Scanning orientation effects on Gafchromic EBT film dosimetry

被引：92
作者：
Butson M.J. [1 ,2 ]
Cheung T. [1 ]
Yu P.K.N. [1 ]
机构：
[1] City University of Hong Kong, Department of Physics and Materials Sciences, Kowloon Tong
[2] Illawara Cancer Care Centre, Department of Medical Physics, Wollongong, NSW 2500
来源：
Australasian Physical and Engineering Sciences in Medicine | 2006年 / 29卷 / 03期
关键词：
Densitometry; Gafchromic EBT; Orientation; Radiochromic film;
D O I：
10.1007/BF03178579
中图分类号：
学科分类号：
摘要：
Gafchromic EBT film, a new high sensitivity radiochromic film has been tested for variations in optical properties due to scanning orientation. Gafchromic EBT film has been shown to produce a scanning orientation effect whereby variations in measured relative optical density are found due to the films orientation relative to the scanner direction. This relative optical density change was found to be relatively consistent for different films exposed to varying dose levels ranging from 0 Gy to 3 Gy. A maximum variation of 0.0157 ± 0.0035 in optical density (OD) was found. This relates to an approximate 15% variation in net OD for a 50 cGy irradiated film and 4% variation for a 3 Gy irradiated film. No noticeable effects or variations were seen with changing scanning resolution or with the film placed "up or down" during scanning. Other Gafchromic film types were tested and compared to EBT for unirradiated film to assess the magnitude of this orientation effect on the scanner used and results showed that EBT produced a significantly higher effect that MD-55-2, HS, XR type T and XR type R film by up to 3 times. As such, providing the same orientation of EBT film when scanning for dosimetric analysis becomes an essential part of EBT film dosimetry. Copyright © 2006 ACPSEM/EA.
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页码：281 / 284
页数：3
相关论文
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