Structural change following glaucoma surgery. I. Mapping the aqueous outflow pathways in the normal rabbit eye

Glaucoma procedures tend to induce ocular hypotony. Seeking to determine the aqueous outflow pathway, we investigated casting the outflow network by in vivo injection of a polymer in the anterior chamber. Poly(methyl methacrylate) (PMMA) casts of cilioscleral sinus and aqueous veins were made by injecting a mixture of methyl methacrylate, initiator, promoter and blue ink, through the limbus, in the anterior chamber of a anesthetized rabbit. The transfer of PMMA from the cilioscleral sinus of the rabbit eye to the aqueous veins was shown. The anterior chamber and the cilioscleral sinus casts were colored in blue but the aqueous veins casts were transparent due to the filtering effect of the Meshwork discriminating the ink penetration in the aqueous veins. This technique will be useful to help understanding the role-played by the aqueous veins after glaucoma surgery, or after implantation of devices designed to reduce intraocular pressure.