TITLE:
Comparison of the Motion Accuracy of a Six Degrees of Freedom Radiotherapy Couch with and without Weights
AUTHORS:
Akihiro Takemura, Shinichi Ueda, Kimiya Noto, Hironori Kojima, Naoki Isomura
KEYWORDS:
6D Couch; IGRT; Accuracy Assessment
JOURNAL NAME:
International Journal of Medical Physics, Clinical Engineering and Radiation Oncology,
Vol.2 No.3,
July
26,
2013
ABSTRACT: In this study, we compared the motion accuracy of six degrees of freedom (6D) couch for precision radiotherapy with or without weights attached to the couch. Two digital cameras were focused on the iso-center of a linear accelerator. Images of a needle which had been fixed to the 6D couch were obtained using the cameras when the couch moved in translation and rotation around each axis. The three-dimensional (3D) coordinates of the needle were calculated from coordinate values in the images. A coordinate error of the needle position relative to the theoretical position was calculated. The errors were obtained with or without a 60 kg weight attached to the 6D couch, and these errors were compared with each other. The mean distance of the 3D error vectors for the weighted test was 0.21 ± 0.11 mm, and >0.16 ± 0.09 mm for the non-weighted test (p p