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Jpn J Radiol (2014) 32:302307 DOI 10.1007/s11604-014-0297-x
TECHNICAL NOTE
Comparison of air kerma between C-arm CT and 64-multidetector-row CT using a phantom
Seiki Hosokawa Nobuyuki Kawai Morio Sato
Hiroki Minamiguchi Motoki Nakai Kazuhiro Murotani
Tadayoshi Nishioku Shintaro Shirai Tetsuo Sonomura
Received: 16 April 2013 / Accepted: 9 February 2014 / Published online: 20 February 2014 Japan Radiological Society 2014
AbstractPurpose To compare air kerma after scanning a phantom with C-arm CT and with 64-multidetector row CT (64MDCT).
Materials and 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 ve 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.
Conclusion 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.
Keywords Air kerma C-arm CT Cone-beam CT
Multidetector row CT
Introduction
When transcatheter arterial chemoembolization (TACE) is conducted for patients with hepatocellular carcinoma (HCC), CT during hepatic arteriography (CTHA) and CT during arterial portography (CTAP) are performed using either C-arm CT or multidetector row CT (MDCT) [15]. These scanners are also used to check the distribution of lipiodol accumulation in tumors treated by TACE with lipiodol [6, 7]. Our institute is equipped with a hybrid CT and angiography facility that also has a C-arm CT unit. Radiologists are becoming increasingly concerned with radiation exposure to patients during these procedures [8 10]. Comparison data exist for image noise, spatial resolution, and low-contrast resolution between C-arm CT and MDCT, but not for radiation exposure (C/kg) based on scanning parameters used for clinical cases...