CONTACT LENSES TODAY
October 15, 2006
Contact Lenses Today® is edited by Dr. Joseph T. Barr and the staff of Contact Lens Spectrum. This week CLToday® reaches more
than 12,000 readers in 74 countries.
LASIK Versus Contact Lenses
A letter in the Oct. 10th issue of Archives of Ophthalmology compares the risks of refractive surgery with those of contact lens wear. The authors
used previous studies to estimate the number of infection cases with each form of treatment. They estimate the lifetime risk of bacterial keratitis at one case per 100
for daily-wear contact lenses and the risk of vision loss to a visual acuity of 20/70 at one in 2,000. The risk of vision loss from
Acanthamoeba keratitis is estimated
at one case per 60,000 persons per year, or one in 2,000 in a lifetime. The risk of more than two lines of vision loss from refractive surgery was calculated to be about one
case per 10,000. The authors note that highly oxygen permeable contact lenses should lessen the risks for that modality, however, laser surgery will also become
safer. They conclude that data from large, peer-reviewed studies strongly suggest that our intuition regarding these risks need to be reassessed. Read the full text
at http://archopht.ama-assn.org/cgi/content/full/124/10/1510-a.
Blanchard Launches Rose K IC Lens
Blanchard Contact Lens Inc. introduces its Rose K IC contact lenses, designed
as large diameter, specialty GP lenses for irregular cornea
applications. The lenses are manufactured with a larger posterior optical zone than standard lenses, an aspheric posterior surface aberration control optic and reverse
geometry para-central fitting curves.
The Rose K IC comes in a standard diameter of 11.2mm, with availability up to 12.0mm. They are indicated
for all irregular cornea applications. Primary applications include pellucid marginal degeneration, globus cones, post graft and LASIK-induced ectasia with secondary
applications for nipple and oval cones.
NIH Seeks AMD Participants for AREDS2
The National Institutes of Health is seeking 4,000 study participants with AMD between the ages of 50 and 85 for AREDS2. The study will
build upon the results of the original AREDS study, which found high-dose antioxidant vitamins and minerals reduce the risk of progression to advanced AMD by 25%, and
will be conducted at nearly 100 clinical centers nationwide. AREDS2 will add Lutein, zeaxanthin and the omega-3 fatty acids DHA and EPA to the original study formulation
to determine if these nutrients will further decrease a person’s risk of progression to advanced AMD. For a list of study centers, eligibility requirements and other
information, visit http://www.nei.nih.gov/AREDS2 or call 1-877-AREDS-80.
Real-World Advantages
A traditional ballast lens design means more interaction between the contact lens and lid, causing less stability when the eye is open. The Accelerated
Stabilization Design (ASD) of ACUVUE® ADVANCE™ Brand Contact Lenses for ASTIGMATISM means less interaction between the lens and the lid. The design breakthrough
of the ACUVUE® ADVANCE™ Brand for ASTIGMATISM offers real-world results for your patients: crisp, stable vision throughout daily activities and superior
rotational stability. Patients reported very good or excellent vision during night driving, while playing or watching sports, or working on a computer. With
ACUVUE® ADVANCE™ for ASTIGMATISM, the difference is clear to your patients. And now, ACUVUE ADVANCE for ASTIGMATISM meets more patients' needs with the
introduction of -2.25 cylinder.
--ADVERTISING
Global Keratoconus Congress 2007
Register now for the first-ever Global Keratoconus Congress to be held January 26-28, 2007 in Las Vegas. This meeting will be hosted at Bally’s on the Las
Vegas Strip. Please visit http://www.gkc2007.com. There you will find the most up-to-date educational program agenda and information
on hotel accommodations, as well as the ability to register for the event.
--ADVERTISING
Lagado Applies for Patents
The Lagado Corporation has filed both U.S. and International patent applications for a series of novel super-permeable contact lenses to be
made from polyacetylenes. These polymers have oxygen permeability as high as 6,000 barrers (Dk). The new lenses will be surface treated by plasma polymerization to impart
wettability. The company plans to begin testing in 2007.
VSP Launches Marketing Campaign
Vision Service Plan (VSP) has launched a marketing campaign to increase awareness of the importance of regular eye exams. Blending
educational and interactive components, Windows to Your Memories will be e-mailed to nearly 35,000 consumers who requested eye health information from the company.
Patients can view the campaign and then forward it on to others. The Flash video is available
at http://www.vsp.com/email/window.html.
