Intraocular Lenses - Frequently Asked Questions

Developed by a British ophthalmologist after World War II, the intraocular lens (IOL) is now used throughout the world to help patients overcome the decline of vision generally associated with age. On this page we answer some commonly asked questions about intraocular lenses to help you understand their function and decide if the procedure is right for you.

What are intraocular lenses?

Intraocular lenses are tiny lenses made of a synthetic material that are implanted in the eye to replace the eye's natural crystalline lens when it becomes clouded with cataracts, or has grown inflexible with age and can no longer focus for near-vision tasks, a condition known as presbyopia.

Most patients today are treated with foldable intraocular lenses. A foldable IOL is made of silicone or an acrylic that can be rolled or folded for insertion. A hard IOL is made of a rigid plastic material. Hard intraocular lenses are used for specific cases when the ophthalmologist feels they will provide better results than foldable IOLs. Since hard lenses cannot be folded, they require a larger incision for insertion. Both types of intraocular lenses are typically used to address vision problems that cannot be corrected with LASIK, although LASIK is sometimes used to enhance the results of an IOL procedure.

What is the difference between ICLs and IOLs?

The greatest difference between the ICL (implantable contact lens) and the IOL (intraocular lens) lies in function. The ICL is implanted over the eye's natural crystalline lens. Rather than act as a substitute for the natural lens, an ICL enhances its acuity, much as glasses or contact lenses do. As such, ICLs are used to treat conditions such as myopia, hyperopia, and astigmatism and are recommended for adults aged 21 to 45. ICLs are sometimes called phakic IOLs, which can lead to confusion.

An IOL completely replaces the eye's natural crystalline lens. When cataracts form on the eye's natural crystalline lens and impair vision, the most effective solution is to replace the eye's natural lens with an intraocular lens. The ophthalmologist completely removes the crystalline lens and inserts an IOL to act as a substitute. The IOL procedure is also used to treat presbyopia, the gradual decline of near vision that typically begins as a person enters middle age. IOLs are used to treat patients aged 21 to 80.

What is the difference between multifocal and monofocal intraocular lenses?

Monofocal intraocular lenses provide good vision correction for one distance, generally far vision. After having a monofocal IOL procedure, reading glasses are still necessary. Some patients who select monofocal IOLs, however, compensate for both near and far vision by choosing to have one eye corrected for distance vision and one eye corrected for near vision. Multifocal intraocular lenses provide vision correction at all distances. Multifocal intraocular lenses improve near vision in addition to far vision and thus are an effective treatment for presbyopia as well as cataracts. Your ophthalmologist can help you decide the type of IOL best suited to your needs.

What does the IOL procedure involve?

The intraocular lens surgery procedure is a relatively quick outpatient procedure, taking less than an hour. Using a method that varies with the type of cataract surgery performed, the ophthalmologist first removes the natural crystalline lens of your eye. Then the IOL is inserted through a small incision into the space previously occupied by the crystalline lens. The incision is small and heals quickly. No stitches are necessary once the lens is in place. Only a local anesthetic is necessary for the procedure, and discomfort is minimal. Once the procedure is complete, a companion drives you home for a short recovery period.

Are intraocular lenses safe?

Intraocular lenses have undergone extensive research and testing in Europe, Asia, and the United States and have been proven safe for the treatment of cataracts and refractive errors. In the United States, the FDA subjected IOLs to stringent testing before granting approval. Millions of procedures to implant intraocular lenses have been successfully performed worldwide. As with any surgical procedure, there are some risks involved with IOL surgery, but they are minimal and affect only a small percentage of patients.

Are both eyes treated at the same time?

The ophthalmologist will typically treat one eye at a time, with a three-week interim between procedures. However, this varies with each patient and each doctor.

Will I feel the IOL after the procedure?

No, your eye will feel as it did before the procedure. In addition, the IOL will not be visible except to a trained ophthalmologist.

What results should I expect after IOL treatment?

Among the benefits of IOL treatment, you can expect good to excellent vision correction after IOL treatment. In FDA and other tests, with multifocal IOLs more than 80 percent of patients achieved distance and intermediate vision improvement of 20/25 or better, and more than 70 percent achieved 20/30 or better for near vision.

Who is a good candidate for IOLs?

Although IOLs are contraindicated for individuals who have particular medical conditions, most people between the ages of 21 and 80 who are suffering from cataracts or presbyopia and have healthy eyes are good candidates for intraocular lenses.

How do I find a doctor in my area?

Intraocular lenses are an excellent choice if presbyopia or cataracts are causing you vision difficulties. Use DocShop's convenient online listings to find a qualified ophthalmologist in your area and learn more about the IOL procedure or schedule an appointment.