Bevacizumab for macular edema in central retinal vein occlusion: a prospective, randomized, double-masked clinical study

Retinal Vein Occlusion-Background Knowledge and Foreground Knowledge Prospects-A Review

Thrombosis of retinal veins is one of the most common retinal vascular diseases that may lead to vascular blindness. The latest epidemiological data leave no illusions that the burden on the healthcare system, as impacted by patients with this diagnosis, will increase worldwide. This obliges scientists to search for new therapeutic and diagnostic options. In the 21st century, there has been tremendous progress in retinal imaging techniques, which has facilitated a better understanding of the mechanisms related to the development of retinal vein occlusion (RVO) and its complications, and consequently has enabled the introduction of new treatment methods. Moreover, artificial intelligence (AI) is likely to assist in selecting the best treatment option for patients in the near future. The aim of this comprehensive review is to re-evaluate the old but still relevant data on the RVO and confront them with new studies. The paper will provide a detailed overview of diagnosis, current treatment, prevention, and future therapeutic possibilities regarding RVO, as well as clarifying the mechanism of macular edema in this disease entity.

A systematic review and meta-analysis of the effect of intravitreal VEGF inhibitors on cardiorenal outcomes

BACKGROUND

Vascular endothelial growth factor inhibitors (VEGFi) have transformed the treatment of many retinal diseases, including diabetic maculopathy. Increasing evidence supports systemic absorption of intravitreal VEGFi and development of significant cardiorenal side effects.

METHODS

Systematic review and meta-analysis (PROSPERO: CRD42020189037) of randomised controlled trials of intravitreal VEGFi treatments (bevacizumab, ranibizumab and aflibercept) for any eye disease. Outcomes of interest were cardiorenal side effects (hypertension, proteinuria, kidney function decline and heart failure). Fixed-effects meta-analyses were conducted where possible.

RESULTS

There were 78 trials (81 comparisons; 13 175 participants) that met criteria for inclusion: 47% were trials in diabetic eye disease. Hypertension (29 trials; 8570 participants) was equally common in VEGFi and control groups (7.3 versus 5.4%; RR 1.08 [0.91; 1.28]). New or worsening heart failure (10 trials; 3384 participants) had similar incidence in VEGFi and control groups (RR 1.03 [0.70; 1.51]). Proteinuria (5 trials; 1902 participants) was detectable in some VEGFi-treated participants (0.2%) but not controls (0.0%; RR 4.43 [0.49; 40.0]). Kidney function decline (9 trials; 3471 participants) was similar in VEGFi and control groups. In participants with diabetic eye disease, risk of all-cause mortality was higher in VEGFi-treated participants (RR 1.62 [1.04; 2.46]).

CONCLUSION

In trials of intravitreal VEGFi, we did not identify an increased risk of cardiorenal outcomes, though these outcomes were reported in only a minority of cases. There was an increased risk of death in VEGFi-treated participants with diabetic eye disease. Additional scrutiny of post-licensing observational data may improve recognition of safety concerns in VEGFi-treated patients.

Antivascular endothelial growth factor for macular oedema secondary to retinal vein occlusion: a systematic review and meta-analysis

Purpose

To evaluate the efficacy and safety of antivascular endothelial growth factor (anti-VEGF) agents in treating macular oedema due to retinal vein occlusion (RVO-ME).

Methods

Studies of randomised controlled trials were searched in PubMed, EMBASE, Cochrane databases and ClinicalTrials.gov registry. RevMan V.5.4 software and GRADE were used to synthesise the data and validate the evidence, respectively.

Results

Seventeen studies were included in this meta-analysis. The anti-VEGF agents showed significant better mean best-corrected visual acuity (BCVA) improvement, more patients with ≧15 Early Treatment in Diabetic Retinopathy Study (ETDRS) letters gained and fewer patients with ≧15 ETDRS letters lost, more effectiveness at reducing central retinal thickness (CRT) and improving the quality of life than sham and steroids both at 6 and 12 months. Compared with laser, the anti-VEGF agents showed significant BCVA improvement and more effectiveness at CRT both at 6 and 12 months. The proportion of eyes gaining ≧15 ETDRS letters was greater in the anti-VEGF group at 6 months. The anti-VEGF and other three groups reported similar levels of non-ocular serious adverse events (SAEs). The incidence of eye pain was significantly higher in the anti-VEGF group than in the sham group. There was a significant increase in the incidence of ocular AEs and conjunctival haemorrhage in the anti-VEGF group compared with the laser group. The incidence of elevated intraocular pressure and cataract was significantly higher in the steroid group than in the anti-VEGF group.

Conclusions

This meta-analysis suggested that treatment of ME secondary to RVO with anti-VEGF improves visual and anatomical outcomes compared with other treatments. Thus, anti-VEGF treatment is the first choice for treating patients with ME secondary to RVO.

Real-Life Efficacy of Bevacizumab Treatment for Macular Edema Secondary to Central Retinal Vein Occlusion according to Pro Re Nata or Treat-and-Extend Regimen in Eyes with or without Epiretinal Membrane

Purpose. To present real-life data of patients with macular edema (ME) secondary to central retinal vein occlusion (CRVO) treated with bevacizumab (BVZ); determine the possible influence of epiretinal membrane (ERM) on treatment efficacy; and compare treatment outcomes in a treat-and-extend regimen (TER) versus pro re nata (PRN). Methods. We carried out a retrospective analysis of 58 eyes (56 patients) with new-onset CRVO treated only with intravitreal bevacizumab according to TER or PRN. Outcome measures were best-corrected visual acuity (BCVA) and central retinal thickness (CRT) at baseline and 12 months after the first treatment, number of visits and injections, and presence of ERM confirmed by optical coherence tomography in the first 6 months. Results. At 12 months, the mean number of injections was 6.3 across all eyes, with significantly more injections given in TER ( $p<0.001$ ). Mean CRT improved from 627 μm to 359 μm ( $p<0.001$ ) in all eyes, with improvement noted in TER ( $p<0.001$ ), PRN ( $p<0.001$ ), ERM ( $p=0.003$ ), and non-ERM ( $p<0.001$ ) subgroups. The mean BCVA gain was +13.6 letters, and the mean BCVA improved from 0.81 to 0.54 LogMAR ( $p<0.001$ ) in all eyes. BCVA improvement from baseline was significant in TER ( $p<0.001$ ) and non-ERM ( $p<0.001$ ) but not in PRN ( $p=0.08$ ) or ERM ( $p=0.2$ ) subgroups. Seven eyes, all receiving PRN treatment, developed neovascularization. Conclusions. Intravitreal bevacizumab according to either PRN or TER resolved edema and stabilized vision in the first 12 months, with TER yielding significant visual improvement and avoiding neovascular complications. ERM had no influence on bevacizumab efficacy in reducing ME in CRVO during 12 months of treatment.

