AbstractObjective To explore and establish accurate detection quality control method of source positioning and timer precision for afterloading equipment. Methods The source positioning detection device was made of hd camera,EBT3 disposable film and steel rule,collecting source in each resident point for video images and film. Accurate measurement of radioactive source positioning and timer accuracy,including the timing absolute error and linear error through analysis of image sampling rate. After the film grayscale distribution analysis,comparison between film gray peak position and the measurement of resident point geometry,got the stay point source physics and radiation center deviation. Results Radioactive source physics and radiation center deviation was (-0.33±0.10) mm;For all default dwell time,timer average absolute deviation was (0.22±0.02) s,linear fitting result was y=x-0.226,R2=1,timing linear error was -0.01% Conclusions established detection means through the video images and film exposure quantitative analysis for accurately determination of source positioning,dwell time and source radiation center precision. After experimental testing the machine precision satisfied the requirement of clinical use.
Yu Lang,Yang Bo,Liu Xia et al. Quality control of source positioning and timer accuracy for high-dose rate afterloading machine[J]. Chinese Journal of Radiation Oncology, 2018, 27(6): 598-600.
Yu Lang,Yang Bo,Liu Xia et al. Quality control of source positioning and timer accuracy for high-dose rate afterloading machine[J]. Chinese Journal of Radiation Oncology, 2018, 27(6): 598-600.
[1] Karlsson J,Dreifaldt AC,Mordhorst LB,et al. Differences in outcome for cervical cancer patients treated with or without brachytherapy[J].Brachytherapy,2016,16(1):133-140.DOI:10.1016/j.brachy.2016.09.011 [2] DeWerd LA,Jursinic P,Kitchen R,et al. Quality assurance tool for high dose rate brachytherapy[J].Med Phys,1995,22(4):435. [3] Nath R,Anderson LL,Meli JA,et al. Code of practice for brachytherapy physics:report of the AAPM Radiation Therapy Committee Task Group No.56.American Association of Physicists in Medicine[J].Med Phys,1997,24(10):1557-1598. [4] Li Wei, He Yibin,Song Long, et al. Measuring Method Based on 2D Image[J]. Tool Engineering,2017,51(2):111-113.DOI:10.3969/j.issn.1000-7008.2017.02.028. [5] Venselaar J. A practical guide to quality control of brachytherapy equipment[J]. Vol Booklet, 2004, 8. [6] Evans MDC,Devic S,Podgorsak EB.High dose-rate brachytherapy source position quality assurance using radiochromic film[J].Med Dosimet,2007,32(1):13-15.DOI:doi:10.1016/j.meddos.2006.10.001. [7] Wilkinson DA.High dose rate (HDR) brachytherapy quality assurance:a practical guide[J].Biomed Imag Intervent J,2006,2(2):e34.DOI:10.2349/biij.2.2.e34. [8] Harpool K,Herman TDLF,Ahmad S,et al. SU-F-T-32:Evaluation of the performance of a multiple-array-diode detector for quality assurance tests in high-dose-rate brachytherapy with Ir-192 source[J].Med Phys,2016,43(6Part13):3468-3468.DOI:10.1118/1.4956167
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