Intravitreal bevacizumab (Avastin) treatment of macular edema in central retinal vein occlusion: a short-term study

Steroid Treatment in Macular Edema: A Bibliometric Study and Visualization Analysis

The use of steroids to treat macular edema (ME) is a research hotspot in ophthalmology. We utilized CiteSpace and VOSviewer software to evaluate the Web of Science Core Collection publications and to build visualizing maps to describe the research progress in this topic. There were 3,252 publications for three decades during 1988–2021. The number of studies was low during the first 14 years but has risen consistently in the following two decades. The average publications per year were only 4.8 during 1988–2002, which jumped to 113 per year during 2003–2012, and 227 per year during 2013–2021. These publications came from 83 countries/regions, with the United States, Germany, and Italy leading positions. Most studies were published in Investigative Ophthalmology Visual Science, and Ophthalmology was the most cited journal. We found 9,993 authors, with Bandello F having the most publications and Jonas JB being the most frequently co-cited. According to our research, the most popular keyword is triamcinolone acetonide (TA). Macular edema, diabetic macular edema (DME), retinal vein occlusion (RVO), dexamethasone (DEX), fluocinolone acetonide (FA), and some other keywords were commonly studied in this field. In conclusion, the bibliometric analysis provides a comprehensive overview of steroid hotspots and developmental tendencies in the macular edema study. While anti-VEGF therapy is the first-line treatment for DME and RVO-induced macular edema, steroids implant is a valid option for these DME patients not responding to anti-VEGF therapy and non-DME patients with macular edema. Combined therapy with anti-VEGF and steroid agents is vital for future research.

Bevacizumab for diabetic macular oedema: one-year treatment outcomes from the Fight Retinal Blindness! Registry

OBJECTIVES

This study evaluated the 1-year treatment outcomes of bevacizumab for diabetic macular oedema (DMO) in routine clinical practice.

METHODS

A retrospective analysis was performed on 298 eyes of 220 patients with DMO that received intra-vitreal bevacizumab between 1 September 2013 and 31 August 2018 that were tracked by a prospectively designed, web-based observational registry-the Fight Retinal Blindness! Registry.

RESULTS

The mean visual acuity (95% confidence interval [CI]) at 1-year was 3 (2, 5) letters better than a mean (SD) of 68 (15) letters at study entry. Nearly a quarter of eyes achieved ≥20/40. Eyes presenting with better vision (≥20/40) tended to maintain that vision during the period of observation, whereas those presenting with worse vision (<20/40) gained a mean (95% CI) of 9 (5, 13) letters. A mean reduction in the macular thickness was observed over the study period with the central subfield improving by 29 µm (95% CI 17, 40) from a mean (SD) of 402 (109) µm at study entry. Eyes that completed 1 year of follow-up received a median (Q1, Q3) of 7 (4, 9) bevacizumab injections. Sixty-two eyes, ~20%, that started with bevacizumab changed to either another VEGF inhibitor or steroid (triamcinolone) during the period of observation. This did not lead to functional improvement for eyes changed to either ranibizumab or aflibercept despite a further reduction in macular thickness. An improvement in vision and reduction in macular thickness was noted in the 13 eyes that subsequently received triamcinolone. Approximately 10% of eyes dropped out over 12 months, even though their mean visual acuity had improved by seven letters from the initial visit.

CONCLUSIONS

Bevacizumab is an effective treatment for DMO in unselected populations.

Recent advances in ocular drug delivery systems and targeting VEGF receptors for management of ocular angiogenesis: A comprehensive review

Background

Angiogenic ocular diseases address the main source of vision impairment or irreversible vision loss. The angiogenesis process depends on the balance between the pro-angiogenic and anti-angiogenic factors. An imbalance between these factors leads to pathological conditions in the body. The vascular endothelial growth factor is the main cause of pathological conditions in the ocular region. Intravitreal injections of anti-angiogenic drugs are selective, safe, specific and revolutionized treatment for ocular angiogenesis. But intravitreal injections are invasive techniques with other severe complications. The area of targeting vascular endothelial growth factor receptors progresses with novel approaches and therapeutically based hope for best clinical outcomes for patients through the developments in anti-angiogenic therapy.

Main text

The present review article gathers prior knowledge about the vascular endothelial growth factor and associated receptors with other angiogenic and anti-angiogenic factors involved in ocular angiogenesis. A focus on the brief mechanism of vascular endothelial growth factor inhibitors in the treatment of ocular angiogenesis is elaborated. The review also covers various recent novel approaches available for ocular drug delivery by comprising a substantial amount of research works. Besides this, we have also discussed in detail the adoption of nanotechnology-based drug delivery systems in ocular angiogenesis by comprising literature having recent advancements. The clinical applications of nanotechnology in terms of ocular drug delivery, risk analysis and future perspectives relating to the treatment approaches for ocular angiogenesis have also been presented.

Conclusion

The novel ocular drug delivery systems involving nanotechnologies are of great importance in the ophthalmological sector to overcome traditional treatments with many drawbacks. This article gives a detailed insight into the various approaches that are currently available to be a road map for future research in the field of ocular angiogenesis disease management.

Retinal Vascular Resistance Significantly Correlates With Visual Acuity After 1 Year of Anti-VEGF Therapy in Central Retinal Vein Occlusion

Purpose

To investigate whether the resistivity of all retinal vessels, termed total capillary resistance (TCR), after anti-vascular endothelial growth factor (VEGF) treatment was correlated with the outcomes of patients with macular edema secondary to central retinal vein occlusion (CRVO).

Methods

In total, 67 patients with nonischemic CRVO were enrolled in this retrospective observational case series. In each patient, we examined visual acuity; central retinal thickness (CRT); mean blur rate (MBR), which represents retinal blood flow velocity; and TCR. MBR and TCR were measured by laser speckle flowgraphy.

Results

During the 1-year follow-up period, nine of 67 eyes (13.4%) converted to the ischemic type (converted group), whereas 58 eyes (86.6%) remained unchanged (nonischemic group). Mean CRT significantly decreased in all groups; however, the mean visual acuity significantly improved only in the nonischemic group. Mean MBR significantly increased in the nonischemic group but remained unchanged in the converted group. Mean TCR was significantly reduced in the nonischemic group but remained unchanged in the converted group. Multiple linear regression analysis revealed that MBR and TCR were the independent factors with the strongest and second strongest correlations with visual acuity after treatment, respectively.

Conclusions

These findings suggest that measurements of the independent factors MBR and TCR are useful for evaluating anti-VEGF treatments in patients with CRVO.

Translational Relevance

Development of clinically relevant technologies.

Combined Intravitreal Bevacizumab and Laser Photocoagulation to Treat Retinal Arterial Macroaneurysms

Purpose: To investigate the effects of intravitreal bevacizumab injection combined with laser photocoagulation in patients with retinal microaneurysms.Methods: We retrospectively reviewed the medical records of 21 eyes of 21 patients who underwent intravitreal bevacizumab injection and/or laser photocoagulation to treat retinal macroaneurysms. Eleven eyes received the combination therapy (CT) and 10 eyes monotherapy (MT) (either bevacizumab injection or laser photocoagulation). Changes in visual acuity, central macular thickness, macroaneurysm size and location, blood pressure, and the lipid level were compared between the two groups.Results: The mean patient age was 74.0 ± 10.5 years and the mean study period 7.0 ± 5.3 months. The mean macroaneurysm diameter of the CT group was 480.00 ± 292.30 μm and that of the MT group 328.75 ± 87.09 μm. The diameter was significantly larger in the CT group (p = 0.002). The initial visual acuities were 0.91 ± 0.66 and 0.88 ± 0.83 in the CT and MT groups, respectively. At the 4-month follow-up, the visual acuities were 0.33 ± 0.26 and 0.17 ± 0.29 in the CT and MT groups, respectively, and had significantly improved only in the CT group (p = 0.042). The initial central macular thicknesses were 441.82 ± 226.81 and 541.63 ± 401.97 μm in the CT and MT groups, respectively. At the 4-month follow-up, the figures were 293.60 ± 46.10 and 269.00 ± 48.34 μm in the CT and MT groups, respectively, and had significantly decreased only in the CT group (p = 0.043). Compared to the initial findings, the proportion of patients whose final visual acuities improved by more than two lines were 73% and 40%, respectively, thus significantly higher in the CT group (p < 0.001).Conclusions: Combined intravitreal bevacizumab injection and laser photocoagulation treatment of retinal macroaneurysms improve visual acuity and decrease macular thickness.

