Optimizing image quality and minimizing radiation dose in pediatric abdominal multiphase contrast-enhanced computed tomography: a study on CARE kV and CARE Dose 4D.

Background: Multiphase contrast-enhanced computed tomography (CECT) is a commonly used modality in pediatric computed tomography (CT) scans. However, the purposes and focus of each phase, such as CT angiography (CTA), and parenchymal phase, are different. In routine practice, the same scanning parameters are used for all phases, resulting in unnecessary radiation exposure for children. Accurately and rapidly adjusting the scanning parameters for each phase of CECT is challenging in clinical settings. This retrospective cross-sectional study was designed to investigate the feasibility of using both CARE kV and CARE Dose 4D to reduce the radiation dose while maintaining diagnostic quality in multiphase CECT scans of children. Methods: Overall, 57 children (33 males and 24 females) who underwent multiphase abdominal CECT in Xinjiang Hospital of Beijing Children's Hospital with an average age of 6.52±4.30 years (range, 0.1-15 years), were enrolled. The tube voltage was automatically modulated using CARE kV. The tube current was automatically modulated using CARE Dose 4D. Different dose saving optimization indices (DI) were used for the three phases: a DI value of 3 was used for the unenhanced CT phase, a DI value of 12 was used for the CTA phase, and a DI value of 7 was used for the parenchymal phase. The tube voltage and volume CT dose index (CTDI Results: The most selected tube voltage in the unenhanced CT, CTA, and parenchymal phases was 100 kV (49/57, 85.96%), 70 kV (36/57, 63.16%), and 80 kV (32/57, 56.14%), respectively. The differences between the three phases were statistically significant (P<0.001). The CTDI Conclusions: The combined use of CARE Dose 4D and CARE kV could effectively reduce the radiation dose in children during multiphase abdominal CECT without compromising the diagnostic image quality.