Assessment of Serum Atherogenic Indices and Insulin Resistance in Retinal Vein Occlusion.

Objectives: This study aimed to investigate serum atherogenic indices as novel cardiovascular risk factors associated with retinal vein occlusion (RVO). Materials and Methods: This retrospective case-control study included 57 patients with newly diagnosed RVO whose plasma lipid profile (low-density lipoprotein cholesterol [LDL-C], high-density lipoprotein cholesterol [HDL-C], total cholesterol [TC], and triglycerides [TG]) and insulin resistance were examined. Serum atherogenic indices (LDL-C/HDL-C, TC/HDL-C, TG/HDL-C, and non-HDL-C/HDL-C ratios) and presence of insulin resistance were compared between the patients and 63 healthy subjects. Cut-off values were determined by receiver operating characteristic curve analysis. Results: The mean age of the RVO patients was 63.7±9.4 years. Plasma levels of LDL-C, HDL-C, TC, and TG showed no significant difference between the patient and control groups (p>0.05). However, LDL-C/HDL-C, non-HDL-C/HDL-C, and TC/HDL-C ratios were higher in the RVO group compared to healthy subjects (p=0.015, p=0.036, and p=0.015, respectively). Fasting insulin concentrations, plasma insulin, and homeostasis model assessment of insulin resistance (HOMA-IR) index were higher in the RVO patients compared to controls (p=0.003, p=0.001, and p=0.001, respectively). Conclusion: LDL-C/HDL-C, TC/HDL-C, and non-HDL-C/HDL-C ratios were found to be increased in RVO. Compared to the traditional plasma lipid profile, serum atherogenic indices were found to be superior predictors of RVO development. Measurement of HOMA-IR index should be taken into consideration in the evaluation of insulin resistance. High serum atherogenic indexes in RVO patients reveal the need to take precautions against the risk of cardiovascular disease and stroke.

The association of neutrophil-lymphocyte ratio and platelet-lymphocyte ratio with retinal vein occlusion: a systematic review and meta-analysis.

The neutrophil-lymphocyte ratio (NLR) and platelet-lymphocyte ratio (PLR) are emerging haematological inflammatory biomarkers. However, their significance in retinal vein occlusion (RVO) and its subtypes, branch and central RVO (BRVO and CRVO, respectively), is uncertain. This systematic review and meta-analysis aimed to clarify the association of NLR and PLR with RVO. We searched MEDLINE (Ovid), EMBASE (Ovid) and the Cochrane Library for studies investigating the association of NLR and PLR with RVO from inception to 2 December 2020. We used random-effects inverse-variance modelling to generate pooled effect measures. We used bivariate Bayesian modelling to meta-analyse the ability of NLR and PLR to differ between individuals with and without RVO and performed meta-regression and sensitivity analyses to explore inter-study heterogeneity. Eight studies published encompassing 1059 patients were included for analysis. Both NLR and PLR were significantly elevated in RVO, with pooled mean differences of 0.63 (95% confidence interval (CI) 0.31-0.95) and 21.49 (95% CI 10.03-32.95), respectively. The pooled sensitivity, specificity and area under the Bayesian summary receiver operating characteristic curve were, respectively, 0.629 (95% credible interval (CrI) 0.284-0.872), 0.731 (95% CrI 0.373-0.934) and 0.688 (95% CrI 0.358-0.872) for NLR; and 0.645 (95% CrI 0.456-0.779), 0.616 (95% CrI 0.428-0.761) and 0.621 (95% CrI 0.452-0.741) for PLR. Mean and variability of age and diabetes mellitus prevalence partially explained between-study heterogeneity. NLR and PLR are significantly elevated in RVO. Future research is needed to investigate the potential prognostic value and independence of these findings.

The association between circulating neutrophil extracellular trap related biomarkers and retinal vein occlusion incidence: A case-control pilot study.