Central retinal thickness changes and risk of neovascular glaucoma after intravitreal bevacizumab injection in patients with central retinal vein occlusion

This retrospective study evaluated changes in the central retinal thickness (CRT) and the risk factors for neovascular glaucoma (NVG) after intravitreal bevacizumab injection under a pro re nata (PRN) regimen for macular oedema in 57 eyes with central retinal vein occlusion (CRVO). The clinical characteristics at the time of NVG diagnosis were assessed, and baseline and final clinical characteristics and mean CRT values at 1-, 3-, and 6-month follow-up evaluations were recorded. The incidence of NVG was 21.1%, with the neovascular group (12 eyes) showing poor baseline and final visual acuity, a higher incidence of baseline ischaemic-type CRVO and subretinal fluid, a higher mean CRT at the 1-month follow-up, and a higher number of intravitreal bevacizumab injections during the 6-month follow-up. Nine eyes with NVG (75%) showed a mean CRT < 300 μm at the time of diagnosis. An ischaemic CRVO and higher CRT at the 1-month follow-up were related to the development of NVG in the multivariate analysis. Thus, NVG development in CRVO patients treated with intravitreal bevacizumab injections was associated with an ischaemic CRVO and elevated CRT at the 1-month follow-up; PRN bevacizumab regimens based on CRT or control of macular oedema did not completely prevent NVG development.

Five-year outcomes after intravitreal bevacizumab of treatment-naive eyes with macular edema secondary to CRVO in routine clinical practice: Results of the Pan-American Collaborative Retina Study (PACORES) group

PURPOSE

The purpose of this study was to report the 5-year outcomes of treatment-naive eyes with cystoid macular edema secondary to central retinal vein occlusion treated with intravitreal bevacizumab in routine clinical practice.

METHODS

We conducted multicenter retrospective non-comparative case series of 102 eyes. The main outcome measured was the change in best-corrected visual acuity (BCVA) at 5 years. Secondary outcomes included the number of injections and the change in CMT at 5 years.

RESULTS

At 5 years, the mean BCVA improved from 1.22 ± 0.58 (Snellen 20/428) at baseline to 1.00 ± 0.68 logMAR (Snellen 20/200; p < 0.0001). At 5 years, 48 (47%) eyes had a gain of ≥ 3 lines, 41 (40.2%) eyes remained within 3 lines and 13 (12.7%) eyes had a loss of ≥ 3 lines of BCVA. The CMT improved from 740 ± 243 to 322 ± 179 µm (p < 0.0001). At 5 years, 59 (57.8%) eyes had a completely dry SD-OCT. Patients received a total of 10.6 ± 6.1 (range 6-27) injections. Baseline BCVA (p < 0.0001) and the duration of symptoms prior to initial anti-VEGF injection (p = 0.0274) were the only predictive factors for BCVA at 5 years.

CONCLUSIONS

After 5 years with an average of 10.6 injections, there was a mean gain of 0.22 logMAR. In addition, more eyes achieved a BCVA of ≥ 20/40, gained ≥ 3 lines and less patients had a BCVA ≤ 20/200. Eyes with a better baseline BCVA and a shorter duration of symptoms were more likely to achieve better BCVA at 5 years.

Risk of Death Associated With Intravitreal Anti-Vascular Endothelial Growth Factor Therapy: A Systematic Review and Meta-analysis

Importance

Although intravitreal anti-vascular endothelial growth factor (VEGF) treatment represents the first-line therapy for many retinal diseases, the issue of their systemic safety is debatable.

Objectives

To assess whether intravitreal anti-VEGF therapy might be associated with increased risk of mortality and which variables are associated with the increase.

Data Sources

PubMed, MEDLINE, and Embase databases, the Cochrane Library, and ClinicalTrials.gov were systematically searched from inception to May 6, 2019.

Study Selection

Randomized clinical trials comparing intravitreal anti-VEGF treatment with control groups and with follow-up of at least 6 months were selected.

Data Extraction and Synthesis

Data were independently collected by 2 investigators. Meta-analyses were conducted using the frequentist and Bayesian methods. For the frequentist approach, random- and fixed-effects models were used, with random-effects models considered the primary technique. Odds ratios (ORs) with 95% CIs were computed. For the bayesian approach, uninformative and informative priors were used. Odds ratios with 95% credible intervals (CrIs) were computed. Meta-regression analyses were based on random-effects models.

Main Outcomes and Measures

The primary outcome measure was the all-cause death rate. Secondary outcomes included meta-regression analyses on the following variables: type of drug, number of injections, follow-up time, diagnosis, and cardiovascular risk.

Results

Of 2336 studies identified, 34 unique studies with 8887 unique participants were included in the present meta-analysis. For the frequentist analysis, fixed- and random-effects models yielded similar estimates (ORs, 1.34 [95% CI, 0.95-2.07; P = .09] and 1.34 [95% CI, 0.89-2.01; P = .17], respectively). For the Bayesian approach, noninformative and informative priors yielded similar results (ORs, 1.34 [95% CrI, 0.79-2.34; 0.13 probability of OR≤1.00] and 1.40 [95% CrI, 0.82-2.32; 0.11 probability of OR≤1.00], respectively). Meta-regression analyses showed the following risk for 1 injection more: frequentist OR of 1.12 (95% CI, 1.04-1.22; P = .005) and Bayesian OR of 1.06 (95% CrI, 0.98-1.15; 0.06 probability of OR≤1.00).

Conclusions and Relevance

In this study, no difference was found in the mortality rate between intravitreal anti-VEGF treatment and control groups. Additional data seem warranted to determine whether the mortality rate is increased in patients receiving a greater number of injections.

PERIPHERAL ISCHEMIC RETINAL PHOTOCOAGULATION IN ADDITION TO INTRAVITREAL BEVACIZUMAB VERSUS INTRAVITREAL BEVACIZUMAB ALONE FOR THE TREATMENT OF MACULAR EDEMA SECONDARY TO CENTRAL RETINAL VEIN OCCLUSION: A Randomized Double-Masked Controlled Clinical Trial

PURPOSE

To investigate the effects of peripheral ischemic retinal photocoagulation in addition to intravitreal bevacizumab (IVB) in the treatment of macular edema due to ischemic central retinal vein occlusion.

METHODS

Forty-eight eyes of 48 treatment-naive patients were randomly selected and divided into 2 groups. Group A comprised 24 eyes that were treated with three consecutive monthly injections of IVB, and Group B comprised 24 eyes that were treated with IVB plus photocoagulation of the peripheral nonperfused retina. Further IVB injections were administered as needed in both groups. Monthly follow-up was conducted for 9 months after the first injection.

