title: Experimental evaluation of analytical penumbra calculation model for wobbled beams.
abstract: The goal of radiotherapy is not only to apply a high radiation dose to a tumor, but also to avoid side effects in the surrounding healthy tissue. Therefore, it is important for carbon-ion treatment planning to calculate accurately the effects of the lateral penumbra. In this article, for wobbled beams under various irradiation conditions, we focus on the lateral penumbras at several aperture positions of one side leaf of the multileaf collimator. The penumbras predicted by an analytical penumbra calculation model were compared with the measured results. The results calculated by the model for various conditions agreed well with the experimental ones. In conclusion, we found that the analytical penumbra calculation model could predict accurately the measured results for wobbled beams and it was useful for carbon-ion treatment planning to apply the model.
authors.affiliation: Department of Medical Physics, Research Center for Charged Particle Therapy, National Institute of Radiological Sciences, 4-9-1, Anagawa, Inage-ku, Chiba, Chiba 263-8555, Japan. r_kohno@nirs.go.jp
authors.forename: Ryosuke
authors.initials: R
authors.lastname: Kohno
authors.forename: Nobuyuki
authors.initials: N
authors.lastname: Kanematsu
authors.forename: Ken
authors.initials: K
authors.lastname: Yusa
authors.forename: Tatsuaki
authors.initials: T
authors.lastname: Kanai
mesh_terms: D000465:Algorithms; D002250:Carbon Radioisotopes / Q000627:therapeutic use; D003198:Computer Simulation; D063193:Heavy Ion Radiotherapy; D008954:Models, Biological; D011874:Radiometry / Q000379:methods*; D019275:Radiopharmaceuticals / Q000627:therapeutic use; D011879:Radiotherapy Dosage; D011880:Radiotherapy Planning, Computer-Assisted / Q000379:methods*; D015203:Reproducibility of Results; D012542:Scattering, Radiation; D012680:Sensitivity and Specificity
chemical_list: D002250:Carbon Radioisotopes; D019275:Radiopharmaceuticals