Cataract surgery is a common procedure that involves the removal of the eye's natural lens, which has become cloudy due to age or injury, and replacing it with an artificial lens. The most commonly used lens for this procedure is called a monofocal intraocular lens (IOL). This type of lens is designed to focus for close, mid-range, or distance vision. It is composed of a round lens fused with two plastic haptic elements that are shaped like curved cables.
These haptics act like tension-charged springs to automatically center the lens inside the ocular compartment where they are implanted. Unlike transplanted organs, there is no shortage of tissue and no chance of rejection when it comes to intraocular lenses. The term implant is used because the artificial lens is placed surgically and permanently inside the eye. In the past, removing a cataract meant that the patient had to wear cataract glasses or contact lenses.
However, with the introduction of IOLs, patients can now enjoy improved vision without the need for corrective eyewear. Standard monofocal lenses are generally used to replace the power of lenses removed during cataract surgery. However, newer premium lenses are now available that are designed to correct astigmatism or presbyopia and make people less dependent on glasses. The decision to place a high-quality intraocular lens, rather than a standard lens, depends on patient preferences and preoperative clinical findings.
In some cases, an anterior chamber intraocular lens may be selected at the time of surgery if there is insufficient support for the back capsule. This type of lens can also be used after cataract surgery on only one eye as it provides minimal augmentation. Months or years after cataract surgery, the posterior capsule (behind the intraocular lens) may become cloudy. If this happens, the surgeon will perform a simple laser procedure to make an opening in it and restore clear vision.
Patients may also choose to wear sunglasses for greater comfort after cataract surgery as IOLs do not have a dark color. Children are even given artificial lenses after congenital cataract surgery because they will last a lifetime. An eye that has undergone cataract surgery without implanting an intraocular lens is called aphachic (phachic is the Greek root that denotes the lens). Other patients may not have received an intraocular lens at the time of their original cataract surgery, many years ago.
Because there is no unwanted augmentation, intraocular lenses provide the most natural vision after cataract surgery. Therefore, patients will choose from the same options available to all other people over 50 without cataracts or implants. While healthy eyes can be focused at any distance with the help of appropriate eyeglasses, there will be a certain distance at which the eye will focus naturally without glasses after cataract surgery.