A comparison of the effect of intravitreal dexamethasone implant on macular and branch retinal vein occlusion. A real life experience

PURPOSE

This study aimed to compare the effects of intravitreal dexamethasone (IVDx) implants on branch retinal vein occlusions (BRVOs) and macular vein occlusions (MVOs).

METHODS

Seventeen consecutive patients with MVO and 18 patients with BRVO, whose foveal thicknesses were greater than 300 µm, were recruited for this study. BRVO and MVO patients were diagnosed by means of fundus fluorescein angiography. Patients were treatment-naive. Initially, each patient in both the BRVO and MVO groups received an IVDx implant, and then a pro re nata IVDx regimen was initiated. Primary outcomes included VA gain, intraocular pressure (IOP) changes, macular ischemia, central macular thickness, retinal neovascularization, and number of IVDx injections. Follow-up time was 12 months.

RESULTS

The MVO group initially had significantly lower central macular thickness and a lower percentage of macular ischemia and systemic hypertension than those in the BRVO group (p = 0.001, 0.045, and 0.010, respectively). There was a statistically significant VA gain in both groups (p < 0.001), but the VA gain of the MVO group was greater than that of the BRVO group (p < 0.001). The mean total number of IVDx injections administered throughout the study period was significantly lower in the MVO group than in the BRVO group (1.3 ± 0.4 vs 2.0 ± 0.0; p = 0.001).

DISCUSSION

MVO and BRVO have different disease characteristics, and IVDx implants were more effective on the visual gain in patients with MVO than that of patients with BRVO who had higher numbers of IVDx injections.

Clinical observation of Dan-Hong Hua-Yu oral solution in treating retinal vein occlusion

INTRODUCTION

Retinal vein occlusion refers to diseases with decreased vision, dilated tortuous retinal veins visible on the fundus, and retinal hemorrhage, edema, and osmosis distributed along the vein. There is still no ideal intervention to treat central retinal vein occlusion. This study plan to observe the efficacy of Dan-Hong Hua-Yu oral solution in treating non-ischemic retinal vein occlusion, in order to provide new treatment ideas.

METHODS/DESIGN

We plan to use random number table method, 64 cases of non-ischemic central retinal vein occlusion that meet the inclusion criteria will be randomly divided into a treatment group and a control group. The intervention group will be treated with Dan-Hong Hua-Yu oral solution according to the syndrome differentiation of Traditional Chinese medicine and the patient's fundus condition. Each group will take 4 weeks as a course of treatment and three consecutive courses of treatment without any interval during the course of treatment. Changes of visual acuity, fundus performance, and total clinical symptoms of patients before and after treatment will be observed.

DISCUSSION

This study will observe the efficacy of Dan-Hong Hua-Yu oral solution in the treatment of non-ischemic central retinal vein occlusion, with a view to providing new treatment ideas.

TRIAL REGISTRATION

ClinicalTrials.gov, ChiCTR2000030625, Registered on March 08, 2020.

Bevacizumab in Wet AMD treatment: A tribute to the thirteen years of experience from the beginning of the anti-VEGF era in Romania

This study aimed to identify and describe anatomical and functional changes on short (1–3 months) and medium (6–12 months) term after intravitreal injections of bevacizumab (Avastin, Genentech) in patients with choroidal neovascularization (CNV) in the context of exudative form of age-related macular degeneration (AMD). We performed a retrospective, analytical, interventional study, based on a series of cases with exudative form of AMD, which also comprised a prospective component related to the inclusion and treatment of the patients with a very new interventional method for that time (2006) and the follow-up of the effects of intravitreal injection of bevacizumab (1.25 mg) therapy in three monthly doses for short (1–3 months) and medium (6–18 months) periods of time. The follow-up of these patients was made by determining visual acuity (VA) as best corrected visual acuity (BCVA) at baseline and at every visit, slit lamp examination with contact or noncontact lenses each time, and optical coherence tomography and/or angiofluorography, applied only for certain patients, at various times of the study. In total, 376 intravitreal injections were administered to 117 eyes of 96 patients. The VA improved in the assessment of 3 months in 77 eyes (66%), either subjective (by the patient) or objectively quantified (by the physician). In 40 eyes (34%), there was no change in VA. In patients for whom optical coherence tomography could be performed, a significant reduction of the macula's thickness was found. The use of bevacizumab in subretinal neovascular membrane treatment is effective and safe on short and medium term, with the improvement of BCVA and reduction of macular edema in a significant number of cases.

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.

RETINAL MICROVASCULATURE AND VISUAL ACUITY AFTER INTRAVITREAL AFLIBERCEPT IN EYES WITH CENTRAL RETINAL VEIN OCCLUSION: An Optical Coherence Tomography Angiography Study

PURPOSE

To investigate vascular perfusion and foveal avascular zone area in the superficial capillary plexus (SCP) and deep capillary plexus (DCP) after intravitreal aflibercept therapy in central retinal vein occlusion eyes and their association with best-corrected visual acuity.

METHODS

Thirty-five subjects with central retinal vein occlusion and macular edema were evaluated. After macular edema resolution following intravitreal aflibercept, subjects underwent optical coherence tomography angiography to measure SCP and DCP perfusion and the foveal avascular zone within a 3 × 3-mm area. Correlations between best-corrected visual acuity and optical coherence tomography angiography measurements were examined.

RESULTS

After intravitreal aflibercept therapy, mean retinal vascular area was 3.41 ± 0.74 mm in the SCP and 3.25 ± 0.91 mm in the DCP. Foveal avascular zone area was 1.03 ± 1.04 mm in the SCP and 1.78 ± 1.73 mm in the DCP. Improved best-corrected visual acuity was significantly associated with better SCP and DCP perfusion (both P < 0.001) and with smaller SCP and DCP foveal avascular zone areas (both P < 0.001). Additionally, SCP and DCP perfusion were negatively correlated with macular edema before treatment (P < 0.05) and ischemia (determined via pretreatment fluorescein angiography, P < 0.05), and positively correlated with photoreceptor integrity (P < 0.001).

CONCLUSION

Patients with better retinal perfusion and less retinal ischemia are associated with better visual outcomes after aflibercept in eyes with central retinal vein occlusion.

Prefilled syringes for intravitreal drug delivery

Intravitreal injections of anti-vascular endothelial growth factor (VEGF) medications play an increasingly critical role in numerous retinal vascular diseases. Initially, anti-VEGF medications came in vials that had to be drawn up by the physician into a syringe for administration. In 2018, the US Food and Drug Administration (US FDA) approved the ranibizumab 0.3 mg prefilled syringe (PFS), and in October 2016, the US FDA approved the ranibizumab 0.5 mg PFS. This article discusses the advantages of the PFS, including reduced injection time, possible reduced risk of endophthalmitis, reduction in intraocular air bubbles and silicone oil droplets, and improved precision in the volume and dose of intravitreal ranibizumab administered, along with possible disadvantages. Implications of the innovation of the PFS on intravitreal injection technique and clinical practice pattern are discussed and reviewed.