RESULTS

The data of 46 patients were analyzed. Best-corrected visual acuity changes from the fourth to eighth month follow-up in comparison with the baseline were significantly higher in Group B (P = 0.002-0.044-0.002-0.002-0.012). In addition, significant differences were observed in central macular thickness in Group B throughout the study period (all P < 0.001). Group B required less frequent IVB injections during the 9-month study period.

CONCLUSION

Photocoagulation of the retinal nonperfused area in patients with macular edema because of central retinal vein occlusion might amplify the beneficial effects of IVB on best-corrected visual acuity and central macular thickness and reduce the frequency of IVB injection.

Neovascular glaucoma in patients with central retinal vein occlusion: A real-life study in the anti-VEGF era

PURPOSE

To investigate the characteristics and treatment patterns of patients developing a neovascular event (NE) in the anterior chamber secondary to central retinal vein occlusion (CRVO) in an ordinary clinical setting.

METHODS

In this retrospective real-life study, data from 243 eyes presenting with CRVO during 2012-2013 were collected. Maximum follow-up was 5 years. All patients that developed NE were included in the analysis.

RESULTS

Of 243 eligible patients, 72 (30%) either presented with or developed NE during the follow-up. In these 72 patients, 23 (32%) eyes already had evidence of NE at baseline. Twenty-eight eyes (39%) developed NE after discontinuation of intravitreal therapy for macular oedema (ME). In this subgroup, the NE occurred 15.6 ± 13.8 months after the baseline visit and 4.1 ± 2.6 months after the last injection. Final best-corrected visual acuity was 8.6 Early Treatment Diabetic Retinopathy Study (ETDRS) letters in the group of patients presenting with NE compared to 8.1 ETDRS letters in the group that developed NE later on. Of the patients presenting with intraocular pressure (IOP) below 30 mmHg, 3/29 (10%) needed subsequent cyclodiode laser therapy compared to 35/43 (81%) patients with a baseline IOP above 30 mmHg (p < 0.001).

CONCLUSIONS

In a clinical setting, many patients show evidence of NE already at the first visit. A substantial part of patients develops NE a long time after presentation, commonly a few months after discontinuation of intravitreal therapy for ME. The visual prognosis is similar for patients presenting with NE and patients developing NE during follow-up. A high baseline IOP predicts the need for subsequent pressure-lowering procedures.

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.

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.

Use of Anti-VEGF Drugs in Retinal Vein Occlusions

Retinal vein occlusion (RVO) is one of the most prevalent causes of visual loss in the Western World. Its pathogenesis is still not completely known. Chronic macular edema and ischemia compromise the functional and anatomical status of the retina. Antivascular endothelial growth factor (anti-VEGF) injections have demonstrated better results than other previous options, including observation or laser therapy. This narrative review aims to analyze the current aspects related to these drugs.

Prospective evaluation of intravitreal bevacizumab for ischemic central retinal vein occlusion

Background

Although previous studies have evaluated the effect of anti-VEGF therapies for central retinal vein occlusion (CRVO) patients, the majority of previous studies have excluded or included a very small number of patients with ischemic CRVO (iCRVO). The aim of our study is to examine the effects of bevacizumab on macular edema secondary to ischemic central retinal vein occlusion, as well as the effects on central choroidal thickness and best-corrected visual acuity.

Methods

In this prospective, interventional case series, iCRVO was defined by the presence of ≥ 10 or more disc diameter areas of retinal nonperfusion by fluorescein angiography (FA) and by the presence of a b/a ratio less than 1.5 by full-field electroretinogram (ffERG). Nine eyes with iCRVO received monthly bevacizumab 0.5 mg injections at baseline and months 1 to 5 for a maximum of six injections. Main outcome measures were visual acuity (Snellen), central foveal thickness, and central choroidal thickness as measured by Spectral-Domain Optical Coherence Tomography (SD-OCT) at baseline and at 6 month following initial intravitreal bevacizumab injection. Pairwise t-tests and the Wilcoxon signed-rank test were conducted to compare the outcome measures.

Results

After intravitreal administration of bevacizumab, there was a significant reduction of central foveal thickness from 858 ± 311 μm at baseline to 243 ± 106 μm at the 6-month follow-up, as well as a significant reduction of central choroidal thickness from 282 ± 38 μm at baseline to 227 ± 56 μm at the 6-month follow-up (p = 0.0006, p = 0.0003 respectively). The visual acuity worsened from a median of 1.3 to 1.7 (p = 0.02).

Conclusion

In patients with iCRVO, intravitreal bevacizumab led to a reduction of central macular edema and central choroidal thickness, but a worsening of visual acuity. Intravitreal bevacizumab reduces macular edema but is not able to overcome the poor prognosis of iCRVO.

Intravitreal Medications for Retinal Vein Occlusion: Systematic Review and Meta-analysis

Purpose

To evaluate the outcomes of different intravitreal injections for the treatment of retinal vein occlusion including central retinal vein occlusion (CRVO) and branch retinal vein occlusion (BRVO).

Methods

PubMed, Cochrane, the metaRegister of ControlledTrials, and ClinicalTrials were searched for intravitreal anti-Vascular Endothelial Growth Factor (VEGF) and steroids with relevant keywords and date limitation of 2009-2018. Meta-analysis was performed on studies that met the defined inclusion criteria. Main outcomes were visual acuity (VA) and central macular thickness (CMT).

Results

Out of 681 studies, 36 articles (including 21 reporting CRVO and 15 dealing with BRVO) were selected for systematic review. All five intravitreal drugs including triamcinolone, dexamethasone, ranibizumab, bevacizumab, and aflibercept showed improvement of CMT and VA as compared to placebo or laser treatment. Six randomized controlled trials were selected for meta-analysis in RVO patients. The pooled mean difference of visual improvement between sham and ranibizumab was 12.7 Early Treatment for Diabetic Retinopathy Study (ETDRS) letters (95%CI: 11.00 to 13.2), and the pooled mean difference in CMT reduction was 221μm (95%CI: 153 to 284); both changes were significantly in favor of ranibizumab. The pooled mean difference of visual improvement between bevacizumab and triamcinolone was 5.3 ETDRS letters in favor of bevacizumab (95%CI: 16 μm to 17.5 μm). Triamcinolone led to 68.1 μm greater CMT reduction than bevacizumab (95%CI: 58 μm to 76 μm). However, none of these differences were statistically significant.

Conclusion

Treatment with anti-VEGF agents in RVO is superior to observation. No significant difference was seen between the eyes treated with bevacizumab or triamcinolone based on these results.

