Until fairly recently, nearly everyone who had cataract surgery was fitted with a standard intraocular, or monofocal, lens. Monofocal lenses allow you see objects in the distance clearly but require that you wear glasses to see objects that are closer. However, recent advancements in lens technology have made it possible to not only treat the cataract but reduce or eliminate dependence on glasses as well.

The type of IOL you need depends on your particular situation. Your doctor will work with you to determine which lens is best for you.

There are four basic types of intraocular lenses (IOLs).

Monofocal Lenses, also known as standard lenses, provide clear vision but only at one fixed focal point, usually at a distance. If you are fitted with a monofocal lens, you will most likely need glasses to see up close.

Multifocal Lenses have special features that correct your near, intermediate, and distance vision in the same lens. Multifocal IOLs provide your best chance at being free of glasses for the majority of activities. Learn more about how an multifocal IOL works.

For an example of a multifocal lens, visit www.acrysofrestor.com.

Accommodative Lenses. Accommodative lenses, also known as variable focus lenses, are designed to move in response to your eye muscles to adjust for near, immediate and far vision. Those who are able to retrain their eye muscles to move the lens have experienced relief from presbyopia as well as cataracts. (See How the Aging Eye Works for more detail on how the eye's muscles flex the lens.) However, accommodative lenses actually have a fixed focal point, which makes them a type of monofocal lens.

Toric Lenses. Toric lenses are designed for people with astigmatism, reducing or virtually eliminating the need for glasses for distance vision following surgery in people with astigmatism.

Each of these types of lenses can have additional attributes. For example, there are IOLs that are multifocal, aspheric, and blue light filtering.

IOLs that are also aspheric correct spherical aberration, which is a change in curvature between the center and edge of the pupil. Spherical aberration causes multiple focal points and thus blurry vision. Some aspheric IOLs are slightly flatter and have also been shown to improve contrast, and make it easier to see in varying lighting conditions.

Many IOLs are also now light-filtering. Ultraviolet (UV) rays have long been suspected as a contributor to cataracts. High-energy blue light also may cause damage to the retina and play a role in the onset of age-related macular degeneration. Many IOLs now filter these potentially harmful rays, present in natural and artificial light. For more about lenses that filter both UV and blue light, visit www.acrysofrestor.com.

No single lens works best for everyone. Only your ophthalmologist can determine the most appropriate option for you and will work with you to help you select the right course of treatment. See Choices to be Made to understand more about the factors your doctor will ask you to consider.

Not everyone is a good candidate for an IOL, either. If you had cataract surgery before replacement lenses were available, or you are considered a poor candidate because of additional eye diseases or conditions, you may need to be fitted with special contact lenses or require another treatment option instead.