Figures 1, 2. (1) Schematic illustrates the profile of radiation dose delivered during a single CT scan. The CTDI equals the shaded area under the curve divided by the section thickness (T). (2) Schematic illustrates the profile of radiation dose delivered during multiple CT scans. T represents section thickness, and I represents the interval between sections. The MSAD includes the contributions of neighboring sections to the dose of the section of interest.