Changes in Retinal Microvasculature and Visual Acuity After Antivascular Endothelial Growth Factor Therapy in Retinal Vein Occlusion

Purpose

To investigate the changes in the retinal microvasculature during the course of anti-VEGF therapy in eyes with macular edema due to retinal vein occlusion (RVO) and their association with visual outcomes.

Methods

The vessel density (VD) and foveal avascular zone (FAZ) area in the superficial capillary plexus (SCP) and deep capillary plexus (DCP) were quantitatively measured by optical coherence tomography angiography (OCTA) in 48 consecutive eyes with RVO before and 1, 3, 6, 9, and 12 months after anti-VEGF therapy. Anti-VEGF therapy was performed either with ranibizumab or aflibercept following a pro re nata (PRN) regimen. The correlation between post-treatment best-corrected visual acuity (BCVA) and changes in the retinal microvasculature evaluated by OCTA were assessed.

Results

The BCVA improved significantly at 12 months (P < 0.001). Better BCVA at 12 months was significantly associated with a better VD in the SCP and DCP both at baseline (R2 = 0.524, P < 0.001 and R2 = 0.457, P < 0.001, respectively) and at 12 months (R2 = 0.521, P < 0.001 and R2 = 0.662, P < 0.001, respectively). Overall, both VD and FAZ did not change significantly during the 12 months. However, the progression of nonperfusion was observed in the SCP in 6 (13%) eyes and in the DCP in 10 (21%) eyes. The number of macular edema recurrence was significantly associated with a decrease in the VD (P = 0.006 [SCP] and P < 0.001 [DCP]) and less visual gain (P = 0.02) after treatment.

Conclusions

Anti-VEGF therapy maintains retinal perfusion in most patients with RVO. Preserving retinal perfusion is crucial for better visual outcomes.

Correlation between macular ganglion cell-inner plexiform layer thickness and visual acuity after resolution of the macular edema secondary to central retinal vein occlusion

AIM

To examine the thickness of the ganglion cell-inner plexiform layer (GCIPL) in eyes with resolved macular edema (ME) in non-ischemic central retinal vein occlusion (CRVO), applying spectral-domain optical coherence tomography (SD-OCT), and its relationship with visual acuity.

METHODS

The retrospective observational case-control study included 30 eyes of non-ischemic CRVO patients with resolved ME (ME eyes) after treatment, and 30 eyes of non-ischemic CRVO patients without ME (non-ME eyes). The macular GCIPL thickness, peripapillary retinal nerve fiber layer (pRNFL) thickness and central macular thickness (CMT) were measured on a SD-OCT scan. Linear regression analyses were performed to determine the correlation between the thickness of each and the visual acuity (VA).

RESULTS

No significant difference in average GCIPL thickness, mean pRNFL thickness and CMT were observed between ME group and non-ME group (P=0.296, 0.183, 0.846). But, minimum GCIPL thickness was reduced in ME eyes compared with non-ME eyes (P=0.022). Final VA significantly correlated with the minimum GCIPL thickness in ME eyes (r=-0.482, P=0.007), whereas no correlation was found with average GCIPL thickness, average pRNFL thickness and mean CMT.

CONCLUSION

Minimum GCIPL thickness is reduced in ME eyes compared with non-ME eyes, and correlated with the VA in non-ischemic CRVO. These results propose that inner retinal damage occurring in patients with ME secondary to non-ischemic CRVO may lead to permanent visual defect after treatment.

Pre-treatment clinical features in central retinal vein occlusion that predict visual outcome following intravitreal ranibizumab

Background

Predicting how patients with central retinal vein occlusion (CRVO) will respond to intravitreal anti-VEGF is challenging. The purpose of this study was to identify pre-treatment clinical features in CRVO that predict visual acuity (VA) following intravitreal ranibizumab.

Methods

Medical records, fundus images and optical coherence tomography (OCT) scans of treatment naïve patients with CRVO receiving PRN intravitreal ranibizumab were retrospectively reviewed. Early Treatment Diabetic Retinopathy Study (ETDRS) VA and central retinal thickness (CRT) were recorded at baseline, 3 and 12 months after starting therapy. Regression analysis was used to determine independent predictors of VA at 3 and 12 months follow-up. Possible predictors included baseline VA, age, presence of cotton wool spots (CWS), haemorrhages (few scattered or multiple deep), foveal detachment, CRT, time from presentation to treatment, number of injections given, presence of RAPD, and cause of CRVO.

Results

Data from 52 eyes of 50 patients receiving intravitreal ranibizumab treatment for CRVO were analyzed. The mean pre-treatment VA was 43.3 (SD 22.5) letters, which improved to 52.0 (SD 24.3) letters at 3 months, then dropped to 42.0 (SD 30.26) at 12 months. Baseline CRT reduced from 616.7 μm (SD 272.4) to 346.0 μm (SD 205.2) at 3 months and 304.0 μm (SD 168.3) at 12 months. The following features were predictive of poorer VA after starting intravitreal ranibizumab: Poorer pretreatment VA (3-months, P = 0.010; 12-months, P = 0.006), increasing age (3-months, P = < 0.001; 12-months, P = 0.006), and presence of CWS (3-months, P < 0.001; 12-months, P = 0.045).

Conclusion

Pre-treatment VA, older age, and presence of CWS are easily identifiable clinical features in the hospital setting which help predict visual outcome in patients with CRVO receiving intravitreal ranibizumab.

RETINAL BLOOD FLOW AFTER INTRAVITREAL BEVACIZUMAB IS A PREDICTIVE FACTOR FOR OUTCOMES OF MACULAR EDEMA ASSOCIATED WITH CENTRAL RETINAL VEIN OCCLUSION

PURPOSE

To investigate whether retinal blood flow levels after intravitreal bevacizumab (IVB) treatment are correlated with the outcomes of patients with macular edema secondary to central retinal vein occlusion.

METHODS

This retrospective observational case study enrolled 44 cases nonischemic central retinal vein occlusion. In each patient, visual acuity, central retinal thickness, and mean blur rate, which was measured by laser speckle flowgraphy and represents retinal blood flow velocity, were examined.

RESULTS

At the end of the follow-up period (19.8 ± 8.8 months), 4 of 44 eyes (9.1%) converted to the ischemic type (converted group), whereas 40 (90.9%) remained unchanged (nonischemic group). Mean central retinal thickness significantly decreased and mean visual acuity significantly improved at 1 month after the first IVB injection in each group. Mean mean blur rate in the nonischemic group significantly increased, whereas it was unchanged in the converted group. The difference between the two groups was already significant after the first IVB injection. Subsequently, visual acuity worsened in the converted group. Multiple linear regression analysis indicated that the strongest correlation was between the last visual acuity and the last mean blur rate.

CONCLUSION

Blood flow measurements are useful for evaluating IVB treatments. Blood flow after IVB can predict outcomes in patients with central retinal vein occlusion.

Current Advances in Pharmacotherapy and Technology for Diabetic Retinopathy: A Systematic Review

Diabetic retinopathy (DR) is classically defined by its vascular lesions and damage in the neurons of the retina. The cellular and clinical elements of DR have many features of chronic inflammation. Understanding the individual cell-specific inflammatory changes in the retina may lead to novel therapeutic approaches to prevent vision loss. The systematic use of available pharmacotherapy has been reported as a useful adjunct tool to laser photocoagulation, a gold standard therapy for DR. Direct injections or intravitreal anti-inflammatory and antiangiogenesis agents are widely used pharmacotherapy to effectively treat DR and diabetic macular edema (DME). However, their effectiveness is short term, and the delivery system is often associated with adverse effects, such as cataract and increased intraocular pressure. Further, systemic agents (particularly hypoglycemic, hypolipidemic, and antihypertensive agents) and plants-based drugs have also provided promising treatment in the progression of DR. Recently, advancements in pluripotent stem cells technology enable restoration of retinal functionalities after transplantation of these cells into animals with retinal degeneration. This review paper summarizes the developments in the current and potential pharmacotherapy and therapeutic technology of DR. Literature search was done on online databases, PubMed, Google Scholar, clinitrials.gov, and browsing through individual ophthalmology journals and leading pharmaceutical company websites.

