The retina is the nerve layer that lines the back of the eye. Its function is to sense light, capture all the images that we see, and send the information through the optic nerve to the brain. A retinal evaluation requires a thorough examination of the dilated eye and often requires getting images of the retina using multiple imaging types. The medical and surgical procedures performed by retina specialists are extremely delicate and range from in-office injections to highly technical surgeries conducted in the operating room. The ophthalmologists at our Huntington Beach optometry can assess what the state of your retina is in and if there are any procedures necessary at your consultation.
Learn about Common Retina Diseases
Diabetic retinopathy is damage to the back of the eye (retina) caused by complications of diabetes, which can eventually lead to blindness. Diabetic retinopathy can develop in anyone who has type 1 or type 2 diabetes. In longer cases of diabetes, your blood sugar is less controlled, increasing the likelihood of developing diabetic retinopathy.
As the condition progresses, diabetic retinopathy symptoms may include:
- Spots or dark strings floating in your vision (floaters)
- Blurred vision
- Fluctuating vision
- Dark or empty areas in your vision
- Vision loss
- Difficulty with perceiving color
Diabetic retinopathy may be classified as early or advanced, depending upon your signs and symptoms.
Early diabetic retinopathy
This type of diabetic retinopathy is called non-proliferative diabetic retinopathy (NPDR). This is because the new blood vessels aren’t growing, or proliferating. NPDR may be mild, moderate or severe. With NPDR, the walls of the blood vessels in the retina weaken. Tiny bulges (called microaneurysms) protrude from the vessel walls, sometimes oozing fluid and blood into the retina. As the condition worsens, the smaller vessels may close and the larger retinal vessels may begin to dilate and become irregular in diameter. Nerve fibers in the retina may begin to swell. Sometimes the central part of the retina (macula) begins to swell as well. This is called macular edema.
Advanced diabetic retinopathy
Proliferative diabetic retinopathy (PDR) is the most severe type of diabetic retinopathy. It’s called proliferative because new blood vessels begin to grow, or proliferate, in the retina. These new blood vessels are abnormal. They may grow into the clear, jelly-like substance that fills the center of your eye (vitreous). Eventually, scar tissue stimulated by the growth of new blood vessels may cause the retina to actually detach from the back of your eye. If the new blood vessels interfere with the normal flow of fluid out of the eye, pressure may build up in the eyeball, causing glaucoma. This can damage the optic nerve, sometimes resulted in blindness if not treated.
Complications can lead to serious vision problems including:
- Vitreous hemorrhage. The new blood vessels may bleed into the clear, jelly-like substance that fills the center of your eye, called vitreous. If the amount of bleeding is small, you might see only a few dark spots or floaters, but more severe cases will cause blood to fill the vitreous cavity and completely block your vision. Vitreous hemorrhage by itself won’t cause permanent vision loss, since the blood often clears from the eye within a few weeks or months. Unless your retina is damaged, your vision may return to its previous clarity.
- Retinal detachment. The abnormal blood vessels associated with diabetic retinopathy stimulate the growth of scar tissue, which can detach the retina from the back of the eye. This may cause spots floating in your vision, flashes of light or severe vision loss.
- Glaucoma. New blood vessels may grow in the front part of your eye and interfere with the normal flow of fluid out of the eye, causing pressure in the eye to build up. This pressure can damage the optic nerve.
- Blindness. Eventually, diabetic retinopathy, glaucoma or both can lead to complete vision loss.
Tests and Diagnosis
Diabetic retinopathy is diagnosed using a dilated eye exam. During this exam, your eye doctor will place drops in your eyes that make your pupils open widely, or dilate. This allows your doctor to get a better view inside your eye.
