For neovascular age-related macular degeneration (AMD) patients, an intravitreal injection may cause short-term reductions in ocular perfusion independent from intraocular pressure (IOP), according to a study in Acta Opthalmologica.

Injecting an anti-vascular endothelial growth factor (anti-VEGF) agent is a common go-to treatment for AMD. However, as VEGF is a key regulator for retinal vascular tone, researchers have wondered if the application of anti-VEGF could induce alterations in ocular perfusion.

To test this theory, researchers studied 20 eyes from 20 Caucasian patients with unilateral neovascular AMD, and 20 fellow eyes. Investigators treated all eyes with standard intravitreal injection of aflibercept and then measured blood flow at the optic nerve head and the choroid. They also analyzed IOP, systolic and diastolic blood pressure, heart rate, mean arterial pressure and ocular perfusion pressure. The investigators performed measurements at baseline, immediately after the injection and then 30 and 45 minutes later. Mean time between the injection of aflibercept and the first follow-up was approximately nine minutes.

The investigators reported the injection led to a significant short-term rise in IOP. In the injected eyes, mean blur rate within the major vessels and the entire optic nerve head region decreased significantly. No change in mean blur rate was observed in the fellow eye. Researchers noted choroidal blood flow remained stable in both eyes, and no changes in choroidal perfusion were observed during the first 45 minutes after the injection.

The data shows intravitreal injection of aflibercept rapidly reduces perfusion in the optic nerve head and the central retinal vessels with no significant correlation to the short‐term rise in IOP, investigators said. Additionally, IOP increased significantly in the treated eye after the injection but declined to baseline values after 30 minutes, whereas optic nerve head and central retinal vessels were significantly reduced up to 60 minutes after the injection.

Researchers said this is the first study to evaluate the immediate influence of aflibercept on ocular perfusion in AMD.  Other anti-VEGF agents were not included in this study but the findings of this work do not suggest the phenomenon is exclusive to aflibercept.

Mursch-Edlmayr AS, Luft N, Podkowinski D, et al. Short-term effect on the ocular circulation induced by unilateral intravitreal injection of aflibercept in age-related maculopathy. Acta Opthalmol. March 27, 2019. [Epub ahead of print].