Update on the Use of Anti-VEGF Intravitreal Therapies for Retinal Vein Occlusions

The use of anti-vascular endothelial growth factor (VEGF) therapy in ophthalmology has profoundly changed our management and treatment of conditions such as cystoid macular edema, diabetic macular edema, choroidal neovascularization, and other proliferative retinopathies. Although initially used for the treatment of choroidal neovascularization in neovascular age-related macular degeneration, their application has spread rapidly for other indications as their outcomes have often outperformed previously existing treatments. Retinal vein occlusion (RVO) continues to be one of the leading causes of vision loss secondary to macular edema, in addition to macular ischemia and neovascularization in more severe cases. Before the availability of anti-VEGF therapy, the use of macular grid laser and panretinal photocoagulation was the mainstay of treatment of macular edema and neovascularization, respectively, in patients with RVOs. Two landmarks studies established the guidelines of these treatments for nearly a quarter century. Since the availability of anti-VEGF agents, there has been a paradigm shift in the treatment of RVO. Most importantly, there has also been a significant improvement in visual outcomes in these patients. The goal of this article is to provide a review of the pertinent clinical studies that have investigated the use of anti-VEGF in patients with retinal vein occlusions.

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.

Evaluation of vitreoretinal interface changes in patients receiving intravitreal anti-VEGF therapy

PURPOSE

To study the effects of repeated intravitreal injection of anti-VEGF drug bevacizumab on the vitreoretinal interface (VRI).

METHODS

Patients undergoing intravitreal injection of bevacizumab were enrolled. Eyes with media haze, uveitis, high myopia, history of cataract surgery or laser capsulotomy in last 6 months and complicated pseudophakia were excluded. VRI evaluation was done monthly for a minimum of 6 months. The nature and timing of the change(s) event was recorded.

RESULTS

A total of 100 eyes were evaluated. Thirty-seven eyes developed new vitreoretinal interface change event (VICE). Pseudophakia (OR = 5.23, 95% CI = 1.99-14.07, p = 0.001), pre-injection VRI abnormality (OR = 2.63, 95% CI = 1.13-6.14, p = 0.024) and older age at enrollment (62.6 ± 13.9 vs. 56.3 ± 14 years) were risk factors for development of VICE. Eighty percent of interface events occurred in the first 3 months of therapy. Eight needed surgical intervention for consequences of vitreoretinal separation.

CONCLUSION

VICE is not infrequent in eyes receiving anti-VEGF therapy though rarely need surgical intervention. The first 3 months are the critical months to watch out for these events. The treating ophthalmologists must keep the risk factors for development of in mind and monitor and counsel patients accordingly.

Comparison between "early" or "late" intravitreal injection of dexamethasone implant in branch (BRVO) or central (CRVO) retinal vein occlusion: six-months follow-up

AIM

The aim of this study was to compare early and late injections of intravitreal dexamethasone implant in patients affected by central retinal vein occlusion (CRVO) or branch retinal vein occlusion (BRVO) with a six-months follow-up. We assessed whether an earlier treatment start (within seven days from diagnosis) could be more beneficial than a delayed (or late) treatment start (after seven days).

MATERIALS AND METHODS

The study included 81 patients (81 eyes) affected by retinal vein occlusion. Best corrected visual acuity was assessed through Early Treatment Diabetic Retinopathy Study (ETDRS) while central macular thickness (CMT) was measured by spectral-domain optical coherence tomography.

RESULTS

Both types of patients had a positive therapeutic response to dexamethasone, with an increase in visual acuity (ETDRS) and CMT reduction. CRVO patients were characterized by lower ETDRS values at baseline and at the end of the follow-up as compared to BRVO. CRVO patients showed higher CMT values at baseline, after three and six months from injection. No significant differences in therapeutic response to dexamethasone were observed between patients treated early or late, regardless of RVO type.

CONCLUSIONS

This study demonstrates that the therapeutic properties of dexamethasone implant are not significantly influenced by an early or late treatment start in patients affected by BRVO and CRVO, although its therapeutic efficacy seems greater in the former type.

Intraocular cytokines in retinal vein occlusion and its relation to the efficiency of anti-vascular endothelial growth factor therapy

Purpose:

To analyze the change in the concentration of intraocular cytokines (ICs) in patients with retinal vein occlusion (RVO) before and after intravitreal ranibizumab therapy (IVR), and to find the correlations of IC with clinical activity of RVO and efficiency of treatment.

Materials and Methods:

Forty-four patients aged 46–79 years old (mean age: 60.7 ± 7.5 years old) with RVO and macular edema (18 patients – with central RVO, 26 – with branch RVO) treated with IVR were included into the study. The concentrations of 27 cytokines were simultaneously measured in aqueous humor by flow fluorometry using Bio-Plex Pro Human Cytokine Panel, 27-Plex (Bio-Rad Laboratories, USA) at baseline and after the first IVR. Control group consisted of 20 age-matched patients.

Results:

The levels of 11 cytokines (vascular endothelial growth factor [VEGF], receptor antagonist interleukin-1, interleukin-6 [IL-6], IL-8, IL-9, IL-10, IL-12r70, IL-13, IL-15, monocyte chemotactic protein-1 [MCP-1], regulated on activation, normal T expressed and secreted) were significantly (P < 0.05) different compared to control and significantly (P < 0.05) changed after IVR both in central and branch RVO. The patients were divided into two groups: the first -“effective” and the second - “partially effective” therapy. The second group characterized by the higher concentrations of VEGF, IL-8, IL-10, IL-17, and MCP-1 at baseline compared to the first group.

Conclusion:

The patients with RVO were characterized by the increased levels of VEGF and other pro- and anti-inflammatory cytokines and chemokines. Aqueous concentration of cytokines were different in patients with central and branch RVO and significantly changed after IVR. Insufficient response to IVR was associated with activation of immune-inflammatory processes.

SCORE2 Report 2: Study Design and Baseline Characteristics

PURPOSE

To describe the design and baseline characteristics of participants in the Study of COmparative Treatments for REtinal Vein Occlusion 2 (SCORE2) and to compare with cohorts from other retinal vein occlusion trials.

DESIGN

Phase III prospective, multicenter, randomized clinical trial designed to assess whether intravitreal bevacizumab is noninferior to intravitreal aflibercept for treatment of decreased vision attributable to macular edema associated with central retinal vein occlusion (CRVO) or hemiretinal vein occlusion (HRVO).

PARTICIPANTS

Total of 362 participants: 307 with CRVO and 55 with HRVO.

METHODS

Demographic and study eye characteristics are summarized and compared between CRVO and HRVO study participants.

MAIN OUTCOME MEASURES

Baseline ophthalmic characteristics, including visual acuity and retinal thickness, and medical history characteristics, including hypertension, diabetes mellitus, and coronary artery disease.

