Retinal vein occlusion: an approach to diagnosis, systemic risk factors and management

Insights into modifiable risk factors of retinal vascular occlusion: A Mendelian randomization study

Understanding the etiological risk factors for retinal vascular occlusion (RVO) is critical for prevention and treatment. While the effects of cardiovascular events, hypertension, glaucoma, obesity and glycemic risk factors on RVO are still controversial. This study employed two-sample Mendelian randomization (MR) analysis to investigate these causal risk factors. Single-nucleotide polymorphisms (SNPs) were used as instrumental variables (IVs). Genetic instruments for hypertension, glaucoma, obesity, cardiovascular events and glycemic risk factors were obtained from published genome-wide association studies (GWASs). Summary-level data for RVO and hypertension were obtained from the FinnGen consortium. MR analysis primarily utilized the inverse variance weighted (IVW) method, with MR-Egger and weighted median as supplementary approaches. Multivariable MR (MVMR) adjusting for hypertension or glaucoma of RVO were conducted. Heterogeneity was assessed using Cochrane's Q test and I2, while MR-Egger intercept and MR-PRESSO tested horizontal pleiotropy. All MR analyses were performed within R software (4.1.3) using the R packages "TwoSampleMR" and "MR-PRESSO." Genetic instruments for hypertension and glaucoma were significantly associated with RVO risk. A one-standard deviation (SD) increase in hypertension was associated with a higher risk of RVO [OR = 1.577, 95% CI = (1.342, 1.854), P < .001], while a one-SD increase in the log odds of genetically predicted glaucoma was associated with a higher risk of RVO [OR = 1.24, 95% CI = (1.115, 1.379), P < .001]. Meanwhile, hypertension and glaucoma were still significant in multivariable MR. There was not sufficient evidence to suggest cardiovascular events and obesity were associated with RVO risk. This MR study provided genetic evidence supporting that hypertension and glaucoma were causally associated with the risk of RVO. It may help guide clinical decisions in the management of RVO patients with hypertension and glaucoma.

Risk factors of retinal vein occlusion in East Asia: a meta-analysis

Objective

With the intention of developing a more targeted control strategy for retinal vein occlusion (RVO) in East Asian populations, a meta-analysis was conducted to evaluate the risk factors associated with RVO in this region.

Methods

PubMed, Web of Science, Cochrane Library, CNKI, Wanfang and VIP databases were searched for studies that reported risk factors of RVO in East Asia, published from the establishment of the database to May 2024. To further filter the articles, Newcastle-Ottawa Scale (NOS) evaluation method was utilized to assess the quality of selected articles. After valid data were extracted, Meta-analysis was performed by Review Manager software.

Results

A total of 21 literatures were included, including 27561 cases in the RVO group (Case group) and 514578 cases in the non-retinal vein occlusion (NRVO) group (Control group). Results of meta-analysis showed that chronic kidney disease [odds ratio (OR)=4.14, 95% confidence interval (CI): (1.86%, 9.24%)], hypertension [OR=4.11, 95% CI: (3.09%, 5.48%)], hyperlipidemia [OR=3.45, 95%CI: (2.32%, 5.12%)], diabetes mellitus [OR=3.00, 95%CI: (1.88%, 4.80%)], homocysteine [OR=0.87, 95%CI: (0.59%, 1.15%)], have statistically significant differences between the RVO group and the NRVO group(P<0.05).

Conclusion

The occurrence of RVO is closely related to its risk factors, such as chronic kidney disease, hypertension, hyperlipidemia, diabetes mellitus and high homocysteine. In the process of diagnosis and treatment of RVO, doctors should focus on the above risk factors to prevent the occurrence of the disease.

The effect of coagulation traits on the risk of retinal vein occlusion: a mendelian randomization study

Retinal vein occlusion (RVO) is the leading cause of vision loss due to an obstruction in the retinal venous system. While RVO is often linked to thrombotic tendencies and coagulation abnormalities, the exact role of coagulation traits in its development is not fully understood. This study aims to investigate the potential causal relationship between coagulation traits and the risk of RVO by analyzing publicly available genome-wide association study (GWAS) summary statistics. A two-sample Mendelian randomization (MR) analysis framework was employed to investigate the causal relationship between coagulation traits and the risk of RVO. Stringent quality control measures were applied to select appropriate instrumental variables strongly linked to exposure, such as coagulation factor III (FIII), coagulation factor V (FV), coagulation factor VIII (FVIII), coagulation factor XI (FXI), coagulation factor VII (FVII) and coagulation factor X (FX), as well as plasmin, platelet count, platelet crit (PCT), mean platelet volume (MPV), and platelet distribution width (PDW). The study utilized the FinnGen project RVO GWAS summary statistics cohort, consisting of 372 RVO cases and 182,573 controls. The analysis focused on 11 coagulation traits. The research suggests that genetically predicted plasma levels of FIII, FVII, MPV, and PCT may be potentially causative for reducing the risk of RVO, and that levels of FVIII may be potentially causative for increasing the risk of RVO. Our MR analysis, utilizing GWAS data from a comprehensive population-based study, revealed a causal association between plasma levels of FIII, FVII, FVIII, MPV, and PCT with the risk of RVO.

Long term efficacy and safety profile of dexamethasone intravitreal implant in retinal vein occlusions: a systematic review

Background/objective

Retinal vein occlusion (RVO) is a common, sight-threatening vascular disorder affecting individuals of all ages, with incidence increasing with age. Due to its complex, multifactorial nature, treating RVO remains a clinical challenge. Currently, treatment strategies include laser photocoagulation (especially for branch RVO), anti-VEGF therapies, and intravitreal corticosteroids. This systematic review (without meta-analysis) aimed to update the evidence on the efficacy and safety of the sustained-release intravitreal dexamethasone implant (DEX-i) in managing macular edema (ME) secondary to central and branch RVO.

Methods

A systematic review was conducted to assess current literature on DEX-i for ME secondary to RVO. Relevant studies were analyzed for outcomes related to visual acuity, retinal thickness, and the safety profile of DEX-i in RVO treatment.

Results

Evidence indicates that DEX-i substantially improves best-corrected visual acuity (BCVA) and reduces central retinal thickness (CRT) in ME associated with both branch and central RVO, demonstrating rapid and sustained effects. Common adverse events associated with DEX-i included manageable complications, such as medically controlled intraocular pressure elevation and progression of cataracts.

Conclusion

DEX-i offers effective and sustained improvements in both visual and anatomical outcomes for patients with ME secondary to RVO. Individualized treatment selection is essential to optimize patient outcomes. Future directions include identifying predictive biomarkers and adopting patient-centered approaches based on individual clinical characteristics, which may enhance treatment success in RVO.

Molecular and Cellular Mechanisms Involved in the Pathophysiology of Retinal Vascular Disease-Interplay Between Inflammation and Oxidative Stress

Retinal vascular diseases encompass several retinal disorders, including diabetic retinopathy, retinopathy of prematurity, age-related macular degeneration, and retinal vascular occlusion; these disorders are classified as similar groups of disorders due to impaired retinal vascularization. The aim of this review is to address the main signaling pathways involved in the pathogenesis of retinal vascular diseases and to identify crucial molecules and the importance of their interactions. Vascular endothelial growth factor (VEGF) is recognized as a crucial and central molecule in abnormal neovascularization and a key phenomenon in retinal vascular occlusion; thus, anti-VEGF therapy is now the most successful form of treatment for these disorders. Interaction between angiopoietin 2 and the Tie2 receptor results in aberrant Tie2 signaling, resulting in loss of pericytes, neovascularization, and inflammation. Notch signaling and hypoxia-inducible factors in ischemic conditions induce pathological neovascularization and disruption of the blood-retina barrier. An increase in the pro-inflammatory cytokines-TNF-α, IL-1β, and IL-6-and activation of microglia create a persistent inflammatory milieu that promotes breakage of the blood-retinal barrier and neovascularization. Toll-like receptor signaling and nuclear factor-kappa B are important factors in the dysregulation of the immune response in retinal vascular diseases. Increased production of reactive oxygen species and oxidative damage follow inflammation and together create a vicious cycle because each factor amplifies the other. Understanding the complex interplay among various signaling pathways, signaling cascades, and molecules enables the development of new and more successful therapeutic options.

Case reports: Intraoperative migratory retinal venous thrombus in proliferative diabetic retinopathy

Purpose

This study aimed to study the characteristics, possible causes, and clinical implications of intraoperative migratory retinal venous thrombus in proliferative diabetic retinopathy (PDR).

