All About Cataracts

The U.S. Food and Drug Administration (FDA) recently approved a new astigmatism-correcting intraocular lens (IOL) for use in cataract surgery. The new lens, called the AcrySof IQ Toric IOL, is manufactured by Alcon and is now available for use by cataract surgeons in the United States.

In addition to having a toric design to correct astigmatism, the new premium IOL also has aspheric curves to reduce a common post-surgical optical error called spherical aberration. By reducing spherical aberration, the AcrySof IQ Toric IOL is designed to improve image quality and contrast sensitivity for better night driving vision and sharper vision overall.

In a clinical trial required by the FDA prior to approval, among 37 patients who had the IOL implanted bilaterally for the treatment of cataracts and astigmatism, 98 percent did not need prescription eyeglasses for distance vision six months after surgery. Also, the lens continued to show good rotational stability when checked one year after surgery. 

According to Alcon, the AcrySof IQ Toric IOL is a good choice for any patient undergoing cataract surgery who has 0.75 diopter (D) or more corneal astigmatism prior to surgery. The IOL corrects up to 2.50 D of astigmatism, and it can be combined with a procedure called limbal relaxing incisions to correct even higher amounts of astigmatism.

Like other premium IOLs, the AcrySof IQ Toric IOL costs more than a conventional monofocal intraocular lens and will increase your cataract surgery cost. For details, consult a cataract surgeon near you.

The connection between nutrition and eye health is receiving plenty of study these days, as researchers are looking for ways people can lower their risk of age-related vision loss with eye vitamins or other nutritional means.

A new study published in the February 2009 issue of Current Eye Research suggests vitamin C may be a key to lowering the risk of the most common type of cataracts.

Researchers in Iran compared blood plasma levels of ascorbic acid (vitamin C) in age- and sex-matched populations of people with age-related cataracts and those without cataracts. Analysis of the data revealed that plasma levels of vitamin C among the subjects with cataracts were significantly lower than plasma levels of the antioxidant vitamin among those without cataracts.

The study also found that plasma levels of ascorbic acid declined with age among men, but not among women. Also, plasma levels of vitamin C were higher among people living in rural settings versus in cities, and women tended to have higher levels of this antioxidant vitamin in their blood than men did.

The researchers concluded that antioxidant vitamins, particularly vitamin C, “can help with the prevention of cataracts, which is a major health service burden in many countries.”

Vitamin C and other antioxidant vitamins are found in many fruits and vegetables, as well as in most vision supplements.

AllAboutVision.com (AAV) announced this month the launch of its new Cataract Surgeon Directory.

The directory will allow AAV visitors to find an experienced cataract surgeon in their area and schedule a consultation to learn more about cataracts, cataract surgery and the latest premium IOLs (intraocular lens implants) used to correct vision in modern cataract surgery.

The new cataract surgeon directory lists prominent eye surgeons located in cities and major metropolitan areas throughout the United States and Canada, and includes detailed information about each doctor, directions to their practice, contact information and a link to their websites.

AllAboutVision.com’s cataract surgeon directory is free and no registration is required.

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AllAboutVision.com was established in January 2000 and provides consumers independent, trustworthy information about eye health, eyecare and vision correction options. All health-related articles appearing at AllAboutVision.com are developed with input from AAV’s Advisory Board of prominent eye doctors. In 2008, more than 7.8 million unique visitors accessed AllAboutVision.com for information about eye care and eyewear, including contact lenses and vision surgery.

Advances in cataract surgery are occurring every year, making the procedure safer and more effective than ever.

A number of the key advances in cataract surgery took place in 2008. Among the new technology and techniques:

New Phacoemulsification Technology

Phacoemulsification (or “phaco”) is a cataract surgery technique in which the cataract is broken up into small pieces with a small, hand-held probe that has a vibrating tip. The small pieces are then removed from the eye with suction. Phaco is currently the most common technique used for cataract surgery in the United States.

Manufacturers of phaco equipment for cataract surgery introduced several advances in 2008, including probes that allow the procedure to be performed with smaller incisions. This reduces the risk of unwanted astigmatism after cataract surgery. Other advances include new microsurgical tools to help break up very dense cataracts more effectively during phaco cataract surgery.

New Lens Implants

New intraocular lenses (IOLs) introduced or in development in 2008 include presbyopia-correcting IOLs, aspheric IOLs and toric IOLs.

Presbyopia-correcting IOLs

These innovative lenses help restore a person’s ability to see well up close as well as far away, thereby reducing the need for reading glasses and computer glasses after cataract surgery.

The Crystalens HD (Bausch & Lomb) presbyopia-correcting lens that was introduced in 2008 works by having the ability to change position slightly within the eye in response to focusing effort. This type of presbyopia-correcting IOL is also called an “accommodating” IOL. Other brands of accommodating IOLs are currently in development.

Another type of presbyopia-correcting intraocular lens is the multifocal IOL. Multifocal IOLs are similar in design to multifocal contact lenses, containing separate lens powers for seeing distant, intermediate and near objects simultaneously. Examples of multifocal IOLs include The AcrySof ReSTOR IOL (Alcon Laboratories) and the ReZoom Multifocal Lens (Advanced Medical Optics).

Accommodating and multifocal IOLs can be implanted in both eyes, or in one eye only for a “monovision” effect. Some surgeons feel a monovision correction provides better distance vision than having presbyopia-correcting IOLs implanted in both eyes.

Aspheric IOLs

Aspheric IOLs are specially designed to more closely mimic the shape of the eye’s natural lens, which changes in curvature from its center to its periphery. This characteristic of possessing a gradually changing curve is called asphericity (meaning “not spherical,” or “not of the same curve”).

Because they are more similar in shape to the eye’s natural lens, aspheric IOLs are designed to provide sharper vision and reduce higher-order aberrations (HOAs) caused by traditional spherical IOLs. HOAs contribute to glare and reduced contrast sensitivity, especially at night and in other low-light conditions.

Many cataract surgeons appear to believe in the benefits of aspheric IOLs, as the use of thes premium IOLs grew rapidly in 2008.

Examples of aspheric IOLs include the Tecnis IOL (Advanced Medical Optics) and the AcrySof IQ IOL (Alcon Laboratories).

Toric IOLs

Toric IOLs are a new type of premium intraocular lenses that correct astigmatism.

In the past, people who had astigmatism and cataracts had to wear eyeglasses or have an additional surgical procedure to correct their astigmatism after cataract surgery. With toric IOLs, many of these people can see clearly after cataract surgery without the need for full-time glasses or additional surgery.

Use of toric IOLs increased significantly in 2008 and continued future growth is expected. Examples of toric IOLs include the AcrySof Toric IOL (Alcon Laboratories) and the STAAR Toric IOL (STAAR Surgical Co.)

More Advances on the Horizon

As the aging of the U.S. population continues, more and more Americans are having cataract surgery. And more advances in cataract surgery technology are occurring every year, including techniques for smaller incisions and faster recovery time.

To stay up-to-date on the latest news about cataracts and cataract surgery, return to AllAboutCataracts.com often. Or browse AllAboutVision.com’s Cataract Surgeon Directory to find a cataract surgeon near you.