Retinal Vascular Density and Thickness Changes May Follow COVID-19 Vaccination

COVID-19 vaccination may be responsible for short-term retinal vascular density and thickness changes.

Individuals undergoing COVID-19 vaccination with the Pfizer-BioNTech vaccine may experience retinal vascular density and thickness changes within a 3-day period, according to a study published in Microvascular Research. These changes may be attributed to vascular endothelial damage and inflammation, the report suggests.

Researchers included 40 health care professionals (60% women; mean age, 37.65 years) in the investigation and performed optical coherence tomography-angiography (OCT-A) assessment prior to COVID-19 vaccination and within 3 days following vaccination. The team compared retinal vascular density and thickness measurements obtained before and after COVID-19 vaccination.

The etiology of the ocular side effects of the Pfizer-BioNTech vaccine has not yet been clarified.

Compared with baseline values, participants undergoing vaccination experienced a significant reduction in total vascular (52% vs 50%; P <.0001), foveal vascular (21% vs 19.8%; P =.009), parafoveal vascular (54.4% vs 5.7%; P <.0001) and perifoveal vascular density of the superficial (51.4% vs 50.5%; P =.001) and deep capillary plexus (55.5% vs 52.1%; P =.04). Retinal foveal thickness and total retinal parafoveal thickness values increased significantly compared with pre-vaccination values (254 vs 258 µm; P =.03 and 319 vs 321 µm; P =.05, respectively).

“The etiology of the ocular side effects of the Pfizer-BioNTech vaccine has not yet been clarified,” according to the researchers. “These side effects are considered to be caused by a component of the vaccine, a hypersensitivity reaction, or autoimmunity. It has also been suggested that spike protein, human adenovirus, or other viral antigens may be responsible for such side effects.”

Study limitations include a small convenience sample, short study duration, and the inclusion of only 1 vaccine type.

This article originally appeared on Optometry Advisor


Gedik B, Erol MK, Suren E, et al. Evaluation of retinal and optic disc vascular structures in individuals before and after Pfizer-BioNTech vaccination. Microvasc Res. Published online February 4, 2023. doi:10.1016/j.mvr.2023.104500