Author/Authors :
Futami، نويسنده , , Yasuyuki and Kanai، نويسنده , , Tatsuaki and Fujita، نويسنده , , Makoto and Tomura، نويسنده , , Hiromi and Higashi، نويسنده , , Akio and Matsufuji، نويسنده , , Naruhiro and Miyahara، نويسنده , , Nobuyuki and Endo، نويسنده , , Masahiro and Kawachi، نويسنده , , Kiyomitsu، نويسنده ,
Abstract :
A three-dimensional irradiation system using a broad beam has been installed for heavy-ion cancer therapy at the Heavy Ion Medical Accelerator in Chiba (HIMAC) facility. Only the target region is irradiated at the 100% dose level; the dose level at other parts of irradiated tissues is less, using a range shifter, a multileaf collimator and a compensator. The devices are the same as those used in two-dimensional irradiation, except that the setting values of the devices can be dynamically changed during the treatment. The thickness of the absorber and the aperture of the multileaf collimator are dynamically controlled during irradiation, so that the Bragg peak is swept in the depth direction and the Bragg peak outside of the target volume is blocked by the multileaf collimator. The performance of this system was checked by irradiation of a phantom using a 290 MeV/nucleon carbon beam. The dose distribution realized by this three-dimensional irradiation agreed satisfactorily with the planned one.