RESULTS

The mean age of participants was 69 years, 76% of participants were white, and 90% were non-Hispanic. There was a racial disparity with respect to disease type, with 38% of HRVO patients being black compared with 11% of CRVO patients (P value adjusted for multiple testing = 0.0001). This is similar to findings from the previous SCORE Study. Comorbidities included hypertension (77%), diabetes mellitus (31%), and coronary artery disease (15%). At baseline, mean visual acuity letter score was 50 (20/100) (range, 19-73 [20/400 to 20/40]), mean optical coherence tomography (OCT)-measured central subfield thickness was 678 μm (range, 300-1203 μm), and mean number of months from diagnosis of macular edema to randomization was 6 (range, 0-104 months). One hundred twenty (33%) SCORE2 participants had been treated previously with anti-vascular endothelial growth factor (anti-VEGF) therapy, with these participants having baseline visual acuity letter score and OCT-measured central subfield thickness similar to those without prior anti-VEGF treatment, but longer mean duration of macular edema before randomization (18 months vs. 1 month for those without prior anti-VEGF treatment; P < 0.0001).

CONCLUSIONS

The SCORE2 cohort is a heterogeneous population, including both CRVO and HRVO eyes and both treatment-naïve eyes and eyes treated previously with anti-VEGF, which will allow study results to have broad applicability to CRVO and HRVO patients receiving treatment for macular edema. Similarities of the baseline characteristics of the SCORE2 population to other CRVO trial cohorts will allow meaningful comparisons of outcome results across trials.

Short-term efficacy of intravitreal triamcinolone acetonide for macular edema secondary to retinal vein occlusion that is refractory to intravitreal bevacizumab

AIMS

To evaluate the 1-month efficacy of intravitreal triamcinolone acetonide (TA) in treating macular edema secondary to retinal vein occlusion (RVO) that was refractory to intravitreal bevacizumab.

MATERIALS AND METHODS

This retrospective, observational study included 23 eyes from 23 patients with macular edema secondary to RVO. Macular edema that did not respond to two or more consecutive intravitreal bevacizumab injections was treated with intravitreal TA. Central foveal thickness (CFT) and best-corrected visual acuity (BCVA) were compared before and one month after TA injection.

RESULTS

Fifteen eyes were diagnosed with central RVO, and eight eyes were diagnosed with branch RVO. All patients were previously treated with 2.4 ± 0.6 intravitreal bevacizumab injections. The TA injection was performed, on average, 5.8 ± 1.4 weeks after the last bevacizumab injection. The CFT before TA injection was 516.6 ± 112.4 μm and significantly decreased to 402.3 ± 159.7 μm after TA therapy (P < 0.001). The logarithm of the minimal angle of resolution BCVA was 0.72 ± 0.34 before TA therapy and was not significantly improved by the treatment (0.67 ± 0.35, P = 0.119), despite a decrease in CFT. However, seven eyes (30.4%) had a BCVA gain of one or more lines.

CONCLUSIONS

Intravitreal TA therapy was beneficial in some patients with macular edema secondary to RVO that was refractory to intravitreal bevacizumab therapy. This study suggests that intravitreal TA should be considered as a treatment option for refractory macular edema.

Comparison between ranibizumab and aflibercept for macular edema associated with central retinal vein occlusion

PURPOSE

We compared the efficacy of bimonthly intravitreal injections of ranibizumab (IVR) with that of bimonthly intravitreal injections of aflibercept (IVA) in two prospective, consecutive groups of patients with macular edema (ME) secondary to central retinal vein occlusion (CRVO).

PATIENTS AND METHODS

Eyes with ME after CRVO received either bimonthly IVR (ranibizumab group; n = 13) or IVA (aflibercept group; n = 13) injections and were followed monthly for 6 months. Three patients in the ranibizumab group and two in the aflibercept group were lost to follow-up and excluded from the study. The best-corrected visual acuity (BCVA), central foveal thickness (CFT) on optical coherence tomography, and aqueous vascular endothelial growth factor (VEGF) concentrations were evaluated before and after treatment.

RESULTS

From baseline to month 6, significant improvements occurred in mean logMAR BCVA (ranibizumab group: 0.78-0.47; p < 0.05; aflibercept group: 0.74-0.54; p < 0.05) and mean CFT (ranibizumab group: 685-311 µm; p < 0.05; aflibercept group: 695-230 µm; p < 0.05). Fluctuations in CFT were seen at months 2, 4, and 6 in the ranibizumab group. Mean aqueous VEGF concentration decreased from baseline to month 2 in the ranibizumab group (509.9-348.2 pg/ml) and aflibercept group (412.1 pg/ml to undetectable limits in eight of 11 eyes and to 13.6, 15.6, and 24.1 pg/ml in the other three eyes, respectively).

CONCLUSIONS

There was no significant improvement of visual acuity in one group compared with another; VEGF may not be completely neutralized by bimonthly injections of ranibizumab.

Long-term Outcomes After Preoperative Intravitreal Injection of Bevacizumab Before Trabeculectomy for Neovascular Glaucoma

PURPOSE

To evaluate the long-term (>3 y) outcomes of patients given preoperative intravitreal bevacizumab (IVB) injection before trabeculectomy for neovascular glaucoma (NVG).

METHOD

We performed a retrospective study of a consecutive series of 12 eyes of 11 patients who underwent trabeculectomy with mitomycin C combined with preoperative IVB for NVG at our institution between April 2009 and April 2010. The mean follow-up period was 43.0±7.0 months (range, 36 to 51 mo), and all patients were followed up for at least 36 months. Surgical success was defined as an intraocular pressure (IOP) of ≤21 mm Hg with or without topical ocular hypotensive medication.

RESULT

The cumulative surgical success rate was 83.3% at 1 year and 83.3% at 3 years. The mean IOP before surgery was 42.7±9.2 mm Hg, whereas the mean postoperative IOP was significantly lower, being 15.1±3.7 mm Hg at 1 year and 14.2±3.2 mm Hg at 3 years (P<0.01).In contrast, no significant change of the mean visual acuity as compared with the preoperative visual acuity was observed at the follow-up carried out 3 years after the surgery. Intraoperative and early postoperative hyphema was seen in 2 eyes. Recurrence of neovascularization requiring additional IVB injection was seen in 3 eyes.

CONCLUSIONS

Preoperative IVB injection before trabeculectomy for NVG might be effective over the long-term (>3 y) control of the IOP.

Volume-Rendered Optical Coherence Tomography of Retinal Vein Occlusion Pilot Study

PURPOSE

To investigate the retinal vascular findings and associated cystoid edema in the central macula of eyes with retinal vein occlusion using volume-rendered angiographic and structural optical coherence tomography.

STUDY DESIGN

Observational case series.

METHODS

In this retrospective study 12 eyes of 12 consecutive patients, 3 with branch and 9 with central retinal vein occlusion, were imaged in 27 sessions with optical coherence tomography (OCT) using split-spectrum amplitude decorrelation. The structural OCT data were segmented for cystoid spaces and integrated into the angiographic data for subsequent volume rendering. The inner and deep vascular plexus were analyzed in relation to cystoid macular edema with retention of depth information.

RESULTS

Retinal vascular flow abnormalities were demonstrated by flow voids with abnormal vascular morphology in the inner vascular layer and varying flow loss in the deep vascular plexus. Areas of cystoid edema were associated with topographically co-localizing flow voids in the deep vascular layer. Treatment with intravitreous anti-vascular endothelial growth factor injections resulted in resolution of edema but no change in flow patterns in either the inner or deep plexus. Recurrence of edema happened in the same areas of altered inner and absent deep vascular plexus flow signal.

CONCLUSIONS

Cystoid macular edema in retinal vein occlusion occurred in relation to altered inner plexus and absent deep vascular plexus flow. This pattern of cystoid fluid accumulation is similar to that seen in diabetic retinopathy and may represent an important underlying pathophysiologic foundation for cystoid macular edema in retinal vascular diseases.

