@misc{oai:repo.qst.go.jp:00064333, author = {Kumagai, Motoki and Mori, Shinichiro and Imada, Hiroshi and Kandatsu, Susumu and Yasuda, Shigeo and 熊谷 始紀 and 森 慎一郎 and 今田 浩史 and 神立 進 and 安田 茂雄}, month = {Oct}, note = {One of the important factors in liver radiotherapy is considering the intrafractional movement, especially in carbon-ion beam treatment, because respiratory induced liver motion is relative larger than other thoracic and abdominal sites. As a result, particle range variation could be expected significant large due to density variation by replacing lung and liver densities. We, therefore, evaluated the intrafractional carbon ion dose variation using a 4DCT data set. Patients with liver cancer were subject to the 4DCT examination under free-breathing conditions. Planning target volume (PTV) were defined by adding internal margin of 1.0 ~ 1.2 cm to GTV. Compensating bolus was designed for the PTV at peak-exhalation phase. Carbon ion dose distributions were calculated by applying the compensating bolus to the 4DCT data set. We assessed 4D dose volume histograms (4D-DVH) by using deformable registration., 6th Japan-Korea Joint Meeting on Medical Physics (JKMP) and 11th Asia-Oceania Congress of Medical Physics (AOCMP)}, title = {Optimum Gating Window for Gated Carbon-ion Beam Liver Treatment Planning using 4DCT Data}, year = {2011} }