The most common eye operation is for cataract surgery. This requires the removal of the clouded lens (cataract) and replacement with an artificial lens (intraocular lens implant – IOL). Because of modern advancements there is a large variety of artificial lens implants now available.
Depending on the patients’ visual needs and affordability, different lenses can be recommended.
There are a number of implants choices available. The BC government started to cover the cost of the standard soft FOLDABLE (acrylic) intraocular lens implant in 2012. This replaced the previous rigid plastic PMMA lens as standard of care in this province. Whereas before the old hard lens required stitches, and took longer to heal – now the soft lens allows everyone to heal much faster after cataract surgery.
These lenses come in a large variety, and generally can be classified under two categories: Aspheric Monofocal (Quality vision but still dependant on glasses afterwards) and Glass independence (Greater independence from glasses).
1. Aspheric Monofocal
This newer intraocular lens implant (AMO Tecnis 1 lens implant) is designed to minimize residual aberrations of the eye (glare and spherical aberration) that contribute to poorer contrast sensitivity and night vision. This has become the most highly recommended lens by ophthalmologists for their cataract patients. These implants have generally replaced the standard regular foldable lens.
2. Glass Independence
There are two reasons to require glasses after cataract surgery. One reason is to correct astigmatism, and the other is to correct presbyopia.
Astigmatism
Astigmatism is a common condition that may cause blurred vision. The distorted vision is caused due to the eye’s cornea or lens having an irregular shape. Generally more than 1/3 of patients require glasses to correct astigmatism. With the Toric Lens Implant this internal optical distortion of the eye can be neutralized. After surgery the patient will not need glasses except to read.
Presbyopia
Around the age of 45, most people begin to have difficulties changing the focus in their eyes from distant objects to near vision tasks such as reading. For those who have never worn glasses, they will now need to begin using reading glasses. Those who already wear glasses may choose to get bifocals (or no-line bifocals known as progressive lenses). A small percentage of people are fortunate to have the right amount of nearsightedness to allow them to read without their glasses, even though they need them to see in the distance. Until fairly recently, individuals who had cataract surgery had no real options in lens implants. Only monofocal (one focal distance) lenses were available. This means the eye can only focus at one distance.
Now, there are a few types of Multifocal Lens Implants available . These lenses offer a range of focusing distances rather than the single point of focus of traditional lenses. Most people are aware of bifocal glasses, or even progressive lenses (no-line bifocals). These types of glasses allow us to see distant and nearby objects in clear focus by looking through different parts of the lenses. When cataract surgery is done, a lens implant replaces the crystalline lens of the eye. It is now possible to use a multifocal lens implant. They are all made with concentric rings to enable focusing on near and far objects without having to adjust where you are looking. These are the best lenses to achieve reading vision but the “rings” can produce night halos which occasionally are noticeable with night driving.
BoydVision offers several different options for this type of implant: