Retinopathy refers to diseases that affect the retina, the collection of light-sensitive cells lining the back half of each eye. The retina contains nerve cells that translate what you see into electrical impulses. These impulses are transmitted to the brain, where they are interpreted.

The retina contains many blood vessels. Abnormalities in these vessels cause several forms of retinopathy. Retinopathy can cause partial loss of vision or complete blindness. It can develop slowly or occur suddenly. Retinopathy can get better on its own at any time or it can cause permanent damage, depending on what's causing it and how far it has progressed.

Some types of retinopathy (for example, central serous retinopathy) do not have an obvious cause. Most forms of retinopathy, though, are caused by a known medical illness. Types of retinopathy caused by illnesses include:

• Retinopathy of prematurity occurs in some infants who are born prematurely or at a low birth weight. Retinal blood vessels develop at the back of the eye and grow outward to cover the area of the retina. When a child is born too early, this process doesn't have time to finish. An eye doctor (ophthalmologist) should closely monitor infants who are at risk by carefully examining the eyes. A baby is at risk if the baby is born before the end of the 29th week of pregnancy, or if the baby weighs less than 1,200 grams at birth. Babies who are born before the 35th week of pregnancy or who have a birth weight less than 1,500 grams also may need an eye examination if they have had other complications from their premature birth. Early stages of this illness involve only subtle changes without obvious symptoms. In more advanced stages, the retina can become detached, causing blindness.



• Diabetic retinopathy develops in people with diabetes. Two kinds of diabetic retinopathy have the potential to diminish vision: nonproliferative and proliferative retinopathy.
  
  In nonproliferative retinopathy, existing blood vessels in the retina deteriorate. Deteriorating blood vessels can become blocked or can develop balloonlike deformities called aneurysms. Fluids, fats and proteins leak out of the abnormal blood vessels. Fluid can collect in the area of the retina that is responsible for sharp vision (the macula). Macular swelling (edema) impairs the fine vision necessary for reading and detail work.
  
  In proliferative retinopathy, new, structurally unstable blood vessels grow on the surface of the retina. These unstable blood vessels cause frequent small hemorrhages (bleeding), causing local irritation with scar formation. In areas that have scarred, the clear mass of gel between the lens and the retina, called the vitreous, can adhere to the retina. These abnormal attachments between the retina and vitreous eventually distort the shape of the vitreous and cause the vitreous to pull against its tethers. This force can pull apart the layers of the retina, so that the retina can't function. This separation of layers is known as retinal detachment and is one of the most serious consequences of proliferative retinopathy. Sudden bleeding into the vitreous also can obscure vision, often quite suddenly.
  
  Diabetic retinopathy takes years to develop. It is present in close to 80% of people with type 1 diabetes who have had diabetes for 20 years or longer. Diabetic retinopathy is less predictable in people with type 2 diabetes. It can occur relatively soon after the diagnosis of type 2 diabetes is made because some people have no or minimal symptoms for many years before type 2 diabetes is diagnosed. Other people have very mild sugar abnormalities and may never develop retinopathy.
  
  People with diabetic retinopathy usually also have kidney damage caused by diabetes.
  
  Diabetic retinopathy is the leading cause of blindness in the United States for people between the ages of 20 and 64.



• Hypertensive retinopathy occurs in people who have high blood pressure (hypertension). It results from the thickening of the small arteries. Despite the potentially serious nature of high blood pressure, people with this disease frequently have no symptoms. Hypertensive retinopathy sometimes is discovered during a routine eye exam. High blood pressure causes blood vessel abnormalities, including blockages of retinal blood vessels and bleeding from them. These changes may not affect vision in early stages. Sudden, severe high blood pressure may cause swelling of the optic nerve (papilledema).



• Central serous retinopathy, begins for reasons that are not well understood. In this condition, fluid accumulates in the membrane behind your retina, called the choroid. This fluid seeps in between tissue layers in the retina and causes them to separate, resulting in blurred vision or poor night vision. This condition usually affects males between the ages of 20 and 50, but women also can get this condition. A person who develops this retinopathy is more likely than average to have been exposed to certain treatments or to have had certain medical problems, so these treatments and conditions are suspected to be possible triggers. Suspected triggers includ steroid medicines, pregnancy, antihistamines, antibiotics, alcohol abuse, nasal allergies, asthma, autoimmune problems and untreated high blood pressure. It is not clear whether emotional stress also may trigger this form of retinopathy, although some experts suspect a link.

