title: Comparison of air kerma between C-arm CT and 64-multidetector-row CT using a phantom.
abstract: OBJECTIVE
  To compare air kerma after scanning a phantom with C-arm CT and with 64-multidetector row CT (64MDCT).
  
  
  METHODS
  A phantom was scanned using parameters based on data of ten patients with hepatocellular carcinoma who had C-arm CT during hepatic arteriography and 64MDCT during arterial portography. Radiation monitors were used to measure air kerma ten times at each of five points: the center (A), top (B), left side (C), bottom (D), and right side (E).
  
  
  RESULTS
  For C-arm CT vs. 64MDCT, air kerma after scanning was 10.5 ± 0.2 vs. 6.4 ± 0.0 for A, 1.5 ± 0.0 vs. 11.6 ± 0.2 for B, 37.1 ± 0.2 vs. 11.1 ± 0.1 for C, 55.6 ± 1.0 vs. 10.6 ± 0.1 for D, and 40.5 ± 0.5 vs. 11.7 ± 0.1 for E, respectively. Air kerma for A, B, C, D, and E was 1.64, 0.13, 3.34, 5.24, and 3.46 times greater for C-arm CT than for 64MDCT, respectively.
  
  
  CONCLUSIONS
  Using the same scanning parameters as for clinical cases, air kerma values were greater with C-arm CT than with 64MDCT; at the dorsal side of the phantom, they were 5.24 times greater with C-arm CT compared with 64MDCT.
authors.affiliation: Department of Radiology, Wakayama Medical University, 811-1 Kimiidera, Wakayamashi, Wakayama, 641-8510, Japan.
authors.forename: Seiki
authors.initials: S
authors.lastname: Hosokawa
authors.forename: Nobuyuki
authors.initials: N
authors.lastname: Kawai
authors.forename: Morio
authors.initials: M
authors.lastname: Sato
authors.forename: Hiroki
authors.initials: H
authors.lastname: Minamiguchi
authors.forename: Motoki
authors.initials: M
authors.lastname: Nakai
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Murotani
authors.forename: Tadayoshi
authors.initials: T
authors.lastname: Nishioku
authors.forename: Shintaro
authors.initials: S
authors.lastname: Shirai
authors.forename: Tetsuo
authors.initials: T
authors.lastname: Sonomura
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D006528:Carcinoma, Hepatocellular / Q000000981:diagnostic imaging; D005260:Female; D006801:Humans; D008113:Liver Neoplasms / Q000000981:diagnostic imaging; D008297:Male; D061330:Multidetector Computed Tomography / Q000379:methods; D019047:Phantoms, Imaging; D011829:Radiation Dosage; D011874:Radiometry; D014057:Tomography, X-Ray Computed / Q000379:methods*