title: Dose profiles for lung and breast regions at prospective and retrospective CT coronary angiography using optically stimulated luminescence dosimeters on a 64-detector CT scanner.
abstract: OBJECTIVE
  The purpose of our study was to acquire dose profiles at critical organs of lung and breast regions using optically stimulated luminescence (OSL) dosimeters; assess the actual radiation dose delivered at retrospective and prospective computed tomography coronary angiography (CTCA).
  
  
  METHODS
  Using a chest CT phantom we applied a prospectively-gated step-and-shoot- and a retrospectively-gated helical mode on a 64-detector row CT scanner. Retrospective scan mode was used with and without electrocardiogram (ECG) based tube current modulation. OSL dosimeters were used to measure dose profiles. In the both scan modes we acquired dose profiles and determined the mean and maximum dose in left lung and in left breast regions.
  
  
  RESULTS
  In prospective mode, the mean dose was 21.53 mGy in left lung- and 23.59 mGy in left breast region. With respect to the retrospective mode, the mean dose with tube current modulation was 38.63 mGy for left lung- and 46.02 mGy for left breast region, i.e. 0.56 and 0.55 times lower than the mean dose without modulation.
  
  
  CONCLUSIONS
  The OSL dosimeter is useful for measurement of the actual radiation dose along z-axis at lung and breast regions in the prospective and the retrospective CTCA.
authors.affiliation: Department of Medical Physics, Faculty of Life Sciences, Kumamoto University, 4-24-1 Kuhonji, Kumamoto 862-0976, Japan. funama@kumamoto-u.ac.jp
authors.forename: Yoshinori
authors.initials: Y
authors.lastname: Funama
authors.forename: Katsuyuki
authors.initials: K
authors.lastname: Taguchi
authors.forename: Daisuke
authors.initials: D
authors.lastname: Utsunomiya
authors.forename: Seitaro
authors.initials: S
authors.lastname: Oda
authors.forename: Hiroo
authors.initials: H
authors.lastname: Murasaki
authors.forename: Yasuyuki
authors.initials: Y
authors.lastname: Yamashita
authors.forename: Kazuo
authors.initials: K
authors.lastname: Awai
mesh_terms: D000328:Adult; D001940:Breast / Q000528:radiation effects*; D017023:Coronary Angiography / Q000295:instrumentation*; D006801:Humans; D008163:Luminescent Measurements; D008168:Lung / Q000528:radiation effects*; D008297:Male; D055620:Optical Phenomena; D019047:Phantoms, Imaging; D011446:Prospective Studies; D011829:Radiation Dosage; D012189:Retrospective Studies