Intravitreal ranibizumab (Lucentis) for treatment of central retinal vein occlusion: a prospective study

Intravitreal bevacizumab versus ranibizumab: Effects on the vessels of the fellow non-treated eye

Purpose

To evaluate the effects of anti-vascular endothelial growth factors (anti-VEGF) on the vessels of the non-treated eyes following intravitreal injections.

Methods

In this prospective, non-randomized trial, a total of 38 patients were recruited. 21 patients received ranibizumab, and 17 patients received bevacizumab. Fundus photography was carried out at baseline immediately before injection and at 3 days, 7 days, and one month after the injections. Using image analysis software, measurements were summarized as the central retinal artery equivalent (CRAE) and central retinal vein equivalent.

Results

In non-treated eyes, CRAE decreased significantly from 153.23 ± 15.20 μm before injection to 148.77 ± 17.21 μm 3 days after intravitreal bevacizumab (P = 0.004). There was no significant difference in CRAE, between the pre-injection baseline, one week, and one month after intravitreal bevacizumab injection in non-treated eyes (P > 0.05). No significant difference was noted in CRAE in the non-treated eyes of the ranibizumab group at any post-injection visit (P = 0.1).

Conclusion

A significant transient narrowing effect of bevacizumab on retinal arterioles in the fellow non-treated eyes on the third day after intravitreal injection may show that plasma concentrations of these drugs are sufficient to spread the effect to the other eye.

One year results of intravitreal ranibizumab monotherapy for retinal angiomatous proliferation: a comparative analysis based on disease stages

Background

Retinal angiomatous proliferation (RAP) has been known as a variant of exudative age-related macular degeneration (AMD) with a unfavorable prognosis. To evaluate the effect of ranibizumab administered initially as three loading doses for patients with various stages of RAP.

Methods

A retrospective chart review of 40 patients (41 eyes) with RAP was conducted. The study divided patients into three groups of Group I (8 eyes in stage I), Group II (17eyes in stage II), and Group III (16 eyes in stage III). All patients received three initial monthly intravitreal injections (0.5 mg) of ranibizumab and were monitored monthly for 12 months. Reinjection of ranibizumab after three initial monthly doses was administered on as-needed basis. The main outcome measures were the change in the mean of best-corrected Snellen visual acuity (BCVA) and central macular thickness (CMT), and the total number of injections received during the 12 months.

Results

The mean change in BCVA at 12 months was-0.286,-0.165, and-0.151 (logMAR) in Group I, II, and III, respectively. CMT was also reduced by a mean of 32.72 ± 56.75, 57.45 ± 56.48 and 148.37 ± 98.59 μm. The mean number of injections in Group I was significant lower than those in Group II and III (P < 0.001, P < 0.001, and P = 0.15 for Group I versus Group II, Group I versus Group III, and Group II versus Group III, respectively).

Conclusions

The 12-month follow-up outcomes suggest that three consecutive loading doses of intravitreal ranibizumab is an effective treatment on early stage (stage I) of RAP. Patients in stage I showed a significantly lower recurrence rate than patients in later stages.

[Management of macular edema secondary to retinal vein occlusion]

BACKGROUND

In recent years, intravitreal injections have added to the treatment modalities available for macular edema (ME) secondary to retinal vein occlusion (RVO). This article aims to provide an update regarding the management of ME secondary to RVO.

METHODS

A work group met in order to analyze the literature available on Embase/PubMed, regarding treatments for venous occlusion that have received market approval and are reimbursed in France. In total, 33 articles were selected. Consensus within the group for recommendations was based on this data from the literature review and clinical experience and was reported in this article.

RESULTS

The management of ME secondary to branch retinal vein occlusion (BRVO) or central vein occlusion of the retina (CRVO) differs on a number of points. Methods of best practice were discussed separately for BRVO and CRVO, taking into account various ocular and associated parameters.

DISCUSSION

Ranibizumab and dexamethasone implant are the first-line treatments for visual impairment due to ME secondary to RVO. The choice of either of these drugs may take into account various ocular and extraocular parameters. A change of treatment to one or the other or to laser may also be considered during follow-up.

