Eye Smart Health Information
Amblyopia is poor vision in an eye that did not develop normal sight during early childhood. It is sometimes called “lazy eye.”
When one eye develops good vision while the other does not, the eye with the poorer vision is called amblyopic. Usually, only one eye is affected by amblyopia, but it is possible for both eyes to be “lazy.” This condition is called bilateral amblyopia.
The condition is common; approximately two or three out of every 100 people has amblyopia. The best time to correct amblyopia is during infancy or early childhood.
Bacterial Keratitis (Corneal Ulcer)
Bacterial keratitis is an infection of the cornea (the clear, round dome covering the eye’s iris and pupil) that causes pain, reduced vision, light sensitivity and tearing or discharge from your eye. Resulting from infection from contact lens use or from injury to the eye, bacterial keratitis usually develops very quickly, and if left untreated, can cause blindness.
Blepharitis is a common and ongoing condition where the eyelids become inflamed (swollen), with oily particles and bacteria coating the eyelid margin near the base of the eyelashes. This annoying condition causes irritation, itchiness, redness, and stinging or burning of the eyes. While the underlying causes of blepharitis aren’t completely understood, it can be associated with a bacterial eye infection, symptoms of dry eyes or certain types of skin conditions such as acne rosacea.
Cataract is a clouding of the eye’s lens. When we look at something, light rays travel into our eye through the pupil and are focused through the lens onto the retina, a layer of light-sensitive cells at the back of the eye. The lens must be clear in order to focus light properly onto the retina. If the lens has become cloudy, this is called a cataract.
Conjunctivitis (Pink Eye)
Conjunctivitis is the term used to describe swelling (inflammation) of the conjunctiva — the thin, filmy membrane that covers the inside of your eyelids and the white part of your eye (known as the sclera). Often this condition is called “pink eye.”
The conjunctiva, which contains tiny blood vessels, produces mucus to keep the surface of your eye moist and protected. When the conjunctiva becomes irritated or swollen, the blood vessels become larger and more prominent, making your eye appear red. Signs of pink eye may occur in one or both eyes.
Detached or Torn Retina
The retina is the light-sensitive tissue lining the back of our eye. Light rays are focused onto the retina through our cornea, pupil and lens. The retina converts the light rays into impulses that travel through the optic nerve to our brain, where they are interpreted as the images we see. A healthy, intact retina is key to clear vision.
Diabetic retinopathy, the most common diabetic eye disease, occurs when blood vessels in the retina change. Sometimes these vessels swell and leak fluid or even close off completely. In other cases, abnormal new blood vessels grow on the surface of the retina.
The retina is a thin layer of light-sensitive tissue that lines the back of the eye. Light rays are focused onto the retina, where they are transmitted to the brain and interpreted as the images you see. The macula is a very small area at the center of the retina. It is the macula that is responsible for your pinpoint vision, allowing you to read, sew or recognize a face. The surrounding part of the retina, called the peripheral retina, is responsible for your side — or peripheral — vision.
Dry Eye (Lubrication Deficiency)
When you blink, a film of tears spreads over the eye, making the surface of the eye smooth and clear. Without this tear film, good vision would not be possible. Sometimes people don’t produce enough tears or the right quality of tears to keep their eyes healthy and comfortable. This condition is known as dry eye.
Floaters and Flashes
You may sometimes see small specks or clouds moving in your field of vision. These are called floaters. You can often see them when looking at a plain background, like a blank wall or blue sky. Floaters are actually tiny clumps of cells or material inside the vitreous, the clear, gel-like fluid that fills the inside of your eye.
Glaucoma is a disease that damages your eye’s optic nerve. It usually happens when fluid builds up in the front part of your eye. That extra fluid increases the pressure in your eye, damaging the optic nerve.
It is estimated that three million Americans have glaucoma, but only about half of them know that they have glaucoma. Glaucoma is a leading cause of blindness for people over 60 years old. But blindness from glaucoma can often be prevented with early treatment. When glaucoma develops, usually you don’t have any early symptoms and the disease progresses slowly. In this way, glaucoma can steal your sight very gradually. Fortunately, early detection and treatment (with glaucoma eyedrops, glaucoma surgery or both) can help preserve your vision.
Low vision is a loss of eyesight that makes everyday tasks difficult. A person with low vision may find it difficult or impossible to accomplish activities such as reading, writing, shopping, watching television, driving a car or recognizing faces.
When vision cannot be improved with regular eyeglasses, medicine or surgery, people with low vision need help to learn how to make the most of their remaining sight and keep their independence. Losing vision does not mean giving up your activities, but it does mean finding new ways of doing them.
Age-related macular degeneration (AMD) is a deterioration or breakdown of the eye’s macula. The macula is a small area in the retina — the light-sensitive tissue lining the back of the eye. The macula is the part of the retina that is responsible for your central vision, allowing you to see fine details clearly.
The macula makes up only a small part of the retina, yet it is much more sensitive to detail than the rest of the retina (called the peripheral retina). The macula is what allows you to thread a needle, read small print, and read street signs. The peripheral retina gives you side (or peripheral) vision. If someone is standing off to one side of your vision, your peripheral retina helps you know that person is there by allowing you to see their general shape.
Ptosis is a drooping of the upper eyelid. The lid may droop only slightly, or it may cover the pupil entirely. In some cases, ptosis can restrict and even block normal vision. It can be present in children as well as adults and may be treated with surgery.
If a child is born with ptosis, it is called “congenital ptosis.” Congenital ptosis is often caused by poor development of the muscle that lifts the eyelid, called the levator muscle. This condition usually doesn’t improve on its own over time. With moderate to severe congenital ptosis, the child may need treatment to have his or her vision develop normally.
Tearing is excessive production of tears.