Diabetic retinopathy (DR) is the most common microvascular complication of diabetes and the leading cause of visual impairment in the working-age population in the Western world. Diabetic macular ...oedema (DME) is one of the major complications of DR. Therapy with intravitreal injections of anti-vascular endothelial growth factor (anti-VEGF) drugs has become the gold standard treatment for DR and its complications. However, these drugs have no effect on the pathogenesis of DR and must be administered frequently via invasive intravitreal injections over many years. Thus, there is a pressing need to develop new therapeutic strategies to improve the treatment of this devastating disease. Indeed, an increasing volume of data supports the role of the inflammatory process in the pathogenesis of DR itself and its complications, including both increased retinal vascular permeability and neovascularization. Inflammation may also contribute to retinal neurodegeneration. Evidence that low-grade inflammation plays a critical role in the pathogenesis of DME has opened up new pathways and targets for the development of improved treatments. Anti-inflammatory compounds such as intravitreal glucocorticoids, topical non-steroidal anti-inflammatory drugs (NSAIDs), antioxidants, inflammatory molecule inhibitors, renin–angiotensin system (RAS) blockers and natural anti-inflammatory therapies may all be considered to reduce the rate of administration of antineovascularization agents in the treatment of DR. This report describes the current state of knowledge of the potential role of anti-inflammatory drugs in controlling the onset and evolution of DR and DME.
Vascular endothelial growth factor (VEGF) is a naturally occurring glycoprotein in the body that acts as a growth factor for endothelial cells. It regulates angiogenesis, enhances vascular ...permeability, and plays a major role in wet age-related macular degeneration. The consistent association between choroidal neovascularization and increased VEGF expression provides a strong reason for exploring the therapeutic potential of anti-VEGF agents in the treatment of this disorder. Blockade of VEGF activity is currently the most effective strategy for arresting choroidal angiogenesis and reducing vascular permeability, which is frequently the main cause of visual acuity deterioration. In recent years, a number of other molecules have been developed to increase the efficacy and to prolong the durability of the anti-VEGF effect. Aflibercept (EYLEA®; Regeneron Pharmaceutical Inc and Bayer), also named VEGF Trap-eye, is the most recent member of the anti-VEGF armamentarium that was approved by the US Food and Drug Administration in November 2011. Because of its high binding affinity and long duration of action, this drug is considered to be a promising clinically proven anti-VEGF agent for the treatment of wet maculopathy.
This article reviews the current literature and clinical trial data regarding the efficacy and the pharmacological properties of VEGF-Trap eye and describes the possible advantages of its use over the currently used "older" anti-VEGF drugs.
For this review, a search of PubMed from January 1989 to May 2013 was performed using the following terms (or combination of terms): vascular endothelial growth factors, VEGF, age-related macular degeneration, VEGF-Trap eye in wet AMD, VEGF-Trap eye in diabetic retinopathy, VEGF-Trap eye in retinal vein occlusions, aflibercept. Studies were limited to those published in English.
Two Phase III clinical trials, VEGF Trap-eye Investigation of Efficacy and Safety in Wet AMD (VIEW) 1 and 2, comparing VEGF Trap-eye to ranibizumab demonstrated the noninferiority of this novel compound. The clinical equivalence of this compound against ranibizumab is maintained even when the injections are administered at 8-week intervals, which indicates the potential to reduce the risk of monthly intravitreal injections and the burden of monthly monitoring.
Purpose
To evaluate the effect of internal limiting membrane (ILM) peeling during vitrectomy for nontractional diabetic macular edema.
Methods
PUBMED, MEDLINE and CENTRAL were reviewed using the ...following terms (or combination of terms): diabetic macular edema, nontractional diabetic macular edema, internal limiting membrane peeling, vitrectomy, Müller cells. Randomized and nonrandomized studies were included. The eligible studies compared anatomical and functional outcomes of vitrectomy with or without ILM peeling for tractional and nontractional diabetic macular edema. Postoperative best-corrected visual acuity and central macular thickness were considered, respectively, the primary and secondary outcomes. Meta-analysis on mean differences between vitrectomy with and without ILM peeling was performed using inverse variance method in random effects.
Results
Four studies with 672 patients were eligible for analysis. No significant difference was found between postoperative best-corrected visual acuity or best-corrected visual acuity change of ILM peeling group compared with nonpeeling group. There was no significant difference in postoperative central macular thickness and central macular thickness reduction between the two groups.
