Cataract Surgery FAQs

Because cataract surgery is an important decision that involves your eyes and your vision, you're bound to have questions. Make sure to discuss any questions you have with the doctor who will perform your procedure. This is the best way to get clear, candid answers that apply specifically to your vision and the cataract procedure you are considering.

For general information, we've listed many of the questions people commonly ask about cataract surgery. The questions cover everything from "Will it hurt?" to "How much does it cost?"

Just click on one of the following topics to get started. If you don't see your question or topic addressed here, check with your doctor.

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What is a cataract?

Contrary to popular belief, a cataract is not a "film" over the eye. Rather it is a gradual thickening of the lens that causes the lens to become so clouded that light is either distorted or cannot reach the back of the eye (the retina)   Retina: The transmitter located at the back of your eye that sends the images to your brain.   for transmission to the brain.

What are the symptoms of cataracts?

Blurry or dim vision, colors appearing faded, poor night vision, halos appearing around lights, and sensitivity to bright lights can all be symptoms of a cataract. Age-related cataracts develop very slowly and painlessly. In fact, you may not even realize that your vision is changing until you find yourself going to the eye doctor seeking a change in your eyeglass or contact lens prescription.

What causes cataracts?

Many things can cause a cataract to form, the most common being the natural aging process. As the lens of your eye ages, it gradually thickens and yellows, eventually becoming so cloudy that you are said to have a "cataract." Other diseases, like diabetes   Diabetes: A disease in which the body does not produce enough, or properly use, the hormone insulin. Most Americans who are diagnosed with diabetes have Type 2 diabetes.   and glaucoma,   Glaucoma: An eye disease that develops when too much pressure inside the eye damages the optic nerve due to the slow drainage of eye fluid through the eye's trabecular meshwork. Without treatment, glaucoma can cause permanent blindness within just a few years. Symptoms include halos around lights, tunnel vision and vision loss. Glaucoma is most often treated with medications designed to reduce intraocular pressure.   can increase the chances that a person will develop cataracts. Eye injuries and chronic use of corticosteroids   Corticosteroids: A class of steroid hormones used to treat a variety of conditions. Chronic use may lead to the formation of posterior subcapsular cataracts.   can cause cataracts as well. For more information on what causes cataracts, click here.

How does a cataract form?

The lens of the eye can change in multiple ways, all resulting in the condition called a cataract. In general, there are 2 ways a cataract can form—at the nucleus, or center, of the lens, or at the cortex, or shell, of the lens.

Are there different types of cataracts?

Yes, there are several types of cataracts. The different types are defined by which part of the lens they affect. Nuclear cataracts are the most common and usually form as a natural part of the aging process as cells from the lens deposit in the nucleus of the lens. Cortical cataracts   Cortical Cataract: A cortical cataract occurs when the transparency of the cortex surrounding the nucleus is compromised. Cortex means "shell." While not as common as nuclear cataracts, cortical cataracts are fairly common and are caused by the natural aging process.   are also fairly common and form when the shell, or cortex, of the lens becomes hard. Read more about types of cataracts.

Is there anything I could have done, or do, to prevent cataracts from forming?

No. Since developing cataracts is a natural part of the aging process, it is highly unlikely that you can prevent their development. There are things you can do to slow down their development, however, such as:

  • Wear sunglasses. Look for a label from the American National Standards Institute (ANSI) that says that the lenses block both UVA and UVB rays
  • Eat a diet rich in antioxidants

Why do my cataract symptoms differ from someone else's?

There are multiple types of cataracts, and even within the same type, there are a range of symptoms a person can experience.

Is developing a cataract an inevitable part of aging?

Yes. If you live long enough, you will likely develop cataracts.

Do certain diseases or conditions make a person more likely to develop cataracts?

Yes. Diabetes and glaucoma both predispose a person to developing cataracts. For more on cataracts and other eye conditions, click here.

Can cataracts increase the chances that I will develop another eye condition?

Because a cataract affects the part of the eye that is responsible for refracting light, it will sometimes cause a refraction error such as nearsightedness or farsightedness. And rarely, if left to mature, a cataract can eventually become so large that it causes a type of glaucoma.

Is presbyopia related to cataracts?

No. As the natural lens of the eye ages, it often hardens and is less able to flex and focus light. This hardening is often accompanied by a loss of flexibility in the surrounding muscles. This hardening and loss of flexibility is commonly called presbyopia. Because presbyopia is a function of aging, many people with cataracts also have presbyopia. In recent years, multifocal intraocular lenses have been developed to correct both cataracts and presbyopia simultaneously.

Can cataracts spread from one eye to the other?

No. However, a person can develop cataracts in both eyes.

Can I go blind from cataracts?

Yes. When left untreated, cataracts may eventually cause blindness.

What does it mean when someone says a cataract is "ripe?"

This is a colloquial way of saying that the cataract affects vision enough that the benefits of removing it outweigh the risks of the surgical procedure.


  1. "The Aging Eye: A Special Health Report from Harvard Medical School," Ed. Fine, Laura C., M.D, and Heier, Jeffrey S., M.D., copyright 2006, Harvard Health Publications, Boston, MA.
  2. AcrySof® IQ ReSTOR® IOL (Model SN6AD1). Directions for Use.