Possible association between vaccination against SARS-CoV-2 and recurrence of macular edema due to branch retinal vein occlusion: a case report.

We herein describe a patient who developed recurrence of macular edema (ME) due to branch retinal vein occlusion (BRVO) 3 days after administration of the BNT162b2 vaccine against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). A man in his early 50s visited our hospital because of vision loss in his right eye. His logarithmic best-corrected visual acuity (BCVA) was -0.79 in both eyes. ME due to superior temporal BRVO was observed in his right eye, and the central foveal thickness (CFT) was 486 µm. The patient was treated with an intravitreal aflibercept injection with logarithmic BCVA of -0.79, leading to resolution of the ME with a CFT of 299 µm. Three months after the initial visit, he received a fourth dose of an mRNA vaccine. Three days later, he developed vision loss in his right eye. Although the logarithmic BCVA was maintained at -0.79, ME recurred with a CFT of 507 µm. The patient was treated with an additional dose of intravitreal aflibercept injection. The ME resolved and the logarithmic BCVA in the right eye was maintained at -0.79. This case indicates a possible association between vaccination against SARS-CoV-2 and recurrence of ME due to BRVO.