Autor: Shinichi Shimizu, Takeshi Nishioka, Seiko Hashimoto, Kenji Kagei, Kazuo Miyasaka, Hiroki Shirato, Xu Bo, Toshihiro Kitahara, Takuro Arimoto
Rok vydání: 1999
Předmět:
Zdroj: Journal of Radiosurgery. 2:239-245
ISSN: 1096-4053
DOI: 10.1023/a:1022974111136
Popis: Stereotactic irradiation (STI) of lung tumors may be accomplished with a linear accelerator by administering several noncoplaner arcs of a narrow beam focused at the center of target volume with a better immobilization device than conventional radiotherapy. The shape of the radiation distribution produced by this technique is affected by the field size, the number of arcs, the separation angles of the arcs, and the location of the tumor. The influence of these parameters on the resulting radiation distributions was analyzed by computing dose–volume histograms (DVH) for a typical lung. Dose–volume functions were computed for: (1) 1–12 arcs; (2) 20–45° separation angles of arc, (3) 80°–160° of gantry roration; and (4) 5 tumor locations using 4 × 4 cm2 rectangular fields. Analysis was based on the hypothetical set up without obstacles, such as the head and arms, and then extended to the practical set up, which is usable in daily practice. Dose–volume statistics showed that five non-coplanar 120° arcs and one 80° arc at different six positions of patient couch with a 30° separation between arcs may be one of the reasonable techniques for irradiation of tumors at the approximate center of the right lung. For tumors situated at more peripheral locations, smaller volume of lung receives dose of 20% to 90% of prescribed dose. Our study provides a basis for further analysis of STI for lung cancer and has the potential to be a treatment strategy for this disease.
Databáze: OpenAIRE
Externí odkaz: