Retinal vascular occlusions in COVID-19 infection and vaccination: a literature review

The Review of Ophthalmic Symptoms in COVID-19

The COVID-19 pandemic caused by SARS-CoV-2 had a significant impact on the health of the global human population, affecting almost every human organ, including the organ of vision. Research focus on understanding the pathophysiology, identifying symptoms and complications of the disease. Eye-related pathologies are important foci of research due to the potential for direct impact of the virus. Ophthalmologists around the world are reporting various symptoms of eye infections and ocular pathologies associated with SARS-CoV-2. The review of ophthalmic symptoms was conducted to help physicians of various specialties recognize possible ophthalmic manifestations of this viral disease. A literature review was conducted from January 2020 to July 2023 in the PubMed, MEDLINE, Science Direct, Scopus, Scielo and Google Scholar databases. The review of the literature showed that conjunctivitis is the most common ophthalmic symptom observed during the course of COVID-19 and can occur at any stage of the disease. Changes in the eye may result from the direct effect of the virus, immune response, prothrombotic states, comorbidities, and medications used. Symptoms related to the organ of vision can be divided into: changes affecting the protective apparatus of the eye, the anterior eye segment, the posterior eye segment, neuro-ophthalmic, and orbital changes. Ocular symptoms may suggest COVID-19 infection or appear several weeks after recovery. Following COVID-19 vaccinations, a diverse range of ophthalmic symptoms was observed in various locations and at different times, mirroring the ocular symptoms experienced throughout the course of the COVID-19 illness. It is important for physicians of all specialties to be aware of possible potential connections between eye diseases and SARS-CoV-2, in order to effectively diagnose and treat patients.

Branch retinal artery occlusion with unruptured retinal arterial macroaneurysm post-SARS-CoV-2 vaccination: A case report

INTRODUCTION

Many adverse occurrences in the eye have been reported after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination. This is the first report of a patient with an unruptured retinal arterial macroaneurysm (RAM) who developed branch retinal artery occlusion (BRAO) one day after SARS-CoV-2 vaccination (BNT162b2 by Pfizer-BioNTech).

PATIENT REPORT

A 75-year-old man with a pertinent history of type-2 diabetes mellitus visited the hospital complaining of sudden visual loss in his right eye 1 day after receiving the fourth dose of the SARS-CoV-2 mRNA vaccine; his best-corrected visual acuity (BCVA) decreased from 1.0 to 0.7 (Snellen decimal). The patient had previously been diagnosed with an unruptured RAM and superior paracentral acute middle maculopathy in the same eye. Fundus examination showed increased sheathing of blood vessels. Indocyanine green showed a hyperfluorescent area suggestive of RAM on the right eye disc. Fluorescein angiography and optical coherence tomography angiography revealed arterial obstruction findings in the upper retinal area.

DIAGNOSIS AND INTERVENTION

The patient was diagnosed with BRAO with RAM and was followed up without any additional treatment. Follow-up examination after 4 months did not show any improvement in BCVA value.

CONCLUSION

This case suggested that BRAO could develop after SARS-CoV-2 vaccination in patients with unruptured RAM; however, more research is required to investigate the causes.

SARS-CoV-2 infects cells lining the blood-retinal barrier and induces a hyperinflammatory immune response in the retina via systemic exposure