During the exam, your eye doctor will look for:
- Presence of a cataract
- Abnormal blood vessels
- Swelling, blood or fatty deposits in the retina
- Growth of new blood vessels and scar tissue
- Bleeding in the clear, jelly-like substance that fills the center of the eye (vitreous)
- Retinal detachment
- Abnormalities in your optic nerve
In addition, your eye doctor may:
- Test your vision
- Measure your eye pressure to test for glaucoma
As part of the eye exam, your doctor may do a retinal photography test called fluorescein angiography. First, your doctor will dilate your pupils and take pictures of the inside of your eyes. Next, your doctor will inject a special dye into your arm, and more pictures will be taken as the dye circulates through your eyes. Your doctor will use the dye in these images to pinpoint blood vessels that are closed, broken down or leaking fluid.
Optical coherence tomography
Your eye doctor may request an optical coherence tomography (OCT) exam. This imaging test provides cross-sectional images of the retina that show the thickness of the retina, helping to determine whether fluid has leaked into retinal tissue. Later, OCT exams can be used to monitor how treatment is working.
Treatment and Drugs
Treatment depends largely upon the type of diabetic retinopathy you have. Your treatment will also be affected by how severe the condition is, and how it has responded to previous treatments.
Early diabetic retinopathy
If you have non-proliferative diabetic retinopathy (NPDR), you may not need treatment right away. However, your eye doctor will closely monitor your eyes to determine if you need treatment at any particular point.
Beyond your eye doctor, it may also be helpful to work with your diabetes doctor (endocrinologist) to find out if there are any additional steps to improve your diabetes management. The good news is that when diabetic retinopathy is in the mild or moderate stage, good blood sugar control can usually slow it down.
Advanced diabetic retinopathy
If you have proliferative diabetic retinopathy, you’ll need surgical treatment right away. Sometimes surgery is also recommended for severe non-proliferative diabetic retinopathy. Depending on the specific problems with your retina, options may include:
Focal laser treatment. This laser treatment, also known as photocoagulation, can stop or slow the leakage of blood and fluid in the eye. It’s done in your doctor’s office or eye clinic. During this procedure, leaks from abnormal blood vessels are treated with laser burns, effectively fixing the leak. Focal laser treatment is usually done in a single session. Your vision will be blurry for about one day after the procedure. Occasionally you will be aware of small spots in your visual field that are related to the laser treatment. These generally disappear within several weeks.
If you had blurred vision from swelling of the central macula before surgery, you may not recover completely normal vision, but in some cases, vision does improve.
Scatter laser treatment. This laser treatment, also known as pan-retinal photocoagulation, can shrink the abnormal blood vessels. It’s done in your doctor’s office or eye clinic. During the procedure, the areas of the retina away from the macula are treated with scattered laser burns, causing the abnormal blood vessels to shrink and scar. Scatter laser treatment is usually done in two or more sessions. Your vision will be blurry for about one day after the procedure. Some loss of peripheral vision or night vision after the procedure is possible.
Vitrectomy. This procedure can be used to remove blood from the middle of the eye (vitreous). It may also remove any scar tissue that’s tugging on the retina. It’s done in a surgery center or hospital using local or general anesthesia. During the procedure, the doctor makes a tiny incision in your eye. Scar tissue and blood in the eye are removed with delicate instruments and replaced with a salt solution, helping maintain your eye’s normal shape.
Eye Injections. Injection of medication into the vitreous fluid in the eye can be effective in treating wet macular degeneration, diabetic retinopathy and broken blood vessels within the eye. In some cases, this treatment may help to partially recover vision.
Macular edema occurs when fluid and protein deposits collect on or under the macula of the eye (a yellow, central area of the retina) and causes it to thicken and swell. The swelling may distort a person’s central vision, since the macula is near the center of the retina at the back of the eyeball.
Macular edema is often a complication of diabetic retinopathy and is the most common form of vision loss for people with diabetes, particularly if it is left untreated.
Age-Related Macular Degeneration
Age-related macular degeneration (AMD) is a deterioration or breakdown of the eye’s macula. The macula is responsible for your central vision, allowing you to see fine details clearly.
