Choosing the best surgical treatment option for presbyopia is very important.
Many patients who need surgery for presbyopia will also develop cataracts
in the next 10 years. While vision can temporarily be improved with glasses,
eventually cataract surgery is required to restore vision.
Surgery for presbyopia involves removing the inflexible natural lens from the eye and replacing it with a new lens that will help you to focus better. These lens are called intraocular lenses, or IOLs.
Several types of procedures and IOLs are available. Decisions about which procedure is best for you should be made in consultation with Dr. Oyakawa. The right presbyopia solution for you will depend on your eye health, lifestyle, and personal preferences.
Presbyopia-correcting intraocular lenses (PC-IOLs) provide clear vision at most distances. During an elective procedure known as refractive lens exchange (RLE), the eye’s natural lens is replaced with one of these artificial lenses. Other patients need to focus at a wider range of distances because of their profession, sports activities, or personal preferences. An added benefit is not needing cataract surgery in the future.
Accommodative IOLs
These lenses use the muscles of the eye to change the shape of the IOL, similar to a slightly presbyopic eye. Unlike multifocal IOLs, they do not split light between various focal points to achieve presbyopia correction.
CystalensHD™ IOL is designed to move forward and backward, like the natural lens of a young, healthy eye. Dr. Oyakawa received the Crystalens Center of Excellence award in January 2008.
Learn
more about CrystalensHD™ IOLs.
This demonstrates the movement of the Crystalens IOL as it focus from distant to near objects.
Rollover image to view
Advantages of CrystalensHD™
Higher quality of vision compared to multifocal IOLs because light is not split between different focal points.
Excellent distant and intermediate vision
Excellent for patients who do a lot of work on computers
Disadvantages of CrystalensHD™
Some patients may not recover enough muscle function for good near vision, and may need to use simple readers.
Conventional Spherical Monofocal IOLs
Monovision is a strategy in which vision is optimized for one particular distance. Conventional (spherical monofocal) IOLs have been used to treat cataracts for over 30 years. Replacing the cataract with a conventional lens implant greatly improves vision at a single focal point, usually distance, but generally requires the use of reading glasses or bifocals for near and intermediate range vision. In some cases, the eyes are implanted with different lenses, one for near vision and one for far.
Patients who undergo cataract surgery with standard IOLs experience presbyopia. Standard IOLs are monofocal lenses that cannot focus both for distance and near. They also do not correct astigmatism and if left uncorrected vision will be reduced. Glasses will correct for the astigmatism and presbyopia.
Advantages of conventional IOLs
Cost-effective treatment for previous successful monovision patients
Decreases or eliminates the use of glasses
Disadvantages of conventional IOLs
Binocularity (use of both eyes) is reduced for viewing objects
Decrease in depth of field (ability to judge distance)
A compromise between good depth of field and decrease in use of glasses
Multifocal Refractive IOLs
These lenses have rings of different optical powers, similar to trifocal or progressive glasses, which bring distant, intermediate, and near objects into focus at the same time.
ReZoom™ Multifocal IOL provides a full range of vision so you can see objects at near, intermediate, and far distances. Learn more about ReZoom™ Multifocal IOLs.
Splits light into multiple images, reducing the quality of vision
More halos and glare compared to monofocal IOLs, although most patients adapt. A few patients do not adapt and have difficulty driving at night.
Near vision is dependent on the pupil dilating, and in bright sunlight, near vision is reduced. Some patients are not candidates for this lens because their pupils are too small.
Multifocal Diffractive IOLs
These lenses have rings of different optical powers, similar to bifocal glasses, which brings distant and near objects into focus at the same time. The brain chooses the correct image to see. The center part is for near and the outer parts are for distance. It may take some time for the brain to adapt.
The AcrySof® ReSTOR® Aspheric IOL is designed to provide quality vision throughout the entire visual spectrum—near through distance—with increased independence from reading glasses or bifocals. Learn more about AcrySof® ReSTOR® Aspheric IOLs.
Advantages of AcrySof® ReSTOR® Aspheric IOL
Offers better depth perception than monovision
Excellent near vision
Decreases or eliminates the use of glasses
Disadvantages of AcrySof® ReSTOR® Aspheric IOL
These lenses splits light into multiple images, reducing the quality of vision
More halos and glare compared to monofocal IOLs, although most patients adapt. A few patients do not adapt and have difficulty driving at night.
Due to the bifocal design, intermediate vision (computer, cooking, etc.) is not as good.
Near vision is dependent on the pupil size, and in dim light, such as a restaurant, near vision is reduced. Some patients are not candidates for this lens because their pupils are too large.
Light Rays
A monofocal IOL, such as the Crystalens, focuses light to a single point.
A diffractive multifocal IOL, such as the Restor®, splits light into two main images.
A refractive multifocal IOL, such as the ReZoom™ IOL, splits light into two main images.
Dr. Oyakawa started presbyopia-correcting cataract surgery in 2000 and has implanted all FDA-approved presbyopia-correcting IOLs. Only a minority of cataract surgeons are implantating presbyopia-correcting IOLs, and most of them did not start until after 2006.
LASIK vision correction of presbyopia
One of the first effective surgical options for presbyopia correction involved achieving what is known as "Monovision" during LASIK. The refractive error is corrected in the dominant eye and the other eye is set to see near. This can also be done in a patient who can see distance well in both eyes. One eye can be made nearsighted with the excimer laser or CK. CK can only correct hyperopia to make an eye slightly myopic.
Dr. Oyakawa recommends Monovision LASIK only for myopic eyes with no signs of cataracts. Dr. Oyakawa himself has had Monovision PRK and occasionally uses glasses for prolonged reading and when repairing computers or other mechanical devices when added depth perception is needed. At surgery and during slit lamp examination, the surgical microscope and slit lamp is adjusted to compensate for his Monovision to give normal depth perception. He does not recommend it for hyperopic eyes.
What you can expect with Monovision LASIK
Successful Monovision adaptation occurs in 3 to 4 weeks in about 80% of patients
Main advantage is not needing reading glasses for seeing near
Disadvantage is some decrease in depth perception
Patients in their 40s usually adapt to Monovision in 1 to 2 weeks, while older patients may take a few months
Patients who do not have significant astigmatism can try contact lenses before Monovision LASIK
A few patient may need to use glasses for night driving or prolonged computer work and reading
Some patients use one disposable contact lens in their near eye for good binocular vision during sports, such as tennis
In rare situations, some patients decide later to have the eye with near vision corrected to allow distance vision
Other option for presbyopia correction:
Conductive keratoplasty (CK) uses low-level, controlled radio frequency energy to shrink collagen on the edges of the cornea to give it a better shape. Learn more about conductive keratoplasty (CK).
Astigmatism correction
Many people receiving presbyopia surgery also have a condition called astigmatism. If you have astigmatism, your cornea is irregularly shaped. Instead of being shaped like a basketball, it is shaped like a football. Astigmatism causes rays of light entering though different parts of the eye to focus unequally so that they never form a single focus. As a result, things look blurry because images are not focused clearly on the retina. Untreated, astigmatism requires glasses or special contacts.
Fortunately, Dr. Oyakawa offers other options for correcting astigmatism.
Laser is used for moderate degrees of astigmatism. Lasers are approved by the FDA for specific levels of astigmatic correction. We have a laser specification table that can show you exactly what degree of astigmatic correction, if any, a laser is approved to perform.
