Application of Poiseuille's Law to Aqueous Outflow

Abstract

Since the perfusion rate of an enucleated eye is very near that of the perfusion rate in vivo,^1,2it is reasonable to infer that nervous or "life" forces are not a constant influence on this in vivo rate and that the outflow is governed primarily by physical laws of flow. It is important, therefore, to ascertain the quantitative expression of the physical factors which govern the outflow rate. Poiseuille's law, ordinarily considered as dealing with viscosity of solutions, is actually an expression of the fundamental law governing laminar flow of liquids through cylindrical tubes. The application of any physical law to biological processes must be done with great caution and with due respect to the limitation inherent both in the law itself and in biological systems. In general, investigators³are more inclined to apply this law to aqueous outflow than to blood flow because the aqueous is a