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YY/T 0706-2017

Chinese Standard: 'YY/T 0706-2017'
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BASIC DATA
Standard ID YY/T 0706-2017 (YY/T0706-2017)
Description (Translated English) Particular specifications for mammographic X-ray equipment
Sector / Industry Medical Device & Pharmaceutical Industry Standard (Recommended)
Classification of Chinese Standard C43
Classification of International Standard 11.040.50
Word Count Estimation 22,295
Date of Issue 2017-03-28
Date of Implementation 2018-04-01
Older Standard (superseded by this standard) YY/T 0706-2008
Drafting Organization Liaoning Province, Medical Device Testing Institute, Shenyang Neusoft Medical Systems Co., Ltd., Shenzhen St. Connaught Medical Equipment Co., Ltd.
Administrative Organization National Medical Appliance Standardization Technical Committee Medical X-ray equipment and appliances Standardization Technical Committee (SAC/TC 10/SC 1)
Regulation (derived from) China Food & Drug Administration Announcement 2017 No. 38
Proposing organization China Food and Drug Administration
Issuing agency(ies) State Food and Drug Administration

YY/T 0706-2017
Particular specifications for mammographic X-ray equipment
ICS 11.040.50
C43
People's Republic of China Pharmaceutical Industry Standard
Replacing YY/T 0706-2008
Technical conditions for mammography
Released on.2017-03-28
2018-04-01 implementation
State Food and Drug Administration issued
Content
Foreword I
1 range 1
2 Normative references 1
3 Terms and Definitions 1
4 Classification and composition 2
5 Requirements 2
6 Test method 6
Appendix A (informative) Low contrast test phantom 13
Appendix B (informative) Breast imaging phantom 15
Appendix C (Normative Appendix) Mammary mean dose gland calculation 17
Foreword
This standard was drafted in accordance with the rules given in GB/T 1.1-2009.
This standard replaces YY/T 0706-2008 "Technical Conditions for Mammography X-ray Machines".
Compared with YY/T 0706-2008, the main technical changes of this standard are as follows.
--- Modified the "scope" (see Chapter 1);
---Modified "normative references" (see Chapter 2);
---Modified "terms and definitions" (see Chapter 3);
--- Modified "Classification and Composition" to increase the content of digital mammography machines (see Chapter 4);
--- Revised "specified by product standards" to "specified by the manufacturer" (see Chapter 5, Chapter 6);
--- Modified "Load factor control and display" (see 5.3);
--- Modified the "Automatic Exposure Control (AEC) System" (see 5.4.1);
--- Modified "artifacts" (see 5.4.2);
---Modified the "Imaging Performance" section (see 5.4.3, 5.4.4, 5.4.5, 5.4.6, 5.4.7, 5.4.8);
---Modified "mechanical movement" (see 5.5.1);
---Modified "compression device" (see 5.5.2);
--- Modified the "pressure plate" (see 5.5.3);
---Modified "braking force" (see 5.5.4);
---Modified the "mobile performance of mobile mammography machine" (see 5.5.7);
--- Modified "bearing weight" (see 5.5.8);
---Modified "noise" (see 5.5.9);
--- Added "angle indication value" (see 5.5.6);
---Modified "high-voltage cable plugs and sockets" (see 5.7);
--- Removed "Continuous loading 3min";
---Modified part of "Load factor control and display" (see 6.3);
--- Modified the "Automatic Exposure Control (AEC) System" (see 6.4.1);
--- Modified "artifacts" (see 6.4.2);
--- Removed "total filtration", "material decay rate between the upper surface of the breast tray and the image receptor plane", "active anti-scatter filter
"Dilution of wire shadow", "high contrast resolution";
--- Added "afterimage", "anti-scatter filter grid", "spatial resolution low contrast resolution", "mammary gland dose", "digital
Image uniformity" (see 6.4.3, 6.4.4, 6.4.5, 6.4.6, 6.4.7, 6.4.8);
---Modified "mechanical device performance" (see 6.5.1, 6.5.2, 6.5.3, 6.5.4, 6.5.5, 6.5.6, 6.5.7, 6.5.8, 6.5.9);
---Modified "high-voltage cable plugs, sockets", "environmental requirements", "safety and electromagnetic compatibility requirements" (see 6.7, 6.9, 6.10);
--- Added Appendix A, Appendix B and Appendix C.
