An intraocular lens (IOL) is implanted in the eye after cataract surgery, during which the natural crystalline lens (an opaque natural lens is called cataract) is removed so as to provide optimal vision. These artificial lenses are safe, and have been in use for decades, and now, there are several kinds of lenses to choose from, including premium IOLs.
What are the different types of intraocular lens implanted after cataract surgery?
The two most common types of intraocular lens implanted after cataract surgery are:
Posterior chamber lenses, PCIOL: PCIOLs are placed in the natural position of the crystalline lens, over the residual posterior capsule and are the most commonly used lenses.
Anterior Chamber lenses, ACIOL: ACIOLs are placed on top of the iris, the brown part of the eye, only in case the posterior capsule of the lens is deficient or damaged, since it is not the physiological position of the natural lens.
What are the different types of posterior chamber intraocular lens implanted after cataract surgery?
The lenses used after any kind of phacoemulsification, microincision cataract surgery or femto second laser cataract surgery are the same. These lenses are collectively called premium IOLs. After conventional cataract surgery, which is a manual surgery, rigid, non-foldable lenses are sometimes used, but they are no longer the standard of care.
Premium IOLs are of two kinds: Monofocal Intraocular Lens and Multifocal lenses
What are Monofocal IOLs?
Monofocal lenses can only provide vision for one distance, either for far, or for near. After monofocal lens implantation, you will need reading glasses or sometimes even bifocals (in case of astigmatism), which are glasses for both distance and near.
The different types of intraocular lens implanted after cataract surgery include:
Aspheric IOLs: Traditional IOLs are spherical and have a uniform curvature along the circumference, unlike the natural lens. This results in some distortions called higher-order aberrations (HOAs). Aspheric IOLs are more like the natural lens of the eye, and result in fewer HOAs, better vision in low light, and more comfort during driving at night. These lenses are also preferred in patients with large pupils/
Toric IOLs: Toric IOLs are premium intraocular lenses that correct astigmatism also. Conventional IOLs cannot correct cylindrical power or astigmatism, and patients need to wear corrective glasses, or have another refractive surgery like astigmatic keratotomy, limbal relaxing incisions etcetera in for better vision. Toric IOLs can offer patients of astigmatism also freedom from glasses following cataract surgery.
What are Multifocal Lenses?
Multifocal IOLs enable acceptable vision for both near, intermediate and far distance, and mean that you don’t need glasses after cataract surgery for most activities. These can have certain side effects like glare and decrease in contrast sensitivity, but the newer models available have very few side effects. These lenses are more expensive than monofocal IOLs, but if you don’t want to wear glasses, these are the best option for you.
Which of the different types of intraocular lens should I choose for implantation after cataract surgery?
The final decision for choosing from different types of intraocular lens implanted after cataract surgery must be taken in consultation with your eye doctor after a comprehensive eye examination, and discussion about your eye health and vision needs. Usually, the eye doctor will recommend an aspheric lens for most patients, toric lens if you have an astigmatism of more than 1.5Diopters, and multifocal lenses if you do not want to wear glasses.