OUTFLOW FACILITY AND MORPHOLOGY AFTER VISCOCANALOSTOMY IN RHESUS MONKEYS

Paul L. Kaufman1, Daniel M. Albert1, Ernst R. Tamm2 and           Roberto Carassa3

1University of Wisconin, Madison, USA, 2University of Erlangen-Nurnberg, Germany and 3University of  Milano, Italy

Introduction: Viscocanalostomy (V) is an alternative to trabeculectomy in

some glaucoma patients.  To better understand effects of V on outflow

facility (OF) and morphology, these parameters were evaluated in six rhesus monkeys, two of which were glaucomatous in both eyes.  Methods: Two monkeys had experimentally induced glaucoma in both eyes for at least 2 months following argon laser scarification of the trabecular meshwork. OF was measured by two-level constant pressure perfusion and tonography in 4 of the 6 monkeys, including the glaucomatous ones.  V was then performed in one eye of each of 5 monkeys and both eyes of one monkey 4-6 weeks after OF measurements. OF was measured by tonography again approximately 4 weeks after V in 3 monkeys, which were then sacrificed for light microscopy. 4-6 weeks after OF measurement by constant pressure perfusion, the remaining 3 monkeys were sacrificed for electron microscopy following perfusion of gold

tracer through the anterior chamber. Intraocular pressure (Goldman

applanation and Tono-Pen tonometry), ocular biomicroscopy, fundus

photography and scanning laser ophthalmolscopy were monitored periodically from the initiation of the study. Results: This abstract was submitted upon request of the meeting organizer, with the knowledge that few data were available at the time of submission.  V produced no change in intraocular pressure in glaucoma and control monkey eyes.   Conclusion: V can be successfully performed in rhesus monkeys.  Morphological and OF results are pending.