The risk of inducing cancer as a result of exposure to ionizing radiation is a cause for concern in medical imaging [1]. The number of CT procedures carried out has increased significantly over the last decade and reasons such as the need for cancer follow-up and increased use in trauma assessment have contributed to this. This brings into sharp focus the challenge of identifying methods to minimise radiation risk to patients whilst maintaining image quality at a level fit for the purpose of diagnosis [2]....

Using a Toshiba Aquilion 16 CT scanner an adult ATOM dosimetry phantom was exposed to a series of FTC and ATCM CT protocols: FTC - 100, 200, 250, 300 and 400mA; ATCM - low dose+, low dose, standard, quality and high quality, Three Pitch factors - 0.688, 0.938 & 1.438 and three detector configuration of 0.5×16mm, 1.0×16mm and 2.0×16mm. For all acquisition protocols, tube voltage was fixed at 120 kVp and a 0.5 second tube rotation. Estimations of ER were undertaken using Metal Oxide Semiconductor...

Data was analysed using SPSS (22.0) and Excel (2013). Tests for normality were conducted using the Shapiro-Wilk test. A paired samples t–test was conducted; this was performed to compare the mean ER between FTC and the corrected ATCM and the mean ER between FTC and the uncorrected ATCM. The uncorrected ATCM data has been included to enable clinically relevant comparisons to be made between FTC and ATCM approaches, whilst the corrected ATCM data has been included to enable fair comparison of dose and risk data...

This is the first study to compare adult effective lifetime risk of radiation-induced cancer (ER) for FTC and ATCM abdominal CT examinations. Phantom results demonstrated reduced mean ER when using FTC at 300mA and pitch factors >1 when compare with mean ER corrected ATCM data. However, the mean ER for the uncorrected ATCM data was higher than FTC (female ~17% and male ~ 23%) for all ages and both genders .This method can be used to compare ER for abdominal CT scans within clinical practice.

[1] Desouky, Omar, Nan Ding, and Guangming Zhou. "Targeted and non-targeted effects of ionizing radiation." Journal of Radiation Research and Applied Sciences 8, no. 2 (2015): 247-254. [2] Brenner, D. J. "Slowing the increase in the population dose resulting from CT scans." Radiat Res. (2010); 174(6): 809-815 [3] Venkat, Hamsa, Marissa Rollnick, John Loughran, and Mike Askew,eds. Exploring Mathematics and Science Teachers’ Knowledge: Windows Into Teacher Thinking. Routledge, 2014. [4] Tootell, A. K., Szczepura, K. R., & Hogg, P. Optimising the number of thermoluminescent dosimeters...