WHAT SHOULD YOU KNOW ABOUT - DIABETIC RETINOPATHY?

What is Diabetic retinopathy?
Everyone knows that diabetes is one of the most important causes of chronic renal failure, stroke and heart attack, but very few are aware that diabetic retinopathy is also a common condition amongst diabetics and is a sight threatening condition. It is the affection of retina resulting from diabetes of long duration which is uncontrolled. The microangiopathy triggered by the presence of diabetes is the starting point of the various retinal changes. Various changes which can be take place in the retina are: microaneury formation, dot and blot haemorrhage, flame shaped haemorrhage, large retinal haemorrhage, presence of soft and hard exudate, venous changes, retinal oedema, macular oedema, neovascularization and retinal detachment. The list is large but the important fact is that it is slow process and it does not occur overnight. If ophthalmologist to look for the Diabetic Retinopathy a proper treatment examines the diabetic patients regularly can be instituted at the right time. 1 indicates normal retina and 2 shows Diabetic Retinopathy changes.

THE FUNDUS WITH DIABETIC RETINOPATHY CHANGES?
Why regular check-up of eye?
Diabetic Retinopathy, for a very long time, is symptomless and patients themselves are unable to appreciate the changes in the retina. Visual acuity affection is a very late feature and in majority is associated with very advanced stages of Diabetic Retinopathy. Eye is the only organ in the body where the diabetic changes can be visualized by naked eye during the routine examination it can be picked up much earlier, so that treatment can be instituted at the earliest.

WHAT ARE THE REASONS FOR VISUAL LOSS DUE TO DIABETIC RETINOATHY?

The causes of visual disturbance in earlier changes is various forms of maculopathies, which include focal leak, diffuse oedema, ischaemia of macular area and deposits of exudates in the central area. Vitreous haemorrahge and tractional retinal detachment cause visual loss, usually in advanced stages of the disease. There is no correlation between severity of Diabetic Retinopathy and extent of visual disturbance.

Management of Diabetic Retinopathy:
Basically from the treatment of view the Diabetic Retinopathy can be classified as:
1. Back ground Diabetic Retinopathy.
2. Preproliferative Diabetic Retinopathy.
3. Proliferative Diabetic Retinopathy
Any of these stages can be associated with " Maculopathy".

Medical Treatment- Strict diabetes control is mandatory for any Diabetic Retinopathy case. No medicine has been found effective against the Diabetic Retinopathy. Therefore, I do not give any medicine for Diabetic Retinopathy.

Laser treatment- Laser photocoagulation is the only treatment, which is available at present and is effective in the management of Diabetic Retinopathy. It does not arrest or reverse the Diabetic Retinopathy changes but certainly it prevents/ delays the sight threatening complications due to the Diabetic Retinopathy. Hence, all patients with Diabetic Retinopathy are not treated with laser, but the disease decides it. Fundus Flourescein Angiography (FFA) is very useful in deciding laser treatment. Proliferative Diabetic Retinopathy must be treated with laser. Preproliferative must be treated with laser if the progression of Diabetic Retinopathy has been found to be rapid in a particular patient. Majority of Maculopathy patients need to be treated with laser. Leaking areas/ microaneurysms can be treated in background Diabetic Retinopathy stage. One must remember that we do not expect improvement in vision after laser treatment. However, in some patients with Maculopathy,we can expect improvement in vision after laser treatment in couple of months time. The main purpose of laser treatment is to maintain the existing vision for a longer period of time.

Which type of laser?
There are many types of lasers available for this purpose: Argon Laser, Diode laser, frequency doubled Nd-YAG laser, etc. All these lasers have similar effect on the retina and produce the same result but the Argon laser is the gold standard amongst all the fundus sows appearance after the laser treatment.

What is Fundus Fluorescein Angiography (FFA)?
This is done by injecting intra venous and "sodium fluorescein dye" which binds with protein and circulates all over the body and reaches the retinal circulation in 10 - 12 seconds. Retinal pictures are than taken by fundus camera using the appropriate filters. The test gives information about the Diabetic Retinopathy changes in minute details.
Thus, this is a very useful test for diabetic. This is very common test and consider as very safe however, Nausea, vomiting mild to the dye is Common feature. Very rarely it can result in severe reaction to the dye. I personally always do this test before laser treatment since a permanent record of his retinal status can be maintain a part from knowing the sage of the Diabetic Retinopathy. For other patients, I decide FFA test upon a stage of Diabetic Retinopathy deducted on routine examination. All diabetics need not be subjected to FFA test.
FFA in Diabetic Retinopathy changes in surgical treatment.
This is indicated mainly in the neglected advanced cases of Diabetic Retinopathy which has cause vitreous haemorrhage, retinal detachment and vitreous bands or opacities. In general, the prognosis is poor in patients requiring surgical treatment. Most of the patients would not reach this stage if he has been manage by ophthalmologists from the initial periods of his diabetes detection.

Some important points to remember:
1. Diabetes affects retina in the form of Diabetic Retinopathy and it is sight threatening.
2. Visual acuity has no correlation with the stage/severity of Diabetic Retinopathy.
3. Diabetic Retinopathy is more common in the uncontrolled, long standing diabetics.
4. Retina must be examined by ophthalmologist in mumbai on the first diagnosis of diabetes and frequently on the advice of ophthalmologist at Doctor Eye Institute, Mumbai thereafter. It is a possibility that diabetics diagnosed today may be having undiagnosed diabetes for a long period of time.
5. On many occasions, diabetes has been diagnosed by the presence of diabetic retinopathy detected by ophthalmologist at Doctor Eye Institute, Mumbai.
6. Laser treatment is the only useful/effective treatment available today for Diabetic Retinopathy.
7. Laser photocoagulation will not improve eyesight in majority of patients but it definitely slows down the rate of deterioration.
8. FFA is useful investigation for Diabetic Retinopathy and this test is fairly safe.
9. If managed properly diabetics can have proper vision for a long time.
10. Management of Diabetic Retinopathy is not an one time affair but they need to be followed up regularly, even after laser photocoagulation.
11. Diabetic Retinopathy is one of the major cause of blindness in developed countries.
12. Blindness due to Diabetic Retinopathy is irreversible in majority of patients, so early detection and regular management is very important.