Search Results (13)

Background: Retinal vascular occlusion (RVO) and retinal artery occlusion (RAO) have been reported as rare adverse events following COVID-19 vaccination, raising concerns about vaccine safety. This review synthesizes cohort and case–control studies assessing the association between COVID-19 vaccines and RVO/RAO, while exploring potential pathophysiological mechanisms. Methods: We analyzed large-scale population-based studies from South Korea, Europe, and the TriNetX database, focusing on odds ratios (OR), hazard ratios (HR), and relative risks (RR) across mRNA and adenoviral vector vaccines. Pathological processes were hypothesized based on molecular and clinical evidence. Results: Studies investigating the association between COVID-19 vaccination and retinal vascular occlusion show conflicting results; some studies report no association (e.g., OR 0.93, 95% CI 0.60–1.45), others suggest reduced risk (e.g., OR 0.80, 95% CI 0.64–0.99), and one indicates increased risk over two years (HR 2.19, 95% CI 2.00–2.39). Adenoviral vector vaccines, particularly ChAdOx1, show higher RAO incidence in specific cohorts. Proposed mechanisms include vaccine-induced immune thrombotic thrombocytopenia (VITT) via anti-PF4 antibodies, spike protein-mediated endothelial dysfunction, and adjuvant-driven inflammation. Conclusions: While causality remains unproven, temporal heterogeneity and vaccine type-specific risks warrant further investigation. Longitudinal studies with robust controls are needed to clarify these associations in the post-pandemic context. Full article

Background/Objectives: To provide insight into populations at higher risk of COVID-19-related retinal vascular occlusion, we identified the baseline characteristics of COVID-19 patients and vaccine recipients who developed this condition by conducting a systematic review to summarize the findings and evaluate the current knowledge on this subject. Methods: An electronic search on the PubMed and Scopus databases was performed for relevant case reports or series regarding retinal vascular occlusion in patients with past or present COVID-19 infection or SARS-CoV-2 immunization. This study was conducted using a pre-determined protocol following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Results: A total of 34 studies were enrolled in this systematic review. A total of 21 patients (14 males, 66.7%) have been diagnosed with COVID-19 related retinal vein occlusion (RVO, mean age = 41.9 ± 10.3 years), and 15 patients (12 males, 80%) have been diagnosed with retinal artery occlusion (RAO, mean age = 56.9 ± 13.2 years). The time to RVO since COVID-19 infection or SARS-CoV-2 immunization ranged from 8 h to 51 days (mean = 12.3 ± 15.7 days), while the time to RAO ranged from 2 to 40 days (mean = 14.9 ± 10.8 days). Fifteen out of the twenty-one patients (71.4%) with RVO had a significant improvement in visual acuity after the resolution of symptoms while eight out of the fifteen patients (53.3%) with RAO did not show improvement. Conclusions: COVID-19 seems to play a significant role in the pathogenesis of vascular occlusion, as it is suggested to increase the risk of thromboembolic episodes. However, the pathophysiologic mechanisms have not been fully elucidated, and further studies are expected to shed light on this phenomenon. Full article

Background/Objectives: Retinal vascular occlusions, such as retinal vein occlusion (RVO) and retinal artery occlusion (RAO), are associated with cognitive impairment, including dementia. Our objective was to examine the odds of dementia among patients with retinal vascular occlusion. Methods: This cross-sectional study included 474 patients with retinal vascular occlusion and 948 patients without retinal vascular occlusion (comparison group). Patients in the comparison group were age- and sex-matched to those with vascular occlusion. Logistic regression was used to analyze the odds of all-cause dementia, vascular dementia, and Alzheimer’s disease after adjusting for demographic, clinical, and ophthalmic covariates. Main outcome measures included the presence of all-cause dementia, vascular dementia, and Alzheimer’s disease. Results: Patients with RVO (n = 413) had increased odds for all-cause dementia (odds ratio (OR) = 2.32; 95% confidence interval (CI): 1.44–3.75; p < 0.001) and vascular dementia (OR = 3.29; 95% CI: 1.41–7.68; p = 0.006) relative to the comparison group. Patients with central RVO (n = 192) (OR = 2.32; 95% CI: 1.19–4.54; p = 0.014) or branch RVO (n = 221) (OR = 2.68; 95% CI: 1.30–5.50; p = 0.007) had increased odds for all-cause dementia relative to the comparison group. Patients with RAO (n = 61) did not have increased odds of all-cause dementia (OR = 1.01; 95% CI: 0.32–3.26; p = 0.983), vascular dementia (OR = 1.54; 95% CI: 0.22–10.81; p = 0.663), or Alzheimer’s disease (OR = 0.32; 95% CI: 0.05–2.20; p = 0.244). Conclusions: A history of any RVO is associated with increased rates of all-cause dementia and vascular dementia independent of shared cardiovascular risk factors. These associations are not seen with a history of RAO, or between any subtype of vascular occlusions and Alzheimer’s disease. Full article

