CONTACT LENSES TODAY

November 17, 2002

Contact Lenses Today® is edited by Dr. Joseph T. Barr and the staff of Contact Lens Spectrum. This week CLToday® reaches 9,056 readers in 74 countries.

Iris Scanning Sees Through CLs
The New York Times recently reported on the technology of iris scanning, which is currently used at two American airports to test employee security systems. When it comes to identifying and recognizing a person, the iris has more than 260 rings, furrows and freckles and other marks, which pales in comparison to the 30 to 40 unique characteristics of fingerprints or the 80 facial characteristics. But unlike in the movies, where someone can slip contact lenses over their eyes to mimic a cleared person's iris, these systems can accurately read your eyes even if you're wearing contact lenses or eyeglasses.

OptiStock Adds CL Edition to Financial Report
OptiStock MarketWatch, a series of sector-specific electronic reports produced for the investment community, has just released a new contact lens edition. The Contact Lens Edition includes commentary by analysts at Midwest Research and Robert Baird & Co. and contains information on company profiles, litigation and regulatory actions, the contact lens share of the vision correction market, other developments impacting public contact lens companies and more. To learn more visit http://www.optistock.com/mw/2002_11all.htm

The Beauty and Technology in Biomedics Colors -- The clinically proven Biomedics 55 design is now available in four popular colors -- blue, green, gray and hazel. Biomedics Colors offer your patients the most natural eye color without sacrificing comfort, vision or fit. Biomedics Colors are only sold to eyecare professionals. Call your Ocular Sciences account manager to get started today (877) 926-2800. For more information, visit http://www.ocularsciences.com/Sight/static/main.jsp
--ADVERTISING

New CLs Give Eyes a Twinkle
CIBA Vision recently launched GlitterEyes specialty contact lenses in the United States and in Canada. The lenses are available in three different colors: Crystal Blue, Orchid Ice and Beach Bronze. GlitterEyes lenses are available from plano to -6.00D in steps of 0.25D with a base curve of 8.6 mm and a diameter of 13.8 mm. They are manufactured to provide comfort and ease of handling for wearers by encapsulating the glitter within the lens so that it never touches the eye.

Myopia More Common in Ethnic Chinese Children
A recent study headed by Associate Professor Dr. Carly Lam at the Hong Kong Polytechnic University's Centre for Myopia Research concluded that ethnic Chinese children are more prone to myopia than are children of other ethnic groups. The researchers conducted a large-scale study on 1,078 school students aged 13 to 15 from three local schools and six international schools. According to the survey results, 85 to 88 out of every 100 students at Hong Kong schools were myopic, compared to 60 to 66 out of 100 at international schools. Even at international schools, researchers found that myopia was most common among ethnic Chinese children, with a prevalence rate of 80 percent.

Abstract: Comparing Back Surface Options to Enhance GP Lens Performance
Researchers at the Ohio State University compared the performance of four aspheric back surface GP designs to a spherical optic zone and peripheral curve back surface reference design. They measured oxygen uptake rates for each of 40 wearing combinations (five lens designs fitted to each of eight eyes) under blink and nonblink conditions for their effectiveness in reducing post-lens hypoxia. The researchers found that tear pump efficiency for each of the eight eyes (averaged responses across all five lens designs) ranged from a high of +12.3 exchange efficiency (EE) units down to -9.8 EE units (i.e., worse than non-blink condition of 0 EE units). Aspheric lens back surface and/or peripheral curve designs were found to vary significantly in their post-lens exchange efficiency performances, but no "universal problem solver" design was found among the five investigated, the researchers concluded.
Fink, BA; Mitchell, GL; Raasch, TW; Hill, RM. Enhancing RGP contact lens performance: Comparing back surface options. Optometry 73:605-613. (2002)

Editor's Commentary: Comment on the Etiology of Hyperopic Creep
When myopes get more myopic wearing contact lenses, some practitioners call it myopic creep. (A phenomena, not an insult!) Last week, our tip by Michael Feldman, O.D., discussed that some silicone hydrogel patients wearing plus lenses revealed more plus refraction with time after switching from low Dk/t lenses. Helen R. Wilson, O.D., suggests that this is from edema being resolved or from a possible Ortho-K-like effect from a higher modulus lens. My comment is: Both mechanisms are being investigated and we hope to have some answers soon.

Fitting Tip: Fuss with GPs
Do practitioners not fit GP lenses because of the fuss or because they weren't taught in school? Do they know that they can command higher fees and that GP patients are more loyal? Do they realize that GP progressives work well and that soft progressives rarely work? I just fit a -10.00 -6.00 x 32 in GPs and she's doing well. She's never been successful in soft torics. The tip is: Use GP lenses -- they work.
-- Robert D. Bard, Dallas

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