[Examination of formula for enhanced dynamic wedge factors in symmetric and asymmetric fields].
We proposed a formula for the enhanced dynamic wedge (EDW) factor in the half-field (HF) that combined the formula proposed by Liu et al. in 1998 and their formula in 2003. When the EDW was used for irradiation to the tangent line of the HF breast, the values calculated by our formula and the measured values were consistent within 0.5%. We showed that our proposed formula was useful, easy to use, and more accurate than the conventional formula. The purpose of this study was to examine the available range of the wedge factor of symmetrical and asymmetric EDW calculated by our formula. As a result of the examination, the values calculated by our formula and the measured values were consistent within 2% except for highly asymmetric EDW. We created a spreadsheet to calculate the wedge factor easily and accurately. We will examine the reason why the calculated and measured values were greater than 2%, and improve our formula so that it can be used in a wider range.
Sato
Tomoharu
T
Department of Radiation Oncology, The Cancer Institute Hospital of Japanese Foundation for Cancer Research.
Tachibana
Nobuhide
N
Hanada
Takashi
T
Kitamura
Nozomi
N
Ootomo
Yuuko
Y
Nakajima
Masaru
M
Yoshino
Shinichi
S
Ishikawa
Satoko
S
Ito
Teruo
T
Hashimoto
Takeo
T
Kimura
Masaharu
M
Yoshioka
Minoru
M
D002138:Calibration; D006801:Humans; D011874:Radiometry / Q000379:methods*; D011879:Radiotherapy Dosage; D011881:Radiotherapy, Computer-Assisted / Q000379:methods*