原 著 原 著GAF chromic dosimetryの特性とPDD，OCR曲線への利用
Contents
1.2. 1364 0000 10 11 ST dela Zerda A Lin etal High sensitivity 5 20 48 611 1995 GafChromic film dosimary for 2251 seed M ed Phys 21 50 651 2 657 19941 pp 80 82 120 Meigooni AS and Nath R Photon energy de I 1989 pendence of the sensitivity of radi ochromic film com 3jHumpherys
3. 00000 MD 550 HD 810 0000000000000000 6060100090 0000 11 250 000 19210 000000000 0 4 000000000 MD 550 12 5 12 5 278 0 810 20 25c 1070 0 0 0 00 00000 1 3 1 3 1 550000 LI 00000 51 4000 0 0O 26 c0 O 0O O 0 MD 550 0 000 00000000 90 4000 0000 0 0 0 000 10 10 1000000000000 10 20 30 100 0 2 2 00000 4000 50000000000000 00000000 0 0 37 4330 00 000 02000000000 0000000 55 10MV 0 050 1 0Gy 0 030 0 2Gy 0 0 1 0 1 0 0 20 100 50Gy0 0 50 10Gy0 00000 250 0 0000 Solidwater
4. 0 1000 000000240000 0000000000 1362 000 I Z un MA MEE MD 55 MD 55 2 5 nn ajal 1 2 x G HD t 2 6 HD 811 1 4 2 20 j 5 ga zu G p E T 1 2 15 r m EE EE We T 5 10 i 05 0 5 E I T hi4 kh la Ls Uc mp n a BSO na 150 i ki H T I xm Wave lengthinm E E pj Timethr Fig 7 Characteristics of GAF types MD 55 and HD 810 were compared a l he absorbed spectrum of each type of after exposure to 30 Gy b IJC hange in optical density according to time c IChange in optical density according to absorbed dose c
5. 2001 11 MD 550 Hb 81g 0 0 Xv n0 0 0 0X000000 000000000 3 3 x 30x 3 solid 000 1 890 00000 220000 0000 10MV 0 10x 10 00000000 00000000 0 0 0 MD 550 HD 8100 0000 0 59 20Gy 810 130Gy PDDI 0 00 LU 0000 solid wae 0000000 15 trtum MD 550 135yn 810 80Gcy H 000000000000000 000000000000 0 bpr3 PODO OCRO 000000000000 00 000000 0000 0000 0000000 1000000000 7 40 200 0 2 1 55 2 1 1 00000 Fig 55 0 000000 0 100000000000060 0000002400000 0000 0000 26900 0 00000 2 1 2 0000000 Fig 20 MD 559 000000000000000 Fig
6. chromic dosimetry PDD OCR LE 1 1357 0 0 F chromic dosimetry 0 0 I LI I LU D I EE EF ELE EE ELE E EE EE ET EE EE EE EE 10000 20000 8021 20010 705 11 851 u Evaluation GAF Chromic Dosimetry and Its Application to PDD and OCR Curves YASUSHI YAMAMOTO SHINOBU TAKAHASHI AKIO KOMATSU NOBUE UCHIDA HIROKAZU KATO Department of Radiology Shimane Medical University Hospital l Department of Radiology Shimane Medical University 2 Faculty of Health Sciences Okayama University Medical School Received Aug 21 2000 Revision accep
7. 27 0 10 Moda 37 4330 0 0 000 0300000000 000000000 0 0 10 x0 0 4AMV XII 56 0000000 1 3 2 ALTI D D D 57 11 chromic dosimetry PDD OCR 1359 00200 000 000000000 L Ig 10 00 r lod 7o L Hog 1700 AL 00000 ebsorbancd ri 0 0 00 0000 1 3 2 00000000
8. Percent depth dose ff center ratio 00000000 0 693 0021 000000000 89 1 0000 D 2001 11 1358 GAF Chromic 000 0000 0000 0000 TypeMD 5x HD 8100 0 000000000000 000000 55000 00000 000 0 00 100 0 1 1 00 GAF GAF Chromic Media Type 55 0000 MD 550 Type HD 810 00 HD 810 Associates 00 4 0000000000 00000 Radiochromic Densitometer M oda 37 438 Nuclear Associates Densitometer 151 000 Linear ML 15MDX MITSUBISHI Electorid 0 IONEX Dosemaester 2590 J ARPO TECHNOLOGYTI 0 0 W23333 0 0 O 00000 RMID 0O 0 000 Spectro Photometer U 2000 O 0 Model 195 20 0 0 0 0 030 rdg 0 0 000000000 Mitsubishi Depth Profile M onitor 3 Dpro3r 000 20000000 000000 20 000 1 2 00000
9. 672nni Fig 8 X GAF Dpro3 PDD 10MV X Fig 9 X GAF Dpro3 OCR 10MV X 10cmx 10cnid Tabe X Dpro3 PDD 57 11
