Thesis (MTech (Radiography))--Peninsula Technikon, 2004 / The radiation risks associated with children are higher than the risk for adults.
Children have growing organs and they have a longer life expectancy than that of
adults. As a consequence the effects of damage from radiation could be greater than
in adults. Children who receive radiation damage may pass genetic damage onto
future generations.
This study was carried out to investigate the optimal effective x-ray dose young
children need to receive who have radiographic examination to the chest at Tygerberg
Hospital, South Africa. Chest radiographs are documented as being the most common
radiographic examination done on children. The age groups of children participating
in this study were 0-1 year, 1-5 years and 5-10 years. A total of 67 children were
involved and the absorbed doses for 134 views of the anterior-posteria (AP) chest and
lateral chest were measured.
Entrance surface dose (ESD) values were determined, and measured mean ESD
(mGy) and the ESD range was reported for each age group. This was done by
attaching thermolurninescent dosirneters (TLD pellets) to the patients skin at the
entrance point of the x-ray beam. The results were compared to similar studies done
in Ireland and Nigeria From the ESD values obtained the absorbed doses ofthe eyes,
heart, liver, thyroid and genitals could be calculated by using the "Childdose"
programme ofthe NRPB.
The ESD dose levels for South Africa compare favourably with Ireland. However the
Nigerian values differed greatly from those of Ireland and South Africa It was very
encouraging to note the comparative results achieved at Tygerberg Hospital especially
due to the fact that this was the first time such study had been conducted in the
Tygerberg Hospital Radiology Department. The results also compare favourable with
that achieved by a group working in the United Kingdom. This group does similar
surveys every five years as part of their radiation protection programme. The results
were also in line with the UNSCEAR document of2000.
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This study could serve as a valuable source of reference to radiographers and
radiologists when performing paediatric radiology especially as the radiation absorbed
dose could be used as a baseline to create awareness of size of dose received, and to
limit deleterious radiation doses to patients and to prevent unnecessary exposures.
A second significant outcome of the study was the effect that added filters had on the
x-ray beam generated. Experiments were done in which the filtration filters were
added sequentially. It was found that if the filtration was increased to 2mmAl the dose
to the patient decreased by more than 20%. At 50 and 60 kV the density of the x-ray
image on film only increased by 2%. From these results it may be concluded that an
increase in filtration thickness used for paediatric chest x-rays should be giVIng
reduced dose readings and assisting with radiation protection ofthe patient.
| Identifer | oai:union.ndltd.org:netd.ac.za/oai:union.ndltd.org:cput/oai:localhost:20.500.11838/1546 |
| Date | January 2004 |
| Creators | Swart, Gillian |
| Publisher | Peninsula Technikon |
| Source Sets | South African National ETD Portal |
| Language | English |
| Detected Language | English |
| Type | Thesis |
| Rights | http://creativecommons.org/licenses/by-nc-sa/3.0/za/ |
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