Retinal vein occlusion (RVO) is the second most common retinal vascular disorders and causes visual damage in a large population. Neutrophil extracellular traps (NETs) formation (NETosis) is an important cause of vascular diseases, however, the association between NETs related biomarkers and RVO development remained unclear. In this pilot study, a total of 77 RVO cases and 48 controls were included between Jan 2020 and July 2020. Besides, the circulating levels of three NETs related markers, cell-free DNA (cfDNA), myeloperoxidase (MPO)-DNA and citrullinated histone H3 (H3Cit), were detected in all the participants and thus the association between NETosis and RVO incidence was analyzed. Advanced assays were conducted to investigate the inflammation and thrombosis related biomarkers in RVO cases with higher or lower NETs biomarkers. When the results were considered, it was found that NETs biomarkers, including cfDNA, MPO-DNA and H3Cit, were increased in the RVO cases comparing with the controls (P < 0.05). Through the receiver operating characteristic (ROC) analyses, we found that circulating NETs related biomarkers demonstrated potential diagnostic effects for RVO and the AUCs of plasma cfDNA, MPO-DNA and H3Cit were 0.859, 0.871 and 0.928, respectively (P < 0.001). Through analyzing the correlations between circulating NETs markers and RVO stages and durations, inflammatory markers as well as thrombotic indexes, it was found that NETs were related with the RVO subtypes, inflammatory status and thrombus formation. In conclusion, the plasma NETs remnants are significantly increased in RVO cases. Besides, advanced studies demonstrate that inflammation as well as thrombus formation might be involved in this association.

ASSOCIATION BETWEEN PLATELET INDICES AND RETINAL VEIN OCCLUSION: A Systematic Review and Meta-Analysis.

PURPOSE: Platelet count, mean platelet volume, platelet distribution width, and plateletcrit are standard indices of platelet activation that have been studied in retinal vein occlusion (RVO) and its subtypes: branch retinal vein occlusion and central retinal vein occlusion. This systematic review and meta-analysis aimed to assess the association between these platelet parameters and RVO. METHODS: We searched for studies investigating the association between these platelet indices and RVO in multiple online databases from inception to August 2020. Mean differences and the associated confidence intervals were obtained and calculated for each included study and pooled using random-effects inverse variance modeling. Meta-regression was used to explore interstudy and intrastudy heterogeneity. RESULTS: Thousand three hundred and twenty-five unique studies were screened, from which 24 studies encompassing 2,718 patients were included. Mean platelet volume and platelet distribution width were significantly elevated in RVO, with pooled mean differences of 0.45 fL (95% CI 0.24-0.66, P < 0.0001) and 1.43% (95% CI 0.57-2.29, P = 0.0011), respectively. Platelet count and plateletcrit were not significantly associated with RVO. Mean platelet volume was also independently elevated in branch retinal vein occlusion and central retinal vein occlusion. CONCLUSION: Mean platelet volume and platelet distribution width are significantly elevated in RVO. Further research is required to explore the independence and potential prognostic significance of these associations.

SERUM LEVELS OF ANTIBODIES AGAINST OXIDATION-SPECIFIC EPITOPES ARE DECREASED IN PATIENTS WITH RETINAL VEIN OCCLUSION.

PURPOSE: Oxidative stress and inflammation have been implicated in the development of retinal vein occlusion (RVO). Oxidation-specific epitopes (OSEs) represent products of oxidative stress that can trigger vascular inflammation and thrombosis. Natural occurring antibodies have been shown to bind oxidation-specific epitopes thereby inhibiting their inflammatory potential and promoting their removal. METHODS: This prospective cross-sectional study included 270 patients with RVO and 81 in-hospital control patients. We measured three types of serum levels of oxidation-specific epitope-specific immunoglobulin M and immunoglobulin G antibodies (anti-copper-oxidized LDL [CuOx-LDL], antiphosphocholine [PC], anti-malondialdehyde-modified LDL [MDA-LDL]). History of arterial hypertension, hyperlipidemia, myocardial infarction, diabetes mellitus, stroke, smoking status, and several laboratory parameters were determined to control for potential confounders. RESULTS: Compared with controls, patients with RVO had significantly lower levels of immunoglobulin M and immunoglobulin G antibodies against CuOx-LDL and PC, and significantly lower levels of immunoglobulin G but not immunoglobulin M antibodies against MDA-LDL. The association between RVO patients and lower levels of these antibodies prevailed upon multivariable adjustment. CONCLUSION: These prospective data show that antibodies against oxidation-specific epitope are lower in patients with RVO compared with control patients and support the concept that oxidative stress and inflammation play key roles in the development and subsequent complications in RVO.