Bevacizumab clearance through the iridocorneal angle following intravitreal injection in a rat model

Antivascular endothelial growth factor (Anti-VEGF) agents have been widely used for a variety of ocular disorders. The etiology of sustained ocular hypertension following intravitreal administration of anti-VEGF agents is yet to be unraveled. Our study investigates and characterizes the presence of intravitreally injected bevacizumab in the aqueous outflow channels of a rat model. Choroidal neovascularization (CNV) was induced by diode laser photocoagulation to the right eye of twelve Brown Norway rats. Bevacizumab (25 mg/ml) was injected intravitreally after 3 days. Immediately after bevacizumab injection, and 3, 6, 24 and 48 h later, animals were euthanized for immunofluorescence staining. Donkey anti-human IgG labeled with Alexa Fluor(®) 488 was used for bevacizumab immunoreactivity detection. Anti-CD31 antibody was used as a marker for Schlemm's canal endothelial cells. Untreated eyes were used as negative controls. The intensity of the immunostaining was analyzed qualitatively. Bevacizumab immunoreactivity was found in the aqueous outflow channels including the trabecular meshwork and Schlemm's canal immediately after injection, and declined incrementally within the following hours. Forty-eight hours after the injection, no bevacizumab staining was detected in the aqueous outflow channel structures. Our manuscript demonstrates the presence of bevacizumab in the trabecular meshwork and Schlemm's canal structures after intravitreal injection in a CNV induced rat model. Bevacizumab molecules passed through the aqueous outflow channels within 48 h after intravitreal bevacizumab injection.

The effect of intravitreal injection of vehicle solutions on form deprivation myopia in tree shrews

lntravitreal injection of substances dissolved in a vehicle solution is a common tool used to assess retinal function. We examined the effect of injection procedures (three groups) and vehicle solutions (four groups) on the development of form deprivation myopia (FDM) in juvenile tree shrews, mammals closely related to primates, starting at 24 days of visual experience (about 45 days of age). In seven groups (n = 7 per group), the myopia produced by monocular form deprivation (FD) was measured daily for 12 days during an 11-day treatment period. The FD eye was randomly selected; the contralateral eye served as an untreated control. The refractive state of both eyes was measured daily, starting just before FD began (day 1); axial component dimensions were measured on day 1 and after eleven days of treatment (day 12). Procedure groups: the myopia (treated eye - control eye refraction) in the FD group was the reference. The sham group only underwent brief daily anesthesia and opening of the conjunctiva to expose the sclera. The puncture group, in addition, had a pipette inserted daily into the vitreous. In four vehicle groups, 5 μL of vehicle was injected daily. The NaCl group received 0.85% NaCl. In the NaCl + ascorbic acid group, 1 mg/mL of ascorbic acid was added. The water group received sterile water. The water + ascorbic acid group received water with ascorbic acid (1 mg/mL). We found that the procedures associated with intravitreal injections (anesthesia, opening of the conjunctiva, and puncture of the sclera) did not significantly affect the development of FDM. However, injecting 5 μL of any of the four vehicle solutions slowed the development of FDM. NaCl had a small effect; myopia development in the last 6 days (-0.15 ± 0.08 D/day) was significantly less than in the FD group (-0.55 ± 0.06 D/day). NaCl + Ascorbic acid further slowed the development of FDM on several treatment days. H2O (-0.09 ± 0.05 D/day) and H2O + ascorbic acid (-0.08 ± 0.05 D/day) both almost completely blocked myopia development. The treated eye vitreous chamber elongation, compared with the control eye, in all groups was consistent with the amount of myopia. When FD continued (days 12-16) without injections in the water and water + ascorbic acid groups, the rate of myopia development quickly increased. Thus, it appears the vehicles affected retinal signaling rather than causing damage. The effect of water and water + ascorbic acid may be due to reduced osmolality or ionic concentration near the tip of the injection pipette. The effect of ascorbic acid, compared to NaCl alone, may be due to its reported dopaminergic activity.

Cotton Wool Spots after Anti-Vascular Endothelial Growth Factor Therapy for Macular Edema Associated with Central Retinal Vein Occlusion

PURPOSE

To report a case series, whereby we encountered a transient increase in retinal cotton wool spots (CWS) following anti-vascular endothelial growth factor (anti-VEGF) therapy for the treatment of macular edema secondary to central retinal vein occlusion (CRVO).

METHODS

Eighteen eyes were treated with intravitreal aflibercept (IVA), and 5 were treated with intravitreal ranibizumab (IVR). Fundus photographs obtained 1 month after initial IVA or IVR injections were retrospectively evaluated for the presence of CWS.

RESULTS

Twenty-one (91.3%) patients had the following systemic diseases: hypertension, diabetes mellitus without retinopathy, dyslipidemia, or chronic renal failure requiring dialysis. One month after treatment, reduced macular edema was observed in 21 (91.3%) eyes. Initial injections facilitated complete resolution in 14 eyes, and CWS gradually became fainter with additional injections.

CONCLUSION

Some eyes with CRVO-related macular edema can show a transient increase in CWS after initial anti-VEGF therapy; however, macular edema, retinal hemorrhage, and visual acuity were improved in almost every case.

Spectral domain optical coherence tomographic analysis of healthy retina in branch retinal vein occlusion and its response to antiangiogenic therapy

PURPOSE

To propose a model that measures the effect of intravitreal bevacizumab (IVB) on relatively healthy retina. The purpose is to analyze the remote effect of a branch retinal vein occlusion in the healthy retina, to determine the response it may have to IVB, and to determine if IVB has an atrophic effect on the healthy retina.

METHODS

Retrospective, longitudinal comparative analysis of patients with branch retinal vein occlusion treated with IVB. Eyes were divided into experimental (branch retinal vein occlusion eye) and control (contralateral eye) groups. Each eye was analyzed for thickness and area. Thickness measurements were performed for total retinal thickness, inner retina thickness, and outer retina thickness. Area was measured for photoreceptors, choroid, and total retina.

RESULTS

Eighteen eyes of 9 patients. For thickness analysis, 1,050 scans were studied, and 126 measurements were performed on 42 scans for area analysis. No difference was observed for thickness, except for inner retina thickness. No difference was observed for area. No difference was observed when analyzing a cumulative exposure to IVB.

CONCLUSION

There is no evidence to suggest an atrophic effect caused by IVB when analyzing thickness or area in this experiment. This model could be used to analyze the long-term safety of IVB in larger studies.

Flicker electroretinograms before and after intravitreal ranibizumab injection in eyes with central retinal vein occlusion

PURPOSE

To compare the amplitudes and implicit times of the flicker electroretinograms before and after an intravitreal injection of ranibizumab (IVR) in eyes with a central retinal vein occlusion (CRVO).

METHODS

We reviewed the medical records of 15 consecutive patients who had macular oedema secondary to CRVO and had received an IVR at the Nagoya University Hospital from November 2013 to July 2014. Flicker ERGs were recorded with both the RETeval(™) system and a conventional ERG system before the IVR. One month after the IVR, recordings were repeated with only the RETeval(™) system.

RESULTS

The mean implicit times of the flicker ERGs of the affected eyes recorded with the RETeval(™) system were significantly longer than that of the fellow eyes (32.2 ± 2.6 msec versus 28.1 ± 1.2 msec, p < 0.001). One month after the IVR, the implicit times of the flicker ERGs of affected eyes were significantly shortened from 32.2 ± 2.6 to 30.6 ± 2.2 msec (p < 0.001).

CONCLUSIONS

The shortening of the implicit times of the flicker ERGs after the IVR indicates an improvement of retinal function after anti-VEGF therapy for CRVO eyes.

[Intraocular cytokines imbalance in retinal vein occlusion and its impact on the efficacy of anti-angiogenic therapy]

AIM

To study the concentrations of intraocular cytokines in patients with retinal vein occlusion (RVO) before and after intravitreal ranibizumab injection and to compare the results with clinical activity of the disease and treatment efficacy.

