The most effective and common treatment for treating cataracts is to
surgically remove the clouded natural lens and replace it with an intraocular
lens (IOL). This procedure restores the eye’s ability to pass light rays to the
retina for a focused image. Over 14 million IOL procedures are performed
worldwide each year. In fact, cataract surgery is the most common surgical
procedure in the world.
The cataract is removed through a process called phacoemulsification in which the cataract is broken up using ultrasonic waves. An intraocular lens implant is then placed in the eye. This procedure usually takes only 15 to 30 minutes.
Several types of intraocular lenses (IOLs) are available for lens replacement during cataract surgery. The IOL solutions offered at Sharper Vision Centers are listed below. Decisions about which procedure is best for you should be made in consultation with Dr. Oyakawa. The right solution for you will depend on your eye health, lifestyle, and personal preferences.
Aspheric IOLs
Aspheric IOLs are designed to restore the balance between two important components of vision, the cornea and lens. All modern camera lenses are aspheric. The goal is visual clarity and sharpness similar to what most people enjoyed in their twenties.
While providing safer, sharper distance vision, most aspheric IOLs do not eliminate the need for reading glasses. Some aspheric IOLs have been proven to improve contrast sensitivity and night-driving performance compared to conventional spherical IOLs. One option is to choose an aspheric lens that offers the best night-time driving vision, and to continue wearing glasses for close-up tasks.
AcrySof® IQ IOL corrects both cataracts and spherical aberration and is designed to provide improved image quality with high contrast. Learn more about Acrysof® IQ IOLs.
TECNIS® Monofocal IOL is specially designed for safety and sharper vision in low-light situations, such as night driving. Because the lens is monofocal (usually correcting distance vision only), patients may still require glasses for near tasks. Depending on individual eye health and lifestyle, this type of IOL may be a good choice.
Presbyopia-correcting options
If you have trouble reading up close, you may have presbyopia. Since most people with cataracts also have presbyopia, the good news is that both conditions can often be treated at the same time.
These lenses uses 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.
CrystalensHD™ 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 CrystalensHD™ 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 muscle function to achieve enough accommodation to perform near task and 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 close-up 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.
Several types of IOLs are available for correcting presbyopia. The presbyopia-correcting solutions offered at Sharper Vision Centers are listed below. 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.
Advantages of conventional IOLs
• Cost effective treatment for previous successful monovision patients • Decrease or eliminate 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
Presbyopia-correcting IOLs
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.
Array® Multifocal Implant provides correction for near, intermediate, and distance vision in a single lens. Currently used as a piggyback IOL implant in an eye with a conventional IOL and in low powers. Learn more about Array® Multifocal Implants.
Advantages of ReZoom™ IOL
• Offers better depth perception than monovision • Decreases or eliminates the use of glasses
Disadvantages of ReZoom™ IOL
• 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.
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
• 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 due to a large pupil
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.
Astigmatism correction
Many people receiving cataract 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.
AcrySof® Toric IOL can correct both cataracts and astigmatism simultaneously. However, they do not correct for presbyopia. Learn more about AcrySof® Toric IOLs.
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