SARS-CoV-2 has been shown to cause wide-ranging ocular abnormalities and vision impairment in COVID-19 patients. However, there is limited understanding of SARS-CoV-2 in ocular transmission, tropism, and associated pathologies. The presence of viral RNA in corneal/conjunctival tissue and tears, along with the evidence of viral entry receptors on the ocular surface, has led to speculation that the eye may serve as a potential route of SARS-CoV-2 transmission. Here, we investigated the interaction of SARS-CoV-2 with cells lining the blood-retinal barrier (BRB) and the role of the eye in its transmission and tropism. The results from our study suggest that SARS-CoV-2 ocular exposure does not cause lung infection and moribund illness in K18-hACE2 mice despite the extended presence of viral remnants in various ocular tissues. In contrast, intranasal exposure not only resulted in SARS-CoV-2 spike (S) protein presence in different ocular tissues but also induces a hyperinflammatory immune response in the retina. Additionally, the long-term exposure to viral S-protein caused microaneurysm, retinal pigmented epithelium (RPE) mottling, retinal atrophy, and vein occlusion in mouse eyes. Notably, cells lining the BRB, the outer barrier, RPE, and the inner barrier, retinal vascular endothelium, were highly permissive to SARS-CoV-2 replication. Unexpectedly, primary human corneal epithelial cells were comparatively resistant to SARS-CoV-2 infection. The cells lining the BRB showed induced expression of viral entry receptors and increased susceptibility towards SARS-CoV-2-induced cell death. Furthermore, hyperglycemic conditions enhanced the viral entry receptor expression, infectivity, and susceptibility of SARS-CoV-2-induced cell death in the BRB cells, confirming the reported heightened pathological manifestations in comorbid populations. Collectively, our study provides the first evidence of SARS-CoV-2 ocular tropism via cells lining the BRB and that the virus can infect the retina via systemic permeation and induce retinal inflammation.

Aetiology, Diagnosis and Treatment of Arterial Occlusions of the Retina-A Narrative Review

Arterial occlusions of the retina are potentially sight-threatening diseases which often result in profound visual loss. The aim of this narrative review is to provide an overview of the aetiology, discuss major risk factors, describe the management and systemic assessments and evaluate existing therapies. For this review, an extensive literature search in PubMed was performed. Emboli from the heart or the carotid arteries can cause ophthalmic artery occlusion (OAO), central retinal artery occlusion (CRAO) and branch retinal artery occlusion (BRAO). Most patients with arterial occlusions have vascular risk factors such as arterial hypertension, hyperhomocysteinaemia, carotid stenosis and atrial fibrillation, which also increase the risk of cerebral stroke and myocardial infarction. Therapies such as ocular massage, thrombolysis and anterior chamber paracentesis have been suggested but are still equivocal. However, it is evident that retinal artery occlusion should be immediately treated and accompanied by interdisciplinary collaboration, since early diagnosis and the proper treatment of possible risk factors are important to reduce the risk of further damage, recurrences, other vascular diseases and mortality.

Retinal Artery and Vein Occlusion Risks after Coronavirus Disease 2019 or Coronavirus Disease 2019 Vaccination

PURPOSE

To evaluate the incidence of new retinal artery occlusion (RAO) and retinal vein occlusion (RVO) after the diagnosis of coronavirus disease 2019 (COVID-19) or vaccination against COVID-19 and compare the incidences with the population with neither.

DESIGN

Nationwide population-based cohort study.

PARTICIPANTS

From a nationwide population-based cohort, 8 418 590 patients were categorized into control (group 1), COVID-19 infection (group 2), and COVID-19 vaccination (group 3) groups.

METHODS

The cumulative incidence of RAO and RVO was calculated in groups 1, 2, and 3 using the Kaplan-Meier method. We calculated hazard ratios (HRs) and 95% confidence intervals (CIs) based on the Poisson distribution for RAO and RVO according to each group and subgroup using Cox proportional hazards models, with group 1 as the reference. We conducted univariable and multivariable analyses for the risk factors of RAO and RVO according to each subgroup.

MAIN OUTCOME MEASURES

Cumulative incidence and risks of incidence of RAO and RVO from the index date to day 60.

RESULTS

In multivariable analysis, no significant increase in RAO and RVO risks after COVID-19 or COVID-19 vaccination were observed in either men or women. These results were observed consistently across various conditions in sensitivity analyses. In subgroup analysis, individuals who were vaccinated before infection showed no significant increase in RAO or RVO risks in both sexes compared with the control group. In the subgroup analysis of vaccinated patients, the HRs of RAO and RVO for different vaccine types did not show an increase compared with the control group; however, an exception was observed in women who received mRNA-1273 vaccines, who showed a higher RAO HR (4.65; 95% CI, 1.27-17.03; P = 0.021).

CONCLUSIONS

Within 60 days of COVID-19 diagnosis or vaccination, RAO and RVO occurred rarely. We observed no increase in the HR of RVO and RAO relative to COVID-19 or COVID-19 vaccination except for a possible increase in the RAO HR in women who received mRNA-1273, for which the raw incidence was extremely low. Further investigation is required to validate this result.

