Laser is one of the most important means of modern ophthalmology for the treatment of fundopathy. Due to its high brightness, good directionality, monochromaticity and good coherence, laser can accurately and precisely target fundus lesions and utilize its high energy to achieve the purpose of sealing retinal fissures, reducing retinal edema, promoting hemorrhage absorption, reducing retinal leakage and eliminating lesions such as neovascularization, so as to achieve the function of treating fundus diseases. Mechanism and indications of fundus laser therapy Retinal photocoagulation is to use laser thermal coagulation reaction to make retinal pigment epithelium, choroidal pigment, hemoglobin absorb laser energy and generate heat, causing tissue protein denaturation, coagulation, causing scar adhesion to retinal choroid, retinal neuroepithelium and pigment epithelium adhesion, to improve retinal circulation and oxygen supply, reduce leakage, reduce edema, prevent recurrent hemorrhage. The purpose of preventing recurrent hemorrhage. Applicable to: 1, various retinal vascular abnormalities, such as: retinal hemangioma, choroidal hemangioma, retinal neovascularization. Retinal vascular inflammatory or obstructive diseases. Such as: retinal vein periphlebitis, retinal vein obstruction. 3.Retinal vasculopathy caused by systemic diseases, such as diabetic retinopathy, hypertensive retinopathy caused by retinal microangioma, retinal neovascularization and hemorrhage. 4.Other eye diseases: dry retinal chorioretinopathy, macular chorioretinopathy, retinal degeneration, cleavage and detachment, centralized plasma retinal chorioretinopathy and so on. Fundus laser treatment of diabetic retinopathy Director Jia said, diabetic retinopathy has become one of the four major blinding diseases, diabetes than non-diabetic blindness 25 times, all diabetic patients, 50% to 62% of patients will have eye complications, and the longer the duration of the disease, the higher the rate of disease. Patients with diabetes 5 years later, the incidence of retinopathy is about 25%; 10 years later increased to 60%; 15 years later can be as high as 75% ~ 80%; 20 years after the incidence of more than 90%. Half of them will become blind. Blindness due to diabetic fundopathy is very difficult to recover from, so special emphasis should be placed on early detection of fundopathy and early intervention and treatment. Many people with diabetes do not require treatment, but rather regular follow-up. Some patients who develop fundopathy require urgent treatment to prevent the condition from worsening. Factors affecting diabetic retinopathy 1, the patient is younger, longer duration of diabetes and type 1 diabetes and insulin-dependent diabetes mellitus 2, blood glucose suddenly well controlled, can cause non-proliferative retinopathy temporary development, long-term control, can make its lesions delayed and slow development. 3, blood pressure can promote the development of sugar reticulum, increased diastolic blood pressure of sugar reticulum at a young age is a precursor to the development of sugar reticulum 4, gestation can accelerate the development of sugar reticulum, 5, renal disease, microalbumin is a precursor to the occurrence of proliferative sugar reticulum. 6, other factors, anemia, smoking and drinking can aggravate the development of sugar network. When diabetic retinopathy has occurred, systemic treatment can only slow down its development, and once the progression of proliferative lesions, systemic treatment is difficult to improve, so far there is still no sure effective drugs. Laser coagulation for diabetic retinopathy is the only surely effective method and is a symptomatic treatment. As photocoagulation destroys the photoreceptor cells and retinal pigment epithelial cells of the outer retina, which consume the most oxygen, the retina’s oxygen demand decreases and the level of metabolism is lowered. The thinning of the retina caused the oxygen from the choroid, which was originally supplied to the outer retina, to diffuse to the inner retina, increasing the partial pressure of oxygen in the inner retina, thus alleviating retinal hypoxia. In addition, after photocoagulation, retinal blood flow decreases, dilated blood vessels contract, autoregulation improves, and small arteries also contract, which reduces the intravascular and transmural pressure of capillaries and small veins, and vascular leakage decreases, thus retinal edema decreases, tissue ischemia and hypoxia are relieved, and neovascularization degenerates, thus preventing further development of retinopathy. Some people will have improved vision after treatment, most people will have no change in vision after treatment, and a few people will have decreased vision, but it is totally worthwhile to sacrifice part of your vision and field of view in order to control the progression of the disease and avoid total blindness. Laser treatment does not require cutting into the eye and can be performed on an outpatient basis. If retinopathy is diagnosed early, photocoagulation can prevent vision loss. In proliferative lesions, laser treatment can also reduce the chance of visual damage and prevent hemorrhage. The laser works only where it is fired, it is not radioactive and has no effect on the rest of the body. When the laser is used to treat an eye disease, it passes through the transparent cornea to the treatment site and does not harm any eye tissue not in the treatment site, and there is no restriction on general physical activity after a treatment. Successful treatment requires not only early diagnosis and early treatment, but also the active cooperation of the patient and dietary control. As for diabetic retinopathy, it may be asymptomatic. Therefore, diabetic patients should actively and effectively control diabetes, so that blood glucose is reduced to normal or near normal, and at