Children who have recovered from a COVID-19 infection present increased retinal vessel density (VD), macular perfusion density (mPD), and peripapillary flux index (FI), representing possible in vivo biomarkers of vascular abnormalities in other organs, according to findings published in the Journal of AAPOS.
Researchers conducted a cross-sectional case-control study to evaluate retinal vascular changes in pediatric patients who have recovered from COVID-19 using optical coherence tomography angiography (OCT-A), and to compare the results with age-matched healthy children. The study compared children (age range 6-18 years) with laboratory-confirmed SARS-CoV-2 infection (n=27) with historic healthy controls (n=45).
An ophthalmological examination, which included fundus photography and OCT-A of the macular region and optic disc, was performed on all participants. Children with COVID-19 were examined 4 to 8 weeks after diagnosis, and symptoms, demographic data, and medical history were noted. According to Early Treatment of Diabetic Retinopathy (ETDRS) sectors and peripapillary quadrants, OCT-A parameters in the superficial capillary plexus (SCP) were analyzed.
OCT-A images of the SCP showed that VD was significantly increased in the inner ring following COVID-19 infection, compared with patients who were not infected (P =.001). Also, patients who had COVID-19 demonstrated increased mPD in the inner ring (P =.001), and a significantly higher FI in all 4 quadrants, as shown by peripapillary OCT-A (P <.001).
The researchers explain that, while the present study found increases in retinal VD and other vascular OCT-A parameters, previous studies have found a reduction in these factors in adults.
They indicate that the exact reason for these conflicting results “is not precisely understood, although the apparent differences in immune response to SARS-CoV-2 infection and the anatomical and structural differences between the adult and pediatric retina might partially account for these findings.”
Study limitations include a relatively small sample size and the fact that it was not possible to perform the ophthalmological examination in the acute stage of COVID-19, due to strict safety and control protocols. Additionally, some participants were asymptomatic or presented with mild COVID-19, and differences according to severity could not be analyzed.
Güemes-Villahoz N, Burgos-Blasco B, Perez-Garcia P, et al. Retinal and peripapillary vessel density increase in recovered COVID-19 children by optical coherence tomography angiography. Journal of AAPOS. Published online October 20, 2021. doi:10.1016/j.jaapos.2021.06.004