The pressure and volume dependence of the rate of wash-out in the bovine eye

The rate of increase of outflow facility (the wash-out rate) was measured in bovine eyes at 6 and 15 mm Hg. The time-rate-of-change of facility was less at 6 mm Hg (0.20: delta facility/hour) than at 15 mm Hg (0.44). However, when the data was analyzed as a function of volume passing through the outflow system, the volume-rate-of-change of facility was the same at 6 (0.35: delta facility/ml) and 15 mm Hg (0.34). This was consistent with the hypothesis of macromolecules "washing-out" of the aqueous outflow system, if these macromolecules were saturable in the perfusate.