Diabetic eye disease: early detection crucial in preserving sight. (Advertising Supplement).

Diabetes affects nearly 16 million Americans, damaging their kidneys, peripheral nerves and eyes. In the eyes, diabetes damages blood vessels in the retina, the tissues that line the back of the eye and allow one to see.

The retinal lesions of diabetes are known as diabetic retinopathy. This is the leading cause of blindness in working age Americans. It is estimated that more than 8,000 diabetics become blind every year from retinal complications. In the San Fernando Valley, there are about 82,000 diabetics. Of this number, 60 percent are diagnosed with diabetic retinopathy.

Much of this blindness can be prevented if the retinopathy is detected early enough and by the correct specialist for treatment with laser photocoagulation surgery or vitreous surgery. The optimal time for treatment is before a diabetic experiences visual symptoms, such as blurred vision, dark floaters or loss of vision.

Providing timely treatment depends on improving the diagnosis of the diabetic patient without symptoms through careful examination of the retina by a retina specialist.

There are two main types of diabetic retinopathy. The first is Nonproliferative Diabetic Retinopathy, in which the retinal capillaries, small blood vessels in the retina, are damaged and leak blood, fluid, and fat deposits into the retina in the center of vision, known as macular edema. To see this, a retina specialist has to dilate the patient's eyes and look to the back of the eye with special instruments.

Also, a test known as fluorescein angiography, photographs of the retina after fluorescein dye injected into the arm vein. It is used to make the diagnosis and plan for laser surgery. The treatment performed is focal laser photocoagulation surgery using anesthetic drops and a contact lens. It takes about 3 months for the full effect of the laser surgery to take effect. The second and more advanced type of diabetic retinopathy is the Proliferative type. In this type, the diabetes damages so many blood vessels in the eye that the retina does not receive sufficient blood flow. As a result, new blood vessels are formed in the retina and these can bleed into the vitreous jelly that fills the eye and detach the retina, both of which can cause dramatic decreases in vision.

To diagnose this condition, the retina specialist must dilate the patient's eyes and look with special instruments to see the back of the eye. Also, fluorescein angiography and an ultrasound test of the eye can help evaluate the extent of the disease.

Treatments include panretinal laser photocoagulation surgery or vitreous surgery where the blood is removed from the eye and the retina reattached depending on the severity of the condition.

National collaborative studies have shown conclusively that the risk of blindness can be reduced by well-timed laser photocoagulation surgery and vitreous surgery. In general, diabetics should have screening dilated retinal exams every year or more often if any diabetic retinopathy is detected. Early detection leads to early treatment and better vision in the long term.

Sanjay Logani, M.D., F.A.C.S. is a Retina Specialist with practices in Beverly Hills, Northridge, Burbank, and Encino-Tarzana Regional Medical Center in California.