Age-related macular degeneration (AMD) is an age-related neurodegenerative eye disease characterized by degeneration and progressive death of retinal pigment epithelium (RPE) and photoreceptor cells. In recent years, as a new treatment for AMD, stem cell therapy has attracted wide attention in the field of AMD, and has become a current research hotspot. Although stem cell therapy carries risks such as increased incidence of cancer and immune rejection, it significantly promotes damaged photoreceptor cells and retinal cells by differentiating into RPE cells and other retinal cell types, as well as secreting neurotrophic factors and extracellular vesicles. In particular, the development of embryonic stem cell-derived RPE cells, its cryopreservation technology and the advancement of plasmid, adeno-associated virus, Sendai virus and other delivery technologies have laid a solid foundation for stem cell therapy of AMD. As a new method to prevent retinal damage and photoreceptor degeneration, stem cell neuroprotective therapy has shown great potential, and with the continuous maturity and improvement of these technologies, stem cell therapy is expected to provide new ideas for the prevention and treatment of AMD in the future.
Age-related macular degeneration (AMD) is one of the leading irreversible causes of blindness in China. The pathogenesis of AMD is not fully understood at present. Under various stress conditions, cellular senescence is activated, characterized by telomere shortening, mitochondrial dysfunction, DNA damage, and the release of various senescence-related secretory phenotype factors. Senescence is implicated in the pathogenesis of AMD through multiple pathways, contributing to chronic inflammation and the onset and progression of AMD. Mechanisms such as oxidative stress, lipofuscin, β amyloid protein and the membrane attack complex have become hotspots of study in the pathogenesis of AMD. The cyclic guanosine phosphate - adenosine synthase - interferon stimulating factor synthase-stimulator of interferon gene pathway has emerged as a critical signaling pathway in the early development of AMD, providing direction for further research on AMD. Currently, senolytics, selective agents targeting the induction of senescent cell apoptosis, show significant potential in the treatment of AMD. The integration of new technologies with cellular senescence may offer a novel approach to AMD treatment, and intervening in the AMD treatment through anti-cellular senescence pathways holds promising prospects.
Vascular endothelial growth factor (VEGF) is a multifunctional factor that promotes blood vessel formation and increases vascular permeability. Its abnormal elevation plays a key role in common retinal diseases such as wet age-related macular degeneration and diabetic macular edema. Anti-VEGF therapy can inhibit angiogenesis, reduce vascular leakage and edema, thereby delaying disease progression and stabilizing or improving vision. Currently, the clinical application of anti-VEGF drugs has achieved satisfactory therapeutic effects, but there are also issues such as high injection frequency, heavy economy burden, potential systemic side effects, and non-responsiveness. To address these issues, current research and development mainly aim on biosimilars, multi-target drugs, drug delivery systems, oral anti-VEGF drugs, and gene therapy. Some drugs have shown great potential and are expected to turn over a new leaf for anti-VEGF treatment in ophthalmology.
Purpose To decribe the prevalence of age related macular degeneration (AMD) in the population aged 50 and over in Doumen County of Gunagdong Province. Methods After randomized clustering sampling,all selected individuals were enumerated according to village residence register.Visual acuity were measured by illuminated EDTRS chart. The examination of eyelid,cornea,lens and fundus were also carried out.The diagnosis of AMD was made according to the criteria of National Academic Group of Fundus Diseases combining with the visual criteria of Framingham Eye Study. Results 5 324 indivduals were axamined with participating rate of 92.8%.The ove rall prevalence of AMD was 8.4%.The prevalence of 2.9%,7.8% and 12.9% was found in the age groups of 50-,60-,70- respectively.The prevalence of male and female was 8.5% and 8.4% respctively.5% of AMD eyes were blind and 49% were low vision. Conclusion The prevalence of AMD is hight and increased with aging,but not correlated with sex.AMD can cause severe visual impairment. (Chin J Ocul Fundus Dis,1998,14:122-124)
Age-related macular degeneration (AMD) is one of the leading causes of irreversible vision loss. There are two primary forms of AMD: exudative age-related macular degeneration (WAMD) and atrophic AMD (DAMD). While numerous medications are currently available for the treatment of WAMD, yielding significant therapeutic outcomes, effective treatments for DAMD remain scarce. Various animal studies and clinical trials on DAMD treatment have been conducted, focusing primarily on antioxidants, complement pathway inhibitors, mitochondrial protectors, visual cycle inhibitors, neuroprotectants, amphiphilic polymer-based drug delivery systems, cell therapy, photobiomodulation therapy, gene therapy, surgical interventions, and traditional Chinese medicine. Among these, antioxidant supplementation with vitamins and complement pathway inhibitor APL-2 and ACP have received Food and Drug Administration approval for the treatment of DAMD. With the continuous development of the medical field, the future will explore the treatment methods with little trauma, good efficacy and good patient compliance, and successfully achieve clinical transformation.
According to the best corrected visual acuity and the morphological changes of the macular fovea, responses to the neovascular age-related macular degeneration (nAMD) who receive anti-vascular endothelial growth factor (VEGF) therapy show large variability, including poor and non-responders. Various factors will be reviewed to account for poor and non-response to anti-VEGF therapy, such as the related susceptibility genes, factors related with the development of choroidal neovascularization and morphologic parameters, pharmacokinetics and tachyphylaxis. The future research should focus on comprehensive assessment of factors affecting the efficacy of anti-VEGF therapy to improve the therapeutic outcome of nAMD.
