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Variations in depth-dose data between open and wedge fields for 4-MV X-rays.

W Sewchand·F M Khan·J Williamson
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Abstract

Central-axis depth-dose data for 4-MV x rays, including tissue-maximum ratios, were measured for wedge fields. Comparison with corresponding open-field data revealed differences in magnitude which increased with depth, field size, and wedge thickness. However, phantom scatter correction factors for the wedge fields differed less than 1% from corresponding open-field factors. The differences in central-axis per cent depth doses between the two types of fields indicate beam hardening by the wedge filter. This study also implies that the derivation of tissue-maximum ratios from central-axis per cent depth is as valid for wedge as for open fields.

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HumansRadiotherapy DosageRadiotherapy, High-EnergyX-RaysJournal ArticleResearch Support, U.S. Gov't, P.H.S.

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W Sewchand, F M Khan, J Williamson. 1978. Variations in depth-dose data between open and wedge fields for 4-MV X-rays.. https://doi.org/10.1148/127.3.789

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