MATERIAL AND METHODS

A comprehensive ophthalmological examination of 44 patients with RVO and macular edema was performed. Intraocular fluid was first collected before the intravitreal injection. Cytokines concentrations were measured using Bio-Plex Pro Human Cytokine 27-plex Panel (Bio-Rad Laboratories, USA) for flow cytometry. The test was repeated 1 month after the injection.

RESULTS

A total of 11 cytokines were reliably detected. After ranibizumab injections certain angiogenic (VEGF) and proinflammatory (IL-6, IL-8, IL-13, IL-15, MCP-1) factors appeared to be significantly suppressed. Clinical efficacy of the therapy correlated with the degree of cytokines suppression, which in turn depended on the severity of ocular involvement at baseline.

CONCLUSIONS

Retinal vein occlusion pathogenesis involves a cascade of immune and inflammatory processes, including activation of not only VEGF but also quite a few inflammatory and chemotactic factors, whose activity depends on the extent of ischemic damage in the retina.

Outcomes of Patients Initially Treated with Intravitreal Bevacizumab for Central Retinal Vein Occlusion: Long-Term Follow-Up

BACKGROUND AND OBJECTIVE

To assess outcomes of visual acuity (VA) and central retinal thickness (RT) in patients with macular edema (ME) secondary to central retinal vein occlusion (CRVO) who were initially treated with bevacizumab and followed for up to four years.

STUDY DESIGN/MATERIALS AND METHODS

In this observational case series, 51 patients with non-ischemic and ischemic CRVO who had initial treatment with bevacizumab were included. Main outcome measures were VA and RT at one year, with follow-up of up to four years.

RESULTS

Mean VA improved from 20/214 at baseline to 20/107 at one year (p = 0.0009) and this improvement was maintained clinically at four years. RT decreased from 595 μm to 339 μm at one year (p = 0.0027) and this was maintained at four years.

CONCLUSION

Patients who received bevacizumab as initial therapy for ME from CRVO maintained VA and RT improvement for up to four years.

Efficacy and visual prognostic factors of intravitreal bevacizumab as needed for macular edema secondary to central retinal vein occlusion

PURPOSE

Our aim was to investigate the efficacy and prognostic factors of intraocular injections of bevacizumab as needed in patients with macular edema secondary to central retinal vein occlusion (CRVO).

METHODS

This is a retrospective study including 28 eyes of 27 consecutive patients with macular edema due to CRVO and followed for at least 6 months. The mean age of the patients was 66.3 years. The patients underwent an intravitreal injection of bevacizumab (1.25 mg) at the initial visit. Retreatments were performed when macular edema was persistent or worsened (as-needed regimen). The primary outcome measure was the mean change in best-corrected visual acuity (BCVA). The change in central retinal thickness (CRT) was evaluated as the secondary outcome. Finally, the factors useful for predicting BCVA outcome were determined.

RESULTS

The mean number of injections was 1.8 over a period of 6 months. The mean BCVA (logarithm of minimum angle of resolution) was significantly improved at 1 (-0.097), 3 (-0.14), and 6 months (-0.25) after the initial injection (P<0.05, <0.01, and <0.001, respectively). The mean CRT was also improved significantly at 1 (-250.4), 3 (-150.0), and 6 months (-187.2) (P<0.001 each). Earlier treatment and better improvement in BCVA at 1 month after the initial treatment were the prognostic factors significantly associated with better visual outcomes at 6 months (P=0.047 and 0.029, respectively).

CONCLUSION

Intravitreal injection of bevacizumab as needed significantly improved visual acuity and macular edema in CRVO patients. Time before the treatment and early response to the treatment were important factors for the visual outcome.

Rebound neovascularization during bevacizumab therapy

PURPOSE

To present two cases of rebound neovascularization after bevacizumab treatment.

METHODS

Observational, retrospective case report. A 42-year-old male patient with proliferative diabetic retinopathy and a 68-year-old man with central retinal vein occlusion received treatment with panretinal photocoagulation and intravitreal bevacizumab.

RESULTS

Both patients showed significant improvement with regression of neovascular vessels after treatment. Nevertheless, on cessation of treatment because of loss to follow-up, both presented with massive neovascularization. This was significantly more severe than the initial presentation.

CONCLUSION

After initial suppression of vascular endothelial growth factor by bevacizumab, a rebound phenomenon of neovascularization can occur.

Pathogenesis, prevention, diagnosis and management of retinal vein occlusion

Retinal vein occlusion (RVO) is the second vascular retinal cause of visual loss and defined by the occlusion of a retinal vein. It is divided into branch retinal vein occlusion or central retinal vein occlusion, depending on the location of occlusion. RVO has severe medical, financial and social implications on the patients. The diagnosis of the disease is easier nowadays with the use of spectral domain optical coherence tomography and fluorescein angiography. The treatment options for RVO have changed dramatically over the past few years with the introduction of the intravitreal injections of dexamethasone (Ozurdex), bevacizumab (Avastin), ranibizumab (Lucentis) and aflibercept (EYLEA), along with the panretinal laser photocoagulation, abandoning former treatment modalities and surgical solution. This manuscript is a review of current literature about RVO with emphasize on the pathophysiology, risk factors and prevention, diagnosis and sub-group categorization and treatments including medical and surgical. Since no official guidelines are available for the treatment of RVO patients, and considering the latest developments in the treatment options, and the variety of follow-up and treatment modalities, this manuscript aims to provide tools and knowledge to guide the physician in treating RVO patients, based on the latest publications from the literature and on several of the patients characteristics.

Anti-vascular endothelial growth factor for diabetic macular oedema

BACKGROUND

Diabetic macular oedema (DMO) is a common complication of diabetic retinopathy. Although grid or focal laser photocoagulation has been shown to reduce the risk of visual loss in DMO, or clinically significant macular oedema (CSMO), vision is rarely improved. Antiangiogenic therapy with anti-vascular endothelial growth factor (anti-VEGF) modalities is used to try to improve vision in people with DMO.

OBJECTIVES

To investigate the effects in preserving and improving vision and acceptability, including the safety, compliance with therapy and quality of life, of antiangiogenic therapy with anti-VEGF modalities for the treatment of DMO.

SEARCH METHODS

We searched CENTRAL (which contains the Cochrane Eyes and Vision Group Trials Register) (2014, Issue 3), Ovid MEDLINE, Ovid MEDLINE In-Process and Other Non-Indexed Citations, Ovid MEDLINE Daily, Ovid OLDMEDLINE (January 1946 to April 2014), EMBASE (January 1980 to April 2014), Latin American and Caribbean Health Sciences Literature Database (LILACS) (January 1982 to April 2014), the metaRegister of Controlled Trials (mRCT) (www.controlled-trials.com), ClinicalTrials.gov (www.clinicaltrials.gov) and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) (www.who.int/ictrp/search/en). We did not use any date or language restrictions in the electronic searches for trials. We last searched the electronic databases on 28 April 2014.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) comparing any antiangiogenic drugs with an anti-VEGF mechanism of action versus another treatment, sham treatment or no treatment in people with DMO.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by The Cochrane Collaboration. The risk ratios (RR) for visual loss and visual gain of three or more lines of logMAR visual acuity were estimated at one year of follow-up (plus or minus six months) after treatment initiation.

