Macular degeneration is an eye disorder that slowly destroys sharp, central vision. This makes it difficult to see fine details and read.
The disease is most common in people over age 60, which is why it is often called age-related macular degeneration (ARMD, or AMD).
Macular degeneration is a disease of the retina that affects the macula in the back of the eye. The macula is important for clear central vision, allowing an individual to see fine details. There are two types of macular degeneration, dry and wet. Dry macular degeneration is more common and is characterized by the thinning of the retina and drusen, small yellowish-white deposits that form within the retina. The dry form of macular degeneration is usually mild. Wet macular degeneration can happen more quickly and be more serious. It occurs when vessels under the retinal layer hemorrhage and cause the retinal cells to die creating blind spots or distorted vision in the central vision. The disease becomes increasingly common amongst people in each succeeding decade over 50.
The retina is at the back of the eye. It changes light and images that enter the eye into nerve signals that are sent to the brain. A part of the retina called the macula makes vision sharper and more detailed.
AMD is caused by damage to the blood vessels that supply the macula. This change also harms the macula.
There are two types of AMD:
Dry AMD occurs when the blood vessels under the macula become thin and brittle. Small yellow deposits, called drusen, form. Almost all people with macular degeneration start with the dry form.
Wet AMD occurs in about 10% of people with macular degeneration. New abnormal and very fragile blood vessels grow under the macula. These vessels leak blood and fluid. This type of AMD causes most of the vision loss associated with the condition.
Doctors are not sure what causes AMD. The condition is rare before age 55. It occurs most in persons 75 years or older.
You may not have any symptoms at first. As the disease gets worse, you may have problems with your central vision.
SYMPTOMS OF DRY AMD
The most common symptom of dry AMD is blurred vision. Objects in the center part of your vision often look distorted and dim, and colors look faded. You may have trouble reading print or seeing other details. But you can see well enough to walk and do most daily activities.
As dry AMD gets worse, you may need more light to read or do everyday tasks. A blurred spot in the center of vision gradually gets larger and darker.
In the later stages of dry AMD, you may not be able to recognize faces until they are close.
SYMPTOMS OF WET AMD
The most common early symptom of wet AMD is that straight lines look distorted and wavy.
There may be a small dark spot in the center of your vision that gets larger over time.
With both types of AMD, central vision loss can occur quickly. If this happens, you will need to be seen right away by an ophthalmologist. Make sure this eye doctor has experience in treating problems with the retina.
You will have an eye exam. Drops will be placed into your eyes to widen (dilate) your pupils. The eye doctor will use special lenses to view your retina, blood vessels, and optic nerve.
The eye doctor will look for specific changes in the macula and blood vessels and for drusen.
You may be asked to cover one eye and look at a pattern of lines called an Amsler grid. If the straight lines look wavy, it may be a sign of AMD.
Other tests that may be done include:
Using special dye and camera to look at blood flow in the retina (fluorescein angiogram)
Taking a photo of the inner lining of the eye (fundus photography)
Using light waves to view the retina (optical coherence tomography)
If you have advanced or severe dry AMD, no treatment can restore your vision.
If you have early AMD and do not smoke, a combination of certain vitamins, antioxidants, and zinc may prevent the disease from getting worse. But it cannot give you back vision that is already lost.
The combination is often called the "AREDS" formula. The supplements contain:
500 milligrams of vitamin C
400 international units of beta-carotene
80 milligrams of zinc
2 milligrams of copper
Only take this vitamin combination if your doctor recommends it. Make sure your doctor knows about any other vitamins or supplements you are taking. Smokers should not use this supplement.
AREDS may also benefit you if you have a family history and risk factors for AMD.
The supplements lutein and zeaxanthin may also be helpful, although they are not part of the AREDS formula.
If you have wet AMD, your doctor may recommend:
Laser surgery (laser photocoagulation) -- a small beam of light destroys the leaking, abnormal blood vessels.
Photodynamic therapy -- a light activates a drug that is injected into your body to destroy leaking blood vessels.
Special medicines that prevent new blood vessels from forming in the eye are injected into the eye (this is a painless process).
Low-vision aids (such as special lenses) and therapy can help you use the vision that you have more effectively, and improve your quality of life.
Close follow-up with your eye doctor is important.
For dry AMD, visit your eye doctor once a year for a complete eye exam.
For wet AMD, you likely need frequent, perhaps monthly, follow-up visits.
Early detection of vision changes is important because the sooner you are treated, the better your outcome. Early detection leads to earlier treatment and often, a better outcome.
The best way to detect changes is by self-testing at home with the Amsler grid. Your eye doctor can give you a copy of the grid. Or you can print one from the Internet. Test each eye individually while wearing your reading glasses. If the lines look wavy, call your eye doctor right away for an appointment.
AMD does not affect side (peripheral) vision. This means complete vision loss never occurs. AMD results in the loss of central vision only.
Mild, dry AMD usually does not cause disabling central vision loss.
