In view of this, the current study analyzes and compares dosimetric characteristics of 6MV flattening filter free and flattened beams of three beam-matched linear accelerators (linacs) from three...

Percent depth dose (%DD) distributions give the dose, relative to maximum dose, as a function of depth. There are several key features of a %DD chart that should be noted. Skin Sparing. MV photons do not reach maximum dose at the surface/skin but build-up to a maximum dose.

Abstract—In this study the measurements for PDDs were measured using a linear accelerator (Electa synergy) with 6 MV, 10 MV and 12MV photon energies and electron energies of 6MeV, 9MeV and 12MeV at reference field size under constant condition.

2020年5月18日 · The table below shows central axis PDD data for a 6 MV photon beam. A patient is prescribed 8 Gy in one fraction to d max on the central axis using a 10 × 10 cm field size. The field size is then changed to 11 × 16 cm. Assuming the MU are corrected to give the same dose at the prescription point, what will be the difference in the dose ...

2017年7月1日 · This work aims to compare and evaluate the dosimetric properties of 6 MV flattening (FF) and flattening filter free (FFF) photon beams which generated from a Varian 2100 medical accelerator. These properties include percentage depth dose, dose rate, beam profile, out-of-field, energy spectra, scatter factor, and surface dose.

2023年7月28日 · In this study we referred to 6MV flattened (FF) photon beam and 6MV flattening filter free (FFF) photon beam, with respective dose rates of 500MU/min and 1200MU/min. For Elekta accelerators, beam matched linacs have identical technical characteristics and multileaf collimator features.

We performed a comprehensive set of surface and buildup dose measurements with a thin window parallel‐plate (PP) chamber to examine effects of field size (FS), source‐to‐skin distance (SSD), and attenuating media.

2022年7月14日 · pdd的中文名是百分深度剂量，通俗来说，描述了射线能量沉积与模体深度之间的关系，比如在体表处沉积的能量是多少，在某一深度处沉积的能量是多少。

Percept depth dose (PDD) for 6MV photon beam measured by the PSLD sheet and PTW Semiflex ionization chamber. Dose distributions for photon beam were measured using a Photo-Stimulated...

本研究工作用实验测量的北京医疗器械研究所生产的6MV电子直线加速器X射线谱作为输入数据,计算加速器水箱测量的基本数据PDD和OAR曲线并和实验测量的相应曲线进行比较.这里的X射线能谱是经过MonteCarlo程序EGS4的模拟计算结果验证过的.从比较的结果看,无论能谱 ...