ray protection plates on the machine frame and the side surfaces of the machine frame have shielding and attenuation effects on X-rays generated by the tube balls.
The scattered radiation level in the CT scanning room has anisotropy, the radiation dose level in the direction parallel to the machine frame is far smaller than the axial direction of the patient treatment table, and the distribution is in a 8-shaped or butterfly-wing shape (derived from GBZ/T180-2006). In the above calculation, the existing rectangular shelter can only be placed obliquely to avoid the severely irradiated region, and if the rectangular shelter is placed linearly, the observation region needs a larger distance no matter the CT dose index (CTDI) is adopted100) Either the workload method or the CT dose-length product (DLP) workload method, the dose estimation is based on an unattenuated point-source model. In consideration of the actual shielding attenuation effect of the gantry, the actual radiation dose level of the critical position parallel to the gantry is corrected to be 20% of the point source model according to the typical radiation field distribution and the isodose line level, and the result of correction calculation by the DLP workload method is shown in table 8.
TABLE 8 dose level correction and mask thickness estimation of parallel gantry key positions
According to the actual radiation field isodose line distribution and the radiation level corrected at the key position parallel to the frame, the result normalized to the lead equivalent is obtained by calculation, the lead equivalent of the thickness of each shielding body is about 0.89 mm-1.41 mm by combining the result analysis of other positions, the relative deviation of the result at the same position obtained by the 2 methods is less than +/-5%, and the result is more reliable. The lead equivalent results are all less than 2.5mm, and the lead equivalent results are equivalent to lead equivalent or other materials of 2mm shielded by common workload according to radiation shielding specification GBZ/T180-2006 of medical X-ray CT machine room; the evaluation standard of the lead equivalent or other material equivalent with larger workload of 2.5mm conforms, and meanwhile, the evaluation standard can also meet the condition that the air specific release energy rate is less than or equal to 2.5 mu Gy/h at the position of 0.3m on the outer surface of a machine room and when the residence factor T is more than or equal to 1/4; when the residence factor is less than or equal to 1/4, the air specific release kinetic energy rate is less than or equal to 7.5 mu Gy/h, and the shielding and protection design of the cabin meets the requirements of national occupational health standards.
The shield used in the cabin design consists essentially of 3 materials, the outer layers are an aluminum alloy frame and a gypsum board with a thickness of about 250mm, wherein the gypsum board has a mass density of 0.705g/cm3The 250mm gypsum board is about 1mm lead equivalent when irradiated by 120keV X-ray secondary radiation in a CT scanning room. The inner layer is X-ray lead-free protective rubber with the mass density of 4.73-5.01 g/cm3The thickness is about 3-5 mm (the lead-free protective rubber product takes functional particles such as tungsten, bismuth and gadolinium compounds as aggregate and nitrile rubber or NBR as filler), and for 120keV secondary radiation, the lead-free ray protective rubber with the thickness of 1mm is equivalent to 0.5mm lead equivalent. The protective requirements of a conservative estimated 2.5mm CT scanning room can be met by adopting a 250mm gypsum board (outer layer) +3mm lead-free protective rubber (inner layer).
The shelter similar to the container shape mainly adopts less than 4 rows of CT inspection systems at present, can complete the scanning of most parts such as the head, the neck, the chest, the abdomen, the limbs and the like, but can not complete the high-resolution inspection requirement of organs such as arteries, angiocarpy and the like, and in addition, the scanning processing time of a single frame of image is about 5 seconds due to less than 4 rows of CT, while the processing time of a CT system of 16 rows and above is less than 1 second. Therefore, the hexagonal chamber 100 according to the present embodiment can adopt a 16-row CT system and the above configuration, thereby effectively improving the image resolution and greatly improving the inspection accuracy and efficiency (higher than the inspection requirement of the field hospital for 200 persons every day).
