CTDI_vol: A suitable normalization for CT dose conversion coefficients at different tube voltages?

Reliable estimates for patient doses for CT examinations are desirable for the patients themselves as well as for new epidemiological studies. It has been shown that dose conversion coefficients normalized to CTDIvol provide rather scanner independent quantities. In this work, it is demonstrated that this normalization provides also tube voltage independent values by simulating axial CT scans of a seven-year old infant and an adult. The differences in the effective dose conversion coefficients per CTDIvol between 80 and 120 kV is for most body heights below 5%. Only at the height of the testes and the thyroid the difference can be as large as 15%. This results in differences of the effective dose conversion coefficient per CTDIvol between 80 and 120 kV of less than 6-7% for typical CT examinations