Combination therapy with intravitreal bevacizumab and macular grid and scatter laser photocoagulation in patients with macular edema secondary to branch retinal vein occlusion

Real-World Outcomes in Patients with Branch Retinal Vein Occlusion- (BRVO-) Related Macular Edema Treated with Anti-VEGF Injections Alone versus Anti-VEGF Injections Combined with Focal Laser

The purpose of this study was to assess outcomes in a real-world nonclinical trial setting of antivascular endothelial growth factor (VEGF) injections alone vs. focal laser combined with anti-VEGF injections in patients with branch retinal vein occlusion- (BRVO-) related macular edema (ME). This study included 88 BRVO with ME patients who were treated over three years at both a tertiary referral center in the Birmingham metropolitan area and satellites in rural Alabama. One group received only anti-VEGF injections (n = 56); the other group received both anti-VEGF injections and focal laser (n = 32). The following outcome measures were evaluated: initial and final visual acuities (VA), initial central subfield thickness (CST) on OCT, number of injections, number of lasers, percentage of patients with a gain of 3 lines of VA, percentage of patients with VA better than or equal to 20/40, and percentage of patients with VA worse than or equal to 20/200. We found that there was no difference in initial VA (p=0.913) or CST (p=0.961) between the two groups. The injection only group required a median of 7 injections, while the combination group required a median of 4 injections, but this was not a statistically significant difference (p=0.117). There was no difference in final VA (p=0.414) or any of the other visual outcomes between the two groups. In conclusion, focal laser did not decrease the number of injections required or improve the VA in BRVO-related ME. Although visual outcomes were similar in both groups, focal laser does not appear to be of additional benefit in BRVO-related ME in the anti-VEGF era.

Protective effects of hydrogen gas in a rat model of branch retinal vein occlusion via decreasing VEGF-α expression

Background

Oxidative stress (OS) is an essential factor in the pathogenesis of branch retinal vein occlusion (BRVO). Studies have demonstrated the role of hydrogen gas in the regulation of OS. This study was designed to evaluate the efficacy of hydrogen gas on the BRVO rat model.

Methods

Twenty-four BRVO rats were randomly divided into two groups: the hydrogen gas (H) group (42% H₂, 21% O₂, 37% N₂) and the model (M) group (21% O₂, 79% N₂). Rats in the H group inhaled hydrogen gas for 8 h every day up to 30 d post-occlusion. Twelve age-matched healthy rats served as the control (C) group. Retinal function and morphology were detected at 1, 7, 14 and 30 d post-occlusion. Furthermore, the expression of vascular endothelial growth factor (VEGF-α) was detected by immunofluorescent staining.

Results

Full-field electroretinography (ffERG) revealed that the amplitude of the b-wave (dark-adaptation 3.0 response), the amplitude of the OPs2 wave and the light-adapted flicker response in the H group were all higher than those in the M group at 7 d post-occlusion (all p < 0.05). The reopen time of occlusive retinal vessels in the H group was 2.235 ± 1.128 d, which was shorter than that in the M group (4.234 ± 2.236 d, p < 0.05). The rats in the H group had a thinner IPL + GCL + NFL and an increased total retina compared with those in the M group at 3 d post-occlusion (p < 0.05), while the rats in the H group had a thicker INL, IPL + GCL + NFL and total retina compared with those at 7, 14 and 30 d post-occlusion (p < 0.05). Moreover, the flow velocity of ear vein blood was increased in the H group compared with that in the M group (p < 0.05). The expression of VEGF-α in the H group was dramatically decreased compared with that in the M group at 1, 7 and 14 d post-occlusion (p < 0.05), while the expression kept in similar level at 30 d post-occlusion (p > 0.05).

Conclusions

Our findings demonstrate that inhalation of hydrogen gas could alleviate retinal oedema, shorten reopen time and improve retinal function, and the potential mechanism might be related to a decrease in VEGF-α expression.

Early-scatter laser photocoagulation promotes the formation of collateral vessels in branch retinal vein occlusion

PURPOSE

To investigate the effect of early-scatter laser photocoagulation on the formation of collateral vessels in branch retinal vein occlusion.

METHODS

The medical records of 40 cases (40 patients) of branch retinal vein occlusion with macular edema were retrospectively reviewed. Of them, 23 patients were treated with intravitreal bevacizumab injection and 17 patients underwent intravitreal bevacizumab injection with additional laser treatment. Early-scatter laser photocoagulation was applied for capillary non-perfusion areas, regardless of retinal neovascularization. Collateral vessel presence, recurrence rate of macular edema, and number of intravitreal bevacizumab injections were compared between the groups.

RESULTS

During the follow-up period, collateral vessel formation was noted in 10/23 eyes (43.5%) in the intravitreal bevacizumab injection group and 15/17 eyes (88.2%) in the laser combined treatment group (p = 0.004). The recurrence rate of macular edema was lower in the laser combined treatment group (29.4%) than in the intravitreal bevacizumab injection group (65.2%); this difference was statistically significant (p = 0.025). The average numbers of intravitreal bevacizumab injections were 3.57 ± 3.23 in the intravitreal bevacizumab group and 2.14 ± 2.26 in the laser combined treatment group (p = 0.044).

