Intravitreal injections of anti-vascular endothelial growth factor (anti-VEGF) drugs, including monoclonal antibodies (such as bevacizumab and ranibizumab) and fusion protein agents (such as aflibercept and conbercept) have been proven to be effective in the treatment of wet age-related macular degeneration (wAMD). However, there are still some patients with poor efficacy, such as no response to initial treatment or poor response, and even relapse during the course of treatment. In view of the different targets and molecular characteristics of anti-VEGF drugs, the switch of anti-VEGF drugs and the adjustment of delivery pattern, dosages and intervals have been the strategies to cope with the poor efficacy in clinic. However, there are some differences in the results of current studies. Overall, the recovery of retinal anatomical outcome achieves more benefits, and it is relatively difficult to improve visual acuity. To determine which regimen would get the biggest benefits, a large number of randomized controlled clinical trials and long study period will be needed.
Choroidal neovascularization (CNV) is the key characteristic of neovascular age-related macular degeneration (nAMD), and the effective therapy is intravitreal injection of anti-vascular endothelial growth factor (VEGF) agents based on clinical and basic research. In the meantime the challenge is how to further improve the inhibiting effect for CNV and visual function of anti-VEGF treatment on nAMD. The new strategy and drug delivery devices for anti-VEGF treatment will optimize the clinical scheme. From bench to bedside, the research on targeted treatment of angiogenesis brings the bloom of nAMD medical therapy.
Wet age-related macular degeneration (wAMD) is caused by choroidal neovascularization (CNV), which occurs when the choroidal new capillaries reach the RPE layer and photoreceptor cell layer through the ruptured Bruch membrane, leading to neovascularization bleeding, leakage, and scarring. In view of the important role of VEGF in the development of CNV, targeted therapy with various intraocular anti-VEGF drugs is the first-line treatment for wAMD. However, the efficacy of anti-VEGF drugs in the treatment of wAMD is affected by a variety of factors, and some patients still have problems such as unresponsiveness, drug resistence, tachyphylaxis, long-term repeated injections, and severe adverse effects. It is the direction of future researches to deeply explore the physiological and pathological process of wAMD, find the cause of CNV formation, and seek better therapies.
Objective To investigate the correlation between the vitreomacular adhesion (VMA) and exudative age-related macular degeneration (AMD). Methods A literature research was performed in PubMed, EMbase, Cochrane Library, CNKI and Wanfang database from January 2000 to December 2016. Case-control studies on the relationship between VMA or posterior vitreous detachment and exudative AMD were included in this analysis. Literature screening and data extraction were performed according to inclusion and exclusion criteria. The qualities of the literatures were evaluated according to the Newcastle-Ottawa Scale (NOS). Seven literatures were selected into meta-analysis. The NOS score was 9 points in 1 article, 8 scores in 4 articles, 7 points in 2 articles. A total of 947 eyes with exudative AMD, 638 eyes with dry AMD, and 618 eyes with controls were included. The correlation between exudative AMD and VMA were analyzed using the software Review manager 5.3. Results The prevalence of VMA in exudative AMD eyes was higher than that in controls [odds ratio (OR)=2.14, 95% confidence interval (CI)=1.19 - 3.84, P=0.010] and dry AMD eyes (OR=2.24, 95%CI=1.24 - 4.03, P=0.007). There was no difference in PVD prevalence among exudative AMD eyes, dry AMD eyes (OR=0.44, 95%CI=0.16 - 1.20, P=0.110) and controls (OR=0.70, 95%CI=0.41 - 1.18, P=0.180). Conclusion There is correlation between VMA and exudative AMD.
Anti-vascular endothelial growth factor (VEGF) drugs, including monoclonal antibodies (such as bevacizumab and ranibizumab) and fusion protein agents (such as aflibercept and conbercept) have been clinically proven to be effective to treat exudative age-related macular degeneration AMD). However, there are still some patients do not or poorly respond to the initial anti-VEGF agents, usually after several injections, ophthalmologists may switch to another anti-VEGF agent. In general, switching of anti-VEGF agent is considered for recurrent AMD, AMD resistance to anti-VEGF treatments. Current switching protocols include the replacement of monoclonal antibodies with fusion protein agents, the replacement of fusion protein agents with monoclonal antibodies, the substitution of one monoclonal antibody with another one, and the replacement of monoclonal antibodies with fusion protein agents and switching back with monoclonal antibodies. However, current researches on the switching of anti-VEGF drugs for exudative AMD are mostly retrospective and single-arm studies, and there are some differences in the results of different studies. Therefore, for patients with exudative AMD who do not respond to or respond poorly to anti-VEGF drugs, the efficacy of switching of anti-VEGF drugs is uncertain right now. Switching of anti-VEGF agents may improve the retinal anatomical outcome of the affected eye but may not necessarily improve visual acuity. Thus it is an option in the clinical practice to treat AMD. To determine the benefits of above mentioned switching regimens, randomized controlled clinical trials with large sample number and long study period will be needed.