Change in cardiac troponin T level after intravitreal anti-vascular endothelial growth factor treatment: Prospective pilot study.

BACKGROUND: Evaluate subclinical myocardial injury associated with intravitreal anti-vascular endothelial growth factor therapy by measuring serum high-sensitivity cardiac troponin T. METHODS: This is a prospective pilot comparative study conducted at American University of Beirut Medical Center, Beirut, Lebanon. In total, 40 consecutive patients were randomized to receive either intravitreal bevacizumab or ranibizumab. Patients received three consecutive monthly injections of the assigned drug, then continued treatment as needed. Systemic concentrations of high-sensitivity cardiac troponin T and vascular endothelial growth factor were obtained at baseline, week 9, and week 24. Primary endpoint measure was change in high-sensitivity cardiac troponin T levels compared to baseline. Secondary endpoint measure was change in systemic vascular endothelial growth factor levels. RESULTS: There was no significant difference in high-sensitivity cardiac troponin T levels over time (p = 0.227) within each treatment group and no significant difference between treatments at any time point (p = 0.276). There was a significant decrease in plasma vascular endothelial growth factor levels at week 9 (p = 0.001) and week 24 (p < 0.001) compared to baseline. In the ranibizumab group, vascular endothelial growth factor levels were not significantly different at weeks 9 and 24 compared to baseline (p = 0.708 and p = 0.117, respectively). There was a significant association between the number of bevacizumab injections from weeks 8 to 24 and the decrease in vascular endothelial growth factor levels at week 24 (R = -0.67, p = 0.032). This correlation was not observed in the ranibizumab group (R = -0.341, p = 0.141). CONCLUSION: Repeated intravitreal bevacizumab or ranibizumab did not influence serum high-sensitivity cardiac troponin levels. Intravitreal bevacizumab but not ranibizumab lowered free-systemic vascular endothelial growth factor levels, which was observed in this study to be inversely related to the number of bevacizumab injections.

Assessment of Monocyte/HDL Ratio in Branch Retinal Vein Occlusion.

Purpose: The purpose of this article was to evaluate monocyte count and high-density lipoprotein (HDL) cholesterol levels and their ratio (monocyte/HDL ratio [MHR]) in patients with branch retinal vein occlusion (BRVO).Materials and Methods: A total of 50 participants were included in the study. Participants were divided into two groups: Twenty-five patients diagnosed with BRVO and 25 participants as the control group. Ocular examination findings and hematologic parameters were accessed from the file records and database, retrospectively.Results: The mean MHR was significantly higher in BRVO group compared to the control group (13.4 ± 5.2 vs. 8.1 ± 2.2, p < 0.001). In receiver operating characteristics analysis, the area under the curve for MHR was 0.862, and an MHR of >9.5 predicted BRVO with a sensitivity of 76% and specificity of 70.8%.Conclusion: The present study showed that elevated MHR is significantly associated with BRVO. Therefore, MHR may be a useful marker for the emergence of BRVO.

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.

Mean platelet volume and central retinal vein occlusion in hypertensive patients.

