A scanning electron microscopy study of the endothelial folds in normal and anastomosed common carotid arteries in albino rats.

The results of this scanning electron microscopy study show that the endothelial folds of the common carotid arteries of rats are composed of rows of 2 or 3 endothelial cells standing alongside one another on the underlying internal elastic lamina. If anastomosed arteries develop a stenosis the endothelial folds, instead of running longitudinally along the vessels, are rotated through 90 degrees to run transversely. The most important factor causing this change in direction of the endothelial folds is fibrosis of the arterial wall following damage to the blood supply of the vessel during dissection and anastomosis.