Please note that some of the contents of this document may involve patents. The issuing organization of this document is not responsible for identifying these patents.
This standard was proposed by the State Food and Drug Administration.
This standard is determined by the National Medical Electrical Equipment Standardization Technical Committee Medical X-ray Equipment and Appliance Standardization Subcommittee (SAC/
TC10/SC1) is in charge.
This standard was drafted. Liaoning Medical Device Inspection and Testing Institute, Shenyang Neusoft Medical System Co., Ltd., Shenzhen Shengnuo Medical Equipment
Limited company.
The main drafters of this standard. Shan Xu, Hou Yaofang, Liang Tiecheng, Ye Chengfu, Liu Jingbo.
This standard replaces YY/T 0706-2008.
The previous versions of the standards replaced by this standard are.
---YY/T 0706-2008.
Technical conditions for mammography
1 Scope
This standard specifies the terms and definitions, classification and composition, requirements and test methods of mammography machines (hereinafter referred to as mammography machines).
This standard applies to mammography machines.
This standard does not apply to biopsy devices, stereotactic devices and tomographic devices of mammography machines.
2 Normative references
The following documents are indispensable for the application of this document. For dated references, only dated versions apply to this article.
Pieces. For undated references, the latest edition (including all amendments) applies to this document.
GB 9706.1 Medical electrical equipment - Part 1. General requirements for safety
GB 9706.11 Medical electrical equipment - Part 2. Safety requirements for medical diagnostic X-ray source components and X-ray tube assemblies
GB 9706.12 Medical electrical equipment Part 1. Safety general requirements III. Parallel standard diagnostic X-ray equipment radiation protection
common enquiries
GB 9706.14 Medical electrical equipment - Part 2. Particular requirements for safety of X-ray equipment
GB 9706.15 Medical electrical equipment - Part 1-1 - Safety common requirements - Parallel standard. Medical electrical system safety requirements
GB 9706.24-2005 Medical electrical equipment - Part 2-45. Mammography equipment and mammography stereo positioning device
Safety specific requirements
GB/T 10149 medical X-ray equipment terminology and symbols
GB/T 17006.9 Evaluation and routine testing of medical imaging systems - Part 2-10. Stability test mammography
device
GB/T 19042.2-2005 Evaluation and routine testing of the medical imaging sector - Part 3-2. Mammography X-ray equipment
Performance acceptance test
YY 0076-1992 Technical conditions for coating classification of metal parts
YY/T 0106 General technical conditions for medical diagnostic X-ray machines
YY/T 0291 Environmental requirements and test methods for medical X-ray equipment
YY/T 0480 Diagnostic characteristics of X-ray imaging equipment and mammography anti-scatter grid
YY 0505 Medical Electrical Equipment - Part 1-2. Safety General Requirements Parallel Standards. Electromagnetic Compatibility Requirements and Testing
YY/T 1541 Mammography X-ray machine high voltage cable assembly and socket technical conditions
3 Terms and definitions
The following terms and definitions as defined in GB/T 10149 apply to this document.
3.1
Projection frame gantryforradiography
A device that supports components such as X-ray tube heads.
3.2
Compression device compressiondevice
A special device for compressing the breast on a mammary machine, including a compression plate, a patient support, and a device for controlling compression movement.
3.3
Compression plate compressionplates
A transparent plate on the mammary machine that is used to compress the patient's breast.
3.4
Average gland dose averageglandulardose; AGD
Using the prescribed calculation method, the average absorption of the breast gland tissue (excluding the skin) whose known composition is uniformly compressed is calculated.
dose.
3.5
Contrast noise ratio contrasttonoiseratio; CNR
A physical quantity that describes the ability of a system to distinguish between different contrast objects and the inherent noise of an image in a digital image.
