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Quality Assurance of Operation of Enhanced Dynamic Wedges in Linac  

Jeong, Dong-Hyeok (Department of Radiation Oncology, Wonkwang University Hospital)
Kim, Jhin-Kee (Department of Radiation Oncology, Jeonbuk National University Hospital)
Kang, Jeong-Ku (Department of Radiation Oncology, Presbyterian Medical Center)
Son, Kwang-Jae (Radioisotope Research Division, Korea Atomic Energy Research Institute)
Lee, Jeong-Ok (Department of Radiotechnology, Wonkwang Health Science College)
Publication Information
Journal of radiological science and technology / v.33, no.2, 2010 , pp. 133-141 More about this Journal
Abstract
The evaluation of Varian enhanced dynamic wedges (EDW) were performed in terms of quality assurance in external radiotherapy. The seven (10, 15, 20, 25, 30, 45, 60 deg.) EDW angles were evaluated for 6 and 15 MV x-rays in Varian Linac. The STT (segmented treatment table) for a field were calculated and compared with actual movement of the jaw using Dynalog files in order to evaluate mechanical operation. Two dimensional array detector and an ionization chamber were used to measure dose distributions in phantom from Linac. The mechanical movement of jaw was agreed with its expectation and two dimensional dose distributions including beam profiles were in agreement with RTP data approximately. In comparison with RTP calculations the percentage difference of output dose values for 100 MU irradiation was less than 2.9% and measured wedge factor was less than 2.6%. These results are shown that there is no problem in clinical applications of EDW equipped on this linac.
Keywords
Dynamic wedge; Quality assurance; wedge factor;
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Times Cited By KSCI : 4  (Citation Analysis)
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