Individual differences in medical radiation exposure in CT dosimetry based on age and BMI

Exposure settings should vary with patients to have an acceptable quality image with an appropriate patient dose. To manage medical exposure from computed tomography (CT), the size-specific dose estimates (SSDE) have been recommended to replace the volume computed tomography dose index because it considers patient size. However, organ dose is deemed more appropriate in the radiation protection field due to its correlation with radiation risk. In this presentation, the difference in medical radiation exposure in CT based on age and body mass index (BMI) by using the web-based CT dose calculator WAZA-ARIv2 and dosimetry system of radiophotoluminescence dosimeters (RGDs) and anthropomorphic phantoms will be introduced. In addition, the feasibility of BMI-based and age-based correction methods for organ dose estimation will also be investigated. For both BMI-based and age-based correction methods, the SSDE-associated correction factors showed consistency with the experimental results. Implementation of the SSDE-associated correction factors to the CT dosimetry systems is feasible, and organ dose estimation accuracy can be improved by applying these two correction methods.