TY - GEN
T1 - Usefulness of GafChromic EBT film for dosimetry beyond 8.0 Gy
AU - Aoyama, Hideki
AU - Tokura, Shinsuke
AU - Azuma, Yoshiharu
AU - Goto, Sachiko
AU - Inamura, Keiji
N1 - Copyright:
Copyright 2021 Elsevier B.V., All rights reserved.
PY - 2009
Y1 - 2009
N2 - The objective of this study was to extend the usable dose measurement range of Gafchromic EBT film (EBT). EBT has the advantages of high sensitivity and improved film uniformity up to 8.0 Gy over Gafchromic MD-V2-55 film (MD-V2-55). EBT samples were exposed from 0.3 to 80 Gy. Optical densities of the samples were measured using ES-2200 (Seiko Epson Corporation, Nagano, Japan). EBT has an absorption spectrum with a maximum absorption band centered at 630 nm. The wavelength position of a maximum absorption does not shift with increasing dose within usable dose range. High sensitivity measurement of density can be performed using measurement light of 630 nm. We designed a flat-bed document scanner with single emission spectrum centered at 630 nm (IR-4000, iMeasure, Inc.) for EBT. Optical densities of the samples were also measured using IR-4000. The optical density response characteristics obtained by the combinations of EBT/ES-2200 and EBT/IR-4000 were compared with those of MD-V2-55/ES-2200. As a result, optical densities of EBT increased from 8.0 to 80 Gy. From the optical densities the calibration curves of net optical density versus delivered dose for dosimetry could be obtained. The combinations of EBT/ES- 2200 and EBT/IR-4000 had higher sensitivity of densitometry than MD-V2-55/ES-2200. The sensitivity of EBT/IR-4000 was highest. rror of dose measurements up to 80 Gy is within about ±5%, ±8%, and ±4% for MD-V2-55/ES-2200, EBT/ES- 2200, and EBT/IR-4000, respectively. The IR-4000 with single emission spectrum can bring out the capacity of high sensitivity and accuracy of EBT up to 80 Gy.
AB - The objective of this study was to extend the usable dose measurement range of Gafchromic EBT film (EBT). EBT has the advantages of high sensitivity and improved film uniformity up to 8.0 Gy over Gafchromic MD-V2-55 film (MD-V2-55). EBT samples were exposed from 0.3 to 80 Gy. Optical densities of the samples were measured using ES-2200 (Seiko Epson Corporation, Nagano, Japan). EBT has an absorption spectrum with a maximum absorption band centered at 630 nm. The wavelength position of a maximum absorption does not shift with increasing dose within usable dose range. High sensitivity measurement of density can be performed using measurement light of 630 nm. We designed a flat-bed document scanner with single emission spectrum centered at 630 nm (IR-4000, iMeasure, Inc.) for EBT. Optical densities of the samples were also measured using IR-4000. The optical density response characteristics obtained by the combinations of EBT/ES-2200 and EBT/IR-4000 were compared with those of MD-V2-55/ES-2200. As a result, optical densities of EBT increased from 8.0 to 80 Gy. From the optical densities the calibration curves of net optical density versus delivered dose for dosimetry could be obtained. The combinations of EBT/ES- 2200 and EBT/IR-4000 had higher sensitivity of densitometry than MD-V2-55/ES-2200. The sensitivity of EBT/IR-4000 was highest. rror of dose measurements up to 80 Gy is within about ±5%, ±8%, and ±4% for MD-V2-55/ES-2200, EBT/ES- 2200, and EBT/IR-4000, respectively. The IR-4000 with single emission spectrum can bring out the capacity of high sensitivity and accuracy of EBT up to 80 Gy.
KW - Dose measurement range
KW - Extension
KW - Flat-bed document scanner
KW - Gafchromic EBT film
KW - Gafchromic MD-V2-55 film
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U2 - 10.1007/978-3-642-03474-9_57
DO - 10.1007/978-3-642-03474-9_57
M3 - Conference contribution
AN - SCOPUS:77950453213
SN - 9783642034725
T3 - IFMBE Proceedings
SP - 200
EP - 203
BT - World Congress on Medical Physics and Biomedical Engineering
PB - Springer Verlag
T2 - World Congress on Medical Physics and Biomedical Engineering: Radiation Oncology
Y2 - 7 September 2009 through 12 September 2009
ER -