Intravitreal Bevacizumab in Central Retinal Vein Occlusion: 18-month Results of a Prospective Clinical Trial

Purpose.

To evaluate the long-term visual results in central retinal vein occlusion (CRVO) following repeated intravitreal injections of bevacizumab (IVB).

Methods.

Thirteen patients (aged 34 to 79 years) with a duration of CRVO of 2 weeks to 6 months (mean 2.5 months) had a best-corrected visual acuity (BCVA) 0.05 to 0.4 (mean 0.13) as determined by Early Treatment Diabetic Retinopathy Study (ETDRS) chart. Clinical examination was carried out at baseline and every 6 to 8 weeks. Intravitreal bevacizumab (1.25 mg) was given every 6 weeks during the first 6 months, and after that at the discretion of the attending physician.

Results.

In total, 96 IVB (average 7.4/patient) were given: 50 IVB during the first 6 months, 28 from 6 to 12 months, and 18 from 12 to 18 months. Average BCVA had improved 15 ETDRS letters at 3 months, 24 letters at 6 months, 24 letters at 12 months, and 18 letters at 18 months (p<0.05). Eight patients (62%) had gained >15 ETDRS letters at 12 months, and 7 subjects (54%) >15 ETDRS letters at 18 months. Foveal thickness decreased from 596 μm at baseline to 294 μm at 18 months (p<0.05) and mean IOP from 15.2 mmHg to 15.8 mmHg. No serious adverse events occurred.

Conclusions.

Following repeated IVB, there was a significant gain of BCVA during the follow-up of 18 months. To maintain visual gain, regular ophthalmologic examinations and repeated injections seem to be necessary as long as the disease is active.

Safety profiles of anti-VEGF drugs: bevacizumab, ranibizumab, aflibercept and ziv-aflibercept on human retinal pigment epithelium cells in culture

Purpose

To compare the safety profiles of antivascular endothelial growth factor (VEGF) drugs ranibizumab, bevacizumab, aflibercept and ziv-aflibercept on retinal pigment epithelium cells in culture.

Methods

Human retinal pigment epithelium cells (ARPE-19) were exposed for 24 h to four anti-VEGF drugs at 1/2×, 1×, 2× and 10× clinical concentrations. Cell viability and mitochondrial membrane potential assay were performed to evaluate early apoptotic changes and rate of overall cell death.

Results

Cell viability decreased at 10× concentrations in bevacizumab (82.38%, p=0.0001), aflibercept (82.68%, p=0.0002) and ziv-aflibercept (77.25%, p<0.0001), but not at lower concentrations. However, no changes were seen in cell viability in ranibizumab-treated cells at all concentrations including 10×. Mitochondrial membrane potential was slightly decreased in 10× ranibizumab-treated cells (89.61%, p=0.0006) and 2× and 10× aflibercept-treated cells (88.76%, 81.46%; p<0.01, respectively). A larger reduction in mitochondrial membrane potential was seen at 1×, 2× and 10× concentrations of bevacizumab (86.53%, 74.38%, 66.67%; p<0.01) and ziv-aflibercept (73.50%, 64.83% and 49.65% p<0.01) suggestive of early apoptosis at lower doses, including the clinical doses.

Conclusions

At clinical doses, neither ranibizumab nor aflibercept produced evidence of mitochondrial toxicity or cell death. However, bevacizumab and ziv-aflibercept showed mild mitochondrial toxicity at clinically relevant doses.

Late retinal neovascularization after central retinal vein occlusion: a case report and literature review

PURPOSE

To present the case of a 59-year-old man with central retinal vein occlusion with limited retinal ischemia who developed retinal neovascularization over a year after initial presentation.

METHODS

Retrospective case report.

