A Study on the Reduction of Exposure Dose of Low-dose Chest CT using the Chest Phantom

Abstract

Increase of interest in well-being leads to increase the number of Low-dose chest CT for normal people. Regular health check-up as the national project targeting asymptomatic groups aims for the early diagnosis, so minimum dose is required for reducing any risk in radiologic tests. The dose and image quality were compared and analysed by applying various Scout kVp and scan parameters to the low-dose chest CT scan. In the application of scan parameters, the images with AEC and ASIR showed the higher signal to noise ratio, higher contrast to noise ratio and lower noise level than conventional low-dose chest CT images. The lowest dose was observed in the images of [Scout 140 kvp+LDCT+ASIR 50%+AEC], and the lowest noise and HU were observed in the image of [Scout 140 kvp+LDCT+ASIR 50%+AEC+detector coverage 20 mm]. In the respect of the dose and image quality, the protocol applying [Scout 140 kvp+LDCT+ASIR 50%+AEC] results lower radiation dose and improved image quality, which is the optimal protocol in comparison to conventional Low-dose chest CT.