Cases

Two middle-aged Chinese patients with diabetes mellitus presented with blurred vision and were diagnosed with PDR and tractional retinal detachment (TRD). An interesting phenomenon was observed during pars plana vitrectomy in both patients. Movement of tiny white thrombi and interruption of blood flow were observed in a branch of the central retinal vein when the vein was pulled at the time of fibrovascular membrane delamination and disappeared with the elimination of retinal traction after finishing the process of delamination. Laboratory studies revealed abnormal erythrocyte sedimentation rate, fibrinogen, D-dimer, international normalized ratio, and IgA anti-β2-glycoprotein I in one patient and elevated fibrinogen and IgA anticardiolipin in the other. Follow-up examinations at 1 week, 1, 3, and 6 months postoperatively showed good prognosis. Fluorescein fundus angiography at 1 month postoperatively showed neither embolus sign nor prolonged venous filling time in both patients.

Discussion

Local blood stasis of the retinal vein persistently dragged by the fibrovascular membrane may result in thrombogenesis, and traction of the retina during the delamination process may lead to the movement of thrombi. On the other hand, endothelial injury and disordered local blood stasis during delamination may also activate the biological coagulation process and instant thrombus formation. As well, antiphospholipid antibodies may also be a risk factor of ocular thrombogenesis.

Conclusion

This study provides the first videos recording migratory thrombus in terminal vessels, which indicates that fibrovascular membrane in PDR can lead to thrombogenesis due to dragging and hemostasis of the involved retinal vein. PDR patients with fibrovascular membranes may benefit from early relief of vascular traction through fibrovascular membrane delamination.

Generating Synthesized Fluorescein Angiography Images From Color Fundus Images by Generative Adversarial Networks for Macular Edema Assessment

Purpose

To assess the feasibility of generating synthetic fluorescein angiography (FA) images from color fundus (CF) images using pixel-to-pixel generative adversarial network (pix2pixGANs) for clinical applications. Research questions addressed image realism to retinal specialists and utility for assessing macular edema (ME) in Retinal Vein Occlusion (RVO) eyes.

Methods

We used a registration-guided pix2pixGANs method trained on the CF-FA dataset from Kham Eye Centre, Kandze Prefecture People's Hospital. A visual Turing test confirmed the realism of synthetic images without novel artifacts. We then assessed the synthetic FA images for assessing ME. Finally, we quantitatively evaluated the synthetic images using Fréchet Inception distance (FID) and structural similarity measures (SSIM).

Results

The raw development dataset had 881 image pairs from 349 subjects. Our approach is capable of generating realistic FA images because small vessels are clearly visible and sharp within one optic disc diameter around the macula. Two retinal specialists agreed that more than 85% of synthetic FA images have good or excellent image quality. For ME detection, accuracy was similar for real and synthetic images. FID demonstrated a 38.9% improvement over the previous state-of-the-art (SOTA), and SSIM reached 0.78 compared to the previous SOTA's 0.67.

Conclusions

We developed a pix2pixGANs model translating FA images from label-free CF images, yielding reliable synthetic FA images. This suggests potential for noninvasive evaluation of ME in RVO eyes using pix2pix GANs techniques.

Translational Relevance

Pix2pixGANs techniques have the potential to assist in the noninvasive clinical assessment of ME in RVO eyes.

Soul: An OCTA dataset based on Human Machine Collaborative Annotation Framework

Branch retinal vein occlusion (BRVO) is the most prevalent retinal vascular disease that constitutes a threat to vision due to increased venous pressure caused by venous effluent in the space, leading to impaired visual function. Optical Coherence Tomography Angiography (OCTA) is an innovative non-invasive technique that offers high-resolution three-dimensional structures of retinal blood vessels. Most publicly available datasets are collected from single visits with different patients, encompassing various eye diseases for distinct tasks and areas. Moreover, due to the intricate nature of eye structure, professional labeling not only relies on the expertise of doctors but also demands considerable time and effort. Therefore, we have developed a BRVO-focused dataset named Soul (Source of ocular vascular) and propose a human machine collaborative annotation framework (HMCAF) using scrambled retinal blood vessels data. Soul is categorized into 6 subsets based on injection frequency and follow-up duration. The dataset comprises original images, corresponding blood vessel labels, and clinical text information sheets which can be effectively utilized when combined with machine learning.

Measuring patient activation: the utility of the Patient Activation Measure administered in an interview setting

BACKGROUND

Patient activation is an emerging field in healthcare research concerning knowledge, skills, and confidence of patients in managing their health. This is particularly important for patients with chronic diseases, who often require more complex care management and self-care skills. However, due to temporary or longer-lasting visual impairments, certain patient groups cannot answer a questionnaire independently. The main objective is to investigate the psychometric properties of the German Patient Activation Measure® (PAM) survey in an everyday clinical setting where it has to be read aloud.

METHODS

Outpatients with macular edema participated in this questionnaire-based cross-sectional study. The study assessed patient activation by the PAM® survey, self-rated health, self-efficacy, quality of life, and general mood. Interviewers read questionnaires aloud to patients. Psychometric properties of the PAM® survey were investigated by item response theory (IRT), Cronbach's α and trait-trait correlations.

RESULTS

The analysis included N = 554 patients. Median age was 69 (IQR 62.0-76.0) years and mean overall activation score 74.1 (SD 13.7). All items showed ceiling effects. Empirical reliability from the IRT model and Cronbach's α were 0.75. The PAM® survey showed a Spearman correlation of 0.54 with self-efficacy, 0.51 with quality of life and 0.34 with general mood.

CONCLUSION

The read-aloud PAM® survey has been shown to provide to adequate measurement precision and convergent validity to be used as a screening tool in an everyday clinical setting. Objective assessment in an interview setting with the PAM® survey is possible. PAM® items are good in distinguishing lower to middle activated patients, but not patients with high activation. Further, issues with structural validity need more investigation.

Hypertension, hyperlipidaemia and thrombophilia as the most common risk factors for retinal vein occlusion in patients under 50 years

BACKGROUND AND AIMS

Cardiovascular (CV) diseases are the most common risk factors (RFs) for retinal vein occlusion (RVO) development in general. The aim of this study was to identify the most frequent causes of RVO in patients under 50.

METHODS

We retrospectively evaluated a group of patients with RVO under 50 years. The parameters of interest included age and sex, RVO type, presence of arterial hypertension (HT), hyperlipidaemia (HLD), diabetes mellitus (DM), congenital thrombophilic disorder (TD), obstructive sleep apnoea syndrome (OSAS), thyroid eye disease (TED), use of hormone contraception (HC) or hormone replacement therapy (HRT), glaucoma and other potential RFs. Patients with central RVO (CRVO), hemi-central RVO (HRVO), branch RVO (BRVO), impending CRVO and combined arterial-venous (AV) occlusion were included.

RESULTS

The group consisted of 110 eyes of 103 patients. CV disease was the most common systemic abnormality. 55.3% patients had HT, 17.5% had HLD. TD was the third most frequent RF (12.6%). The cohort also included patients with DM (6.8%), glaucoma (6.8%) and women using HC/HRT (26.2% of female patients). There were isolated cases of RVO due to retinal vasculitis, intense exercise, antiphospholipid syndrome and COVID-19 pneumonia. None of the patients had OSAS, TED or a haemato-oncological disease. The etiology remained unexplained in 20.4% patients. No difference was observed in RF occurrence between patients with CRVO and HRVO and those with BRVO.

CONCLUSION

The most common systemic abnormality in our cohort was CV disease, especially HT and HLD. The risk factors for central, hemi-central and branch RVOs were similar.

Long-Term Outcomes in Early versus Limited Response to Anti-VEGF Treatment for Retinal Vein Occlusion

OBJECTIVE

Macular edema secondary to retinal vein occlusion (RVO) is a sight-threatening condition. Previous studies showed that early responders (ERs) who respond well to anti-VEGF injections within 3 months of treatment have better outcomes, as measured by best visual acuity (BVA) and central subfield thickness (CST) at 12 months postinjection initiation compared with limited early responders (LERs). This study analyzed whether ER eyes continue to respond better than LER eyes over longer periods. This study also aimed to identify baseline comorbidities associated with response status.

DESIGN

Retrospective cohort study.

PARTICIPANTS

Patients aged > 18 years with RVO-related macular edema treated with anti-VEGF injections.

