@misc{oai:repo.qst.go.jp:00074869,
 author = {佐方, 周防 and Yamasita, Wataru and 高瀬, 信宏 and Hoteida, Masahiro and Sasaki, Yosuke and Okumura, Hiroaki and Usiroda, Tota and 水野, 秀之 and Narita, Katsuhisa and 福村, 明史 and Sakata, Suoh and Takase, Nobuhiro and Mizuno, Hideyuki and Fukumura, Akifumi},
 month = {Mar},
 note = {Purpose
The external dose quality audit (EDQA) for radiotherapy photon beams is implemented by Association for Nuclear Technology in Medicine in Japan (ANTM). In 2010, ANTM expanded the object of EDQA to non-reference conditions of field size changes and wedge filter insertions. In this study, we report the results of EDQA and the present dose delivery status with non-reference beam in radiotherapy in Japan.
Material
Up to this time, ANTM audited 2205 beams of non-reference conditions. However we restricted the analysis to the data since Dec. 2013, because the Japan Society of Medical Physics issued new standard dosimetry protocol for radiotherapy in the end of 2012. The conditions audited are 5x5, 15x15, 20x20 and 25x25cm for field size changes, and 15, 30, 45 and 60 degrees for wedge filter insertions. The users (radiotherapy facilities) can select any conditions freely from both categories. In the EDQA by ANTM radiophotoluminescent glass dosimeters (RGD) are used as the detector. The doses of RGD irradiated by user are estimated by ANTM and compared to user’s stated doses.
Results
Until Aug. 2017, 1440 beams of non-reference conditions have been audited. The number of beams are classified into 471 of wedge filter insertions and 969 of field size changes. The means of the differences between stated and estimated dose were less than 0.5%, and the standard deviations of the differences were around 1% for every field size and wedge angle. These standard deviations are within the values which were estimated by ANTM when starting the non-reference condition audits.
Conclusion
The EDQA for non-reference condition beams of radiotherapy beams has been successfully carried out by ANTM. The results are as expected and it seems that the status of dose delivery to patient in radiotherapy facilities in Japan is also satisfactory., World Congress on Medical Physics and Bioengineering},
 title = {External dose audit for high energy radiotherapy photon beams of non-reference conditions using radiophotoluminescent glass dosimeter in Japan},
 year = {2018}
}