3.6
Artifact artifact
A structure that is clearly visible on an image. It does not reflect the internal structure of the object, nor can it be explained by noise or system modulation transfer functions.
[GB/T 19042.2-2005, definition 3.3.1]
3.7
Afterimage erasurethoroughness
Part of the previous image that was generated in the subsequent image due to incomplete signal removal after the previous image signal was read
All.
3.8
Unprocessed image unprocessedimage
After pixel defect correction and field correction, the image is not post-image processed.
4 Classification and composition
4.1 Classification
4.1.1 According to the product structure, it can be divided into fixed and mobile mammography machines.
4.1.2 According to the image data output format, it can be divided into screen (analog) and digital mammography.
4.2 Composition
The mammography machine should have at least the following main components.
a) X-ray generating device;
b) the projection frame;
c) compression device;
d) image receiving device;
e) Breast image acquisition workstation (for digital mammography).
5 requirements
5.1 Working conditions
5.1.1 Environmental conditions
Unless otherwise specified, the working environment of the mammary machine should meet.
a) Ambient temperature. 10 ° C ~ 40 ° C;
b) Relative humidity. 30%~75%;
c) Atmospheric pressure. 700hPa~1060hPa.
5.1.2 Power conditions
The manufacturer shall state in the random document the power conditions used for the product, and the operating power conditions shall satisfy.
a) power supply voltage and number of phases. specified by the manufacturer, the network voltage fluctuations should not exceed ± 10% of the nominal value;
b) Power frequency. 50Hz ± 1Hz;
c) Power supply resistance. It should meet the requirements of 10.2.2 of GB 9706.24-2005;
d) Power supply capacity. specified by the manufacturer.
5.2 Electric power
5.2.1 Maximum output electric power
The mammography machine should specify the corresponding combination of X-ray tube voltage and X-ray tube current that results in the maximum output electrical power.
5.2.2 Nominal electric power
It should be specified in kilowatts (kW) that the X-ray generator can provide when the loading time is 0.1 s and the X-ray tube voltage is 30 kV.
The unit's maximum constant electrical power output is given as the nominal electrical power. If this value cannot be pre-selected, the X shot closest to 30kV can be used.
The line voltage value and the closest load time value, but not less than 0.1s.
The nominal electrical power should be given in combination with the X-ray tube voltage and X-ray tube current and load time.
5.3 Loading factor control and display
5.3.1 X-ray tube voltage
5.3.1.1 The mammography machine shall specify the voltage adjustment range and adjustment mode of the X-ray tube. The maximum X-ray tube voltage value shall not exceed 50kV.
5.3.1.2 The manufacturer shall specify the deviation of the voltage value of the X-ray tube, but at least it shall comply with 50.103.1a of GB 9706.24-2005.
Claim.
5.3.2 X-ray tube current
5.3.2.1 If the X-ray tube current display is provided, the mammography machine shall specify the X-ray tube current adjustment range and adjustment method.
5.3.2.2 The manufacturer shall specify the deviation of the X-ray tube current value, but at least it shall comply with the requirements of 50.103.2 of GB 9706.24-2005.
5.3.3 Loading time
5.3.3.1 If the loading time display is provided, the mammography machine shall specify the loading time adjustment range and adjustment method.
5.3.3.2 The manufacturer shall specify the deviation of the load time value, but at least it shall comply with the requirements of 50.103.3 of GB 9706.24-2005.
5.3.4 Current time product
5.3.4.1 If the current time product is displayed, the mammography machine shall specify the current time product adjustment range and adjustment mode.
5.3.4.2 The manufacturer shall specify the deviation of the current time product value, but at least it shall comply with the requirements of 50.103.4 of GB 9706.24-2005.
5.3.5 Anti-overload
The mammography machine should have anti-overload measures to ensure that the loading factor selection does not exceed the rated capacity of the X-ray tube. Should comply with the instruction manual
The combination of the maximum load factors given in .
