title: Evaluation of X-ray doses and their corresponding biological effects on experimental animals in cone-beam micro-CT scans (R-mCT2).
abstract: Studies show that the radiation dose received during a micro-CT examination may have adverse effects on living subjects. However, the correlations between the biological effects and the radiation doses have never been thoroughly evaluated in the majority of cases. In this study, we evaluated the biological radiation effects of measured radiation doses in ICR mice using cone-beam micro-CT scans. Long-term in vivo whole-body micro-CT scans of ICR mice were performed for a duration of 4 weeks. Although a scanning frequency of three scans per week is higher than that necessary for conventional studies, this study represents particular cases where the subjects may undergo an extreme number of examinations. The average X-ray dose of a CT scan measures 16.19 mGy at the center of a phantom and 16.24 mGy at an offset position of 7.5 mm from the center of the phantom. The total average dose at the center of the phantom during the 4-week scanning period was 194.3 mGy. No significant radiation effects were observed in the weight gain curves, organ weights, blood analyses, litter sizes, reared offspring sizes, and the histopathologic results. Therefore, it is unlikely that the measured doses for the CT scans caused any radiation damage in the mice.
authors.affiliation: National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage-ku, Chiba, 263-8555, Japan. happynob@nirs.go.jp.
authors.forename: Nobuyuki
authors.initials: N
authors.lastname: Miyahara
authors.affiliation: National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage-ku, Chiba, 263-8555, Japan.
authors.forename: Toshiaki
authors.initials: T
authors.lastname: Kokubo
authors.affiliation: Rigaku Co., 3-9-12 Matubara-cho, Akisima-Shi, Tokyo, 196-8666, Japan.
authors.forename: Yukihiro
authors.initials: Y
authors.lastname: Hara
authors.affiliation: Rigaku Co., 3-9-12 Matubara-cho, Akisima-Shi, Tokyo, 196-8666, Japan.
authors.forename: Ayuta
authors.initials: A
authors.lastname: Yamada
authors.affiliation: Rigaku Co., 3-9-12 Matubara-cho, Akisima-Shi, Tokyo, 196-8666, Japan.
authors.forename: Takafumi
authors.initials: T
authors.lastname: Koike
authors.affiliation: Nihon University School of Dentistry, 1-8-13 Surugadai Kanda, Chiyoda-ku, Tokyo, 101-8310, Japan.
authors.forename: Yoshinori
authors.initials: Y
authors.lastname: Arai
mesh_terms: D000818:Animals; D054893:Cone-Beam Computed Tomography; D005260:Female; D008297:Male; D051379:Mice; D008813:Mice, Inbred ICR; D011829:Radiation Dosage; D051598:Whole Body Imaging; D055114:X-Ray Microtomography
keywords: Micro-CT; Radiation damage on mice