Three- and four-dimensional HDlive rendering images of normal and abnormal fetuses: pictorial essay

Background Our objective is to present our experience of normal embryonic development and fetal anatomy and fetal anomalies reconstructed employing the three-dimensional (3D) and four-dimensional (4D) HDlive rendering mode. Methods A total of 18 normal embryos and fetuses and 21 abnormal fetuses (one case each of thoracic meningocele, thickened nuchal translucency, multicystic dysplastic kidney, gastroschisis, omphalocele, and ovarian cyst, five of hydrops fetalis, three of skeletal abnormality, three of chromosome abnormality, two of cystic hygroma, and two of amniotic band syndrome) at 7-36 weeks' gestation were studied using the 3D/4D HDlive rendering mode. Results In normal fetuses, marked embryonic development with advancing gestation was clearly shown in the first trimester of pregnancy, and various realistic facial expressions were noted in the second and third trimesters. In abnormal fetuses, anatomically realistic features such as gross specimens were obtained. In particular, 3D/4D HDlive provides new, realistic sensations for the diagnosis of amniotic band syndrome, skeletal abnormalities, and facial abnormalities. Conclusion 3D/4D HDlive rendering images seem to be more readily discernible than those obtained by conventional 3D/4D sonography. 3D/4D HDlive may be an important modality in future embryonic research, fetal neurobehavioral assessment, and the evaluation of fetal anomalies.