By adopting the honeycomb structure, the adjacent machine rooms share the protective wall body, so that the distributed arrangement is facilitated, the unified control is realized, the efficiency is high, the occupied area is small, and the protective materials and the medical resources are saved. The cabin component and the CT system are separately arranged, the requirements of long-distance transportation and shock absorption and the use under severe environmental conditions are met, and the workload of system maintenance, leveling and calibration is small. The top of the cabin is provided with the air exhaust device, the air flow field is smooth, the structure is simple, and the ventilation and warm-keeping effects are good. In addition, the cyclone circulation design can meet the preposition requirement of a special negative pressure system.
The following description will explain the design effects of the present invention by using specific examples.
1、CDTI100Weighted CT dose index workload design validation examples.
The weighted CT dose index values of the head and the body under the common scanning conditions of 5 types of CT equipment with 22 types including Germany Siemens (Siemens), Netherlands Philips (Philips) and American General Electric (GE) are actually measured on site, and the default setting of the tube voltage of an actual scanning program called in the acquisition process is 120 kV. The head die body is an acrylic resin human tissue equivalent die body with the diameter of 16cm and the length of 20cm, and the die body is an acrylic resin human tissue equivalent die body with the diameter of 32cm and the length of 20 cm.
The measurement results are as follows:
the CT system of Germany Siemens company is: 1) model SOMATOM Definition Flash, dual source dual detector System, 70% to 90% patient dose reduction, CTDI, compared to conventional Multi-slice spiral CT (64-row spiral CT)100Mean head 38.44mGy, body 12.47mGy measured; 2) model SOMATOM Emotion16, 16-row Dual Source, CTDI100Mean head 24.8mGy, body 19.37mGy were measured; 3) model number SOMATOM sensing 64, row 64, HeartDetail scanning, CTDI100Mean head 38.46mGy, body 18.88mGy measured; 4) model SOMATOM CR, 16 Row Total body Scan, CTDI100Mean head 33.25mGy, body 19.26mGy measured; 5) SOMATOM PERSPECTIVE, 64-line/128-layer Whole body Scan, CTDI100Mean head 37.14mGy, body 13.06mGy were measured.
CT system by Philips (Philips): 1) model Brilliance CT big Bore, Large pore CT, CTDI100Mean head 26.8mGy, body 11.25mGy measured; 2) model Brilliance64, line 64, coronary and cardiac scrutiny, CTDI100Mean head 27.55mGy, body 13.33mGy measured; 3) model Access, Low dose CT System, CTDI100Mean head 33.26mGy, body 16.18mGy were measured.
GE company CT system, usa: 1) model Light Speed, 4-row spiral CT, CTDI100Mean head 37.60mGy, body 19.86mGy measured; 2) model Light Speed VCT, 64-row spiral CT, CTDI100Mean head 54.70mGy, body 14.33mGy measured; 3) model Pro Speed (obsolete model), single row spiral CT; 4) optima, dynamic 500 Row, CTDI100Mean head 25.88mGy, body 12.37mGy measured; 5) BRIVISCT 325, X-ray auto-calibration, double row CT, CTDI100Mean head 38.1mGy, body 14.19mGy were measured. Except for the Light Speed VCT head model 54.7mGy, other models meet the requirements of the diagnosis reference level for limiting the head to be less than 50mGy, the body to be less than 35mGy (lumbar) or 25mGy (belly),
japan toshiba CT system: TSX-031A, Alexion TSX-032A, Activion16TSX-031A, Aquilon ONE TSX-301A, Alexion TSX-031B, Aquilon ONE TSX-301A, etc., CTDI100The mean head 46.8mGy and body 19.92mGy were measured, all of which meet the diagnostic reference level with the exception of the model Aquillion ONE TSX-301A head 61.37mGy, which limits the head to less than 50mGy, body to less than 35mGy (lumbar) or 25mGy (abdominal).
