Validation of dose assessment system for CT diagnosis

Yoshitake, Takayasu*; Ono, Koji*; Hasegawa, Takayuki*; Katsunuma, Yasushi*; Sato, Kaoru   ; Takahashi, Fumiaki  ; Endo, Akira   ; Ban, Nobuhiko*; Kai, Michiaki*

Since 2000s, computed tomography (CT) examination has significantly increased at medical treatment in Japan. Therefore, it is very interested in radiation exposure doses derived from CT examinations. We started development of a web-based system, named WAZA-ARI, which can assess radiation doses more accurately now in Japan in 2007. So far a beam-shaping (bow-tie) filter was newly constructed for the X-ray source model of CT device by using PHITS code. In this study, CTDI phantom, which dosimeter was placed in center or periphery, was irradiated with X-ray of CT device. In order to validate WAZA-ARI, measured values were compared with calculated values by PHITS code. The dose differences of center in CTDI phantom between measurement and calculation were within 2-5%.