ObjectiveTo observe the clinical efficiency of intravitreal Conbercept on exudative age-related macular degeneration (eAMD). MethodsThis is an open and prospective study without control trial. Twenty eyes from 20 patients (19 males and 1 female) with eAMD diagnosed by fundus fluorescein angiography (FFA) and indocyanine green angiography (ICGA) were enrolled in this study. Before the injection, best-corrected visual acuity (BCVA) of early treatment of diabetic retinopathy study (ETDRS), non-contact tonometer, ophthalmoscope, fundus photography, fundus fluorescein angiograph (FFA), indocyanine green angiography (ICGA) and optical coherence tomography (OCT) were examined. The initial average letters of ETDRS acuity were 41.20±22.61, range from 8 to 80. The initial average central retina thickness (CRT) was (345.25±131.96) μm, range from 152 to 770 μm.All affected eyes were treated with intravitreal conbercept 0.05 ml (10 mg/ml). The patients were followed up for 6 to 9 months, with the mean time of (7.35±0.99) months.The BCVA, CRT after treatment were compared with baseline using paired t-test. ResultsDuring the 1, 3, 6, 12 months after treatment and the latest follow up, the mean BCVA were all improved with statistically significant difference (t=5.85, 7.09, 7.44, 7.25; P < 0.05). At 1 month ater treatment, the mean BCVA was obviously improved in 6 eyes (30%), improved in 8 eyes (40%), stable in 6 eyes (30%). At latest follow up, the mean BCVA was obviously improved in 6 eyes (30%), improved in 9 eyes (45%), stable in 5 eyes (25%). During the 1, 3, 6, 12 months after treatment and the latest follow up, the mean CRT were all decreased with statistically significant difference (t=3.34, 3.78, 3.47, 3.44; P < 0.05). At latest follow up, the leakage in macula lutea disappeared in 6 eyes (30%), decreased in 11 eyes (55%) and increased in 3 eyes (15%). No adverse events such as secondary retinal detachment or endoophthalmitis were found during the follow-up duration. ConclusionIntravitreal conbercept is a safe and effective approach for eAMD, may improve visual acuity, exudation and macular edema.
ObjectiveTo observe the effects of repeated intravitreal injections of anti-vascular endothelial growth factor (VEGF) drugs on vitreous macular interface (VMI) in patients with exudative age-related macular degeneration (AMD).MethodsRetrospective study. Thirty-four exudative AMD patients who treated with intravitreal anti-VEGF drugs were included in this study. There were 26 males and 8 females. The age ranged from 50 to 80 years, with the average of (62.8±8.35) years. The eyes with at least 6 treatments during the 1-year follow-up were taken as the study eyes, and the eyes with no anti-VEGF drug treatment were the control eyes. Optical coherence tomography (OCT) examination was used to observe the VMI status of both eyes before treatment. Vitreous macular adhesion (VMA), macular epiretinal membrane (MEM), and complete vitreous detachment (C-PVD) were defined as abnormalities in VMI. The VMA was classified as focal (≤1500 μm) and broad (＞1500 μm) depending on the diameter of the vitreous and macular adhesions on the OCT images. Before treatment, there were 12 eyes with abnormal VMI in study eyes, including 8 eyes with broad VMA, 3 eyes with focal VMA, and 1 eye with MEM; 12 eyes with abnormal VMI in control eyes: broad VMA in 7 eyes, focal VMA in 2 eyes, C-PVD in 2 eyes, and MEM in 1 eye. The average follow-up time after treatment was 16.4 months. During the follow-up period, OCT was performed monthly in a follow-up mode. Comparing the changes on VMI between before and after treatment in both eyes of patients, respectively. The chi-square test was used to compare the difference on VMI. Because the number of samples was ＜40, Fisher's exact test was used for the analysis.ResultsAt the final follow-up, 12 eyes with abnormal VMI in the study eyes, including 5 eyes with broad VMA, 2 eyes with focal VMA, 3 eyes with C-PVD, and 2 eyes with MEM. There were 6 eyes altered comparing with baseline. In the control eyes, there were 13 eyes with abnormal VMI, including 5 eyes with broad VMA, 7 eyes with C-PVD, and 1 eye with MEM. A total of 6 eyes changed on VMI comparing with baseline. At the final follow-up, there was no significant difference on VMI changes between the study eyes and its corresponding control eyes (P=0.053). In all eyes, a total of 4 eyes changed from focal VMA to C-PVD at the final follow-up, accounting for 80.0% of the total focal VMA; 3 eyes changed from broad VMA to C-PVD, accounting for 21.4% of the total broad VMA.ConclusionsRepeated anti-VEGF treatment has little effect on VMI. Regardless of anti-VEGF therapy, eyes with focal VMA appears to be more prone to C-PVD than the broad one.