Conclusions
The visual acuity outcomes in patients affected by nontractional diabetic macular edema using pars plana vitrectomy with ILM peeling versus no ILM peeling were not significantly different. A larger prospective and randomized study would be necessary.
Triamcinolone acetonide (TA) is one of the first pharmacologic compounds evaluated for the treatment of choroidal neovascularization (CNV) secondary to age-related macular degeneration (AMD). The ...most important effects of TA consist in the stabilisation of the blood-retinal barrier and the down-regulation of inflammation. TA also has anti-angiogenic and anti-fibrotic properties. The peculiar characteristic of being well tolerated by ocular tissues and the capability to remain active for many months after a single intravitreal injection, make this drug a safe and effective alternative. In the past decade, intravitreal injection of TA (IVTA) has emerged as a useful treatment of several ocular diseases such as uveitis, macular edema secondary to retinal vasculature disease, neovascularisation and vitreoretinopathy. In this paper, we review all the available evidence of its use in AMD as mono-therapy or in combination with other treatments, and we discuss which role TA will play in the treatment of AMD in the future. The first experiences with IVTA as monotherapy for the treatment of exudative AMD reported a positive outcome in transiently reducing the leakage from CNV. However, in the long-term follow-up, IVTA as monotherapy had no effect on the risk of severe visual acuity loss, despite a significant anti-angiogenic effect found 3 months after the treatment. Consequently, studies using the combination of IVTA and photodynamic therapy (PDT), which acts synergistically, were performed. They reported to improve vision and to reduce the number of re-treatments with PDT. A large number of publications confirmed the positive synergic role of combining TA and PDT (therapies) for the treatment of all types of CNV: classic or predominantly classic, occult or minimally classic and RAP (Retinal Angiomatous Proliferation) lesions. The advantages registered with the use of IVTA plus PDT compared to PDT alone were partially limited by the side effects, such as the rapid evolution of cataract. Nevertheless, cataract surgery may stimulate the development of CNV (result in stimulating CNV). However, in large, randomized, clinical trials on combination therapy of TA and PDT, visual acuity failed to show an improvement, even though the lesion size and subretinal fluid had decreased, compared to controls treated with PDT alone. Some authors reported an increased risk of developing macular atrophy after the combination therapy with IVTA and PDT. Reduction of the PDT fluence rate in association with the use of steroids resulted in reducing the risk of macular atrophy and in a better visual acuity outcome. The introduction of anti-VEGF-based drugs has revolutionized the treatment of AMD and has replaced all the previous therapies used for CNV. Visual improvement becomes an expectation in a higher proportion of patients, previously limited to minimizing vision loss. Anti-VEGF therapy also resulted in superior visual improvement compared to all types of combination therapy with IVT and PDT. Nevertheless, anti-VEGF monotherapy also has many limitations due to the need of repetitive treatments, increased costs and tachyphylaxis. Treatment regimens involving TA in combination therapy with anti-VEGF and PDT may preserve benefits for substantially longer periods. A question remains open on whether a combination treatment with anti-VEGF, triamcinolone and/or PDT may be a treatment option in patients with exudative AMD, by offering, with one cycle of therapy, functional VA benefits comparable to those observed with continued monthly anti-VEGF therapy. Further trials, of higher scientific significance, are needed to study the potential of these treatment options.
Abstract Aim This study compared systemic and intraocular concentrations of erythropoietin (EPO) and vascular endothelial growth factor (VEGF) in patients with type 2 diabetes (T2D) and proliferative ...diabetic retinopathy (PDR) with levels in patients without diabetes, and looked for possible correlations between the concentrations found and other variables analyzed. Methods Concentrations of EPO and VEGF were measured in the aqueous and vitreous humours and serum of patients undergoing vitrectomy for PDR (33 patients) or for macular holes or puckers (20 control patients). EPO was assayed by radioimmunoassay, with a lower limit of detection (LOD) of 1.0 mIU/mL. VEGF was assayed using enzyme-linked immunosorbent assay (ELISA), with a lower LOD of 10.0 pg/mL. Results EPO concentrations in serum did not differ significantly between the two groups, whereas EPO in vitreous and aqueous were higher in diabetic than in non-diabetic patients. VEGF in serum was lower in diabetic patients than in non-diabetics; conversely, VEGF concentrations in vitreous were significantly higher in diabetic patients. A direct correlation was found between vitreous and aqueous EPO concentrations, and between vitreous EPO and blood glucose concentrations. A significant, negative correlation between vitreous EPO concentration and age was also recorded. Conclusion High EPO concentrations in the vitreous of patients with PDR and its correlation with blood glucose suggest that EPO could play a role in the pathogenesis of PDR. All possible factors affecting serum and ocular concentrations of EPO and VEGF should be determined to identify compounds able to prevent and control this serious microvascular complication of diabetes.
