What is Diabetic Retinopathy?
Within the structure of the eye, there is a very delicate tissue that lines the inside of the eye. This fragile lining is called the retina. The retina receives light and transmits images to the brain. Diabetes causes damage to small blood vessels throughout the body, including the retina. In diabetic retinopathy, damage from deteriorating blood vessels can cause visual problems.
What Are the Symptoms of Diabetic Retinopathy?
During a dilated eye examination, the doctor will be able to look into the back of the eye to monitor the condition of the blood vessels. With diabetes, leaking or bleeding vessels may be visible even before the patient notices any effect on their vision. Blurry vision may indicate a swelling in the retina. When bleeding occurs, vision may become very cloudy or be completely lost.
Are There More than One Type of Diabetic Retinopathy?
Yes, there are two types of diabetic retinopathy.
Background or Non-Proliferative Diabetic Retinopathy (NPDR)
This is caused by hemorrhages from the retinal blood vessels. Some of the smaller blood vessels narrow or even close, while others enlarge and form balloon-like sacs. When these vessels leak, they cause swelling and the formation of deposits called exudates. Any or all of these changes can cause decreased vision.
Proliferative Diabetic Retinopathy (PDR)
This starts out like NPDR. Closed blood vessels and the development of new abnormal blood vessels cause PDR. When these new, fragile vessels form, they grow on the retina’s surface or in the vitreous gel. The gel is a substance that fills the inside of the eyeball. If one of these new vessels leaks or breaks, the leakage enters into the vitreous gel. The new vessels are also associated with scar tissue that can pull on the retina causing wrinkling and detachment.
How Does the Physician Evaluate the Potential Problems?
During the dilated eye examination, the physician is able to see the vessels and will determine if additional testing should be ordered. Optical coherence tomography (OCT) is a non-invasive scanning LASER that produces a high definition map of the retina. It is used to evaluate the swelling associated with diabetic retinopathy. Another test, called fluorescein angiogram, is often times ordered so that careful monitoring of the eye can be obtained. This test involves injecting a water-soluble dye into a small vein on the hand or arm and taking a series of high-speed, specially filtered photographs as the dye travels through the blood vessels in the retina. These results help to evaluate the areas of leakage or new vessel formation. They also are valuable if it is determined that a laser procedure is needed.
If a Laser Can be Used, What Other Treatment Options are Available for this Condition?
- Today the mainstay of treatment involves laser surgery. This procedure utilizes a powerful beam of laser light energy on the retina. Selective destruction and sealing blood vessels of damaged areas of the retina can be achieved. Laser treatment is often helpful in maintaining the present vision and lowering the chance of future vision loss for as long as possible. This treatment involves no incisions and is often performed at the doctor’s office.
- Medication can also be used to treat diabetic retinopathy. The use of Anti-VEGF agents given inside the eye by your doctor have become an important treatment option for more advanced retinopathy cases. These medications work by blocking a substance known as vascular endothelial growth factor (VEGF), a substance that contributes to the growth of abnormal blood vessels and leakage. Steroid injections can also be used.
- Careful preparation of the eye prior to injection, including anesthetic and disinfecting drops, aid in preventing complications related to the injection. These medications can be given repeatedly depending on the response and may improve how well you see.
- A vitrectomy is a surgical procedure that is performed when bleeding has occurred in the vitreous gel, or if scar tissue is pulling on the retina. This type of surgery is usually performed after other methods of treatment have already been attempted.
- Yearly dilated eye exams are recommended to all with diabetes. More frequent monitoring may be required if retinopathy is present. The best treatment of diabetic retinopathy is strict control of your blood sugar. As well controlled blood sugar and A1C levels can significantly reduce the risk of long-term vision loss.