Quantitative assessment of retinal changes in COVID-19 patients

Changes in retinal nerve fiber layer thickness may be the cause of post-COVID-19 headaches

OBJECTIVE

The prevalence of post-COVID headaches is not low. The eye can be affected by this infection, but it is not clear yet what the relationship is between persistent headaches and the thickness of the retinal nerve fiber layer (RNFL) after COVID-19 infection this study aims to investigate the relationship between these subjects.

METHODS

In this retrospective study, in patients who have had a persistent headache, SD-OCT analysis of RNFL was obtained, and RNLF thickness values before and after COVID-19 infection were analyzed.

RESULTS

A total of 26 eyes from 13 patients (nine (69.2%) females, four (30.8%) males) with persistent headaches after COVID-19 infection were studied. The average age was 47,35 years for females and 63 years for males. The mean RNFL thickness of both eyes between before and after COVID-19 infection decreased, which was statistically significant.

CONCLUSION

In this study, a correlation between headache and changes in RNLF after COVID-19 infection was found. It may have wider ramifications to look into the COVID-19-associated headache phenotype of people with a history of migraines, contributing to a more comprehensive understanding of migraine pathogenesis. This relationship can provide further insight into this infection.

New findings on retinal microvascular changes in patients with primary COVID-19 infection: a longitudinal study

Purpose

To investigate the longitudinal alterations of retinal microvasculature in patients with primary coronavirus disease 2019 (COVID-19) infection.

Methods

A cohort of participants, who had never been infected with COVID-19, was recruited between December 2022 and May 2023 at Peking Union Medical College Hospital in Beijing, China. Participants underwent comprehensive ophthalmologic examinations and fundus imaging, which included color fundus photography, autofluorescence photography, swept-source optical coherence tomography (SS-OCT) and SS-OCT angiography (SS-OCTA). If participants were infected with COVID-19 during the study, follow-ups with consistent imaging modality were conducted within one week and two months after recovery from the infection.

Results

31 patients (61 eyes), with a mean age of 31.0 ± 7.2 years old, were eligible for this study. All participants contracted mild COVID-19 infection within one month of baseline data collection. The average period was 10.9 ± 2.0 days post-infection for the first follow-up and 61.0 ± 3.5 days for the second follow-up. No clinical retinal microvasculopathy features were observed during the follow-ups. However, SS-OCTA analysis showed a significant increase in macular vessel density (MVD) from 60.76 ± 2.88% at baseline to 61.59 ± 3.72%(p=0.015) at the first follow-up, which subsequently returned to the baseline level of 60.23 ± 3.33% (p=0.162) at the two-month follow-up. The foveal avascular zone (FAZ) remained stable during the follow-ups with areas of 0.339 ± 0.097mm2, 0.342 ± 0.093mm2, and 0.344 ± 0.098mm2 at the baseline, first follow-up (p=0.09) and second follow-up (p=0.052), respectively. Central macular thickness, cube volume and ganglion cell-inner plexiform layer showed a transient decrease at the first follow-up(p<0.001, p=0.039, p=0.002, respectively), and increased to baseline level at the two-month follow-up(p=0.401, p=0.368, p=0.438, respectively).

Conclusion

Mild COVID-19 infection may temporarily and reversibly impact retinal microvasculature, characterized by a transient increase in retinal blood flow during the early recovery phase, which returns to the pre-infection level two months post-infection.

Ocular manifestations of COVID-19: A systematic review of current evidence

Introduction

COVID-19 caused by SARS-CoV-2, commonly presents with symptoms such as fever and shortness of breath but can also affect other organs. There is growing evidence pointing to potential eye complications. In this article, we aim to systematically review the ocular manifestations of COVID-19.

Methods

We conducted a systematic review to explore the ocular manifestations of COVID-19. We searched online databases including PubMed, Embase, Scopus, and Web of Science up to September 4, 2023. After a two-stage screening process and applying inclusion/exclusion criteria, eligible articles were advanced to the data extraction phase. The PRISMA checklist and Newcastle-Ottawa Scale (NOS) were used for quality and bias risk assessments.

