Neovascular events in eyes with central retinal vein occlusion undergoing serial bevacizumab or ranibizumab intravitreal injections: a retrospective review

Sphingosine 1-phosphate, a potential target in neovascular retinal disease

Neovascular ocular diseases (such as age-related macular degeneration, diabetic retinopathy and retinal vein occlusion) are characterised by common pathological processes that contribute to disease progression. These include angiogenesis, oedema, inflammation, cell death and fibrosis. Currently available therapies target the effects of vascular endothelial growth factor (VEGF), the main mediator of pathological angiogenesis. Unfortunately, VEGF blockers are expensive biological therapeutics that necessitate frequent intravitreal administration and are associated with multiple adverse effects. Thus, alternative treatment options associated with fewer side effects are required for disease management. This review introduces sphingosine 1-phosphate (S1P) as a potential pharmacological target for the treatment of neovascular ocular pathologies. S1P is a sphingolipid mediator that controls cellular growth, differentiation, survival and death. S1P actions are mediated by five G protein-coupled receptors (S1P_1-5 receptors) which are abundantly expressed in all retinal and subretinal structures. The action of S1P on S1P₁ receptors can reduce angiogenesis, increase endothelium integrity, reduce photoreceptor apoptosis and protect the retina against neurodegeneration. Conversely, S1P₂ receptor signalling can increase neovascularisation, disrupt endothelial junctions, stimulate VEGF release, and induce retinal cell apoptosis and degeneration of neural retina. The aim of this review is to thoroughly discuss the role of S1P and its different receptor subtypes in angiogenesis, inflammation, apoptosis and fibrosis in order to determine which of these S1P-mediated processes may be targeted therapeutically.

Intravitreal ranibizumab versus aflibercept versus bevacizumab for macular oedema due to central retinal vein occlusion: the LEAVO non-inferiority three-arm RCT

BACKGROUND

Licensed ranibizumab (0.5 mg/0.05 ml Lucentis®; Novartis International AG, Basel, Switzerland) and aflibercept (2 mg/0.05 ml Eylea®; Bayer AG, Leverkusen, Germany) and unlicensed bevacizumab (1.25 mg/0.05 ml Avastin®; F. Hoffmann-La Roche AG, Basel, Switzerland) are used to treat macula oedema due to central retinal vein occlusion, but their relative clinical effectiveness, cost-effectiveness and impact on the UK NHS and Personal Social Services have never been directly compared over the typical disease treatment period.

OBJECTIVE

The objective was to compare the clinical effectiveness and cost-effectiveness of three intravitreal antivascular endothelial growth factor agents for the management of macula oedema due to central retinal vein occlusion.

DESIGN

This was a three-arm, double-masked, randomised controlled non-inferiority trial.

SETTING

The trial was set in 44 UK NHS ophthalmology departments, between 2014 and 2018.

PARTICIPANTS

A total of 463 patients with visual impairment due to macula oedema secondary to central retinal vein occlusion were included in the trial.

INTERVENTIONS

The participants were treated with repeated intravitreal injections of ranibizumab (n = 155), aflibercept (n = 154) or bevacizumab (n = 154).

MAIN OUTCOME MEASURES

The primary outcome was an increase in the best corrected visual acuity letter score from baseline to 100 weeks in the trial eye. The null hypothesis that aflibercept and bevacizumab are each inferior to ranibizumab was tested with a non-inferiority margin of -5 visual acuity letters over 100 weeks. Secondary outcomes included additional visual acuity, and imaging outcomes, Visual Function Questionnaire-25, EuroQol-5 Dimensions with and without a vision bolt-on, and drug side effects. Cost-effectiveness was estimated using treatment costs and Visual Function Questionnaire-Utility Index to measure quality-adjusted life-years.

RESULTS

The adjusted mean changes at 100 weeks in the best corrected visual acuity letter scores were as follows - ranibizumab, 12.5 letters (standard deviation 21.1 letters); aflibercept, 15.1 letters (standard deviation 18.7 letters); and bevacizumab, 9.8 letters (standard deviation 21.4 letters). Aflibercept was non-inferior to ranibizumab in the intention-to-treat population (adjusted mean best corrected visual acuity difference 2.23 letters, 95% confidence interval -2.17 to 6.63 letters; p = 0.0006), but not superior. The study was unable to demonstrate that bevacizumab was non-inferior to ranibizumab in the intention-to-treat population (adjusted mean best corrected visual acuity difference -1.73 letters, 95% confidence interval -6.12 to 2.67 letters; p = 0.071). A post hoc analysis was unable to demonstrate that bevacizumab was non-inferior to aflibercept in the intention-to-treat population (adjusted mean best corrected visual acuity difference was -3.96 letters, 95% confidence interval -8.34 to 0.42 letters; p = 0.32). All per-protocol population results were the same. Fewer injections were required with aflibercept (10.0) than with ranibizumab (11.8) (difference in means -1.8, 95% confidence interval -2.9 to -0.8). A post hoc analysis showed that more bevacizumab than aflibercept injections were required (difference in means 1.6, 95% confidence interval 0.5 to 2.7). There were no new safety concerns. The model- and trial-based cost-effectiveness analyses estimated that bevacizumab was the most cost-effective treatment at a threshold of £20,000-30,000 per quality-adjusted life-year.

