Two-Year Efficacy of Ranibizumab Plus Laser-Induced Chorioretinal Anastomosis vs Ranibizumab Monotherapy for Central Retinal Vein Occlusion: A Randomized Clinical Trial

Benefits of a Laser Chorioretinal Anastomosis Plus Ranibizumab vs Ranibizumab Alone for Central Retinal Vein Occlusion: 4-Year Results

PURPOSE

To evaluate what clinical gains can be achieved over conventional treatment with ranibizumab alone for central retinal vein occlusion (CRVO) when causal pathology is additionally addressed successfully with a laser-induced chorio-retinal anastomosis (L-CRA).

DESIGN

Two-year extension of prospective, randomized controlled clinical trial.

METHODS

A total of 58 patients with macular edema secondary to CRVO were randomized 1:1 to receive either an L-CRA (n = 29) or sham procedure (n = 29) at baseline and then monthly intravitreal ranibizumab 0.5 mg. Outcomes (best corrected visual acuity [BCVA], central subfield thickness [CST], injection requirements) were monitored in the monthly pro re nata (PRN) ranibizumab phase from months 7 to 48.

RESULTS

Injection requirements for patients with a functioning L-CRA (24 of 29) during the monthly PRN period from 7 to 24 months were a mean (95% CI) of 2.18 (1.57, 2.78) injections compared to 7.07 (6.08, 8.06) (P < .0001) for control (ranibizumab alone). These decreased further over the next 2 years to 0.29 (0.14, 0.61) compared to 2.20 (1.68, 2.88) (P < .001) for the third year and 0.25 (0.11, 0.56) and 1.84 (1.34, 2.54) for the fourth year (P < .001). Mean BCVA was statistically different at all follow-up time points from month 7 through month 48 for the group with the functioning L-CRA compared to the control monotherapy group. This improved to 14.06 letters at month 48 (P = .009). There was no difference in CST between any of the groups over the 48 months of follow-up.

CONCLUSION

For CRVO patients, addressing causal pathology in addition to conventional therapy improves BCVA and reduces injection requirements.

Central retinal vein occlusion 36-month outcomes with anti-vascular endothelial growth factors: the Fight Retinal Blindness! registry

PURPOSE

To analyze the 3-year outcomes in a broad population of patients starting VEGF inhibitors for central retinal vein occlusion (CRVO) in routine clinical practice.

DESIGN

Observational database study.

PARTICIPANTS

Overall, 527 treatment-naïve CRVO eyes that commenced VEGF inhibitors between December 1, 2010 and 2018 were tracked in the Fight Retinal Blindness! registry.

METHODS

Longitudinal models were used to plot changes in visual acuity (VA) and central subfield thickness (CST).

MAIN OUTCOME MEASURES

Mean change in VA from baseline to 36 months, injections, visits, completion, switching, and suspensions of therapy > 180 days at the final review.

RESULTS

Overall (527 eyes) mean VA change (95% confidence interval [CI]) was + 10 (7, 12) letters, 37% had final VA ≥ 70 and 30% ≤ 35 letters, mean CST changed -306 μm. Completers (257/527, 49%) had mean 36-month changes in VA and CST of + 12 letters and -324 μm with a median of 18 injections at 26 visits. The adjusted mean VA change was similar to each VEGF inhibitor (mean, + 11.4 letters) despite a greater reduction in CST with aflibercept (-310 μm) versus ranibizumab (-258 μm) versus bevacizumab (-216 μm; P < 0.001). Eyes with baseline VA that was trial-eligible (19-73 letters; 356/527, 68%) gained 7 letters, very poor (< 19 letters; 129/527, 24%) gained 22 letters, or very good (> 73 letters; 42/527, 8%) lost 7 letters. Switching (160/527, 30%) was most often to aflibercept (79 eyes). By using suspensions and discontinuation reasons, we identified similar proportions had ceased therapy (154/527, 29%) and were still receiving it at 36 months (165/527, 31%). Only 62/527 eyes (12%) had resolution of macular edema without treatment for > 6 months.

CONCLUSIONS

Patients with CRVO that commenced VEGF inhibitors in routine care for whom follow-up was available had VA improvements of around 12 letters at 3 years, but with > 50% lost to follow-up, the VA outcome for the entire group was likely worse. The choice of VEGF inhibitor influenced CST but not VA outcomes. We estimated that around half of the eyes were still receiving injections after 36 months.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found after the references.

Long-term outcomes for patients treated for macular oedema secondary to retinal vein occlusion: a systematic review

This systematic review assessed the long-term outcomes for patients treated with intravitreal antivascular endothelial growth factor or dexamethasone for macular oedema (MO) secondary to retinal vein occlusion (RVO). Studies investigating patients of all ages with MO due to RVO only were included. The review was deliberately broad in scope, including comparative and non-comparative studies to ensure inclusion of real-world type evidence. Risk of bias was assessed. In total, 76 data sets were included (10 775 participants). Overall, mean best-corrected visual acuity (BCVA) improved from baseline to 5 years by 16.1 letters (p<0.01). BCVA improved from baseline in both central RVO (CRVO) and branch RVO (BRVOs) at 2 years, by 9.1 (p<0.01) (difference from baseline in CRVOs) and 9.1 (p<0.01) letters, respectively. At 5 years, BCVA improved from baseline in CRVOs by 15.6 letters and in BRVOs by 16.2; the difference between RVO types was not significant (p=0.18). Two studies had 5-year data for ranibizumab, and improvement was evident. There was no significant difference between outcomes in randomised controlled trials (RCTs) compared with non RCTs. These results suggest a benefit to receiving long-term intravitreal treatments for MO due to RVO.

