title: [Examination of formula for enhanced dynamic wedge factors in symmetric and asymmetric fields].
abstract: 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.
authors.affiliation: Department of Radiation Oncology, The Cancer Institute Hospital of Japanese Foundation for Cancer Research.
authors.forename: Tomoharu
authors.initials: T
authors.lastname: Sato
authors.forename: Nobuhide
authors.initials: N
authors.lastname: Tachibana
authors.forename: Takashi
authors.initials: T
authors.lastname: Hanada
authors.forename: Nozomi
authors.initials: N
authors.lastname: Kitamura
authors.forename: Yuuko
authors.initials: Y
authors.lastname: Ootomo
authors.forename: Masaru
authors.initials: M
authors.lastname: Nakajima
authors.forename: Shinichi
authors.initials: S
authors.lastname: Yoshino
authors.forename: Satoko
authors.initials: S
authors.lastname: Ishikawa
authors.forename: Teruo
authors.initials: T
authors.lastname: Ito
authors.forename: Takeo
authors.initials: T
authors.lastname: Hashimoto
authors.forename: Masaharu
authors.initials: M
authors.lastname: Kimura
authors.forename: Minoru
authors.initials: M
authors.lastname: Yoshioka
mesh_terms: D002138:Calibration; D006801:Humans; D011874:Radiometry / Q000379:methods*; D011879:Radiotherapy Dosage; D011881:Radiotherapy, Computer-Assisted / Q000379:methods*