Age-related macular degeneration

There are two types of age-related macular degeneration (AMD), the “wet” type with subretinal neovascularization and the “dry” type with map-like atrophy. The prognosis of “wet” AMD is poorer, and its prevention and treatment is a major focus of ophthalmic research. For a long time, there has been a lack of effective therapies for AMD. A few years ago, laser retinal photocoagulation (PDT) was developed to prevent vision loss in “wet” AMD. Photocoagulation reduces subretinal hemorrhage and prevents retinal pigment epithelium and neuroretinal detachment, retinal thickening, and secondary scarring of the central retina. However, the recurrence rate of subretinal neovascularization after treatment with retinal photocoagulation is high, and the therapeutic effect is unsatisfactory. In addition, clinical trials to prevent or delay AMD with antioxidant and zinc supplementation therapy have been completed. However, they are ineffective in the progression of early AMD lesions. In recent years, intravitreal injections of anti-vascular endothelial growth factor (VEGF) have proved to be effective in some patients with wet AMD. As a representative of such drugs, Lucentis has been approved for clinical use. Compared to placebo, Lucentis can improve vision by up to 33.8% in some patients. However, anti-VEGF therapies still have shortcomings: only one-third of patients treated with Lucentis can improve their vision, and about one-sixth of patients continue to lose their vision and become blind. These facts suggest that anti-VEGF strategies are not sufficient to treat all patients with wet AMD. In addition, Lucentis treatment is expensive and requires long-term, multiple injections. The above deficiencies need to be improved urgently, and solving these problems will be a hot topic in research about AMD. It is foreseeable that these problems will be solved in the next decade, and new effective AMD treatments that treat both the symptoms and the root causes will emerge.