Collaborating with imaging physicists at Duke's Center for In-vivo Microscopy, Smith established protocols for using magnetic resonance imaging (MRI) to track differences in embryonic development between normal animals and mutant or gentically-manipulated embryos. These are some of the first MRI's ever produced of mammalian embryos.

The National Institute of Child Health and Human Development funded Smith's work to generate an image database of human embryos from 2 to 8 weeks old based on magnetic resonance microscopy. The Human Embryo Website created for this work includes individual MRI slice images, three-dimensional images, animations, stereo-pair animations, animations of organ systems, and photo-micrographs.

Smith developed MRI contrast materials and infusion methods to study heart and blood vessel development in normal and genetically-engineered mouse, rat, and chick embryos. These methods have subsequently become the standard protocols for magnetic resonance imaging of cardiovascular development in embryos.

These images are from the first published reports of in-utero and in-vitro imaging of mammalian embryos. In-utero: live embryos in the uterus; In-vitro: live embryos explanted from the uterus to a culture chamber.