Altered permeability of iris vessels following posterior chamber lens implantation: an electron microscopic study

Altered permeability of the iris vessels of monkey eyes following extra-capsular cataract extraction and posterior chamber intraocular lens implantation was studied by transmission electron microscopy using horseradish peroxidase (HRP) as a tracer. In control animals, HRP-reaction products were confined to the vascular lumens and to a small number of vesicles on the luminal side of the endothelial cells. In experimental animals, however, the interendothelial junctions of the iris vessels were filled with HRP-reaction products, and the endothelial cells of the iris vessels contained a large number of HRP-labeled plasmalemmal vesicles that opened into the basal lamina. HRP-reaction products were also found in the surrounding iris stroma of these experimental animals.