OBJECTIVE: To study the relationship between mean platelet volume (MPV) and central retinal vein occlusion (CRVO) in hypertensive patients. DESIGN: Hospital-based, retrospective, case control design. PARTICIPANTS: The sample group consisted of 100 patients with a known history of hypertension and who are diagnosed with CRVO. The control group consisted of 100 age and sex-matched patients with the sample group and who had a sole history of hypertension without any other systemic diseases and the best corrected visual acuity of 20/20 in both the eyes. METHODS: CRVO was diagnosed based on clinical examination. All cases and control subjects underwent complete ocular examination. MPV, platelet count, hemoglobin, white blood cell count and hematocrit parameters were recorded for both groups. The data of patients with CRVO was compared with the control subjects. Confidence interval was set at 95% with a P-value of < 0.05. RESULTS: MPV was significantly higher among hypertensive cases diagnosed with CRVO when compared with the hypertensive control group (8.059 ± 0.016, 7.442 ± 0.15 fL respectively; P < 0.001). The platelet count was lower in the control group, but the difference was not significant. The systolic blood pressure was significantly higher in the sample group. CONCLUSIONS: Our results demonstrated that MPV values were significantly higher in patients with CRVO, suggesting that increased MPV may contribute to the development of CRVO.

Retinal Vein Occlusion is Associated with Low Blood High-Density Lipoprotein Cholesterol: A Nationwide Cohort Study.

PURPOSE: To investigate association between the development of retinal vein occlusion (RVO) and blood high-density lipoprotein cholesterol (HDL-C). DESIGN: A retrospective, nationwide, population-based cohort study. METHODS: This study was set in the Republic of Korea and included 23,149,403 people ≥20 years of age who underwent the Korean National Health Screening Program examination between January 2009 and December 2012. Among them, the RVO group was composed of patients with an initial diagnosis of RVO made between 2009 and 2015 (n = 117,639). The earliest claim with an RVO diagnostic code was considered as the incident time. The predictive value of HDL-C level for RVO was analyzed using hazard ratios. The primary outcome measure was the incident cases of RVO. RESULTS: Subjects with RVO were generally older; had high body mass index, waist circumference, fasting blood glucose, blood pressure, total and low-density lipoprotein cholesterol, and triglyceride values, and low glomerular filtration rate and HDL-C values; and were more likely to experience diabetes mellitus and hypertension compared with the non-RVO group. The fully adjusted hazard ratio of RVO was 1.12 (95% confidence interval 1.10-1.14) in the lowest quartile of HDL-C versus in the highest quartile. The association between the development of RVO and HDL-C was higher those with a younger age, male sex, current smoking habit, diabetes mellitus, and hypercholesterolemia. In addition, we observed a significant synergistic effect of low HDL-C level with obesity and hypertension. CONCLUSION: This is the first nationwide population-based epidemiologic study evaluating the association between HDL-C level and the risk of RVO development. A significant association between low HDL-C and RVO development was found.

Elevation of serum oxidative stress in patients with retina vein occlusions.

PURPOSE: Retina vein occlusion (RVO) is a visual-threatening retinal disease that causes irreversible impaired quality of life. The contribution of oxidative stress behind clinical course of RVO was rarely investigated. The study aimed to measure the serum oxidative biomarker in patients with RVO to investigate further physical response. METHODS: We measured the serum levels of malondialdehyde (MDA), 8-hydroxy-2-deoxyguanosine (8OHdG), Sirutin 1 (SIRT1), peroxisome proliferator- activated receptor gamma (PPAR-r), Peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α), orkhead box protein O1 (FOXO1), orkhead box protein O3 (FOXO3), catalase, (SOD) and hydrogen peroxide (H2 O2 ) among 19 patients with cataract as control group and 36 patients with RVO, respectively. RESULTS: The mean MDA, 8OHdG and hydrogen peroxide in the serum were significantly higher in patients with RVO compared with the results in control group subjects. Whereas SIRT1, PPAR-r, PGC-1, FOXO1, FOXO3, catalase and SOD levels in serum were significantly decreased in patients with RVO compared with control group. CONCLUSION: We demonstrated that the serum level of MDA, 8OHdG and hydrogen peroxide is increased in patients with RVO. Among these, the elevation of MDA, 8OHdG and hydrogen peroxide suggests the increasing of serum oxidative stress in RVO patients. All enzymes related reactive oxygen species scavenge were decreased. Thus, focal RVO may increase systemic oxidative stress within serum.