Results

We selected and extracted data from 42 articles. Most of the studies were cross-sectional (n = 33), with the highest number conducted in Turkey (n = 10). The most frequent ocular manifestation was conjunctivitis, reported in 24 articles, followed by photophobia, burning, chemosis, itching, and ocular pain. Most studies reported complete recovery from these manifestations; however, one study mentioned visual loss in two patients.

Conclusion

In general, ocular manifestations of COVID-19 appear to resolve either spontaneously or with supportive treatments. For more severe cases, both medical treatment and surgery have been employed, with the outcomes suggesting that complete recoveries are attainable.

Retinal Microvasculature Image Analysis Using Optical Coherence Tomography Angiography in Patients with Post-COVID-19 Syndrome

Several optical coherence tomography angiography (OCT-A) studies have demonstrated retinal microvascular changes in patients post-SARS-CoV-2 infection, reflecting retinal-systemic microvasculature homology. Post-COVID-19 syndrome (PCS) entails persistent symptoms following SARS-CoV-2 infection. In this study, we investigated the retinal microvasculature in PCS patients using OCT-angiography and analysed the macular retinal nerve fibre layer (RNFL) and ganglion cell layer (GCL) thickness via spectral domain-OCT (SD-OCT). Conducted at the Manchester Royal Eye Hospital, UK, this cross-sectional study compared 40 PCS participants with 40 healthy controls, who underwent ophthalmic assessments, SD-OCT, and OCT-A imaging. OCT-A images from the superficial capillary plexus (SCP) were analysed using an in-house specialised software, OCT-A vascular image analysis (OCTAVIA), measuring the mean large vessel and capillary intensity, vessel density, ischaemia areas, and foveal avascular zone (FAZ) area and circularity. RNFL and GCL thickness was measured using the OCT machine's software. Retinal evaluations occurred at an average of 15.2 ± 6.9 months post SARS-CoV-2 infection in PCS participants. Our findings revealed no significant differences between the PCS and control groups in the OCT-A parameters or RNFL and GCL thicknesses, indicating that no long-term damage ensued in the vascular bed or retinal layers within our cohort, providing a degree of reassurance for PCS patients.

Alterations in the optic nerve and retina in patients with COVID-19. A theoretical review

The objective of this research is to identify and systematize the medical conditions generated by SARS-CoV-2 on the optic nerve and retina of young, adult, and elderly adults who suffered from COVID-19 in the period 2019-2022. A theoretical documentary review (TDR) was conducted within the framework of an investigation to determine the current state of knowledge of the subject under study. The TDR includes the analysis of publications in the scientific databases PubMed/Medline, Ebsco, Scielo and Google. A total of 167 articles were found, of which 56 were studied in depth, and these evidence the impact of COVID-19 infection on the retina and optic nerve of infected patients, both during the acute phase and in subsequent recovery. Among the reported findings, the following stand out: anterior and posterior non-arteritic ischemic optic neuropathy, optic neuritis, central or branch vascular occlusion, paracentral acute medial maculopathy, neuroretinitis, as well as concomitant diagnoses such as possible Vogt-Koyanagi-Harada disease, multiple evanescent white dot syndrome (MEWDS), Purtscher-like retinopathy, among others.

Tomographic Findings in the Retina of Unvaccinated Patients with COVID Pneumonia: Prospective Longitudinal Study

There is no definitive evidence on the extent of SARS-CoV-2's effect on the retina. This study aims to determine if the natural history of SARS-CoV-2 infection affects tomographic findings in the retina of patients with COVID-19 pneumonia. This is a prospective cohort study of patients hospitalized with COVID-19 pneumonia. The patients underwent ophthalmological explorations and optical coherence tomography during the acute phase of the infection and at a follow-up 12 weeks later. The primary outcomes were the central retinal thickness and central choroidal thickness, which were compared longitudinally and with non-COVID-19 historical controls. No statistically relevant differences were observed in the longitudinal analysis of the thickness of the central retina (p = 0.056), central choroid (p = 0.99), retinal nerve fiber layer (p = 0.21), or ganglion cell layer (p = 0.32). Patients with acute COVID-19 pneumonia showed significantly greater central retinal thickness than non-COVID controls (p = 0.006). In conclusion, tomographic measures of the retina and choroid are not influenced by the phase of COVID-19 infection and remain stable during 12 weeks. The central retinal thickness may increase in the acute phase of COVID-19 pneumonia, but more epidemiological studies using optical coherence tomography in the early stages of the disease are needed.