5.3.6 Focus
5.3.6.1 The manufacturer shall specify the nominal value of the X-ray tube assembly.
5.3.6.2 When using the normal exposure mode, the nominal value of the X-ray tube assembly should not be greater than 0.4; when using the magnified photographic exposure mode, X-ray
The nominal value of the conduit assembly focus should not be greater than 0.2.
5.3.6.3 When multiple focus is provided, the preselected focus shall be displayed prior to exposure, except that the automatic exposure control (AEC) is used to adjust the focus.
5.3.6.4 If the focus is automatically selected, the focus of the actual exposure should be displayed after exposure.
5.3.7 Target surface material
5.3.7.1 The mammography machine shall specify the target surface material used for the X-ray tube.
5.3.7.2 When multiple targets are provided, in addition to using AEC to modulate the target, the preselected target should be displayed prior to exposure.
5.3.7.3 If the target is automatically selected, the actual exposed target should be displayed after exposure.
5.3.8 Additional filtration
5.3.8.1 The mammography machine shall specify the additional filtration used.
5.3.8.2 When multiple filtrations are provided, in addition to using AEC to adjust for additional filtration, a pre-selected additional filtration shall be displayed prior to exposure.
5.3.8.3 If additional filtering is automatically selected, additional filtering of the actual exposure should be displayed after exposure.
5.4 Imaging performance
5.4.1 Automatic Exposure Control (AEC) System
5.4.1.1 The mammography machine shall provide an automatic exposure control (AEC) system.
5.4.1.2 The implementation of the automatic exposure control function should be described in the random file.
5.4.1.3 The repeatability of the digital mammography automatic exposure control is measured by the deviation of the dose or milliampere second, and the deviation value should not be greater than
±5%.
5.4.1.4 The manufacturer shall specify the automatic exposure of the digital mammography machine to different thicknesses of polymethyl methacrylate (PMMA) phantoms.
The contrast-to-noise ratio (CNR) minimum of the response.
5.4.2 Artifacts
There should be no visible artifacts.
5.4.3 Afterimage
For digital mammography, the residual coefficient value should be less than 0.3.
5.4.4 Anti-scatter grid
5.4.4.1 The configuration of the anti-scatter grid should be given in the random file (if there is a grid or no gate, moving grid or static grid).
5.4.4.2 There shall be no visible visible shadows within the specified loading time and/or phantom thickness range.
5.4.4.3 When the maximum compressive force is applied to the dynamic grid, the movement of the grid shall not be affected.
5.4.4.4 In the magnification photography mode, the grid should be removed without being left in the radiation beam.
5.4.5 Spatial resolution
5.4.5.1 The spatial resolution of the screen type mammography machine should not be less than 12 lp/mm.
5.4.5.2 The spatial resolution of the digital mammography machine should not be less than 5 lp/mm.
5.4.6 Low contrast resolution
For digital mammography machines, manufacturers should specify low contrast resolution.
5.4.7 average glandular gland dose
5.4.7.1 The mammography should show the average glandular dose of the mammary gland per irradiation.
5.4.7.2 The digital mammography machine shall display the average gland dose for each captured image.
5.4.7.3 The average gland dose in the normal photography mode of the mammary gland should meet the limits in Table 1.
Table 1 Maximum average gland dose requirements for each thickness of PMMA material
PMMA thickness value/mm equivalent breast thickness value/mm maximum average gland dose value/mGy
20 21 1.0
40 45 2.0
70 90 6.5
5.4.8 Digital image uniformity
The maximum deviation of the gray value between the central area and the surrounding area specified by the image receptor shall not exceed ±10%.
5.5 Mechanical performance
5.5.1 Mechanical movement
5.5.1.1 The range of travel of the projection frame in the vertical direction shall be specified, and the deviation of the stroke range shall be less than ± 5%.
5.5.1.2 The angle of rotation of the projection frame and the deviation value shall be specified. The angular deviation value shall be less than ±2°.
