Cataract surgery is the removal of the natural lens of the eye (also called “crystalline lens”) that has developed an opacification, which is referred to as a cataract. Metabolic changes of the crystalline lens fibers over the time lead to the development of the cataract and loss of transparency, causing impairment or loss of vision. During cataract surgery, a patient’s cloudy natural lens is removed and replaced with a synthetic lens to restore the lens’s transparency.
Phacoemulsification (Phaco) is the preferred method in most cases. It involves the use of a machine with an ultrasonic handpiece equipped with a titanium or steel tip. The tip vibrates at ultrasonic frequency (40,000 Hz) and the lens material is emulsified. A second fine instrument (sometimes called a cracker or chopper) may be used from a side port to facilitate cracking or chopping of the nucleus into smaller pieces. Fragmentation into smaller pieces makes emulsification easier, as well as the aspiration of cortical material (soft part of the lens around the nucleus). After phacoemulsification of the lens nucleus and cortical material is completed, a dual irrigation-aspiration (I-A) probe or a bimanual I-A system is used to aspirate out the remaining peripheral cortical material.The most common replacement of cataractous lens is an IOL. Before having surgery, review with your doctor the advantages and disadvantages of each type of replacement lens. A variety of IOL types are available. Your doctor can help you choose the type that may work best for you.
An IOL is placed inside the eye during surgery. Corrective glasses may be needed after surgery for reading and close work. But they are not as thick and heavy as traditional cataract glasses.
When thinking about how an IOL will affect your vision following cataract surgery, some types of IOL to consider are:- Monofocal IOLs. This type of intraocular lens is designed for either near or distance vision. If you have this type of IOL implanted in your eye(s), you will probably need to also wear glasses. For example, it is common for the IOLs to be chosen to provide better distance vision than near vision. Then glasses are used for sharp near vision.
- Toric IOLs. This is a type of monofocal IOL that helps correct astigmatism. It may be considered a premium lens, so it might cost more than a monofocal IOL.
- Multifocal (or accommodative) IOLs. This type of intraocular lens design provides correction for both near and distance vision, and both near and far objects can be in focus at the same time. Your brain must learn to select the visual information it needs to form an image of either near or distant objects, so multifocal IOLs may require some adjustment. A person may adjust better to multifocal IOLs if they are placed in both eyes. This type of lens is not an option for some people. It may be considered a premium lens, so it might cost more than a monofocal IOL. Talk to your eye doctor about the pros and cons of each type of IOL.