Retinal tissue and microvasculature loss in COVID-19 infection

This cross-sectional study aimed to investigate the hypothesis that permanent capillary damage may underlie the long-term COVID-19 sequela by quantifying the retinal vessel integrity. Participants were divided into three subgroups; Normal controls who had not been affected by COVID-19, mild COVID-19 cases who received out-patient care, and severe COVID-19 cases requiring intensive care unit (ICU) admission and respiratory support. Patients with systemic conditions that may affect the retinal vasculature before the diagnosis of COVID-19 infection were excluded. Participants underwent comprehensive ophthalmologic examination and retinal imaging obtained from Spectral-Domain Optical Coherence Tomography (SD-OCT), and vessel density using OCT Angiography. Sixty-one eyes from 31 individuals were studied. Retinal volume was significantly decreased in the outer 3 mm of the macula in the severe COVID-19 group (p = 0.02). Total retinal vessel density was significantly lower in the severe COVID-19 group compared to the normal and mild COVID-19 groups (p = 0.004 and 0.0057, respectively). The intermediate and deep capillary plexuses in the severe COVID-19 group were significantly lower compared to other groups (p < 0.05). Retinal tissue and microvascular loss may be a biomarker of COVID-19 severity. Further monitoring of the retina in COVID-19-recovered patients may help further understand the COVID-19 sequela.

The effect of various types of COVID-19 vaccines on the retinal microvasculature

PURPOSE

To detect the effect of various types of COVID-19 vaccine on macular and optic disc microvasculature.

METHOD

One hundred subjects receiving various types of COVID-19 vaccine (AstraZeneca, Sinopharm, Sinovac, Pfizer, and Moderna) were included in this study. A complete ophthalmic examination was done which included best-corrected visual acuity measurement, slit-lamp biomicroscopy, intraocular pressure measurement with Goldmann applanation tonometry, and fundus examination. Optical coherence tomography angiography (OCT-A) was done before and 1 week after receiving the vaccine. Superficial and deep macular capillary densities were measured in the form of the whole image, fovea, parafoveal, and perifoveal capillary density. Optic disc vessel density in the form of the whole disc, inside disc, and peripapillary were also measured.

RESULTS

The superficial macular vessel densities, (whole image, fovea, parafoveal, and perifoveal) showed statistically non-significant changes with P-values (0.269, 0.167, 0.346, and 0.476) respectively. Also, the deep macular vessel densities showed statistically non-significant changes with P-values (0.491, 0.096, 0.724, and 0.386) for the whole image, fovea, parafoveal, and perifoveal respectively. Moreover, RPC (radial peripapillary capillary) density showed no significant changes either (the whole disc, inside disc, or peripapillary) with P-values (0.807, 0.141, 0.883) respectively.

CONCLUSION

Various types of COVID-19 vaccines had no statistically significant effects on macular or optic disc microvasculature.

