Validation of a novel 3D-printed anthropomorphic pediatric abdomen phantom using photon-counting CT

This study compares objective and subjective image quality (IQ) between a pediatric patient's CT scan and a subsequently 3D-printed anthropomorphic abdomen CT phantom on a photon-counting CT (PCCT). We used a dedicated 3D-printed CT phantom based on DICOM data obtained from a PCCT scan of a 5-year-old boy (70 kV, 458 mAs). We performed two scans on the phantom (1: 70 kV, 461 mAs and 2: 90 kV, 148 mAs), reconstructing them with three kernels. We measured the objective IQ based on mean CT values and image noise within eight target structures. Three radiology experts assessed the subjective IQ on a 5-point Likert scale. The CT values of organs and vessels in phantom scan 1 (Br40) were equivalent to those in the patient (p = 0.019). The phantom demonstrated higher mean CT values for fat and lower CT values for bone. The image noise was equivalent between both scans (p = 0.027). The phantom showed high subjective IQ but a significantly lower rating than the patient (median 4 vs. 5, p < 0.001). In conclusion, this study demonstrates comparable IQ between the phantom and the patient scan at comparable dose parameters. In the future, it may be possible to anticipate radiation exposure in dose reduction studies.