Imaging of the human embryo with magnetic resonance imaging microscopy and high-resolution transvaginal 3-dimensional sonography: human embryology in the 21st century.

Objective: This article illustrates early human development, demonstrated by magnetic resonance (MR) microscopy and computer graphics on human embryo specimens, and advanced 3-dimensional (3D) sonography in clinical obstetrics.

Study Design: Fixed human embryo specimens were imaged by MR microscopy coupled with computer graphics technology. Transvaginal 3D sonography was used to examine embryos in ongoing gestations and compare embryological findings.

Results: Advances in MR microscopy allowed detailed visualization of embryo specimens. Computational techniques allowed reconstruction of tomographic images to render them as 3D structures. High-resolution transvaginal 3D sonography produced images that demonstrated the neural tube from week 6; brain anatomy and vasculature from week 8; and craniofacial morphology and other structures from week 11.

Conclusion: MR microscopy is a novel technique that enables nondestructive, high-resolution imaging of embryo specimens. On the other hand, 3D sonoembryology allows detailed anatomical visualization in vivo and is the basis for the assessment of anomalies as well as human development.