How does cataract surgery work, and why do you need an intraocular lens afterwards?
A cataract is a clouding of the natural lens of the eye. The lens is a structure tucked away inside the eye that helps us focus our vision on near and far objects. The natural lens is initially clear when we are young, but can become cloudy as we age.
Cataract removal involves removing the cloudy natural lens of the eye and replacing it with a clear artificial lens, called an intraocular lens (IOL). Once the IOL is fitted to your eye, it cannot be changed without additional surgery.
What types of intraocular lenses (IOLs) are available?
As you prepare for cataract surgery, you will discuss your IOL options with your eye surgeon. Several different types of IOLs are available.
What is a standard IOL?
Standard IOLs are included in the cost of cataract surgery in most health insurance plans. These IOLs are of good quality and come in various powers. Your Ophthalmologist will work with you to determine the power you need.
These lenses are monofocal IOLs (also called single-focus IOLs). They provide the sharpest focus at one specific distance - usually long distance which is useful for driving. When you want to see up close for reading, or at a medium distance for using a computer, you need to wear glasses.
Patients with astigmatism will most likely need glasses all the time after cataract surgery, if they choose a standard IOL.
What is a premium IOL?
Premium IOLs are designed to provide freedom from glasses after cataract surgery. These IOLs use advanced technology to correct abnormalities in the eye and help you see better at close range.
There are several different types of premium IOLs:
- Toric IOLs. Toric IOLs are single-focus lenses designed for people who have astigmatism.
- Accommodative IOL. Accommodative IOLs use your eye muscles to adjust their focusing power and allow you to see clearly at closer distances. While these lenses often work well initially, they sometimes become less effective over time and have been linked to other problems - such as tilt or blur - that require additional procedures.
- Multifocal IOLs. Multifocal IOLs have more than one focusing power within each lens (similar to bifocal glasses, but without the lines or distortion). Multifocal IOLs are designed to help you focus at long distances, medium distances (for using computer screens), and close distances (for reading) without the need for glasses. Multifocal IOLs work well in daylight. In the dark, multifocal IOLs can make you see halos around lights. This can cause glare and interfere with night vision.
- Extended depth of focus IOLs (EDOF). EDOFs are similar to multifocal IOLs, but with less focusing power - and fewer side effects. Glare and halos are less of an issue with EDOF lenses, but their focusing power is not very strong either. Besides providing good distance vision, they can also help you focus at intermediate distances (for viewing computer screens), but you will still need glasses for reading.
Choosing between standard and premium IOLs for cataract surgery
You should work closely with your ophthalmologist to choose your IOL. There are many factors to consider.
Why choose a standard IOL?
Standard IOLs are cheaper, reliable, and don't have many side effects - but most people still need to wear glasses to see clearly at closer distances.
People choose standard IOLs when they:
- Wanting the cheapest option
- Prefer to avoid side effects such as glare and halos around lights
- Don't mind wearing glasses
- Have other eye conditions, such as dry eye, glaucomaglucoma, or macular degeneration, which may interfere with the precision technology used in premium IOLs
Why choose a premium IOL?
Premium IOLs offer the freedom of glasses, but they are more expensive and sometimes take time to adjust to and can be uncomfortable for some time.
People choose premium IOLs if they:
- No other eye problems
- Do not mind the additional costs that must be incurred