Diabetes patients cannot use sugars properly. High blood-sugar levels can damage the blood vessels in the nerve layer behind the eye and in the vision. This type of damage in the nerve layer of the eye is called diabetic retinopathy.
Types of diabetic retinopathy
There are two types of diabetic retinopathy: non-proliferative diabetic retinopathy. Non-proliferative diabetic retinopathy shows an early stage of diabetic retinopathy and is also known as onset retinopathy. At this stage, blood or fluid leakage from small blood vessels in the nerve layer of the eye occurs. The infiltrating fluid causes the nerve layer to swell and the formation of deposits called exudates. Most diabetic patients have mild onset diabetic retinopathy, which usually does not affect vision. If vision reduction occurs, it is usually due to macular edema and / or macular ischemia. Macular edema is the sharp area of the eye, known as the yellow spot, and the center of the nerve layer in the center of the small area called the macula is swelling or thickening. Swelling is caused by leakage of blood vessels of the nerve layer. This is the most common cause of visual loss in diabetic patients. The loss of vision may be mild or severe, but even in the most severe cases, environmental vision is maintained.
Macular ischemia occurs when small blood vessels are clogged. Because macula cannot be fed with blood to maintain its normal functioning, vision becomes blurred. When abnormal new vessels on the nerve or nerve layer (retina) begin to form (neovascularization), they are called proliferative diabetic retinopathy. The main cause of proliferative diabetic retinopathy is the blockage of multiple retinal blood vessels and inadequate feeding of the retina. The retina responds to the formation of new vessels and their feeding through them.
But these new abnormal vessels cannot provide normal blood flow. Occasionally, leaks and bleeding from them, and they are accompanied by scar tissue, so that the retina wrinkles and detachment occurs. In proliferative diabetic retinopathy, vision loss is more severe, because central and environmental vision is affected. The best way to prevent them is laser treatment in the early period. Proliferative diabetic retinopathy leads to loss of vision for the following reasons:
Vitreous hemorrhage: Vitre is a gel-like substance that fills the inside of the eye. Sensitive new vessels can bleed into the vitreous. If the bleeding is small, the patient will see only a few dark and moving spots. A large bleeding can completely close the view. Depending on the amount of blood may take days, months. Vitrectomy may be necessary if blood is not drawn within a sufficient time. Vitreous bleeding alone is not the cause of permanent loss of vision. If the macula is not damaged, visual acuity may return to the old level after surgery.
Traction retinal detachment: When proliferative diabetic retinopathy occurs, the scar tissue accompanying neovascularization shrinks and removes the retina from its normal position. Wrinkles in the macula cause distorted vision. When a large portion of the macula or retina is dislodged, more severe vision loss may occur.
Neovascular glaucoma: Occasional intestinal obstruction in the retina leads to abnormal vessel formation on the iris (the colored part of the eye) and the outflow of the eye fluid is prevented. The eye pressure increases and an eye disease called neovascular glaucoma causes serious damage to the visual nerve. Argon laser photocoagulation in the early period will prevent neovascular glaucoma. In some cases, cryo treatment may be performed instead of laser.
How is diabetic retinopathy diagnosed?
The best way to detect changes in the eye is to have a good eye examination. Your ophthalmologist can detect and treat a serious retinopathy before you become aware of the visual problems. The ophthalmologist raises your baby with drops and evaluates the inside of your eyes with the necessary tools. If your doctor detects diabetic retinopathy, he or she may take color photographs to assess the need for treatment or take a special drug film called fluorescein angiography (FFA). In this test, a yellow drug is given from the arm. With a special device, the photos are taken while the drug is reviewed. With this test, the extent of the damage caused by diabetes to the eye is understood and helps with treatment.
How is diabetic retinopathy treated?
The best treatment is to prevent the development of retinopathy as long as possible. The risk of long-term vision loss is significantly reduced if blood glucose is constantly controlled.
Argon laser treatment: Laser therapy is recommended for people with macular edema, proliferative diabetic retinopathy and neovascular glaucoma. The main aim of treatment is to prevent more visual loss. The loss of vision loss due to macular edema is not unusual, but there may be an increase in the number of patients. After treatment, some patients can see laser spots in the visual field. These spots diminish over time, but may not fade. In proliferative diabetic retinopathy, the laser is applied to the entire retina outside the macula. It is called panretinal photocoagulation. This prevents abnormal vessels from shrinking and growing again. It also reduces the chance of vitreous bleeding and shrinkage in the retina.
Sometimes a large number of laser treatments may be required. Although the aim of laser treatment is to help keep the current vision, it does not completely improve diabetic retinopathy and may not always stop the vision loss process. For treatment with argon laser, the patient is seated in the normal examination chair. The patient does not need to be anesthetized or injected. Only a few eye drops can be applied. The treatment is done in several sessions and each session lasts 10-15 minutes. Largely patients are prevented from going bad. There is no serious side effect except narrowing of vision area or decreased vision.
Vitrectomy: Vitrectomy may be required in advanced proliferative diabetic retinopathy. This is a microsurgical procedure and is performed under operating room conditions. During surgery, blood is filled with vitreous and replaced with a clear solution. Before planning the vitrectomy, the ophthalmologist waits a few months to see if the blood can be removed by itself. Vitrectomy also prevents subsequent bleeding due to abnormal vessels. It can be repaired during the vitrectomy surgery if it is detached from the retina. In this case, surgery must be done early, because the distortion or tractional retinal detachment in the macula may cause permanent vision loss. The longer the macula remains wrinkled or dislocated, the greater the loss of vision.
Visual loss can be significantly impaired: If you have diabetes, you should know that today, only a small proportion of patients with retinopathy with advanced diagnosis and treatment methods experience severe vision problems. The best way to prevent vision loss is early detection of diabetic retinopathy. You can also check your blood sugar regularly and if you go through regular eye examinations, you will reduce your risk of vision loss considerably.
Which intervals should be examined?
Diabetic patients should be examined at least twice a year by expanding their eyes. When diabetic retinopathy is diagnosed, more frequent eye examinations may be required. As the retinopathy may progress rapidly during pregnancy, pregnant women with diabetes should undergo an eye examination within the first three months of pregnancy. If you are going to have eyeglasses, your blood sugar should be under control for at least five to ten days. When blood glucose levels are high, the glasses may not be suitable when blood sugar returns to normal. Even if there is no retinopathy, rapid changes in blood sugar can cause a change in the vision of both eyes.