Abstract:
:Using a plane-parallel advanced Markus ionization chamber and a stack of water-equivalent solid phantom blocks, percentage surface and build-up doses of Elekta 6 MV flattening filter (FF) and flattening-filter-free (FFF) beams were measured as a function of the phantom depth for field sizes ranging from 2 × 2 to 10 × 10 cm2 . It was found that the dose difference between the FF and the FFF beams was relatively small. The maximum dose difference between the FF and the FFF beams was 4.4% at a depth of 1 mm for a field size of 2 × 2 cm2 . The dose difference was gradually decreased while the field size was increased up to 10 × 10 cm2 . The measured data were also compared to published Varian FF and FFF data, suggesting that the percentage surface and build-up doses as well as the percentage dose difference between FF and FFF beams by our Elekta linac were smaller than those by the Varian linac.
journal_name
J Appl Clin Med Physjournal_title
Journal of applied clinical medical physicsauthors
Imae T,Takenaka S,Watanabe Y,Aoki A,Matsuda K,Sasaki K,Saegusa S,Nawa K,Nakagawa K,Abe Odoi
10.1002/acm2.13094subject
Has Abstractpub_date
2020-12-01 00:00:00pages
334-339issue
12issn
1526-9914journal_volume
21pub_type
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journal_title:Journal of applied clinical medical physics
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