FINANCIAL DISCLOSURE(S)

The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Isolated Depo-Medrol Administration under Tenon's Capsule for Post-COVID-19 Uveitis in a Child: A Case Report and Literature Review

Coronavirus disease 2019 (COVID-19) can manifest with ocular symptoms. These symptoms can be divided into isolated events attributed to COVID-19, and those occurring in multisystem inflammatory syndrome in children (MIS-C), a newly diagnosed disease entity associated with COVID-19 infection. Currently, the literature lacks specific guidelines and treatment regimens for COVID-19 ocular symptoms, especially in children. The authors present the case of a 14-and-a-half-year-old boy with bilateral uveitis of the anterior and posterior segments along with vasculitis and optic neuritis associated with SARS-CoV-2 infection. The authors also perform an up-to-date review of all available publications on the treatment of post-COVID-19 uveitis in children described in the literature between 2020 and 2023. In the case described by the authors, the treatment involved a Depo-Medrol 40 mg/mL injection uder the Tenon capsule, with two subconjunctival injections of epinephrine, topical steroid therapy and non-steroidal anti-inflammatory drugs: dexamethasone 0.1%; diclofenac eye drops. In addition, acetylsalicylic acid (150 mg) and pentoxifylline (100 mg, orally) were administered throughout the course of the disease as well as up to 12 months after its termination, until a complete improvement in visual acuity and the withdrawal of ocular lesions were achieved. It can be assumed that this type of treatment is far more beneficial for pediatric patients, with an effect comparable to systemic steroid administration with a preserved improvement in retinal-vascular circulation, without exposing the child to systemic post-steroid complications.

A case of IgG4-related ophthalmic disease after SARS-CoV-2 vaccination: case report and literature review

Coronavirus disease 19 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is affecting the world with a surge in cases. A variety of autoimmune diseases occur after SARS-CoV-2 infection or vaccination, of which IgG4-related disease (IgG4-RD) is an important type. IgG4-RD can involve multiple organs of the body. The ocular manifestation of IgG4-RD is called IgG4-related ophthalmic disease (IgG4-ROD). We herein report a patient diagnosed with IgG4-ROD. The patient developed ptosis and vision loss after SARS-CoV-2 vaccination, and the symptoms worsened after SARS-CoV-2 infection. After excluding other diseases like myasthenia gravis and Eaton-Lambert syndrome that may cause ptosis, the diagnosis of IgG4-ROD was confirmed by pathological examination. We discussed the predisposing factors, diagnosis and treatment of this patient to provide a more empirical and theoretical basis for clinical diagnosis and treatment. We conducted a literature review of previously reported cases of IgG4-RD following SARS-CoV-2 infection or vaccination. We retrieved a total of 9 cases, of which 5 developed symptoms after vaccination and 4 after infection. Demographic and clinical characteristics were summarized. In conclusion, our case represents the first case of proven IgG4-ROD after COVID-19 vaccination. We believe that IgG4-ROD and SARS-CoV-2 infection or vaccination are closely related, and the immune system disorder caused by SARS-CoV-2 infection or vaccination may be a key factor in the pathogenesis of IgG4-RD. But for now, there is no direct evidence that there is a causal relationship between SARS-CoV-2 infection or vaccination and IgG4-ROD, which still needs more research and exploration to confirm.

Infectious eye disease in the 21st century-an overview

Infectious diseases affecting the eye often cause unilateral or asymmetric visual loss in children and people of working age. This group of conditions includes viral, bacterial, fungal and parasitic diseases, both common and rare presentations which, in aggregate, may account for a significant portion of the global visual burden. Diagnosis is frequently challenging even in specialist centres, and many disease presentations are highly regional. In an age of globalisation, an understanding of the various modes of transmission and the geographic distribution of infections can be instructive to clinicians. The impact of eye infections on global disability is currently not sufficiently captured in global prevalence studies on visual impairment and blindness, which focus on bilateral disease in the over-50s. Moreover, in many cases it is hard to differentiate between infectious and immune-mediated diseases. Since infectious eye diseases can be preventable and frequently affect younger people, we argue that in future prevalence studies they should be considered as a separate category, including estimates of disability-adjusted life years (DALY) as a measure of overall disease burden. Numbers of ocular infections are uniquely affected by outbreaks as well as endemic transmission, and their control frequently relies on collaborative partnerships that go well beyond the remit of ophthalmology, encompassing domains as various as vaccination, antibiotic development, individual healthcare, vector control, mass drug administration, food supplementation, environmental and food hygiene, epidemiological mapping, and many more. Moreover, the anticipated impacts of global warming, conflict, food poverty, urbanisation and environmental degradation are likely to magnify their importance. While remote telemedicine can be a useful aide in the diagnosis of these conditions in resource-poor areas, enhanced global reporting networks and artificial intelligence systems may ultimately be required for disease surveillance and monitoring.

