Surface Tension and Aqueous Humor Outflow Dynamics

Abstract

Abstract: : Purpose: To measure and compare the surface tension of aqueous humor in patients with and without glaucoma. Methods: The surface tension of aqueous humor was measured using a commercially available instrument and software. The instrument was validated by measuring the surface tension of small quantities (0.1 cc) of known fluid (BSS) and that of rabbit aqueous and vitreous humor (20 rabbit eyes). The effect of glaucoma drugs on the surface tension of aqueous humor was studied in a rabbit model. 0.1–0.2 cc of aqueous humor was collected from the anterior chamber following paracentesis in humans during glaucoma and cataract surgery. Aqueous humor from 30 patients with glaucoma and 30 patients with cataracts but no glaucoma was studied so far. Results: The surface tension of rabbit aqueous humor measured to be 65.9 + 1.2 and that of the vitreous was 60.6 + 2.6. BSS surface tension measured was 70.7 + 0.9. Timolol and latanoprost did not alter the surface tension of aqueous humor in the rabbit model. The average surface tension of aqueous humor from glaucoma patients was 60.5 + 5.1 and in patients with only cataracts was 64.3 + 3.2. Conclusions: A technique of measuring the surface tension from small quantities of aqueous humor is validated. The role of surface tension of aqueous humor on the trabecular outflow pathways will be discussed. Supported by Tulane Glaucoma Research Fund

Keywords: aqueous