What are purposes and scope of medical mammography equipment inspection in Vietnam?
What are purposes and scope of medical mammography equipment inspection in Vietnam? What is process of inspection of mammography equipment for medical use in Vietnam?
Please advise according to regulations.
What are purposes and scope of medical mammography equipment inspection in Vietnam?
In Section I, Appendix III.10 issued together with Circular 08/2022/TT-BKHCN (effective from July 22, 2022) stipulating purposes and scope of medical mammography equipment inspection as follows:
1. Purpose
This procedure prescribes validation for medical mammography equipment.
2. Scope and subjects of application
This procedure applies to organizations and individuals participating in the service of testing mammography equipment for medical use; state management agencies and other relevant organizations and individuals.
What is process of inspection of mammography equipment for medical use in Vietnam?
According to Section I.3, Appendix III.10 issued together with Circular 08/2022/TT-BKHCN (effective from July 22, 2022) inspecting mammography X-ray equipment for medical use with contents process as follows:
3.1. diagram
1. Prepare equipment, tools and supplies |
=> |
2.1. Visual inspection |
=> |
3. Inspection result report |
|
|
| |
|
| |
|
|
2.2. Check compression device |
|
4. Inspection certificate |
|
|
| |
|
|
|
|
2.3. Check rated voltage |
|
|
|
|
| |
|
|
|
|
2.4. Check exit dose |
|
|
|
|
| |
|
|
|
|
2.5. Check beam localization |
|
|
|
|
| |
|
|
|
|
2.6. Primary beam filter |
|
|
|
|
| |
|
|
|
|
2.7. Check image quality |
|
|
3.2. Explain
Step 1: Prepare equipment, tools and supplies.
Step 2.1: Check the appearance
- Check X-ray equipment information.
- Check the control panel.
- Inspect mechanical parts and structures.
- Check the beam warning signal.
Step 2.2: Check the compression device
- Check the accuracy of breast thickness indicator/indicator ruler.
- Check the accuracy of the compression force.
- Check the maximum compression force.
Step 2.3: Check the number of peak voltage
- Check the accuracy of peak voltage
+ Place the multimeter or peak voltage measuring device on the support plate and at the center of the radiation field.
+ Focus the beam so that the radiation field covers the entire radiation sensitive area of the measuring device.
+ Select manual operation mode , set the beam emission constant within the commonly used range or as recommended by the instrument manufacturer. Perform emission corresponding to each voltage change in the operating range of the X-ray device.
- Check repeatability of peak voltage
+ Fix the multimeter or peak voltage measuring device on the support plate and at the center of the radiation field.
+ Focus the beam so that the radiation field covers the entire radiation sensitive area of the measuring device.
+ Select manual operation mode, emission constant and frequently used target/filter pair.
+ Carry out at least 03 times of beam generation with the same peak voltage value and keep the same set value of the emission constant.
Step 2.4: Check exit dose
- Check output dose repeatability
- Fix the multimeter or dosimeter 45 mm above the support plate.
- Focus the beam so that the radiation field covers the entire surface of the radiation sensitive area of the measuring device.
- Record the distance from the focal point to the measuring device.
- Select manual operation mode, commonly used beer/filter pair.
- Perform at least 03 emission times corresponding to the same voltage parameters and commonly used emission constants.
- In the case of X-ray equipment with another target/filter pair, repeat the above steps corresponding to the maximum peak voltage value normally used.
- Check output dose linearity
+ Fix the multimeter or dosimeter above the 45 mm . support plate
+ Focus the beam so that the radiation field covers the entire surface of the radiation sensitive area of the measuring device.
+ Record the distance from the focal point to the measuring device.
+ Select manual operation mode, target/filter pair and commonly used peak voltage.
+ Select 03 values of radiation constant in the working range of X-ray equipment.
+ Perform ray emission corresponding to each value of emission constant.
+ In case the X-ray equipment has another target/filter pair, use this target/filter pair and repeat the above steps with the maximum peak voltage value normally used.