Retinopathy of prematurity. There are no outward physical signs. Only an experienced ophthalmologist examining the eye through a dilated pupil can find signs of this illness.

Diabetic retinopathy. Symptoms may not be noticed until the late stages of the illness and can include:

• Blurred vision
• Sudden loss of vision in one or both eyes
• Black spots
• Flashing lights
• Difficulty reading or seeing detailed work

Hypertensive retinopathy. There are often no symptoms, though some people complain of blurred vision.

Central serous retinopathy. Symptoms include:

• Blurred or dim vision, sometimes coming on suddenly
• Blind spots
• Distorted shapes
• Reduced visual sharpness

Retinopathy of prematurity. An ophthalmologist examines the inside of the eye, including the retina and its blood vessels, as well as the optic disc, macula and retinal blood vessels for abnormalities.

Diabetic retinopathy. An ophthalmologist examines the retina and inside of the eye with an instrument called an ophthalmoscope. A dye may be injected into a vein in the arm. The dye then travels to the retina, where it can reveal leaky blood vessels.

Hypertensive retinopathy. A physician examines the eye with an ophthalmoscope and looks for tiny areas of the retina that look pale or white compared to the rest because these areas are not getting enough blood. The doctor also may see areas of bleeding from ruptured blood vessels. Occasionally, the retina may show areas of swelling, particularly at the area that controls fine vision (macula), or swelling of the optic nerve.

Central serous retinopathy. A doctor or ophthalmologist uses an ophthalmoscope to detect clear fluid that has seeped between one layer of the retina and another. Fluid between these layers can resemble bubbles on the retina, visible with an ophthalmoscope.

Retinopathy of prematurity. In most affected babies, this condition gets better on its own without treatment, and abnormal vessels disappear. More serious cases (about 6% of babies with this condition) will continue to get worse without treatment. Babies who need treatment are treated in the first few months of life. Within several months after treatment, it is usually possible to know whether there is any significant long-term damage to vision.

Diabetic retinopathy. Controlling blood sugar and blood pressure can slow or halt the progress of the disease, and treatments, usually with LASER, can repair existing damage.

Hypertensive retinopathy. Lowering blood pressure often can stop ongoing damage to the retina, although some damage that is established can persist.

Central serous retinopathy. Most cases go away without any treatment within three to four months. In cases that persist, laser is often used. Full vision can return within six months.

Retinopathy of prematurity. The first line of defense is regular prenatal care to prevent premature birth and complications during childbirth. Premature and low-birth-weight infants should be screened for retinopathy of prematurity if they are born at less than 36 weeks of gestation or weigh less than 4 pounds 6 ounces (2,000 grams) at birth. Because retinopathy of prematurity can be caused by or get worse from not having enough oxygen after birth or having too much, oxygen levels are monitored closely and adjusted accordingly.

Diabetic retinopathy. Controlling blood sugar and blood pressure are essential to prevent diabetic retinopathy. Doctors monitor blood sugar control by measuring a type of hemoglobin protein in the blood, hemoglobin A1C. If you are able to reduce your blood sugar average by the equivalent of one A1C point, you will reduce your risk of retinopathy by 35% over the next 10 years. Annual eye exams are crucial for people with diabetes. If proliferative and nonproliferative retinopathies are discovered during an annual exam, your doctor probably will recommend more frequent eye exams. Treatment can start before sight is affected and can delay vision impairment. The most commonly used treatment is laser.

Hypertensive retinopathy. Avoid high blood pressure by getting regular exercise, maintaining proper body weight, eating a healthy diet and seeing your doctor for regular checkups. Many Americans do not control their blood pressure well enough. It is important to take blood pressure medications as directed by your doctor if your blood pressure remains high even after you have made lifestyle changes.

Central serous retinopathy. Because the possible causes of this disease are still not understood, prevention is difficult. Many cases of central serous retinopathy have been associated with prescription corticosteroid treatment, so it's important to limit the amount of corticosteroids you take.