Non-Occlusive Retinal Vascular Inflammation and Role of Red Blood Cell Deformability in Birdshot Chorioretinopathy.

Purpose: To investigate differences in red blood cell (RBC) deformability between birdshot chorioretinopathy (BCR) subjects and matched controls, and to postulate its relationship with lack of vascular occlusion in BCR. Methods: In a single center, prospective, non-randomized mechanistic study, blood samples were collected from eight healthy controls and nine BCR patients, and subjected to biochemical and hematological tests, as well as RBC indices assessment using dual-beam optical tweezers. Results: The mean age of the controls was 52.37 ± 10.70 years and BCR patients was 53.44 ± 12.39 years. Initial cell size (Io) for the controls was 8.48 ± 0.25 µm and 8.87 ± 0.31 µm for BCR RBCs (p = 0.014). The deformability index (DI) for the controls was 0.066 ± 0.02 and that for BCR RBCs was 0.063 ± 0.03 (p = 0.441). Conclusion: There was no statistically significant difference in DI between RBCs from BCR and healthy controls. This may explain the rare occurrence of retinal vascular occlusion despite the underlying vasculitic pathophysiology of BCR.

[Prevalence of Elevated Lipoprotein (a) Levels in Patients < 60 Years of Age with Retinal Vein Occlusion]. / Prävalenz erhöhter Lipoprotein(a)-Spiegel bei unter 60-jährigen Patienten mit venösen retinalen Gefäßverschlüssen.

BACKGROUND: The potential impact of elevated Lipoprotein (a) [Lp(a)] levels on retinal venous occlusive (RVO) diseases with regard to age and various risk factors has not been studied extensively. PATIENTS AND METHODS: In a retrospective case-control study, thrombophilia data of 106 young patients (< 60 years at the time of the RVO or a previous thromboembolic event) with RVO and 76 healthy subjects were evaluated. RESULTS: Elevated Lp(a) plasma levels were significantly more prevalent among RVO patients (29.2 %) than among controls (9.2 %; p = 0.0009). Lp(a) levels were found to be significantly (p = 0.012) different between patients and controls. Moreover, we found that an unusual personal or family history of thromboembolism was a strong predictor of elevated Lp(a) (p = 0.03). We observed a significant correlation between elevated Lp(a) and other coagulation disorders (p = 0.005). Multivariate analysis showed that elevated lipoprotein(a) levels (OR: 3.5; p = 0.003) were an independent risk factor for the development of RVO. CONCLUSIONS: Elevated plasma levels of Lp(a) are associated with the development of RVO. Selective screening of young patients and subjects with a personal or family history of thromboembolism may be helpful in identifying RVO patients with elevated Lp(a).

Thrombophilic and cardiovascular risk factors for retinal vein occlusion.