Acute macular neuroretinopathy and COVID-19 or SARS-CoV-2 infection: case report and literature review

Purpose

To describe a case of acute macular neuroretinopathy (AMN) associated with COVID-19 infection and a related literature review.

Methods

A case from the First Affiliated Hospital of Chongqing Medical University was reported that could be linked to COVID-19 or SARS-CoV-2 infection. We performed a comprehensive search on PubMed, retrieving articles containing information on AMN after COVID-19 or SARS-CoV-2 infection. The key words used were 'COVID-19', 'SARS-CoV-2', 'ophthalmic manifestations', 'acute macular neuroretinopathy', and 'paracentral scotomas'. The relevant data were extracted, charted, consolidated, and evaluated. Moreover, manual exploration of the reference lists of pertinent articles was carried out.

Results

We describe the case of a 30-year-old young woman who developed bilateral AMN one day after being infected with COVID-19 or SARS-CoV-2. She had severe visual impairment (20/2000 OD and 20/32 OS), and her vision recovered after taking oral corticosteroids. After reviewing the literature, we summarized 16 relevant reports and found that symptoms of AMN tend to arise 1 day to 1 month after COVID-19 or SARS-CoV-2 infection. Contraceptive pills and other risk factors should be avoided to reduce the risk of adverse outcomes. Oral prednisone may be an effective treatment for those experiencing important vision loss.

Conclusion

Symptoms of AMN can arise 1 day to 1 month after COVID-19 or SARS-CoV-2 infection. Ophthalmologists should remain vigilant about this disease, notably because patient characteristics may deviate from the norm.

RETINAL VASCULAR OCCLUSION AND COVID-19 DIAGNOSIS: A Multicenter Population-Based Study

BACKGROUND

Several ocular diseases have been reported in patients with coronavirus disease 2019 (COVID-19), especially retinal vascular occlusion. This study aimed to examine the risk of retinal vascular occlusion after COVID-19 diagnosis.

METHODS

This retrospective cohort study was based on 46 health care organizations in the United States using the TriNetX network. Individuals who had laboratory confirmation of COVID-19 from January 1, 2020, to December 31, 2021, were included. Multivariate analysis was adjusted on age, sex, race, and comorbidities, and hazard ratio was calculated using the Cox proportional hazard regression model.

RESULTS

A total of 1,460,634 paired individuals were enrolled for analysis. Patients with COVID-19 had a significantly higher risk of branch retinal vein occlusion (hazard ratio 1.27, 95% confidence interval [CI] 1.04-1.52) than those without COVID-19. The cumulative incidence rate of branch retinal vein occlusion was also significantly higher in patients with COVID-19 compared with those without COVID-19 (log-rank P = 0.014). Within 12 weeks after COVID-19 diagnosis, the transient effect of central retinal vein occlusion (hazard ratio 1.59, 95% confidence interval 1.15-2.17) and branch retinal vein occlusion (hazard ratio 2.11, 95% confidence interval 1.51-2.95) were observed.

CONCLUSION

This large-scale multicenter study demonstrated that retinal vein occlusion may be associated with COVID-19.

