Types of Eye Problems

The eyes are complex organs, with many parts that must work together to produce clear vision. Here is a basic overview of eye anatomy:

Cornea

This is a layer of clear tissue at the front of the eye that helps focus light.

Tear Ducts

Located at the corner of each eye, tear ducts produce tears to keep the cornea lubricated and clear of debris.

Iris & Pupil

The colored part of the eye is the iris. It is a muscle that controls the pupil, the opening in the middle of the eye that controls the amount of light coming in.

Lens & Retina

The lens is behind the pupil and focuses light onto the retina, the light-sensitive cells on the back of the eyeball. Acting much like the film in a camera, the retina converts images into electrical signals that are sent to the optic nerve.

Optic Nerve

The optic nerve is a thick bundle of nerve fibers attached to the back of the eye that transmits visual information from the retina to the brain.

When Things Go Wrong

Problems or malfunctions in any of eye parts cause many common eye conditions.

Refractive Errors

When light is not focused properly, it causes blurry vision. Refractive errors can usually be corrected with glasses, contacts, or surgery. They include:

• myopia (nearsightedness), which is when far-away objects look blurry;
• hyperopia (farsightedness), which is when close-up objects look blurry
• astigmatism, which can result in blurry vision because the cornea is not perfectly shaped to direct light into the eye.
• presbyopia, which is the inability of older people to focus on close-up objects.

Glaucoma

Glaucoma is increased pressure of the fluid inside the eye, which can cause optic-nerve damage. Glaucoma is a common cause of blindness, particular in diabetic patients.

Cataract

Cataract is a clouding of the lens, causing blurry or color-tinted vision. People with cataracts often report ‘haloes’ surrounding objects that they are looking at, particularly at night. It is most common in older people, and cataracts can be removed by surgery that replaces the lens with an artificial lens.

Age-related Macular Degeneration

Age-related macular degeneration (AMD) is gradual damage to the cells of the macula, most common in people over 60. It causes blurry vision, especially in the center of the field of view. AMD in the leading cause of blindness among people over age 55 in the United States

Amblyopia

Commonly referred to a "lazy eye," amblyopia occurs when one eye has worse vision than the other, and the brain begins to favor the better eye. This will occur if one of the eyes is blocked from producing clear images during the critical years from age 0-6. One eye may be inhibited by problems like a lid droop, tumor, or crossed eyes (‘strabismus’) that are not fixed when a child is young. It is crucial to have young children evaluated by an eye doctor to ensure that subtle signs of amblyopia are not present.

Diabetic Retinopathy

Diabetic retinopathy is damage to the blood vessels of the retina caused by diabetes. It causes blurred or dark spots in the field of vision and will eventually lead to blindness. The best way to avoid these vision problems is to keep your blood sugars under control and see your eye doctor every year for a dilated eye exam.

Retinal Detachment or Tear

A tear in or detachment of the retina causes blurry vision or partial loss of vision.

Dry Eye Syndrome

Dry eye is a lack of proper tears, usually due to a problem with the tear ducts or eyelids, or certain medications. It can cause pain and blurry vision.