Mahdavi Seied Rabie, Geraily Ghazale, Mostaar Ahmad, Zia Arman, Esmaili Golbarg, Farahani Somayeh
Department of Medical Physics and Medical Engineering, Faculty of Medicine, Iran University of Medical Sciences, Tehran, Iran.
Department of Medical Physics and Medical Engineering, Faculty of Medicine, Tehran University of Medical Sciences, Tehran, Iran.
J Cancer Res Ther. 2017 Apr-Jun;13(2):313-317. doi: 10.4103/0973-1482.183562.
Physical wedges (PWs) are widely used in radiotherapy to obtain tilted isodose curves, but they alter beam quality. Dynamic wedges (DWs) using moving collimator overcome this problem, but measuring their beam data is not simple. The main aim of this study is to obtain all dosimetric parameters of DWs produced by Varian 2100CD with Monte Carlo simulation and compare them to those from PWs.
To simulate 6 MV photon beams equipped with PW and DW, BEAMnrc code was used. All dosimetric data were obtained with EDR2 films and two-dimensional diode array detector.
Good agreement between simulated and measured dosimetric data for PW and DW fields was obtained. Our results showed that percentage depth dose and beam profiles at nonwedged direction for DWs are the same as open fields and can be used to each other.
From Monte Carlo simulations, it can be concluded that DWs in spite of PW do not have effect on beam quality and are good options for treatment planning system which cannot consider hardening effect produced by PWs. Furthermore, BEAMnrc is a powerful code to acquire all date required by DWs.
物理楔形板（PWs）在放射治疗中广泛用于获得倾斜的等剂量曲线，但会改变射束质量。使用移动准直器的动态楔形板（DWs）克服了这一问题，但测量其射束数据并不简单。本研究的主要目的是通过蒙特卡罗模拟获得瓦里安2100CD产生的DWs的所有剂量学参数，并将其与PWs的参数进行比较。
使用BEAMnrc代码模拟配备PW和DW的6MV光子束。所有剂量学数据均通过EDR2胶片和二维二极管阵列探测器获得。
PW和DW野的模拟剂量学数据与测量数据之间取得了良好的一致性。我们的结果表明，DWs在非楔形方向的百分深度剂量和射束剖面与开放野相同，可相互使用。
从蒙特卡罗模拟可以得出结论，DWs与PW不同，对射束质量没有影响，对于无法考虑PW产生的硬化效应的治疗计划系统来说是很好的选择。此外，BEAMnrc是获取DWs所需所有数据的强大代码。
