Abstract
The influence of intraocular pressure on resistance to aqueous outflow was evaluated in enucleated normal and glaucomatous human eyes by quantitative aqueous perfusion of the anterior chamber. When provision was made for free communication from anterior to posterior chamber to avoid artificial deepening of the anterior chamber, and the intraocular pressure was raised stepwise from 5 to 50 mm. Hg, the resistance to outflow progressively increased. The resistance to outflow increased more steeply in eyes with open-angle glaucoma than in non-glaucomatous eyes. When no communication was provided for flow of perfusion fluid from anterior to posterior chamber, and the pressure was raised in the same manner, the anterior chamber progressively deepened, but above 20 mm. Hg the resistance to outflow became nearly independent of intraocular pressure. Effects of reducing intraocular pressure, repeating perfusions, prolonging perfusions, and modifying the perfusion fluid were also evaluated. We postulate that intraocular pressure has direct influence on aqueous outflow channels. In open-angle glaucomatous eyes the aqueous outflow channels appear to be abnormally susceptible to this influence.