5.5.1.3 The projection bracket shall be locked at any position on the full stroke.
5.5.1.4 Focus---The distance of the image receiving surface (FID) should not be less than 600mm.
5.5.1.5 When the power supply is interrupted, the mechanical movement is locked except for the compression plate.
5.5.2 Compression device
5.5.2.1 The pressure should be stable when under pressure, and the pressure value should not exceed 10% within at least 1 min.
5.5.2.2 Where applicable, the equipment is capable of displaying the applied force and its indication value deviation shall be less than ±20N.
5.5.3 Pressure plate
The compression plate shall comply with the relevant requirements of GB 9706.24-2005.
5.5.4 Braking force
The linear motion and the rotational motion part of the mechanical device should have a braking device (the suspension device requires the balancing without the need for braking).
Outside), its braking force should not be less than 100N.
5.5.5 Length indication value
The deviation between the indicated value of the length (excluding the compression thickness) and the actual value shall not be greater than ± 5% of the indicated value.
5.5.6 Angle indication value
The deviation of the indicated value of the angle from the actual value is specified by the manufacturer.
5.5.7 Mobile performance of mobile mammography
The human-moving mammography machine moves on a flat concrete floor, and the starting push (pull) force applied to the handlebar should not exceed 250N.
5.5.8 Load bearing
Devices that support adult patients (eg, pedals, chairs, beds) can work properly with 100kg of mass.
5.5.9 Noise
When the mammography machine is running under no-load conditions (non-load-bearing state), the noise generated should not exceed 70dB (A-weighted network) (not including 3s)
Non-persistent and aperiodic noise within).
5.6 Software Features
If applicable, the manufacturer shall specify the functionality of the operating software.
5.7 High voltage cable plug and socket
Unless otherwise specified, the requirements for type and basic dimensions, marking, and connection in YY/T 1541 shall be met.
5.8 Appearance
5.8.1 The shape of the mammary machine should be neat and beautiful, the surface should be smooth and smooth, the color should be uniform, and there should be no defects such as scars and cracks.
5.8.2 The main plating parts of the mammography machine shall comply with the requirements of Class 2 appearance in YY 0076-1992.
5.9 Environmental test
Unless otherwise specified, the product shall comply with the requirements of YY/T 0291. The initial, intermediate or final test item shall include at least 5.3.1 a),
5.3.2 a), 5.3.3 a), 5.3.4 a), 5.5.4 (when electrical braking) and 5.6 requirements.
5.10 Safety and Electromagnetic Compatibility Requirements
Should comply with GB 9706.1, GB 9706.11, GB 9706.12, GB 9706.14, GB 9706.15, GB 9706.24 and YY 0505
Claim.
6 Test methods
6.1 Test conditions
6.1.1 Environmental conditions
Should comply with the provisions of 5.1.1.
6.1.2 Power conditions
The test power supply conditions for the mammography machine are as follows.
a) The grid voltage and phase number shall comply with the manufacturer's specifications, and the grid voltage fluctuation shall not exceed ± 5% of the nominal value;
b) Power frequency. 50Hz ± 1Hz;
c) The power supply resistance shall comply with the provisions of 5.1.2c);
d) The power supply capacity shall comply with the provisions of 5.1.2d).
6.2 Electric power
6.2.1 Maximum output electric power
Loads are combined according to the loading factors that cause the maximum output power, and the presence or absence of abnormalities is observed.
6.2.2 Nominal electric power
The combination of X-ray tube voltage, X-ray tube current, and loading time leading to the nominal electric power was observed to observe whether there was any abnormality.
6.3 Loading factor control and display
6.3.1 X-ray tube voltage
6.3.1.1 X-ray tube voltage adjustment According to the X-ray tube voltage adjustment range and adjustment method specified in 5.3.1.1, observe the actual operation.
6.3.1.2 The deviation test of the X-ray tube voltage value shall be carried out in accordance with the provisions of 50.104.1 of GB 9706.24-2005.
6.3.2 X-ray tube current
6.3.2.1 X-ray tube current adjustment According to the X-ray tube current adjustment range and adjustment method specified in 5.3.2.1, observe the actual operation.
