Reduced macular vessel density in COVID-19 patients with and without associated thrombotic events using optical coherence tomography angiography

Abstract

Purpose Thrombotic events (TE) represent one of the major complications of SARS-CoV-2 infection. The objective is to evaluate vessel density (VD) and perfusion density (PD) by optical coherence tomography angiography (OCTA) in COVID-19 patients, and compare the findings with healthy controls. The secondary objective is to evaluate if there are differences in OCTA parameters between COVID-19 patients with and without associated TE. Methods Cross-sectional case-control study that included patients with laboratory-confirmed diagnosis of COVID-19 with and without TE related to the infection and age-matched healthy controls. Ophthalmological examination and OCTA were performed 12 weeks after diagnosis. Demographic data and medical history were collected. Macular OCTA parameters in the superficial retinal plexus were analyzed according to ETDRS sectors. Results Ninety patients were included, 19 (20%) COVID-19 patients with associated TE, 47 (49.5%) COVID-19 patients without TE, and 29 (30.5%) healthy controls. Fifty-three (55.7%) were male, mean age 54.4 (SD 10.2) years. COVID-19 patients presented significantly lower VD than healthy controls: central (p = 0.003), inner ring (p = 0.026), outer ring (p = 0.001). PD was also significantly decreased: outer ring (p = 0.003), full area (p = 0.001). No differences in OCTA parameters were found between COVID-19 patients with and without TE. Conclusions OCTA represents a promising tool for the in vivo assessment of microvascular changes in COVID-19. Patients with SARS-CoV-2 infection show lower VD and PD compared to healthy controls. However, no differences were found between COVID-19 when considering TE. Prospective studies are required to further evaluate the retinal microvascular involvement of SARS-CoV-2 and its impact on the vasculature of other organs.

Use of Imaging Technology to Assess the Effect of COVID-19 on Retinal Tissues: A Systematic Review

“…Recovered COVID-19 eyes showed a significant increase in peripapillary retinal nerve fibre (RNFL) thickness and superficial and deep macular VDs in parafoveal and perifoveal regions compared with healthy controls. This study contradicts the studies reporting a reduction in VD in COVID-19 eyes [ 37 , 40 , 42 ].…”

“…Guemes Villahoz et al [ 40 ] performed OCTA in patients 12 weeks after COVID-19 diagnosis. Ninety patients were included, 19 (20%) COVID-19 patients with associated thrombotic events, 47 (49.5%) COVID-19 patients without thrombotic events, and 29 (30.5%) healthy controls.…”

Retinal vessels modifications in acute and post-COVID-19

“…The eyes can be affected at many levels by SARS-CoV-2 as the virus has been isolated in the tears 3 , the conjunctiva 4 and even the retina 5 . Although no disease-specific lesions have been described neither in the anterior nor in the posterior segment of the eye many authors have reported the occurrence of direct or indirect signs of retinal circulation alterations in patients with COVID-19 ranging from retinal haemorrhages and cotton wool spots 6 , retinal vein occlusions 7 , 8 to a significant reduction in vascular density measured by optical coherence tomography angiography 9 – 12 .…”

Ocular and Systemic Manifestations in Paediatric Multisystem Inflammatory Syndrome Associated with COVID-19

“…The ocular manifestation (conjunctivitis) is common in MIS-C associated with COVID-19 [7,8]. Retinal manifestations and SARS-Cov-2 detection in retina have also been reported [13][14][15]. Whether conjunctivitis is due to virus attack or related to an inflammatory response remains unknown.…”