Ocular Complications after COVID-19 Vaccination: A Systematic Review

Background and Objectives: The COVID-19 pandemic affects various populations worldwide. The discovery of vaccinations was necessary for the prevention and elimination of the disease. Despite the high importance of these vaccinations, they may cause some complications, such as ocular complications. This study aims to draw attention to the possible complications of the vaccination and highlight its importance. Materials and Methods: Systematic review of the literature from January 2021 to January 2023. A total of 20 published articles were included and reported cases of ocular complications in patients who received COVID-19 vaccines. Results: A total of 243 patients with verified ocular complications following the COVID-19 vaccination were included, ranging in age from 18 to 84 years. The most common ocular complications reported in the current study were ocular inflammatory complications, which represented 47.3%, followed by optic neuritis (24.3%). Retinal artery occlusion, retinal vein occlusion, acute macular neuroretinopathy, and paracentral acute middle maculopathy represented 10.7%. Herpetic ocular infections and herpetic eye disease (14%). Nearly half (42%) of the patients with ocular problems received the Pfizer-BioNTech vaccination. Conclusions: Despite the high importance of the COVID-19 vaccination, it was found that it is associated with the occurrence of some ocular complications. Future projects should come with more extensive prospective studies to further elucidate the underlying mechanisms and risk factors associated with ocular complications following COVID-19 vaccination, thereby enhancing our understanding and guiding appropriate management strategies.

Do we need more guidance on thrombophilia testing? Challenges and special considerations

INTRODUCTION

Thrombophilia testing (TT) is a laboratory procedure designed to detect the risk factors involved in the pathogenesis of vascular occlusions. The role of TT is also controversial because it has a limited impact on the choice and duration of antithrombotic treatments.

AREAS COVERED

We reviewed, by examining MEDLINE up to October 2023. Accepted and not accepted thrombophilia markers are discussed along with the appropriateness or not of prescribing TT in several conditions such as: provoked and unprovoked venous thromboembolism (VTE), women who are planning a pregnancy whose relatives had VTE or have a hereditary thrombophilia, before assumption of estro-progestins, after multiple pregnant loss, arterial thrombosis, retinal vein occlusion, and splanchnic vein thrombosis.

EXPERT OPINION

TT is not essential in the management of VTE, but it may be useful for limiting adverse events in case of thrombophilia. We expose our criticism of items afforded by other guidelines by presenting our opinion based on both the scientific evidence and clinical practice. We also deal with common mistakes in prescribing and interpretations of TT hoping to purpose an educational approach on this topic. Finally, we emphasize the creation of the expert in hemostasis and thrombosis who should be present in every hospital.

Recovery From Central Retinal Artery Occlusion Accompanying Paracentral Acute Middle Maculopathy After COVID-19 Vaccination

Although ocular complications following COVID-19 vaccination have been reported, particularly retinal vascular occlusion and uveitis, their definitive causal relationships remain uncertain. This report presents a case of central retinal artery occlusion (CRAO) with paracentral acute middle maculopathy (PAMM) developed one day after receiving Pfizer COVID-19 vaccine, with a favorable outcome. The patient experienced sudden vision loss in her left eye, and her vision dropped to hand motion the day after vaccination. The initial examination suggested CRAO, but optical coherence tomography (OCT) revealed PAMM. We administered intravenous d-mannitol and acetazolamide and performed ocular massage. Two days later, her corrected visual acuity improved to 0.4, and further improvement to 1.2 occurred after 16 days. To the best of our knowledge, no reports have documented CRAO with PAMM following mRNA COVID-19 vaccination. The relationship between COVID-19 vaccination and retinal vascular occlusion remains unknown, highlighting the need for further research.

Acute Macular Neuroretinopathy after SARS-CoV-2 Infection: An Analysis of Clinical and Multimodal Imaging Characteristics

BACKGROUND

This study aimed to analyze clinical and multimodal imaging characteristics of acute macular neuroretinopathy (AMN) post-recent severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection.

METHODS

Retrospective observational study. Medical records and multimodal imaging of 12 AMN eyes of eight patients (six female and two male) with recent SARS-CoV-2 infection were retrospectively analyzed.