CT system of domestic shenyang dongsu corporation: CT-C2800, NeuViz64, CT-C3000, etc., CTDI100The mean head 33.81mGy and body 16.83mGy measurements all met the diagnostic reference level limit for heads less than 50mGy and bodies less than 35mGy (lumbar) or 25mGy (abdominal).
As can be seen from the field measurement results, except for the extreme individual model numbers, the design benchmark adopted by the invention is smaller than the CTDI recommended by the following standard100Meets the requirements of 'X-ray computed tomography radiation protection requirements' GBZ165-2012, and indicates that suitable radiation protection shielding can be provided.
2. Verification of instances Using the DLP dose-Length product workload method
3 medical X-ray Computed Tomography (CT) devices of different models (Siemens SOMATOM sensing, Philips Brillance, general electric BrightSpeed) are selected, DLP values in 157 scanning programs in recent patient dose reports of 4 hospitals are collected, and collected data classification statistical results are shown in a table 9.
TABLE 9 DLP data Collection statistics Table for patients
Note that: the total DLP of the patient body scan is an example of coronary angiography examination in the survey data, and the total DLP value of the patient is 2654mGy · cm in total after 5 scan procedures.
The CT scattered radiation air kerma is calculated according to the formula (4) and the formula (5).
The radiation transmittance B for a given shield thickness is calculated using the following equation:
α: 2.246mm when the tube voltage is 120kVp-1；β：5.73mm-1；γ：0.547mm-1(ii) a Data are quoted from NCRP No. 147.
The radiation dose of the shielding external focus under the protection of 120kVp and 2.5mm lead equivalent is as follows:
D(x)＝W×B
the daily work load W of the scattered radiation is calculated according to a formula
As can be seen from table 10, under the condition that the shielding thickness of each shielding body is 2.5mmPb equivalent, the predicted radiation dose per week calculated under the CT normal working load condition and the limit working load condition is less than 0.1 mSv/week of the shielding design target control area; the non-control area is 0.02 mSv/week, and meets the design requirement of radiation protection.
TABLE 10 expected radiation dose for point of interest outside the shield under existing shielding protocols
Thus, it should be appreciated by those skilled in the art that while a number of exemplary embodiments of the invention have been illustrated and described in detail herein, many other variations or modifications consistent with the principles of the invention may be directly determined or derived from the disclosure of the present invention without departing from the spirit and scope of the invention. Accordingly, the scope of the invention should be understood and interpreted to cover all such other variations or modifications.
Claims (10)
1. The utility model provides an assembled honeycomb X ray diagnosis CT equipment cabin which characterized in that, includes hexagonal three-dimensional cabin, and two cabins realize intercommunication each other through the side, and every cabin includes:
the top component is of a frame structure and comprises a symmetrical hexagonal plane frame formed by connecting six top rods and a top angle formed by inclined rods led out upwards at each connecting angle;
the bottom component is a hexagonal plane frame corresponding to the plane frame of the top component in size and shape, and comprises bottom rods forming side edges and bottom rib rods respectively connected with the connecting corners of the bottom rods;
the side component is a rectangular plane frame which is respectively connected with the top component plane frame and the bottom component plane frame, and comprises main rods which are respectively connected with two ends of the corresponding top rod and the corresponding bottom rod, and fences which are connected with the two main rods;
the sealing plate comprises a sealing plate for sealing the top component and the side component, a shielding layer made of lead-free radiation-proof rubber, and a shock absorption structure layer for sealing the bottom component;
the CT equipment comprises a scanning cabin, a control room and a preparation room, and the arrangement positions of the scanning cabin, the control room and the preparation room in the cabin are determined according to the radiation field distribution given by the national standard when the scanning cabin works and correction.
2. The CT equipment room of claim 1,
connecting rods respectively connected with the opposite connecting angles are installed in the plane frame surface of the top component, each connecting rod forms a cross point at the center of the plane frame, and an inclined stay bar is respectively connected between the middle part of each inclined bar and the cross point.
