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Relationship Between COVID-19 and Retinal Artery Occlusions
Tetsuya Muto1,2,3, Shigeki Machida1, Shinichiro Imaizumi2
1Department of Ophthalmology, Dokkyo Medical University Saitama Medical Center, Koshigaya, Japan, saitama-med.ac.jp.
Insights
The link between COVID-19 infection or vaccination and retinal artery occlusions (RAOs) is unclear. While some reports suggest an increase in RAOs post-COVID-19, further research is needed to confirm this association.
Area of Science:
- Ophthalmology
- Infectious Diseases
- Cardiovascular Medicine
Background:
- The association between coronavirus disease 2019 (COVID-19) infection or vaccination and retinal artery occlusions (RAOs) is debated.
- Both COVID-19 and its vaccination have been implicated in thrombin formation, a known cause of RAOs.
Purpose of the Study:
- To investigate the relationship between COVID-19 infection/vaccination and the occurrence of RAOs.
- To analyze patient demographics, timing of events, and visual acuity outcomes in RAO cases potentially linked to COVID-19.
Main Methods:
- Review of existing case reports investigating RAO incidence following COVID-19 infection or vaccination.
- Analysis of reported average ages, time from diagnosis/vaccination to symptom onset, and visual acuity outcomes.
Main Results:
- RAOs occurred in patients with a mean age of 48.7 years (central RAO) and 41.3 years (branch RAO) post-infection, and 54.7 years (CRAO) and 62.3 years (BRAO) post-vaccination.
- Mean time to symptom onset varied from 7.3 days (post-vaccination CRAO) to 48.3 days (post-infection BRAO).
- Initial and final visual acuities varied, with some data unavailable for branch RAOs.
Conclusions:
- Current evidence is insufficient to definitively establish a causal link between COVID-19 or its vaccine and RAOs.
- The possibility of such a relationship cannot be excluded, necessitating further investigation.
- Understanding this association is crucial given the potential for future pandemics.
Abstract:
The relationship between coronavirus disease 2019 (COVID-19) infection or vaccination and retinal artery occlusions (RAOs) remains controversial. COVID-19 infection or vaccination can sometimes cause thrombin formation. RAOs occur due to thrombin in the retinal artery. The average age of occurrence after COVID-19 infection was 48.7 ± 17.2 years in central RAO (CRAO) and 41.3 ± 17.8 years in branch RAO (BRAO). After COVID-19 vaccination, the average age was 54.7 ± 17.1 years in CRAO and 62.3 ± 21.2 years in BRAO. The mean time from COVID-19 diagnosis to symptom onset was 10.5 ± 9.3 days in CRAO and 48.3 ± 39.6 days in BRAO. After vaccination, the mean time was 7.3 ± 6.8 days in CRAO and 21.0 ± 24.9 days in BRAO. Initial visual acuity (VA) after COVID-19 infection was 2.53 ± 0.65 in CRAO and 0.09 ± 0.07 in BRAO. Final VA was 2.73 ± 0.12 in CRAO, but data for BRAO were unavailable. After vaccination, initial VA was 2.28 ± 0.97 in CRAO and -0.02 ± 0.16 in BRAO. Final VA was 2.12 ± 1.24 in CRAO and could not be calculated in BRAO. The relationship between COVID-19 or its vaccination and RAOs was investigated through past case reports. Two types of reports existed regarding RAO incidence after the COVID-19 pandemic-some indicated an increase, while others found no change. No reports suggested a decrease in RAO occurrence. The current evidence does not clarify the relationship between COVID-19 or its vaccine and RAOs. However, this relationship cannot be ruled out. Further investigations are necessary, as future infectious disease pandemics may occur.
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