The Comparison of Retinal Microvascular Findings in Acute COVID-19 and 1-Year after Hospital Discharge Assessed with Multimodal Imaging-A Prospective Longitudinal Cohort Study

This study aimed to quantify possible long-term impairment of the retinal microcirculation and microvasculature by reassessing a cohort of patients with acute COVID-19 without other known comorbidities one year after their discharge from the hospital. Thirty patients in the acute phase of COVID-19 without known systemic comorbidities were enrolled in this prospective longitudinal cohort study. Fundus photography, SS-OCT, and SS-OCTA using swept-source OCT (SS-OCT, Topcon DRI OCT Triton; Topcon Corp., Tokyo, Japan) were performed in the COVID-19 unit and 1-year after hospital discharge. The cohort's median age was 60 years (range 28-65) and 18 (60%) were male. Mean vein diameter (MVD) significantly decreased over time, from 134.8 μm in the acute phase to 112.4 μm at a 1-year follow-up (p < 0.001). A significantly reduced retinal nerve fiber layer (RNFL) thickness was observed at follow-up in the inferior quadrant of the inner ring (mean diff. 0.80 95% CI 0.01-1.60, p = 0.047) and inferior (mean diff. 1.56 95% CI 0.50-2.61, p < 0.001), nasal (mean diff. 2.21 95% CI 1.16-3.27, p < 0.001), and superior (mean diff. 1.69 95% CI 0.63-2.74, p < 0.001) quadrants of the outer ring. There were no statistically significant differences between the groups regarding vessel density of the superior and deep capillary plexuses. The transient dilatation of the retinal vessels in the acute phase of COVID-19, as well as RNFL thickness changes, could become a biomarker of angiopathy in patients with severe COVID-19.

Relationship of the main indicators of systemic COVID-associated endotheliopathy with the morphofunctional state and hemodynamics of the retina and chorioid in the acute period of the disease

BACKGROUND: Nonspecific angio- and retinopathy is one of the clinical manifestations of a new coronavirus infection. The frequency of occurrence of these changes in people with severe COVID-19 does not exceed 55%. The causes, course and consequences of these microcirculatory disorders of the retina are currently not well understood. AIM: To study and compare of retinal morphometric parameters and systemic endothelial dysfunction markers, as well as the main clinical and laboratory parameters in patients with moderate and severe coronavirus infection during convalescence. MATERIALS AND METHODS: The study involved 44 patients (86 eyes) who had COVID-19 during the previous 3 months, who were divided into 2 groups: with moderate and severe disease. The control group consisted of 18 healthy volunteers (36 eyes). All patients underwent a standard ophthalmological examination and optical coherence tomography, which included an assessment of the choroidal thickness (CT) and measurement of the mean diameter of the peripapillary arteries (MAD) and veins (MVD). During hospitalization, all patients underwent a laboratory study of venous blood parameters, as well as an assessment of the microcirculation of the sublingual plexus by examining the density of the endothelial glycocalyx (PBR) using the GlycoCheck. RESULTS: In patients who underwent COVID-19, there was a significant increase in CT relative to the control group, amounting to 308, 344 and 392 m, respectively. The most pronounced difference was observed between MVD in patients with severe infection and the control group (119.1 m vs. 99.2 m). In patients with moderate and severe COVID-19, MAD and MVD were positively correlated with TC, with r = 0.389 and r = 0.584, respectively. MVD also correlated with the level of leukocytes (r = 0.504), the ESR value (r = 0.656). Correlations between MVD and data characterizing the state of the glycocalyx in the sublingual vascular plexus were revealed: the filling of small capillaries with erythrocytes (r = 0.587), as well as the marginal perfusion value in large capillaries 2025 m (r = 0.479) and PBR (r = 0.479). Only significant differences and correlations are shown (p 0.005). CONCLUSIONS: In patients who underwent moderate and severe COVID-19 during the convalescence period (up to 30 days), an increase in the diameter of peripapillary vessels and TC is observed, proportional to the severity of COVID-19, laboratory markers of systemic inflammation and hypercoagulation (the number of leukocytes, the ESR value, D-dimer and prothrombin), which indicates the inflammatory nature of the changes. The severity of postcovid retinal microangiopathy correlates with indicators detecting a decreasing of the endothelial glycocalyx thickness in the sublingual capillary plexus, which indirectly indicates a connection with systemic endotheliopathy.