METHODS

Patients were categorized as ERs or LERs. Limited early responder eyes were defined as having CST reduction < 10%, BVA gain < 5 ETDRS letters, or both at 3 months after anti-VEGF initiation. Best visual acuity and CST changes over the 24- and 36-month period after the first anti-VEGF treatment were compared between ERs and LERs. Patient characteristics and systemic comorbidities were identified by chart review. Statistical analysis involved the Levene test, Welch t test, and Welch analysis of variance.

MAIN OUTCOME MEASURES

Best visual acuity and CST changes over the initial 24-month and 36-month periods after treatment.

RESULTS

The 24-month cohort included 68 ERs and 39 LERs, and the 36-month cohort included 58 ERs and 33 LERs. At the 24-month time point, there were significant differences in BVA and CST gains between ERs (+19.8 letters, -221.2 um) and LERs (-2.4 letters, -90.1 um; P < 0.001, P < 0.01). Similarly, at 36 months, there were significant differences in BVA and CST gains between ERs (+17.7 letters, -229.3 um) and LERs (+1.3 letters, -128 um; P < 0.001, P < 0.05). After controlling for differences in baseline BVA and CST, only the 24-month change in BVA remained significant (P < 0.001). There were no significant associations between response status and cardiopulmonary, endocrine, and oncologic comorbidities.

CONCLUSIONS

Early responder eyes with branched retinal vein occlusion (BRVO) and central retinal vein occlusion (CRVO) have better functional responses to anti-VEGF injections at 24 months compared with LER eyes, even after controlling for baseline differences. Early identification of eyes as ERs or LERs in BRVO and CRVO may predict long-term functional prognoses.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Maximum carotid intima-media thickness and NT-pro BNP in association with retinal vein occlusion

The purpose is to clarify the relationship between patients with retinal vein occlusion (RVO), maximal intima-media complex thickness (Max IMT), and N-terminal pro-brain natriuretic peptide (NT-proBNP), which is useful in assessing atherosclerosis. This was a retrospective observation, single center study. The patients were 86 RVO patients (male: female = 43:43, mean age 63.3 years), 25 with central retinal vein occlusion (CRVO) and 61 with branch retinal vein occlusion (BRVO), classified as ≧50 years old and <50 years old, Max IMT≧1.1 and less, NT-pro BNP≧55 and less. Results showed that Max IMT ≧1.1 was significantly more common in both the CRVO and BRVO groups at ≧50 years, and NT-pro BNP ≧55 was significantly more common in the CRVO group. Max IMT≧1.1 was seen in 80% of the BRVO group and in 85% of patients aged ≧50 years. Sixty-eight percent of patients in the CRVO group had Max IMT≧1.1, but none of those < 50 years had Max IMT≧1.1. Forty-eight percent of RVO patients had NT-pro BNP≧55, and significantly more patients had Max IMT≧1.1 than those who did not have NT-pro BNP more than 55 (p = 0.02). Multiple regression analysis with Max IMT as the dependent variable showed that age and NT-pro BNP were significantly associated with RVO (p = 0.015, 0.022). RVO patients were more likely to have a Max IMT≧1.1, which was associated with atherosclerosis. Max IMT and NT-pro BNP were also associated with RVO patients, so NT-pro BNP may be a marker of RVO.

Risk of retinopathy in women with pregnancy-induced hypertension: a nationwide population-based cohort study of 9-year follow-up after delivery

BACKGROUND

The retina is potentially associated with several physiological, hormonal, and metabolic changes during pregnancy. The few available epidemiologic studies of ocular changes in pregnancy have mainly concerned retinopathies. Pregnancy-induced hypertension, which leads to ocular manifestations including blurred vision, photopsia, scotoma, and diplopia, might induce reactive changes in the retinal vessels. Although several studies have suggested the existence of pregnancy-induced hypertension-related retinal ocular disease, there are few large cohort studies on this topic.

OBJECTIVE

This study aimed to investigate the risk of major retinal diseases including central serous chorioretinopathy, diabetic retinopathy, retinal vein occlusion, retinal artery occlusion, and hypertensive retinopathy in the long-term postpartum stage according to the presence of previous pregnancy-induced hypertension in a large cohort based on the Korean National Health Insurance Database.

STUDY DESIGN

On the basis of Korean health data, 909,520 patients who delivered from 2012 to 2013 were analyzed. Among them, patients who had previous ocular diseases or hypertension and multiple births were excluded. Finally, 858,057 mothers were assessed for central serous chorioretinopathy (ICD-10: H35.70), diabetic retinopathy (ICD-10: H36.0, E10.31, E10.32, E11.31, E11.32, E12.31, E13.31, E13.32, E14.31, E14.32), retinal vein occlusion (ICD-10: H34.8), retinal artery occlusion (ICD-10: H34.2), and hypertensive retinopathy (ICD-10: H35.02) for 9 years after delivery. Enrolled patients were divided into 2 groups: 10,808 patients with and 847,249 without pregnancy-induced hypertension. The primary outcomes were the incidence of central serous chorioretinopathy, diabetic retinopathy, retinal vein occlusion, retinal artery occlusion, and hypertensive retinopathy 9 years after delivery. Clinical variables were age, parity, cesarean delivery, gestational diabetes mellitus, and postpartum hemorrhage. In addition, pregestational diabetes mellitus, kidney diseases, cerebrovascular diseases, and cardiovascular diseases were adjusted.

RESULTS

Postpartum retinal disease during the 9 years after delivery and total retinal diseases showed higher rates in patients with pregnancy-induced hypertension. In detail, the rates of central serous chorioretinopathy (0.3% vs 0.1%), diabetic retinopathy (1.79% vs 0.5%), retinal vein occlusion (0.19% vs 0.1%), and hypertensive retinopathy (0.62% vs 0.05%) were higher than those found in patients without pregnancy-induced hypertension. After adjusting for confounding factors, pregnancy-induced hypertension was associated with development of postpartum retinopathy, with a >2-fold increase (hazard ratio, 2.845; 95% confidence interval, 2.54-3.188). Furthermore, pregnancy-induced hypertension affected the development of central serous chorioretinopathy (hazard ratio, 3.681; 95% confidence interval, 2.667-5.082), diabetic retinopathy (hazard ratio, 2.326; 95% confidence interval, 2.013-2.688), retinal vein occlusion (hazard ratio, 2.241; 95% confidence interval, 1.491-3.368), and hypertensive retinopathy (hazard ratio, 11.392; 95% confidence interval, 8.771-14.796) after delivery.

CONCLUSION

A history of pregnancy-induced hypertension increases the risk of central serous chorioretinopathy, diabetic retinopathy, retinal vein occlusion, and hypertensive retinopathy according to 9-year long-term ophthalmologic follow-up.

The risk of retinal vein occlusion among patients with neovascular age related macular degeneration: a large-scale cohort study

PURPOSE

To examine the risk for retinal-vein-occlusion (RVO) in patients with neovascular age-related-macular-degeneration (AMD) as compared to age- and sex-matched controls.

METHOD

This is a population-based, cohort study. The study encompassed 24,578 consecutive patients with neovascular AMD and 66,129 control subjects. Multivariate cox regression analysis was utilized to detect the risk of RVO among patients with neovascular AMD. Predictors of RVO in patients with neovascular AMD were identified using multivariate logistic regression analysis. Mortality of patients was assessed using Kaplan-Meier method.

RESULTS

The incidence rate of RVO was estimated at 1.25 (95% CI, 1.06-1.45) per 1000 person-years among patients with neovascular AMD and 0.25 (95% CI, 0.20-0.31) per 1000 person-years among controls. Patients with neovascular AMD were associated with an increased risk of RVO (adjusted HR, 4.35; 95% CI, 3.34-5.66; P < 0.001). Among patients with neovascular AMD, older age (≥79.0 years) was associated with a decreased risk of RVO (adjusted OR, 0.50; 95% CI, 0.37-0.70; P < 0.001), whilst a history of glaucoma increased the likelihood of RVO (adjusted OR, 2.66; 95% CI, 1.94-3.65; P < 0.001). Patients with neovascular AMD and comorbid RVO had a comparable risk of all-cause mortality relative to other patients with neovascular AMD (HR, 0.90; 95% CI, 0.67-1.22; P = 0.500) CONCLUSIONS: An increased risk of RVO was found among patients with neovascular AMD. Younger age and glaucoma predicted the development of RVO in patients with neovascular AMD. Awareness of this comorbidity is of benefit for clinicians as patients with neovascular AMD might be carefully examined for RVO signs and complications.

Postponed care due to COVID-19 lockdown impact on visual acuity of retinal vein occlusion patients: a large cohort

PURPOSE

To evaluate the impact of postponed care attributed to coronavirus disease (COVID-19) pandemic lockdowns on visual acuity and the number of anti-VEGF injections in patients with retinal vein occlusion (RVO).

