Intraocular Lenses (IOLs)
As you have seen on previous pages, when your native lens becomes cloudy you have a cataract. When cataract surgery removes this cloudy lens, a new crystal-clear intraocular lens is almost always placed in order to refocus images.
Before discussing these replacement IOLs, you must learn about something called presbyopia. Presbyopia is a natural age-related part of life, and usually starts to affect people at about age 40-50. It results from the lens slowly losing its elasticity as the lens thickens over the years. When we are younger, we have a muscle inside of our eye that contracts when we attempt to focus on a close object like a book. After the muscle contracts, the lens “fattens” and increases its refractive power, which allows us to see the near object clearly. With the decrease in lens elasticity that occurs with increasing age, the eye has a hard time focusing on near objects. This is why you see people wearing reading glasses or “cheaters” while reading restaurant menus, threading a needle, or tying a fishing lure - they are suffering from presbyopia.
Before your cataract procedure, you can choose between a standard lens implant and a premium lens implant. A standard lens implant can provide you with excellent distance vision, but you will still need glasses for near vision. The standard lens implant does not combat presbyopia. A premium lens implant attempts to provide clear vision at multiple distances, such as far and near.
Standard IOLs have been used for over 30 years in cataract surgery. They can provide excellent distance vision (such as seeing street signs or watching a golf ball) for patients. You will still need glasses to help get intermediate (such as a computer screen) and near (such as reading the newspaper) objects in focus.
Premium IOLs have been used for approximately 15 years. There have been several different designs over the years. The newest generation of premium IOLs have had excellent results, and their popularity is exploding. Another name for these lenses could be “presbyopia-correcting” IOLs because the goal is to give you more than just good distance vision. In addition to giving you good distance vision, some of these IOLs will give you great near vision as well, while others will give you great intermediate vision as well. Their goal is to reduce your dependency on reading glasses or bifocals – can you imagine being glasses free?
The Restor IOL is a multifocal IOL – it incorporates both distance and near powered lenses into one IOL. The lower power zones bend light coming from distant objects to a clear focus on the retina. The higher power zones bend light from near objects to the same clear focus on the retina. Thus, different zones of lens power work together to provide the eye with near and distant vision! This lens is usually implanted into both eyes after cataract surgery. Between 85-90% of patients do not wear glasses (for any distance) after the surgery!
Tecnis Multifocal IOL
The Tecnis Multifocal IOL is similar to the Restor IOL in design in that there are both distance and near powered lenses incorporated into a single IOL design. There are minor differences that Dr. Rhodes will discuss with you based on your individual vision needs. Just like the Restor IOL, 85-90% of patients do not wear glasses after having this lens implanted into both eyes!
The Crystalens combats presbyopia with a completely different design than the multifocal IOLs. This lens attempts to use the eye muscle we previously discussed, and actually move forwards and backwards naturally in response to the brain’s desire to see at different distances. As the IOL moves, objects at different distances come into focus! This allows for continuous vision at both far and near.
If you are interested in premium IOLs, please notify Dr. Rhodes, and he will be happy to discuss your options with you during your clinic visit.