Comparison of Endogenous Endophthalmitis in Patients with and Without COVID-19 Infection

INTRODUCTION

Endogenous endophthalmitis (EE) is an ophthalmic emergency that can have severe sight-threatening complications. Prompt diagnosis and aggressive treatment are central to the successful management of EE. In recent years, a significant increase has occurred in the number of cases of EE. Some of these individuals had a COVID-19 infection. The current study compared EE in patients with and without COVID-19 infection.

METHODS

All cases of EE admitted to Khalili Hospital between April 2020 and September 2021 were included in this prospective case-control study. Patients were divided into 2 groups: (i) the case group (EE patients with confirmed COVID-19 infection; n = 7) and (ii) the control group (EE patients without a history or evidence of COVID-19 infection; n = 7). Age, sex, presenting and final visual acuity, systemic diseases and risk factors for EE, anterior segment and fundus findings, hospitalization due to COVID-19, intensive care unit (ICU) admission, systemic steroid therapy, results of the sepsis workup, causative microorganism, types of treatment (pars plana vitrectomy vs. intravitreal or antifungal antibiotics), and follow-up period were recorded.

RESULTS

Twenty-four eyes of the 14 patients were included in this study, of which 9 were female. The mean age was 49.57 years. Follow-ups ranged from 1 month to 20 months (mean, 8 months). There were no statistically significant differences in age (P = 0.653), mean follow-up (P = 0.943), gender (P = 0.313), and clinical presentation (P = 0.409) between the case and control groups. Seven patients (50%) had positive intraocular culture results. Two out of 7 patients had a history of COVID-19 infection. The most common causative microorganism was Candida (4 patients [28.57%]; 6 eyes [25%]). No statistically significant differences were observed between the 2 groups in the need for vitrectomy (P = 1.000). The visual outcome between the 2 groups was similar (P = 0.179).

CONCLUSION

The COVID-19 infection does not seem to affect the severity, visual outcomes, improvement rate, or vitrectomy rate of EE. Early diagnosis and management, especially pars plana vitrectomy, can prevent serious complications and save many eyes.

Analysis of macular structure in age-related cataract patients with different antibody levels of severe acute respiratory syndrome coronavirus-2 vaccine

Objective

To analyze the macular structure of age-related cataract (ARC) patients with different antibody levels after COVID-19 vaccine injection, in order to obtain the effect of COVID-19 vaccine on the macular structure, and speculate whether the COVID-19 vaccine has adverse effects on the macular structure.

Methods

This retrospective study is conducted to analysis on the status of COVID-19 vaccine and the thickness of different layers at different positions in the macular area of ARC patients. In the age, sex and eye axial length matched population, in the un-injection, no-antibody, IgM and IgG positive groups after vaccination, the choroid, ganglion cell complex, nerve fiber layer and retinal thickness at different positions of ETDRS zoning in the macular area were discussed.

Results

A total of 164 patients (164 eyes) were included in the analysis. There were 63 males and 101 females. The average age was 65.99 ± 8.43 years. There was no significant difference in age and sex among the groups (p>0.05). The average axial length of 164 eyes was 23.56 ± 1.46mm, and no significant difference between the groups (p>0.05). Non parametric test and ANOVA test for the thickness of choroid, retina, ganglion cell complex and retinal nerve fiber layer in each division of ETDRS showed no significant difference in the four groups of un-injection, no-antibody, IgM and IgG (p>0.05). There was no correlation between the antibody concentration and the thickness of macular structure (p>0.05).

Conclusion

There was no significant difference in the thickness of choroid, retina, ganglion cell complex and retinal fiber layer in different macular areas after COVID-19 vaccine injection. There was no linear correlation between the thickness of choroid, retina, ganglion cell complex and retinal fiber layer and the antibody concentration produced after COVID-19 vaccine injection. It suggests that the injection of COVID-19 vaccine might have no significant effect on the macular structure of eye.

The impact of acute COVID-19 on the retinal microvasculature assessed with multimodal imaging

PURPOSE

To quantify retinal microvascular findings in the acute phase of COVID-19 using multimodal imaging and compare them with healthy, age-matched controls.

