Clinical Determinants of Dose–Length Product in Pediatric Brain CT: Implications for Age-Specific Imaging Protocols

Systematic optimization of pediatric brain computed tomography (CT) protocols remains challenging because clinical data are limited for children younger than 5 years. Sixty-nine non-contrast brain CT examinations in children aged 5 years or younger were retrospectively analyzed. Multiple linear regression was used to assess associations between dose–length product (DLP) and age group, sex, body mass index (BMI), and scanner group. In univariable analyses, DLP differed significantly by age group (p < 0.001) and scanner group (p < 0.001). In the multivariable model, only age group remained significantly associated with DLP; examinations in children aged 1–5 years showed an adjusted DLP increase of 158.71 mGy·cm compared with examinations in children younger than 1 year (p < 0.001). BMI and scanner group were not independently associated with DLP. Model stability was supported by residual normality and absence of multicollinearity. This study found that age group was the only measured variable significantly associated with DLP after adjustment, whereas BMI, sex, and scanner group were not significant. These findings highlight the importance of considering age when interpreting dose variation in pediatric brain CT.