10. 98 0 672 5mm 000 00000 00 0 00 00 0 Flatness 1 05 1 07 1 09 1 10 uagamBmuugamdiutdegznataznuastarttl Symmetry 1 30 1 020 1 013 1 014 1 006 0000000000000000000 0 2 30 1 025 1 013 1 027 1 009 Peak mmi 26 08 2705 2672 27 00 000000 00 00 0 0 00 57 10 chromic dosimetry PDD OCR D 1363 1L 1 107 0000 0007 Fact I 000000000 580 7 D DO DO 700 E ola 10 14 667m0 0 677m am 700 a cb T 10 dA 580 04 667 677 700 1 580 0A 107 C I 1077 dA 1 197 667 677 700 14 621 9 f 1 4 Z0 B D UU UO C C UE D amp U U U ALI CI UU U FU UU 0000 0000 eeenni 0 ezemr 0000000000 000000 00 0 0 5800 667nni 0 0 6770 700 00000 gt 677 a cb N kolo 10 677 ko 145 b 000000000 2001 11 000070 20000 00 00 5800 667m 0 000 6770 700
11. ayggumuusumnuupnguamgagamnugmnmuagut 6080 13 8260 0 001 10 5Gy Gy23 07D 13 5320 0 017 0 0 1 00 00000 0 08 Model 37 433 0000000000000 0000 002100 0 00000 00000 0000 2 1 3 00000000 Fig 00 0000 0000 0 0 0 0 0 00 0 00000000000 551 0100000000 00 00000000000 00 550 000 0 1360 ggagaaaaadatt 20 15 21 5 E m E F x 0 10 B r m A ri 0 054 EN E 5 4 0 5 10 ib 20 300 400 6 Timethr Fig 1 Change in the optical density of GAF type MD 55 measured by Radiochromic Densitometer Model 37 433 according to time in room light Abscissd a zero to 24 hours after b zero to 400 hours after ex posure 3 07002 13 5320 0 017 1 60802 13 8260 0 017 2 0 997 5 1 05 idt n LM II 5n b Fig 2 Change in the optical density GAF type MD 55 measured by Radiochromic Densitometer Model 37 433 according to absorbed dose Abscissd dose changed from 0 05 to 5 0 Gy b jabsorbed dose changed from 0 05 to 50 0 Gy 0 4 2 0 X Ray n X Ray z MeNV Electoran 5 z E o z 0 1 0 1 2 3 1 5 000 000 00 Dise y Wave lengthi
12. were measured by a Micro P ho tometer with a 672 nm Band Pass Filter 100 1 mai ei i 75 E T5 L z s mea Fiim i gt gt m m s m MLD BBR Es nl variation 10 n 015 13 15 0 019 Dpro3 Hr sin 0 T ED 100 150 200 260 70 60 b dt H0 2 18 0 10 29 30 40 30 0 Distance from center nq Fig 8 The percent depth dose curves derived by GAF types Fig 9 The off center ratio curves derived by GAF types MD MD 55 and HD 810 were compared with those de 55 and HD 810 were compared with those derived rived by x ray film and Dpro 3 by x ray film and Dpro 3 The spindle represents relative percent dose and the abscissa represents off axis distance Table The data obtained from x ray film GAF type MD 55 GAF type HD 810 and Dpro 3 were compared The size of the radiation field flatness and sym pmagmaubrmtutarmtdrtgbr tturbrrtubr t metry were derived from the off center ratio curve 0000000000000000000 Peak depth was derived from the percent depth dose curve uugumumuuuuulaedalllutdtattatdttutt 0000000 4 0 300 700nn11 0 0D00000000000 90000000000 Film MD 55 HD 810 Radiation field mmg 100 1 101 5 101 3
13. 000000 37 4330 0 000000000000100 1 000 optical density Gy T 1 L1 00000000 00 o25mmx 0 GP IB 1 3 3 81008 0 0 0 0 O 55 0100 MD 550 12 5 12 5 0000000000 20 25 1 0000000 8101 51 1 3 4 OOCR E tutt 0D0 000000000000000000 000 100 1 1 1
14. 000000600 672m0 0000000000000 0 0 80 0 00000000 90 2 3 HD 810 810 55 00000000000000 Fig 0 000 000 00 0 0 0 0000 MD 53 00000 0000 00 0000 00000 000 240 00000 15500 0000000600 1010000 HD 8100 MD 550 6000000000000 Fig 7d I 2 4 00000 quality assurancB QAITI LI L1 0 Fig g B Xi Dna gd B B 0 0 0 0 0 0 PDD 0000000000000000 00 0 0O 2001 11 Fiber WRATTEN Fiter Filter Net Optical eH 10 20 Fig 6 Change in the optical density of GAF type MD 55 measured without a filter with a 672 nm Band Pass Filter and with a WRATTEN Filter 000000 Fig 81 00 00 000 00000 9 9 00000000 00 0000 0000000000000 000 0 0 0000000000000 00 000 0 0 0 0 0 00000 14mmy 000 4 0 000 1 30 0 007 00 2 30 0 012m 0 000 0 97 000000000 0000000 uU uu 300 0
