The Effect of Prophylactic IOP-Lowering Medication after Intravitreal Dexamethasone Implantation

ABSTRACT

PURPOSE: To investigate the effect of prophylactic intraocular pressure (IOP)-lowering medication after intravitreal dexamethasone implantation. METHODS: This is a retrospective analysis of 39 eyes undergoing intravitreal dexamethasone implantation for macular edema. Eyes were divided into two groups, those which had used prophylactic IOP-lowering medication and those which had not. IOP was measured preoperatively, at one week, and monthly until six months post-injection in each group. RESULTS: The mean pre-injection IOP for the group that had not used prophylactic IOP-lowering medication and the group that had was 13.95 +/- 3.32 mm Hg and 13.56 +/- 3.71 mm Hg, the mean post-injection IOP at two months was 15.81 +/- 3.75 mm Hg and 12.56 +/- 5.02 mm Hg, and that at six months was 12.90 +/- 2.95 mm Hg and 11.44 +/- 3.59 mm Hg, respectively. The difference between the two groups was statistically significant at one week, one month, two months, and three months (p = 0.001, 0.002, 0.011, 0.035, respectively). A greater than 22 mm Hg increase in IOP was seen in four eyes (19.05%) in the group that had not used IOP-lowering medication and in one eye (5.56%) in the group that had. A greater than 5 mm Hg increase in IOP from baseline was seen in eight eyes (38.10%) in the group that had not used IOP-lowering medication and in one eye (5.56%) in the group that had. CONCLUSIONS: After intravitreal dexamethasone implantation, prophylactic IOP-lowering medication will significantly prevent IOP increase and decrease the number of patients requiring additional treatment that could cause potential damage to the retina and optic nerve.