@inproceedings{oai:repo.qst.go.jp:00054296,
 author = {Tanaka, Rie and Ichikawa, Katsuhiro and Mori, Shinichiro and Dobashi, Suguru and Kumagai, Motoki and Sanada, Shigeru and et.al and 田中 利恵 and 市川 勝弘 and 森 慎一郎 and 土橋 卓 and 熊谷 始紀},
 book = {Proceedings of SPIE},
 month = {Feb},
 note = {There is a concern that image lag may reduce accuracy of real-time target tracking in radiotherapy. This study was
performed to investigate influence of image lag on the accuracy of target tracking in radiotherapy. Fluoroscopic images
were obtained using a direct type of dynamic flat-panel detector (FPD) system under conditions of target tracking during
radiotherapy. The images continued to be read out after X-irradiations and cutoff, and image lag properties in the system
were then determined. Subsequently, a tungsten materials plate with a precision edge was mounted on to a motor control
device, which provided a constant velocity. The plate was moved into the center of the detector at movement rate of 10
and 20 mm/s, covering lung tumor movement of normal breathing, and MTF and profile curves were measured on the
edges covering and uncovering the detector. A lung tumor with blurred edge due to image lag was simulated using the
results and then superimposed on breathing chest radiographs of a patient. The moving target with and without image lag
was traced using a template-matching technique. In the results, the target could be traced within a margin for error in
external radiotherapy. The results indicated that there was no effect of image lag on target tracking in usual breathing
speed in a radiotherapy situation. Further studies are required to investigate influence by the other factors, such as
exposure dose, target size and shape, imaging rate, and thickness of a patients body.},
 pages = {000--000},
 title = {Effects of image lag on real-time target tracking in radiotherapy},
 volume = {7622},
 year = {2011}
}