Retina Insight
Super-speciality Eye Hospital

Diabetes is a disease not limited to a single organ.

It’s a systemic disease which affects various organs in the body like eye, kidney, brain, heart. In eye diabetes causes damage to the back portion of the eye called the retina which is called Diabetic retinopathy. It can lead to swelling or bleeding in the retina and adjacent structures resulting in decreased vision.

It is divided into 5 stages; stage 1 is mild where systemic sugar control should suffice to stage 5 (advanced stage) where surgical procedure may be required.

Patient starts experiencing symptoms generally around stage 3 when swelling of the retina (macular edema) starts.

Macular degeneration could be due to various causes the most common among which is Age related macular degeneration (ARMD).

Diabetic retinopathy is different from ARMD as ARMD is generally limited to loss of central vision alone while diabetic retinopathy in advanced stages may lead to decrease in central as well as peripheral vision.

The prevalence of diabetic retinopathy in India is about 20% which means 1 in 5 patients of Diabetes has diabetic retinopathy.

The duration of disease is the most important risk factor which means that the longer the duration of disease in your body the more likelihood of having diabetic retinopathy.

Diabetes leads to hyperglycemia (raised sugars) which causes damage to the small blood vessels in the body including retina. Therefore, patients with uncontrolled sugars there is increased damage to these small blood vessels leading to damage of retinal cells

There is no fixed timeline for the occurrence of diabetic retinopathy but around 5% of patients have diabetic retinopathy at the time of diagnosis of diabetic retinopathy. Diabetic retinopathy will occur earlier in patients with uncontrolled sugars compared to patients with controlled sugars.

There is increasing evidence that diabetic retinopathy has genetic component as well. While all patient with diabetes are at risk of developing diabetic retinopathy, genetic factors can play an important role in further increasing the risk in predisposed individuals.

Diabetic retinopathy affects the retina (back part of the eye) and unfortunately cannot be detected without a complete eye examination.

An eye of a patient with diabetic retinopathy shows no changes on the outside compared to normal eye. The symptoms also may start much later after the onset of diabetic retinopathy. Therefore, it is important for a regular screening for diabetic retinopathy.

Screening for diabetic retinopathy means a detailed evaluation of the retina (back part of the eye) after dilating the eye with dilating drops.

No additional tests are required to screen a patient for diabetic retinopathy and the examination itself takes about 5 minutes.

Every diabetic patient should get his screening done once a year to look for retinopathy changes even before symptoms arise.

Diabetic retinopathy is generally not painful. In some cases with very advanced disease it can become painful if the new vessels develop on the Iris causing neovascular glaucoma.

Diabetic retinopathy can affect vision in mainly 2 ways.

It can lead to swelling of the retina causing difficulty in reading, using mobile or can lead to bleeding inside the eye which will cause sudden decrease in vision. Some patients may experience black clouds floating in front of the eye due to bleeding. Swelling of retina (Diabetic macular edema) is the most common cause of decreased vision in diabetic patients

Diabetic retinopathy can be diagnosed with retina evaluation by a trained retinal surgeon. A diagnosis of diabetic retinopathy can be made by clinical evaluation alone in majority patients. There are many adjuvant tests like OCT, fundus photography, FFA etc which play a role in certain cases and are used as and when required. OCT is used to assess the presence and severity of macular edema. FFA is used to evaluate diabetic retinopathy changes not visible on clinical evaluation.

Diabetes is treatable in a way that medicines can help keep blood sugar under control but as of now there is no cure for diabetes. Similarly, diabetic retinopathy treatment is aimed at keeping the condition under control, complete cure is not possible. We can treat the vision threatening complications of diabetic retinopathy with systemic care along with targeted eye care.

Diabetic retinopathy screening and treatment is done by ophthalmologist who specializes in Retinal diseases. However, systemic control of diabetes in consultation with a physician also plays an important role in management of diabetic retinopathy.

The symptoms due to diabetic retinopathy like vision loss can be reversible to certain extent provided we catch the disease at an early stage and undergo adequate and timely treatment. In advanced stages of diabetic retinopathy vision recovery is difficult and not always possible. Diabetic retinopathy is not completely reversible or will not go away completely but the progression of disease can be slowed with adequate control of systemic disease and regular eye checkup.

There is no scientifically proven treatment that can prevent diabetic retinopathy. Studies have shown that tight sugar control since the onset of diabetes is the most effective method of preventing or delaying the onset of diabetic retinopathy. Systemic control of sugars is the most important factor in relation to onset of diabetic retinopathy, severity of diabetic retinopathy and also treatment response.

Diabetic retinopathy treatment is divided into two parts – systemic treatment to control sugars by physician and ocular treatment for ocular complications. It is important to understand that ocular treatment will be effective only if blood sugar is under control. The treatment will be less effective if patient continues to have uncontrolled diabetes. Therefore, systemic control and ocular treatment both have equal role to play in treatment of diabetic retinopathy.

Ocular treatment of diabetic retinopathy involves 3 steps:

Step 1: Intravitreal injections. These injections help to control the swelling in the retina (macular edema) as well as take care of early stage new vessels (flat neovascularization) that can form in diabetic retinopathy

Step 2: Laser. If the disease has progressed beyond the scope of intravitreal injections (Fibrovascular proliferation) then the patient may need laser (light) treatment in addition to intravitreal injections

Step 3: Surgery. If the diabetic retinopathy is in advanced stage (Tractional retinal detachment, Vitreous hemorrhage) then surgical procedure is the only option. The aim of regular screening and follow up is to prevent the disease to progress to a stage where surgical procedure is required