Changes in Scleral Thickness Following Repeated Anti-vascular Endothelial Growth Factor Injections.

PURPOSE

This cross-sectional study aimed to compare changes in scleral thickness between eyes injected with repeated anti-vascular endothelial growth factor (anti-VEGF) drugs and fellow injection naive eyes using optical coherence tomography (OCT).

METHODS

A total of 79 patients treated with three intravitreal anti-VEGF injections in one eye versus no injections in the fellow eye were included.Anterior segment-OCT measured scleral thickness in the inferotemporal quadrant 4 mm away from the limbus.

RESULTS

Injected eyes had a mean scleral thickness of 588 95 μm versus 618 85 μm in fellow naïve eyes ( 0.001). Comparing injected eyes to fellow naïve eyes stratified by injection number showed a mean scleral thickness of 585 93 μm versus 615 83 μm in eyes with 3-10 injections ( = 32, = 0.042); 606 90 μm versus 636 79 μm in eyes with 11-20 injections ( = 24, = 0.017); and 573 104 μm versus 604 93 μm in eyes with 20 injections ( = 23, = 0.041). There was no significant correlation between injection number and scleral thickness change ( = -0.07, = 0.26). When stratified by indication, subjects with retinal vein occlusions showed a statistically significant difference in scleral thickness between injected and fellow naïve eyes (535 94 μm and 598 101 μm, respectively, = 0.001).

CONCLUSION

Compared to injection naive eyes,multiple intravitreal injections at the repeated scleral quadrant results in scleral thinning. Consideration of multiple injection sites should be considered to avoid these changes.