METHODS

Hospitalized patients in the acute phase of COVID-19 without known systemic comorbidities (n = 75) and healthy controls (n = 101) aged 18-65 were enrolled in this prospective cross-sectional study. The retinal microcirculation and microvasculature impairments were assessed using fundus photography, swept-source optical coherence tomography, and swept-source optical coherence tomography angiography in the COVID-19 unit and compared with healthy, age-matched controls.

RESULTS

Retinal findings were predominately observed in patients with severe disease (P = 0.006). Patients with severe disease were shown to have increased both mean vein diameter (Coef. = 19.28, 95% CI: 7.34-31.23, P = 0.002) and mean artery diameter (Coef. = 11.07, 95% CI: 0.84-21.67, P = 0.044). Neither blood vessel diameters were correlated with any confounding variables (age, sex, treatment with oxygen, LDH, or ferritin). Patients with severe COVID-19 were shown to have significantly increased retinal nerve fiber layer thickness in the superior and inferior quadrants both in the inner (S: P = 0.046; I: P = 0.016) and outer (S: P = 0.026; I: P = 0.014) ring and significantly increased GCL thickness in the outer temporal quadrant (P = 0.038). There were no statistically significant differences in vessel density or the foveal avascular zone area between the groups.

CONCLUSION

The severity of COVID-19 was significantly correlated with the presence of retinal microangiopathy, which could become a biomarker of angiopathy in patients with COVID-19.

Spectral-domain optical coherence tomography assessment of retinal and choroidal changes in patients with coronavirus disease 2019: a case-control study

Objectives

This study aimed to evaluate the retinal and choroidal changes in the macular region of patients with Coronavirus Disease 2019 (COVID-19) using structural spectral-domain optical coherence tomography (SD-OCT) analysis.

Methods

This cross-sectional observational case-control study included patients recovered from COVID-19. The COVID-19 in all participants was confirmed using the reverse transcription-polymerase chain reaction (RT-PCR) technique. The participants had mild to moderate degree of disease without a history of hospitalization, steroid usage, or blood saturation below 92%. Macular SD-OCT was performed at least two weeks and up to one month after recovery from systemic COVID-19. Quantitative and qualitative changes detected by macular SD-OCT imaging were evaluated in COVID-19 recovered patients and compared with the results of age-matched normal controls.

Results

Participants in this study included 30 cases (60 eyes) and 60 healthy controls (120 eyes). In total, 17 (28.3%) eyes in patient group showed at least one abnormal finding indicated by macular SD-OCT imaging included hyperreflective lesions in different retinal layers. In addition, dilated choroidal vessels and retinal pigment epitheliopathy were evident in 41 (68.3.6%) and 4 (6.6%) eyes in patient group, respectively, and their OCT findings resembled those with pachychoroid spectrum. No statistically significant differences were observed in retinal layers or retinal volume between the two groups. The mean ± SD subfoveal choroidal thickness (SFCT) was determined at 380.3 ± 12.40 μm, which was significantly thicker than that in control group (310.7 ± 57.5 μm) (P < 0.001).

Conclusion

Regarding retinal thickness, no significant change was observed in different retina layers of patients with COVID-19; however, there were striking qualitative changes, such as hyperreflective lesions in different retinal layers. The evaluation of choroidal structure and thickness demonstrated remarkable abnormal pachyvessels and significant thickening of the SFCT but the clinical significance of these findings is unknown.

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

PURPOSE

To evaluate the effect of COVID-19 on retinal tissues by conducting a systematic review and meta-analysis of the current literature.

BACKGROUND

The novel coronavirus disease is not yet well understood. The orbit provides a window into the body's microvasculature, and as such, it is a non-invasive opportunity to analyse the systemic circulation in vivo. By analysing the current literature, we test the hypothesis that non-invasive imaging of the retina could provide insight into the effect of COVID-19 on the retinal microvasculature.

