Cataract Treatment
Intraocular Lenses (IOLs)
How IOLs Work
An intraocular lens (IOL) is the artificial lens surgeons implant to replace the eye's crystalline lens that must be removed once it becomes cloudy. The main job of the IOL is to focus light onto the back of the eye (or retina), just as a natural, healthy eye lens would.
From here, the light rays are converted into electrical impulses that travel to the brain, where they are then converted into images. If the light isn't focused correctly on the retina, then the brain can't process the images accurately.
IOLs share the same basic construction as earlier versions—a round, corrective central portion of the lens with 2 arms, or haptics, to keep it in place in the eye—but other than these shared characteristics, modern IOLs can vary widely in ' design, being made of plastic, silicone, or acrylic.
Most of today's IOLs are about a quarter of an inch or less in diameter and soft enough to be folded so they can be placed into the eye through a very small incision.
Types of IOLs
The most common type of IOL is called a posterior chamber lens, meaning it is placed behind the iris within the capsule where the natural lens used to be. When it is placed in front of the iris, as might happen when the lens capsule is damaged, it is called an anterior chamber lens.
Here are some of the types of IOLs we offer at Highland Ophthalmology:
Commonly Used IOLs
- Monofocal IOLs, such as the Alcon® AcrySof® ReSTOR® IOL, provide a set focal point, usually for distance vision. This allows cataract surgery patients to see clearly within a range. About 95 percent of people who receive a standard IOL have their vision restored to its pre-cataract state.1 However, most patients still require glasses for reading or distance vision.
- Monovision is a technique the surgeon may choose to perform that involves inserting an IOL in one eye for near vision and an IOL in the other eye for distance vision. This technique requires adaptation, since each eye will then be oriented towards different needs.
Advanced Technology IOLs
- Multifocal IOLs, or advanced technology IOLs, are a newer type of lens that treats multiple focal points and reduces or eliminates the need for eyeglasses or contact lenses after cataract surgery. Part of the rapid evolution in IOL innovations, these newer lenses are made from cutting-edge materials with unique features. This is made possible through highly specialized optics that divide light and focus it on more than one point to provide a range from near to far eyesight. To read more about Multifocal IOLs, click here.
- Accommodative IOLs are considered monofocal, meaning they have a fixed focal point. This type of lens is designed to move in response to your eye's own muscle, which translates into the ability to see multiple focal points
While there are several advanced technology IOLs on the market today, the newer and most popular ones are made by Alcon®, such as the AcrySof® IQ ReSTOR® IOL.
Astigmatism Correcting IOLs
In addition to treating the cataract, some IOLs can also correct astigmatism at the time of surgery. These lenses will minimize the need for distance vision glasses after surgery. One such IOL that has gained widespread popularity is the Alcon® AcrySof® IQ Toric IOL (made specifically to address cataracts with astigmatism). To read more about Toric IOLs, click here.
No single lens works best for everyone. Only one of our surgeons can determine the most appropriate option for you and will work with you to help select the right course of treatment.
Also, read about Laser Refractive Cataract Surgery and Limbal Relaxing Incisions.
References
- "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.