RESULTS

Four patients (50%) presented with bilateral AMN. Fundus ophthalmoscopy revealed a reddish-brown lesion around the macula, and two eyes had cotton-wool spots at the posterior pole. Three eyes showed mild hypo-autofluorescence. All FFA images (7 eyes) showed no abnormal signs. On OCT scans, all eyes showed outer nuclear layer (ONL) thinning, 8 eyes (66.7%) showed ONL hyperreflectivity, 5 eyes (41.7%) showed outer plexiform layer (OPL) hyperreflectivity, 8 eyes (66.7%) showed interdigitation zone (IZ) disruption, 11 eyes (91.6%) showed ellipsoid zone (EZ) disruption, 2 eyes (16.7%) showed cotton-wool spots and inner plexiform layer (IPL) hyperreflectivity, 1 eye (8.3%) had intraretinal cyst and 1 eye (8.3%) had inner nuclear layer (INL) thinning. Persistent scotoma, ONL hyperreflectivity and IZ/EZ disruption as well as recovery of OPL hyperreflectivity were reported after follow-up in three cases.

CONCLUSIONS

AMN post-SARS-CoV-2 mostly affected young females and could present unilaterally or bilaterally. Dark lesions on IR reflectance and outer retinal hyperreflectivity on OCT are useful in diagnosing AMN. OPL/ONL hyperreflectivity on OCT could disappear after follow-up, but ONL thinning and IZ/EZ could persist.

Paracentral Acute Middle Maculopathy Following Acute Primary Angle Closure and Acute Primary Angle Closure Glaucoma

Purpose

To report the prevalence, clinical characteristics and risk factors for paracentral acute middle maculopathy (PAMM) following acute primary angle closure (APAC) and acute primary angle closure glaucoma (APACG).

Methods

This retrospective study consecutively recruited patients diagnosed with APAC or APACG. Based on the spectral domain optical coherence tomography characteristics, PAMM eyes were divided into three stages. Characteristics of different stages such as the time from symptoms to treatment (TST), retinal thickness and BCVA improvement were analyzed. The risk factors of PAMM were evaluated by binary logistic regression models.

Results

A total of 781 eyes of 781 APAC or APACG patients were included, and PAMM was found in 22 (2.9%) of them. Stage III eyes had a significantly longer TST than stage I eyes (P = 0.008) while exhibiting significantly thinner retinal thicknesses (P < 0.0001). The BCVA improvement was significantly worse in the eyes treated in stage III than in those treated in stage I (P = 0.008). Older age, longer axial length and without type 2 diabetes were associated with a lower risk of incident PAMM (OR = 0.95, P = 0.028; OR = 0.52, P = 0.019; OR = 3.92, P = 0.022).

Conclusion

PAMM can be secondary to APAC or APACG at a rate of 2.9%. Different visual outcomes were observed in patients who received the intervention at different stages of PAMM. Younger patients with a shorter axial length and type 2 diabetes were found to be more susceptible to PAMM.

COVID-19 and Alzheimer's Disease Share Common Neurological and Ophthalmological Manifestations: A Bidirectional Risk in the Post-Pandemic Future

A growing body of evidence indicates that a neuropathological cross-talk takes place between the coronavirus disease 2019 (COVID-19) -the pandemic severe pneumonia that has had a tremendous impact on the global economy and health since three years after its outbreak in December 2019- and Alzheimer's Disease (AD), the leading cause of dementia among human beings, reaching 139 million by the year 2050. Even though COVID-19 is a primary respiratory disease, its causative agent, the so-called Severe Acute Respiratory Syndrome coronavirus 2 (SARS-CoV-2), is also endowed with high neuro-invasive potential (Neurocovid). The neurological complications of COVID-19, resulting from the direct viral entry into the Central Nervous System (CNS) and/or indirect systemic inflammation and dysregulated activation of immune response, encompass memory decline and anosmia which are typically associated with AD symptomatology. In addition, patients diagnosed with AD are more vulnerable to SARS-CoV-2 infection and are inclined to more severe clinical outcomes. In the present review, we better elucidate the intimate connection between COVID-19 and AD by summarizing the involved risk factors/targets and the underlying biological mechanisms shared by these two disorders with a particular focus on the Angiotensin-Converting Enzyme 2 (ACE2) receptor, APOlipoprotein E (APOE), aging, neuroinflammation and cellular pathways associated with the Amyloid Precursor Protein (APP)/Amyloid beta (Aβ) and tau neuropathologies. Finally, the involvement of ophthalmological manifestations, including vitreo-retinal abnormalities and visual deficits, in both COVID-19 and AD are also discussed. Understanding the common physiopathological aspects linking COVID-19 and AD will pave the way to novel management and diagnostic/therapeutic approaches to cope with them in the post-pandemic future.

