Pediatric patients may experience retinal vascular and morphological changes after recovering from COVID-19, according to research published in Photodiagnosis and Photodynamic Therapy. These changes can be detected upon optical coherence tomography (OCT) or OCT-angiography (OCT-A) analysis and may exist despite normal fundus examination results.
Researchers included 64 eyes of 32 children in a prospective, cross-sectional, observational study. Retinal vascular and structural parameters were compared between children who had recovered from COVID-19 (n=16; mean age, 13.1 years, 12 girls; mean time following symptom onset, 34.8 days) and age- and sex-matched control individuals (n=16; mean age, 13.2 years, 12 girls). All participants underwent comprehensive eye examinations which included measurements of peripapillary retinal nerve fiber layer (pRNFL), ganglion cell complex (GCC), and choroidal thicknesses. Superficial and deep capillary plexus vessel densities and choriocapillaris layer flow area were also obtained.
Children who recovered from COVID-19 had thicker pRNFL, GCC, and choroidal thicknesses compared with participants in the control group (P <.005 for all). Patients who recovered from a COVID-19 infection had a mean pRNFL thickness of 117.8±12.3 µm while those who did not have COVID-19 had a mean thickness of 109.4±7.6 µm. GCC was 106.7±7.1 µm in the COVID-19 group, compared with 103.2±4.3 µm in the patients in the control group. Finally, patients in the COVID-19 group also had a mean choroidal thickness of 317.8±51.7 µm, vs 281.5±51.4 in the control group
However, superficial and deep capillary plexus vessel densities and choriocapillaris flow area values were significantly lower among those who recovered from COVID-19, according to the report.
“It has been reported that COVID-19 can cause microvascular damage due to hypercoagulability or diffuse endothelial inflammation,” according to the study authors. “Choriocapillaris flow area, [superficial capillary plexuses vessel density, deep capillary plexuses vessel density] (i.e., blood supply to the macular region) were significantly decreased in pediatric patients with COVID-19, relative to values observed in controls. Such findings may be explained by hyper-coagulation and enhanced thrombosis due to COVID-19. However, surprisingly, [radial peripapillary capillary vessel density] values (i.e., blood supply to the optic disc region) were significantly higher in the COVID-19 group than in the control group. Photoreceptors and ganglion cells located in the macular region require high levels of oxygen. An increase in [radial peripapillary capillary vessel density] may represent an attempt to compensate for COVID-19-induced ischemia in the macular region.”
Study limitations include a small sample size, short study duration, failure to correlate COVID-19 severity with observed changes, and a lack of fluorescein angiography assessments.
Demir ST, Dalgic N, Yesiltas SK, et al. OCT and OCTA evaluation of vascular and morphological structures in the retina in recovered pediatric patients with COVID-19. Photodiagnosis Photodyn Ther. Published online October 13, 2022. doi:10.1016/j.pdpdt.2022.103157