Optic Nerve Head Structural Changes After Intravitreal Injection

To evaluate the acute anatomical changes of Bruch's membrane opening (BMO) and optic nerve head (ONH) pit depth in patients receiving 0.05cc of anti-VEGF intravitreal injections (IVIs).

We prospectively enrolled patients receiving IVIs and collected data including age, sex, race, phakic status, presence or absence of glaucoma, injection agent utilized, axial length, and cup-to-disc ratio (C/D). High-resolution spectral domain OCT imaging and measurements were made pre- and within five minutes post-IVI.

Fifty-one eyes of 51 patients were included in the study. 35.29% of patients were male. The mean age at the time of IVI was 78.27 ± 11.17 years. The average change in the pit depth after IVI was 31.57 ± 24.36 μm (p < 0.001). The number of IVIs previously received significantly correlated with a decreased change in pit depth post-injection (r = -0.369, p = 0.004). No significant relationship was identified between categorical or continuous variables and the change in pit depth or BMO after IVI. No significant associations were identified between the magnitude of IOP elevation and the change in pit depth post-IVI (r = 0.03, p = 0.834) or the number of previous IVIs (r = 0.005, p = 0.973).

IVI was associated with a modest increase in ONH pit depth. The number of prior injections inversely correlated with this change, suggesting a potential cumulative effect on structural response. Given the link between ONH biomechanics and retinal nerve fiber layer (RNFL) thinning, our findings raise the possibility that repeated IVIs may contribute to structural changes relevant to glaucomatous progression.