The observation of endothelial cells in vein grafts by the en face silver staining method

The introduction of en face silver staining to microsurgery has provided useful, detailed information about endothelial cells with regard to their size, shape, and number. With this staining method, endothelial cells of rat vein grafts have been morphologically investigated following division of the site of observation into three areas: the recipient artery, the proximal part of the vein graft, and the midportion of the vein graft. The results show that the arterial endothelial cells are small and spindle-shaped, whereas the cells in the proximal vein graft location are larger. Finally, large, rounded endothelial cells are seen in the midportion of the graft. These results are quantitated through a computerized graphic analysis system, which provides estimations of the cell size, Feret's diameters, and irregularities in the cell borders. The combination of en face silver staining and computerized graphic analysis has been especially useful for comparing minute changes that occur in recovering/regenerating endothelial cells.