Inflammatory Reaction After Aflibercept Intravitreal Injections Associated With Silicone Oil Droplets Released From Syringes: A Case-Control Study

BACKGROUND AND OBJECTIVE: To determine factors causing inflammation after intravitreal aflibercept injections. PATIENTS AND METHODS: This case-control study included aflibercept-treated eyes with inflammation post-injection and aflibercept-treated control eyes. Medical records were analyzed to identify contributing factors. Biophysical tests were performed to characterize properties of particle aggregation. Institutional review board approval was obtained. RESULTS: Inflammation developed in six eyes; three patients had anterior uveitis, and five had vitreous cells. Oil droplets were seen in all cases. Saldanha Rodrigues (SR) syringes were used in all cases. Among controls, SR and Becton-Dickinson syringes were used in 10 and 17 eyes, respectively. Regression analysis showed an association between SR syringes and inflammation (odds ratio = 21.66; 95% confidence interval, 1.10–425.06; P = .043). Biophysical analyses primarily showed aggregation possibly from free oil droplets or protein-oil droplet aggregation. CONCLUSIONS: Post-injection inflammation was associated with SR syringes. Silicone oil droplets, especially after syringe agitation, might play a role in the inflammatory reaction. [ Ophthalmic Surg Lasers Imaging Retina . 2019;50:288–294.]