Analysis of effects of body sizes on organ doses due to CT examinations by using voxel phantoms

Sato, Kaoru   ; Takahashi, Fumiaki  ; Koba, Yusuke*; Ono, Koji*; Yoshitake, Takayasu*; Hasegawa, Takayuki*; Katsunuma, Yasushi*; Kasahara, Tetsuji*; Okuda, Yasuo*; Nakada, Yoshihiro*; Akahane, Keiichi*; Kanda, Reiko*; Kai, Michiaki*

JAEA is now developing CT dose calculator named WAZA-ARIv2 in cooperation with the National Institute of Radiological Sciences. WAZA-ARIv2 has been opened to the public as full-dress uses on January 2015. WAZA-ARIv2 can perform dose assessment against 4 different body physiques by using the organ dose database, which were constructed on the basis of adult Japanese phantoms with 4 body sizes (-2, average, +2, +5). In this study, it was found that salivary gland doses are independent on BMI, whereas lung doses are dependent on BMI. The differences in the effects of BMI on absorbed doses between salivary glands and lungs might be caused by the difference in thickness of subcutaneous soft tissues between head and thorax.