Anti-angiogenic Therapy for Retinal Disease

Recent breakthroughs in our understanding of the molecular pathophysiology of retinal vascular disease have allowed us to specifically target pathological angiogenesis while minimizing damage to the neurosensory retina. This is perhaps best exemplified by the development of therapies targeting the potent angiogenic growth factor and vascular permeability mediator, vascular endothelial growth factor (VEGF). Anti-VEGF therapies, initially introduced for the treatment of choroidal neovascularization in patients with age-related macular degeneration, have also had a dramatic impact on the management of retinal vascular disease and are currently an indispensable component for the treatment of macular edema in patients with diabetic eye disease and retinal vein occlusions. Emerging evidence supports expanding the use of therapies targeting VEGF for the treatment of retinal neovascularization in patients with diabetic retinopathy and retinopathy of prematurity. However, VEGF is among a growing list of angiogenic and vascular hyperpermeability factors that promote retinal vascular disease. Many of these mediators are expressed in response to stabilization of a single family of transcription factors, the hypoxia-inducible factors (HIFs), that regulate the expression of these angiogenic stimulators. Here we review the basic principles driving pathological angiogenesis and discuss the current state of retinal anti-angiogenic pharmacotherapy as well as future directions.

Effect of funding source on reporting bias in studies of intravitreal anti-vascular endothelial growth factor therapy for retinal vein occlusion

PURPOSE

To examine the relationship between industry funding and outcome reporting bias in high-quality studies investigating the use of intravitreal anti-vascular endothelial growth factor (VEGF) agents for patients with macular oedema secondary to branch or central retinal vein occlusion (RVO).

METHODS

This systematic review in PubMed and Ovid MEDLINE examined all randomized clinical trials and meta-analyses published in journals with impact factor of ≥2 that investigated effectiveness of intravitreal anti-VEGF therapy in patients with RVO. The main outcome measure was correspondence between statistical outcome and abstract conclusion wording.

RESULTS

Forty-five studies met inclusion criteria; 38 (84%) showed correspondence between outcome and abstract conclusion without difference between industry-funded and nonindustry-funded publications (p = 0.39) or between publications in journals with impact factor ≥3 versus <3 (p = 0.96).

CONCLUSION

In high-quality studies of intravitreal anti-VEGF therapy for RVO, neither industry funding nor journal impact factor affected the rate of outcome reporting bias.

Comparison of the efficacy and safety of drug therapies for macular edema secondary to central retinal vein occlusion

OBJECTIVES

To evaluate the efficacy and safety of anti-vascular endothelial growth factor (VEGF) agents and corticosteroids for the treatment of macular oedema (ME) secondary to central retinal vein occlusion (CRVO).

DESIGN

Systematic review and network meta-analysis.

PARTICIPANTS

Patients from previously reported randomised controlled trials (RCTs) comparing anti-VEGF and corticosteroids for the treatment of ME secondary to CRVO.

METHODS

Literature searches were conducted using PubMed, Medline, Embase, Cochrane Library and clinicaltrials.gov until March 2017. Therapeutic effects were estimated using the proportions of patients gaining/losing ≥15 letters, best-corrected visual acuity (BCVA) and central retinal thickness (CRT). Treatment safety was estimated using the proportions of adverse events, namely increased intraocular pressure (IOP), cataracts, vitreous haemorrhage (VH) and retinal tear. The software ADDIS (V.1.16.8) was used for analysis. Treatment effect and safety of different drugs could be ranked based on simulation.

RESULTS

Eleven RCTs comprising 2060 patients were identified. Regarding patients gaining ≥15 letters, aflibercept and ranibizumab were significantly more effective than sham/placebo at 6 months. Regarding patients losing ≥15 letters at 6 months, ranibizumab showed significant improvement compared with dexamethasone. Aflibercept, bevacizumab or ranibizumab showed greater improvements in BCVA than sham/placebo at 6 months. Intravitreal ranibizumab injection demonstrated greater CRT reduction than both sham and dexamethasone did. Dexamethasone had a higher risk of increased IOP than aflibercept and ranibizumab. Ranibizumab demonstrated a greater risk of cataracts than dexamethasone. Aflibercept and ranibizumab demonstrated low incidence of VH and retinal tear, respectively. Aflibercept had a slight advantage over ranibizumab as assessed by benefit-risk analysis.

CONCLUSIONS

Anti-VEGF agents have advantages in the treatment of ME secondary to CRVO. Aflibercept and ranibizumab showed marked BCVA improvement and CRT reduction. Aflibercept may have a slight advantage over ranibizumab. The results of this study can serve as a reference for clinicians to provide patient-tailored treatment.

PROSPERO REGISTRATION NUMBER

CRD42017064076.

Retinal oximetry and systemic arterial oxygen levels

PURPOSE

Continuous peripheral pulse oximetry for monitoring adequacy of oxygenation is probably the most important technological advance for patients' monitoring and safety in the last decades. Pulse oximetry has the disadvantage of measuring the peripheral circulation, and the only mean to measure oxygen content of the central circulation is by invasive technology. Determination of blood oxyhaemoglobin saturation in the retinal vessels of the eye can be achieved noninvasively through spectrophotometric retinal oximetry which provides access to the central nervous system circulation. The aim of the thesis was to determine whether retinal oximetry technique can be applied for estimation of the central nervous system circulation which until now has only been possible invasively. This was achieved by measuring oxyhaemoglobin saturation in three adult subject study groups: in people with central retinal vein occlusion (CRVO) to observe local tissue hypoxia, in patients with severe chronic obstructive pulmonary disease (COPD) on long-term oxygen therapy to observe systemic hypoxaemia and in healthy subjects during hyperoxic breathing to observe systemic hyperoxemia. In addition, the fourth study that is mentioned was performed to test whether retinal oximetry is feasible for neonates.