Retinal artery occlusion (RAO) is an emergency condition causing acute retinal ischemia and is considered an equivalent of ischemic stroke. The occurrence of an episode of RAO is associated with significant impairment of visual functions and correlates with an increased risk of future vascular events. Although RAO requires immediate diagnosis and treatment, there are currently no clear guidelines specifying optimal management. This review discusses current and future therapeutic strategies following an episode of RAO, including secondary prevention. Full article

Takayasu arteritis is a chronic inflammatory vasculitis with granulomatous panarteritis particularly impacting large vessels including the aorta and its branches, especially the subclavian arteries, with clinical manifestation dependent on the involved artery. Sequelae of the active disease vary, including stenosis, occlusions, or aneurysmal dilatations of the large vessels. The prevalence of Takayasu arteritis is higher in the Asian population and in Japan, but quite low in the United States, varying from 0.9–8.4 per million people. Ocular manifestations are rare and lead to a delay in diagnosis and appropriate treatment. Ocular manifestations include Takayasu retinopathy, anterior ischemic optic neuropathy (AION), retinal artery occlusion (RAO) and retinal vein occlusion (RVO). We present two cases in which central retinal artery occlusion (CRAO) was associated with Takayasu arteritis. CRAO is an ophthalmic emergency with an incidence of 1.9 per 100,000 person years in the United States; only 5% of cases are arteritic, which can be observed with inflammatory vasculitides secondary to the formation of immune deposits. Full article

Background and Objectives: We aimed to analyse data on retinal artery occlusion (RAO) patients to explore correlations with acute ischaemic stroke (AIS), ST-elevation myocardial infarction (STEMI), and cardio/cerebrovascular comorbidities. Patients and Methods: Our retrospective cohort study included 169 RAO and 169 age- and gender-matched control patients. We examined the association of AIS, STEMI, and related comorbidities such as hypertension (HT), type 1 and type 2 diabetes (T1DM and T2DM, respectively), hyperlipidaemia, and ischaemic heart disease (IHD) with RAO. We also recorded atrial fibrillation in our RAO patients. Results: Our results demonstrated that RAO patients developed both AIS and STEMI at a significantly higher rate compared to controls (p < 0.001 for both). We also found that RAO patients had a significantly higher prevalence of HT and hyperlipidaemia (p1 = 0.005, p2 < 0.001) compared to controls. Multiple risk factors together significantly increased the odds of developing AIS and STEMI. Conclusions: Our results suggest that through identifying and treating the risk factors for RAO patients, we can reduce the risk of AIS, STEMI, and RAO of the fellow eye. Considering that ophthalmologists are often the first detectors of these cardiovascularly burdened patients, collaboration with colleagues from internal medicine, cardiology, and neurology is essential to achieve secondary prevention. Full article

Retinal artery occlusion (RAO) is a devastating condition with no effective treatment. The management of RAO could potentially be improved through an in-depth understanding of the molecular alterations in the condition. This study combined advanced proteomic techniques and an experimental model to uncover the retinal large-scale protein profile of RAO. In 13 pigs, RAO was induced with an argon laser and confirmed by fluorescein angiography. Left eyes serving as controls received a sham laser without inducing occlusion. Retinal samples were collected after one, three, or six days and analyzed with liquid chromatography—tandem mass spectrometry. In RAO, 36 proteins were differentially regulated on day one, 86 on day three, and 557 on day six. Upregulated proteins included clusterin, vitronectin, and vimentin, with several proteins increasing over time with a maximum on day six, including clusterin, vimentin, osteopontin, annexin-A, signal transducer, and the activator of transcription 3. On day six, RAO resulted in the upregulation of proteins involved in cellular response to stress, hemostasis, innate immune response, and cytokine signaling. Downregulated proteins were involved in transmission across chemical synapses and visual phototransduction. This study identified the upregulation of multiple inflammatory proteins in RAO and the downregulation of proteins involved in visual pathways. Full article