CONCLUSION

Early-scatter laser photocoagulation promotes collateral vessel formation; the presence of collateral vessels seemed to affect the course of macular edema in branch retinal vein occlusion. Combined early-scatter laser photocoagulation treatment after intravitreal bevacizumab injection lowered the recurrence rate of macular edema and number of intravitreal bevacizumab injections in the cases of branch retinal vein occlusion.

Bevacizumab versus bevacizumab and macular grid photocoagulation for macular edema in eyes with non-ischemic branch retinal vein occlusion: results from a prospective randomized study

BACKGROUND

The objective of the study was the investigation of the effects of intravitreal bevacizumab (BEV) with or without additional macular grid laser photocoagulation (GRID) for macular edema (ME) secondary to branch retinal vein occlusion (BRVO).

METHODS

Prospective, randomized, monocentric study. Thirty-two patients were included. Initially, all eyes in both groups received three monthly injections of BEV, followed by additional injections if re-treatment criteria were met. In the BEV + GRID group, photocoagulation was performed 2 weeks after the first BEV injection and laser re-treatment was allowed. The follow-up was 38 weeks. Main outcome measures were best-corrected visual acuity (BCVA) and central retinal thickness (CRT). Changes of foveal avascular zone (FAZ) and of retinal ischemia, as well as the number of injections were also evaluated.

RESULTS

Sixteen eyes were randomized into each group. At baseline, BCVA was similar in both groups (BEV + GRID: 20/71; BEV: 20/60; P = 0.51). At 38 weeks, BCVA significantly improved in the two groups (BEV + GRID gain of 9 ± 11.2 letters and 16.25 ± 10.08 letters in the BEV) with no difference between them (P < 0.06). With regard to anatomical findings, initial CRT in BEV + GRID was 496.2 μm ± 138.4 μm and 538.9 μm ± 156.9 μm in BEV (P < 0.1697). At 38 weeks, CRT decreased in both groups significantly, 98.2 μm in the BEV + GRID (P = 0.02) and 141.7 μm in the BEV group (P = 0.01), with no significant difference between groups (P < 0.17). The area of FAZ a significantly increased in both groups (41% (P = 0.04) in BEV + GRID; 35% (P = 0.03) in BEV) during the study and the grade of peripheral ischemia remained unchanged. The mean number of injections was 3.8 (range 3-6) with no significant difference between groups.

CONCLUSIONS

Our data demonstrate a beneficial effect of bevacizumab in ME in eyes with BRVO. A loading phase of three injections led to a significant improvement in vision in both groups, which persisted at week 38. Additional grid laser photocoagulation exhibited no beneficial functional or anatomical effect during the study, nor did it reduce the number of injections. The FAZ area increased significantly in both groups, but overall retinal ischemia did not. Further studies investigating more numerous eyes and longer follow-up are needed to confirm these data.

Combination of Grid Laser Photocoagulation and a Single Intravitreal Ranibizumab as an Efficient and Cost-Effective Treatment Option for Macular Edema Secondary to Branch Retinal Vein Occlusion

Our prospective comparative study of 60 patients aimed to compare the efficacy and feasibility of a single injection ranibizumab versus a single grid laser photocoagulation and versus a combined treatment in macular edema secondary to branch retinal vein occlusion in Asian population. Patients were randomized 1:1:1 (n = 20/group) into grid laser (LAS), the ranibizumab (RAN), and the combination (COM) group. Outcomes were measured as best-corrected visual acuity (BCVA) and central macular thickness (CMT). There were significant differences in mean BCVA between the three groups at 1 week and 1 month (p < 0.05) and in mean CMT at 1 week and 1, 3, 6, and 12 months (p < 0.05). Overall, best results were observed in the combination group. However, the RAN and COM groups achieved very similar results. At 12 months, the CMT in all three groups was decreased compared with baseline (p < 0.05). Our results allow to conclude that the effect of early treatment with a single injection of intravitreal ranibizumab (cost reduction) and the stabilizing effect of grid laser photocoagulation is indeed an effective, feasible, and safe regiment for macular edema secondary to BRVO in Chinese patients, allowing to obviate the need for repeated intravitreal injections and thus reduce the adverse events, therapy duration, patients' malcompliance, and adverse events. A single ranibizumab therapy however is a comparable alternative.

New Developments in the Classification, Pathogenesis, Risk Factors, Natural History, and Treatment of Branch Retinal Vein Occlusion

For years, branch retinal vein occlusion is still a controversial disease in many aspects. An increasing amount of data is available regarding classification, pathogenesis, risk factors, natural history, and therapy of branch retinal vein occlusion. Some of the conclusions may even change our impression of branch retinal vein occlusion. It will be beneficial for our doctors to get a deeper understanding of this disease and improve the treatment skills. The aims of this review is to collect the information above and report new ideas especially from the past a few years.