An intraocular lens (or IOL) is a minute, artificial lens that is placed in the eye during a cataract operation. It replaces the eye’s natural lens that can become cloudy due to a cataract.
The lens refracts light rays that enter the eye which help you to see a clear image. If this lens is cloudy it is called a cataract which causes blurry, hazy and less saturated images. Cataract surgery is then performed to replace the cloudy lens with the IOL with the purpose to re-establish clear vision.
IOL’s are similiar to spectacles and contact lenses as they come in different focusing powers. Before the operation, the length of your eye will be measured and the necessary IOL power will be calculated.
What are IOL’s made of?
Majority of IOL’s are made of silicone or acrylic material. A coat on the IOL is present to protect your eyes from the sun’s harmful ultraviolet (UV) rays.
Type of IOL’s:
The most common type of IOL used is called a monofocal IOL. This implies it has one focusing distance thus providing clear near, intermediate or distance vision. Usually the IOL is set for distance vision and patients furthermore use reading glasses for near.
Some IOL’s have more than one focusing power within the same lens. These are called multifocal and accommodative lenses. These IOL’s reduce the necessity of spectacles as it provides you with clear vision for more than one distance.
These IOL’s provide both distance and near focus at the same time. The lens has different zones set at different powers. These lenses take some time to adapt as your brain has to learn to select the image that is focused.
Read more on multifocal IOL’s, such as the PanOptix here.
These lens moves or changes shape inside your eye, allowing focus at different distances.
For people with large amounts of astigmatism, there is an IOL called a Toric IOL. Astigmatism is a refractive error caused by an uneven curve in your cornea or lens which causes distortion of your view. This astigmatism is also correctable by contact lenses or spectacles. The toric IOL is designed to correct that refractive error while replacing the IOL.
It is important to discuss your visual needs and expectations with your ophthalmologist. He or she will then decide what option would best be suited for you.