AMD is a common eye condition among people who are 50 and older. It is among the leading causes of vision loss in older adults. As people age, the risk increases. Other risk factors include:
- Smoking. Research shows that smoking increases the risk of AMD twofold.
- Race. Caucasians are much more likely to get AMD than African Americans.
- Family History. People with a family history of AMD are at a higher risk.
In some people, AMD advances so slowly that vision loss does not occur for a long time, while in others, the disorder progresses faster and may lead to a loss of vision in one or both eyes. The vision loss makes it difficult to recognize faces, drive a car, read, write, or do other close work, such as sewing or fixing things around the house.
Despite the limited vision, AMD does not cause complete blindness. You will be able to see using your peripheral vision.
How is AMD detected?
The early and intermediate stages of AMD usually start without symptoms. During this time, only a comprehensive dilated eye exam can detect AMD. The eye exam may include the following:
Visual acuity test. This eye chart measures how well you see at distances.
Dilated eye exam.
Amsler grid. Your eye care professional also may ask you to look at an Amsler grid. Changes in your central vision may cause the lines in the grid to disappear or appear wavy, which is a sign of AMD.
Fluorescein angiogram. Your eye care professional may suggest you see an ophthalmologist to perform a fluorescein angiogram. With this test, your doctor injects a dye into your arm, and pictures are taken as the dye passes through the blood vessels in your eye. This test allows your doctor to identify leaking blood vessels and decide the best treatment.
Two forms of AMD that can cause vision loss: Dry and Wet
Dry AMD is the most common form of AMD in its early or intermediate stages. It occurs in about 90 percent of the people with this condition.
Dry AMD occurs when the light-sensitive cells in the macula slowly break down, gradually blurring the central vision in the affected eye. As dry AMD progresses, you may see a blurred spot in the center of your vision. Your eye care professional may call this “geographic atrophy.”
Over time, central vision in the affected eye can be slowly lost as less of the macula works.
Symptoms of Dry AMD
Dry AMD has few symptoms in the early stages. It is important to have your eyes examined regularly to prevent progression of the disease.
During later stages, blurred vision is the most common symptom of dry AMD. Objects also may not appear to be as bright as they used to be.
As a result, you may have trouble recognizing faces and may need more light for reading and doing other tasks. Both eyes can have dry AMD, or one eye may be affected before the other.
Vision loss and dry AMD
If you have vision loss from dry AMD in one eye only, you may not notice any changes in your overall vision. With the other eye functioning, you still can drive, read, and see fine details.
You may notice changes in your vision if dry AMD affects both eyes or if you develop the wet form of the disease. In any case, see an eye care professional for a comprehensive dilated eye exam if blurring occurs in your vision.
Can the dry form turn into the wet form?
All people who have the wet form had the intermediate stage of the dry form first. The dry form also can suddenly turn into the wet form, even during early stage AMD. Eye care professionals have no way to tell if the dry form will turn into the more severe wet form.
Dry AMD can turn into wet AMD at any time. You should get an Amsler grid from your eye care professional to check your vision for signs of wet AMD.
Diet might help
Studies have shown that people who eat a diet rich in green, leafy vegetables and fish have a lower risk of developing AMD.
While there is no definitive proof that changing your diet will reduce your risk of developing AMD or its progression, in the interest of maintaining good health in general, there is no reason not to eat a healthy diet, exercise, avoid smoking, and see your healthcare professional regularly.
A note about early stage dry AMD
Currently, no treatment exists for early stage dry AMD, which in many people shows no symptoms or loss of vision. Your eye care professional may recommend that you get a comprehensive dilated eye exam at least once a year to keep tabs on the condition.
If your condition worsens, your eye care professional may suggest that you take a specific high-dose supplement that contains antioxidants and zinc. Do not take these high-dose supplements unless your doctor expressly recommends them. Research shows that these high doses of specific vitamins and minerals may slow the condition’s progress.