Update on coronavirus disease 2019: Ophthalmic Manifestations and Adverse Reactions to Vaccination

The coronavirus disease 2019 (COVID-19) pandemic caused by the severe acute respiratory syndrome coronavirus 2 was one of the most devastating public health issues in recent decades. The ophthalmology community is as concerned about the COVID-19 pandemic as the global public health community is, as COVID-19 was recognized to affect multiple organs in the human body, including the eyes, early in the course of the outbreak. Ophthalmic manifestations of COVID-19 are highly variable and could range from mild ocular surface abnormalities to potentially sight and life-threatening orbital and neuro-ophthalmic diseases. Furthermore, ophthalmic manifestations may also be the presenting or the only findings in COVID-19 infections. Meanwhile, global vaccination campaigns to attain herd immunity in different populations are the major strategy to mitigate the pandemic. As novel vaccinations against COVID-19 emerged, so were reports on adverse ophthalmic reactions potentially related to such. As the world enters a post-pandemic state where COVID-19 continues to exist and evolve as an endemic globally, the ophthalmology community ought to be aware of and keep abreast of the latest knowledge of ophthalmic associations with COVID-19 and its vaccinations. This review is a summary of the latest literature on the ophthalmic manifestations of COVID-19 and the adverse ophthalmic reactions related to its vaccinations.

Blood Coagulation and Thrombotic Disorders following SARS-CoV-2 Infection and COVID-19 Vaccination

Although abundant data confirm the efficacy and safety profile of the developed vaccines against COVID-19, there are still some concerns regarding vaccination in high-risk populations. This is especially valid for patients susceptible to thrombotic or bleeding events and hesitant people due to the fear of thrombotic incidents following vaccination. This narrative review focuses on various inherited and acquired thrombotic and coagulation disorders and the possible pathophysiologic mechanisms interacting with the coagulation system during immunization in view of the currently available safety data regarding COVID-19 vaccines. Inherited blood coagulation disorders and inherited thrombotic disorders in the light of COVID-19, as well as blood coagulation and thrombotic disorders and bleeding complications following COVID-19 vaccines, along with the possible pathogenesis hypotheses, therapeutic interventions, and imaging for diagnosing are discussed in detail. Lastly, the lack of causality between the bleeding and thrombotic events and COVID-19 vaccines is debated, but still emphasizes the importance of vaccination against COVID-19, outweighing the minimal risk of potential rare adverse events associated with coagulation.

Acute-Onset Retinal Conditions Mimicking Acute Optic Neuritis: Overview and Differential Diagnosis

Acute optic neuritis (AON) is a common cause of sudden visual loss in young patients. Because of the risk of demyelinating disease, patients affected by unilateral or bilateral optic neuritis should be evaluated and treated accordingly. Despite advancements in imaging of the brain and retina, misdiagnosis of AON is not uncommon. Indeed, some acute disorders of the retina have the potential to mimic AON and their prompt diagnosis may avoid unnecessary neurologic investigation, psychological stress to the patient, and delays in treatment. This review describes uncommon retinal disorders presenting with sudden-onset visual loss and absent or subtle funduscopic manifestation that can mimic AON. Multimodal retinal imaging is essential in detecting these conditions and in their differential diagnosis. It behooves neurologists and general ophthalmologists to be aware of these entities and be familiar with multimodal imaging of the retina.