Epigenetics has been very hot in the research of biomedicine. In addition to genetic factors, the occurrence of a disease is also influenced by environmental factors. Retinal vascular diseases are a type of irreversible blind eye disease, such as age-related macular degeneration and diabetic retinopathy. The retinal vessel changes are the major features of retinal vascular diseases, which are the result of interaction of multiple environmental factors and genes. Epigenetic modification mainly includes DNA methylation, histone modification, and non-coding RNA regulation. Epigenetic mechanisms mediate the effects of environmental factors on genes related to retinal vascular diseases, and affect the eventual development of the diseases. Therefore, ophthalmologists should keep eyes close on the role of epigenetics in retinal vascular diseases, track the progress of epigenetic methods in the treatment of retinal vascular diseases, and pay attention to the application prospects of epigenetics. Finding the epigenetic regulators of these diseases can not only deepen the understanding of the pathological mechanism of these diseases, but also provide new ideas for the diagnosis and treatment of these diseases.
ObjectiveTo observe the short-term effects of intravitreal injection of aflibercept (IVA) for initial treatment and dressing change on exudative age-related macular degeneration (eAMD). MethodsA retrospective clinical study. From June 2018 to February 2021, forty-nine eAMD eyes of 38 patients who underwent IVA treatment in Department of Ophthalmology of Central Theater Command Hospital of People’s Liberation Army were included in the study. Among them, there were 24 males with 29 eyes and 14 females with 20 eyes; the average age was 66.82±8.71 years. All affected eyes were treated with IVA. The initial loading dose was 2.0 mg, which was injected once a month for 3 consecutive months, followed by monthly review and treatment as needed. Of the 49 eyes, 26 eyes were initially treated (initial treatment group), they were diagnosed within 3 months of the first onset and followed by IVA treatment, and no intraocular drugs and surgery were performed from the onset to the first diagnosis. Twenty-three eyes were treated with drug exchange therapy (dressing change group), they received intravitreal injection of ranibizumab and/or conbercept more than 4 times 6 months before the replacement therapy, during which there was persistent interlaminar cystoid edema and/or subretinal fluid (SRF) in the macular area and no improvement in pigment epithelial detachment (PED). Before IVA treatment, there were no statistically significant differences in the best corrected visual acuity (BCVA), foveal thickness (CMT), PED height (PEDH), and PED volume (PEDV) of the two groups of eyes before IVA treatment (P＞0.05). The same equipment and methods as before treatment were used for related examinations, and the changes of BCVA, CMT, PEDH, PEDV and complications of the two groups of eyes were recorded in 1, 3, and 6 months after treatment. The comparison of BCVA, CMT, PEDH, and PEDV between the two groups were used repeated measures analysis of variance. ResultsSix months after treatment, the number of IVA injections in the eyes of the initial treatment group and dressing change group were 4.15±0.73 and 4.39±0.72 times, respectively, and the difference was not statistically significant (t=−1.141, P=0.260). The BCVA, CMT, PEDH, and PEDV of the the initial treatment group (F=5.345, 22.995, 6.764, 5.425) and the dressing change group (F=12.519, 15.576, 8.843, 9.406) were significantly improved compared before treatment with 1, 3, and 6 months. All were statistically significant (P＜0.05). There was no significant difference in BCVA, CMT, PEDH, and PEDV between the initial treatment group and the dressing group at each time point after treatment (F=1.741, 0.069, 0.876, 3.455; P＞0.05). During the follow-up period, none of the affected eyes had complications such as persistent intraocular pressure increase, endophthalmitis, and retinal pigment epithelial tear. ConclusionsIVA can improve eyesight of patients with eAMD and reduce CMT, PEDH, and PEDV. The initial treatment and dressing change have the same effect.
Exudative or wet age-related macular degeneration (AMD) is characterized by the progressive growth of choroidal neovascularization (CNV). Anti-vascular endothelial growth factor (VEGF) drugs have been used in the control of the development of CNV and vision improvement, but there are still defects like frequent injections, drug resistance and so on. Radiotherapy can deactivate local inflammatory cell populations, and make CNV unstable in the absence of pericytes and VEGF stimulation, which induce apoptosis of the vascular endothelial cells. Therefore, radiotherapy is considered as a potential adjuvant treatment of anti-VEGF therapy. The current clinical approaches include epimacular brachytherapy (EMBT) and long-range stereotactic radiotherapy (SRT). SRT may be a preferred adjuvant treatment for patients receiving anti-VEGF therapy. Knowing the progress of radiotherapy for the treatment of exudative AMD may help us to fully understand the pathogenesis of wAMD in China