6.3.2.2 Deviation test of X-ray tube current value shall be carried out in accordance with the provisions of 50.104.2 of GB 9706.24-2005.
6.3.3 Loading time
6.3.3.1 Loading time adjustment According to the loading time adjustment range and adjustment method specified in 5.3.3.1, observe the actual operation.
6.3.3.2 Deviation test of loading time value shall be carried out in accordance with the provisions of 50.104.3 of GB 9706.24-2005.
6.3.4 Current time product
6.3.4.1 Current time product adjustment According to the current time product adjustment range and adjustment method specified in 5.3.4.1, observe the actual operation.
6.3.4.2 The deviation test of current time product shall be carried out in accordance with the provisions of 50.104.4 of GB 9706.24-2005.
6.3.5 Anti-overload
Adjust the parameters of the mammography machine to the maximum load factor combination value specified in the instruction manual, and then adjust any load factor to increase adjacently.
When the gear is added, the loading factor condition is no longer increased or is in an overload state. For mammography machines with continuous adjustment of X-ray tube voltage, anti-overload
When the operating voltage value of the device is higher than the X-ray tube voltage value specified in the instruction manual (but not exceeding 5kV), it should not be exposed and the alarm is displayed.
6.3.6 Focus
6.3.6.1 Check the random file check.
6.3.6.2 Actual operation, visual inspection.
6.3.6.3 Actual operation, visual inspection.
6.3.6.4 Actual operation, visual inspection.
6.3.7 Target surface material
6.3.7.1 Check the random file check.
6.3.7.2 Actual operation, visual inspection.
6.3.7.3 Actual operation, visual inspection.
6.3.8 Additional filtration
6.3.8.1 Check the random file check.
6.3.8.2 Actual operation, visual inspection.
6.3.8.3 Actual operation, visual inspection.
6.4 Imaging performance
6.4.1 Automatic exposure control (AEC) system
6.4.1.1 Actual operation, visual inspection.
6.4.1.2 Review random files.
6.4.1.3 Place a 40mm thick PMMA phantom on the patient support, with the phantom edge aligned with the chest wall side of the patient support; compression plate pressure
On the phantom; set the commonly used tube voltage and target/filtering for AEC exposure; repeat exposure 5 times to calculate the current time of each measurement
The maximum deviation of the product or dose value from the corresponding mean.
Note. Automatic exposure control should be provided in one possible combination, for example. with grid, without grid, magnified photography, non-magnified photography and various targets/filters
The combination is used to achieve its function; in addition, the probe for measuring the dose should avoid the sensor that affects the AEC.
6.4.1.4 Place 20mm, 40mm, 60mm thick PMMA phantoms on the patient support, phantom edge and patient support chest
The wall side is aligned, the compression plate is pressed on the phantom, AEC exposure is performed, and the exposure parameters such as tube voltage, current time product and target/filtering are recorded. Will be thick
An aluminum sheet having a degree of 0.20±0.01 mm (purity of not less than 99.9% and a size of 30 mm×30 mm) is placed on the upper surface of the PMMA phantom, so that
Manual exposure with the same exposure parameters as before (if not exactly the same, the closest exposure parameter is used). When getting each thickness
The unprocessed image of the exposure, respectively measuring the area of interest of the area of 400 mm2 in the area 2 shown in Fig. 1, the gray value of the aluminum image
Mean and standard deviation (mAl, σAl) and an area of interest of 400 mm2 in region 1, the mean and standard deviation of the gray value of the background image
(mBG, σBG), calculate the CNR value according to equation (1).
CNR=
mBG-mAl
σ2BG σ2Al
(1)
In the formula.
mAl--- is the average value of the gray value of the region 2;
σAl --- is the standard deviation of the gray value of the region 2;
mBG--- is the mean value of the gray value of the region 1;
σBG--- is the standard deviation of the grayscale value of the region 1.