15. and Kantz AD Radiochromic A radiation parison with silver halide film and LiF TLDs used for monitoring system Radiat Phys Chem 9 737 747 19771 brachytherapy dosimery M ed Phys 18 40 769 775 19911 4 SP Data Sheet chromic MD 55 dosi metry medi um 13 Reinstein LE Gluckmam GR and Amols Predicting op International Special Products 19991 tical densi tometer response as a function of light source charac 5 Niroomand Rad Azam Blackwell CR Coursey BM amp al teristics for radiochromic film dosi mary M ed Phys 24 12 Radiochromic film dosi mary Recommendations of AAPM 1935 1942 199 Radiation Therapy Comrrittee Task Group 55 M ed Phys 25 14 11 20980 19980 166 601 172 19961 95 96 LI 1998 15 63 66 3 111 114 I 1998 1994 16 j McLaughlin WL un Dong Soares al Sensito 8 metry of the response of a new radiochrorric film dosi meter 19921 to gamma radiation and electron beams Nuclear Instruments 9 and Methods in Physics Research A 302 165 176 North 7B 511 58 61 T 20011 Holland 19911 10 1 100 X I 1994 20 401 92 93 2000 00000 Fig 1 MD 55 LI Model 37 433 LE a4 T 60400 Fig 2 MD 55 I Model 37 433 T 0 05Gy 5 0Gy I 0 05Gy 50 0Gy Fig 3 MD 55 10MV X 4MV X 6M ev 5Gy Model 37 433 Fig 4 MD 55 11 50Gyl Fig 5 672nm Fig 6 672 1 7 HD 810 55 30Gy bI TI LE amp 0 amp 0
16. m0 0000000000000 20000 000 000 000 000 00 0 0000000000000 0000000 0 0 Mode 37 4330 00000000000000 PODO 0 91 5510 000000 401 000000
17. nml Fig 3 The energy dependency of GAF type MD 55 sensi Fig 4 The absorption spectrum of GAF type MD 55 with tivity was compared between the following the opti cal density obtained by GAF exposed with 10 MV x rays 4 MV x rays and a 6 MeV electron beam Optical density was measured by Radiochromic Den sitometer Model 37 433 various absorbed doses The abscissa represents wave length nmi 0 570 10 chromic dosimetry PDD OCR 1 1361 4 0 Band Pass iac WEATTEH Filber E TTEM Fili J i N a Aha rbanee tiom 650 75D Wave Fig 5 The absorbed spectrumof a 672 nm Band Pass Filter and a WRATTEN Filter The abscissa represents wave length nmi 0 0460 00 O 0 0160 0O 0 0 79 1 2 1 4 0000 Fig 40 0 0 000 55 00 0000 0 000 000000000000 6700 000 20 0 40600000 150 25 1000 000 0 000 00 22 Fig 00 0000 0000 00 0000 0 000 0000 672 5 000 60 10 500000000940 00
18. ted July 5 2001 Code No 851 Summary GAF Chromic Dosimetry Medig GAF Media Nuclear Associates Co Ltd has been newly developed for the purpose of absorbed dose measurements with ionizing radiation GAF Media is colorless and trans parent before radiation exposure and it changes progressi vel y to a darker blue color with exposure n contrast to conventional film GAF Media can be used in room light and does not require any other procedure to develop or fix the image In this study we used microdensitometer to evaluate the relationship between the absorbed dose and optical density of GAF Media types MD 55 and HD 810 We discuss the possibility of application of GAF Media as a simple dosimeter of percent depth dos off center ratig OCR in thefield of quality assuranda QA of radiotherapy The optical density derived by GAF Media could be converted into absorbed dose by using an approximation curve However the elevation of baseline density th fog effect according to time was too great to be neglected To measure the absorbed spectrum of GAF Media microdensitometer attached with a Band Pass Filter which selectively absorbed the spectrum at 671 nm was useful The PDD and OCR curves derived by GAF M edia were accurate enough for QA of radiotherapy GAF Media was simple to use but further investigation will be required before applying it in other fields Key words GAF Chromic film Radiochromic film Film detector
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