What is nearsightedness?
Nearsightedness (myopia) is a vision condition in which you can usually see close or near objects clearly, but cannot see distant ones as clearly.

What is farsightedness?
Farsightedness (hyperopia) is a vision condition in which distant objects are usually seen clearly, but close ones appear blurred.

What is astigmatism?
Astigmatism is a vision condition in which light entering the eye is unable to be brought to a single focus, resulting in vision being blurred at all distances. (See our "Astigmatism" page for further information)

What is presbyopia?
Presbyopia is a vision condition that occurs when the crystalline lens of the eye gradually loses its ability to bring close objects into clear focus. It usually becomes noticeable when you reach your early-to-mid-forties and is a natural part of aging.

How are these vision conditions treated?
Nearsightedness, farsightedness, astigmatism and presbyopia are all treated with eyeglasses or contact lenses. In recent years, a number of options to surgically alter the shape of the cornea, the clear front surface of the eye, to correct nearsightedness and low to moderate astigmatism have been developed. These include radial keratotomy (RK) and photorefractive keratectomy (PRK). There is also a procedure called orthokeratology which uses a series of rigid contact lenses to provide improved vision for significant periods of time for some people with nearsightedness or astigmatism. Your doctor of optometry can help you decide if these options are right for you.

What is amblyopia?
Amblyopia (lazy eye) is the loss or lack of the full development of vision in one eye that is not fully correctable with lenses and is not the result of any identifiable eye health problem. Amblyopia is usually due to conditions such as crossed-eyes (strabismus) or a large difference in the refractive error between the two eyes.

How is amblyopia treated?
In young children, patching the good eye may help the amblyopic eye to improve. In addition, to help improve vision function, vision therapy techniques may be used. Eyeglasses or contact lenses may be prescribed to correct any refractive errors.

What are crossed-eyes?
Strabismus (crossed-eyes) is a vision condition in which your eyes are not properly aligned with each other. One or both eyes may alternately turn in (esotropia), out (exotropia), up (hypertropia) or down (hypotropia).

How are crossed-eyes treated?
Treatment of crossed-eyes often includes use of eyeglasses, prisms and vision therapy. In some cases, surgery may be needed.

What is glaucoma?
Glaucoma is a disease in which the fluid pressure in your eyeball increases and damages the optic nerve. This damage can cause severe vision loss and even blindness, if untreated.

How is glaucoma treated?
Glaucoma can generally be effectively controlled with prescription eye drops or other medicines which reduce the pressure in the eye. In some cases, laser procedures or surgery may be needed.

What are cataracts?
If the normally clear lens in your eye becomes cloudy, it is called a cataract. As the lens becomes cloudy, vision becomes blurred and/or distorted.

How are cataracts treated?
Eyeglasses or contact lenses can be prescribed to provide clearer vision until cataracts develop to the point that they impair vision. Then they need to be removed surgically.

During this surgery, an intraocular lens is usually implanted to replace your natural cloudy lens. In addition, contact lenses or eyeglasses are often still needed to fully restore vision.