Abstract
Purpose:
The purpose of this project was to develop a model of glaucoma via surgical induction of increased intraocular pressure (IOP) in Yucatan miniature swine.
Methods:
Three pigs (two female, one male) had bilateral IOP measurements performed prior to surgical intervention to establish a baseline IOP for each animal from which future changes in IOP could be identified. IOP measurements (mm Hg) were taken with a Tonopen Vet Tonometer. In order to reduce venous drainage from the eyes, episcleral veins were scarified by cauterization in each eye. IOPs were periodically measured for several weeks post-cauterization surgery. Pharmacologic intervention was then instituted with a commercially available synthetic prostamide analog with ocular hypotensive activity. Drops were applied once daily, and IOPs continued to be measured. After 7 weeks of daily treatment, eye drops were discontinued, and IOP measurements continued to be obtained.
Results:
All animals presented with significant increases in IOP measurements post surgical intervention and significant decreases in IOP with pharmacological therapy. Statistical tests included sample mean comparison by 2-tail T-test P-value (T≤t). Data by phase as follows-Mean±SD (N readings), P-value: Baseline:19±4 (65); Post-Surgery: 24±5 (124), ≤0.005 (Baseline vs. Post-Surg); Treatment: 18±4 (75), ≤0.0006 (Post-Surg vs Treatment) Recovery: 20±4 (80), ≤0.006 (Treatment vs Recovery).
Conclusions:
Therefore, the Yucatan miniature swine should be considered a viable model for surgically induced glaucoma. The miniature swine eye is also responsive to pharmacological therapy to reduce IOP and as such could be a potential model for future pharmacological research.
Keywords: 568 intraocular pressure •
420 anterior chamber •
749 vascular occlusion/vascular occlusive disease