Functional benefits of a chorioretinal anastomosis at 2 years in eyes with a central retinal vein occlusion treated with ranibizumab compared with ranibizumab monotherapy

Objective

To evaluate the functional benefits (best corrected visual acuity (BCVA), central subfield thickness, injection loads, central venous pressure (CVP)) of a laser-induced chorioretinal anastomosis (L-CRA) in patients with central retinal vein occlusion (CRVO) treated with ranibizumab compared with ranibizumab monotherapy.

Methods and Analysis

This is a post-hoc analysis of the 2-year randomised ranibizumab plus L-CRA for CRVO trial. Twenty-four patients (82.5%) developed a functioning or successful L-CRA; outcome effects were monitored in the monthly as-needed ranibizumab phase from months 7 to 24 and compared with the ranibizumab monotherapy group (n=29).

Results

From months 7 to 24, the mean (95% CI) injection load for the functioning L-CRA group was 2.18 (1.57 to 2.78) compared with 7.07 (6.08 to 8.06) for the control group (p<0.0001). The mean BCVA was averaged across all timepoints between the control and functioning L-CRA groups (average difference=11.46 (3.16 to 19.75) letters, p=0.01). At 2 years, there was an 82.5% reduction in the odds of high CVP (greater or equal to central retinal artery diastolic pressure) for those with a successful L-CRA compared with controls (p<0.0001).

Conclusion

For patients with CRVO, adding L-CRA as a causal-based treatment to conventional therapy reduced CVP and injection loads and offered improved BCVA.

Trial registration number ACTRN12612000004864.

Chorioretinal Anastomosis for Central Retinal Vein Occlusion: A Review of Its Development, Technique, Complications, and Role in Management

Treatments for central retinal vein occlusion (CRVO) have improved dramatically with the advent of intravitreal agents aimed at blocking the effects of the dominant hypoxia-induced upreglulated cytokine, which is vascular endothelial growth factor (VEGF). This cytokine breaks down the capillary endothelial barriers and is a major component of the macular edema in this condition. These treatments although impressive only address some of the sequelae of CRVO and have no effect on the underlying cause which is an obstruction to venous outflow leading to retinal blood flow stagnation and an elevation of the retinal central venous pressure (CVP). The creation of a laser-induced chorioretinal anastomosis (L-CRA) between the obstructed high pressure retinal venous circulation and the unobstructed low pressure choroidal venous circulation is a means addressing the causal pathology. The L-CRA will help lower the elevated CVP, which has been up until now an unaddressed component of the macular edema in this condition.This article reviews the preclinical and clinical development of the L-CRA and the results of the studies into its effect on the natural history of CRVO. It now can be used in combination with existing anti-VEGF treatments with the intravitreal agents addressing the component of the CRVO-induced macular edema due to the cytokine dysregulation, and the L-CRA addressing the component due to the elevated CVP and retinal venous stagnation. Improvements in laser technology have led to higher success rates in L-CRA creation and potential complications are now minimized and better controlled. The combination of L-CRA with intravitreal anti-VEGF agents offers the potential of a permanent cure with a significant reduction in the burden of therapy and improved visual outcomes in this condition.

Retinal function determined by flicker ERGs before and soon after intravitreal injection of anti-VEGF agents

Background

To evaluate the retinal function before and soon after an intravitreal injection of an anti-vascular endothelial growth factor (anti-VEGF) agents.

Methods

Seventy-nine eyes of 79 patients that were treated by an intravitreal injection of an anti-VEGF agent for age-related macular degeneration (AMD), diabetic macular edema (DME), or retinal vein occlusion (RVO) with macular edema (ME) were studied. The RETeval® system was used to record 28 Hz flicker electroretinograms (ERGs) from the injected and non-injected eyes before (Phase 1, P1), within 2 h after the injection (P2), and 2 to 24 h after the injection (P3). Patients were grouped by disease or by the injected agent and compared. The significance of the changes in the implicit times and amplitudes was determined by t tests.

Results

The amplitudes were not significantly different at the three phases. The implicit time of the injected eye was 31.2 ± 3.2 msec at P1, and it was not significantly different at P2 (31.7 ± 3.1 msec) but it was significantly longer at P3 (32.2 ± 3.3 msec, P < 0.01, ANOVA for both). The implicit time in the non-injected fellow eye was 30.5 ± 3.3 msec at P1, and it was significantly longer at P2 (31.1 ± 3.2 msec) and phase 3 (31.3 ± 3.4 msec, P < 0.01, ANOVA for both).

Conclusions

The results indicate that an intravitreal anti-VEGF injection will increase the implicit times not only in the injected eye but also in the non-injected eye soon after the intravitreal injection.