What is age-related macular degeneration (AMD)? Age-related macular degeneration (AMD) is a disease that causes blurring of your central vision. The blurring happens because of damage to the macula, a small area at the back of the eye. The macula helps you see the fine detail in things that your eyes are focusing on...

One symptom of Lyme disease is a red rash (called erythema migrans). The rash usually starts as a small red area and then expands over several days. The rash occurs at the site of the tick bite and usually gets bigger over time. Sometimes the rash clears in the center, so that it looks like a bull's-eye. About half the...

Retinitis pigmentosa is an inherited eye disease in which there is a breakdown of the nerve layer (retina) in the back of the eye. It can lead to blindness. Often the first sign of the disorder is an inability to see in low light and darkness (night blindness). Those affected usually develop a ring-shaped blind spot...

The slit lamp exam uses a tool that provides a magnified, three-dimensional (3-D) view of the parts of the eye. During the exam, your doctor can look at the front parts of the eye. These parts include the clear, outer covering (cornea), the lens, and the colored part (iris). The doctor can also see the front part of the...

What is optic neuritis? Optic neuritis is inflammation of the optic nerve, which lies at the back of the eye. This nerve carries visual information from the eye to the brain. If it's inflamed, you may have blurred or double vision or even loss of vision. What causes it? Your doctor may not know what caused this problem...

A cataract is a painless, cloudy area in the lens of your eye. A cataract blocks light from reaching the retina (the nerve layer at the back of the eye) and may cause vision problems. Cataracts are common in older adults and are linked to aging. Smoking and exposure to too much sunlight are other risk factors. Cataracts...

Has info on cataracts, glaucoma, and pinkeye. Also has links to age-related macular degeneration, vision tests, and a cataract surgery decision aid.

Briefly discusses causes of burns, including chemicals, UV light, hot steam, and flash fires. Offers interactive tool to help decide when to seek care. Also offers home treatment tips.

If you have narrow drainage angles or you have long-term (chronic) closed-angle glaucoma, you may need to avoid medicines that widen (dilate) the pupil, the dark spot in the center of the eye. Having wide pupils when you have these other problems may cause acute closed-angle glaucoma. This is a dangerous condition that...

Floaters are shadows or dark objects that "float" across your field of vision. Floaters may appear as dark specks, strings, or cobwebs that float through the eye. Many people begin to see floaters as they get older and their eyes age. If floaters have been present before, or if they occur with a diagnosed migraine...

An Amsler grid is a chart with horizontal and vertical lines that form boxes. It has a dot in the center. An Amsler grid is one of the easiest ways to screen for age-related macular degeneration (AMD). Your doctor may give you an Amsler grid to use at home. If you usually wear reading glasses, put them on, and place the...

Vision tests check many different functions of the eye. Some of the tests measure your ability to see details at near and far distances, check for gaps or defects in your field of vision, and evaluate your ability to see different colors. Others may check how sensitive you are to glare (brightness acuity), how well your...

Briefly discusses causes of pinkeye (conjunctivitis). Covers symptoms like red eyes and itching or burning feeling. Offers interactive tool to help decide when to seek care. Also offers home treatment tips.

Severe dehydration means: Your mouth and eyes may be extremely dry. You may pass little or no urine for 12 or more hours. You may not feel alert or be able to think clearly. You may be too weak or dizzy to stand. You may pass out. Severe dehydration is a medical emergency and requires emergency treatment. Call or other...

Diabetes damages small blood vessels throughout the body. Diabetic retinopathy happens when prolonged high blood sugar damages the blood vessels of the retina. This is the part of the eye that sends images to your brain. Other conditions that increase your risk include high blood pressure, high cholesterol, and kidney...

Here are some examples of when IOLs may be used. To replace a lens after cataract surgery Surgery for cataracts involves removing the natural lens of the eye that contains the cataract. The lens may be replaced with an artificial lens called an intraocular lens implant (IOL). Or you may wear eyeglasses or contact lenses...

Genes are the part of a body cell that contain the biological information that parents pass to their children. Genes control the growth and development of cells. Genes are made of DNA (deoxyribonucleic acid), a substance inside the center (nucleus)

Sjögren's syndrome (say "SHOH-grins") causes your body's defense, or immune, system to attack the glands that make moisture. The condition affects your tear and saliva glands and sometimes other parts of your body. Your eyes and mouth get very dry. Sjögren's also may cause you to be very tired and to have pain in your...