LIMITATIONS

The comparison of aflibercept and bevacizumab was a post hoc analysis.

CONCLUSION

The study showed aflibercept to be non-inferior to ranibizumab. However, the possibility that bevacizumab is worse than ranibizumab and aflibercept by 5 visual acuity letters cannot be ruled out. Bevacizumab is an economically attractive treatment alternative and would lead to substantial cost savings to the NHS and other health-care systems. However, uncertainty about its relative effectiveness should be discussed comprehensively with patients, their representatives and funders before treatment is considered.

FUTURE WORK

To obtain extensive patient feedback and discuss with all stakeholders future bevacizumab NHS use.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN13623634.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 25, No. 38. See the NIHR Journals Library website for further project information.

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.

USE OF THE ISCHEMIC INDEX ON WIDEFIELD FLUORESCEIN ANGIOGRAPHY TO CHARACTERIZE A CENTRAL RETINAL VEIN OCCLUSION AS ISCHEMIC OR NONISCHEMIC

PURPOSE

To understand the relationship between baseline ischemic index (IsI) values on ultra-widefield fluorescein angiography and classification as ischemic central retinal vein occlusion (CRVO).

METHODS

Single-center retrospective cohort study of CRVO patients imaged using ultra-widefield fluorescein angiography from which IsI values were calculated. An ischemic CRVO was defined as those eyes with an afferent pupillary defect and counting fingers acuity or worse or neovascularization during the first year of follow-up. Logistic regression was performed to characterize the relation between the IsI and clinical outcomes.

RESULTS

Sixty eyes of 60 treatment-naive CRVO patients with baseline ultra-widefield fluorescein angiography and ≥1 year of follow-up were identified. Those with an IsI ≥35% were significantly more likely to have an ischemic CRVO during the first year of follow-up than those with an IsI <35% (83.3 vs. 13.9%, odds ratio 111, P < 0.0001). Baseline and final logarithm of the minimum angle of resolution acuity were worse in eyes with an IsI ≥35% (1.18 vs. 0.46, P < 0.001 and 1.26 vs. 0.45, P < 0.001, respectively) despite similar baseline and final central subfield thickness (P = 0.1-0.23).

CONCLUSION

A baseline IsI of ≥35% on ultra-widefield fluorescein angiography in eyes with treatment-naive CRVO was sensitive (90%) and specific (92.5%) for classification as an ischemic CRVO during the first year of follow-up.

Vitrectomy for macular edema due to retinal vein occlusion

Purpose: To determine the long-term outcomes of vitrectomy for the macular edema associated with a retinal vein occlusion (RVO).

Methods: This was a retrospective, consecutive, interventional case series. The intraoperative procedures included internal limiting membrane peeling, arteriovenous sheathotomy, radial optic neurotomy, and intravitreal triamcinolone acetonide injection at the end of the surgery. The main outcome was the best-corrected visual acuity (BCVA).

Results: Eight hundred and fifty-four eyes of 854 patients were studied. The eyes consisted of 602 with branch RVO (BRVO), 74 with hemi-central RVO (hemi-CRVO), 87 with nonischemic central retinal vein occlusion (CRVO), and 91 with ischemic CRVO. The mean follow-up period was 68.6 months with a range of 12 to 262 months. The mean BCVA was significantly improved at the final visit (P<0.0001 to 0.0016). The final BCVA improved in 74.4% of the BRVO eyes, in 58.1% of the hemi-CRVO eyes, in 57.4% of the nonischemic CRVO eyes, and in 51.6% of the ischemic CRVO eyes. Multiple regression analysis showed there was no significant relationship between the intraoperative combined procedures and the final BCVA.

Conclusions: The results indicate that the type of RVO is significantly associated with the final BCVA, and vitrectomy is a treatment option to improve and maintain BCVA for a long term.

Retinal Nonperfusion in the Posterior Pole Is Associated With Increased Risk of Neovascularization in Central Retinal Vein Occlusion

PURPOSE

To review the definition of ischaemic central retinal vein occlusion (CRVO) and stratify the risk of neovascular complication based on wider areas of visible retinal non-perfusion.

DESIGN

Retrospective consecutive case series and image analysis study.

METHODS

Setting: Moorfields Eye Hospital, London, United Kingdom.

STUDY POPULATION

Forty-two consecutive treatment-naïve eyes with CRVO imaged with ultra-widefield angiography with a minimum of 12 months follow-up.

