ABSTRACT
Objective:In order to make up for the gap in the digital model of twins in the study of fetal radiation dosimetry, this study intends to construct a computational twins phantom based on low-dose CT images.Methods:The low-dose CT images of a pregnant patient were segmented by the combination of threshold automatic segmentation and manual segmentation, which were derived into stereolithography files. The maternal contour, fetal contour and bone structure were constructed using 3D modeling software, and the organ mass was adjusted according to the reference values of ICRP Publication 89 and WHO report after the organs were scaled on a specific scale.Results:The first set of Non-Uniform Rational B-Splines (NURBS) surface phantom of twins in China was established. The external contours, bones, size, position and posture of the phantom were completely consistent with those of the real human body. Each fetus had 25 organs or tissues. After optimization and adjustment, the relative deviation between the twin phantom and the reference value of organ mass was less than 10%.Conclusions:In this study, a personalized computational phantom of twins based on low-dose CT images is constructed, which fills the gap in the twin model. It is helpful in estimating the dose by the fetus from ionizing radiation received in the process of radiation diagnosis of pregnant women with twins.