RESULTS

On initial presentation, the patient had counting fingers vision in the affected eye and significant macular edema. After 4 intravitreal ranibizumab injections, his vision improved to 20/30. An intravenous fluorescein angiography performed at presentation and at a 4-month follow-up revealed limited retinal ischemia and no neovascularization. Over a year after his initial presentation, the patient returned with visual symptoms and was found to have subhyaloid hemorrhage and areas of retinal neovascularization.

CONCLUSION

Anterior and posterior segment neovascularization after central retinal vein occlusion has traditionally been thought to occur within a few months of the inciting event. However, the use of antivascular endothelial growth factor agents may alter the angiogenic processes within an eye after central retinal vein occlusion, potentially delaying the onset of neovascularization. This suggests the need for enhanced monitoring in this patient population.

Vitrectomy and panretinal photocoagulation reduces the occurrence of neovascular glaucoma in central retinal vein occlusion with vitreous hemorrhage

PURPOSE

The purpose of this study was to evaluate the best-corrected visual acuity and occurrence of neovascular glaucoma with vitrectomy (VT) and panretinal photocoagulation or without VT in central retinal vein occlusion (CRVO) associated with vitreous hemorrhage (VH).

METHODS

The charts from patients diagnosed as having CRVO with VH at Chang Gung Memorial Hospital (Taiwan) were reviewed. They were grouped based on whether they also underwent VT. The main outcome measurements were the best-corrected visual acuity and incidence of neovascular glaucoma.

RESULTS

There were 83 eyes that had CRVO with VH from 83 patients (VT group, 56 eyes; non-VT group, 27 eyes). There was no significant difference between the VT and non-VT groups in terms of age, gender, diabetes, hypertension, lens status, and follow-up period. The non-VT group had a better best-corrected visual acuity (P = 0.018) and less VH (P = 0.025) than the VT group at baseline; however, the VT group had a better best-corrected visual acuity at the end of the follow-up than the non-VT group (P < 0.001). Most importantly, there was a higher neovascular glaucoma development (37%) in the non-VT group compared with that (14.3%) in the VT group (P = 0.025).

CONCLUSION

The visual outcomes of CRVO with VH are unfavorable whether VT was performed. However, VT and panretinal photocoagulation improved visual acuity and reduced the incidence of neovascular glaucoma in CRVO with VH.

Prospective study of peripheral panretinal photocoagulation of areas of nonperfusion in central retinal vein occlusion

PURPOSE

To investigate the effect that panretinal photocoagulation to peripheral areas of retinal vascular nonperfusion has on the visual acuity and injection frequency of ranibizumab in eyes with previous central retinal vein occlusion.

METHODS

Patients enrolled in a prospective study of ranibizumab for central retinal vein occlusion were imaged with wide-field angiography using the Optos P200 system. Laser photocoagulation was carried out and the extent of laser photocoagulation was evaluated with repeat wide-field angiography. Injection of ranibizumab was based on an as needed strategy throughout the study. The injection frequency in the 6 months before laser was compared with a 6-month period starting 2 months after the laser photocoagulation. The visual acuity was measured by Early Treatment Diabetic Retinopathy Study protocol refraction at both the end of the 6-month follow-up period and at the time of laser photocoagulation.

RESULTS

There were 10 patients treated in this study with a mean number of 1,757 spots of laser photocoagulation in the peripheral retina. The injection frequency in the 6-month lead-in period was 3.4 and in the 6-month follow-up period was 3.1, a difference that was not significant (P = 0.26). The visual acuity at the time of laser photocoagulation was 54.2 letters (approximate Snellen equivalent of 20/80) and at the end of the observation period was 51.4 letters, a difference that was not significant (P = 0.33).

CONCLUSION

In this small study, laser photocoagulation to peripheral areas of nonperfusion as visualized by wide-field angiography did not result in either decreased injection frequency or improved visual acuity in eyes with central retinal vein occlusion treated with ranibizumab.