BACKGROUND: The role of thrombophilic and cardiovascular risk factors in different manifestations of retinal vein occlusion (RVO), i.e., central or branch RVO, and at different ages is still debated. AIMS: To evaluate the association between thrombophilic and cardiovascular risk factors and the risk of RVO (overall, separately for central and branch RVO, and at different ages). METHODS: Case-control study on 313 patients with a first objectively-confirmed RVO (216 central and 97 branch RVO) and 415 healthy individuals. RESULTS: Antithrombin, protein C or protein S deficiency (adjusted odds ratio [95%CI]: 15.60 [2.01-121]; p=0.009), hyperhomocysteinemia (HHCy; 3.22 [1.38-7.49]; p=0.007), high factor VIII (FVIII) levels (3.08 [1.20-7.89]; p=0.019), factor V Leiden (2.93 [0.97-8.86]; p=0.058) and the presence of at least one cardiovascular risk factor (1.79 [1.00-3.23]; p=0.050) were associated with an increased risk of branch RVO. The association was weaker for central RVO, and limited to HHCy (2.15 [1.09-4.24]; p=0.027) and high FVIII (1.99 [0.90-4.42]; p=0.091). For HHCy, high FVIII and cardiovascular risk factors the association with the risk of RVO was stronger at an age>50years (3.41[1.29-8.99], p=0.013; 2.57[1.00-6.68], p=0.050; and 2.03[1.16-3.56], p=0.013, respectively) than ≤50years (1.93[0.85-4.36], p=0.114; 1.67[0.54-5.12], p=0.371; and 1.22[0.73-2.03], p=0.454, respectively), whereas classic inherited thrombophilia (antithrombin, protein C or protein S deficiencies, factor V Leiden and prothrombin G20210A mutation) was slightly more prevalent at an age≤50years (1.62 [0.76-3.45], p=0.210) than >50years (1.11[0.44-2.79], p=0.833). CONCLUSIONS: Thrombophilic and cardiovascular risk factors are associated with RVO, particularly branch RVO. The risk of RVO associated with HHCy, high FVIII and cardiovascular risk factors is higher at an older age.

Retinal vein occlusion and paroxysmal nocturnal hemoglobinuria.

Paroxysmal nocturnal hemoglobinuria (PNH) is a rare disorder associated with increased risk for thrombosis and reduced life expectancy. Retinal vein occlusion (RVO) is a frequent cause of vision loss but its relationship with PNH has not been studied systematically. Patients followed up for RVO in our ophthalmology department were screened for the presence of a PNH clone in peripheral blood by means of flow cytometry. The presence of other well-documented risk factors for RVO was also analyzed. In a series of 110 patients (54 males, median age of 67) we found no evidence of PNH. Most patients (97/110) had cardiovascular risk factors and/or hyperhomocysteinemia (67/110). Inherited thrombophilias were rare (three confirmed cases). Therefore, PNH does not appear to play a role in the development of RVO. However, this finding does not necessarily apply to young patients and/or those with no conventional risk factors for RVO, due to the low number of patients in these subgroups in our population.

Observation and characterization of microvascular vasomotion using erythrocyte mediated ICG angiography (EM-ICG-A).

A clinical method for characterizing the state of micro-vasculature vasomotion is demonstrated, based on observing in capillaries the dynamics of autologously re-injected erythrocytes containing ICG dye. Since a manifestation of vasomotion is transient erythrocyte pausing, vasomotion state within a field of capillaries is characterized by an histogram plot of the number of paused erythrocytes as a function of pause duration during a fixed period of observation, then the ratio of long-pausing to short-pausing erythrocytes was calculated. The method was first applied to the posterior pole retinal vasculatures of anesthetized-monkey eyes, and normal vasomotion state during air-breathing was compared to the state induced by O2-breathing, known to cause mild arteriolar vasoconstriction in the mature eye. Subsequently, the effects of other antagonists to normal arteriolarvasotonia state (long-standing experimentally-induced ocular hypertension and branch-vein occlusion, as well as tissue edema) were similarly characterized and the results compared to those obtained during baseline air-breathing. The feasibility of applying the histogram characterization of vasomotion state to human eyes and skin was also preliminarily explored.

Platelet activation by ADP is increased in selected patients with anterior ischemic optic neuropathy or retinal vein occlusion.

