What to know before undergoing lens replacement surgery
Lens replacement surgery is a procedure that removes the eye's natural but dysfunctional lens and replaces it with an artificial lens to improve vision. There are several types of replacement (intraocular) lenses to choose from.
What is lens replacement surgery?
Lens replacement surgery is where the natural crystalline lens of the eye is replaced with an artificial lens implant, also known as an intraocular lens.
Ongoing research and development into the types of intraocular lens (IOL) implants has led to widespread use of new-generation trifocal IOLs. This new lens is designed to allow you to see objects clearly at a distance as well as close up.
The procedure itself is very well established and is exactly the same as a cataract operation, which has been widely performed worldwide since the 1950’s. When a patient develops a cataract, their natural lens becomes cloudy and hazy. When this clouding affects the vision, it becomes necessary to remove the clouded lens and replace it with a clear lens implant.
Lens replacement surgery is the exact same procedure, except the lens doesn’t need to have developed a cataract. The bonus of lens replacement is that, as well as offering correction of vision, it ensures that you will never develop cataracts in the future, meaning you can enjoy the rest of your life glasses-free.
Is lens replacement surgery safe?
Lens replacement surgery is an outpatient procedure and takes less than approximately 20 minutes to perform. It is considered to be one of the safest and most effective types of surgery.
The procedure involves making a micro-incision in the very periphery of the cornea, through which the natural lens is removed and replaced with a bespoke intraocular lens implant. There is no need for stitches due to the micro-incision being so small that it is self-healing.
What are the different types of replacement lenses?
Monofocal lenses
These aim to correct vision and minimise dependence for glasses at a single focal point. Monofocal lenses can only correct farsightedness (hyperopia) or short-sightedness (myopia) but never both at the same time. The majority of people have their focal point set for distant vision, which would mean they will need glasses for intermediate and near vision.
Toric monofocal lenses
Monofocal lenses can achieve the best possible unaided vision for the target focal point, provided that the shape of the cornea is spherical. This means that the curvature of the eye is similar in all directions. Some eyes are shaped more like a rugby ball, and so a simple monofocal lens cannot address the asymmetrical shape of the cornea. In this situation, a premium monofocal toric lens may be an option to reduce the oblongness (astigmatism) of the eye. You will still need glasses for intermediate and near vision if the post-op target was to correct distant vision.
Extended depth of focus lenses (EDOF)
A premium lens which works by creating a single elongated focal point when light enters the eye and enables you to focus at a continuous range of distances (intermediate and near vision) unaided. EDOF lenses tend to cause less glare/halo effect when compared to multifocal trifocal lenses; however, near vision can be less clear when compared to a multifocal lens and you may need glasses to manage some tasks at near vision. These lenses are also available in the toric range, if astigmatism correction is required.
Multifocal trifocal lenses
A premium lens which aims to correct your vision and reduce your dependence on glasses for multiple distances, far, intermediate and near vision. They work by splitting light that enters your eye in more than one focal point, allowing you to switch between far, intermediate and near vision. Unfortunately, there are potential side effects (e.g., halos, glare, reduced contrast). These must be explored in detail at your consultation to ensure that this lens will suit your needs. They are also available in toric range if astigmatism needs to be corrected.
How is the recovery after lens replacement surgery?
Patients are usually advised to take 2-3 days off work immediately after the procedure. Patients are normally able to see fairly well the day after surgery; it does take a few weeks for the vision to fully settle with intraocular lens implants (IOLs). This is a combination of healing and adaptation to the IOLs.
You will be able to perform most of your day-to-day tasks immediately after surgery without any difficulty, but strenuous physical exercise or activities should be restricted in the weeks following surgery.
