How Diabetes Causes Blindness - Topic Overview
The later stages of retinal injury are called proliferative retinopathy, because new fragile blood vessels grow to supply the damaged areas of the retina. These new blood vessels can bleed into the vitreous gel, the gel-filled area in front of the retina. Over time, scar tissue that forms from bleeding can cause the retina to detach from the wall of the eye (retinal detachment) and cause loss of vision.
Severe proliferative retinopathy may be treated with laser surgery in order to save vision. Your eye doctor may use more aggressive laser therapy, called scatter (pan-retinal) photocoagulation. This process is more thorough than that used in localized photocoagulation. And it may require more individual treatments. But it allows your doctor to minimize the growth of new blood vessels across the back of your retina. Severe proliferative retinopathy may also be treated with medicines that slow the growth of abnormal blood vessels in the retina. The growth of these vessels is triggered by a protein called vascular endothelial growth factor (VEGF). Anti-VEGF medicines, such as ranibizumab (Lucentis), block the effects of VEGF.
Laser treatments may not always work in treating proliferative retinopathy. If you have retinal detachment or hemorrhages that cannot be repaired, your retinal specialist will need to use a surgical technique to try to restore your vision. This surgical technique, called pars plana vitrectomy, attempts to repair your retina and reduce hemorrhaging. Like many surgical techniques, it has several risks and is much more likely to damage your eye than laser surgery.
Other eye problems
People who have diabetes are also at risk for other problems, such as cataracts and glaucoma, that damage vision. They are also at risk for a severe form of glaucoma called neovascular glaucoma. Cataracts are frequently caused by a lifetime of sun exposure, and diabetes speeds up their formation.
The following table outlines the major causes of blindness in people who have diabetes.
Causes of blindness and how to prevent it
How it causes vision loss
|Diabetic retinopathy||Damages the retina, the section of your eye responsible for capturing visual information|
- Controlling your blood sugar
- Controlling blood pressure
- Having regular eye exams
- Using laser surgery early to treat retinopathy
|Glaucoma||Increases pressure in the eye, which results in damage to your retina|
- Having regular eye exams to check for the disease
|Cataracts||Cloud the lens, the section of your eye responsible for focusing light on your retina|
- Protecting your eyes from ionizing radiation (X-rays) and UV radiation (sunlight)
- Controlling blood sugar levels