Wet AMD often leads to significant vision loss.
In general, with AMD you may lose the ability to read, drive a car, and recognize faces at a distance. But most people with AMD can carry out daily tasks without much difficulty.
If you have AMD, your health care provider may recommend that you check your vision every day with an Amsler grid. Call your provider immediately if the lines look wavy. Also call if you notice other changes in your vision.
Fuchs' (pronounced Fooks) dystrophy is an eye disease in which cells lining the inner surface of the cornea slowly start to die off. The disease usually affects both eyes.
Fuchs' dystrophy can be inherited, which means it can be passed down from parents to children. If either of your parents has the disease, you have a 50% chance of developing the condition.
However, the condition may also occur in persons without a known family history of the disease.
Fuchs' dystrophy is more common in women than in men. Vision problems usually do not appear before age 50, although doctors may be able to see signs of the disease in affected persons at an earlier age, usually in their 30s and 40s.
Fuchs' dystrophy affects the thin layer of cells that line the back part of the cornea. These cells help pump excess fluid out of the cornea. As more and more cells are lost, fluid begins to build up in the cornea, causing swelling and a cloudy cornea.
At first, fluid may build up only during sleep, when the eye is closed. As the disease gets worse, small blisters may form. The blisters get bigger and may eventually break, causing eye pain. Fuchs' dystrophy can also cause the shape of the cornea to change, causing further vision problems.
Deep lamellar keratoplasty (DLK) is an alternative to a traditional transplant. In this procedure, only the deep layers of the cornea are replaced with donor tissue. The procedure requires no stitches. Recovery time is faster and there are fewer complications, such as rejection.
Fuchs' dystrophy gets worse over time. Without a corneal transplant, a patient with severe Fuchs' dystrophy may become blind or have severe pain and very reduced vision.
Mild cases of Fuchs' dystrophy often worsen after cataract surgery. A cataract surgeon will evaluate this risk and may modify the technique or the timing of your cataract surgery.
There is no known prevention. Avoiding cataract surgery or taking special precautions during cataract surgery may help slow down the course of the disease.
Dry eye usually occurs in people who are otherwise healthy. It becomes more common with age. This can occur due to hormonal changes that make your eyes produce fewer tears.
Other common causes of dry eyes include:
Dry environment or workplace (wind, air conditioning)
The first step in treatment is artificial tears. These come as preserved (screw cap bottle) and unpreserved (twist open vial). Preserved tears are more bottle) convenient, but some people are sensitive to preservatives. There are many brands available without a prescription.
Start using the drops at least 2-4 times per day. If your symptoms are not better after a couple of weeks of regular use:
Increase use (up to every 2 hours)
Try a different brand
Talk to your health care provider if you can’t find a brand that works for you
Other medical treatments may include:
Fish oil 2-3 times per day
Glasses, goggles or contact lenses that keep moisture in the eyes
Medicines such as Restasis, topical corticosteroids, and oral tetracycline and doxycycline
Tiny plugs placed in the tear drainage ducts to moisture stay on the surface of the eye longer
Don't smoke and avoid second-hand smoke, direct wind, and air conditioning.
Use a humidifier, especially in the winter.
Limit allergy and cold medicines that may dry you out and worsen your symptoms.
Purposefully blink more often. Rest your eyes once in a while.
Clean eyelashes regularly and apply and warm compresses.
Some dry eye symptoms are due to sleeping with the eyes slightly open. Lubricating ointments work best for this problem. You should use them only in small amounts since they can blur your vision. It is best to use them before sleep.
Surgery may be helpful if symptoms are because the eyelids are in an abnormal position.
The conjunctiva is exposed to bacteria and other irritants. Tears help protect the conjunctiva by washing away bacteria. Tears also contain proteins and antibodies that kill bacteria.
There are many causes of conjunctivitis. Viruses are the most common cause. Viral conjuctivitis is referred to as "pink eye." Pink eye can spread easily among children.
Use of contact lenses (especially extended-wear lenses)
Newborns can be infected by bacteria in the birth canal. This condition is called ophthalmia neonatorum, and it must be treated immediately to preserve eyesight.
Allergic conjunctivitis may respond to allergy treatment. It may disappear on its own when you avoid your allergy triggers. Cool compresses may help soothe allergic conjunctivitis.
Antibiotic medication, usually eye drops, is effective for bacterial conjunctivitis. Viral conjunctivitis will disappear on its own. Many doctors give a mild antibiotic eyedrops for pink eye to prevent bacterial conjunctivitis.
You can soothe the discomfort of viral or bacterial conjunctivitis by applying warm compresses (clean cloths soaked in warm water) to your closed eyes.
In babies, it rarely causes problems because the lashes are very soft and do not easily damage the eye. In older people, the condition is usually caused by a spasm or weakening of the muscles surrounding the lower part of the eye.
Although rare, trachoma infection can cause scarring of the inner side of the lid, which may cause entropion. Trachoma scarring is one of the three leading causes of blindness in the world.
