Artificial or man-made intraocular lenses, or IOL implants, replace the eye’s natural lens that becomes cloudy or opaque due to Cataract. Cataract Surgery involves the removal of the opaque lens and replacing it with an IOL implant. Generally IOLs are made of flexible and foldable acrylic material. IOLs come in various numbers and the right number for a particular person is calculated to give the best vision when implanted in the eye.
Types of IOL implants
The surgical removal of lens from the eye mandates its replacement with an artificial lens that not only fills its position but also focus light in a better way to give clear vision. This artificial lens is implanted almost at the original position of the removed natural lens to restore as much vision as possible. It is a permanent procedure and generally does not require any maintenance. Once implanted it remains for life.
Depending upon the need and the refractive status of the patient, a variety of IOLs are available:
- Monofocal lens: It is the most common type of lens implanted by ophthalmologists and preferred by patients. The lens can provide best vision either for far or near. The other vision (distance or far) will need spectacles for clear vision. E.g. if a patient chooses to have clear distant vision, then spectacles or reading glasses will be required for near activities and vice versa. The patient may chose to get one eye corrected for distance vision and the other for near vision. This is called “monovision.”
- Multifocal or accommodative lenses: This is a fairly new type of IOL that reduces dependency on glasses and in some cases eliminates the need of glasses. The multifocal lens is designed with a series of focal zones or rings that facilitates focus of light for distance, intermediate and near. The Accommodative lens is similar but works on a slightly different principle.
- Toric IOL: It is an astigmatism correcting lens. Astigmatism leads to distorted or blurred near and distant vision because of the shape of the cornea. Toric lens can be monofocal (single vision correcting) or multifocal (distant, intermediate and near vision correcting).
Which type of IOL implant is right for you?
- The Ophthalmologist will examine your eye to evaluate the IOL prescription that will be best suited for you. The surgeon prefers to discuss the options with the patient so that a more comfortable visual result can be achieved.
- The choice of IOL also depends upon the whether the patient wants to be glass free or otherwise.
- Astigmatism correcting IOLs are ideal for people with astigmatism of 1.5 or more to be able to see clearly.
- Glasses or contact lenses may still be required in some cases.