Around the age of 40–45 we all begin to lose the ability to see up close without the use of reading glasses or bifocal lenses; this condition is known as presbyopia. Presbyopia IOLs (Intraocular Lenses) are designed to provide a full range of vision without the use of bifocal or trifocal lenses.
The success of the operation depends heavily on the optical characteristics of the specific PCIOL (Presbyopia-Correcting Intraocular Lens), and on the specifics of the patient’s case, such as existing astigmatism, pupil size, and how well the eye heals. Traditional monofocal IOLs have been used to correct presbyopia conditions, but in recent times multifocal and accommodating lenses have become more popular.
Types of Presbyopia IOLs
The three available presbyopia-correcting IOLs are:
- The apodized diffractive AcrySof ReSTOR (Alcon): This is a diffractive technology, a design that responds to the width of the eye’s pupil in order to improve near, intermediate, and distance vision. This lens is said to improve contrast sensitivity and provide better night time vision than other types of multifocal IOLs. Studies show that 80 percent of people who’ve received this lens have had no need for eye glasses or contact lenses for any activities.
- The zonal refractive ReZoom (Advanced Medical Optics) is a multifocal refractive IOL that distributes light over 5 optical zones to provide near, intermediate and distance vision. Studies show that 93 percent of people reported never or only occasionally needing glasses.
- The accommodative Crystalens: was designed to restore the eye’s accommodation ability, which is reduced as presbyopia progresses. In FDA studies, about 80 percent of people who received the Crystalens HD could see at the near-vision equivalent of 20/20 after four months. It also hinges on both sides of the IOL, and it can be moved more easily by the ciliary muscle. This allows the eye to focus more naturally at a greater range of distances. So far, Crystalens HD is the only accommodating IOL that has been approved by the FDA.
Refractive Lens Exchange
One option for presbyopia correction involves removing the eye’s natural lens and inserting an artificial lens in its place through a procedure identical to cataract surgery. This procedure is called Refractive Lens Exchange (RLE). This surgical procedure, also known as Clear Lens Extraction, is not FDA-approved specifically for presbyopia correction, but it is available “off label” for qualified candidates. The procedure is becoming more popular because of the recent availability of the three FDA-approved multifocal or accommodative artificial lenses capable of correcting presbyopia.
Mixing Multifocal Cataract Lenses
There is a new “fix” on its way into the mainstream called “mixing.” Some doctors have suggested that the best way to meet patients’ expectations is by “mixing” presbyopia-correcting IOLs. To date, not much evidence has been presented to support this approach.
Furthermore, many surgeons who’ve tried mixing lens technologies are returning to bilateral implantation. Most doctors say that when performing presbyopia-correcting surgery, the same technology should be used in both eyes. This method has yet to be approved by the FDA.
Benefits of IOLs for Presbyopia
Multifocal and accommodating lenses are better than traditional monofocal lenses because they improve vision at near, far, and in-between distances all at once. Another benefit to these lenses is that they eliminate the need for eyeglasses in most people. Unless your individual case needs more attention, PCIOLs will give you perfect vision once again.
Drawbacks of IOLs for Presbyopia
As with any surgical procedure, there are benefits and drawbacks. Here are a few things you should be aware of:
- Enhancements: In almost 15 percent of surgeries preformed by experienced cataract surgeons, it is necessary to go back to perform enhancements.
- Extra Surgery: You may need additional surgical procedures like LASIK, or the insertion of an additional IOL (piggy-back lens) to perfect your uncorrected vision. Unfortunately, because presbyopia IOLs are relatively new, most cataract surgeons are not experienced enough to perform this surgery. It’s crucial you find a surgeon with this experience. If you have lingering astigmatism, a procedure known as “limbal relaxing incisions” may also be necessary to flatten your eye’s surface. Also, some multifocal lenses may cause disturbances to your vision such as glare and halos around light at night.
- Costs: Another drawback to implanting PCIOLs is that they are more expensive. It costs manufacturers more money to produce them, and it requires a more experienced surgeon to perform the surgery. Plus, most insurance companies see multifocal and accommodating lenses as elective, and only cover the cost of the basic intraocular lens and the cataract surgery.
Talking to Your Eye Doctor
Here are some questions to ask your eye doctor about presbyopia IOLs:
- Would I benefit from presbyopia IOLs?
- Which one would benefit me most?
- What are the costs associated with these types of IOLs?
- Does my insurance cover the costs of this procedure?
- What are my other options?
- What are the chances I will need to have a second surgery?
- Would I benefit more from refractive lens exchange?