[ASC-media] Media release: permanent contact lenses
jcamedia at starclass.com.au
Thu Aug 19 08:13:09 EST 2004
NATIONAL SCIENCE WEEK 2004 MEDIA RELEASE
August 19, 2004
KEEP AN EYE OUT FOR THE 'PERMANENT' CONTACT LENS
Australian eye researchers are close to achieving what may be the perfect contact lens - one that can be left implanted in the eye indefinitely.
Associate Professor Debbie Sweeney of the Vision Cooperative Research Centre says that clinical trials of the breakthrough technique will start within two years.
"The implantable contact lens, or corneal onlay, has been a research goal for many years," says A/Professor Sweeney. "We've been able to develop our implantable lens because of the wide range of expertise which we could bring together in the Vision CRC.
"We needed specialists in novel polymers, in the physics and chemistry of surfaces, in optical design and even in glues and adhesives," she says. "Then we needed cell biologists to understand the reaction of living to non-living tissue, and to monitor the movement of nutrients and oxygen within the eye itself.
"And of course we will also depend on human volunteers to allow us to fine-tune the technique of implanting the lenses in living human eyes."
A/Professor Sweeney says the technique involves gently removing the outer layer of skin on the cornea, and inserting a flexible polymer implant with a special adhesive backing.
"In fact it is quite a simple surgical operation which can be finished in twenty minutes," she says. "This is far less invasive than corrective laser surgery, and it is also - if necessary - an easily reversible procedure.
"A successful implant may have a life of between ten and twenty years," she says. "The epithelial cells of the eye's skin quickly grow over the surgical site, and the polymer lens itself is biostable - that is, it has no reaction to its living environment - and does not absorb anything from the surrounding material. It is also porous, allowing the necessary passage of the liquids and nutrients of the eye."
A/Professor Sweeney says that this research answers a problem which has challenged eye and vision specialists for many years and will make contact lenses truly competitive with spectacles.
"Even in the nineteenth century, experimenters attempted to implant plexiglass into the cornea, but this was inevitably rejected by the eye of the host," she says. "More recently, there has been some success with 'donated' corneas being sewn into the eye, but with these too there has been a continuing problem of rejection.
"It has been the development of the right polymer, optically clear, porous and biostable, by our research team, which has made the long-term implant possible," she says. Researchers from CSIRO Molecular Sciences, Institute for Eye Research and Vision CRC form this team.
A/Professor Sweeney says that the implantable contact lens will be particularly important to patients with eye problems, who would otherwise be considering laser refractive surgery - an invasive and non-reversible procedure.
A/Professor Sweeney is one of more than 160 eminent Australian scientists available for interview about their work and science in general during National Science Week. For details visit: www.scienceweek.info.au
To contact Professor Debbie Sweeney: phone 02-9385 7408, 0439 600 312
For information on National Science Week:
Telephone: 02 6205 0281
Mobile: 0407 781 891
Facsimile:02 6207 0072
E-mail:scienceweek at orac.net.au
For more events in National Science Week 2004, please visit:
National Science Week is supported by the Commonwealth Government Department of Education Science and Training (DEST) and the Department of Industry Tourism and Resources (DITR).
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