Multiple Anti-Vascular Endothelial Growth Factor Injections May Cause Scleral Thinning

Multiple intravitreal injections in the same scleral quadrant may result in scleral thinning, according to a study published in the Journal of Ophthalmic and Vision Research. 

Investigators included 79 patients (mean age 73 years, 49 women, mean number of injections 16.31±13.1) treated with at least 3 anti-VEGF injections in one eye and no injections in the contralateral eye. They obtained anterior segment OCT measurements of scleral thickness in the inferotemporal quadrant at a distance of 4 mm from the limbus. 

The researchers observed thinner mean scleral thicknesses in eyes receiving anti-VEGF injections compared with those that did not receive them (588±95 µm vs 618±85 µm; P <.001). However, they observed no association between the number of injections and degree of scleral-thickness change (r = –0.07; P =.26). After stratifying by indication, the team determined that patients with retinal vein occlusion exhibited a significant difference in scleral thickness between injected and control eyes (535±94 µm vs 588±101 µm; P =.001).

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

Study limitations include a small sample size, cross-sectional design, and use of the contralateral eye instead of measurements obtained before anti-VEGF injections as a control. 

Reference

Wang Y, Sim W, Wang P, et al. Changes in scleral thickness following repeated anti-vascular endothelial growth factor injections. J Ophthalmic Vis Res. 2022;17(2):196-210. doi:10.18502/jovr.v17i2.10790