Retinal Vein Occlusion after COVID-19 Vaccination-A Review

Background Retinal vein occlusion (RVO) occurring after COVID-19 vaccination has been reported worldwide. Such a sight-threatening condition occurring after COVID-19 vaccination is a menace to ophthalmic health. This article reviews current evidence related to post-COVID-19 vaccination RVO. Method A total of 29 relevant articles identified on PubMed in January 2023 were selected for review. Observation All cases presented to ophthalmologists with visual loss shortly after COVID-19 vaccination. Mean and median age were both 58. No sex predominance was observed. RVO was diagnosed from findings on dilated fundal examination and ophthalmic imaging. AstraZeneca and BNT vaccines accounted for most cases. Vascular risk factors, e.g., diabetes mellitus and hypertension, were common. Most laboratory tests requested came back unremarkable. Most patients responded well to standard treatment, except those with ophthalmic comorbidities. Visual prognosis was excellent on short-term follow-up. Discussion The causality between RVO and COVID-19 vaccination is undeterminable because of the nature of articles, heterogenous reporting styles, contradicting laboratory findings and co-existing vascular risk factors. Vaccine-induced immune thrombotic thrombocytopenia, retinal vasculitis and homocysteinaemia were proposed to explain post-vaccination RVO. Large-scale studies have demonstrated that the incidence of RVO following COVID vaccination is very low. Nevertheless, the effects of boosters on retinal vasculature and ophthalmic health are still unclear. Conclusions The benefits of COVID-19 vaccination are believed to outweigh its ophthalmic risks. To ensure safe vaccination, the prior optimisation of comorbidities and post-vaccination monitoring are important. COVID-19 vaccines (including boosters) should be offered with reasonable confidence. Further studies are warranted to elucidate the ophthalmic impact of vaccines.

Retinal vascular occlusion following SARS-CoV-2 vaccination: A VAERS database analysis

Purpose

To evaluate the cases of retinal vessel occlusion following COVID-19 vaccination and evaluate the onset interval and clinical presentations in patients diagnosed with vaccine associated retinal artery occlusion (RAO) and retinal vein occlusion (RVO).

Design

Retrospective study of the cases reported to the Centers for Disease Control and Prevention (CDC) Vaccine Adverse Events Reporting System (VAERS) between December 11, 2020 and July 1, 2022.

Participants

Patients diagnosed with retinal vessel occlusion following vaccination with BNT162b2, mRNA-1273, and Ad26.COV2.S globally.

Methods

We performed a descriptive analysis of the patient demographics and clinical presentation in patients with retinal vessel occlusion. The correlation between the vaccines and continuous and categorical variables were assessed. We performed the post-hoc analysis to evaluated the association between RAO and RVO onset post-vaccination, and vaccine and dosage. Finally, a 30-day reverse analysis for RAO and RVO onset following administration of vaccine. A major limitation in the methods of this study is the lack of control group for assessing the risk of retinal vessel occlusive disease in patients who received the vaccine compared to the patients who were unvaccinated.

Main Outcome Measures

The crude reporting rate of retinal vessel occlusion following SARS-CoV-2 vaccine. The ocular and systemic presentations, onset duration and short term risk of RAO and RVO following vaccination.

Results

During the study period, 1351 retinal vessel occlusion cases were reported globally. The crude reporting rates of retinal vessel occlusion for BNT162b2, mRNA-1273, and Ad26.COV2.S were 0.36, 0.41, and 0.69, respectively. The majority of the retinal vessel occlusion cases were reported following BNT162b2 (n=606, 74.17%). The mean age of patients with RVO and RAO was 58.54 ± 16.06 years and 64.63 ± 16.16 years, respectively. In the cohort, 817 and 433 patients were diagnosed with RVO and RAO, respectively. Most cases of RVO (41.12%) and RAO (48.27%) were reported within the first week post-vaccination. We observed that the mean onset interval for RVO was significantly longer in patients who received Ad26.Cov2.S (54.07 ± 88.98 days) compared to BNT162b2 (18.07 ± 28.66 days) and mRNA-1273 (22.85 ± 38.13 days) vaccines (p<0.0001). This was further confirmed by post-hoc analysis, which revealed a significantly longer onset duration for the Ad26.Cov2.S compared to BNT162b2 and mRNA 1273 vaccines (p<0.0001). The reverse Kaplan Meier 30-day risk analysis showed a significant a higher risk of RVO onset following BNT162b2 compared to other vaccines(p<0.0001).

Conclusions

The low crude reporting rate highlights a low safety concern for retinal vessel occlusion following SARS-CoV-2 vaccination. This study provides insights into possible temporal association between reported retinal vessel occlusion events with SARS-CoV-2 vaccines, however further insights are needed to understand the underlying immunopathological mechanisms that promote thrombosis of retinal vasculature on vaccine administration.