Serial Section Scanning Electron Microscopy of Adult Brain Tissue Using Focused Ion Beam Milling
... We present here an alternative sectioning approach using a focused ion beam (FIB) directed parallel to a block face for removing (or milling) thin layers of embedded tissue, and a scanning electron beam integrated into the same microscope for imaging this milled region (Heymann et al., 2006). We used this technology to serially image conventionally prepared adult brain tissue at a resolution that allowed us to follow the axons and dendrites in a volume of 286 μm3, and identify their synaptic connections. This milling approach can remove layers as thin as 15 nm from the block face. The study demonstrates the potential of this method for the automated collection of serial images through volumes of brain tissue that can be used for the analysis of neural connectivity.