In the last 10 years, 3D and live 3D ultrasound — also called 4D ultrasound (3D/4D) — became popular in prenatal diagnosis
but focused mainly on the demonstration of the fetal face and other external fetal body parts (hands, feet, etc.). The use
of the 3D/4D in assessing the fetal heart evolved rapidly with the advent of the new technique called spatial and temporal
image correlation (STIC), which enabled acquisition of a volume data set with information pertaining to the beating fetal
heart [1, 2]. Matrix transducers for live 4D examination are already available, but the resolution is still too low to be routinely used
in fetal studies, and the expenses are still high.