TY - JOUR
T1 - Dose distribution in pediatric CT head examination
T2 - Phantom study
AU - Gotanda, R.
AU - Katsuda, T.
AU - Gotanda, T.
AU - Tabuchi, A.
AU - Kuwano, T.
AU - Yatake, H.
AU - Yabunaka, K.
AU - Akagawa, T.
AU - Sato, H.
AU - Takeda, Y.
PY - 2011/11/9
Y1 - 2011/11/9
N2 - To keep radiation doses during computed tomography (CT) examinations as low as reasonably achievable, performing a detailed dose measurement is important. A flexible acrylic sheet roll CT dosimetry phantom (SRCT-P) with radiochromic film (RF) was developed to estimate in detail the dose distribution during pediatric CT examination. The SRCT-Ps were cylindrically-shaped by rolling up flexible acrylic sheets (1.1 g/cms). The dose distributions in the SRCTP (diameters of 6 cm [premature baby], 10 cm [neonates], and 14 cm [infants]) were evaluated. RFs were positioned every 5 mm along the radius at each SRCT-P, starting at center and ending on the surface. In this study, the absorbed dose and the dose distribution in the phantom were measured at 100 or 120 kV of the x-ray tube voltage. The other scanning parameters of the CT were 250 mA, 1.0 sec/rot, 1.25 x 8 mm slice thickness, and a 1.0 beam pitch. The mean center doses at 100 or 120 kV in 6, 10 and 14 cm of the SRCT-P were 37.0 or 64.2 mGy; 36.5 or 52.2 mGy; and 19.5 or 40.2 mGy, respectively. The mean surface doses in 100 or 120 kV at 6, 10 and 14 cm of the SRCTP were 33.9 or 57.9 mGy; 34.0 or 46.8 mGy; and 20.0 or 47.3 mGy, respectively. The absorbed dose was increased with a decrease in the phantom size. However, at 100 kV, the mean depth dose distributions at 6 or 10 cm of the SRCT-P were shown about the same value. The results indicated that the dose distribution in pediatric head CT becomes complex with patient head size and the tube voltage.
AB - To keep radiation doses during computed tomography (CT) examinations as low as reasonably achievable, performing a detailed dose measurement is important. A flexible acrylic sheet roll CT dosimetry phantom (SRCT-P) with radiochromic film (RF) was developed to estimate in detail the dose distribution during pediatric CT examination. The SRCT-Ps were cylindrically-shaped by rolling up flexible acrylic sheets (1.1 g/cms). The dose distributions in the SRCTP (diameters of 6 cm [premature baby], 10 cm [neonates], and 14 cm [infants]) were evaluated. RFs were positioned every 5 mm along the radius at each SRCT-P, starting at center and ending on the surface. In this study, the absorbed dose and the dose distribution in the phantom were measured at 100 or 120 kV of the x-ray tube voltage. The other scanning parameters of the CT were 250 mA, 1.0 sec/rot, 1.25 x 8 mm slice thickness, and a 1.0 beam pitch. The mean center doses at 100 or 120 kV in 6, 10 and 14 cm of the SRCT-P were 37.0 or 64.2 mGy; 36.5 or 52.2 mGy; and 19.5 or 40.2 mGy, respectively. The mean surface doses in 100 or 120 kV at 6, 10 and 14 cm of the SRCTP were 33.9 or 57.9 mGy; 34.0 or 46.8 mGy; and 20.0 or 47.3 mGy, respectively. The absorbed dose was increased with a decrease in the phantom size. However, at 100 kV, the mean depth dose distributions at 6 or 10 cm of the SRCT-P were shown about the same value. The results indicated that the dose distribution in pediatric head CT becomes complex with patient head size and the tube voltage.
KW - computed tomography
KW - pediatric
KW - phantom
KW - radiation dosimetry
KW - radiochromic film
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U2 - 10.1007/978-3-642-23508-5_142
DO - 10.1007/978-3-642-23508-5_142
M3 - Article
AN - SCOPUS:80455128693
VL - 37
SP - 547
EP - 550
JO - IFMBE Proceedings
JF - IFMBE Proceedings
SN - 1680-0737
ER -