METHODS

Retinal oximetry in central retinal vein occlusion: Sixteen subjects with central retinal vein occlusion participated in the study. The oxyhaemoglobin saturation of the central retinal vein occlusion affected eye was compared with the fellow unaffected eye. Retinal oximetry in healthy people under hyperoxia: Thirty healthy subjects participated in the study, and the oxyhaemoglobin saturation of retinal arterioles and venules was compared between normoxic and hyperoxic breathing. Retinal oximetry in severe chronic obstructive pulmonary disease: Eleven patients with severe chronic obstructive pulmonary disease participated in the study. Retinal oximetry measurements were made with and without their daily supplemental oxygen therapy. Retinal arteriolar oxyhaemoglobin saturation when inspiring ambient air was compared with blood samples from the radial artery and finger pulse oximetry and healthy controls. The healthy control group was assembled from our database for comparison of oxyhaemoglobin saturation of retinal arterioles and venules during the ambient air breathing. The retinal oximeter is based on a conventional fundus camera and a specialized software. A beam splitter coupled with two high-resolution digital cameras allows for simultaneous acquisition of retinal images at separative wavelengths for calculation of oxyhaemoglobin saturation. In addition, retinal images of 28 full-term healthy neonates were obtained with scanning laser ophthalmoscope combined with modified Oxymap analysis software for calculation of the optical density ratio and vessel diameter RESULTS: Retinal oximetry in central retinal vein occlusion: Mean retinal venous oxyhaemoglobin saturation was 31 ± 12% in CRVO eyes and 52 ± 11% in unaffected fellow eyes (mean ± SD, n = 14, p < 0.0001). The arteriovenous oxygen difference (AV-difference) was 63 ± 11% in CRVO eyes and 43 ± 7% in fellow eyes (p < 0.0001). The variability of retinal venous oxyhaemoglobin saturation was considerable within and between eyes affected by CRVO. There was no difference in oxyhaemoglobin saturation of retinal arterioles between the CRVO eyes and the unaffected eyes (p = 0.49). Retinal oximetry in healthy people under hyperoxia: During hyperoxic breathing, the oxyhaemoglobin saturation in retinal arterioles increased to 94.5 ± 3.8% as compared with 92.0 ± 3.7% at baseline (n = 30, p < 0.0001). In venules, the mean oxyhaemoglobin saturation increased to 76.2 ± 8.0% from 51.3 ± 5.6% (p < 0.0001) at baseline. The AV-difference was markedly lower during hyperoxic breathing as compared with the normoxic breathing (18.3 ± 9.0% versus 40.7 ± 5.7%, p < 0.0001). Retinal oximetry in severe chronic obstructive pulmonary disease: During ambient air breathing, chronic obstructive pulmonary disease subjects had significantly lower oxyhaemoglobin saturation than healthy controls in both retinal arterioles (87.2 ± 4.9% versus 93.4 ± 4.3%, p = 0.02, n = 11) and venules (45.0 ± 10.3% versus 55.2 ± 5.5%, p = 0.01) but the AV-difference was not markedly different (p = 0.17). Administration of their prescribed oxygen therapy significantly increased the oxyhaemoglobin saturation in retinal arterioles (87.2 ± 4.9% to 89.5 ± 6.0%, p = 0.02) but not in venules (45.0 ± 10.3% to 46.7 ± 12.8%, p = 0.3). Retinal oximetry values were slightly lower than finger pulse oximetry (mean percentage points difference = -3.1 ± 5.5) and radial artery blood values (-5.0 ± 5.4). Retinal oximetry study in neonates: The modified version of the retinal oximetry instrument estimated the optical density ratio in retinal arterioles to be 0.256 ± 0.041 that was significantly different from the 0.421 ± 0.089 in venules (n = 28, p < 0.001, paired t-test). The vascular diameter of retinal arterioles was markedly narrower than of venules (14.1 ± 2.7 and 19.7 ± 3.7 pixels, p < 0.001).

CONCLUSION

The results of this thesis indicate that spectrophotometric retinal oximetry is sensitive to both local and systemic changes in oxyhaemoglobin saturation. Retinal oxyhaemoglobin saturation values are slightly lower than radial artery blood sample and finger pulse oximetry values. The discrepancies between the different modalities are expected to derive from countercurrent exchange between central retinal artery and vein within the optic nerve but calibration issues cannot be excluded as contributing to this difference. Despite these differences, the findings indicate the potential of retinal oximetry for noninvasive real-time measurements of oxyhaemoglobin saturation in central nervous system vessels. Following calibration upgrade and technological improvement, verification retinal oximetry may potentially be applied to critically ill and anaesthesia care patients. The study on combined scanning laser ophthalmoscope and retinal oximetry supports the feasibility of the technique for oximetry analysis in newly born babies.

Comparative efficacy of bevacizumab, ranibizumab, and aflibercept for treatment of macular edema secondary to retinal vein occlusion: a systematic review and network meta-analysis

INTRODUCTION

Anti-vascular endothelial growth factor (VEGF) therapy has become the most commonly used treatment for macular edema secondary to retinal vein occlusion (RVO). Although its superior efficacy as compared to other interventions has been proven, there is a lack of evidence for relative efficacy among anti-VEGF drugs. Areas covered: This work systematically reviewed and compared the efficacy of intravitreal bevacizumab, ranibizumab, and aflibercept for treating macular edema due to RVO. PubMed, EMBASE, and the Cochrane Library were searched from their inception until October 2017. Eleven randomized controlled trials (18 articles; 1830 adult patients) were identified. The proportion of patients who gained at least 15 letters in best-corrected visual acuity (BCVA), mean change from baseline in BCVA, and mean change from baseline in central macular thickness (CMT) were reported and these efficacy outcomes at 6 months were analyzed in network meta-analysis. Expert commentary: Apparently, bevacizumab, ranibizumab, and aflibercept were significantly superior to sham injection in terms of BCVA improvement and CMT reduction and had good safety profiles. However, there were no statistically significant differences in any outcomes among anti-VEGF drugs. In selecting an anti-VEGF drug for individual patients, other factors including affordability, drug availability, and patient characteristics should be considered.

INTRAVITREAL INJECTIONS OF ZIV-AFLIBERCEPT FOR THE TREATMENT OF A PATIENT WITH MACULAR EDEMA SECONDARY TO BRANCH RETINAL VEIN OCCLUSION

PURPOSE

To describe the visual, tomographic, and electroretinographic findings in a patient with macular edema secondary to branch retinal vein occlusion who was submitted to three consecutive intravitreal injections of ziv-aflibercept.

METHODS

The patient underwent a complete ophthalmic examination, as well as optical coherence tomography and full-field electroretinography at baseline and 90 days after the first injection.

RESULTS

The best-corrected visual acuity improved from 20/400 to 20/40, and the central retinal thickness decreased from 791 μm to 198 μm after three consecutive intravitreal injections of ziv-aflibercept. Full-field electroretinography showed an increase in cone amplitude and decrease in rod amplitude. No adverse side effects were observed after injections.

CONCLUSION

Intravitreal injections of ziv-aflibercept showed both effectiveness and safety in the treatment of a patient with macular edema secondary to branch retinal vein occlusion. The observed anatomic (by ophthalmic examination, optical coherence tomography) and functional (best-corrected visual acuity, full-field electroretinography) improvements and lack of serious adverse side effects demonstrates the potential of intravitreal injections of ziv-aflibercept for the treatment of macular edema secondary to branch retinal vein occlusion.

Intravitreal Injection of Anti-vascular Endothelial Growth Factor Agents for Ocular Vascular Diseases: Clinical Practice Guideline

PURPOSE

To provide the clinical recommendations for the administration of intravitreal anti-vascular endothelial growth factor (VEGF) drugs especially bavacizumab for ocular vascular diseases including diabetic macular edema, neovascular age-related macular degeneration, myopic choroidal neovascularization, retinal vein occlusion and central serous chorioretinopathy.

