Scanning Electron Microscopy and Micro-Computed Tomography Imaging of the Utero- and Fetoplacental Circulations

Chapter Summary Scanning electron microscopy (SEM) and three-dimensional (3D) micro-computed tomography (micro-CT) are high-resolution imaging techniques that can be used to visualize the structure of the uteroplacental and fetoplacental circulations. In both cases, a cast of the 3D circulatory structure is made by perfusion of a liquid agent through the circulatory bed, which solidifies prior to imaging. SEM images of casts with tissue removed reveal the topology of all vessels, including the smallest vessels in the microcirculation. X-ray imaging of casts with tissue intact can be used to create micro-CT datasets for 3D images, as well as quantitative measurements of individual vessels or of the entire 3D bed. Micro-CT has a lower image resolution, which may limit examination of the microcirculation. Thus SEM, with its higher resolution, is an important complementary method to employ.