Retinopathy means abnormal processes happening in the retina. Hence as the name suggests, diabetic retinopathy refers to retinopathy due to diabetes. If you have diabetes, the body does not store and use sugar properly. High blood sugar levels can damage blood vessels in the retina. Retina is the layer situated at the back of the eye, which transmits images to the brain via the optic nerve.
Stages of Diabetic Retinopathy
Non Proliferative Diabetic Retinopathy (NPDR)
It is an early stage of diabetic retinopathy. In this stage blood vessels of the retina may leak fluid, protein or fats to form deposits called exudates or may rupture an cause hemorrhages or may get blocked. Many diabetics may have mild NPDR, which patient may not be aware o, as it does not affect vision. Hence retinal check up is necessary for all diabetics to detect early changes.
Proliferative Diabetic Retinopathy (PDR)
This is present when an abnormal new vessel (Neovascularization) begins growing on the surface of the retina. The main cause of PDR is wide spread closure of retinal blood flow. The retina responds by growing new blood vessels in an attempt to supply blood to areas where original vessels do not supply to retina. They are fragile and may cause bleeding in the retina. PDR can cause severe visual loss or blindness in the following ways:
- Vitreous Hemorrhage
- Tractional Retinal Detachment
- Neovascular Glaucoma
Macula is the most sensitive part of the retina. In diabetic maculopathy, fluid rich in fat and cholesterol leaks out of damaged vessel near the macula. It can cause damage to central vision.
Detection and prevention of vision loss
The problem with diabetic retinopathy is that there are “No Symptoms” in the early stages. When the retinopathy can be most easily treated, the patients will not notice visual changes. When the visual symptoms start, it is often too late. Hence consider the following steps to avoid vision loss.
Routine eye examination: Early detection and treatment can prevent visual impairment Retinopathy often has no symptoms. Quarterly eye check up may be required in severely affected cases.
Diabetes Control: Good sugar control helps to prevent or postpone the occurrence of retinopathy. However retinopathy may be present in spite of good control. Poorer the diabetes control, greater is the severity of retinopathy and increases the chances of hemorrhages in the eyes.
Control of blood pressure: Routine checkup of blood pressure is important. High BP accelerates the development and severity of retinopathy and increases the chances of hemorrhage in the eyes.
Diabetic retinopathy is a treatable condition by Laser. It is not cure for vision loss. It helps maintain vision and prevents blindness. The ocular tissue/retina where it is directed, absorbs the laser beam energy and is then changed to heat energy, which coagulates the tissue by burning, thus the laser is used to weld the leaking point in the retina and also to destroy the new blood vessels in the retina. By doing this we can prevent complications of retinopathy such as vitreous hemorrhage, fibrous scar tissue and retinal detachment. Laser photocoagulation is performed as an OPD procedure. Laser therapy causes little or no pain. Like any therapy, laser too can have side effects like blurring of vision or seeing some black spots in front of the eyes. The major reason for laser therapy is to salvage vision and to prevent complete blindness.
A surgery is done to remove the blood filled vitreous and replace it with clear solution. The abnormal vessels that cause bleeding are removed by this procedure
For diabetic maculopathy patients, Injection may be given in the eye to prevent swelling due to leakages and improve central vision
Remember: Loss of vision caused by this complication is preventable provided it is detected and treated on time. Hence periodic eye examinations are vital for all diabetics.