Duties of radiology technologist in radiation protection
The purpose of preparing this article is to provide information and new methods to protect yourself, the patient and others in the radiology department from radiation. Radiation protection programs are based on a simple ALARA philosophy , which means high quality testing with low risk.
Three important principles in radiation protection:
Reduction of patient radiation is at the disposal of technology:
• Select conditions: Use high KV
• Foley or screens: Using high speed foleys
• Radiographic film: The use of high-sensitivity films reduces the absorption dose of the patient, while Foley and the film must be compatible.
• Cassette: By choosing cassettes with carbon fiber top instead of cassettes with aluminum top, the amount of radiation dose is reduced by 40%.
• Grid or network: Choosing a grade with the right ratio has an effect on the amount of radiation dose, and in cases such as radiographs of children and thin organs, grade should not be used.
• Using high FFD and applying Airgap technique
• Using aids to keep the patient steady instead of accompanying the patient during radiation, the person holding the patient should be male and elderly as much as possible and should be placed at an angle of 90 degrees to the primary radiation, while he should use a lead cover.
View status: Using the PA view of the skull instead of the AP reduces the radiation of the eye lens by 95%. In scoliosis patients with requests for back and lumbar vertebrae, using the PA view instead of the AP view reduces breast radiation by 99%.
• In lung radiography using photocell devices, if the radiation center is set on the T6 vertebra instead of the T4 vertebra, it will reduce the radiation dose and increase the quality of the image.
• Reducing and limiting the size of the radiation field to the desired level, reducing the size of the radiation field in waist imaging from 8 x 10 cm to 6 x 6 cm, reduces the absorbed dose of the patient by 50%.
• The correctness of the requests in terms of individual characteristics, the desired area, specifying the member in terms of left and right should be carefully checked.
• The presence of two technologists at the same time by the patient’s side is useful in terms of positioning and choosing the conditions for some radiographs and reduces the repetition of radiographs.
• Quality control of radiology devices is effective in radiation protection of patients, by periodically checking the performance of the devices, calibration, maintenance and maintenance of the processor, the absorption dose of the patients can be reduced.
• Notes of technical conditions on portable stereotypes, especially in graphs that require special conditions and may cause repetition of the stereotype, reduce the patient’s dose.
• The technologist’s familiarity with film interpretation ensures high quality images and protects the patient against radiation.
• Investigating the factors involved in repeated graphs: In Europe and America, the amount of repeated graphs is around 4 to 15%, and in these cases, the most repetitions include back, lumbar and chest vertebrae.
• Use of protectors: Shields are devices that are used to protect oneself, the patient, and the patient’s companions. These shields must be standard and certified and must be used on all people.
Types of guards:
- Lead cover: Bone marrow protection is 75 to 80%.
- Protection of gonads: In the range of less than 5 cm distance of the gonads from the initial radius of the gonad protection ray, it must be used unless it interferes with the quality of the image.
- Thyroid protection: By using protectors, 90% of the absorbed dose of this area is reduced.
- Lead glasses: It reduces the absorption dose of the eyes by 98%.
Regarding the protection of the pregnant patient, three important points should be kept in mind:
- When was the person’s last menstrual period?
- The rule of ten days should be followed.
- In case of doubt, take a pregnancy test.
Protection of children from radiation: In children, due to the low cooperation and high radiation sensitivity of the gonads, thymus and thyroid, the amount of repetition should be minimized in them, and the following should be considered in the radiography of children:
1- The use of means of proof and justification of the child’s parents
2- Use of gonadal protection (mandatory)
3- Using grade with low ratio if necessary
4- Use of fast foley
5- Familiarity with child psychology
6- Limiting exposure to one view instead of using comparative views
7- Using high KV and low time.
Protection in portable radiographs: the amount of scatter radiation at a distance of one meter is higher in portable radiographycompared to fluoroscopy. In portable radiography, making contact with the patient and leaving the place by the patient’s companions reduces the dose of radiation that reaches them.
Radiation protection in fluoroscopy and angiography:
1- Not using fluoroscopy to center the radiation
2- Use of interrupted radiation technique (fractionation) instead of continuous radiation
3- Ensuring the correct operation of the device, especially its timer
4- Observance of proper distance
5- Not using grid in children
6- Installation of curtain, protection and lead hanger