Prevent Blindness America Searches for Citizen Advocates
Prevent Blindness America is beginning the application process for the 2007 Eyes on Capitol Hill campaign. The second annual event is
designed to allow those affected by real-life vision issues an opportunity to discuss their experiences with their government representatives. It will begin on Feb.
28 in Washington D.C. with discussions on federal funding efforts for vision programs and research as well as seminars on how participants can become effective
advocates in their communities. Participants will meet with congressional members the following day.
An unrestricted grant from Pfizer will
allow Prevent Blindness America to offer an unlimited number of scholarships to some attendees, which will cover all travel and hotel expenses for each participant
and a companion or guardian if necessary. The deadline for application is Dec. 4, 2006 and all applicants will be notified of their status by Dec. 22.
Visit http://www.preventblindness.net/eyesoncapitolhill.
Contact Lens Institute Plans New Initiative
The Contact Lens Institute (CLI) canceled its Contact Lens and Eyecare Symposium (CLES)
several months ago and is now evaluating new initiatives, including the
potential repositioning of the Contact Lens Council as a marketing/educational tool for the industry. CLI members include Advanced
Medical Optics (AMO), Alcon, Bausch & Lomb (B&L), CIBA Vision, CooperVision and Vistakon.
Abstract:
New Method to Assess CL Oxygen Permeability
A recent study at the Central Leather Research Institute’s Bioproducts
Laboratory in India describes a new way to measure contact lens oxygen
permeability and transmissibility. Researchers are able to accurately measure
oxygen across the material by allowing oxygen to pass through the lens material
in a specially fabricated lens mould. They collected expelled oxygen by dissolution in ethanol and then measured it by titration of the
solvent.
The investigators found this method suitable for measuring oxygen permeability and transmissibility of contact lenses of varying
thicknesses and different radii of curvature. It was also able to measure Dk and Dk/t of collagen, bandage lenses in both wet and dry conditions. The study report
compares the values obtained by this method with standard values of commercially available contact lenses.
Hadassah J Sehgal P. A novel method to measure
oxygen permeability and transmissibility of contact lenses. Clin Exp Optom. 2006 Nov;89(6):374-80.
Editor's Commentary:
LASIK Safer than CLs?
In our first story, the information from the Archives of Ophthalmology piece by Bill Mathers, M.D., Frederick Fraunfelder, M.D. and
Larry Rich, M.D. is startling. I’ve discussed this with dozens of O.D.s these past few days and they just shake their heads. Seems like there's no argument that
contact lens wearers may have more infections of all sorts, and this is not acceptable and we need to continue to strive to eliminate these risks. But the contention
that there is more vision loss with contact lenses than with refractive surgery is perplexing and not what we see in practice. Maybe our colleagues in ophthalmology
see the patients with contact lens related vision loss and we see the patients with refractive surgery vision loss.
Patient selection is always
an issue in studies. Let me add to the exchange a bit. Some quotes from the highly-regarded authors of the aforementioned piece
include, "If one assumes," "estimated," "extrapolated," "was not specified," "calculated," "laser surgery will become safer," and "look forward to further investigations
of these risks." It seems much of what is concluded is based on conjecture. They also say, "the risks of refractive surgery vs. contact lenses cannot be compared
directly." Those of us who have tried to do so know this. So why do we keep trying? These are both very good treatments for refractive error and other
conditions.
Fitting Tip:
Toric Lens Tip
For your patients with irregular astigmatism, classic or globular keratoconus, who have been unsuccessful with GP, hybrid or
piggyback lenses, try the new PureVision Toric lens (B&L). It must be the lens modulus, but many of these patients achieve better visual acuity than you expect,
with great physiology and comfort. It’s a pragmatic fitting process, usually using less minus and cylindrical correction than you expect. It may also take a while
for the cornea to stabilize, especially when converting from rigid lenses. You can always correct residual astigmatism with spectacles when the prescription
stabilizes. Try them, you will be surprised and your patients will be delighted.
Patricia M. Keech, O.D., F.A.A.O.
Shoreline, Wash.
This month at http://www.siliconehydrogels.org, learn more about the new silicone hydrogel materials and develop an
understanding of piggyback lens systems.
Report adverse contact lens reactions here: http://www.accessdata.fda.gov/scripts/medwatch/ or
call (800) FDA-1088.
Access a reporting form for complications you've seen that were a result of contact lenses dispensed without a valid
prescription at the Association of Regulatory Boards of Optometry's (ARBO's) Web
site: http://www.arbo.org/arbo.asp?dt=R&doc=Complications. Complete and send the form online or print
it out and fax it to (866) 886-6164.
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