Abstract：
PURPOSE:Several works have recently focused on flattening-filter-free (FFF) beams of linear accelerators of various companies (in particular, Varian and Elekta), but no overview as yet exists for the flattening-filter free 7XU beam (Siemens Artiste). METHODS:Dosimetric properties of the 7XU beam were measured in May and September 2011. We present depth dose curves and beam profiles, output factors, and MLC transmission and assess the stability of the measurements. The 7XU beam was commissioned in the Pinnacle[superscript three] treatment planning system (TPS), and modeling results including the spectrum are presented. RESULTS:The percent depth dose curve of the 7XU beam is similar to the flat 6X beam line, with a slightly smaller surface dose. The beam profiles show the characteristic shape of flattening-filter free beams, with deviations between measurements of generally less than 1%. The output factors of the 7XU beam decrease more slowly than for the 6X beam. The MLC transmission is comparable but slightly less for the 7XU beam. The 7XU beam can be adequately modeled by the Pinnacle[superscript three] TPS, with successful dosimetric verification. The spectrum of the 7XU beam has lower photon fluence up to approximately 2.5 MeV and higher fluence beyond, with a slightly higher mean energy. CONCLUSIONS:The 7XU beam has been commissioned for clinical use after successful modeling, stability checks, and dosimetric verification.
journal_name
Med Physjournal_title
Medical physicsauthors
Dzierma Y,Licht N,Nuesken F,Ruebe Cdoi
10.1118/1.3703835subject
Has Abstractpub_date
2012-05-01 00:00:00pages
2595-602issue
5eissn
0094-2405issn
2473-4209journal_volume
39pub_type
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