"Eye Microsurgery" Federal State Institution, Kaluga

DIABETIC RETINOPATHY

Diabetes mellitus is one of the most common endocrine diseases and every ten years the number of patients increases for 100%. Most commonly it can damage the eyes and cause blindness. According to information of the World Organisation of Health Protection blindness affects more than 15 million of diabetics every year. Unfortunately a diabetic is more likely to become blind than a person in the general population. But laser and operative surgery in complex are highly effective treatments for diabetic retinopathy.

What factors provide vision loss?

There are two groups of factors that provide vision loss:

The damage of the retina - the tissue in the eye that is sensitive to light (diabetic retinopathy, in some cases complicated by retinal detachment) and the optic nerve (diabetic neuropathy). Unfortunately, the treatment can save only undammaged cells and optic nerve fibers (prevent vision loss).

The damage of the structures that pass the light. In normal condition optic elements of the eye (the lens and the vitreous) that focus light rays onto the retina are transparent. Diabetics develop cataracts (lens opacity), bloodstroke into the vitreous or opacity in the vitreous with scar changes. Successful surgical treatment directed on recovering of the optic elements transparency can prevent vision loss.

Progression of diabetic retinopathy

Diabetic retinopathy is a potentially blinding complication of diabetes. Any persons with diabetes can develop retinopathy if they have had diabetes for long enough. Diabetes of all types predisposes to retinopathy. Retinopathy can be worsened by coexisting conditions of hypertension or high cholesterol, by overweight, affected kidneys or pregnancy.

Diabetes mellitus provokes the affection of all the blood vessels, but primary - of capillaries. Changes in the retina begin with damaged capillaries. In some cases the weakness in the blood vessel walls causes breaks and microscopic leaks (hemorrhages) are formed. But the symptoms of diabetic retinopathy could be not evident and if this process doesn't touch the small area in the center of the retina (the macula) most people don't notice any changes in their vision and don't consult their eye doctor.

After capillaries, veins are damaged. Gradually the number and the size of damaged vessels and exudates (retinal deposits occuring as a result of leaky vessels) increases. This causes vision loss. This stage of retinopathy is called nonproliferative (before new leaky vessels formation and scar tissue development).
Then blood vessels entirely close due to the damaged retinal ischemia (where the retina doesn't get enough oxygen) and new blood vessels and scar tissues begin to grow along the retina and in the vitreous they may exert traction and wrinkling of the retina and cause retinal detachment. This can result in vision loss.

Diabetic retinopathy is accompanied by abnormal changes of the vitreous (the clear substance which fills the eye). New blood vessels may bleed profusely and the disease progresses. But even the most intensive therapy don't lead to full blood resorption in the vitreous. The retina pulls away from the wall of the eyeball leading to vision loss. This is called proliferative retinopathy which require the surgery.

Nonproliferative retinopathy

Proliferative retinopathy

How diabetic retinopathy is treated?

Conservative medical treatment with different medications increase the strength of the blood vessel walls, provides resorption of hemorrhages and fatty deposits in the retina, improves the circulatory system of the eye. But, as practice shows, conservative treatment can't stop progressing of this disease and must be applied as auxiliary mesure.

The doctor may decide on laser photocoagulation to treat diabetic retinopathy. Early laser photocoagulation is rather effective, but it can only slow progression because diabetes mellitus is the main cause of diabetic retinopathy and the treatment usually doesn't restore lost vision. Patients with diabetes should be operated.

Vitrectomy

Vitrectomy ("vitreum" - the vitreous, "ectomy"- removal) is a surgical operation that involves removing of the fibrotic vitreous from the retina's surface to remove traction and wrinkling of the retina.

Vitrectomy is often done under local anesthesia, in some cases - under general. The doctor makes 3 tiny incisions in the eyeball and using small instruments removes the fibrotic vitreous, the vitreous is cleared from scar tissue where it is possible and from abnormal tissues. The final course of surgical treatment for every patient is determined in the course of the surgery.

In some difficult cases the process of scar formation can touch internal layers of the retina. That is why even when the scar tissue is dessected off the retina's surface, silicone oil is placed in the eye. It is necessary to help flatten the retina and prevent further retinal detachment. Sometimes silicone oil remains in the eye. When further scar formation is not observed during the postoperative period it can be removed from the eye.

Postoperative instructions

avoid sleeping on the side of the operated eye for 1-2 weeks;

don't rub your eyes;

bath or shower with extreme care, keeping soap and water away from eyes; you should use eye drops after shower;

use sunglasses;

avoid lifting objects;

avoid strenuous activity for 3 months;

keep head upright and bend at the knees;

don't use make-up for a month after the surgery;

avoid for at least 3 months physical exertion.