Effects of multiple intravitreal injection on the stability of ocular surface and tear film by LipiView eye surface interferometer

Objective To observe the related indexes about dry eyes in patients with neovascular age-related macular degeneration (nAMD) after multiple intravitreal anti-vascular endothelial growth factor(VEGF) injections, so as to explore its effects on the stability of ocular surface and tear film. Methods The current study was a prospective randomized, double-blind,controlled clinical study. A total of 50 nAMD patients who underwent multiple intravitreal injection of anti-VEGF agents in the Affiliated Hospital of Xuzhou Medical University from January to March 2019 were enrolled. The tear film lipid layer thickness (LLT) was measured by the LipiView ocular surface interferometer before treatment and on each day after treatment for three days (indicated as V0, V1, V2, and V3, respectively). Meanwhile, lipid layer thickness (LLT), meibomian gland yielding secretion score (MGYSS), SPEED dry eye questionnaire score, tear breakup time (tBUT), corneal fluorescein staining, and Schimer I test were used to compare the differences in dry eye evaluation indicators between treated and control eyes at each follow-up time. Results At V0, there was no statistical difference in LLT, MGYSS, SPEED score, tBUT, corneal fluorescein staining, and Schimer I test results between treated and control eyes (P>0.05). With the increases in injection, the treated eyes presented remarkable decreases in LLT at V1, V2 and V3, decreases in MGYSS at V3, increases in SPEED score at V2 and V3, decreases in tBUT at V1, V2 and V3, as well as increases in corneal fluorescein staining at V2 and V3, compared with the control eyes (P<0.01). There was no statistical difference as to Schimer I test results between the treated and control eyes at each time point after treatment (P>0.05). Conclusions Multiple intravitreal injections can damage ocular surface microenvironment, weaken tear film stability, and cause clinical changes similar to evaporative dry eyes.