METHODS

Twenty clinical questions were developed by the guideline technical committee. Relevant websites and databases were searched to find out the pertinent clinical practice guidelines to answer the questions. The technical committee provided possible answers (scenarios) according to the available evidences for each question. All scenarios along with their levels of evidence and the supported articles were sent to the experts for external review. If the experts did not agree on any of the scenarios for one particular clinical question, the technical committee reviewed all scenarios and their pertinent evidences and made the necessary decision. After that, the experts were asked to score them again. All confirmed scenarios were gathered as the final recommendations.

RESULTS

All the experts agreed on at least one of the scenarios. The technical committee extracted the agreed scenario for each clinical question as the final recommendation. Finally, 56 recommendations were developed for the procedure of intravitreal anti-VEGF injection and their applications in the management of ocular vascular diseases.

CONCLUSION

The implementation of this guideline can standardize the management of the common ocular vascular diseases by intravitreal injection of anti-VEGF agents. It can lead to better policy-making and evidence-based clinical decision by ophthalmologists and optimal evidence based eye care for patients.

The short-term efficacy of intravitreal ranibizumab, aflibercept and dexamethasone implant in the treatment of macular edema due to non-ischemic central retinal vein occlusion

PURPOSE

To assess and compare the efficacy over 6 months of intravitreal ranibizumab (IR), aflibercept (IA) and dexamethasone implant (IDI) in eyes with macular edema (ME) secondary to non-ischemic central retinal vein occlusion (CRVO).

METHODS

This is a retrospective single-center study. Patients who received pro re nata treatment of IR 0.5 mg, IA 2 mg or IDI 0.7 mg (as Group 1, Group 2, and Group 3, respectively) for the treatment of ME due to non-ischemic CRVO were included in the study. Efficacy outcomes were considered as the changes in mean best-corrected visual acuity (BCVA) and central macular thickness (CMT) from baseline over 6 months.

RESULTS

Eighteen patients (Group 1) received IR, 16 patients received (Group 2) IA, and 24 patients (Group 3) received IDI. The mean numbers of injections were 2.56 ± 1.0, 2.68 ± 0.9, and 1.62 ± 0.5 in Group 1, 2, and 3, respectively (p = 0.000). In Groups 1 and 2, the mean BCVA values increased significantly after the treatment (p < 0.001). However, in Group 3, no increase in mean BCVA was statistically significant in any month (p = 0.061). The proportion of eyes gaining at least three lines in BCVA was 33.3% in Group 1, 43.8% in Group 2, and 33.3% in Group 3 (p = 0.762). In all groups, significant improvements were observed in CMT after treatment (p < 0.001). At month 6, the mean changes in CMT were - 162.7 ± 186.5 µm in Group 1, - 310.1 ± 345.9 µm in Group 2, and - 193.8 ± 228.3 µm in Group 3, with no significant difference among groups (p = 0.474). Cataract formation and IOP increase were higher in the IDI group, but the differences were not statistically significant (p = 0.054 and p = 0.392, respectively).

CONCLUSIONS

IR and IA may be preferred treatment for ME due to non-ischemic CRVO as visual improvement remains the primary ophthalmological objective. The most important advantages of IDI are its effect on CMT and the need for fewer injections. The increase in IOP and the formation of cataract may be observed more in IDI-treated eyes.

Aflibercept Versus Bevacizumab and/or Ranibizumab for Recurrent Macular Edema Secondary to Central Retinal Vein Occlusion

PURPOSE

To compare functional and anatomic outcomes of treatment with intravitreal aflibercept versus bevacizumab and/or ranibizumab in patients with recurrent macular edema (ME) secondary to central retinal vein occlusion (CRVO).

METHODS

Retrospective, comparative case series of patients with recurrent ME in the setting of CRVO. Patients with recurrent ME received treatment with aflibercept (Group 1, G1) or bevacizumab and/or ranibizumab (Group 2, G2). Primary outcome measures were best-corrected visual acuity (BCVA) and central foveal thickness (CFT).

RESULTS

Of the 20 eyes (20 patients) with recurrent ME included in the study, 9 received aflibercept (G1) and 11 received bevacizumab and/or ranibizumab (G2). Median BCVA at recurrence of ME and at most recent follow-up was 20/60 (G1) and 20/80 (G2) and 20/40 (G1) and 20/50 (G2, P > 0.05 for all comparisons), respectively. Median CFT at recurrence of ME and at most recent follow-up was 492 μm (G1) and 448 μm (G2) and 291 μm (G1) and 295 μm (G2, P > 0.05 for all comparisons), respectively. Complete resolution of ME for at least 4 months was found in 78% (G1) and 55% (G2) of patients with a median injection free interval of 11 (G1) and 13 (G2) months (P > 0.05).

CONCLUSIONS

In patients with recurrent ME secondary to CRVO, there was improvement in BCVA and CFT in all groups, although patients treated with aflibercept showed a trend toward better anatomical outcomes decreased need for recurrent injections.

Intravitreal bevacizumab injections versus dexamethasone implant for treatment-naïve retinal vein occlusion related macular edema

Purpose

To compare the short-term effects of three monthly intravitreal bevacizumab (IVB) injections to single dexamethasone (DEX) implantation in treatment-naïve patients with cystoid macular edema (CME) secondary to branch (BRVO) and central retinal vein occlusion (CRVO).

Design

A retrospective single-center study.

Subjects

A total of 135 eyes of 135 patients with BRVO (n=83) and CRVO (n=52).

Methods

Changes in clinical parameters were recorded before treatment and at the first and third month after commencement of IVB (n=121) and DEX (n=14).

Main outcome measures

Central retinal thickness (CRT), intraocular pressure (IOP), and best-corrected visual acuity (BCVA).

Results

The baseline parameters were comparable between IVB and DEX groups. After the first month, CRT decreased by 131.3±42.9 μm in IVB and by 266.9±48.3 μm in DEX (mean ± SEM; p=0.047). IOP change was –0.29±0.39 mmHg in IVB and +3.70±2.34 mmHg in DEX (p=0.005). IOP elevation to ≥25 mmHg and ≥5 mmHg from the baseline was observed in two of the DEX- and in none of the IVB-treated eyes (p=0.010). After the third month, no differences regarding CRT and IOP were observed between the treatment modalities. Moreover, BCVA gain was comparable between IVB (0.37±0.05 logarithm of minimum angle of resolution [logMAR] units) and DEX (0.33±0.30 logMAR units) groups.

Conclusion

DEX was associated with faster resolution of CME, but had greater probability for short-term IOP elevation when compared to IVB. After the third month, treatments were comparably effective. Anatomical outcomes and adverse drug reactions of IVB versus DEX should be considered case specifically in patients having CME secondary to BRVO/CRVO.

