Intraocular Pressure Changes in Non-Glaucomatous Patients Receiving Intravitreal Anti-Vascular Endothelial Growth Factor Agents

PURPOSE: To study the prevalence of sustained intraocular pressure (IOP) elevation associated with intravitreal injection of anti-vascular endothelial growth factor (anti-VEGF) agents. METHODS: Prospective comparative study. Non-glaucomatous patients scheduled to receive intravitreal injection of anti-VEGF therapy were recruited from an outpatient eye clinic, Songklanagarind Hospital between April 2013 and March 2014. The IOP was measured by Goldmann applanation tonometer before and at 1 hour, 1 week, 1 month, 3 months, and 6 months after injection. The IOP was compared using the repeated measures analysis. Sustained IOP elevation was defined as either an IOP > 21 mmHg or an increase from baseline ≥ 5 mmHg on two consecutive visits. RESULTS: Seventy eyes of 54 patients met the inclusion criteria. The most common diagnosis was diabetic macular edema (48%). The mean IOP ± standard deviation (SD) before treatment was 13.7 ± 2.8 mmHg. The means ± SDs after treatment at 1 hour, 1 week, 1 month, 3 months, and 6 months were 11.3 ± 2.6, 13.7 ± 3.6, 14.1 ± 3.3, 14.0 ± 2.3, and 13.7 ± 2.4 mmHg, respectively. A mean of IOP difference at 1 hour postinjection and at baseline was -2.36 ± 2.5 mmHg (P < 0.001). Four of 70 treated eyes (5.7%) developed sustained IOP elevation (IOP ≥ 5 mmHg from baseline on two consecutive visits). The IOP returned to baseline levels after 1 month, in three eyes. One eye had sustained IOP elevation at 3 and 6 months follow-up. Thereafter, IOP returned to baseline level. There was no need of anti-glaucoma medication. CONCLUSIONS: After receiving intravitreal injection of anti-VEGF agent, a small proportion of non-glaucomatous eyes developed a sustained IOP elevation without requiring IOP-lowering treatment. At 1 hour postinjection, there was a significant reduction of the mean IOP compared with the baseline level.