the same time, blood pressure and blood lipids should be controlled. No smoking, no alcohol therefore advocate, oral medication or insulin therapy, strengthen physical exercise regular blood sugar checks, pay attention to diet, eat more vegetables. At least once every six months to receive fundus examination, the emergence of retinopathy and macular edema timely use of laser treatment. After the laser treatment is completed, regular and timely review should be conducted. Diabetic retinopathy is a serious threat to patients’ vision, but it is controllable and treatable. Ophthalmologists advise: strict control of blood sugar, prevention and treatment of diabetic complications, long-term regular follow-up, early and reasonable treatment. Fundus laser treatment of retinal vein occlusion Retinal vein occlusion is a relatively common fundus disease, the formation of the causes are mostly due to (a) vascular lesions: changes in the walls of the venous blood vessels, hypertension atherosclerosis. (ii) Alterations in blood rheology: enhanced platelet aggregation and release. Alterations in other components of the blood, such as increased red blood cells and platelets, increased plasma lipids and proteins. (iii) Vascular inflammation: mostly seen in young patients. This disease often causes visual impairment due to retinal edema, exudation, hemorrhage, capillary occlusion, neovascularization, and macular edema, and in severe cases, it can cause vitreous hemorrhage, retinal detachment, neovascular glaucoma, and other serious complications. This disease can be divided into two types: ischemic and non-ischemic retinal vein occlusion. Laser photocoagulation can destroy the retinal tissues that are still alive in the lesion area, in a state of hypoxia and with obvious metabolic disorders, reduce the production of neovascularization stimulating factors, prevent the formation of neovascularization in the fundus and iris, or promote the regression of neovascularization that has been formed. In patients with large capillary perfusion-free areas in the fundus, iris neovascularization often occurs in about three months, and once neovascularization occurs in the iris, neovascular glaucoma can progress to neovascular glaucoma in a few weeks. According to some statistics, the incidence rate of neovascular glaucoma in patients with ischemic retinal vein occlusion is as high as 60%. Therefore, timely and appropriate selection of laser photocoagulation treatment for patients with retinal vein occlusion can stop the progression of the lesion, promote the recovery of visual acuity, and reduce and prevent the occurrence of complications. Fundus laser treatment of choroidal neovascularization Choroidal neovascularization (CNV) is mostly seen in age-related macular degeneration, central exudative choroidal retinopathy, high myopia, traumatic choroidal rupture and so on. Choroidal neovascularization often involves the macula and causes severe visual impairment. Once choroidal neovascularization is formed in the clinic, drug treatment is often ineffective, and it is removed by surgery, but due to the complexity of the surgery, the result is not good. At present, laser photocoagulation is still one of the main methods to treat choroidal neovascularization, using choroidal pigment and retinal pigment epithelium to absorb the laser energy into heat, so that the choroidal neovascularization coagulation and necrosis; or stimulate retinal pigment epithelial cell proliferation, encircle, inhibit the growth of choroidal neovascularization, so for the choroidal neovascularization of the choroid with a clear border, proper laser photocoagulation treatment, you can shorten the course of the disease to a certain extent and protect vision. Fundus laser treatment for retinal detachment and degeneration In ophthalmology clinic, peripheral retinal degeneration, high myopia, trauma, vitreous traction and other reasons can cause retinal detachment or even retinal detachment, and it is especially important to prevent retinal detachment by treating it as early as possible. The thermal coagulation reaction produced by laser photocoagulation can cause retinal choroidal scar adhesion at the edges of retinal degeneration, lacunae and detachment to prevent further development of the lesion. In the absence of retinal detachment, this is known as a “dry” fissure. Laser treatment can prevent retinal detachment. Retinal fissures without retinal detachment usually occur in the peripheral part of the retina, due to the thinness of the retina in the peripheral part of the peripheral part of the retina, the blood vessels are scarce, the blood supply is poor, and a variety of degenerative changes are likely to occur. Especially the older heavy laborers should regularly check the fundus changes, early detection of the crack laser treatment can prevent the occurrence of retinal detachment, for high myopia more than 1,000 degrees of patients, the peripheral part of the retina appeared extensive degeneration, and the patient in the near future feel the flash in front of the eyes, the black shadow floating aggravated. If there is no significant improvement after drug treatment, prophylactic laser treatment should be carried out, which can photocoagulate the normal retina outside the degeneration area and build a dike around it to prevent retinal detachment from occurring. Before preparing for surgical treatment, young and middle-aged myopia patients should routinely check the fundus with dilated pupils. If obvious degenerative changes of the peripheral retina such as lattice-like degeneration, dendritic degeneration, cystic retinal thinning or retinal cracks are found, laser photocoagulation treatment should be carried out first, so that all kinds of risk factors can be eliminated in time, and retinal detachment can be effectively avoided to affect the visual acuity after the surgery.