Retinal artery occlusion (RAO) is most commonly caused by embolism. Evidence showed that hematocrit (Hct) levels are often associated with embolic events. In this study, we aim to investigate the relationship between Hct levels and RAO. This retrospective study enrolled RAO patients between January 2011 and March 2020, who were 1:4 matched by age, gender, index date, and relevant comorbidities with the non-RAO group. Patient characteristics and laboratory data were collected. Univariate conditional logistic regression was applied by estimating crude matched odds ratios to determine the relevant factors for the occurrence of RAO. Furthermore, a narrative review of the relevant study was conducted to explore the association between Hct levels and embolism. Between January 2011 to March 2020, 82 RAO patients and 328 non-RAO patients matched with age, gender, index date, comorbidities of hypertension, diabetes mellitus, dyslipidemia, chronic kidney disease, stroke, and atrial fibrillation were enrolled after excluding ineligible individuals. Conditional logistic regression analysis showed that Hct level ≥ 40% was associated with developing RAO. A forest plot showed a trend of a non-linear dose-response association between Hct levels and ischemic vascular events in male patients. Hct levels ≥ 40% in patients older than 65 years with at least six comorbidities could be associated with RAO. We suggest that older patients who have multiple comorbidities, combined with elevated Hct levels, should be informed of the possible occurrence of RAO. Full article

Traditional dilated ophthalmoscopy can reveal diseases, such as age-related macular degeneration (AMD), diabetic retinopathy (DR), diabetic macular edema (DME), retinal tear, epiretinal membrane, macular hole, retinal detachment, retinitis pigmentosa, retinal vein occlusion (RVO), and retinal artery occlusion (RAO). Among these diseases, AMD and DR are the major causes of progressive vision loss, while the latter is recognized as a world-wide epidemic. Advances in retinal imaging have improved the diagnosis and management of DR and AMD. In this review article, we focus on the variable imaging modalities for accurate diagnosis, early detection, and staging of both AMD and DR. In addition, the role of artificial intelligence (AI) in providing automated detection, diagnosis, and staging of these diseases will be surveyed. Furthermore, current works are summarized and discussed. Finally, projected future trends are outlined. The work done on this survey indicates the effective role of AI in the early detection, diagnosis, and staging of DR and/or AMD. In the future, more AI solutions will be presented that hold promise for clinical applications. Full article

The aim of the study was to evaluate the incidence of ischemic stroke, myocardial infarction, and all-cause mortality in patients with retinal artery occlusion (RAO). This single-center retrospective study included 139 patients diagnosed with RAO between 2009 and 2020. The control group included 139 age- and sex-matched patients without RAO who underwent cataract surgery. The year of the surgery corresponded to the year of RAO onset. During the 12-year follow-up, patients with RAO had a shorter time to death (49.95 vs. 15.74 months; p = 0.043), a higher all-cause mortality rate (log-rank p = 0.026, and a higher rate of the composite endpoint, including ischemic stroke, myocardial infarction, and all-cause mortality (log-rank p = 0.024), as compared with controls. Patients with RAO younger than 75 years showed a higher risk of cerebral ischemic stroke (log-rank p = 0.008), all-cause mortality (log-rank p = 0.023), and the composite endpoint (log-rank p = 0.001) than controls. However, these associations were not demonstrated for patients aged 75 years or older. Our study confirms that patients with RAO have a higher risk of all-cause mortality than those without RAO. Moreover, patients with RAO who are younger than 75 years are significantly more likely to experience ischemic stroke, death, or the composite endpoint after an occlusion event, as compared with individuals without RAO. Full article

