@article{oai:repo.qst.go.jp:00045411,
 author = {Mori, Shinichiro and Ko, Susumu and Ishii, Takayoshi and Nishizawa, Kanae and 森 慎一郎 and 幸 進 and 石居 隆義 and 西澤 かな枝},
 issue = {1},
 journal = {Medical Dosimetry},
 month = {Mar},
 note = {The recent broad adoption of four-dimensional CT (4DCT) scanning in radiotherapy has allowed the accurate determination of the target volume of tumors by minimizing image degradation due to respiratory motion. Although the radiation exposure of the treatment beam is significantly greater than that of CT scans used for treatment planning, it is important to recognize and optimize the radiation exposure in 4DCT from the radiological protection point of view. Here, radiation exposure in 4DCT was measured with a 16 multi-detector CT. Organ doses were measured using TLD chips inserted at respective anatomical sites of an anthropomorphic phantom. Results were compared with those with the helical CT scan mode. The effective dose measured for 4DCT was 24.7 mSv, approximately four times higher than that for helical CT. However, the increase in treatment accuracy afforded by 4DCT means its use in radiotherapy is inevitable. The patient exposure in the 4DCT could be of value by clarifying the advantage of the treatment planning using 4DCT},
 pages = {87--90},
 title = {Effective Doses in Four-dimensional Computed Tomography For Lung Radiotherapy Planning},
 volume = {34},
 year = {2009}
}