“…Since the onset of the use of corrosion casting in medical research, only two-dimensional~2D! data could be acquired from corrosion casts by means of scanning electron microscopy~Kurokawa & Ogata, 1980;Nakamura & Masuda, 1981;Zhang, 1987;Giuvarasteanu, 2007;Rossi-Schneider et al, 2008;Bereza et al, 2012aBereza et al, , 2012bWalocha et al, 2012!. Recently, 3D image data from corrosion casts were obtained by means of micro-CT and nano- CT scan-ning~Mondy et al, 2009a;Wagner et al, 2011!. In order to visualize vessels in intact tissues using micro-CT, either the luminal structures of interest can be filled with radiopaque material before scanning~Ritman, 2004; Almajdub et al, 2008;de Kemp et al, 2010;Razavi et al, 2012!, or alternatively a negative view can be obtained by impregnating the surrounding tissues with osmium te-troxide~OsO 4 !, which is a secondary transmission electron microscopy fixative~Ritman, 2004; Ananda et al, 2006!. However, these approaches yield qualitatively poor images of a tissue 's microvasculature~Mondy et al, 2009b;Vandeghinste et al, 2011!. Many radiopaque metal powders are, unfortunately, not soluble in Batson's #17.…”