Purpose: Retinal artery occlusion (RAO) is associated with an increased risk of cardiovascular events such as ischemic stroke and myocardial infarction, but whether different RAO subtypes such as central retinal artery occlusion (CRAO) or branch retinal artery occlusion (BRAO) carry similar risk of these events is unclear. Our aim was to determine whether the risk of cardiovascular events differs between CRAO and BRAO. Methods: This single-center, retrospective study included 131 patients hospitalized in our clinic in 2010–2020 with CRAO or BRAO confirmed by ophthalmic examination. Data on demographics, previous ischemic stroke and myocardial infarction, comorbidities, the results of echocardiographic and ultrasound carotid artery examinations and laboratory tests were assessed. Data on ischemic stroke, myocardial infarction, and all-cause mortality occurring after RAO were obtained from the Polish National Health Service, which collects data on all publicly funded hospitalizations. Using these data, Kaplan-Meier analyses and Cox proportional hazard regression were performed. Results: Ischemic stroke occurred in 9.9% of patients after RAO: 10.6% in the CRAO group and 8.1% in the BRAO group (p = 0.662). Myocardial infarction occurred in 2.3% of patients after RAO: 2.1% in the CRAO group and 2.7% in the BRAO group (p = 0.843). All-cause mortality occurred in 22.9% of patients after RAO: 25.5% in the CRAO group and 16.2% in the BRAO group (p = 0.253). The composite endpoint of ischemic stroke, myocardial infarction, and all-cause mortality after RAO occurred in 28.2% of patients: 30.9% in the CRAO group and 21.6% in the BRAO group (p = 0.338). There was no difference between CRAO and BRAO in median time to ischemic stroke (32 vs. 76.4 months; p = 0.352), all-cause mortality (35.9 vs. 36.3 months; p = 0.876) or composite endpoint (37.5 vs. 41.5 months; p = 0.912) after RAO. The Kaplan-Meier analysis showed no differences between CRAO and BRAO in ischemic stroke, myocardial infarction, all-cause mortality, or the composite endpoint; similar results were obtained in analyses of patients with and without cardiovascular events before RAO. Conclusions: The prognosis for ischemic stroke, myocardial infarction, and all-cause mortality is similar in patients with CRAO and BRAO. Ischemic strokes occur with a similar frequency before and after RAO. Myocardial infarctions are observed significantly more frequently before an episode of RAO than after. The results of our study indicate that both CRAO and BRAO require expanded diagnostics to assess the risk of recurrent cardiovascular events, especially ischemic strokes, to implement appropriate prophylaxis and reduce mortality. Full article

Nutritional supplementation with antioxidants and vitamins is widely recommended in the treatment of vascular disorders affecting the retina, although there is insufficient evidence on its effectiveness. The vitamin-like compound coenzyme Q10 (CoQ10) is a nutritional supplement of current interest to treat neurodegenerative diseases. Here, we report a retrospective clinical case series study of 48 patients diagnosed with retinal vascular diseases, including non-arteritic ischemic optic neuropathy (NAION), retinal artery occlusion (RAO), and homonymous hemianopia or quadrantanopia following stroke, treated with oral supplementation with CoQ10 (100 mg per day) and vitamins. Patient follow-up was performed using the Humphrey field analyzer and 30-2 testing algorithm to determine the visual field index (VFI) and progression rates. All treated patients showed positive VFI progression rates per year: +11.5 ± 15% for NAION patients (n = 18), +22 ± 17% for RAO patients (n = 7), +9.3 ± 10.5% for hemianopia/quadrantanopia patients (n = 10), and +11 ± 21% for patients with other conditions (n = 13). The interruption of CoQ10 supplementation in one patient resulted in a pronounced decrease of the VFI, which was partially recovered when treatment was restored. This study supports the role of CoQ10 as a nutritional therapeutic agent for vascular diseases affecting the retina. Owing to decreased VFI after interruption of CoQ10, its beneficial effects may be reversible. Full article

Retinal artery occlusion (RAO), retinal vein occlusion (RVO), diabetic retinopathy (DR) and age-related macular degeneration (AMD) are frequent ocular diseases with potentially sight-threatening outcomes. In the present review we discuss major findings of proteomic studies of RAO, RVO, DR and AMD, including an overview of ocular proteome changes associated with anti-vascular endothelial growth factor (VEGF) treatments. Despite the severe outcomes of RAO, the proteome of the disease remains largely unstudied. There is also limited knowledge about the proteome of RVO, but proteomic studies suggest that RVO is associated with remodeling of the extracellular matrix and adhesion processes. Proteomic studies of DR have resulted in the identification of potential therapeutic targets such as carbonic anhydrase-I. Proliferative diabetic retinopathy is the most intensively studied stage of DR. Proteomic studies have established VEGF, pigment epithelium-derived factor (PEDF) and complement components as key factors associated with AMD. The aim of this review is to highlight the major milestones in proteomics in RAO, RVO, DR and AMD. Through large-scale protein analyses, proteomics is bringing new important insights into these complex pathological conditions. Full article