MAIN RESULTS

Eighteen studies provided data on four comparisons of interest in this review. Participants in the trials had central DMO and moderate vision loss.Compared with grid laser photocoagulation, people treated with antiangiogenic therapy were more likely to gain 3 or more lines of vision at one year (RR 3.6, 95% confidence interval (CI) 2.7 to 4.8, 10 studies, 1333 cases, high quality evidence) and less likely to lose 3 or more lines of vision (RR 0.11, 95% CI 0.05 to 0.24, 7 studies, 1086 cases, high quality evidence). In meta-analyses, no significant subgroup difference was demonstrated between bevacizumab, ranibizumab and aflibercept for the two primary outcomes, but there was little power to detect a difference. The quality of the evidence was judged to be high, because the effect was large, precisely measured and did not vary across studies, although some studies were at high or unclear risk of bias for one or more domains. Regarding absolute benefit, we estimated that 8 out of 100 participants with DMO may gain 3 or more lines of visual acuity using photocoagulation whereas 28 would do so with antiangiogenic therapy, meaning that 100 participants need to be treated with antiangiogenic therapy to allow 20 more people (95% CI 13 to 29) to markedly improve their vision after one year. People treated with anti-VEGF on average had 1.6 lines better vision (95% CI 1.4 to 1.8) after one year compared to laser photocoagulation (9 studies, 1292 cases, high quality evidence). To achieve this result, seven to nine injections were delivered in the first year and three or four in the second, in larger studies adopting either as needed regimens with monthly monitoring or fixed regimens.In other analyses antiangiogenic therapy was more effective than sham (3 studies on 497 analysed participants, high quality evidence) and ranibizumab associated with laser was more effective than laser alone (4 studies on 919 participants, high quality evidence).Ocular severe adverse events, such as endophthalmitis, were rare in the included studies. Meta-analyses conducted for all antiangiogenic drugs compared with either sham or photocoagulation did not show a significant difference regarding serious systemic adverse events (15 studies, 441 events in 2985 participants, RR 0.98, 95% CI 0.83 to 1.17), arterial thromboembolic events (14 studies, 129 events in 3034 participants, RR 0.89, 95% CI 0.63 to 1.25) and overall mortality (63 events in 3562 participants, RR 0.88, 95% CI 0.52 to 1.47). We judged the quality of the evidence on adverse effects as moderate due to partial reporting of safety data and the exclusion of participants with previous cardiovascular events in some studies.

AUTHORS' CONCLUSIONS

There is high quality evidence that antiangiogenic drugs provide a benefit compared to current therapeutic options for DMO, that is grid laser photocoagulation, in clinical trial populations at one or two years. Future research should investigate differences between drugs, effectiveness under real-world monitoring and treatment conditions, and safety in high-risk populations, particularly regarding cardiovascular risk.

Intravitreal bevacizumab in acute central/hemicentral retinal vein occlusions: three-year results of a prospective clinical study

PURPOSE

To prospectively evaluate the effects of intravitreal bevacizumab (IVB, Avastin; Genentech, Inc., San Francisco, CA) injections in patients with acute central/hemicentral retinal vein occlusions (C/HCRVOs) (≤1 month after the occlusion was diagnosed) over the course of 3 years.

METHODS

The study included 57 patients with unilateral acute C/HCRVOs. Initially, the treatment for acute C/HCRVO patients consisted of 4 consecutive IVB injections administered off-label at a dose of 2.5 mg per injection, with each injection spaced ∼45 days apart. Thereafter, IVB therapy was flexible, and subsequent injections were administered during scheduled visits whenever a best corrected visual acuity (BCVA) loss of ≥5 Early Treatment Diabetic Retinopathy Study (ETDRS) letters occurred and/or iris/angle neovascularization appeared (regardless of the intraocular pressure level). Changes in the BCVA and foveal thickness (FT), number of IVB injections administered, and incidence of neovascular glaucoma (NVG) were estimated.

RESULTS

The increase in the BCVA score at month 36 was 17.15 (ETDRS letters) (P<0.0001) in cases of nonischemic and 26.81 (ETDRS letters) (P<0.01) in cases of ischemic occlusions. At the end of the follow-up, the proportion of BCVA score improvements greater than 15 ETDRS letters was similar in patients with both forms of occlusions (measured in 45.5% of nonischemic and 45.8% of ischemic patients) (P=0.977). There were significant reductions in FT from baseline values to 230±40.50 μm (P=0.0001) in patients with nonischemic occlusions and 270±40.50 μm (P=0.0001) in patients with ischemic forms. There was a significant difference (P<0.03) in the number of IVB injections administered in patients with nonischemic C/HCRVOs (8.7±1.58) compared to patients with ischemic occlusions (9.7±1.78). NVG occurred in 2 cases of ischemic occlusions.

CONCLUSIONS

The 3-year IVB therapy provided sustained vision and FT gains in most phakic patients with acute C/HCRVOs, making this treatment option a rational and viable therapeutic strategy. Bevacizumab was more effective in patients with ischemic occlusions who required a significantly higher number of injections.

Changes in Retinal Nerve Fiber Layer Thickness after Two Intravitreal Bevacizumab Injections for Wet Type Age-related Macular Degeneration

PURPOSE

To evaluate the effect of two intravitreal bevacizumab (IVB) injections on peripapillary retinal nerve fiber layer (RNFL) thickness in patients with wet type age-related macular degeneration (ARMD).

METHODS

This prospective interventional case series included 18 eyes of 18 patients receiving two IVB injections within a 6 weeks interval for treatment of wet type ARMD. Peripapillary RNFL thickness was measured prior to the first injection, and 12 and 24 weeks afterwards by optical coherence tomography (3D OCT-1000, Topcon Corporation, Tokyo, Japan). Mean RNFL thickness and values in the four peripapillary quadrants were compared at baseline, and 12 and 24 weeks after initial injection.

RESULTS

Mean RNFL thickness was 89 ± 21 μm at baseline which was significantly reduced to 82 ± 15 μm at 12 weeks (P = 0.021). At final follow-up (week 24), mean RNFL thickness reached 87 ± 23 μm and was comparable to baseline values (P = 0.356). Only the temporal quadrant showed a significant reduction in RNFL thickness at 12 weeks (P = 0.033); this quadrant followed the same pattern of change as the mean RNFL thickness, becoming comparable to pre-injection values at 24 weeks (P = 0. 298).

CONCLUSION

RNFL thickness may decrease temporarily following two IVB injections in patients with wet type ARMD; however, in the long-term no significant change was detectable from baseline values.

Effect of bevacizumab (Avastin (TM) ) on mitochondrial function of in vitro retinal pigment epithelial, neurosensory retinal and microvascular endothelial cells

Purpose:

To evaluate the effect of bevacizumab on the mitochondrial function of human retinal pigment epithelial (ARPE-19), rat neurosensory retinal (R28) and human microvascular endothelial (HMVEC) cells in culture.

Materials and Methods:

ARPE-19 and R28 cells were treated with 0.125, 0.25, 0.50 and 1 mg/ml of bevacizumab. The HMVEC cultures were treated with 0.125, 0.25, 0.50 and 1 mg/ml of bevacizumab or 1 mg/ml of immunoglobulin G (control). Mitochondrial function assessed by mitochondrial dehydrogenase activity (MDA) was determined using the WST-1 assay.

Results:

Bevacizumab doses of 0.125 to 1 mg/ml for 5 days did not significantly affect the MDA of ARPE-19 cells. Bevacizumab treatment at 0.125 and 0.25 mg/ml (clinical dose) did not significantly affect the MDA of R28 cells; however, 0.50 and 1 mg/ml doses significantly reduced the R28 cell mitochondrial function. All doses of bevacizumab significantly reduced the MDA of proliferating and non-proliferating HMVEC.

Conclusion:

Bevacizumab exposure for 5 days was safe at clinical doses in both ARPE-19 and R28 retinal neurosensory cells in culture. By contrast, bevacizumab exposure at all doses show a significant dose-dependent decrease in mitochondrial activity in both the proliferating and non-proliferating HMVEC in vitro. This suggests a selective action of bevacizumab on endothelial cells at clinical doses.