Macular vessel density reduction in patients recovered from COVID-19: a longitudinal optical coherence tomography angiography study.

BACKGROUND/AIMS: To quantify the longitudinal changes of the macular microvasculature and the foveal avascular zone (FAZ) parameters in patients recovered from coronavirus disease-2019 (COVID-19) using optical coherence tomography angiography (OCTA) analysis. METHODS: This observational, longitudinal study was performed on patients recovered from COVID-19. The OCTA images were recorded at baseline and after 1 and 3 months at the follow-up examination. Vessel density (VD) of the retinal superficial (SCP) and deep capillary plexus (DCP), as well as the area of the FAZ of patients who had recovered from COVID-19, were measured. RESULTS: In total, 36 eyes of 18 patients (62.2% female) with a mean age of 34.5 ± 7.5 years old were included. Regarding SCP, while the VDs of the whole image, fovea, and parafovea were comparable at different time points, the mean VDs in inferior hemifield, as well as superior and inferior regions of perifovea, underwent significant reductions at month 3, compared to the baseline. In DCP, the mean of VD in the whole image was 54.3 ± 2.7 at the first visit which significantly decreased to 52.1 ± 3.8(P = 0.003) and 51.4 ± 2.7(P = 0.001) after 1 and 3 months, respectively. The VDs in all regions of parafovea and perifovea revealed a significant reduction after 1 and 3 months, compared to the first visit. The mean FAZ area was 0.27 ± 0.08 mm2, 0.26 ± 0.08 mm2, and 0.27 ± 0.08 mm2 at the baseline, month 1, and month 3, respectively (P > 0.05). CONCLUSION: Based on the results, the patients who had recovered from COVID-19 had a progressive decrease of VD at the follow-up visit 3 months after COVID-19 infection.