Kamomae T, Miyabe Y, Sawada A, Oita M, Fujimoto T, Yano S, Nakata M, Nakayama S, Hiraoka M
Okayama Central Hospital, Okayama, Japan.
Kyoto University, Kyoto, Japan.
Med Phys. 2012 Jun;39(6Part11):3727. doi: 10.1118/1.4735164.
A newly introduced radiochromic film, the GAFCHROMIC EBT3, has been expected as much useful device for the IMRT dosimetry. The purpose of this study was to investigate the sensitivity and the uniformity of the films between an Epson ES-10000G flatbed scanner and a Vidar DosimetryPRO Advantage (Red) scanner.
Doses ranging from 1 cGy to 1600 cGy with 15-MV photon beam was irradiated to the film in a solid water phantom, respectively. All of the films were then digitized after irradiation using both two scanners. Sensitivities, local fluctuations of the film with two scanners were evaluated. Local fluctuations were defined as the relative (percent) standard deviation of the film response in ROIs (3 cmx3 cm).
As to the Vidar scanner, the sensitivity of the film was higher for low dose range (below <400 cGy). While, as to the Epson scanner, the sensitivity using the red color channel was higher than others for low dose range. At high dose range (above >400 cGy), the green color channel had higher sensitivity than others. The Vidar scanner exhibited the lower local fluctuations than the Epson scanner for all dose ranges. For the Epson scanner, the red color channel had the lower local fluctuations than the green and blue color channel for all dose ranges.
This study shows the characteristics of the new EBT3 films, in conjunction with the Epson ES-10000G flatbed scanner and the Vidar DosimetryPRO Advantage (Red) scanner.
一种新推出的放射变色胶片GAFCHROMIC EBT3有望成为调强放疗剂量测定的有用设备。本研究的目的是调查爱普生ES - 10000G平板扫描仪和维达尔剂量测定专业优势（红色）扫描仪之间胶片的灵敏度和均匀性。
在固体水模体中，用15兆伏光子束分别向胶片照射1厘戈瑞至1600厘戈瑞的剂量。然后使用两台扫描仪对所有照射后的胶片进行数字化处理。评估两台扫描仪下胶片的灵敏度和局部波动情况。局部波动定义为感兴趣区域（3厘米×3厘米）内胶片响应的相对（百分比）标准偏差。
对于维达尔扫描仪，胶片在低剂量范围（低于<400厘戈瑞）的灵敏度较高。而对于爱普生扫描仪，在低剂量范围使用红色通道时灵敏度高于其他通道。在高剂量范围（高于>400厘戈瑞），绿色通道的灵敏度高于其他通道。在所有剂量范围内，维达尔扫描仪的局部波动均低于爱普生扫描仪。对于爱普生扫描仪，在所有剂量范围内，红色通道的局部波动低于绿色和蓝色通道。
本研究展示了新型EBT3胶片与爱普生ES - 10000G平板扫描仪和维达尔剂量测定专业优势（红色）扫描仪相结合的特性。