Therapeutic potential of intravitreal pharmacotherapy in retinal vein occlusion

Retinal vein occlusion (RVO) is the most common visually disabling disease affecting the retina after diabetic retinopathy. Although the disease entity has long been known, its management is still controversial. Macular edema is the main reason for decreased visual acuity (VA) in this retinal vascular disorder. Recently the vitreous cavity has increasingly been used as a reservoir of drugs for the direct treatment of macular edema through intravitreal injection route. The most widely injected drugs so far have been triamcinolone acetonide (TA) and bevacizumab. The objective of this review is to evaluate the evidence and discuss the rationale behind the recent suggestions that intravitreal pharmacotherapy by corticosteroids and anti-vascular endothelial growth factors may be useful in the treatment of retinal vein occlusion.

A prospective, randomised, multicenter trial for surgical treatment of central retinal vein occlusion: results of the Radial Optic Neurotomy for Central Vein Occlusion (ROVO) study group

BACKGROUND

To compare the surgical outcomes and evaluate the effectiveness of two treatments for central retinal vein occlusion (CRVO), radial optic neurotomy (RON) and intravitreal triamcinolone (IVT), in comparison to natural history.

METHODS

A prospective, placebo-controlled, randomised and multi-center study. Patients with CRVO were treated in three groups - with either RON, a single intravitreal injection of 4 mg triamcinolone acetonide, or a placebo treatment. The main outcome measures were change of VA (visual acuity) and proportion of eyes with a significant improvement (defined as > 3 lines logMAR scale) of VA from baseline to month 12.

RESULTS

Ninety patients were included. Due to insufficient data, seven were excluded. Forty-seven percent (n = 18) of patients treated with RON showed an increase in VA, in comparison to 10 % (n = 2) of placebo-treated patients, and 20 % (n = 5) of patients treated with IVT. Significantly more patients showed an improvement in VA following RON than in the placebo group (p = 0.009). Significantly more patients showed an improvement in VA following RON than in the IVT group (p = 0.034). No significant difference was found when directly comparing improvement in VA following IVT and placebo (p = 0.667) treatment.Significantly (p = 0.007) more patients in the placebo group (35 %, n = 7) showed a deterioration (defined as > 3 lines LogMAR scale) in VA than patients in the RON group (8 %, n = 3).

CONCLUSION

Our study showed that following treatment with RON, patients with CRVO display a significantly better long-term VA than untreated patients and patients treated with a single dose of IVT.

Ranibizumab: in macular oedema following retinal vein occlusion

Ranibizumab (Lucentis®), a recombinant humanized IgG(1) κ isotype monoclonal antibody fragment, is approved in the US for the treatment of macular oedema following retinal vein occlusion (RVO). It binds to the receptor-binding site of active forms of vascular endothelial growth factor-A, inhibiting its biological activity. In two large, well designed, phase III trials in patients with macular oedema following branch RVO (BRVO) or central RVO (CRVO), monthly intravitreal injections of ranibizumab 0.5 mg were associated with significantly greater improvement from baseline in mean best-corrected visual acuity letter score (measured on the Early Treatment Diabetic Retinopathy Study chart) in the study eye at 6 months (primary endpoint) than sham injections. Moreover, ranibizumab was significantly more effective than sham injections with regard to improvements in central foveal thickness at 6 months, as well as several other visual acuity measures. Ranibizumab was generally well tolerated in patients with macular oedema following CRVO or BRVO. Overall, the most common adverse events with ranibizumab were consistent with the adverse event profile previously reported in patients with age-related macular degeneration.

Retinal vein occlusion and macular edema - critical evaluation of the clinical value of ranibizumab

Retinal vein occlusions (RVOs) constitute the second most common cause of retinal vascular disease after diabetic retinopathy, with a prevalence of between 1% and 2% in persons older than 40 years of age. Despite the existence of numerous potential therapeutic options, none is entirely satisfactory, and many patients with RVO suffer irreversible visual loss. Fortunately however, the recent introduction of antivascular endothelial growth factor (VEGF) agents, such as ranibizumab (Lucentis^®, Genentech, South San Francisco, CA) and bevacizumab (Avastin^®, Genentech), offers a potentially new treatment approach for clinicians managing this disorder. The results of the BRAVO and CRUISE trials have provided the first definitive evidence for the efficacy and safety of ranibizumab in the treatment of RVO. As a result, ranibizumab has recently been approved by the US Food and Drug Administration for the treatment of RVO-associated macular edema. In this review, we provide a critical evaluation of clinical trial data for the safety and efficacy of ranibizumab, and address unresolved issues in the management of this disorder.

