The incidence of age-related macular degeneration (AMD) is rapidly increasing in Western developed countries and has become the most serious blinding eye disease in the age group of 50 years or older with loss of central vision, and the incidence increases with age. Epidemiological studies in some areas of China suggest that the incidence of the disease is also increasing.
I. Etiology
The occurrence of AMD is associated with genetics, environmental factors such as long-term exposure to ultraviolet light, environmental pollution, smoking, race, obesity, Jinxing Wang of the General Hospital of Ningxia Medical University Ophthalmology
Family history, and decreasing blood antioxidant levels are related to other factors.
II. Typing and examination
AMD involves choroidal capillaries, Bruch’s membrane and retinal pigment epithelium (RPE), resulting in loss of vision due to extensive visual cell dysfunction and death. formation. AMD is mainly divided into dry type and wet type, and the course of the disease is divided into early, middle and late stages. Dry AMD occurs when the photoreceptor cells in the macula of the affected eye are slowly destroyed and the central vision is gradually blurred. Vitreous warts are one of the most common early signs of dry AMD. When there is abnormal growth of new blood vessels behind the retina in the macula, it is called wet AMD, these new blood vessels are very fragile and prone to hemorrhage and fluid leakage, these hemorrhage and fluid leakage will lead to edema bulge in the macula, and damage to the macula will occur soon. As wet AMD progresses, there is a rapid loss of central vision. Wet AMD is an advanced form of AMD and is more severe than dry AMD. An early symptom of wet AMD is distorted vision. The main examination methods are Amsler table, direct and indirect fundoscopy, 90D slit lamp indirect fundoscopy, fundus photography, FFA, ICGA, OCT multifocal ERG, computerized visual field meter and other examination instruments, and other tests.
III. Treatment
There is no treatment for dry AMD that can prevent vision loss. However, studies have found that taking a special high dose of a synthetic formulation of antioxidants and zinc is effective in reducing the risk of advanced AMD and associated vision loss. Wet AMD treatment options include.
1. CNV laser therapy: The heat energy generated by the laser is used to destroy the abnormal neovascularization in the macula, with the disadvantage that damage is also produced to the nearby normal tissues, and visual function will be greatly affected with recurrence. 2. Trans-pupillary thermotherapy (TTT): Using infrared light to irradiate the macular lesion area with weak energy to slightly warm up the lesion area, so as to achieve the purpose of shrinking the abnormal new blood vessels. The cost of this therapy is low, but there is some damage to the local normal tissue, and the efficacy is not very satisfactory. Photodynamic therapy (PDT) is used to treat neovascular AMD, especially the central concave type, because it can selectively treat the lesioned area. Photodynamic therapy uses the accumulation, retention and proliferation of photosensitizers in the tissues to produce reactive oxygen species and free radicals when the photosensitizer molecules are activated by the appropriate wavelength of light, resulting in cellular damage. The advantage of ocular PDT is its inherent dual selectivity: the photosensitizer is localized to the target tissue and irradiates a specific area. The new generation of photosensitizers is Benzoporphyrin Derivative (BPD), and Verteporfin (Visudyne), which is now commonly used clinically, has the effect of enhancing the stability of visual function.
4. Anti-neovascular therapy The main drugs are Ranibizumab (Lucentis) and Bevacizumab (Avastin), anti-VEGF drugs combined with PDT can not only close CNV, improve the efficacy, but also reduce the recurrence of CNV, reduce the number of PDT and intraocular injection, reduce the risk of treatment, especially the risk of intraocular infection caused by intraocular injection. The risk of intraocular infection caused by intraocular injection is reduced.
5. Surgical treatment: For example, subretinal neovascular membrane excision surgery is risky and the efficacy is not exact. Retinal transplantation: It is still in the research stage. Macular translocation surgery requires higher surgical technique, more intraoperative and postoperative complications, and higher surgical risks. Post-operative vision, because the macular area has been transposed, is bound to lead to binocular confusion or diplopia, so it is necessary to perform eye muscle surgery again to correct the eye position. V. Prevention: 1. If someone in the family has AMD, then family members over 50 years old should have regular fundus examination. 2. Since AMD may be related to long-term UV exposure, wear sunglasses when going out in strong sunlight. 3. Since vegetables and fruits contain a lot of antioxidant substances such as trace elements, multivitamins, lutein, etc., it is recommended to eat more vegetables and fruits.
Therefore, it is recommended to eat more vegetables and fruits. Fish contains a large amount of unsaturated acids and has strong antioxidant power, so it is recommended to eat more. 4. Take a variety of health supplements with antioxidant power, especially lutein and zeaxanthin. Multicenter
Clinical studies have shown that long-term use of eye care drugs containing lutein, trace elements of zinc and multivitamins, unsaturated fatty acids in line with
The use of long-term eye care drugs containing lutein, zinc, multivitamins and saturated fatty acids can help prevent the development of AMD.
5. Actively quit smoking, prevent hypertension and hyperlipidemia, eat less oily food, and strengthen exercise