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The Effect of Post-Coronavirus Disease 2019 Infection on the Retinal Microvasculature
Nermien Salah El-Dien Mohammed El-Haddad1,2, Elham Abd El-Wahed1, Adel Abd El-Wahab1
1Department of Ophthalmology, Faculty of Medicine, Al-Azhar University, Cairo, Egypt.
Insights
COVID-19 recovery impacts retinal microvasculature, with significant decreases in deep macular vessel density (DVD) and optic disc vessel density observed within one month. Superficial vessel density and the foveal avascular zone remained largely unaffected.
Area of Science:
- Ophthalmology
- Vascular Biology
- Infectious Disease Research
Background:
- Coronavirus disease 2019 (COVID-19) is known to affect multiple organ systems.
- Emerging evidence suggests potential ocular manifestations following COVID-19 infection.
Purpose of the Study:
- To investigate short-term changes in the retinal microvasculature of the macula and optic disc in patients recovering from COVID-19.
- To compare microvascular changes between patients with varying COVID-19 severity and healthy controls.
Main Methods:
- Optical coherence tomography angiography (OCTA) was used to assess macular and optic disc vessel density (VD) in 100 post-COVID-19 patients and 50 controls.
- Measurements included deep and superficial macular VD, optic disc VD, and foveal avascular zone (FAZ) area.
- Patients were evaluated within one month of recovery, confirmed by negative PCR tests.
Main Results:
- A significant reduction in deep macular vessel density (DVD) was observed in post-COVID-19 patients, particularly those with severe disease (P=0.002).
- Optic disc vessel density, including peripapillary capillaries, also showed a significant decrease, especially in severe cases.
- Superficial macular vessel density (SVD) showed a minor reduction in one area (P=0.037), while foveal VD and FAZ remained unaffected.
Conclusions:
- Retinal microvasculature, particularly deep macular and optic disc vessels, is affected in the first month after COVID-19 recovery.
- Deep vessel density reduction was more pronounced than superficial vessel density changes.
- These findings highlight the persistent vascular impact of COVID-19 on the eye.
Purpose:
To evaluate the short-term microvasculature changes of the macula and optic disc following coronavirus disease 2019 (COVID-19).
Methods:
This study included 150 eyes (50 eyes of healthy controls and 100 eyes of patients) during the 1st month following COVID-19 recovery, as evidenced by two negative polymerase chain reactions. A complete ophthalmic examination and optical coherence tomography angiography were performed to detect the deep and superficial macular vessel density (VD). In addition, the VD of the optic disc was evaluated.
Results:
Deep VD (DVD) showed a statistically significant decrease in post-COVID-19 patients, particularly those with severe COVID-19. This reduction occurred in the whole image, parafoveal, and perifoveal VD (P = 0.002, P = 0.002, and P < 0.001, respectively). Concerning the superficial VD (SVD), only the superior hemisphere of the whole image density was statistically significantly reduced (P = 0.037). There was no statistically significant difference in foveal VD (both deep and superficial vessel) among the study groups (P = 0.148 and P = 0.322, respectively). Regarding the foveal avascular zone (FAZ), there was no statistically significant among groups (P = 0.548). Regarding the optic disc, the whole image VD and redial peripapillary capillary VD demonstrated a highly significant decrease, particularly in cases of severe COVID-19. Conversely, inside disc VD showed a nonsignificant change among the study groups.
Conclusions:
According to the findings of the current study, retinal microvasculature was affected in the 1st month following recovery from COVID-19. DVD was significantly reduced more than SVD. In addition, peripapillary VD decreased, whereas the FAZ was unaffected.