What is wet AMD?
Wet AMD affects about 10 percent of all people with AMD. This type is more severe than early and intermediate stages of the dry form.
Wet AMD occurs when abnormal blood vessels behind the retina start to grow under the macula. These new blood vessels can be fragile, leaking blood and fluid. The blood and fluid cause the macula to swell and damage occurs rapidly. The damage may also cause scarring of the retina.
Although loss of central vision can happen quickly, eye care professionals can slow or stop the progression of wet AMD if it is detected before severe vision loss occurs.
What are the symptoms?
During the early stages of wet AMD, straight lines may appear wavy. People with wet AMD may also develop a blind spot, which results in the loss of central vision.
If you notice these or other changes to your vision, contact your eye care professional immediately. Again, eye care professionals may be able to treat the condition before severe vision loss occurs.
Treatment options for wet AMD
With early diagnosis and proper treatment, you can delay the progression of AMD. The earlier it is detected, the better your chances of keeping your vision. Wet AMD typically results in severe vision loss, but eye care professionals can try different therapies to stop further vision loss. You should remember that the therapies described below are not a cure. The condition may progress even with treatment.
Injections. One option to slow the progression of wet AMD is to inject drugs into your eye. With wet AMD, abnormally high levels of vascular endothelial growth factor (VEGF) are secreted in your eyes. This substance causes the growth of new abnormal blood vessels, and the anti-VEGF injection therapy blocks its effects. If you get this treatment, you may need multiple injections. Your eye care professional will likely deliver them monthly. Before each injection, your eye care professional will numb your eye and clean it with antiseptics. To prevent the risk of infection, a doctor may prescribe antibiotic drops.
Photodynamic therapy. This technique involves laser treatment of select areas of the retina. First, a drug called verteporfin will be injected into a vein in your arm. The drug travels through the blood vessels in your body, including any new, abnormal blood vessels in your eye. Your eye care professional then shines a laser beam into your eye to activate the drug in the blood vessels. Once activated, the drug destroys the new blood vessels and slows the rate of vision loss. This procedure takes about 20 minutes.
Laser surgery. Eye care professionals sometimes treat certain cases of wet AMD with laser surgery, though this is less common than other treatments. This treatment is performed in a doctor’s office or eye clinic. It involves using an intense beam of light against the new blood vessels in your eyes to destroy them. However, laser treatment also may destroy some surrounding healthy tissue and cause more blurred vision. Consult with your eye doctor before undergoing this procedure.
What is advanced AMD?
Both the wet form and the advanced dry form are considered advanced AMD. These conditions can occur in the same eye or a single eye. In most cases, only advanced AMD can cause vision loss.
People who have advanced AMD in one eye are at especially high risk of developing advanced AMD in the other eye, which may result in total vision loss.
However, research has shown that high doses of vitamins and mineral supplements may slow the progression of intermediate AMD to the more advanced stage.
A note about the AREDS formulation
Researchers stress that the AREDS formulation is not a cure. It will not restore vision already lost from the condition. Its function is to delay the onset of advanced AMD. It also may help people who are at a high risk of developing advanced AMD to keep their remaining vision.
Loss of Vision
Dealing with AMD and vision loss can be a traumatic experience. This is especially true of those who have just begun to lose their vision or have low vision. Having low vision means that even with regular glasses, contact lenses, medicine, or surgery, there is a difficulty in executing everyday tasks. Reading the mail, shopping, cooking, seeing the TV, and writing can all seem challenging.
However, help is available. You may not be able to restore your vision, but low vision services can help you make the most of what is remaining. You can continue enjoying friends, family, hobbies, and other interests just as you always have. The key is in utilizing these services as soon as possible.
Atlantis Eyecare has a trained low vision optometrist (Mary Ma, O.D.) who provides a low vision exam for those interested in using daily devices that can work best for you.