Economic considerations of macular edema therapies

PURPOSE

To relate costs and treatment benefits for diabetic macular edema (DME), branch retinal vein occlusion (BRVO), and central retinal vein occlusion (CRVO).

DESIGN

A model of resource use, outcomes, and cost-effectiveness and utility.

PARTICIPANTS

None.

METHODS

Results from published clinical trials (index studies) of laser, intravitreal corticosteroids, intravitreal anti-vascular endothelial growth factor (VEGF) agents, and vitrectomy trials were used to ascertain visual benefit and clinical protocols. Calculations followed from the costs of 1 year of treatment for each treatment modality and the visual benefits as ascertained.

MAIN OUTCOME MEASURES

Visual acuity (VA) saved, cost of therapy, cost per line saved, cost per line-year saved, and costs per quality-adjusted life years (QALYs).

RESULTS

The lines saved for DME (0.26-2.02), BRVO (0.74-4.92), and CRVO (1.2-3.75) yielded calculations of costs/line of saved VA for DME ($1329-$11,609), BRVO ($494-$13,039), and CRVO ($704-$7611); costs/line-year for DME ($60-$561), BRVO ($25-$754), and CRVO ($45-$473); and costs/QALY ($824 to $25,566).

CONCLUSIONS

Relative costs and benefits should be considered in perspective when applying and developing treatment strategies.

Effects of intravitreal triamcinolone acetonide on retinal gene expression in a rat model of central retinal vein occlusion

PURPOSE

The aim of this study was to investigate the effects of intravitreal triamcinolone acetonide on the alterations in retinal gene expression in a rat model of central retinal vein occlusion (CRVO).

METHODS

In one eye of adult Brown Norway rats (n = 77) CRVO was induced with laser photocoagulation of all retinal veins near to the optic disk after intraperitoneal injection of 0.2 ml of 10% sodium fluorescein. The gene expression was investigated using RT-PCR separately in the neural retina and retinal pigment epithelium (RPE) 1, 3, 7, and 14 days after CRVO induction. We analyzed the expression of factors that influence the development of vascular edema (VEGF-A, VEGF-B, PEDF), of channels implicated in retinal osmohomeostasis (Kir4.1, AQP4, AQP1), and of the pro-inflammatory factors IL-1ß and IL-6.

RESULTS

CRVO induced a rapid transient upregulation of Vegfa, a downregulation of Vegfb, and a delayed upregulation of Pedf in the neuroretina. In the neuroretina and retinal pigment epithelium, CRVO induced strong, transient downregulation of Kir4.1, Aqp4, and Aqp1, and striking rapid upregulation of Il1ß and Il6. Intravitreal triamcinolone reversed the downregulation of Kir4.1 and accelerated the normalization of the upregulated expression of Il1ß and Il6. The CRVO-induced transient upregulation of Vegfa was not influenced by the triamcinolone application.

CONCLUSIONS

Triamcinolone exerts anti-inflammatory effects in the ischemic retina by inhibitory effects on the gene expression of IL-1ß and IL-6, and may have neuroprotective effects via improvement of retinal potassium homeostasis.

Effects of intravitreal anti-vascular endothelial growth factor treatment on retinal vasculature in retinal vein occlusion as determined by ultra wide-field fluorescein angiography

PURPOSE

To investigate both peripheral and central retinal vascular changes after intravitreal anti-vascular endothelial growth factor (VEGF) therapy in the setting of acute retinal vein occlusion (RVO).