METHODS

A multicenter, retrospective study of consecutive RVO patients previously treated with anti-VEGF injections, which compared data from pre- (2019) and during (2020) COVID-19 lockdown period.

RESULTS

A total of 814 RVO patients with a mean age of 72.8 years met the inclusion criteria. Of them, 439 patients were assessed in 2019 and 375 in 2020. There was no significant difference between the COVID-19 and pre-COVID-19 period in terms of baseline and final BCVA (p = 0.7 and 0.9 respectively), but there was a significantly reduced mean number of anti-VEGF injections during the COVID-19 period (5.0 and. 5.9 respectively, p < 0.01), with a constant lower ratio of injections per patient. A noticeable decline was found during March-May (p < 0.01) in 2020. Baseline BCVA (0.69, p < 0.01) and the number of injections (- 0.01, p = 0.01) were predictors of final BCVA.

CONCLUSIONS

In a large cohort of RVO patients, during 2020 lockdowns imposed due to the COVID-19 pandemic, a significant reduction in the annual number of anti-VEGF injections was noted. The postponed care did not result in a significant impact on the final BCVA. Baseline BCVA and the number of annual injections serve as predictors for final BCVA in RVO patients.

Differential expression of aqueous humor microRNAs in central retinal vein occlusion and its association with matrix metalloproteinases: a pilot study

The aim of this study is to investigate the differential expression of microRNAs (miRNAs) in the aqueous humor (AH) of patients with central retinal vein occlusion (CRVO), and their association with AH matrix metalloproteinase (MMP) activity. Eighteen subjects, including 10 treatment naïve patients with CRVO and 8 control subjects, scheduled for intravitreal injection and cataract surgery, respectively, were included. AH samples were collected at the beginning of the procedure. A microarray composed of 84 miRNAs was performed to identify differentially expressed miRNAs in CRVO AH, which were further analyzed using bioinformatic tools to identify directly related cytokines/proteins. Eight miRNAs (hsa-mir-16-5p, hsa-mir-142-3p, hsa-mir-19a-3p, hsa-mir-144-3p, hsa-mir-195-5p, hsa-mir-17-5p, hsa-mir-93-5p, and hsa-mir-20a-5p) were significantly downregulated in the CRVO group. Bioinformatic analysis revealed a direct relationship among downregulated miRNAs, CRVO, and the following proteins: MMP-2, MMP-9, tumor necrosis factor, transforming growth factor beta-1, caspase-3, interleukin-6, interferon gamma, and interleukin-1-beta. Activities of MMP-2 and -9 in AH were detected using gelatin zymography, showing significant increase in the CRVO group compared to the control group (p < 0.01). This pilot study first revealed that MMP-2 and -9 were directly related to downregulated miRNAs and showed significant increase in activity in AH of patients with CRVO. Therefore, the relevant miRNAs and MMPs in AH could serve as potential biomarkers or therapeutic targets for CRVO.

A review of risk factors for retinal vein occlusions

INTRODUCTION

Risk factors for retinal vein occlusion have been extensively studied, with varying population sizes. Smaller populations result in less certain measures of associations. The present review included studies with a relevant population size to identify clinically relevant risk factors for retinal vein occlusion. Understanding the risk factors of retinal vein occlusion is important for the management of these patients.

AREAS COVERED

A comprehensive literature review was conducted through a systematic literature search in PubMed and Embase. Additional studies were selected from cross references in the assessed studies. Weighted effect measures were calculated for all included risk factors.Risk factors associated with retinal vein occlusion included cardiovascular diseases, eye diseases, systemic diseases, medical interventions, and sociodemographic factors.

EXPERT OPINION

This review provided an extensive overview of a wide variety of risk factors increasing the risk of developing retinal vein occlusion. The severity of the identified risk factors indicated that these patients have been in contact with the health care system before their retinal vein occlusion event. Therefore, the clinical course for patients with retinal vein occlusion may benefit from a multidisciplinary collaboration between ophthalmologists and especially cardiologists.

AutoMorph: Automated Retinal Vascular Morphology Quantification Via a Deep Learning Pipeline

Purpose

To externally validate a deep learning pipeline (AutoMorph) for automated analysis of retinal vascular morphology on fundus photographs. AutoMorph has been made publicly available, facilitating widespread research in ophthalmic and systemic diseases.

Methods

AutoMorph consists of four functional modules: image preprocessing, image quality grading, anatomical segmentation (including binary vessel, artery/vein, and optic disc/cup segmentation), and vascular morphology feature measurement. Image quality grading and anatomical segmentation use the most recent deep learning techniques. We employ a model ensemble strategy to achieve robust results and analyze the prediction confidence to rectify false gradable cases in image quality grading. We externally validate the performance of each module on several independent publicly available datasets.

Results

The EfficientNet-b4 architecture used in the image grading module achieves performance comparable to that of the state of the art for EyePACS-Q, with an F1-score of 0.86. The confidence analysis reduces the number of images incorrectly assessed as gradable by 76%. Binary vessel segmentation achieves an F1-score of 0.73 on AV-WIDE and 0.78 on DR HAGIS. Artery/vein scores are 0.66 on IOSTAR-AV, and disc segmentation achieves 0.94 in IDRID. Vascular morphology features measured from the AutoMorph segmentation map and expert annotation show good to excellent agreement.

Conclusions

AutoMorph modules perform well even when external validation data show domain differences from training data (e.g., with different imaging devices). This fully automated pipeline can thus allow detailed, efficient, and comprehensive analysis of retinal vascular morphology on color fundus photographs.

Translational Relevance

By making AutoMorph publicly available and open source, we hope to facilitate ophthalmic and systemic disease research, particularly in the emerging field of oculomics.

Anti-Vascular Endothelial Growth Factor Treatment for Macular Edema in Eyes with Branch Retinal Vein Occlusion with vs Without Glaucoma – Does Glaucoma Affect Visual Outcome in Eyes with BRVO-ME After antiVEGF Injections?

Purpose

To compare the therapeutic effects of anti-vascular endothelial growth factor (anti-VEGF) agents in eyes with macular edema associated with branch retinal vein occlusion (BRVO-ME) with glaucoma to those without glaucoma.

Patients and Methods

This retrospective study was conducted using the medical records of Mie University Hospital from 2013 to 2017. Patients were recruited if they had received anti-VEGF agents for BRVO-ME treatment and included 30 patients (30 eyes) without glaucoma (G[-] group) and 27 patients (27 eyes) with glaucoma (G[+] group). The central retinal thickness (CRT) and best-corrected visual acuity (BCVA) at 3 months after a single injection of anti-VEGF agents were compared between the two groups.

Results

Before treatment, the mean±standard deviation of the CRT was 514.2±117.3 μm for the G[-] group, which was not significantly different from that for the G[+] group (533.4±171.4 μm). The CRT in the G[-] and G[+] groups significantly reduced to 321.1±114.6 μm and 347.8±134.7 μm, respectively, at 1 month after the injection and to 360.4±159.5 μm and 352.4±151.9 μm, respectively, at 3 months after the injection (P<0.01 for each group). The difference in the degree of CRT reduction between the two groups was not significant. Before treatment, the BCVA was 0.42±0.32 logMAR units in the G[-] group and 0.57±0.33 logMAR units in the G[+] group, showing no significant difference. The BCVA in the G[-] and G[+] groups improved significantly to 0.27±0.26 logMAR units and 0.34±0.42 logMAR units, respectively, at 1 month, and to 0.18±0.20 logMAR units and 0.39±0.34 logMAR units, respectively, at 3 months (P<0.01). The BCVA in the G[-] group was significantly better than that in the G[+] group at 3 months (P=0.02).

Conclusion

The therapeutic response of anti-VEGF agents for BRVO-ME is affected by the presence of glaucoma.

Case Report: A Case of Cystoid Macular Edema in Retinitis Pigmentosa With Central Retinal Vein Occlusion

Significance

Cystoid macular edema (CME) is a common complication of retinitis pigmentosa (RP). However, CME in RP with central retinal vein occlusion (CRVO) is rare. Prompt administration of anti-vascular endothelial growth factor (anti-VEGF) medication can achieve a satisfactory prognosis.

Purpose

This report describes a case of using anti-VEGF medication to treat CME secondary to RP with impending or mild CRVO.