Central serous chorioretinopathy (CSC) is a common retina disease and has a relative high recurrence rate, etiology, and pathogenesis of which remains largely ambiguous. The effects on the retina are ...usually self-limited, although some people are left with permanent vision loss due to progressive and irreversible photoreceptor damage or retinal pigment epithelium atrophy. There have been a number of interventions used in CSC, including, but not limited to, laser treatment, photodynamic therapy (PDT), intravitreal injection of anti-vascular endothelial growth factor agents, and subthreshold lasers. It is not clear whether there is a clinically important benefit to treating acute CSC, which often resolves spontaneously as part of its natural history. Of the interventions studied to date, PDT and micropulse laser treatment appear the most promising. .
Abstract Surgical management of an idiopathic macular hole consists of vitrectomy to release vitreofoveal traction and intraocular tamponade to flatten and reappose the hole’s edges. The intentional ...atraumatic removal of the internal limiting membrane has been proposed as cost-effective option in macular hole surgery. The internal limiting membrane contributes to tangential traction at the edges of the hole and acts as a platform on which glial cells proliferate. Removal of the internal limiting membrane increases the elasticity of the denuded macula and improves the anatomical success rate; however, the visual consequences of this surgical maneuver are still not fully known. We discuss the beneficial and adverse effects associated with internal limiting membrane peeling in macular hole surgery, highlighting the internal limiting membrane’s role in macular hole etiology and pathogenesis and the anatomical and functional findings after its removal.
The wet form of age related macular degeneration (AMD), known also as exudative or neovascular, is characterized by the formation of a pathological choroidal neovascular membrane (CNV) responsible ...for most cases of severe blindness. Vascular endothelial growth factor (VEGF) is a homodimeric glycoprotein acting as a growth factor selective for endothelial cells; it regulates angiogenesis and enhances vascular permeability and plays a leading role in this disorder. The consistent association between CNV and increased VEGF-A expression provides a strong reason for exploring the therapeutic potential of anti-VEGF agents in the treatment of neovascular AMD. The importance of VEGF for the development of AMD-related CNV has led to the development of a strategy able to block its pathologic effects. The rationale is that a blockade of VEGF actions could be effective in arresting choroidal angiogenesis and also reducing the vascular permeability, which is frequently the main cause of visual acuity deterioration. However, VEGF has also important functions in vascular physiology. The effects of anti-VEGF therapy may inhibit these functions. Herein we report the systemic adverse events secondary to intravitreal administration of these compounds i.e. the main cardiovascular effects (thrombosis, hemorrhage, hypertension, proteinuria), as well as the less frequent cerebrovascular accidents, myocardial infarction, transient ischemic attacks, deep vein thrombosis, pulmonary embolism and thrombophlebitis.
The aim of this study was to evaluate whether indomethacin eye drops and intravitreal ranibizumab (IVR) injections would provide additional benefit over ranibizumab alone in the treatment of ...choroidal neovascularization (CNV).
This was a randomized, prospective pilot study of eyes with new-onset CNV. Fifty-eight patients were randomized 1:1 into a ranibizumab monotherapy (RM) group and a ranibizumab plus indomethacin (RI) group. All patients received monthly 0.5 mg IVR injections for 3 months, followed by monthly injections administered as needed. RI group patients also self-administered one drop of 0.5% indomethacin three times a day for 12 months. All patients were followed up for 12 months.
At 12 months, both groups showed significant improvement in best-corrected visual acuity (BCVA) and central retinal thickness (CRT). The mean BCVA change from baseline to 12 months was -0.12±0.04 LogMAR and -0.20±0.04 LogMAR in the RM and RI groups, respectively, with the degree of change being significantly different between the two groups (
=0.04). At 12 months, the mean CRT in the RM group (316±41.2 µm) was significantly higher than that in the RI group (287±31.5 µm;
=0.004). The mean required number of IVR injections was 7.38±0.78 and 6.34±0.67 in the RM and RI groups, respectively (
<0.001).
Compared to IVR monotherapy, combination therapy with indomethacin eye drops and IVR provides superior anatomical and visual outcomes in patients with naive CNV lesions. Moreover, topical indomethacin might reduce the frequency of IVR injections, which is very beneficial considering the chronic and expensive nature of IVR therapy.
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