Macular vessel density in patients recovered from COVID 19

The purpose is to evaluate macular vascular densities (VDs) using optical coherence tomography angiography (OCTA) in patients effected by coronavirus disease-2019 (COVID-19).

The superficial (SF) and deep macular VD of 50 patients with SARS CoV2 pneumonia who had positive polymerase chain reaction (PCR) tests and who recovered after receiving treatment and 55 healthy age- and gender-matched controls were compared using OCTA. Blood inflammation parameters were also recorded.

There was no statistically significant difference between the two groups in terms of age and gender (p = 0.147 and p = 0.504, respectively). Nor was there a difference with respect to smokers between the two groups (p = 0.231). In COVID-19 patients, the VDs in superior hemi quadrant, superior quadrant and inferior quadrant, were significantly lower (p = 0.033, p = 0.029 and p = 0.042, respectively) in superficial plexus. It was also significantly lower in parafovea, superior hemi and superior quadrants (p = 0.026, p < 0.001 and p = 0.004, respectively) in deep plexus. In addition, white blood cell and neutrophil counts were significantly negatively correlated with the VD of the deep parafovea, deep superior quadrant and deep superior hemi quadrant (p < 0.05). There was no difference between the patient and control groups in both superficial and deep foveal avascular zone (FAZ) (p = 0.101 and p = 0.691 respectively).

In COVID-19 disease, VD is low in some sectors in both SF and deep layers, but no change in FAZ. The effect of COVID 19 disease on the retina and whether it makes the retina sensitive to damage can only be understood with long-term follow-up.