Abstract
PURPOSE: To evaluate the relationship between the pain severity and the injection speed, anxiety, and intraocular pressure changes during the intravitreal injection (IVI) of anti-vascular endothelial growth factor (anti-VEGF) agents. METHODS: The 84 eyes were prospectively registered in the study. The severity of the pain was evaluated with the visual analogue scale (VAS). The severity of the anxiety was measured with the Beck Anxiety Inventory. All patients were naive to IVI. Bevacizumab or Ranibizumab 0.05 mL was administered intravitreally. The intraocular pressure (IOP) was measured before and after the procedure. RESULTS: Correlation analyses were performed between VAS and the injection speed, the IOP difference, and anxiety. There was a negative significant correlation between injection speed and VAS (p = 0.024 r=-246). There was a positive significant correlation between the IOP difference and VAS (p = 0.001, r = 0.365). In addition, there was strong positive correlation between the anxiety level and VAS (p˂0.001 r = 0.77). Linear stepwise regression analysis was used to determine which of these three independent variables (VAS, IOP difference, Anxiety) influenced pain the most, and Anxiety and IOP difference were found to affect the dependent variable of VAS more. There was no significant difference between the IOP difference (p > 0.05) and anxiety scale values (p > 0.05) between the two anti-VEGF agents while there was statistically significantly more pain felt during the Bevacizumab IVI (p = 0.005). CONCLUSIONS: The parameter with the most influence on pain severity was anxiety in this study, followed by the postop-preop IOP difference. There was also a significant negative correlation between injection speed and VAS.