METHODS

For this systematic review and meta-analysis, we screened PubMed databases and LitCOVID19 using the search criteria: (OCTA or Optical Coherence Tomography Angiography) AND (COVID-19 or corona or SARS-CoV-2) AND (retina or fundus). Databases were searched on 11 January 2022. The primary study outcomes were studies that utilised OCTA to analyse the retina; secondary outcomes involved studies that involved other imaging modalities such as OCT, fundus photography, and fundus autofluorescence.

FINDINGS

The total number of studies included in this review was 32. Optical coherence tomography angiography scans show reduced central retinal vascular density, a thinner ganglion cell layer, a thicker retinal nerve fibre layer, and an enlarged foveal avascular zone. Optical coherence tomography scans demonstrate a thicker central macular thickness and other changes to the macula, ganglion cell, and inner nuclear layers. Many fundus photographs depicted cotton wool spots, microhaemorrhages, and vascular occlusions. Non-invasive imaging technology has demonstrated that COVID-19 can profoundly affect the retina. Therefore, there is a requirement for long-term follow-up of COVID-19 patients to assess whether the retinal damage caused by COVID-19 is reversible.

COVID-19-Related Retinal Micro-vasculopathy - A Review of Current Evidence

PURPOSE

To evaluate the occurrence of retinal microvasculopathy in patients infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and who developed coronavirus disease (COVID-19).

DESIGN

Systematic review and meta-analysis.

METHODS

The Pubmed and Embase databases were comprehensively searched to identify studies that reported retina vascular changes in eyes with COVID-19. Two independent reviewers selected papers and extracted data for analysis. Data of interest were extracted and analyzed in RevMan Web versions 3.3. Quality of evidence was assessed using the National Institute of Health quality assessment tool for a case-control study.

RESULTS

Thirty-one studies reporting on 1373 subjects (972 COVID-19 and 401 controls) were included. Only case-control studies were included in the pooled analysis. There was a significantly higher likelihood of retinal microvasculopathy in subjects with COVID-19 compared to controls (odds ratio [95% confidence interval], 8.86 [2.54-27.53], P < .01). Optical coherence tomography angiography (OCTA) revealed reduced vessel density and enlarged foveal avascular zone in subjects with COVID-19 compared to controls.

CONCLUSIONS

The results suggested that COVID-19-related retinal microvasculopathy is a significant ocular manifestation of COVID-19 and may herald future retinal complications. These microvascular impairments might have occurred antecedent to clinically visible changes and could be detected earlier by OCTA. These findings are significant, due to the large numbers with COVID-19, and need to be recognized by ophthalmologists as a potential long-term sequalae of the disease.

Retinal findings of COVID-19 patients using Ocular coherence tomography angiography two to three months after infection: Ocular appearance recovered COVID-19 patient

Purpose

The aim of this study was to evaluate the ocular disorders in COVID-19 patients, two to three months after infection.

Methods

In this cross-sectional, historically controlled study, fifty-one COVID-19 patients were compared with thirty-seven age, and gender-matched healthy individuals. After complete ophthalmological examination, all participants underwent peripapillary and macular optical coherence tomography, and optical coherence tomography angiography (OCTA) measurements (OptoVue Inc, Freemont, CA, USA).

Results

The time between the initial onset of symptoms, and ophthalmologic examination was 63.31±15.21 (40–95 days). Ophthalmic examination of all the recovered COVID-19 patients was within normal range. None of the peripapillary and macular OCTA parameters were significantly different between the two groups with pairwise comparisons, but after adjusting for age, gender, axial length, and signal strength index (SSI), recovered COVID-19 eyes showed a significant increase in peripapillary retinal nerve fiber (RNFL) thickness, superficial, and deep macular vessel densities in parafoveal and perifoveal regions compared with healthy control eyes (p<= 0.05). Inner retinal thickness overall is higher in recovered COVID-19 eyes compared to healthy eyes after adjustment.

Conclusion

Patients with moderate-intensity SARS-CoV-2 pneumonia had altered peripapillary and macular vessel density compared to healthy subjects. Further investigation is warranted to analyze the correlation of these changes with disease severity as well as evolution of these changes over time.