Learning objective of this study was to demonstrate the scattering of radiation in radiographic imaging.
Four Philips DoseAware personal dosimeters and an imaging phantom were used for testing.
The test room was a typical x-ray examination room located in the school of health and social care.
Scattering was measured in six different situations including distance from the primary beam,
effect of increasing and decreasing of milliampere-second (mAs),
angle to the primary beam,
direction from the primary beam (side,
overhead or below),
tube voltage and field...
Basic test setting was constructed on the base of the chest radiography of a patient who is lying on his back.
Following parameters were used on all the other exposesexcept mAs test,
tube voltage test and the field size test.
Tube voltage: 125 kV
Milliampere-second: 2 mAs
FFD (focus-to-film distance): 110 cm
FSD (focus-to-skin distance): 83 cm
Field size: 24cm x 27cm
One of the dosimeters was always in the primary beam as a control.
Others were positioned depending on the variable we were testing....
Findings and procedure details
The first test settingis shown in figure 1.
and the test results in table 1.
Findings in the distance test were equal to Newton’s Inverse Square Law meaning that the radiation intensity is inversely proportional to the distance from the source (e.g.
Thompson 2006; Carlton Adler 2006)
In the milliampere-second test was found out that the dose of the scattered radiation is directly proportional to the mAs as well as increasing tube voltage increases the scattering radiation and vice versa.
Studying the angle ofscattering radiation...
The results were in line with the known theories of the radiation physics.
The study was a useful way to demonstrate and learn about scattering in radiation in a practical way.
Results can be used when teaching radiographers about radiation protection and imaging outside x-ray department and when patient has to be held during examination.
It is also important that radiographer is aware of the scattering radiation in order to protect her / him self when working on the controlled area.
Kenny P &johnston R 2006.Oxford University Press.
Carlton R & Adler A 2006 Principles of Radiographic Imaging.
An Art and a science.