To investigate whether adenosine diphosphate (ADP)-induced platelet hyperaggregability is associated with nonarteritic anterior ischemic optic neuropathy (NAION) or retinal vein occlusion (RVO). We retrospectively reviewed thrombophilia screening data of patients with NAION or RVO without a history of arterial hypertension, diabetes mellitus, hyperlipidemia, obesity, and cigarette abuse. Patients with a positive family history for thromboembolism were not excluded. Platelet aggregation (area under the curve, AUC) after induction of 0.5, 1.0, and 2.0 µmol of ADP was estimated in 25 NAION and RVO patients and compared with 25 healthy controls. We observed significantly greater platelet aggregation post 0.5 (P = 0.002) and 1.0 (P = 0.008) µmol of ADP among NAION and RVO patients compared with healthy controls. Platelet hyperaggregability was significantly more prevalent in patients than in controls (56% vs. 8%; P = 0.0006). Our results suggest that in NAION and RVO patients without a history of arterial hypertension, diabetes mellitus, hyperlipidemia, obesity, and cigarette abuse, platelets are significantly hyperreactive after induction of very low concentrations of ADP when compared with healthy individuals. This hyperreactivity is particularly evident in patients with a family history of thromboembolism.

Increased Fibrinogen to Albumin Ratio in Ischemic Retinal Vein Occlusions.

PURPOSE: To demonstrate the relationship between ischemia and plasma fibrinogen and serum albumin levels in cases of retinal vein occlusion (RVO). METHODS: This study included 44 patients with central RVO (CRVO), 68 patients with branch RVO (BRVO), and 54 age- and sex-matched controls, for a total of 166 subjects. All of the subjects underwent full ophthalmologic examinations and complete physical examinations, including a detailed medical history and blood count, and biochemical parameters. RESULTS: The mean fibrinogen to albumin ratios were 92.5 ± 36.1 for the patients with CRVO, 84.5 ± 31.5 for the patients with BRVO, and 68.4 ± 12.2 for the control group. Overall, the patients with CRVO and patients with BRVO with ischemia had higher fibrinogen to albumin ratios and higher fibrinogen levels. Moreover, significant positive correlations were found between ischemia and the fibrinogen to albumin ratio (r = 0.732, p = 0.001) and the fibrinogen level (r = 0.669, p = 0.001). CONCLUSIONS: The fibrinogen to albumin ratio is significantly associated with ischemic RVO. Instead of complicated and invasive methods, such as a retinal angiogram, the fibrinogen to albumin ratio could be a useful initial diagnostic test to predict ischemia in RVO.

Association of retinal vein occlusion, homocysteine, and the thrombophilic mutations in a Turkish population: A case-control study.

PURPOSE: To compare homocysteine and thrombophilic mutations for the methylenetetrahydrofolate reductase (MTHFR) C677T, factor V Leiden, and prothrombin G20210A between retinal vein occlusion (RVO) and healthy controls in a Turkish population. MATERIALS AND METHODS: Forty-nine subjects with RVO were compared for homocysteine status and the MTHFR C677T, prothrombin G20210A, and factor V Leiden mutations with those of 68 healthy controls. Then, the groups were subdivided into two subgroups according to age (less than 50 years old, equal to or more than 50 years old) and were further compared. RESULTS: Mean plasma level of homocysteine was similar, but the frequency of hyperhomocysteinemia was significantly higher in the RVO group when compared with the control group (22.5% and 8.8%, respectively, p = 0.037). The frequency of all thrombophilic mutations was similar between the groups (p > 0.05). The frequency of all thrombophilic mutations and homocysteine levels was also similar between age subgroups (p > 0.05). Only hyperhomocysteinemia was significantly different between subgroups (p = 0.037); the frequency of hyperhomocysteinemia was significantly different in RVO patients less than 50 years old (22.7%) from that in healthy controls less than 50 years old (11.1%). Two RVO patients (4.1%) with bilateral involvement had MTHFR C677T mutation. CONCLUSIONS: Screening for thrombophilic mutations such as MTHFR C677T, factor V Leiden, and prothrombin G20210A in RVO patients at all ages seems to be unnecessary and not cost-effective. However, thrombophilic disorders should be screened selectively, focusing on young individuals, especially with bilateral involvement, without additional cardiovascular risk factors, or a family history of thrombosis.