Step 2.5: Check beam condenser
- Stick 04 pieces of fluorescent tape on the 4 sides of the support plate and stick 01 piece of fluorescent tape on the center of the radiation field on the support plate.
- Place the metal sheet on the edge of the tape near the chest so that the outer edge of the metal sheet is 5 mm from the support plate. Place the 3 metal plates on the remaining 3 pieces of tape so that the outer edge of the metal plate is 2% of the distance from the focus to the imager from the edge of the support plate.
- Perform ray generation corresponding to the peak voltage and voltage constant commonly used.
- Record the test parameters in the inspection record.
- Move the compression plate to a position 40 - 60 mm from the support plate; Stick 01 X-ray ruler under the edge of the compression plate (near the chest) so that the zero line coincides with the edge of the compression plate.
- Turn on the light field and place 04 X-ray rulers with the zero line coincident with the 4 edges of the light field (note: the X-ray ruler is not placed on the adhesive tape).
- Perform ray emission corresponding to the set of parameters of peak voltage, voltage constant, commonly used target/filter pair.
Step 2.6: Primary Beam Filter
- Select manual operation mode, target/filter pair and commonly used voltage.
- Place the multimeter or dosimeter in the center, 45 mm from the support plate and 40 mm from the edge of the platform (near the chest).
- Focus the beam so that the radiation field covers the entire surface of the radiation sensitive area of the measuring device.
- In case the measuring device has a direct display of the HVL value: beam and record the HVL value on the measuring device.
- In case the measuring device does not display the value of HVL
+ Perform beam emission when the aluminum plate has not been placed on the compression plate.
+ Place a 0.3 mm thick aluminum plate (or 0.4 mm depending on the target/filter pair and peak voltage) on the compression plate. Perform irradiation and record the dose value on the measuring device. This measured dose value must be greater than 1/2 of the dose measured when the aluminum plate is not placed. If this value is not satisfied, use a thinner aluminum plate.
+ Add 0.1 mm thick aluminum plate. Perform irradiation and record the dose value on the measuring device. This measured dose value must be less than 1/2 of the dose measured when the aluminum plate is not placed. If this value is not satisfied, add aluminum plate until this measured dose value is less than 1/2 of the dose measured without aluminum plate.
+ Remove all aluminum filters, perform irradiation and record the dose value on the measuring device.
- Repeat the above steps with the target/filter pair and other peak voltage commonly used in the facility.
Step 2.7: Check image quality
- Place the contrast threshold test phantom on the mounting plate according to the phantom manufacturer's instructions.
- Choose to set parameters of peak voltage, emission constant, compression force and commonly used target/filter pair.
- Perform beam emission.
- For digital and digitized X-ray equipment: the contrast threshold is determined based on the phantom image and the phantom manufacturer's instructions.
- For X-ray equipment using film: after processing the film, the contrast threshold is determined based on the image of the phantom on the film and the instructions of the phantom manufacturer.
Step 3: Report the inspection results
- The inspection results must be made into an inspection record with all the contents according to Form 1. The inspection record is issued together with QCVN 21:2019/BKHCN.
- The inspection minutes must be approved and signed and stamped (if any) by the members:
+ The representative of the facility using the X-ray equipment or the person authorized by the establishment;
+ Persons assigned by the establishment using X-ray equipment to participate and witness the inspection;
+ The person performing the test.
- Based on the data of the test results in the inspection report, the person performing the verification must calculate and evaluate the working characteristics of the X-ray equipment according to the instructions and make a report. audit assessment according to Form 2. Report on inspection results issued together with QCVN 21:2019/BKHCN.
Step 4: Certificate of inspection
- The certificate of inspection is only issued to the X-ray equipment after it has been tested and concluded to meet the acceptance requirements.
- When the inspected X-ray equipment meets the acceptance requirements, the inspection organization must issue an inspection certificate within 15 working days from the date of approval of the inspection report at the establishment according to the Form 3. Certificate of inspection issued together with QCVN 21:2019/BKHCN.
Best Regards!