Case Report

A 26-year-old female presented for blurred vision in both eyes. Best-corrected visual acuity (BCVA) was 20/50 in the right eye and finger-counting in the left eye. According to ophthalmic examinations, CME secondary to RP in the right eye and CME secondary to RP with impending or mild CRVO in her left eye can be diagnosed. Central macular thickness (CMT) was 554 μ m in the right eye and 831 μm in the left eye. Only the left eye was treated with a single intravitreal injection of anti-VEGF medication. One month later, BCVA increased to 20/200 and CMT decreased to 162 μm in the left eye. Interestingly, BCVA in the right eye also had an improvement (20/40) and intraretinal fluid decreased significantly. However, 3 months after injection, these improvements of both eyes were not maintained.

Conclusion

This is the second case of RP with CRVO. Intravitreal injection of anti-VEGF medication for addressing CME secondary to RP with CRVO is an effective treatment, but it needs to be reinjected.

Long-term outcomes of anti-VEGF treatment of macular oedema due to retinal vein occlusions

PURPOSE

retinal vein occlusion (RVO) is classified as either branch (BRVO) or central (CRVO) RVO. The gold standard treatment for macular oedema (MO) secondary to RVO is intravitreal anti-vascular endothelial growth factor (anti-VEGF) injections. Our study aimed to compare ranibizumab and aflibercept outcomes over a maximum follow-up of five years.

METHODS

this retrospective study assessed treatment-naïve RVO patients. Active disease was treated with three loading injections followed by a pro-re-nata (PRN) regimen of an anti-VEGF agent. Visual outcomes and injection frequency were analyzed, with patients stratified according to RVO subtype, anti-VEGF agent used, baseline vision, and age.

RESULTS

316 CRVO-affected eyes and 467 BRVO-affected eyes were analysed. Visual benefits between different treatments did not significantly differ, except in year 1 in ranibizumab-treated BRVO eyes. However, aflibercept-treated CRVO and BRVO eyes required significantly fewer injections during the follow up period. Furthermore, our results confirm that younger patients achieve better visual outcomes with fewer intravitreal injections. Overall, half of our patients did not require further injections after 1 year from diagnosis.

CONCLUSION

the results demonstrate that anti-VEGF treatment of RVO benefits vision for up to 5 years. Our findings are the first to suggest that compared to ranibizumab, fewer aflibercept injections may be required over five years follow up. Prospective randomised trials are needed to confirm this, alongside further attention to OCT scan features and the effect of patient demographics on treatment outcomes.

Assessment of Systemic Immune-inflammation Index Levels in Patients with Retinal Vein Occlusion

PURPOSE

To assess the predictive value of inflammatory markers calculated from complete blood counts in patients with retinal vein occlusion (RVO).

METHODS

This was a retrospective cross-sectional study with a total of 56 RVO patients and 56 age- and gender-matched controls involved. All subjects went through a routine ocular examination, and the peripheral venous blood samples were collected to analyze the differences in inflammatory markers between groups.

RESULTS

The systemic immune-inflammation index (SII) and neutrophil-to-lymphocyte ratio (NLR) values were significantly higher in RVO patients than those in the controls (p=0.002, p=0.004, respectively). According to the receiver operating characteristic (ROC) curve analysis, the areas under the curve (AUC) of SII was 0.666. The AUC of NLR was 0.657.

CONCLUSION

As a novel inflammatory indicator, SII is a more promising indicator than NLR and PLR in the prediction of RVO development.

Association between Statins and Retinal Vascular Occlusion: A Population-Based Cohort Study

Retinal vascular occlusion (RVO), including retinal arterial occlusion and retinal vein occlusion, is a common retinal vascular disease that causes visual disturbance. The exact pathogenesis of RVO remains unclear. In all types of RVO patients, hyperlipidemia is more than twofold more common than in controls. Statins have been used to control blood cholesterol levels and have been found to reduce the risk of cardiovascular morbidity and mortality. Moreover, the immunomodulatory functions of statins may play a role in treating inflammatory diseases. This study aimed to evaluate whether patients taking statins have a lower risk of developing RVO compared to patients not taking statins. Adult patients with statins usage on the index date identified from the Taiwan National Health Insurance Research Database (NHIRD) between 2000 and 2013 were included. A threefold matched group was selected using age, sex, and year of index date for comparison. During the mean follow-up period of 12.87 ± 1.88 years, the cumulative incidence of RVO was significantly lower in the statin-user group (29.96 per 105 person-years [PYs]) than in the non-statin-user group (39.35 per 105 PYs). The results showed a lower cumulative incidence rate of RVO in patients prescribed statins than in those not prescribed statins (log-rank test, p = 0.020). The adjusting hazard ratio (HR) was significantly greater for RVO in the statin-user group (adjusted HR, 0.704; 95% CI, 0.591-0.873). Statin users had a decreased risk for all types of RVO development, including central retinal artery occlusion, arterial branch occlusion, central retinal vein occlusion, and branch retinal vein occlusion. In conclusion, patients undergoing statin treatment have a lower risk of developing RVO compared to patients not taking statins.

The Nationwide Incidence of Retinal Vein Occlusion Following Dialysis due to End-stage Renal Disease in Korea, 2004 through 2013

BACKGROUND

We investigated the incidence and risk of retinal vein occlusion (RVO) in end-stage renal disease (ESRD) patients on dialysis in Korea.

METHODS

In this nationwide cohort study, we used Korean National Health Insurance Service data between 2004 and 2013 for analysis. ESRD patients who started dialysis from 2004 to 2013 and an equal number of controls were selected through propensity score matching. RVO incidence in both cohorts were calculated for 2004-2013 using washout data from 2003. The multivariable Cox proportional hazards model was used to assess the risk of RVO in dialysis cohort. The Kaplan-Meier method was used to generate the cumulative RVO incidence curve. Whether the dialysis modality affects the development of RVO was also evaluated.

RESULTS

In this study, 74,551 ESRD patients on dialysis and the same number of controls were included. The incidence of RVO was significantly higher in the dialysis cohort than in the control cohort (dialysis = 7.3/1,000 person-years [PY]; control = 1.9/1,000 PY; P < 0.001). The cumulative-incidence of RVO was also significantly higher in the dialysis cohort than in the control cohort (P < 0.001; log-rank test). However, there was no significant difference in the incidence of RVO between the two dialysis methods (P = 0.550; log-rank test).

CONCLUSION

This study provided epidemiological evidence that receiving dialysis for ESRD could increase the risk of developing RVO. We also found a rapid increase in the incidence of RVO with a longer dialysis period. These results strengthen the relationship between retinal vascular disease and renal function.

Sodium-Glucose Cotransporter 2 Inhibitors and Risk of Retinal Vein Occlusion Among Patients With Type 2 Diabetes: A Propensity Score-Matched Cohort Study

OBJECTIVE

To assess the association between use of sodium-glucose cotransporter 2 (SGLT2) inhibitors and retinal vein occlusion (RVO) using data from the National Health Insurance Service in South Korea.

RESEARCH DESIGN AND METHODS

We used an active comparator, new user design, and nationwide data from 2014 to 2017. Based on a 1:1 propensity score match, we included 47,369 new users of SGLT2 inhibitors and 47,369 users of other glucose-lowering drugs (oGLDs). In the matched sample, we used the Cox proportional hazards model to estimate hazard ratios (HRs) with 95% CIs for developing RVO. Based on the main outcome, exploratory subgroup analyses were undertaken.

RESULTS

During a follow-up of 2.57 years, the incidence rate of RVO was 2.19 and 1.79 per 1,000 person-years in patients treated with SGLT2 inhibitors and oGLDs, respectively. The new use of SGLT2 inhibitors was associated with an increased risk of RVO compared with oGLD use (HR 1.264 [95% CI 1.056, 1.513]). In the subgroup analyses, a significant interaction with SGLT2 inhibitors was observed for age and estimated glomerular filtration rate (eGFR); the HR for RVO was higher in patients aged ≥60 years and those with eGFR <60 mL/min/1.73 m2 than in others.

CONCLUSIONS

In a matched cohort study, we found that SGLT2 inhibitors were associated with a significantly increased risk of RVO. Older patients and those with chronic kidney disease were at higher risk for RVO.

Treatment of retinal vein thrombosis: what about anticoagulants?

Retinal vein occlusion is an important cause of vision loss. The current treatment options are mainly directed to the prevention of neovascular complications and few studies have addressed to potential use of anticoagulant agents and other interventions targeting the coagulation system. Herein we review the general aspects of this condition focusing on the potential benefits of anticoagulant treatment.

