title: Estimate of organ radiation absorbed doses in clinical CT using the radiation treatment planning system.
abstract: Organ absorbed doses in computed tomography (CT) scans can be measured with anatomical phantoms but not inside the human body. In this study, a straightforward method was investigated to estimate organ doses in clinical CT using the radiation treatment planning system (RTPS) and compared them with experimental results of photoluminescence dosemeters (PLD). In a heterogeneous phantom, the average difference between PLD and RTPS values were -5.0% for the body and 7.1% for the lung. Using CT data, organ doses in 30 clinical cases were then calculated. There was a significant inverse correlation between the calculated values of organ doses and body mass index (BMI, correlation coefficients (r) = -0.69 (whole body), -0.80 (right lung), -0.81 (left lung), -0.76 (spinal cord), -0.74 (vertebra bone), -0.74 (heart), and -0.79 (oesophagus), all p < 0.01). An RTPS can be a simple and useful tool for estimating equivalent doses inside the human body, during whole-body CT scans.
authors.affiliation: Graduate School of Comprehensive Human Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8575, Japan. fujibuchi@ipu.ac.jp
authors.forename: Toshioh
authors.initials: T
authors.lastname: Fujibuchi
authors.forename: Nobusada
authors.initials: N
authors.lastname: Funabashi
authors.forename: Masatoshi
authors.initials: M
authors.lastname: Hashimoto
authors.forename: Hideyuki
authors.initials: H
authors.lastname: Kato
authors.forename: Masayuki
authors.initials: M
authors.lastname: Kurokawa
authors.forename: Hossain M
authors.initials: HM
authors.lastname: Deloar
authors.forename: Etsuo
authors.initials: E
authors.lastname: Kunieda
authors.forename: Issei
authors.initials: I
authors.lastname: Komuro
authors.forename: Takeji
authors.initials: T
authors.lastname: Sakae
mesh_terms: D015992:Body Mass Index; D006801:Humans; D009010:Monte Carlo Method; D019047:Phantoms, Imaging; D011829:Radiation Dosage; D011835:Radiation Protection; D013902:Radiography, Thoracic; D011880:Radiotherapy Planning, Computer-Assisted / Q000706:statistics & numerical data*; D014057:Tomography, X-Ray Computed; D014916:Whole-Body Irradiation