Short-Term Visual Acuity and Intraocular Pressure Changes and Their Correlation after Anti-Vascular Endothelial Growth Factor Injection

Purpose: To assess the effect of intravitreal anti-vascular endothelial growth factor injection on short-term changes in intraocular pressure (IOP) and visual acuity (VA) and the correlation between the two values. Methods: This study included 25 eyes of 25 patients undergoing intravitreal injection of bevacizumab (IVB) with preinjection uncorrected VA (UCVA) >20/40. IOP and UCVA were measured before injection and 1, 5, 10, 15, 20, 25, and 30 min after injection, using a Tono-Pen (Reichert, Chicago, Ill., USA). The IOP and VA values before and after injection were compared. The correlation between IOP and VA at each time point was analyzed. Results: The preinjection IOP value (17.7 mm Hg) increased sharply to 43.1 mm Hg 1 min after injection, followed by a decrease to 30.4, 24.6, 20.7, 18.7, 18.2, and 17.7 mm Hg at 5, 10, 15, 20, 25, and 30 min, respectively. The preinjection UCVA value (0.21; logMAR) increased to 0.96 one minute after injection, followed by a decrease to 0.61, 0.44, 0.33, 0.27, 0.23, and 0.22 at 5, 10, 15, 20, 25, and 30 min, respectively. Significant differences were evident between the preinjection IOP and VA values and those observed over the 5- to 25-min period after injection (p < 0.05). The correlation between IOP and VA was significant 1, 5, and 10 min after injection [p < 0.001 (1 min), p = 0.033 (5 min), and p = 0.002 (10 min)]. Conclusions: Differences in all IOP and VA values were significant up to 25 min after IVB, compared with preinjection values; however, no significant difference was found 30 min after injection. Such fluctuations in VA and IOP were positively correlated. The patients' own knowledge of VA fluctuations after injection may provide ophthalmologists with sufficient evidence to make an indirect clinical judgment regarding short-term complications of intravitreal injection.