Quality of Life among Patients with Retinal Vein Occlusion: A Case-Control Study

Purpose: The purpose of this study was to evaluate health-related quality of life in patients with retinal vein occlusion (RVO) and investigate the possible risk factors for poor quality of life in patients with RVO.Methods: Participants in the study were 67 patients with RVO, 42 male and 25 female, mean-aged 73.1 ± 10.9 years, and 70 sex- and age-matched controls. Demographic data, lifestyle factors and medical history were recorded. All patients underwent best-corrected visual acuity measurement, dilated fundoscopy and optical coherence tomography. All participants completed two questionnaires assessing quality of life (EQ-5D, NEI VFQ-25). Risk factors for health-related quality of life in RVO patients were investigated.Results: Patients with RVO exhibited significantly lower composite score for VFQ-25 compared to controls (74.1 ± 3.8 vs. 91.7 ± 3.9 for patients and controls, respectively, p < .001). In addition, RVO patients had significantly lower EQ-5D Index score compared to controls (0.88 ± 0.15 vs. 0.92 ± 0.12 for patients and controls, respectively, p = .043). Risk factors associated with quality of life in patients with RVO were found the alcohol consumption, the presence of thyroidopathy, coagulation disorders, visual acuity in the eye with RVO, central retinal thickness, the type of edema, the presence of ischemia and the condition of external limiting membrane. In multivariate analysis, only alcohol consumption and visual acuity in the eye with RVO were found to be independent risk factors, affecting quality of life in RVO patients.Conclusions: Patients with RVO presented lower quality of life in comparison with controls. Potential risk factors should be taken into account and their early detection may improve quality of life in such patients and lead to targeted health policies.

[Blood, where no blood should be]

Intraocular ischemia can lead to an overexpression of vascular endothelial growth factor (VEGF). This in turn can lead to neovascularization in the anterior and/or posterior segment of the eye, e.g. in the iris or the retina. This article reports a case of neovascularization of the lens due to occlusion of the central retinal vein.

Medical Compliance of Fibrate and the Decreased Risk of Age-Related Macular Degeneration in Dyslipidemia-Related Diseases: A Population-Based Cohort Study

The purpose of the current study is to evaluate the incidence of age-related macular degeneration (AMD) in dyslipidemia-related diseases with or without the use of fibrate. Patients were defined as dyslipidemia-related diseases according to the diagnostic code and lab exam arrangement, then the population was divided into those with fibrate application and those without via 1:2 ratios of propensity-score matching. The primary outcome is the development of AMD after dyslipidemia-related diseases by the Cox proportional hazard regression. Besides, the relationship between the medical compliance of fibrate, presented as medical possession ratio (MPR), and the AMD development was also analyzed. A total of 22,917 patients and 45,834 individuals were enrolled in the study and control groups. There were 572 and 1181 events of any AMD development in the study and control groups which showed identical risk of AMD (aHR: 0.94, 95% CI: 0.85–1.04). However, a reduced risk of any AMD was found in those patients reached a baseline MPR more than 20% (aHR: 0.729, 95% CI: 0.599–0.887, p = 0.0016) and overall MPR more than 5% three years after the diagnosis of dyslipidemia-related diseases (aHR: 0.712, 95% CI: 0.557–0.909, p = 0.0065). Besides, a lower risk of dry-AMD was also found in those patients with the above conditions (aHR: 0.736, 95% CI: 0.599–0.906, p = 0.0038 and aHR: 0.721, 95% CI: 0.557–0.934, p = 0.0133, respectively). In conclusion, the use of fibrate with fair initial medical compliance will decrease the incidence of AMD in patients with dyslipidemia-related diseases, especially for the development of dry-AMD.

Risk factors for central retinal vein occlusion in young adults

Purpose:

Several risk factors have been identified for central retinal vein occlusion (CRVO) in older population. CRVO in young is uncommon, and the risk factors for this group are unclear. This large retrospective, cross-sectional study used the National Inpatient Sample (NIS) database to evaluate the risk factors for CRVO in patients 18 to 40 years of age.

Methods:

The 2002 to 2014 NIS database was used. All patients 18 to 40 years of age with a primary diagnosis of CRVO were identified. Age- and gender-matched non-CRVO controls were randomly selected. The primary outcome was identification of risk factors for CRVO. Chi-square analysis and Firth logistic regression were performed with IBM SPSS 23 and R packages versions 3.4.3, respectively. p < 0.05 was considered significant.

Results:

A total of 95 weighted young CRVO patients were identified. The average age was 31.44 ± 6.41 years with no gender predilection. Systemic and ocular conditions found to have statistically significant associations with CRVO included primary open-angle glaucoma (POAG) (OR 836.72, p < 0.001), retinal vasculitis (OR 705.82, p < 0.001), pseudotumor cerebri (OR 35.94, p < 0.001), hypercoagulable state (OR 25.25, p < 0.001), history of deep vein thrombosis/pulmonary embolism (DVT/PE) (OR 21.88, p < 0.001), and hyperlipidemia (OR 3.60, p = 0.003).

Conclusion:

The most significant risk factors for CRVO in young adults were POAG, retinal vasculitis, and pseudotumor cerebri. Hypercoagulable states and DVT/PE were also associated with CRVO in this population. Systemic inflammatory conditions were not associated with CRVO. Traditional risk factors such as hypertension and diabetes did not pose significant risks, whereas hyperlipidemia was deemed a significant risk factor.

Analysis of intravitreal bevacizumab treatment for macular oedema due to retinal vein occlusion

PURPOSE

Our aim was to analyse the clinical effect of intravitreal bevacizumab treatment for macular oedema due to central/branch retinal vein occlusion (CRVO/BRVO). The end points were final best-corrected visual acuity (BCVA), BCVA improvement, final central 1-mm macular subfield thickness (CST) and change in CST.

METHODS

Our study included 34 CRVO and 25 BRVO patients. Patients received intravitreal bevacizumab (IVB) treatment at our department. Our control group consisted of 50 CRVO and 30 BRVO patients, who had not received this treatment because their disease developed before the anti-VEGF treatment became available. For statistical analysis, two-sample t-test, Pearson's correlation, and ANOVA were used. The level of significance was defined at p < 0.05.

RESULTS

With the two-sample t-test we found significant improvement of BCVA in the IVB-treated group (CRVO: 0.171 ± 0.270, p1 = 3.25×10-4; BRVO: 0.215 ± 0.282, p2 = 5.52×10-4). The difference in BCVA improvement was also significant compared to the control group (CRVO: p1 = 3.46×10-4; BRVO: p2 = 0.003). Significant decrease was observed in the CST in the treated group (CRVO: -345.114 ± 280.577, p1 = 6.94×10-9; BRVO: -151.875 ± 174.341, p2 = 1.67×10-4). In case of BRVO patients the final BCVA was significantly better in the treated group (0.617 ± 0.334) compared to the control group (0.406 ± 0.357), p = 0.016.

CONCLUSION

IVB treatment results in significantly better final visual acuity and leads to significantly increased BCVA improvement compared to patients with RVO-induced macular oedema receiving no treatment.

Ophthalmology in Critical Care

Ophthalmic disease encountered in the intensive care unit (ICU) has a wide spectrum of prevalence and severity. Prolonged exposure of the cornea is common and preventable. Trauma, glaucoma, infection, vascular disease, and burns are among the potential causes of vision loss. Patients are predisposed to ocular complications by the ICU environment and critical illness itself. Critically ill patients require prioritization of life-sustaining interventions, and less emphasis is placed on ophthalmic disease, leading to missed opportunities for vision-saving intervention. It is therefore imperative for intensivists, nurses, and other providers to have an increased awareness and understanding of the broad range of ocular conditions potentially seen in the ICU.

Intravitreal Dexamethasone Implant as a Sustained Release Drug Delivery Device for the Treatment of Ocular Diseases: A Comprehensive Review of the Literature

Drug delivery into the vitreous chamber remains a great challenge in the pharmaceutical industry due to the complex anatomy and physiology of the eye. Intravitreal injection is the mainstream route of drug administration to the posterior segment of the eye. The purpose of this review is to assess the current literature about the widening use of the intravitreal 0.7 mg dexamethasone (Dex) implant, and to provide a comprehensive collection of all the ocular disorders that benefit from Dex administration. Although anti-vascular endothelial growth-factors (VEGFs) have been largely indicated as a first-choice level, the Dex implant represents an important treatment option, especially in selected cases, such as vitrectomized eyes or patients in whom anti-VEGF failed or are contraindicated. In this article, the safety profile as well as the list of the possible complications related to intravitreal Dex injection are also discussed.

