EFFECTIVE DOSE AND EFFECT OF DOSE MODULATION FOR LOCALIZER RADIOGRAPHS USING APPLIED AND ALTERNATIVE SETTINGS ON TOSHIBA/CANON CT SYSTEMS

Abstract The purpose was to estimate the effective dose of Toshiba/Canon thorax localizer radiographs for available parameter settings, and to test their dose modulation ability. Localizer radiographs were acquired of anthropomorphic chest phantoms (body mass indices 29 and 23) using various settings (120–80 kV, 100–10 mA). The milliamperes values were compared from resulting helical scan data. Effective dose was computed for two computed tomography (CT) scanners (Aquilion Prime and One Genesis) using a Monte Carlo-based software. For the smaller phantom, all curves were superimposed. For the larger phantom, most curves were also superimposed, except for the one generated from the lowest parameters. The Aquilion Prime system yielded an effective dose of 0.40/0.56 mSv (male/female) using the default parameters. The localizer radiograph dose could be reduced by >90% without affecting the dose modulation. The dose was further reduced by 30–50% in the One Genesis CT system due to improved beam filtration.