METHODS

Two patients with macular edema, one secondary to central RVO (CRVO) and one secondary to branch RVO (BRVO), underwent ultra wide-field (200°) photography and fluorescein angiography before and after a single intravitreal injection of an anti-VEGF agent. The patient with CRVO received an intravitreal injection of ranibizumab (0.5 mg/0.05 mL). The patient with BRVO received an intravitreal injection of bevacizumab (1.25 mg/0.05 mL). The eye with CRVO was reevaluated with ultra wide-field photography and fluorescein angiography at 7 days and 35 days after treatment. The eye with BRVO was reevaluated with ultra wide-field photography and fluorescein angiography at 30 days after treatment. Photographs and fluorescein angiographic results were analyzed for posttreatment changes in arteriovenous transit time, vessel caliber, vessel leakage, peripheral capillary nonperfusion, retinal hemorrhages, and nerve fiber layer infarcts.

RESULTS

In both eyes, there were no changes detected in the arteriovenous transit time or peripheral capillary nonperfusion after anti-VEGF therapy. A reduction in intraretinal hemorrhages and nerve fiber layer infarcts was observed at 7 days and 35 days after treatment in the patient with CRVO and at 30 days after treatment in the patient with BRVO. A decrease in vessel caliber was observed at 7 days after treatment in the patient with CRVO and at 30 days after treatment in the patient with BRVO. In the patient with CRVO, an increase in vessel caliber with a recurrence of vascular leakage was noted at the visit on Day 35.

CONCLUSION

Anti-VEGF therapy in the setting of RVO may initially decrease vessel caliber, retinal hemorrhages, and nerve fiber layer infarcts but does not appear to affect arteriovenous transit time or areas of peripheral capillary nonperfusion after a single treatment. The beneficial effects of anti-VEGF therapy in RVO appear transient, and multiple injections may be required for control of macular edema. Ultra wide-field angiography can be a useful tool in monitoring the treatment of RVO.

Hemodilution therapy using automated erythrocytapheresis in central retinal vein occlusion: results of a multicenter randomized controlled study

BACKGROUND

Central retinal vein occlusion (CRVO) leads to poor visual outcome in most eyes. Abnormal hemorheology was suspected to play a major role in its pathogenesis. CRVO treatment is still a matter of debate but several studies have pointed out the efficacy of isovolumic hemodilution. The aim of this study was to assess the feasibility and efficacy of hemodilution using automated erythrocytapheresis in recent-onset CRVO.

METHODS

In this prospective randomized controlled multicenter study, 61 consecutive CRVO patients were enrolled when they met the following criteria: CRVO lasting for 3 weeks or less, visual acuity ranging from 20/200 to 20/32, age between 18 and 85 years, no diabetes, no uncontrolled systemic hypertension, no antiplatelet or anticoagulant therapy, hematocrit higher than 38%, and signed informed consent. Patients were randomly assigned to the hemodilution group (n = 31) or to the control group (n = 30). Hemodilution therapy consisted of one session of erythrocytapheresis on outpatient basis, followed by additional session(s) for 6 weeks if needed. Target hematocrit was 35%. Follow-up was 12 months.

RESULTS

No statistical differences in age, associated risk factors, or CRVO characteristics were observed at baseline between both groups. Mean visual acuity was equivalent to 20/80 in the hemodilution group and to 20/63 in the control group (non-significant difference). In the treated group, mean number of hemodilution sessions was 3.3 (range, 1 to 6), and no major side-effects occurred. At the 12-month follow-up visit, 64.5% of the hemodilution group had visual acuity of 20/40 or better compared to 40% of the control group (p = .048). Visual change was a gain of 1.7 ETDRS line in the hemodilution group versus a loss of 2.3 lines in the control group (p = .007). There was less conversion into an ischemic form in the hemodilution group (11%) than in the control group (50%, p = .004). Mean final retinal thickness was 289 μm in the hemodilution group versus 401 μm in the control group (p = .068).

CONCLUSIONS

This multicenter controlled randomized study demonstrated that automated erythrocytapheresis is a safe and effective tool for performing hemodilution and confirmed that hemodilution therapy can improve the final prognosis of CRVO when applied in the early phase of the disease.