Hypertension and multiple cardiovascular risk factors increase the risk for retinal vein occlusions: results from the Gutenberg Retinal Vein Occlusion Study

OBJECTIVE

Although several risk factors for retinal vein occlusion (RVO) are known, what triggers RVO is unclear in many cases. We aimed to evaluate the relevance of multiple risk factors in patients with RVO.

METHODS

The Gutenberg RVO Study is an observational case-control study that assessed thrombophilic, cardiovascular, ophthalmic, and drug-related risk factors in participants with RVO and the same number of matched controls. Conditional logistic regression analysis was chosen to estimate the risk of RVO due to several risk factors.

RESULTS

Of 92 patients with RVO, 46 (50%) had central RVO, 31 (33.7%) had branch RVO, and 15 (16.3) had hemi-RVO. Systemic hypertension was associated with RVO [any RVO: odds ratio (OR): 1.81; 95% confidence interval (CI): 1.14-2.88; branch RVO: OR: 2.56; 95% CI: 1.08-6.10]. The most frequent combinations of risk factors were hypertension with dyslipidemia (33 of 92, 35.9%) and hyperhomocysteinemia and high levels of factor VIII (10 of 92, 10.9%). An increase in the risk sum score by one additional risk factor corresponded to ORs of 1.74 (95% CI: 1.31-2.32) for cardiovascular risk factors, 1.38 (95% CI: 1.04-1.82) for thrombophilic risk factors, and 1.43 (95% CI: 1.20-1.70) for the total number of risk factors for RVO.

CONCLUSION

Cardiovascular risk factors are more important than other risk factors for the presence of RVO. The risk of RVO increased by approximately 40% with any additional risk factor and by 70% with any additional cardiovascular risk factor.

Current Best Clinical Practices-Management of Retinal Vein Occlusion

Retinal vein occlusion (RVO) is the second most common cause of vision loss from retinal vascular diseases in adults in the United States. Visual loss arises as a result of a host of factors, including macular ischemia and macular edema. Primary antivascular endothelial growth factor therapy is the current standard of care, with level I evidence demonstrating sustained visual gains up to 2 years after treatment in both branch and central RVO. Prompt antivascular endothelial growth factor therapy is important because delays in treatment yield lesser visual gains. Steroid therapy also improves visual outcomes in RVO but with higher rates of adverse effects, including cataract formation and ocular hypertension. Although the treatment burden can be high, these drugs have collectively revolutionized treatment outcomes in this disease state, providing improved visual outcomes over previous laser therapies.

Assessment of cerebral low-frequency oscillations in patients with retinal vein occlusion: a preliminary functional MRI study

BACKGROUND

There is increasing evidence that patients with retinal vein occlusion exhibit cerebral vascular changes and are at an increased risk of stroke. However, it remains unknown whether patients with retinal vein occlusion exhibit changes in intrinsic brain activity.

PURPOSE

This study investigated intrinsic brain activity changes in patients with retinal vein occlusion by assessing the amplitude of low-frequency fluctuations.

MATERIAL AND METHODS

Forty-five patients with retinal vein occlusion (22 men, 23 women, mean age 56.55 ± 6.97 years) and 43 healthy controls (13 men, 30 women; mean age 53.53 ± 8.19 years) closely matched in age, sex, and education level underwent resting-state MRI scans. The amplitude of low-frequency fluctuation method was used to compare intrinsic brain activity between the two groups.

RESULTS

Compared with healthy controls, patients with retinal vein occlusion exhibited significantly lower amplitude of low-frequency fluctuation values in the left middle occipital gyrus, right middle occipital gyrus, and right calcarine. However, patients with retinal vein occlusion showed significantly higher amplitude of low-frequency fluctuations in the bilateral cerebellum 6, right hippocampus, left insula, and left fusiform (voxel-level P < 0.01, Gaussian random field correction, cluster-level P < 0.05).

CONCLUSION

Our results demonstrated that patients with retinal vein occlusion showed abnormal spontaneous neural activities in the visual cortices, cerebellum, and Papez circuit, which might indicate impaired vision, cognition, and emotional function in patients with retinal vein occlusion. These findings offer important insights into the neural mechanism of retinal vein occlusion.

Intravitreal injection of conbercept combined with retinal photocoagulation on macular edema secondary to branch retinal vein occlusion

Effects of Conbercept combined with retinal photocoagulation on macular edema secondary to branch retinal vein occlusion (BRVO) were investigated. A total of 98 patients (98 eyes) with macular edema secondary to BRVO were collected. The central macular thickness (CMT), incidence rate of complications after treatment and best corrected visual acuity (BCVA) were recorded. Also the factors affecting visual recovery of patients were analyzed. At 1 week, 1 month, 3 months and 6 months after treatment, the BCVA in both groups was significantly superior to that before treatment (P<0.05). In the combination group and laser group, the logarithm of the minimum angle of resolution (logMAR) of BCVA increased from 0.84±0.47 to 0.34±0.10 and from 0.89±0.49 to 0.45±0.14, and CMT declined from 559.5±152.7 to 267.8±19.8 µm and from 570.3±172.6 to 314.7±18.4 µm. It was observed that at 1 week, 1 month, 3 months and 6 months after treatment, the BCVA in combination group was obviously better than that in laser group (P=0.008, P<0.001, P=0.004, P<0.001, respectively), while CMT in combination group was obviously smaller than that in laser group (P=0.009, P=0.002, P<0.001, P<0.001). Conbercept with retinal photocoagulation can effectively improve the visual acuity and reduce the CMT. The visual recovery of patients after treatment is related to the BCVA before treatment, decreased value of CMT at 1 month after treatment and integrity of external limiting membrane (ELM).

Real-World Data: Ranibizumab Treatment For Retinal Vein Occlusion In The OCEAN Study

Purpose

The non-interventional OCEAN study (NCT02194803) evaluated frequency and monitoring of ranibizumab injections for retinal vein occlusion (RVO) in routine practice in Germany.

Methods

RVO patients (including branch and central RVO (BRVO/CRVO)) receiving ranibizumab were included. Best-corrected visual acuity (BCVA) testing, imaging and treatment were performed at the investigators’ discretion and documented over 24 months.

Results

Overall, 744 RVO patients (27% BRVO, 16% CRVO, remaining unspecified RVO) were included. For 74% of patients, data were available for the 12-month visit and for 56% for the 24-month visit. Mean baseline BCVA was 52.0 Early Treatment for Diabetic Retinopathy Study (ETDRS) letters (BRVO: 55.9, CRVO: 43.9). BCVA improved rapidly within the first 3 months, reaching 64.3 letters at 12 months and 64.7 at 24 months. CRVO patients showed less improvement than those with BRVO. Patients received a median of 4 (5) injections over 12 (24) months, with 100% of patients receiving injections at baseline, 70% at Month 1 and 81% at Month 2. Overall, 40% of patients demonstrated a ≥15 letter increase within the first 3 months (42% BRVO, 46% CRVO). Patients with low initial BCVA (<50 letters) showed greater improvement than patients with higher baseline BCVA. Due to considerable loss to follow-up, the number of injections and optical coherence tomography (OCT) examinations were not associated with the change in BCVA.

Conclusion

Patients with RVO in routine practice in Germany received fewer injections and fewer OCT examinations than in clinical trials. CRVO patients showed less and later improvement compared to BRVO patients.

Neutrophil/Lymphocyte Ratio and Platelet/Lymphocyte Ratio in Branch Retinal Vein Occlusion

Purpose. To evaluate the neutrophil/lymphocyte ratio (NLR) and the platelet/lymphocyte ratio(PLR) value in the development of branch retinal vein occlusion (BRVO)patients. Methods. 81 patients with BRVO and 81 age and sex-matched subjects were recruited as the control group. The BRVO diagnosis was confirmed under comprehensive ophthalmologic examinations. NLR and PLR parameters obtained from peripheral blood were recorded. Results. Both the mean NLR and PLR was significantly higher in the BRVO group compared with the control group (p < 0.001). In ROC analysis, the AUC for NLR was 0.82, and NLR of >2.48 predicted BRVO with a sensitivity of 58% and specificity of 98%. The AUC for PLR was 0.78, and PLR of >110.2 predicted BRVO with a sensitivity of 72% and specificity of 72%. Conclusion. The current study demonstrated that BRVO patients had increased NLR and PLR levels compared with control subjects. The NLR and PLR may be used as independent predictors for identifying risk for the development of BRVO.

