All About Cataracts

Researchers in Canada have found that expedited cataract surgery among older patients improves visual acuity but does not appear to significantly reduce the risk of falls among this population.

The investigators conducted a systematic review of several studies that evaluated the effect of surgical removal of cataracts shortly after they were discovered as a measure to improve vision and reduce the risk of injury among older adults. Both published and unpublished studies dating from 1950 to 2008 were included in the research.

Vision data from 737 patients were included in the analysis. Analysis of the data showed that expedited cataract surgery significantly improved visual acuity in most cases. But analysis of pooled data from 535 patients showed only a nonsignificant reduction of falls after cataract surgery.

The researchers concluded that accumulating evidence indicates expedited cataract surgery is effective in significantly enhancing vision but is inconclusive in preventing falls.

The full report of the research appears in this month’s issue of Journal of Cataract and Refractive Surgery.

The results of the study are contrary to research reported in the April 2007 issue of the Canadian Medical Association Journal (CMAJ),* which found evidence that vision and quality of life decrease, and the rate of falls increases, among patients during the waiting period for cataract surgery.

*The consequences of waiting for cataract surgery: a systematic review. CMAJ. Vol 176, No 9. April 24, 2007.

Bausch & Lomb today announced the worldwide launch of a new accommodating intraocular lens (IOL) with aspheric optics for use in cataract surgery.

The new IOL, called Crystalens AO, is designed to be free of spherical aberration that affects other IOLs and thereby produce sharper vision after cataract surgery. The announcement follows recent FDA approval of the Crystalens AO for use by cataract surgeons in the United States.

The aspheric optical surfaces of Crystalens AO are designed to improve retinal image quality without compromising depth of field, and therefore the new IOL provides higher quality distance and intermediate vision than other IOLs, according to the company.

“The Crystalens AO has zero spherical aberration, and the combination of the Crystalens platform and AO optics work together to enhance depth of field,” says Andy Corley, president of Bausch & Lomb’s global surgical division in a press release issued today by the company.

The Crystalens AO is the latest addition to the Crystalens line of accommodating IOLs produced by Bausch & Lomb, joining the Crystalens HD and the Crystalens Five-O. Currently, Crystalens is the only brand of accommodating IOL that is FDA-approved for use in cataract surgery performed in the United States.

Unlike conventional IOLs, the optical portion of accommodating IOLs can move slightly within the eye in response to focusing effort, to improve not only distance vision, but intermediate and near vision as well, reducing the need for reading glasses after cataract surgery.

Accommodating IOLs are a premium intraocular lens and therefore will increase your cataract surgery cost.

More information about Crystalens accommodating IOLs is available on Bausch & Lomb’s Crystalens website or by calling the company at 1-877-SEE BETTER.

In its December 15 issue, Ophthalmology Times published a “year in review” feature, highlighting key developments in cataract surgery that took place in 2009.

Advances in cataract surgery technology in 2009 included:

Approval of femtosecond laser technology for cataract surgery

In September, the LenSx laser (LenSx Lasers, Inc., Aliso Viejo, Calif.) became the first femtosecond laser to gain FDA approval for a specific step in the cataract surgery procedure, eliminating the need for a bladed instrument for this step. Proponents say femtosecond laser technology (currently used primarily for LASIK and other laser vision correction procedures) could make a cataract operation even more safe and effective, reducing the risk of certain cataract surgery complications.

New multifocal IOLs

Two new multifocal IOLs were introduced to the U.S. market in 2009: the Tecnis Multifocal IOL (Abbott Medical Optics, Santa Ana, Calif.) and the AcrySof IQ ReSTOR +3.0 D (Alcon Laboratories, Fort Worth, Texas). Both lenses are designed to help patients regain a fuller range of vision after cataract removal and reduce their need for reading glasses. According to preliminary studies, both lenses offer patients a higher degree of freedom from glasses than previous multifocal intraocular lenses.

Investigational IOLs

A number of companies were conducting clinical trials of new premium IOLs not yet approved for use in the United States. These include a “light-adjustable lens” (LAL) being developed by Calhoun Vision (Pasadena, Calif.). The power of this lens can be adjusted by exposing it to a specific wavelength of light 2 to 3 weeks after cataract surgery, depending on the patient’s visual needs.

Another premium IOL under study is an accommodating IOL called the NuLens (NuLens, Ltd., Herzeliya, Israel and Alicante, Spain). Preliminary studies suggest the NuLens can produce significantly greater near focusing power than currently available accommodating IOLs for even greater freedom from reading glasses after surgery.

SOURCE: 2009: A banner year in cataract surgery. Ophthalmology Times. December 15, 2009.

If you have cataracts and also are being treated for glaucoma, cataract surgery may reduce your need for glaucoma medications and surgery, according to a new study.

Researchers in Korea recently conducted a retrospective study of 96 people with glaucoma who underwent phacoemulsification cataract surgery with intraocular lens (IOL) implantation for the treatment of clinically significant cataracts. Forty-eight of the patients had primary open-angle glaucoma (POAG) and 48 had primary angle-closure glaucoma (PACG).

While previous studies have shown that cataract extraction with IOL implantation lowers intraocular pressure (IOP) in patients with and without glaucoma, the focus of this study was to determine which type of glaucoma patients are most likely to achieve the greatest IOP-lowering effect of cataract surgery.

The follow-up period ranged from 24 to 54 months, with a mean of 31 months.

The researchers found that cataract surgery successfully controlled the IOP of 39.6 percent of eyes with POAG and 62.5 percent of eyes with PACG. The criteria of success was attaining an IOP of 21 mm Hg or lower without medical glaucoma treatment or with fewer anti-glaucoma medications than before surgery.

Among eyes with primary open-angle glaucoma, pre-operative factors increasing the likelihood of successful IOP control after cataract surgery were a maximum IOP lower than 31 mm Hg and use of fewer than three anti-glaucoma medications.

Pre-operative factors increasing the likelihood of success among eyes with primary angle-closure glaucoma were a maximum IOP lower than 42 mm Hg, use of fewer than three anti-glaucoma medications and less than 30 percent of the drainage angle of the anterior chamber of the eye being affected by iris adhesions called peripheral anterior synechiae.

The researchers concluded that modern small-incision cataract surgery using phacoemulsification and foldable IOL implantation may help control IOP in some glaucoma patients, reducing or eliminating their need for anti-glaucoma medicine and/or glaucoma surgery.

The study was published in this month’s issue of Canadian Journal of Ophthalmology.