All About Cataracts

A multifocal IOL recently approved for use in the United States produces a wide range of clear vision and a high degree of independence from eyeglasses after cataract surgery, according to a multi-center European study published this month in Journal of Cataract and Refractive Surgery.

The study evaluated the performance of the AcrySof IQ ReSTOR IOL with +3.0 D add power implanted in both eyes of 93 patients. The procedures took place at five European sites and were performed by five surgeons.

At 6 months after surgery, mean binocular uncorrected visual acuity was better than 20/20 at distance (4 meters), approximate 20/30 at arm’s length and slightly better than 20/20 vision at the patient-preferred reading distance (approximately 16 inches).

In a postoperative survey, the mean patient satisfaction with their vision was 8.3 out of 10, and 88 percent of the patients did not need eyeglasses after surgery.

Results of a new study show that implantation of a light-filtering intraocular lens (IOL) during cataract surgery increases the amount of important nutrients in the eye and may reduce the risk of age-related macular degeneration.

The special IOL blocks high energy visible light (also called HEV light or blue light) that has been associated with damage to the retina. This damage occurs in the most sensitive part of the retina called the macula, which is responsible for central vision and color vision.

Prolonged exposure to blue light depletes macular pigments that protect important visual cells in the retina called photoreceptors. The blue light-filtering IOL helps preserve or increase these pigments, thereby reducing the risk of macular degeneration, according to the researchers.

Macular pigments include lutein and zeaxanthin.

In the study, 42 patients scheduled for cataract surgery were randomly assigned to have either the blue light-filtering acrylic IOL or a standard acrylic IOL implanted during their procedure.

Macular pigment optical density and blood serum levels of lutein and zeaxanthin were measured prior to surgery and at one week and three, six and 12 months after surgery.

The researchers found that there was an increase in protective macular pigments over time (as measured by optical density) in eyes with the light-filtering IOL implant, but no such increase in eyes with the standard IOL.

They concluded that this suggests the light-filtering IOL may reduce the risk of macular degeneration after cataract surgery, but they cautioned that further and long-term study is needed to determine if this is true.

Macular pigments are obtained entirely from the diet and are transported to the retina through the blood. Because of growing evidence that macular pigments play a role in reducing the risk or progression of macular degeneration, many commercially-available eye vitamins contain lutein and zeaxanthin.

A full report of the study appears in the October issue of Investigative Ophthalmology & Visual Science, the journal of The Association for Research in Vision and Ophthalmology (ARVO).

The use of premium intraocular lenses (IOLs) in cataract surgery performed in the United States is increasing, according to recent surveys.

Premium IOLs include multifocal lens implants and accommodating IOLs. Both types of presbyopia-correcting intraocular lenses give patients a broader range of vision, reducing or eliminating the need for reading glasses after cataract surgery.

According to a recent survey of cataract and refractive surgeons reported by the eyecare industry research firm Market Scope, 71 percent of U.S. eye surgeons offered their patients the option of premium IOLs in 2008, up from approximately 59 percent in 2007. The company also estimates that 210,000 presbyopia-correcting IOLs were implanted during cataract surgery or other vision correction procedures in the U.S. in 2008, up from 153,000 in 2007.

Eye surgeons also say they prefer premium IOLs for the correction of high myopia. In a 2008 member survey of the American Society of Cataract and Refractive Surgery (ASCRS) more eye surgeons responding to the survey reported preferring premium IOLs (40 percent) to LASIK (23 percent) for the correction of large amounts of nearsightedness in patients desiring elective refractive surgery.

Among ASCRS surgeons using presbyopia-correcting premium IOLs, their top three lens choices in 2008 were the AcrySof ReSTOR multifocal IOL (Alcon), the Crystalens accommodating IOL (Bausch & Lomb) and the ReZoom Multifocal IOL (Abbott Medical Optics).

Other premium intraocular lenses include toric IOLs that correct astigmatism and aspheric IOLs designed to reduce glare and improve night vision.

Premium IOLs cost more than standard IOLs, and the added expense of these lenses typically is not covered by vision insurance and must be paid out-of-pocket, increasing your cataract surgery cost. However, most people who choose premium IOLs are very pleased with the added visual benefits the lenses provide, according to eye surgeons who offer them.

Most people undergoing cataract surgery with implantation of a multifocal intraocular lens (IOL) require approximately six months to fully adapt to the IOL and achieve maximum visual benefit, according to new research from Spain.

Researchers at Hospital Quiron in Madrid evaluated the visual performance of patients receiving the Tecnis Multifocal IOL (Abbott Medical Optics, Santa Ana, Calif.) over time after their cataract surgery. A total of 250 eyes of 137 patients received the multifocal IOL, and patients were evaluated at intervals of one to three days, 30 to 90 days and 150 to 210 days after surgery.

Results of the study revealed that the patients demonstrated a significant improvement in uncorrected and spectacle-corrected visual acuity at both distance and near over the course of the seven-month study period.

At the last follow-up visit (roughly six months after surgery), eye chart testing of the visual acuity (VA) of eyes receiving the multifocal IOL revealed:

• 77.6 percent had uncorrected distance VA of 20/30 or better.
• 98.4 percent had best spectacle-corrected distance VA of 20/30 or better.
• 96.8 percent had uncorrected near VA of 20/25 or better.

More than 90 percent of the patients rated their near, distance and overall vision as good or excellent, and 88.4 percent of the patients did not wear eyeglasses or reading glasses.

Over the course of the study, most patients experienced an improvement in their visual acuity at all distances and a decrease in the intensity of glare and other undesired visual phenomena.

The researchers concluded that the Tecnis Multifocal IOL provides excellent uncorrected near vision and good distance vision when used to treat cataracts. Most patients, however, required an adaptation period of approximately six months to experience the full visual benefits of the lens, they said.

You can learn more about the Tecnis Multifocal IOL by visiting this Abbott Medical Optics website.