3. The CT equipment room of claim 1,
the top member, the bottom member and the side members are connected to each other by hinges.
4. The CT equipment room of claim 1,
the top member and the side members are made of aluminum alloy sections, the closing plate is a gypsum board or an aluminum alloy plate, when the gypsum board is adopted, the thickness of the closing plate is 220-270 mm, and the density of the closing plate is 0.705g/cm3。
5. The CT equipment room of claim 1,
the bottom component is made of angle steel, the shock absorption structure layer comprises a shock absorption flat plate paved on the surface of the angle steel, a lead core rubber protection layer paved on the shock absorption flat plate, and a shock absorption support for adjusting and debugging is installed at the bottom of the angle steel.
6. The CT equipment room of claim 1,
the lead-free radiation-proof rubber of the shielding layer is prepared by taking one or more of tungsten, bismuth and gadolinium as aggregate and taking nitrile rubber or silicon rubber as filler, and is 2-5 mm in thickness, 0.3-0.5 mmPb/mm in lead equivalent and 4.73-5.01 g/cm in density3。
7. The CT equipment room of claim 1,
the length of the single side of the cabin is at least 4.5m, and the height of the cabin is 2.7-3.3 m.
8. The CT equipment room of claim 1,
the processing steps of distributing and correcting the radiation field during the working of the scanning bin according to the national standard are as follows:
step 100, dividing parts of two connected cabins affected by radiation into different focus points by taking an X-ray source in a protection plate of a scanning cabin as a scanning center;
step 200, respectively calculating the shielding thickness value of each concerned point by utilizing a CT dose index workload method and a CT dose length product workload method, carrying out reference comparison, then taking the position of a middle balance point, and placing a scanning bin in a mode of being vertical to the connecting surface of two cabins;
step 300, determining that a radiation field formed after the X-ray source is attenuated by the protection plate is a butterfly wing type which takes the protection plate as a contraction section and expands towards two ends, firstly correcting the radiation value of a corresponding focus point which is influenced by the protection plate to reduce the radiation amount, and finally placing the control chamber and the preparation chamber at the position with the lowest radiation level.
9. The CT device compartment of claim 8,
the CT dose index (CTDI)100) The calculation process of the workload method is as follows:
calculating the CT dose index (CTDI) using the following formula100) Relationship to weighted CT dose index:
wherein, CTDIWTo weight CT dose index, CTDI100，centerCTDI centered on the mold body100Value, CTDI100，peripheryIs the mold body periphery CTDI100The unit of the value, three is: mGy;
calculating the radiation transmittance B at the focus point outside the shielding body:
wherein, P is a mask design target value, unit: mSv/week; d is the distance from the focus of interest outside the shielding body to the scanning center, and the unit is: m; t is a residence factor of personnel outside the shielding body,
is the air kerma of scattered radiation during CT examination at a scanning center of 1m, unit: mGy/human; n is the number of diagnosed patients, unit: a human;
and finally, obtaining the corresponding shielding thickness values of different focus points.