Comparison of treatment response to intravitreal injection of triamcinolone, bevacizumab and combined form in patients with central retinal vein occlusion: A randomized clinical trial

BACKGROUND

Central retinal vein occlusion (CRVO), is the second-most common disorder after diabetic retinopathy that threatens the vision related to retinal vessels. One of the main reasons of vision loss is CRVO in acute and chronic forms.

OBJECTIVE

The aim of this study was to investigate the response to intravitreal injection of triamcinolone, bevacizumab, and a combined form in patients with CRVO.

METHODS

This study was a double-blinded randomized clinical trial conducted on patients with CRVO who were referred to the ophthalmology clinic of Urmia Imam Khomeini Hospital from May 2015 to May 2016. In total, ninety patients were divided into three groups using random numbers table. The first group received intravitreal triamcinolone acetonide (IVT) for treatment of macular edema due to CRVO, the second group received intravitreal bevacizumab (IVB) and the third group received a combination of IVT and IVB. The best corrected visual acuity (BCVA) and central macular thickness (CMT) were recorded and analyzed using optical coherence tomography system.

RESULTS

In this study a total of 90 eyes were studied, 41 case (45.55%) were male and 49 cases (54.44%) were female. The mean age of patients was 68.41±8.32 years. The mean score of final visual acuity was 0.293±0.11 in the IVT group, 0.25±0.10 in the IVB group and 0.48±0.15 in the IVB+IVT group. The differences between groups considering final visual acuity was significant (p<0.001). The mean thickness of final macular was 383.33±97.70 micrometer in IVT group, 386.33±136.79 micrometers in IVB group and 307.33±110.79 micrometers in IVT+IVB group which were significant (p=0.014).

CONCLUSION

Using a combination of bevacizumab and triamcinolone in the treatment of central retinal vein occlusion compared with using each of them separately, had a better result and can be used as a solution in this disease.

TRIAL REGISTRATION

The trial was registered at the Thai Registry of Clinical Trials (http://www.clinicaltrials.in.th) with the TCTR ID: TCTR20170612005.

FUNDING

The authors received no financial support for the research, authorship, and/or publication of this article.

Switch of Intravitreal Therapy for Macular Edema Secondary to Retinal Vein Occlusion from Anti-VEGF to Dexamethasone Implant and Vice Versa

PURPOSE

To evaluate the anatomical and functional outcome of intravitreal dexamethasone implant for macular edema secondary to central (C) or branch (B) retinal vein occlusion (RVO) in patients with persistent macular edema (ME) refractory to intravitreal antivascular endothelial growth factor (VEGF) treatment compared to treatment naïve patients and to dexamethasone-refractory eyes switched to anti-VEGF.

METHODS

Retrospective, observational study including 30 eyes previously treated with anti-VEGF (8 CRVO, 22 BRVO, mean age 69 ± 10 yrs), compared to 11 treatment naïve eyes (6 CRVO, 5 BRVO, 73 ± 11 yrs) and compared to dexamethasone nonresponders (2 CRVO, 4 BRVO, 69 ± 12). Outcome parameters were change in best-corrected visual acuity (BCVA) and central foveal thickness (CFT) measured by spectral-domain optical coherence tomography.

RESULTS

Mean BCVA improvement after switch to dexamethasone implant was 4 letters (p = 0.08), and treatment naïve eyes gained 10 letters (p = 0.66), while we noted no change in eyes after switch to anti-VEGF (p = 0.74). Median CFT decrease was most pronounced in treatment naïve patients (-437 μm, p = 0.002) compared to anti-VEGF refractory eyes (-170 μm, p = 0.003) and dexamethasone-refractory eyes (-157, p = 0.31).

CONCLUSIONS

Dexamethasone significantly reduced ME secondary to RVO refractory to anti-VEGF. Functional gain was limited compared to treatment naïve eyes, probably due to worse BCVA and CFT at baseline in treatment naïve eyes.

Anti-Vascular Endothelial Growth Factor Agents in the Treatment of Retinal Disease: From Bench to Bedside

The association of retinal hypoxia with retinal neovascularization has been recognized for decades, causing Michaelson to postulate in 1948 that a factor secreted by hypoxic retina was involved. The isolation of vascular endothelial growth factor (VEGF), characterization of its angiogenic activity, and demonstration that its expression was increased in hypoxic tissue made it a prime candidate. Intraocular levels of VEGF are elevated in patients with retinal or iris neovascularization, and VEGF-specific antagonists markedly suppress retinal neovascularization in mice and primates with ischemic retinopathy. Vascular endothelial growth factor antagonists also suppress choroidal neovascularization, and transgenic expression of VEGF in the retina of mice causes subretinal neovascularization. Clinical trials using a VEGF antagonist that blocks all isoforms of VEGF-A in patients with neovascular age-related macular degeneration (nAMD) demonstrated dramatic benefit. Similar results have been obtained with 2 other VEGF antagonists. Retinal hypoxia also contributes to diabetic macular edema (DME), and because of the absence of good animal models, small clinical trials were used to test the role of VEGF. The results clearly implicated VEGF as a major contributor to DME and have been confirmed by several large multicenter trials. A similar strategy demonstrated that VEGF is a major contributor to macular edema resulting from retinal vein occlusion, also confirmed in multicenter trials. Secondary outcomes in these large clinical trials have shown that VEGF inhibition improves retinal hemorrhages, retinal vessel closure, and progression of nonproliferative diabetic retinopathy. Anti-VEGF agents also provide therapeutic benefits in proliferative diabetic retinopathy. Thus, the development of VEGF antagonists has revolutionized the treatment of nAMD, diabetic retinopathy, and other ischemic retinopathies, but in many patients, the upregulation of VEGF is prolonged. Although the molecular signaling by which hypoxia and some other insults lead to upregulation of VEGF has been elucidated, it has not yet led to a treatment that reliably reduces the production of VEGF, necessitating continued neutralization by repeated intraocular injections of VEGF antagonists in many patients. The next horizon in the evolution of anti-VEGF therapy is the development of longer-acting agents or delivery platforms that provide sustained neutralization with fewer injections.

RETINAL VEIN OCCLUSIONS, FROM BASICS TO THE LATEST TREATMENT

PURPOSE

To review the pathophysiology, diagnosis, and updated treatments of retinal vein occlusions (RVOs).

METHODS

A review of the literature was performed, focusing on the epidemiology, pathophysiology, diagnosis, and treatments (including both medical and surgical treatments) of RVO. Based on this review, a comprehensive overview was provided regarding the topic of RVO and focused on recent treatment updates.