Figure 1 Schematic diagram of CNR measurement
6.4.2 Artifacts
a) Screen type mammography machine is carried out according to the provisions of 5.10.2 of GB/T 19042.2-2005.
b) Digital mammography machine, placing a uniform filter plate in the radiation beam, using a 20mm thick PMMA phantom, and receiving at least from the image
200mm above the surface. Set the X-ray tube voltage to 28kV (or close to the set value of this value), perform AEC exposure, or apply
When the current time product is exposed, the image can be optimally visualized by contrast and brightness adjustment, and visually inspected.
6.4.3 Afterimage
Using a double exposure method, the first 40mm thick PMMA phantom was placed on the patient support to completely cover the chest wall end.
To the nipple end, but only cover half of the left and right, set the clinical common exposure conditions, manual exposure to capture images; the second will be 40mm thick
The PMMA phantom is placed in the same direction as the detector on the patient support, so that it completely covers the detector and is 0.1mm thick (purity not less than 99.9%,
The size of the 60mm × 60mm) aluminum plate is placed in the center of the PMMA phantom, using the same photographic conditions as the first time for exposure
Set the image, the exposure interval is about 1 min. Calculate the residual coefficient according to equation (2).
Residual coefficient =
AverageCounts(3)-AverageCounts(2)
AverageCounts(1)-AverageCounts(2)
(2)
In the formula.
AverageCounts(1)---the average gray value of 400mm2 in the area of interest 1;
AverageCounts(2)---the average gray value of 400mm2 in the area of interest 2;
AverageCounts(3)---the average gray value of 400mm2 in the area of interest 3.
Figure 2 Schematic diagram of the residual area
6.4.4 Anti-scatter grid
6.4.4.1 Review random files.
6.4.4.2 The mammography machine is equipped with a mammography head-tail position of the grid photography mode to capture the image state; the compression plate with the maximum applied force is installed.
And an image receptor adapted to the same; a 2 mm thick aluminum plate is fixed between the X-ray source assembly and the compression plate, and covers the entire X-ray
Line field; exposure is performed using AEC mode and the appropriate current time product is recorded. Remove the aluminum plate and it will have enough to cover the image receptor
A 20mm thick PMMA is placed in the center of the patient's stent, and the phantom edge is aligned with the patient's stent chest wall side, with the same mAs recorded.
Once again irradiated, the imaging should not have a visible grid shadow. Repeat measurements were taken at ±90° and 180°, respectively.
6.4.4.3 The mammography machine is equipped with a mast head-tail position to capture the image state; then the phantom is used (this object should be used in thickness)
It is a 20mm~50mm sandbag or a soft rubber block). Corresponding to the specifications of the smallest image receptor, the length and width of the phantom is 100mm~
120mm; corresponding to the size of the larger image receptor, the length and width of the phantom is 120mm~150mm, covering the patient support, pressing
Force the device to apply the maximum force. In this case, move the moving grid and expose it in AEC mode. The image cannot have visible grating shadow and no abnormality.
noise. Repeated measurements were taken at ±90° and 180° positions and in different image receptor modes.
6.4.4.4 Actual operation observation.
6.4.5 Spatial resolution
6.4.5.1 Place a 45mm thick PMMA phantom on the patient support, with the phantom edge aligned with the chest wall side of the patient support;
The discriminating card is placed horizontally and vertically with the X-ray tube assembly on the phantom; the exposure is given according to the parameters given by the manufacturer, if not specified,
Take AEC for exposure.
6.4.5.2 Place the 45mm thick PMMA phantom on the patient support, the phantom edge is aligned with the chest wall side of the patient support;
The force card is placed horizontally and vertically with the X-ray tube assembly on the phantom; the exposure is given according to the parameters given by the manufacturer. If not specified, select
AEC mode is used for exposure. The image can be adjusted for contrast and brightness for optimal viewing.
6.4.6 Low contrast resolution
The low contrast test card can be placed on the detector surface using the low contrast test card recommended in Appendix A, according to the manufacturer's specifications.
Set the loading factor, or use a 25kV X-ray tube.
Related standard:   YY/T 0292.1-2020  YY/T 0292.2-2020
Related PDF sample:   YY/T 0310-2015  YY/T 0741-2018
   
 
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