Anti-vascular endothelial growth factor for macular edema secondary to central retinal vein occlusion

BACKGROUND

Central retinal vein occlusion (CRVO) is a common retinal vascular disorder in which macular edema (ME) may develop, with a consequent reduction in visual acuity. The visual prognosis in CRVO-ME is poor in a substantial proportion of patients, especially those with the ischemic subtype, and until recently there has been no treatment of proven benefit. Macular grid laser treatment is ineffective, and whilst a few recent randomized controlled trials (RCTs) suggest short-term gains in visual acuity with intravitreal steroids for patients with non-ischemic CRVO-ME, there is no established treatment for ischemic CRVO-ME. Anti-vascular endothelial growth factor (anti-VEGF) agents have been used to treat ME resulting from a variety of causes and may represent a treatment option for CRVO-ME.

OBJECTIVES

To investigate the effectiveness and safety of intravitreal anti-VEGF agents in the treatment of CRVO-ME.

SEARCH STRATEGY

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (which contains the Cochrane Eyes and Vision Group Trials Register) (The Cochrane Library 2010, Issue 8), MEDLINE (January 1950 to August 2010), EMBASE (January 1980 to August 2010), Latin American and Caribbean Health Sciences Literature Database (LILACS) (January 1982 to August 2010), Cumulative Index to Nursing and Allied Health Literature (CINAHL) (January 1937 to August 2010), OpenSIGLE (January 1950 to August 2010), the metaRegister of Controlled Trials (mRCT) (www.controlled-trials.com) and ClinicalTrials.gov (www.clinicaltrials.gov). There were no language or date restrictions in the search for trials. The electronic databases were last searched on 10 August 2010.

SELECTION CRITERIA

We considered RCTs that compared intravitreal anti-VEGF agents of any dose or duration to sham injection or no treatment. We focused on studies that included individuals of any age or gender with unilateral or bilateral disease and a minimum of six months follow up. Secondarily, we considered non-randomized studies with the same criteria, but did not conduct a separate electronic search for these.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trial quality and extracted data.

MAIN RESULTS

We found two RCTs that met the inclusion criteria after independent and duplicate review of the search results. These RCTs utilized different anti-VEGF agents which cannot be assumed to be directly comparable. We, therefore, performed no meta-analysis. Evidence from these trials and from other non-randomized case series is summarized in this review.

AUTHORS' CONCLUSIONS

Ranibizumab and pegaptanib sodium have shown promise in the short-term treatment of non-ischemic CRVO-ME. However, effectiveness and safety data from larger RCTs with follow up beyond six months are not yet available. There are no RCT data on anti-VEGF agents in ischemic CRVO-ME. The use of anti-VEGF agents to treat this condition therefore remains experimental.

Retinal vein thrombosis: pathogenesis and management

Retinal vein occlusion (RVO) is the most common retinal vascular disease after diabetic retinopathy. Owing to its multifactorial nature, however, management of this condition remains a challenge. Of the two main types of RVO, branch retinal vein occlusion (BRVO) is more prevalent than central retinal vein occlusion (CRVO). Most patients develop the disease at an elderly age, and more than half of them have associated systemic disorders (e.g. hypertension, hyperlipidemia and/or diabetes mellitus). There is no evidence to suggest routine testing for heritable thrombophilias in patients with RVO. The main cause of the visual impairment is macular edema, while neovascularization of the retina and optic disc are the most serious complications leading to vitreous hemorrhage, retinal detachment and neovascular glaucoma. Macular grid laser photocoagulation is an effective treatment for macular edema in patients with BRVO and a visual acuity of 20/40 or less. Other treatment options for reducing the edema are intravitreal steroids, anti-VEGF drugs and vitrectomy. The recently introduced intravitreal application of steroids and anti-VEGF drugs may prove to be a better approach for improving visual acuity. Finally, scatter panretinal laserphotocoagulation can effectively treat neovascularization and its secondary complications.