OCT angiography features associated with macular edema recurrence after intravitreal bevacizumab treatment in branch retinal vein occlusion

We aimed to evaluate the relationship between the capillary abnormalities including nonperfusion area (NPA) in optical coherence tomography angiography (OCTA) images and the recurrence of macular edema (ME) secondary to branch retinal vein occlusion (BRVO) after intravitreal injection of anti-vascular endothelial growth factor (anti-VEGF; bevacizumab). The records of 40 patients who underwent intravitreal bevacizumab injection for ME secondary to BRVO and had at least six months of follow-up were reviewed. Central retinal thickness (CRT; μm) and macular edema type were evaluated prior to treatment. After ME resolution, nonperfusion areas in the 1 mm (NPA1) and 1–3 mm (NPA3) zones on the Early Treatment Diabetic Retinopathy Study (ETDRS) circle within the superficial capillary plexus (SCP) and deep capillary plexus (DCP) were measured using OCTA images. Furthermore, other microvascular abnormalities in the both SCP and DCP were compared between groups. ME recurred in 25 of 40 (62.5%) eyes. The NPA1 of the SCP and DCP (p = 0.002, 0.004, respectively), NPA3 of the SCP and DCP (p = 0.002, 0.008, respectively), and initial CRT (p = 0.022) differed significantly between eyes with and without ME recurrence. In multivariate logistic regression analyses, the NPA1 of the DCP (OR: 344.718; p = 0.029) and NPA3 of the SCP (OR: 4.072; p = 0.018) were significantly associated with ME recurrence. Other microvascular abnormalities were not significantly different between two groups. The central NPA and parafoveal NPA of the SCP in OCTA images correlated strongly with ME recurrence in BRVO patients after intravitreal anti-VEGF injection.

Etiological factors in young patients with Retinal Vein Occlusion

Objective:

To present the etiological factors of patients with Retinal Vein Occlusion (RVO) under the age of 50 years.

Methods:

The study was conducted at Ege University Medicine Faculty Department of Ophthalmology. The clinical records of patients with RVO under the age of 50 seen between January 2014 and March 2018 were analyzed retrospectively. Forty patients comprised the study. Detailed ophthalmologic examination was performed. Past medical history, drug use, thrombophilic features, hyperviscosity syndromes and pathologies that may cause vasculitis were noted.

Results:

Forty patients, 22 (55%) male and 18 (45%) female, were included. Mean age was 41.6 ± 10.01 years. Mean intraocular pressure and best-corrected visual acuity were 16.8 ± 5.47mmHg and 0.76 ± 0.64 logMAR, respectively. Hyperhomocystenemia (15 patients, 37.5%), Behçet’s disease (three patients, 7.5%), diabetes and/or hypertension (16 patients, 40%), methylenetetrahydrofolate reductase gene mutation (11 patients, 27.5%), prothrombin gene mutation (four patients, 10%) and factor V Leiden mutation (five patients, 12.5%) were present among the patients as etiological factor. Multiple etiological factors were detected in 11 (27.5%) patients. Factor V Leiden mutation and methylenetetrahydrofolate reductase gene mutation were detected in one patient (2.5%) with Behçet’s disease. Four patients with diabetes and/or hypertension also had hyperhomocystenemia and one of them had additionally prothrombin gene mutation. Two patients with methylenetetrahydrofolate reductase gene mutation also had a factor V Leiden mutation and one of them had additionally a prothrombin gene mutation. Three patients with methylenetetrahydrofolate reductase gene mutation also had hyperhomocystenemia and one patient with prothrombin gene mutation also had methylenetetrahydrofolate reductase gene mutation.

Conclusions:

Etiological factors that might result in RVO in young individuals should be investigated in detail. Targeted therapies may help to prevent development of new RVOs and potential vascular problems in other organs.

Comparison of systemic conditions at diagnosis between central retinal vein occlusion and branch retinal vein occlusion

Objective

To compare systemic conditions at the time of diagnosis between patients with central retinal vein occlusion (CRVO) and branch retinal vein occlusion (BRVO).

Design

This study included patients diagnosed with CRVO or BRVO between February 2009 and August 2017 at three branch hospitals of Hallym University Medical Center. Demographic and anthropometric variables, systemic comorbidity profiles, and laboratory findings at diagnosis were collected from a clinical data warehouse system, and were compared between the CRVO and BRVO groups.

Result

Four hundred and seventeen patients with CRVO and 1,511 patients with BRVO were included. The mean age was 61.8 ± 13.9 years, which was comparable between two groups (P = .332). Female proportion was higher in the BRVO group (55.0%) than in the CRVO group (48.0%; P = .013). Diabetes mellitus (P = .017) and chronic kidney disease (P = .004) were more prevalent in the CRVO group. Serum homocysteine level was abnormally high in 23.5% of CRVO patients and in 8.4% of BRVO patients (P < .001). Blood urea nitrogen and serum creatinine levels were abnormally elevated in more subjects with CRVO (P = .002).

Conclusion

CRVO is associated with higher prevalence of diabetes mellitus and chronic kidney disease, as well as with elevated serum homocysteine level. These results might suggest a difference between the pathophysiologies of CRVO and BRVO.

Evaluation of lamina cribrosa thickness in patients diagnosed with central retinal vein occlusion

PURPOSE

To evaluate the thickness of lamina cribrosa (LC) in both eyes of patients with unilateral central retinal vein occlusion (CRVO) and to compare with eyes of age-matched healthy control subjects.

METHODS

This prospective case-control study included a total of 38 patients with unilateral CRVO and 42 healthy control subjects. The LC thickness was measured at the center of the optic disc using an enhanced depth imaging with the spectral domain optical coherence tomography in both eyes of patients with unilateral CRVO and eyes of healthy control subjects. The LC thickness of CRVO patients was evaluated one month after dexamethasone intravitreal implant (Ozurdex) injection.

RESULTS

The mean LC thickness in affected eyes of patients with CRVO was significantly thinner than that of the healthy eyes (204.4 ± 8.8 and 228.0 ± 7.1 μm, p < 0.001, respectively). Also, the unaffected fellow eyes had significantly thinner LC compared with eyes of healthy subjects (205.3 ± 9.3 and 228.0 ± 7.1 μm, p < 0.001, respectively). There was no statistically significant difference in the thickness of LC between the affected and unaffected fellow eyes (p = 0.669).

CONCLUSIONS

The LC thickness in both eyes of CRVO patients was thinner than that of the healthy eyes. This finding suggests that thin LC may contribute to the development of CRVO as an ocular risk factor in addition to systemic factors.

Rapid progression of cataract to mature stage after intravitreal dexamethasone implant injection: a case report

Background

This study aims to report a case of rapid progression of cataract to mature stage after intravitreal dexamethasone implantation for macular edema due to branch retinal vein occlusion.

Case presentation

A 59-year-old Korean male with complaints of sudden metamorphopsia and reduced visual acuity for three days in the left eye was referred to our clinic. Ophthalmological investigations included fundus photography, fluorescein angiography, and optical coherence tomography. In the left eye, branch retinal vein occlusion with macular edema was observed. We performed intravitreal dexamethasone implantation in the left eye three times within a period of one year. One week after the third intravitreal dexamethasone implantation, grade 1 posterior subcapsular opacity and raised intraocular pressure were observed in the left eye. Three weeks later, mature cataract was observed in the left eye. We performed cataract surgery along with intravitreal ranibizumab injection in the left eye. The procedure was uneventful, and the visual acuity improved postoperatively.

Conclusions

Posterior subcapsular cataract developed due to intravitreal dexamethasone implantation can progress rapidly to mature stage. Therefore, short-term follow-up examinations may be necessary for early diagnosis and treatment of this complication.

Long-term management of non-ischemic central retinal vein occlusion with fluocinolone acetonide intravitreal implant 190 μg (ILUVIEN®)

INTRODUCTION

Macular edema after central retinal vein occlusion is a common cause of vision loss. Upregulation of vascular endothelial growth factor and higher levels of inflammatory mediators have been involved in the pathogeny of the macular edema in central retinal vein occlusion.

CASE REPORT

The authors report a case with non-ischemic central retinal vein occlusion that was successfully treated with a single sustained-release fluocinolone acetonide intravitreal implant. After a course of repeated injections of shorter-acting corticosteroid, the affected eye presented a visual acuity of 20/200 and a central subfield foveal thickness of 587 µm. After fluocinolone acetonide in intravitreal implant and during a follow-up period of 12 months, a continuous and sustained increase in visual acuity until 20/25 with significant anatomical improvements and an acceptable safety profile was observed.

CONCLUSION

These results, demonstrate that fluocinolone acetonide intravitreal implant might be an effective treatment option in macular edema secondary to non-ischemic central retinal vein occlusion.