T. Shimozato, K. Yasui, Hireto Kinou, Fumiaki Komatsu
{"title":"用放射性致色膜周期性测量固定龙门系统中的被动质子束宽度","authors":"T. Shimozato, K. Yasui, Hireto Kinou, Fumiaki Komatsu","doi":"10.4236/ijmpcero.2019.84017","DOIUrl":null,"url":null,"abstract":"Background and Aim: Irradiation methods such as double scattering method \nand spot scanning method have been used in proton beam treatment devices. \nIn the scattering method, a ridge filter or a range modulation wheel is used to \ncreate a spread-out Bragg peak, but the distribution at the patient position \nmay change due to positional deviation of the incident beam. Therefore, assessment \nof the incident position of the beam is very important even in the \nscattering method. To investigate the width and distribution of the proton \nbeam before entering the RMW, a radiochromic film was installed at the outlet \nof the transport pipe and the entrance of the profile-monitoring detector. Methods: In this study, the distributions of the beam at the exit of the transport \npipe and the entrance of the monitor detector were measured using \nfilms. The beam width was measured from the full width at half maximum of \nthe profile obtained from the distribution. Measurements were conducted \nevery month for 10 months. Results: Beams of widths ranging from 1.82 to \n2.30 mm in the horizontal direction and 4.25 to 5.33 mm in the vertical direction \nwere outputted from the exit of the transport pipe. Beams of widths \nranging from 2.16 to 2.67 mm in the horizontal direction and 4.06 to 5.31 \nmm in the vertical direction were outputted from the entrance of the monitor \ndetector. The maximum width fluctuation for 10 months was 0.55 mm in the \nhorizontal direction and 1.26 mm in the vertical direction at the entrance of \nthe monitor detector. Conclusions: The distribution was obtained before the \nproton beam was scattered by the scatterer, and then we propose a method to \nperiodically measure and monitor the changes in the beam distributions \nevery month.","PeriodicalId":14028,"journal":{"name":"International Journal of Medical Physics, Clinical Engineering and Radiation Oncology","volume":null,"pages":null},"PeriodicalIF":0.0000,"publicationDate":"2019-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Periodic Measurements of Passive Proton Beam Width Using Radiochromic Film in Fixed Gantry System\",\"authors\":\"T. Shimozato, K. Yasui, Hireto Kinou, Fumiaki Komatsu\",\"doi\":\"10.4236/ijmpcero.2019.84017\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"Background and Aim: Irradiation methods such as double scattering method \\nand spot scanning method have been used in proton beam treatment devices. \\nIn the scattering method, a ridge filter or a range modulation wheel is used to \\ncreate a spread-out Bragg peak, but the distribution at the patient position \\nmay change due to positional deviation of the incident beam. Therefore, assessment \\nof the incident position of the beam is very important even in the \\nscattering method. To investigate the width and distribution of the proton \\nbeam before entering the RMW, a radiochromic film was installed at the outlet \\nof the transport pipe and the entrance of the profile-monitoring detector. Methods: In this study, the distributions of the beam at the exit of the transport \\npipe and the entrance of the monitor detector were measured using \\nfilms. The beam width was measured from the full width at half maximum of \\nthe profile obtained from the distribution. Measurements were conducted \\nevery month for 10 months. Results: Beams of widths ranging from 1.82 to \\n2.30 mm in the horizontal direction and 4.25 to 5.33 mm in the vertical direction \\nwere outputted from the exit of the transport pipe. Beams of widths \\nranging from 2.16 to 2.67 mm in the horizontal direction and 4.06 to 5.31 \\nmm in the vertical direction were outputted from the entrance of the monitor \\ndetector. The maximum width fluctuation for 10 months was 0.55 mm in the \\nhorizontal direction and 1.26 mm in the vertical direction at the entrance of \\nthe monitor detector. Conclusions: The distribution was obtained before the \\nproton beam was scattered by the scatterer, and then we propose a method to \\nperiodically measure and monitor the changes in the beam distributions \\nevery month.\",\"PeriodicalId\":14028,\"journal\":{\"name\":\"International Journal of Medical Physics, Clinical Engineering and Radiation Oncology\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":0.0000,\"publicationDate\":\"2019-09-16\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"International Journal of Medical Physics, Clinical Engineering and Radiation Oncology\",\"FirstCategoryId\":\"1085\",\"ListUrlMain\":\"https://doi.org/10.4236/ijmpcero.2019.84017\",\"RegionNum\":0,\"RegionCategory\":null,\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"\",\"JCRName\":\"\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"International Journal of Medical Physics, Clinical Engineering and Radiation Oncology","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.4236/ijmpcero.2019.84017","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
Periodic Measurements of Passive Proton Beam Width Using Radiochromic Film in Fixed Gantry System
Background and Aim: Irradiation methods such as double scattering method
and spot scanning method have been used in proton beam treatment devices.
In the scattering method, a ridge filter or a range modulation wheel is used to
create a spread-out Bragg peak, but the distribution at the patient position
may change due to positional deviation of the incident beam. Therefore, assessment
of the incident position of the beam is very important even in the
scattering method. To investigate the width and distribution of the proton
beam before entering the RMW, a radiochromic film was installed at the outlet
of the transport pipe and the entrance of the profile-monitoring detector. Methods: In this study, the distributions of the beam at the exit of the transport
pipe and the entrance of the monitor detector were measured using
films. The beam width was measured from the full width at half maximum of
the profile obtained from the distribution. Measurements were conducted
every month for 10 months. Results: Beams of widths ranging from 1.82 to
2.30 mm in the horizontal direction and 4.25 to 5.33 mm in the vertical direction
were outputted from the exit of the transport pipe. Beams of widths
ranging from 2.16 to 2.67 mm in the horizontal direction and 4.06 to 5.31
mm in the vertical direction were outputted from the entrance of the monitor
detector. The maximum width fluctuation for 10 months was 0.55 mm in the
horizontal direction and 1.26 mm in the vertical direction at the entrance of
the monitor detector. Conclusions: The distribution was obtained before the
proton beam was scattered by the scatterer, and then we propose a method to
periodically measure and monitor the changes in the beam distributions
every month.