The fate of anterior chamber flurescein in the monkey eye. 1. The anterior chamber outflow pathways.

As defined by freeze-dry tissue techniques, there are two distinct routes by which fluorescein leaves the anterior chamber of the living rhesus monkey eye. I. The conventional pathway: Within five minutes of the initiation of fluorescein perfusion through the anterior chamber, the conventional pathway filled. Tracer passed through the trabecular meshwork into Schlemm's canal, and flowed back within scleral and episcleral venous derivatives to enter large veins in the extraocular muscles. II. The uveo-vortex pathway: Fluorescein rapidly moved into the iris stroma and into the anterior part of the ciliary body. The anterior chamber border of the ciliary body is little more than a sparse mesh from which fluorescein entered directly into the substance of the anterior ciliary muscle. Fluorescein penetrated blood vessels in the iris stroma and in the anterior ciliary body from where it could be traced posteriorly to the equatorial choroid and vortex veins. The specific sequential tissue distribution of fluorescein strongly supports the existence of a uveo-vortex pathway for aqueous outflow.