Ocular Disorders

Macular degeneration is the leading cause of severe vision loss in people over age 60. It occurs when the small central portion of the retina, known as the macula, deteriorates. The retina is the light-sensing nerve tissue at the back of the eye. Because the disease develops as a person ages, it is often referred to as age-related macular degeneration (AMD). Although macular degeneration is almost never a totally blinding condition, it can be a source of significant visual disability.

There are two main types of age-related macular degeneration:

• Dry form. The “dry” form of macular degeneration is characterized by the presence of yellow deposits, called drusen, in the macula. A few small drusen may not cause changes in vision; however, as they grow in size and increase in number, they may lead to a dimming or distortion of vision that people find most noticeable when they read. In more advanced stages of dry macular degeneration, there is also a thinning of the light-sensitive layer of cells in the macula leading to atrophy, or tissue death. In the atrophic form of dry macular degeneration, patients may have blind spots in the center of their vision. In the advanced stages, patients lose central vision.
• Wet form. The “wet” form of macular degeneration is characterized by the growth of abnormal blood vessels from the choroid underneath the macula. This is called choroidal neovascularization. These blood vessels leak blood and fluid into the retina, causing distortion of vision that makes straight lines look wavy, as well as blind spots and loss of central vision. These abnormal blood vessels and their bleeding eventually form a scar, leading to permanent loss of central vision.

Most patients with macular degeneration have the dry form of the disease and can lose some form of central vision. However, the dry form of macular degeneration can lead to the wet form. Although only about 10% of people with macular degeneration develop the wet form, they make up the majority of those who experience serious vision loss from the disease.

A cataract is a painless, cloudy area in the lens of the eye that blocks the passage of light to the retina. The retina is the nerve layer at the back of the eye. The nerve cells in the retina detect light entering the eye and send nerve signals to the brain about what the eye sees. Because cataracts block this light, they can cause vision problems.

Aging and exposure to sunlight can cause cataracts. Changes in your eyes are often a normal part of aging. But the changes do not always lead to cataracts.

Cataracts can also happen after an eye injury, as a result of eye disease, after you use certain medicines, or as a result of health problems such as diabetes.

Sometimes children are born with cataracts.

Cataracts can affect your vision.

• You may have cloudy, fuzzy, or foggy vision.
• You may see glare from lamps or the sun. You may have trouble driving at night because of glare from car headlights.
• You may need frequent changes to your eyeglasses prescription.
• You may get double vision in one eye.
• Your near vision may improve for a short time if you get a cataract. This temporary improvement is called second sight.

Surgery can remove cataracts. For most adults, surgery is only needed when vision loss caused by a cataract affects their quality of life.

Glaucoma is the name for a group of eye diseases that damage the optic nerve. This nerve carries information from the eye to the brain. When the nerve is damaged, you can lose your vision.

Glaucoma is one of the most common causes of legal blindness in the world. At first, people with glaucoma lose side (peripheral) vision. But if the disease isn’t treated, vision loss may get worse. This can lead to total blindness over time.

There are three types of glaucoma:

• Open-angle glaucoma (OAG) is the most common form in the United States and Canada. (In other parts of the world, it’s less common.) It usually affects both eyes at the same time. Your vision gradually gets worse. But it gets worse so slowly that you may not notice it.
• Closed-angle glaucoma (CAG) isn’t very common in the U.S. and Canada. It usually affects one eye at time. CAG can happen suddenly and be a medical emergency.
• Congenital glaucoma is a rare form of glaucoma that some infants have at birth. Some children and young adults can also get a type of the disease.

The exact cause isn’t known. Experts think that increased pressure in the eye (intraocular pressure) may cause the nerve damage in many cases. But some people who have glaucoma have normal eye pressure.

Some people get glaucoma after an eye injury or after eye surgery. Some medicines (corticosteroids) that are used to treat other diseases may also cause glaucoma.

Pinkeye, also called conjunctivitis, is inflammation of the thin tissue lining the eyelids and the white part of the eye. Pinkeye is common among children, but may occur at any age. It is most often caused by a virus, which can be easily spread to other people. Other common causes of pinkeye include bacterial infection and allergies. One or both eyes may be affected. Pinkeye is usually mild and goes away within a few days with treatment.

Common symptoms of pink eye are mild redness, discharge, and itching. Sometimes, it feels like there’s something in the eye. Other symptoms of pink eye include:

• Eyelids stuck shut when you wake up in the morning (the classic symptom)
• Uncomfortable, thick yellow or green discharge (often a bacterial infection)
• Thin, clear drainage from the eye (often a viral infection or an allergic reaction)
• Itching, burning, or feeling like there’s sand in your eye
• Family member with the same symptoms (you are passing it from one person to another)
• A recent cold (often a viral infection)
• Swollen lymph nodes (often a viral infection)

Pinkeye has a number of different causes, including:

• Viruses
• Bacteria (such as gonorrhea or chlamydia)
• Irritants such as shampoos, dirt, smoke, and pool chlorine
• Allergies, like dust, pollen, or a special type of allergy that affects some contact lens wearers

Pinkeye caused by some bacteria and viruses can spread easily from person to person, but is not a serious health risk if diagnosed promptly. Pinkeye in newborn babies, however, should be reported to a doctor immediately, as it could be a vision-threatening infection.

Dry eye syndrome is a problem involving your tears. With this syndrome, your tear glands don’t make enough tears or your tears evaporate too fast.

This problem is more common in older adults and in those with certain diseases, such as diabetes, allergic conjunctivitis, or the autoimmune condition Sjögren’s syndrome.

Dry eye syndrome may go away with treatment. But for some people, it can be a lifetime problem and cause a lifetime nuisance.

Dry eyes can be caused by everyday things, like being outdoors in the wind and sun, staring at a computer screen, or just being tired. Being around cigarette smoke may also cause dry eyes.

In addition to an imbalance in the tear-flow system of the eye, dry eyes can be caused by situations that dry out the tear film. This can be due to dry air from air conditioning, heat, or other environmental conditions. Other conditions that may cause dry eyes are:

• The natural aging process, especially menopause
• Side effects of certain drugs such as antihistamines and birth control pills
• Diseases that affect the ability to make tears, such as Sjogren’s syndrome, rheumatoid arthritis, and collagen vascular diseases
• Structural problems with the eyelids that don’t allow them to close properly.

The usual symptoms are: eyes feeling itchy, scratchy, and irritated.