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PubMed · 3685100

Scatter dose for wedged fields.

L H Brown·R L Siddon·B E Bjärngard
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Abstract

The behaviour of scatter dose in 4 and 8 MV wedged x-ray beams has been studied by calculating scatter-to-primary dose ratios (SPR) and comparing these with SPR for non-wedged beams. On the central axis the SPR for wedged and non-wedged beams differ only by a few per cent, a difference which increases slightly with wedge angle and field size. In other points within the field the differences are larger but generally less than 3% of the total dose on the central axis at the same depth. The product rule for points that do not lie in a principal plane is valid within the same limits as for non-wedged beams.

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Cobalt RadioisotopesRadiationRadiotherapyScattering, RadiationX-RaysJournal ArticleResearch Support, U.S. Gov't, P.H.S.

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L H Brown, R L Siddon, B E Bjärngard. 1987. Scatter dose for wedged fields.. https://doi.org/10.1088/0031-9155%2F32%2F10%2F010

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