What is the purpose of photocoagulation? The purpose of photocoagulation is to prevent blindness. Studies have shown that blindness due to diabetic retinopathy can be avoided in more than 60% of eyes if treated with timely photocoagulation, especially if blood glucose is well controlled. Photocoagulation is recommended. How does photocoagulation work? Photocoagulation reduces the risk of hemorrhage and retinal detachment by creating a concentrated light spot on the retina, which reduces the substances that stimulate abnormal neovascularization. In addition, photocoagulation of the macula reduces macular edema. All of these can stop vision loss and even improve vision. Does photocoagulation often improve vision? No. The purpose of photocoagulation is to prevent blindness. The purpose of photocoagulation is to prevent blindness, and vision usually does not improve, and in most cases may decrease slightly. In addition, many patients may experience a transient blurring of vision for a few hours after photocoagulation, but then their vision returns. Occasionally, some patients with early diabetic macular degeneration may have improved vision after photocoagulation. It is important to emphasize that vision does not usually improve after photocoagulation for diabetic retinopathy. However, in the long run, because the retinopathy is controlled after photocoagulation, there is a possibility that the vision will not decrease anymore, i.e., the vision is indirectly preserved. How often should photocoagulation be performed? It is recommended to treat one eye at a time, alternating between treatments. Monocular whole retinal photocoagulation is usually done in 3 to 5 sessions of 10 to 20 minutes each, with periodic follow-ups and additional photocoagulation if needed. Treatment is divided into sessions to avoid producing too many spots in the retina at one time, too much photocoagulation can cause macular edema and temporary vision loss. Is the treatment painful? Usually not. Occasionally, there is eye pain and swelling or headache during or after treatment, which is more common in patients with repeat treatments. If needed, medications may be given to relieve pain. In addition, the patient should be prepared psychologically before treatment and cooperate well with the doctor. Can photocoagulation cure diabetic retinopathy? No, it cannot. The purpose of photocoagulation is to preserve vision as much as possible and to stop the lesion from getting worse. It does this by destroying the abnormal retina and stopping the formation of new blood vessels and fluid leaks. However, the disease still progresses, abnormal neovascularization and leakage can continue, and will need to be treated again. Therefore diabetic patients should be followed up regularly and further photocoagulation is necessary. Is photocoagulation always effective? No. Photocoagulation is effective in most patients, but not all. In some cases, bleeding can continue even after photocoagulation. Can laser treatment be done if an IOL is available? Yes. In patients with a posterior chamber IOL, the pupil can be sufficiently dilated and the fundus can be treated with photocoagulation.