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Retinal vascular occlusions in COVID-19 infection and vaccination: a literature review
Insights
Retinal vascular occlusions, including artery and vein occlusions, can be a rare manifestation of COVID-19, particularly in hypercoagulable patients. The link between COVID-19 vaccination and these occlusive events remains controversial due to limited evidence.
Area of Science:
- Ophthalmology
- Infectious Diseases
- Cardiology
Background:
- COVID-19 (coronavirus disease) is associated with hypercoagulability and increased thromboembolic risk.
- Retinal vascular damage has been suggested in COVID-19 patients, with reported cases of retinal vascular occlusions.
- This review investigates retinal vascular occlusions in individuals diagnosed with COVID-19 and those vaccinated against it.
Purpose of the Study:
- To review and investigate studies on retinal vascular occlusions in patients diagnosed with COVID-19.
- To examine the occurrence of retinal vascular occlusions in individuals vaccinated for COVID-19.
Main Methods:
- Systematic searches of PubMed and Google Scholar databases were conducted.
- Studies were identified using keywords such as "retinal occlusion," "SARS-CoV-2," "COVID-19," "coronavirus," and "vaccine."
- Searches covered literature up to January 7, 2022.
Main Results:
- Thirteen retinal artery occlusions (RAO) and 14 retinal vein occlusions (RVO) were identified in COVID-19 patients; ocular symptoms were the initial presentation in five cases.
- Among COVID-19 patients, 11 cases of acute macular neuroretinopathy (AMN) and/or paracentral acute middle maculopathy (PAMM) were reported, with spontaneous resolution in most.
- Twenty-six vaccinated individuals presented with retinal vascular occlusions (more RVO than RAO), with symptoms typically occurring within 3 weeks post-vaccination.
Conclusions:
- Retinal vascular occlusions may be a rare manifestation of COVID-19, especially in patients with hypercoagulability.
- The causal relationship between COVID-19 vaccines and retinal vascular occlusions is controversial due to a limited number of case reports.
Purpose:
Abnormal hypercoagulability and increased thromboembolic risk are common in patients with coronavirus disease (COVID-19). COVID-19 has been suggested to cause retinal vascular damage, with several studies on COVID-19 patients with retinal vascular occlusions. We reviewed and investigated studies on retinal vascular occlusions in patients diagnosed with COVID-19 and in those vaccinated for COVID-19.
Methods:
Studies that reported retinal vascular occlusion in COVID-19 patients or in vaccinated people were identified using the terms "retinal occlusion," together with "severe acute respiratory syndrome coronavirus 2", "SARS-CoV-2," "COVID-19," "coronavirus," and "vaccine," through systematic searches of PubMed and Google Scholar databases until January 7, 2022.
Results:
Thirteen cases of retinal artery occlusion (RAO) and 14 cases of retinal vein occlusion (RVO) were identified among patients diagnosed with COVID-19. Half of the patients with RAO or RVO revealed no systemic disorders except current or past COVID-19, and ocular symptoms were the initial presentation in five cases. Among patients with RAO, most presented with central RAO at 1-14 days of COVID-19 diagnosis, with abnormal coagulation and inflammatory markers. Among those with RVO, two-thirds presented with central RVO and one-third with RVO. Eleven cases with acute macular neuroretinopathy (AMN) and/or paracentral acute middle maculopathy (PAMM) were reported among patients with COVID-19, presenting scotoma resolved spontaneously in most cases. Among the 26 cases vaccinated with either mRNA or adenoviral vector vaccines for COVID-19 and presenting retinal vascular occlusions, there were more RVO cases than RAO cases, and ocular symptoms mostly occurred within 3 weeks after vaccination. One case presented bilateral AMN and PAMM after COVID-19 vaccination.
Conclusion:
Retinal vascular occlusions might be a manifestation of COVID-19, although rare, especially in patients at risk of systemic hypercoagulability and thromboembolism. For COVID-19 vaccines, the causal relationship is controversial because there are few case reports of retinal vascular occlusions after COVID-19 vaccination.