RESULTS

Retinal vein occlusions have an age- and sex-standardized prevalence of 5.20 per 1,000 for any RVO, 4.42 per 1,000 for branch RVO, 0.80 per 1,000 for central RVO. Worldwide, an estimated 16.4 million adults are affected by RVOs, with 2.5 million affected by central RVO and 13.9 million affected by branch RVO. Retinal vein occlusion is recognized as an important cause of blindness and the diagnostic approaches and treatment options for RVO are reviewed and reported. The current treatment options including medical treatments (bevacizumab, ranibizumab, aflibercept, triamcinolone, and dexamethasone implants) and surgical alternatives were reviewed and reported with summaries on the corresponding strength of evidence.

CONCLUSION

Despite the understanding of this disease entity, challenges persist in the long-term treatment of RVO-related complications and visual loss. This review provided a detailed summary on the rationality and efficacy of recently developed treatment regimes and evaluated the potential benefit of combination therapy.

Central Retinal Vein Occlusion: A Review of Current Evidence-based Treatment Options

A central retinal vein occlusion (CRVO) can induce an ischemic and hypoxic state with resulting sequelae of macular edema and neovascularization. Many treatment options have been studied. Our review aims to investigate the safety and efficacy of the multiple treatment options of CRVO. A PubMed and Cochrane literature search was performed. Well-controlled randomized clinical trials that demonstrated strong level 1 evidence-based on the rating scale developed by the British Centre for Evidence-Based Medicine were included. Seven clinical trials met inclusion criteria to be included in this review. These included studies that investigated the safety and efficacy of retinal photocoagulation (1 study), intravitreal steroid treatment (2 studies), and antivascular endothelial growth factor treatment (4 studies) for the treatment of CRVO. In addition, studies evaluating surgical treatment options for CRVO were also included. Many treatment modalities have been demonstrated to be safe and efficacious in the treatment of CRVO. These treatment options offer therapeutic benefits for patients and clinically superior visual acuity and perhaps the quality of life after suffering from a CRVO.

Vitamin D Deficiency in Patients with Central Retinal Vein Occlusion: A Case Control Study

PURPOSE

Central retinal vein occlusion (CRVO) has been shown to occur more often in winter/spring season. We aimed to evaluate if patients with CRVO have more vitamin D deficiency compared to matched controls.

METHODS

Prospective match controlled study of 72 patients with CRVO and 144 matched controls. All new CRVO cases presenting at St. Erik Eye Hospital, Stockholm, Sweden during the study period were approached to participate. Statistics Sweden provided randomly selected controls matched for age, gender, and season. The first 18 cases of CRVO and 36 controls for each of the four seasons were included and blood was drawn for 25-OH vitamin D analysis (25(OH)D).

RESULTS

About half of the patients (51.4%) in the CRVO group had vitamin D deficiency [25(OH)D < 50 nmol/l] as compared to 39.3% in the control group [odds ratio 1.64, 95% confidence interval (CI) 0.91-2.94]. The mean concentrations of serum 25(OH)D were 55.3 nmol/l (95% CI 48.4-62.2) in the study group and 59.8 nmol/l (95% CI 55.4-64.2) in the control group (p = 0.28). In stratified analysis, the CRVO patients under 75 years had significantly lower 25(OH)D levels than the matched controls (47.8 nmol/l vs. 59.0 nmol/l, p = 0.02).

CONCLUSIONS

Vitamin D deficiency is common in patients with CRVO. No significant differences in vitamin deficiency or 25(OH)D levels were found in comparison to the control group. However, the CRVO patients under 75 years had significantly lower 25(OH)D levels as compared to the control group.

Update in the Management of Macular Edema Following Retinal Vein Occlusions

Retinal vein occlusion (RVO) is a common retinal vascular disease classified according to the anatomical location of the occlusion in central (CRVO) or branch (BRVO) retinal vein occlusion. RVO is an important cause of visual loss worldwide and frequently results in visual impairment and ocular complications. Major causes of vision loss in BRVO and CRVO include macular edema (ME), capillary non-perfusion, and neovascularization, causing glaucoma, vitreous hemorrhage and/or tractional retinal detachment.[1-4] Macular edema is the leading cause of decreased central visual acuity in RVO.[5] Recently, there was a paradigm shift in the treatment of ME due to RVO with the advent of new pharmacotherapy treatment strategies and combination therapies. This paper reviews the current thinking and discusses the evidence behind the emerging treatment options for ME following RVO, including laser photocoagulation, intravitreal anti-vascular endothelial growth factor (VEGF), intravitreal corticosteroid-based pharmacotherapies, and surgical management.

Predictors of short-term outcomes related to central subfield foveal thickness after intravitreal bevacizumab for macular edema due to central retinal vein occlusion

AIM

To investigate the predictive factors for short-term effects of intravitreal bevacizumab injections on central subfield foveal thickness (CSFT) in patients with macular edema (ME) secondary to central retinal vein occlusion (CRVO).

METHODS

This was a retrospective study in 60 eyes treated with intravitreal bevacizumab injections for ME due to CRVO. Follow-up was three months. The Early Treatment Diabetic Retinopathy Study (ETDRS) score and CSFT measured by spectral-domain optical coherence tomography (SD-OCT) were used to observe the changes in best-corrected visual acuity (BCVA). Baseline BCVA, CSFT, age, CRVO duration and the presence of cystoid macular edema (CME) or subretinal fluid (SRF) were analyzed as potential predictive factors of the effects of intravitreal bevacizumab injections.

RESULTS

BCVA improved from 0.9 logMAR at baseline to 0.6 logMAR at 3mo, which was associated with a significant reduction in CSFT from 721 µm to 392 µm 3mo after injection. About 50% of CME cases and more than 90% of SRF cases responded to treatment with a complete resolution at 3mo. Age (P=0.036) and low baseline CSFT (P=0.037) were associated with a good 3-month prognosis. Patients >60 years old achieved better CME resolution (P=0.031) and lower CSFT at 3mo (305 µm vs 474 µm, P=0.003).

CONCLUSION

Intravitreal bevacizumab significantly improved visual acuity and CSFT in patients with CRVO after 3mo. Older age and lower baseline CSFT were good predictors of short-term CSFT outcomes. The retinal thickness response to bevacizumab might depend on the resolution of CME rather than SRF.

[Retinal vein occlusion: Therapy of retinal vein occlusion]

Treatment of retinal vein occlusion can be systemic or local. Therapeutic strategies include improved blood supply, treatment of the vision-reducing macular edema by intravitreal injection of inhibitors of vascular endothelial growth factors (VEGF) or corticosteroids and laser photocoagulation for neovascular complications. As long as head-to-head studies comparing steroids and VEGF inhibitors have not been published, none of the available intravitreally injected substances can be given priority. Well-known side effects of intravitreal steroids are cataract formation and ocular hypertension whereas VEGF inhibitors need to be frequently injected. Although therapy for retinal vein occlusion is protracted, initial long-term data indicate that treatment can be terminated in at least half of the patients . Finally, a treatment recommendation according to the current state of data is presented.