Size-specific dose estimation in pediatric computed tomography: From dose characterization to individualized optimization

Table 2 Comparison of computed tomography size-specific dose estimate body type parameters in pediatric

Body size parameters	Data sources	Advantage	Limitations	Localization in pediatric CT
Age	Clinical data	Most readily available and convenient for initial protocol screening	Significant differences in body size among the same age pediatrics	Rough stratification variable
Weight	Clinical data	Available before scanning, related to body size	Does not reflect cross-sectional attenuation or organ distribution	Practical variable for protocol stratification
AP/LAT	CT topogram or cross-sectional image	Simple to measure and suitable for use with the TG-204	Influenced by slice and direction, it does not reflect organizational composition.	Basic geometric dimension specifications
Deff	AP and LAT geometric mean	Highly standardized, easy to promote	Differences in chest and body composition may result in potential biases	Common Metrics for Traditional SSDE
Dw	CT image area + CT value	Simultaneously reflecting size and attenuation	Requires reliable segmentation and validation across scanners, protocols, and body regions	Recommended indicators for the future
Automatic size segmentation	Image algorithms	High throughput, reproducible, suitable for quality control	Need to verify cross device generalization	Development direction of dose management system

TG-204: Task Group 204; CT: Computed tomography; AP: Anteroposterior; LAT: Lateral; D_eff: Effective diameter; SSDE: Size-specific dose estimate; D_w: Water-equivalent diameter.