Large-Volume Electron Microscopy

A large volume electron microscopy method was developed in association with serial electron microscopy technologies, which have improved quite significantly during the past two decades. These methods include focused ion beam (FIB)-scanning electron microscopy (SEM), serial block face (SBF)-SEM, automated tape-collecting ultramicrotome (ATUM)-SEM, and ATUM-transmission electron microscopy (TEM). Here, an outline of these imaging technologies and the latest advancements in ATUM-SEM and ATUM-TEM imaging are described. One of the distinguishing features of these approaches is the capability of large-volume EM imaging. This state-of-the-art technology enables the acquisition of data from one cubic millimeter or larger volumes of brain tissue for high-magnification electron micrographic and three-dimensional (3D) reconstruction of neural elements via AI-assisted automated segmentation, thereby allowing the analysis of synaptic connections in brain microcircuitry.