OBSERVATION PROCEDURE

The spatial location and total area of retinal nonperfusion (measured in disc areas, DA) were determined using the validated concentric rings method. The area was corrected for projection distortion. The images were graded by 2 retinal physicians and average measurements used.

MAIN OUTCOME MEASURES

Development of neovascular complications.

RESULTS

The percentage of eyes developing new vessels increased from none in eyes with less than 10 DA of nonperfusion in total to 14.3% in eyes with 10-30 DA, 20.0% for 30-75 DA, and 80% risk with 75-150 DA of nonperfusion. From 13 (31.0%) eyes with a perfused posterior pole (an area encompassing a 5 disc diameter radius centered at the fovea) and more than 10 DA of nonperfusion isolated in the periphery (beyond the posterior pole), only 1 (7.7%) eye developed new vessels, odds ratio (OR) 0.12 [95% confidence interval (CI): 0.01, 1.03]. Comparatively, for 13 (31.0%) eyes with more than 10 DA of nonperfusion in the posterior pole, 11 (84.6%) developed new vessels, OR 74.25 [95% CI: 9.26, 595.30], P < .001.

CONCLUSION

With ultra-widefield angiography, we have ascertained that posterior pole nonperfusion of more than 10 DA remains the key risk factor for new vessel development compared to areas of nonperfusion confined to the periphery.

ISCHEMIC CENTRAL RETINAL VEIN OCCLUSION IN THE ANTI-VASCULAR ENDOTHELIAL GROWTH FACTOR ERA

PURPOSE

Anti-vascular endothelial growth factor therapy has improved the prognosis for patients with central retinal vein occlusion (CRVO). However, most studies published to date exclude ischemic CRVO. The purpose of this study was to describe the outcome in eyes with ischemic CRVO treated with anti-vascular endothelial growth factor therapy.

METHODS

Thirty-seven patients with ischemic CRVO from 3 centers were followed for at least 6 months. Data on patient demographic, vision status, and anti-vascular endothelial growth factor treatments were collected.

RESULTS

Average number of injections during the study period was 5. Younger age was associated with improved vision (P = 0.006). Patients with improved visual outcomes tended to have macular edema as the primary indication for treatment, whereas patients with worse outcomes tended to have neovascularization as the primary indication for treatment.

CONCLUSION

This study highlights significant variability in the use of anti-vascular endothelial growth factor therapy for ischemic CRVO and underscores that eyes with neovascularization tend to have worse visual outcomes.

Traumatic Branch Retinal Vein Occlusion With Retinal Neovascularization Following Inadvertent Retrobulbar Needle Perforation

Retrobulbar injection of anesthesia is one of the most common procedures performed for ophthalmic surgery. Complications are rare but can be potentially serious, including retrobulbar hemorrhage, brainstem anesthesia, and inadvertent globe perforation. This is the preliminary report describing branch retinal vein occlusion (BRVO) secondary to accidental retrobulbar needle laceration with subsequent preretinal neovascularization.

One-year outcome of bevacizumab therapy for chronic macular edema in central and branch retinal vein occlusions in real-world clinical practice in the UK

Background

The purpose of this study was to investigate the 12-month outcome of macular edema secondary to both chronic and new central and branch retinal vein occlusions treated with intravitreal bevacizumab in the real-life clinical setting in the UK.

Methods

Retrospective case notes analysis of consecutive patients with retinal vein occlusions treated with bevacizumab in 2010 to 2012. Outcome measures were visual acuity (measured with Snellen, converted into logMAR [logarithm of the minimum angle of resolution] for statistical calculation) and central retinal thickness at baseline, 4 weeks post-loading phase, and at 1 year.

Results

There were 56 and 100 patients with central and branch retinal vein occlusions, respectively, of whom 62% had chronic edema and received prior therapies and another 32% required additional laser treatments post-baseline bevacizumab. Baseline median visual acuity was 0.78 (interquartile range [IQR] 0.48–1.22) in the central group and 0.6 (IQR 0.3–0.78) in the branch group. In both groups, visual improvement was statistically significant from baseline compared to post-loading (P<0.001 and P=0.03, respectively), but was not significant by month 12 (P=0.058 and P=0.166, respectively); 30% improved by at least three lines and 44% improved by at least one line by month 12. Baseline median central retinal thickness was 449 μm (IQR 388–553) in the central group and 441 μm (IQR 357–501) in the branch group. However, the mean reduction in thickness was statistically significant at post-loading (P<0.001) and at the 12-month time point (P<0.001) for both groups. The average number of injections in 1 year was 4.2 in the central group and 3.3 in the branch group.

Conclusion

Our large real-world cohort results indicate that bevacizumab introduced to patients with either new or chronic edema due to retinal vein occlusion can result in resolution of edema and stabilization of vision in the first year.