Retinopathy of prematurity. No treatment is recommended during the early stages, but close monitoring is essential. An ophthalmologist should examine high-risk infants before they are discharged from the newborn nursery and again at 8 weeks of age. If the disease is active, the infant should be examined every 1 to 2 weeks until he or she is 14 weeks old, and every 1 to 2 months after that. More advanced disease may require treatment to get rid of abnormal blood vessels. Treatment includes a procedure called cryotherapy, in which cold is used to destroy abnormal cells, and laser treatments. A detached retina can be reattached.

Diabetic retinopathy. To keep diabetic retinopathy from getting worse, blood sugar and blood pressure must be controlled to avoid complications. Specific treatment for diabetic retinopathy depends on the nature of the problem:

• Proliferative disease and macular edema (swelling or leaking of the main part of the retina) can be treated with laser therapy (photocoagulation).
• The formation of new blood vessels (neovascularization) is treated with laser surgery to create scars that slow the growth of new blood vessels. Laser surgery also is used to secure the retina to the back of the eye.
• Hemorrhaging that clouds vision can be treated by removing all or part of the vitreous material. Laser surgery may be used during the procedure.
• Retinal detachment requires surgery to reattach the retina to the back of the eye. All or part of the vitreous material may be removed at this time.

Hypertensive retinopathy. Medications can lower blood pressure and improve changes in the retina. People with very high blood pressure and swelling of the optic nerve require emergency treatment in a hospital.

Central serous retinopathy. This condition usually goes away on its own, but an ophthalmologist should monitor you closely for three to six months to make sure the condition improves. If it does not, laser treatment may be used to speed healing.

Call a doctor if you notice changes in your vision, particularly if they are sudden, including blurring, spots, flashes, blind spots, distortion, or difficulty reading or doing detail work.

Retinopathy of prematurity. In up to 85% of affected babies, this condition gets better on its own without treatment, and the abnormal vessels disappear. However, more advanced cases can lead to a number of eye problems, including blindness. Children with retinopathy of prematurity have an increased risk of retinal detachment, cataract, glaucoma, crossed eyes, lazy eye and nearsightedness.

Diabetic retinopathy. The outlook depends on how well blood pressure and blood sugar are controlled, how far the disease has progressed, and how closely it is monitored. Treatments can repair damage and slow the progress of the disease. Advanced stages of diabetic retinopathy lead to blindness.

Hypertensive retinopathy. Most changes in the retina caused by hypertensive retinopathy disappear after blood pressure has been lowered, although some signs of damage can remain.

Central serous retinopathy. Most cases go away on their own within three to four months. Full visual acuity usually returns within six months. Lasting symptoms can include distortion, decreased contrast sensitivity and difficulty with night vision. It's common for this condition to return.

American Academy of Ophthalmology
P.O. Box 7424
San Francisco, CA 94120-7424
Phone: 415-561-8500
Fax: 415-561-8533
http://www.aao.org

National Eye Institute
2020 Vision Place
Bethesda, MD 20892-3655
Phone: 301-496-5248
http://www.nei.nih.gov/

National Institute of Diabetes & Digestive & Kidney Disorders
Office of Communications and Public Liaison
Building 31, Room 9A06
31 Center Drive, MSC 2560
Bethesda, MD 20892-2560
Phone: 301-496-3583
http://www.niddk.nih.gov/

National Diabetes Information Clearinghouse
1 Information Way
Bethesda, MD 20892-3560
Toll-Free: 1-800-860-8747
TTY: 1-866-569-1162
Fax: 703-738-4929
http://diabetes.niddk.nih.gov/

American Academy of Pediatrics (AAP)
141 Northwest Point Blvd.
Elk Grove Village, IL 60007-1098
Phone: 847-434-4000
Fax: 847-434-8000
http://www.aap.org/

National Heart, Lung, and Blood Institute (NHLBI)
P.O. Box 30105
Bethesda, MD 20824-0105
Phone: 301-592-8573
TTY: 240-629-3255
Fax: 240-629-3246
http://www.nhlbi.nih.gov/