ObjectiveTo observe the multi-modal fundus imaging features of subretinal drusenoid deposit (SDD) in age-related macular degeneration (AMD), and observe image features. MethodsA prospective clinical study. From December 2019 to December 2023, 65 patients (104 eyes) with a diagnosis of AMD-SDD by spectral domain optical coherence tomography (SD-OCT) examination in Shandong Eye Hospital were included. All eyes were examined by best corrected visual acuity (BCVA), traditional color fundus photography (CFP), ultra-wide-angle scanning laser fundus imaging (UWF), multicolor scanning laser fundus imaging (MC) and SD-OCT. The standard MC images were obtained by using Spectralis HRA+OCT for MC examination. The multi-mode image characteristics of SDD were analyzed retrospectively. Area under curve (AUC) was used to evaluate the sensitivity and specificity of CFP, MC and UWF in detecting SDD. ResultsAmong 65 patients with SDD, 29 cases of males (52 eyes) and 36 cases of females (52 eyes) was included. There were 26 patients with unilateral SDD and 39 patients with bilateral SDD. The average age was (71.74±10.97) years. The early, middle and late stages of AMD were 31 (29.8%, 31/104), 24 (23.1%, 24/104), 49 (47.1%, 49/104) eyes, respectively. The SDD detected by CFP, MC and UWF was 76 (73.1%, 76/104), 94 (90.4%, 94/104), 96 (92.3%, 96/104) eyes. CFP showed that the edge of SDD in the macular area was blurred. UWF showed that the dot and the ribbon SDD were light yellow pale discrete deposits and light yellow interlaced network deposits respectively. MC showed the dot SDD had a strong yellow-green circular reflection, while the edge of the ribbon SDD was surrounded by a weak reflection, and the boundary was clear. SD-OCT showed that SDD had strong reflection signal, which was located between the retinal pigment epithelium layer and the photoreceptor cell layer. The dot SDD could break through the ellipsoid zone and caused slight uplift or interruption of the external membrane, showing a cone-like strong reflection signal. While the ribbon SDD showed a continuous "hill-like" protrusion, which hardly broke through ellipsoid zone. The sensitivity and specificity of CFP, MC and UWF for SDD were 73.1%, 90.4%, 92.3% and 61.1%, 94.4% and 83.3%, respectively. ConclusionsMC and UWF show high sensitivity and specificity in diagnosing AMD-SDD, which is superior to CFP. SD-OCT can effectively reveal the location and morphoLogical characteristics of SDD under retina.
Age-related macular degeneration (AMD) involves dysregulation of the innate immune response of complement and mononuclear phagocytes and abnormalities of local microglia. When microglia transition from a resting state to an active state, their metabolic pathway also changes, known as "metabolic reprogramming", and their glucose metabolic reprogramming is a key factor in the pathogenesis of AMD, involving multiple signaling pathways. Including phosphatidylinositol 3-kinase-serine threonine kinase-rapamycin target, adenylate activated protein kinase and hypoxia-inducing factor 1 pathway. These metabolic changes regulate the inflammatory response, energy supply, and neuroprotective functions of microglia. Therapeutic strategies to regulate the reprogramming of glucose metabolism in microglia have achieved initial results. Future studies should further explore the mechanisms of microglia metabolic regulation to develop new targeted drugs and intervene in the treatment of AMD through anti-cellular aging pathways.
With the tremendous progress in fundus imaging and histopathology over the past decade, the understanding of age-related macular degeneration (AMD) has taken a qualitative leap. AMD is defined as a progressive neurodegenerative disease of photoreceptors and retinal pigment epithelium (RPE) characterized by extracellular deposits under RPE and the retina, including drusen, basal laminar and linear deposits, and subretinal drusenoid deposits, that can evolve to atrophy of the retina, RPE and choroid and neovascularization in the choroid and/or retina. It is the leading cause of blindness and visual impairment in older populations, despite recent advances in treatments. AMD is a multifactorial disease with genetic and environmental factors including advanced age, smoking, high-fat diet, and cardiovascular disorder to enhance the disease susceptibility. The physiopathologic mechanism includes inflammatory processes (complement pathway dysregulation, inflammasome activation), intrinsic (e.g., photo-oxidation) and extrinsic oxidative insult to the retina, age-related metabolic impairment (mitochondrial, autophagic and endoplasmic reticulum stress). Autophagy dysfunction and local inflammation in aged RPE specially result in the extracellular deposits, cell death and AMD. Further investigation of the pathogenesis of AMD will provide with new therapeutic targets and strategy for prevention and treatment of the disease in the early stages.
Subtype classification of age-related macular degeneration (AMD) based on optical coherence tomography (OCT) images serves as an effective auxiliary tool for clinicians in diagnosing disease progression and formulating treatment plans. To improve the classification accuracy of AMD subtypes, this study proposes a keypoint-based, attention-enhanced residual network (KPA-ResNet). The proposed architecture adopts a 50-layer residual network (ResNet-50) as the backbone, preceded by a keypoint localization module based on heatmap regression to outline critical lesion regions. A two-dimensional relative self-attention mechanism is incorporated into convolutional layers to enhance the representation of key lesion areas. Furthermore, the network depth is appropriately increased and an improved residual module, ConvNeXt, is introduced to enable comprehensive extraction of high-dimensional features and enrich the detail of lesion boundary contours, ultimately achieving higher classification accuracy of AMD subtypes. Experimental results demonstrate that KPA-ResNet achieves significant improvements in overall classification accuracy compared with conventional convolutional neural networks. Specifically, for the wet AMD subtypes, the classification accuracies for inactive choroidal neovascularization (CNV) and active CNV reach 92.8% and 95.2%, respectively, representing substantial improvement over ResNet-50. These findings validate the superior performance of KPA-ResNet in AMD subtype classification tasks. This work provides a high-accuracy, generalizable network architecture for OCT-based AMD subtype classification and offers new insights into integrating attention mechanisms with convolutional neural networks in ophthalmic image analysis.