The Role of Corneal Hysteresis in Predicting Outcomes in Glaucoma Patients Undergoing Trabecular Microbypass Stent in Combination with Cataract Surgery.

ABSTRACT

INTRODUCTION: Trabecular microbypass stents are effective at lowering intraocular pressure in patients with mild to moderate glaucoma. Corneal hysteresis has been shown to correlate with reduction in intraocular pressure in patients using topical prostaglandin analogues and selective laser trabeculoplasty to treat glaucoma. The purpose of this study was to investigate whether baseline corneal hysteresis measurements were predictive of effectiveness of trabecular microbypass stents in treating glaucoma. METHODS: This was a retrospective chart review of 163 eyes from 109 patients with primary open angle glaucoma that underwent simultaneous trabecular microbypass stenting and cataract surgery. This was a single center study with one surgeon performing all procedures. RESULTS: The eyes were grouped into quartiles according to baseline corneal hysteresis measurements. Baseline intraocular pressures among the four quartiles of baseline corneal hysteresis groups were similar (p=0.082, ANOVA). The average intraocular pressure reduction at 3 months post-operative visits were 3.67, 1.51, 2.83, and 2.09 mmHg for the first through fourth quartiles respectively, and these differences are insignificant overall (p=0.34, ANOVA). Likewise, no significant difference was detected in terms of reduction in glaucoma medications among the quartiles three months after surgery (p=0.78, ANOVA). CONCLUSION: Baseline corneal hysteresis does not appear to show any value in predicting intraocular pressure reduction in response to placement of a trabecular microbypass stent for treating glaucoma.