10. The CT device compartment of claim 8,
the CT dose-length product (DLP) workload method is calculated as follows:
firstly, estimating the estimated shielding thickness of each concern point according to the radiation dose control standard specified in the national standard;
then, the air kerma scattered radiation share of the CT is calculated by the following formula, and the DLP value is determined according to the national standard:
wherein the content of the first and second substances,
is the kinetic energy of the air kerma from scattered radiation generated under the condition of head scanning at the scanning center of 1m, unit: mGy/human;
is the kinetic energy of the air kerma from the scattered radiation generated under the condition of scanning the body at the scanning center 1m, unit: mGy/human; kappa is a proportionality constant;
and correcting the DLP value according to the influence caused by using and not using the contrast agent to obtain the corresponding shielding thickness values of different focus points.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010608407.8A CN111691715A (en) | 2020-06-29 | 2020-06-29 | Assembled honeycomb type X-ray diagnosis CT equipment cabin |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010608407.8A CN111691715A (en) | 2020-06-29 | 2020-06-29 | Assembled honeycomb type X-ray diagnosis CT equipment cabin |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN111691715A true CN111691715A (en) | 2020-09-22 |
Family
ID=72484389
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202010608407.8A Withdrawn CN111691715A (en) | 2020-06-29 | 2020-06-29 | Assembled honeycomb type X-ray diagnosis CT equipment cabin |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN111691715A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114099193A (en) * | 2021-10-18 | 2022-03-01 | 湖南西雅德辐射防护科技有限公司 | Lead-free CT (computed tomography) shelter structure |
-
2020
- 2020-06-29 CN CN202010608407.8A patent/CN111691715A/en not_active Withdrawn
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114099193A (en) * | 2021-10-18 | 2022-03-01 | 湖南西雅德辐射防护科技有限公司 | Lead-free CT (computed tomography) shelter structure |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US11723612B2 (en) | Hybrid flat panel detector for cone beam CT systems | |
| Frederiksen et al. | Effective dose and risk assessment from film tomography used for dental implant diagnostics | |
| DeMarco et al. | A Monte Carlo based method to estimate radiation dose from multidetector CT (MDCT): cylindrical and anthropomorphic phantoms | |
| Groh et al. | A performance comparison of flat‐panel imager‐based MV and kV cone‐beam CT | |
| Kalki et al. | Myocardial perfusion imaging with a combined x-ray CT and SPECT system | |
| Lazos et al. | Monte Carlo evaluation of scatter mitigation strategies in cone‐beam CT | |
| Gislason-Lee | Patient X-ray exposure and ALARA in the neonatal intensive care unit: global patterns | |
| CN103300875B (en) | Radiation grading protection system of medical shelter for field environment | |
| CN111691715A (en) | Assembled honeycomb type X-ray diagnosis CT equipment cabin | |
| Chapple et al. | Energy imparted to neonates during X-ray examinations in a special care baby unit | |
| Chiang et al. | Scattered radiation doses absorbed by technicians at different distances from X-ray exposure: Experiments on prosthesis | |
| Prieto et al. | Ultra-low dose whole-body CT for attenuation correction in a dual tracer PET/CT protocol for multiple myeloma | |
| National Committee on Radiation Protection (US) | Structural shielding design for medical x-ray imaging facilities | |
| KR102124343B1 (en) | Apparatus for Reducing Scatter Radiation in Mobile X-ray Equipment | |
| Schultz et al. | Calculation of dose conversion factors for posterior–anterior chest radiography of adults with a relatively high-energy X-ray spectrum | |
| Hanson et al. | Radiation Shielding for Clinics and Small Hospitals with a WHIS-RAD 2013 | |
| Boissonnat et al. | Performance of automatic exposure control on dose and image quality: comparison between slot‐scanning and flat‐panel digital radiography systems | |
| Ilori et al. | Entrance Skin Dose (Radiation) Measurement and Evaluation (for all age groups) at the State Specialist Hospital, Okitipupa, Nigeria | |
| US20230225685A1 (en) | Scanner Utilizing Beam Computed Tomography And Antiscatter Grid | |
| Prieto-Azcárate et al. | Ultra-low dose whole-body CT for attenuation correction in a dual tracer PET/CT protocol for multiple myeloma | |
| Liu et al. | Monte Carlo simulation of bowtie filter scatter on a wide-cone low-dose CT system | |
| Malone | Five Step Shielding Calculations | |
| Metzger et al. | A Monte Carlo shielding model for PET/CT clinics | |
| Schultz et al. | Effective doses for different techniques used for PA chest radiography | |
| CN207538733U (en) | The radiation-retarding door of radiation-proof effect can be improved |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| WW01 | Invention patent application withdrawn after publication | ||
| WW01 | Invention patent application withdrawn after publication |
Application publication date: 20200922 |